Publications by authors named "Marleen Kok"

35 Publications

A High-Dimensional Window into the Micro-Environment of Triple Negative Breast Cancer.

Cancers (Basel) 2021 Jan 16;13(2). Epub 2021 Jan 16.

Departments of Medical Oncology and Tumor Biology and Immunology, The Netherlands Cancer Institute, 1066 CX Amsterdam, The Netherlands.

Providing effective personalized immunotherapy for triple negative breast cancer (TNBC) patients requires a detailed understanding of the composition of the tumor microenvironment. Both the tumor cell and non-tumor components of TNBC can exhibit tremendous heterogeneity in individual patients and change over time. Delineating cellular phenotypes and spatial topographies associated with distinct immunological states and the impact of chemotherapy will be necessary to optimally time immunotherapy. The clinical successes in immunotherapy have intensified research on the tumor microenvironment, aided by a plethora of high-dimensional technologies to define cellular phenotypes. These high-dimensional technologies include, but are not limited to, single cell RNA sequencing, spatial transcriptomics, T cell repertoire analyses, advanced flow cytometry, imaging mass cytometry, and their integration. In this review, we discuss the cellular phenotypes and spatial patterns of the lymphoid-, myeloid-, and stromal cells in the TNBC microenvironment and the potential value of mapping these features onto tumor cell genotypes.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/cancers13020316DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7830085PMC
January 2021

Adjuvant chemotherapy in small node-negative triple-negative breast cancer.

Eur J Cancer 2020 08 14;135:66-74. Epub 2020 Jun 14.

Department of Medical Oncology, The Netherlands Cancer Institute, PO Box 90203, 1006 BE, Amsterdam, the Netherlands. Electronic address:

Background: Recommendations on adjuvant chemotherapy in pT1N0M0 triple-negative breast cancer (TNBC) differ among international guidelines owing to lack of randomized trial data. We evaluated associations of adjuvant chemotherapy with a long-term outcome in a population-based cohort of pT1N0M0 TNBC.

Methods: All patients diagnosed with pT1N0M0 TNBC in the Netherlands between 2005 and 2016 were identified from the Netherlands Cancer Registry. Patient, tumour and treatment characteristics were recorded. The date and cause of death were obtained from Statistics Netherlands. We used multivariable Cox regression models to evaluate associations of adjuvant chemotherapy with breast cancer-specific survival (BCSS) and overall survival (OS), adjusted for baseline characteristics and performed sensitivity analyses using propensity score (PS) weighting.

Results: We identified 4366 patients: 284 with pT1a, 923 with pT1b and 3159 with pT1c tumours. Adjuvant chemotherapy was administered in 53% of patients. Patients receiving chemotherapy had more unfavourable baseline characteristics including younger age, larger tumours and higher tumour grade. At 8.2 years median follow-up (interquartile range = 5.8-10.9), 671 patients had died, of whom 311 because of breast cancer. After adjustment for baseline characteristics, chemotherapy was associated with improved BCSS (adjusted hazard ratio [aHR] = 0.65; 95% confidence interval [CI] = 0.48-0.89). The effect of chemotherapy differed by tumour size (pT1a: aHR = 4.28, 95% CI = 1.12-16.44; pT1b: aHR = 1.12, 95% CI = 0.51-2.49; pT1c: aHR = 0.60, 95% CI = 0.43-0.82; p = 0.02). Findings for OS were in line with BCSS results. PS-weighting analysis confirmed the results of the primary analysis.

Conclusions: Adjuvant chemotherapy is associated with better BCSS and OS in pT1N0M0 TNBC. Better outcome is most evident in pT1c tumours and may not outweigh harm in pT1a/pT1b tumours.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ejca.2020.04.033DOI Listing
August 2020

Application of a risk-management framework for integration of stromal tumor-infiltrating lymphocytes in clinical trials.

NPJ Breast Cancer 2020 12;6:15. Epub 2020 May 12.

3Division of Molecular Pathology, The Netherlands Cancer Institute, Amsterdam, The Netherlands.

Stromal tumor-infiltrating lymphocytes (sTILs) are a potential predictive biomarker for immunotherapy response in metastatic triple-negative breast cancer (TNBC). To incorporate sTILs into clinical trials and diagnostics, reliable assessment is essential. In this review, we propose a new concept, namely the implementation of a risk-management framework that enables the use of sTILs as a stratification factor in clinical trials. We present the design of a biomarker risk-mitigation workflow that can be applied to any biomarker incorporation in clinical trials. We demonstrate the implementation of this concept using sTILs as an integral biomarker in a single-center phase II immunotherapy trial for metastatic TNBC (TONIC trial, NCT02499367), using this workflow to mitigate risks of suboptimal inclusion of sTILs in this specific trial. In this review, we demonstrate that a web-based scoring platform can mitigate potential risk factors when including sTILs in clinical trials, and we argue that this framework can be applied for any future biomarker-driven clinical trial setting.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41523-020-0155-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7217941PMC
May 2020

Pitfalls in assessing stromal tumor infiltrating lymphocytes (sTILs) in breast cancer.

NPJ Breast Cancer 2020 12;6:17. Epub 2020 May 12.

21Division of Research and Cancer Medicine, Peter MacCallum Cancer Centre, University of Melbourne, Melbourne, VIC Australia.

Stromal tumor-infiltrating lymphocytes (sTILs) are important prognostic and predictive biomarkers in triple-negative (TNBC) and HER2-positive breast cancer. Incorporating sTILs into clinical practice necessitates reproducible assessment. Previously developed standardized scoring guidelines have been widely embraced by the clinical and research communities. We evaluated sources of variability in sTIL assessment by pathologists in three previous sTIL ring studies. We identify common challenges and evaluate impact of discrepancies on outcome estimates in early TNBC using a newly-developed prognostic tool. Discordant sTIL assessment is driven by heterogeneity in lymphocyte distribution. Additional factors include: technical slide-related issues; scoring outside the tumor boundary; tumors with minimal assessable stroma; including lymphocytes associated with other structures; and including other inflammatory cells. Small variations in sTIL assessment modestly alter risk estimation in early TNBC but have the potential to affect treatment selection if cutpoints are employed. Scoring and averaging multiple areas, as well as use of reference images, improve consistency of sTIL evaluation. Moreover, to assist in avoiding the pitfalls identified in this analysis, we developed an educational resource available at www.tilsinbreastcancer.org/pitfalls.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41523-020-0156-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7217863PMC
May 2020

Report on computational assessment of Tumor Infiltrating Lymphocytes from the International Immuno-Oncology Biomarker Working Group.

NPJ Breast Cancer 2020 12;6:16. Epub 2020 May 12.

74Department of Pathology, Northwestern University Feinberg School of Medicine, Chicago, IL USA.

Assessment of tumor-infiltrating lymphocytes (TILs) is increasingly recognized as an integral part of the prognostic workflow in triple-negative (TNBC) and HER2-positive breast cancer, as well as many other solid tumors. This recognition has come about thanks to standardized visual reporting guidelines, which helped to reduce inter-reader variability. Now, there are ripe opportunities to employ computational methods that extract spatio-morphologic predictive features, enabling computer-aided diagnostics. We detail the benefits of computational TILs assessment, the readiness of TILs scoring for computational assessment, and outline considerations for overcoming key barriers to clinical translation in this arena. Specifically, we discuss: 1. ensuring computational workflows closely capture visual guidelines and standards; 2. challenges and thoughts standards for assessment of algorithms including training, preanalytical, analytical, and clinical validation; 3. perspectives on how to realize the potential of machine learning models and to overcome the perceptual and practical limits of visual scoring.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41523-020-0154-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7217824PMC
May 2020

Neoadjuvant immunotherapy leads to pathological responses in MMR-proficient and MMR-deficient early-stage colon cancers.

Nat Med 2020 04 6;26(4):566-576. Epub 2020 Apr 6.

Molecular Oncology and Immunology, Netherlands Cancer Institute, Amsterdam, the Netherlands.

PD-1 plus CTLA-4 blockade is highly effective in advanced-stage, mismatch repair (MMR)-deficient (dMMR) colorectal cancers, yet not in MMR-proficient (pMMR) tumors. We postulated a higher efficacy of neoadjuvant immunotherapy in early-stage colon cancers. In the exploratory NICHE study (ClinicalTrials.gov: NCT03026140), patients with dMMR or pMMR tumors received a single dose of ipilimumab and two doses of nivolumab before surgery, the pMMR group with or without celecoxib. The primary objective was safety and feasibility; 40 patients with 21 dMMR and 20 pMMR tumors were treated, and 3 patients received nivolumab monotherapy in the safety run-in. Treatment was well tolerated and all patients underwent radical resections without delays, meeting the primary endpoint. Of the patients who received ipilimumab + nivolumab (20 dMMR and 15 pMMR tumors), 35 were evaluable for efficacy and translational endpoints. Pathological response was observed in 20/20 (100%; 95% exact confidence interval (CI): 86-100%) dMMR tumors, with 19 major pathological responses (MPRs, ≤10% residual viable tumor) and 12 pathological complete responses. In pMMR tumors, 4/15 (27%; 95% exact CI: 8-55%) showed pathological responses, with 3 MPRs and 1 partial response. CD8PD-1 T cell infiltration was predictive of response in pMMR tumors. These data indicate that neoadjuvant immunotherapy may have the potential to become the standard of care for a defined group of colon cancer patients when validated in larger studies with at least 3 years of disease-free survival data.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41591-020-0805-8DOI Listing
April 2020

The NF-κB Pathway Promotes Tamoxifen Tolerance and Disease Recurrence in Estrogen Receptor-Positive Breast Cancers.

Mol Cancer Res 2020 07 3;18(7):1018-1027. Epub 2020 Apr 3.

Department of Physiology and Biophysics, University of Illinois at Chicago, Chicago, Illinois.

The purpose of this study was to identify critical pathways promoting survival of tamoxifen-tolerant, estrogen receptor α positive (ER) breast cancer cells, which contribute to therapy resistance and disease recurrence. Gene expression profiling and pathway analysis were performed in ER breast tumors of patients before and after neoadjuvant tamoxifen treatment and demonstrated activation of the NF-κB pathway and an enrichment of epithelial-to mesenchymal transition (EMT)/stemness features. Exposure of ER breast cancer cell lines to tamoxifen, and , gives rise to a tamoxifen-tolerant population with similar NF-κB activity and EMT/stemness characteristics. Small-molecule inhibitors and CRISPR/Cas9 knockout were used to assess the role of the NF-κB pathway and demonstrated that survival of tamoxifen-tolerant cells requires NF-κB activity. Moreover, this pathway was essential for tumor recurrence following tamoxifen withdrawal. These findings establish that elevated NF-κB activity is observed in breast cancer cell lines under selective pressure with tamoxifen and , as well as in patient tumors treated with neoadjuvant tamoxifen therapy. This pathway is essential for survival and regrowth of tamoxifen-tolerant cells, and, as such, NF-κB inhibition offers a promising approach to prevent recurrence of ER tumors following tamoxifen exposure. IMPLICATIONS: Understanding initial changes that enable survival of tamoxifen-tolerant cells, as mediated by NF-κB pathway, may translate into therapeutic interventions to prevent resistance and relapse, which remain major causes of breast cancer lethality.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1158/1541-7786.MCR-19-1082DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7335344PMC
July 2020

The path to a better biomarker: application of a risk management framework for the implementation of PD-L1 and TILs as immuno-oncology biomarkers in breast cancer clinical trials and daily practice.

J Pathol 2020 04 9;250(5):667-684. Epub 2020 Apr 9.

Breast Cancer Research Program, Vanderbilt University Medical Center, Nashville, TN, USA.

Immune checkpoint inhibitor therapies targeting PD-1/PD-L1 are now the standard of care in oncology across several hematologic and solid tumor types, including triple negative breast cancer (TNBC). Patients with metastatic or locally advanced TNBC with PD-L1 expression on immune cells occupying ≥1% of tumor area demonstrated survival benefit with the addition of atezolizumab to nab-paclitaxel. However, concerns regarding variability between immunohistochemical PD-L1 assay performance and inter-reader reproducibility have been raised. High tumor-infiltrating lymphocytes (TILs) have also been associated with response to PD-1/PD-L1 inhibitors in patients with breast cancer (BC). TILs can be easily assessed on hematoxylin and eosin-stained slides and have shown reliable inter-reader reproducibility. As an established prognostic factor in early stage TNBC, TILs are soon anticipated to be reported in daily practice in many pathology laboratories worldwide. Because TILs and PD-L1 are parts of an immunological spectrum in BC, we propose the systematic implementation of combined PD-L1 and TIL analyses as a more comprehensive immuno-oncological biomarker for patient selection for PD-1/PD-L1 inhibition-based therapy in patients with BC. Although practical and regulatory considerations differ by jurisdiction, the pathology community has the responsibility to patients to implement assays that lead to optimal patient selection. We propose herewith a risk-management framework that may help mitigate the risks of suboptimal patient selection for immuno-therapeutic approaches in clinical trials and daily practice based on combined TILs/PD-L1 assessment in BC. © 2020 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/path.5406DOI Listing
April 2020

Tumour-infiltrating lymphocytes (TILs) and BRCA-like status in stage III breast cancer patients randomised to adjuvant intensified platinum-based chemotherapy versus conventional chemotherapy.

Eur J Cancer 2020 03 16;127:240-250. Epub 2020 Jan 16.

Department of Medical Oncology, The Netherlands Cancer Institute, Amsterdam, the Netherlands; Division of Molecular Oncology & Immunology, The Netherlands Cancer Institute, Amsterdam, the Netherlands. Electronic address:

Background: The prognostic value of tumour-infiltrating lymphocytes (TILs) differs by breast cancer (BC) subtype. The aim of this study was to evaluate TILs in stage III BC in the context of BRCA1/2-like phenotypes and association with outcome and benefit of intensified platinum-based chemotherapy.

Patients And Methods: Patients participated in a randomised controlled trial of adjuvant intensified platinum-based chemotherapy versus conventional anthracycline-based chemotherapy carried out between 1993 and 1999 in stage III BC. Stromal TILs were scored according to International guidelines in these human epidermal growth factor receptor 2 (HER2)-negative tumours. BRCA-profiles were determined using Comparative Genomic Hybridization.

Results: TIL levels were evaluated in 248 BCs. High TILs were associated with Triple Negative BC (TNBC). BRCA-like tumours harboured higher TILs compared to non-BRCA-like tumours (median TILs of 20% versus 10%, p < 0.01). TIL levels in BRCA1-like tumours were higher compared to BRCA2-like tumours (median TILs of 20% versus 10%, p < 0.001). These correlations remained significant within the oestrogen (ER)-positive subgroup, however not within the TNBC subgroup. In this stage III BC cohort, high TIL level was associated with favourable outcome (TILs per 10% increment, recurrence-free survival (RFS): multivariate hazard ratio (HR) 0.82, 95% confidence interval (CI) 0.71-0.94, p = 0.01; overall survival (OS): multivariate HR 0.80, 95% CI 0.68-0.94, p = 0.01). There was no significant interaction between TILs and benefit of intensified platinum-based chemotherapy.

Conclusion: In this high-risk breast cancer cohort, high TILs were associated with TNBC and BRCA1-like status. Within the ER-positive subgroup, TIL levels were higher in BRCA1-like compared to BRCA2-like tumours. When adjusted for clinical characteristics, TILs were significantly associated with a more favourable outcome in stage III BC patients.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ejca.2019.12.003DOI Listing
March 2020

Comprehensive evaluation of methods to assess overall and cell-specific immune infiltrates in breast cancer.

Breast Cancer Res 2019 12 26;21(1):151. Epub 2019 Dec 26.

Department of Oncology, Laboratory for Translational Breast Cancer Research, KU Leuven, Leuven, Belgium.

Background: Breast cancer (BC) immune infiltrates play a critical role in tumor progression and response to treatment. Besides stromal tumor infiltrating lymphocytes (sTILs) which have recently reached level 1B evidence as a prognostic marker in triple negative BC, a plethora of methods to assess immune infiltration exists, and it is unclear how these compare to each other and if they can be used interchangeably.

Methods: Two experienced pathologists scored sTIL, intra-tumoral TIL (itTIL), and 6 immune cell types (CD3, CD4, CD8, CD20, CD68, FOXP3) in the International Cancer Genomics Consortium breast cancer cohort using hematoxylin and eosin-stained (n = 243) and immunohistochemistry-stained tissue microarrays (n = 254) and whole slides (n = 82). The same traits were evaluated using transcriptomic- and methylomic-based deconvolution methods or signatures.

Results: The concordance correlation coefficient (CCC) between pathologists for sTIL was very good (0.84) and for cell-specific immune infiltrates slightly lower (0.63-0.66). Comparison between tissue microarray and whole slide pathology scores revealed systematically higher values in whole slides (ratio 2.60-5.98). The Spearman correlations between microscopic sTIL and transcriptomic- or methylomic-based assessment of immune infiltrates were highly variable (r = 0.01-0.56). Similar observations were made for cell type-specific quantifications (r = 0.001-0.54). We observed a strong inter-method variability between the omics-derived estimations, which is further cell type dependent. Finally, we demonstrated that most methods more accurately identify highly infiltrated (sTIL ≥ 60%; area under the curve, AUC, 0.64-0.99) as compared to lowly infiltrated tumors (sTIL ≤ 10%; AUC 0.52-0.82).

Conclusions: There is a lower inter-pathologist concordance for cell-specific quantification as compared to overall infiltration quantification. Microscopic assessments are underestimated when considering small cores (tissue microarray) instead of whole slides. Results further highlight considerable differences between the microscopic-, transcriptomic-, and methylomic-based methods in the assessment of overall and cell-specific immune infiltration in BC. We therefore call for extreme caution when assessing immune infiltrates using current methods and emphasize the need for standardized immune characterization beyond TIL.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s13058-019-1239-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6933637PMC
December 2019

Cancer-immune interactions in ER-positive breast cancers: PI3K pathway alterations and tumor-infiltrating lymphocytes.

Breast Cancer Res 2019 08 7;21(1):90. Epub 2019 Aug 7.

Division of Medical Oncology, Netherlands Cancer Institute, Amsterdam, The Netherlands.

Introduction: The presence of tumor-infiltrating lymphocytes (TILs) is correlated with good prognosis and outcome after (immuno)therapy in triple-negative and HER2-positive breast cancer. However, the role of TILs in luminal breast cancer is less clear. Emerging evidence has now demonstrated that genetic aberrations in malignant cells influence the immune landscape of tumors. Phosphatidylinositol 3-kinase (PI3K) is the most common altered pathway in ER-positive breast cancer. It is unknown whether changes in the PI3K pathway result in a different composition of the breast tumor microenvironment. Here we present the retrospective analysis of a prospective randomized trial in ER-positive breast cancer on the prognostic and predictive value of specific tumor-associated lymphocytes in the context of PI3K alterations.

Methods: We included 563 ER-positive tumors from a multicenter trial for stage I to III postmenopausal breast cancer patients, who were randomized to tamoxifen or no adjuvant therapy. The amount of CD8-, CD4-, and FOXP3-positive cells was evaluated by immunohistochemistry and quantified by imaging-analysis software. We analyzed the associations between PIK3CA hotspot mutations, PTEN expression, phosphorylated proteins of the PI3K and MAPK pathway (p-AKT, p-ERK1/2, p-4EBP1, p-p70S6K), and recurrence-free interval after adjuvant tamoxifen or no adjuvant treatment.

Results: CD8-positive lymphocytes were significantly more abundant in PIK3CA-mutated tumors (OR = 1.65; 95% CI 1.03-2.68). While CD4 and FOXP3 were not significantly associated with prognosis, patients with tumors classified as CD8-high had increased risk of recurrence (HR = 1.98; 95% CI 1.14-3.41; multivariable model including PIK3CA status, treatment arm, and other standard clinicopathological variables). Lymphocytes were more often present in tumors with increased PI3K downstream phosphorylation. This was most pronounced for FOXP3-positive cells.

Conclusion: These exploratory analyses of a prospective trial in luminal breast cancer suggest high CD8 infiltration is associated with unfavorable outcome and that PI3K pathway alterations might be associated with the composition of the tumor microenvironment.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s13058-019-1176-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6686400PMC
August 2019

How I treat MSI cancers with advanced disease.

ESMO Open 2019 21;4(Suppl 2):e000511. Epub 2019 May 21.

Medical Oncology, Nederlands Kanker Instituut - Antoni van Leeuwenhoek Ziekenhuis, Amsterdam, The Netherlands. Electronic address:

Mismatch repair deficiency (dMMR) results in microsatellite instability (MSI) and is strongly associated with responsiveness to programmed death-1 receptor (PD-1)-blocking antibodies. Probably the main driver for the observed high efficacy of immune checkpoint inhibitors in dMMR tumours is the remarkably high tumour mutational burden. MSI can be detected using immunohistochemistry and/or PCR. In addition, next-generation sequencing is becoming increasingly available to clinical laboratories as a cost-effective and scalable method to evaluate multiple genetic aberrations including MSI. Efficacy of PD-1-blockade in MSI tumours is similar for patients with colorectal cancer (CRC; objective response rate (ORR) 36%) or a different cancer type (ORR 46% across 14 other cancer types). Based on these results, PD-1-blocking antibody pembrolizumab was the first tumour-agnostic treatment to be granted Food and Drug Administration approval based on the presence of MSI as a biomarker. Currently, there is no approved PD-1-blocking antibody for MSI cancers in Europe. Here, we present our experience with the screening for MSI and the treatment of patients with advanced disease of MSI CRC and non-CRC with immunotherapy.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1136/esmoopen-2019-000511DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6555602PMC
May 2019

Immune induction strategies in metastatic triple-negative breast cancer to enhance the sensitivity to PD-1 blockade: the TONIC trial.

Nat Med 2019 06 13;25(6):920-928. Epub 2019 May 13.

Division of Molecular Oncology & Immunology, The Netherlands Cancer Institute, Amsterdam, the Netherlands.

The efficacy of programmed cell death protein 1 (PD-1) blockade in metastatic triple-negative breast cancer (TNBC) is low, highlighting a need for strategies that render the tumor microenvironment more sensitive to PD-1 blockade. Preclinical research has suggested immunomodulatory properties for chemotherapy and irradiation. In the first stage of this adaptive, non-comparative phase 2 trial, 67 patients with metastatic TNBC were randomized to nivolumab (1) without induction or with 2-week low-dose induction, or with (2) irradiation (3 × 8 Gy), (3) cyclophosphamide, (4) cisplatin or (5) doxorubicin, all followed by nivolumab. In the overall cohort, the objective response rate (ORR; iRECIST) was 20%. The majority of responses were observed in the cisplatin (ORR 23%) and doxorubicin (ORR 35%) cohorts. After doxorubicin and cisplatin induction, we detected an upregulation of immune-related genes involved in PD-1-PD-L1 (programmed death ligand 1) and T cell cytotoxicity pathways. This was further supported by enrichment among upregulated genes related to inflammation, JAK-STAT and TNF-α signaling after doxorubicin. Together, the clinical and translational data of this study indicate that short-term doxorubicin and cisplatin may induce a more favorable tumor microenvironment and increase the likelihood of response to PD-1 blockade in TNBC. These data warrant confirmation in TNBC and exploration of induction treatments prior to PD-1 blockade in other cancer types.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41591-019-0432-4DOI Listing
June 2019

Assessment of PD-L1 expression across breast cancer molecular subtypes, in relation to mutation rate, -like status, tumor-infiltrating immune cells and survival.

Oncoimmunology 2018;7(12):e1509820. Epub 2018 Sep 11.

Division of Molecular Pathology, Netherlands Cancer Institute, Amsterdam, The Netherlands.

To better understand the expression pattern of programmed death-ligand 1 (PD-L1) expression in different breast cancer types, we characterized PD-L1 expression in tumor and tumor-infiltrating immune cells, in relation to mutation rate, -like status and survival. We analyzed 410 primary treatment-naive breast tumors comprising 162 estrogen receptor-positive (ER+) and HER2-, 101 HER2+ and 147 triple-negative (TN) cancers. Pathologists quantified tumor-infiltrating lymphocytes (TILs) and PD-L1 expression in tumor cells and TILs using whole slides and tissue microarray. Mutation rate was assessed by DNA sequencing, -like status using multiplex ligation-dependent probe amplification, and immune landscape by multiplex image analyses of CD4, CD68, CD8, FOXP3, cytokeratin, and PD-L1. Half of PD-L1 scores evaluated by tissue microarray were false negatives compared to whole slide evaluations. We observed at least 1% of PD-L1-positive (PD-L1+) cells in 53.1% of ER+HER2-, 73.3% of HER2+, and 84.4% of TN tumors. PD-L1 expression was higher in ductal compared to lobular carcinomas, also within ER+HER2- tumors (p = 0.04). High PD-L1+ TILs score (> 50%) was independently associated with better outcome in TN tumors (HR = 0.27; 95%CI = 0.10-0.69). Within TN tumors, PD-L1 and TIL scores showed a modest but significant positive association with the number of silent mutations, but no association with -like status. Multiplex image analyses indicated that PD-L1 is expressed on multiple immune cells (CD68+ macrophages, CD4+, FOXP3+, and CD8+ T cells) in the breast tumor microenvironment, independent of the PD-L1 status of the tumor cells. We found no evidence that levels of PD-L1+ TILs in TN breast cancer are driven by high mutation rate or -like status.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1080/2162402X.2018.1509820DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6279322PMC
September 2018

Tumor-infiltrating lymphocytes and ductal carcinoma in situ of the breast: friends or foes?

Mod Pathol 2018 07 20;31(7):1012-1025. Epub 2018 Feb 20.

Department of Pathology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands.

In the past three decades, the detection rate of ductal carcinoma in situ of the breast has dramatically increased due to breast screening programs. As a consequence, about 20% of all breast cancer cases are detected in this early in situ stage. Some ductal carcinoma in situ cases will progress to invasive breast cancer, while other cases are likely to have an indolent biological behavior. The presence of tumor-infiltrating lymphocytes is seen as a promising prognostic and predictive marker in invasive breast cancer, mainly in HER2-positive and triple-negative subtypes. Here, we summarize the current understanding regarding immune infiltrates in invasive breast cancer and highlight recent observations regarding the presence and potential clinical significance of such immune infiltrates in patients with ductal carcinoma in situ. The presence of tumor-infiltrating lymphocytes, their numbers, composition, and potential relationship with genomic status will be discussed. Finally, we propose that a combination of genetic and immune markers may better stratify ductal carcinoma in situ subtypes with respect to tumor evolution.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41379-018-0030-xDOI Listing
July 2018

Independent replication of polymorphisms predicting toxicity in breast cancer patients randomized between dose-dense and docetaxel-containing adjuvant chemotherapy.

Oncotarget 2017 Dec 27;8(69):113531-113542. Epub 2017 Nov 27.

Division of Molecular Pathology, Netherlands Cancer Institute, Amsterdam, The Netherlands.

Introduction: Although pharmacogenomics has evolved substantially, a predictive test for chemotherapy toxicity is still lacking. We compared the toxicity of adjuvant dose-dense doxorubicin-cyclophosphamide (ddAC) and docetaxel-doxorubicin-cyclophosphamide (TAC) in a randomized multicenter phase III trial and replicated previously reported associations between genotypes and toxicity.

Results: 646 patients (97%) were evaluable for toxicity (grade 2 and higher). Whereas AN was more frequent after ddAC ( < 0.001), TAC treated patients more often had PNP ( < 0.001). We could replicate 2 previously reported associations: TECTA (rs1829; OR 4.18, 95% CI 1.84-9.51, 0.001) with PNP, and GSTP1 (rs1138272; OR 2.04, 95% CI 1.13-3.68, 0.018) with PNP.

Materials And Methods: Patients with pT1-3, pN0-3 breast cancer were randomized between six cycles A60C600 every 2 weeks or T75A50C500 every 3 weeks. Associations of 13 previously reported single nucleotide polymorphisms (SNPs) with the most frequent toxicities: anemia (AN), febrile neutropenia (FN) and peripheral neuropathy (PNP) were analyzed using logistic regression models.

Conclusions: In this independent replication, we could replicate an association between 2 out of 13 SNPs and chemotherapy toxicities. These results warrant further validation in order to enable tailored treatment for breast cancer patients.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.18632/oncotarget.22697DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5768344PMC
December 2017

Targeting immune checkpoints in breast cancer: an update of early results.

ESMO Open 2017 14;2(5):e000255. Epub 2017 Nov 14.

Molecular Immunology Unit, Institut Jules Bordet, Université Libre de Bruxelles, Brussels, Belgium.

The immune tumour microenvironment has been shown to play a crucial role in the development and progression of cancer. Expression of gene signatures, reflecting immune activation, and the presence of tumour-infiltrating lymphocytes were associated with favourable outcomes in HER2-positive and triple-negative breast cancer. Recently, immunotherapy with immune checkpoint blockade induced long-lasting responses and improved survival in hard-to-treat malignancies (ie, melanoma and non-small cell lung cancer) and are changing treatment paradigms in a variety of neoplastic diseases. Immune checkpoint blockade has been evaluated in breast cancer, particularly in the triple-negative subtype, with promising results observed in monotherapy or in combination with chemotherapy in the metastatic and neoadjuvant settings. However, identification of patients who are most likely to benefit from immune checkpoint blockade remains challenging, with many patients not responding to treatments and a significant financial cost. The combination of immune checkpoint blockade with conventional cancer treatments such as chemotherapy, radiotherapy, targeted therapies or with other immunotherapies is a promising strategy to potentiate its efficacy in breast cancer although further research is required to effectively identify who will respond to these immunotherapies. In this review we report the most recent results that emerged from trials testing immune checkpoint blockade and potential predictive biomarkers and emphasise the new strategies that are under clinical development in breast cancer.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1136/esmoopen-2017-000255DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5687552PMC
November 2017

Neoadjuvant Therapy for Breast Cancer: Established Concepts and Emerging Strategies.

Drugs 2017 Aug;77(12):1313-1336

Department of Medical Oncology, Netherlands Cancer Institute, Plesmanlaan 121, 1066CX, Amsterdam, The Netherlands.

In the last decade, the systemic treatment approach for patients with early breast cancer has partly shifted from adjuvant treatment to neoadjuvant treatment. Systemic treatment administration started as a 'one size fits all' approach but is currently customized according to each breast cancer subtype. Systemic treatment in a neoadjuvant setting is at least as effective as in an adjuvant setting and has several additional advantages. First, it enables response monitoring and provides prognostic information; second, it downstages the tumor, allowing for less extensive surgery, improved cosmetic outcomes, and reduced postoperative complications such as lymphedema; and third, it enables early development of new treatment strategies by using pathological complete remission as a surrogate outcome of event-free and overall survival. In this review we give an overview of the current standard of neoadjuvant systemic treatment strategies for the three main subtypes of breast cancer: hormone receptor-positive, triple-negative, and human epidermal growth factor receptor 2-positive. Additionally, we summarize drugs that are under investigation for use in the neoadjuvant setting.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s40265-017-0774-5DOI Listing
August 2017

A STING Agonist Given with OX40 Receptor and PD-L1 Modulators Primes Immunity and Reduces Tumor Growth in Tolerized Mice.

Cancer Immunol Res 2017 06 8;5(6):468-479. Epub 2017 May 8.

Department of Oncology, Kimmel Cancer Center, Johns Hopkins School of Medicine, Baltimore, Maryland.

Stimulator of interferon genes (STING) signaling induces IFNβ production by intratumoral dendritic cells (DC), driving T-cell priming and recruitment into the tumor microenvironment (TME). We examined to what extent preexisting antigen-specific tolerance influenced the efficacy of delivery of a potent STING-activating cyclic dinucleotide (CDN), ADU S-100, against established HER-2 breast tumors. ADU S-100 induced HER-2-specific CD8 T-cell priming and durable tumor clearance in 100% of nontolerant parental FVB/N mice. In contrast, ADU S-100 did not sufficiently prime HER-2-specific CD8 T cells in tolerant neu/N mice, resulting in only delayed tumor growth and tumor clearance in 10% of the mice. No differences in IFNβ production, DC priming, or HER-2-specific CD8 T-cell trafficking were detected between FVB/N and neu/N mice. However, activation and expansion of HER-2-specific CD8 T cells were defective in neu/N mice. Immune cell infiltrates of untreated tumor-bearing neu/N mice expressed high numbers of PD1 and OX40 receptors on their CD8 T cells, and PD-L1 was highly expressed on both myeloid and tumor cells. Modulating PD-L1 and OX40 receptor signaling combined with intratumoral ADU S-100 administration enhanced HER-2-specific CD8 T-cell activity, clearing tumors in 40% of neu/N mice. Thus, intratumoral STING agonists could potently prime tumor antigen-specific CD8 T-cell responses, and adding PD-L1 blockade and OX40 receptor activation can overcome antigen-enforced immune tolerance to induce tumor regression. .
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1158/2326-6066.CIR-16-0284DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5550830PMC
June 2017

Targeting the programmed cell death-1 pathway in breast and ovarian cancer.

Curr Opin Obstet Gynecol 2016 Apr;28(2):142-7

aDepartment of Oncology, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA bThe Netherlands Cancer Institute, Amsterdam, the Netherlands cThe Kelly Gynecologic Oncology Service, Department of Obstetrics and Gynecology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.

Purpose Of Review: Immune checkpoint blockade is changing cancer therapy. Targeting the programmed cell death-1 (PD-1) pathway releases T cells from inhibitory signals within the tumor microenvironment, thereby activating a latent antitumor immune response. Here, we review the biology underlying the activity of PD-1/programmed cell death-ligand 1 (PD-L1) antagonists, and data describing their clinical activity in breast and ovarian cancer.

Recent Findings: Several antagonists of PD-1 and PD-L1 have been tested in breast and ovarian cancer. These drugs are generally well tolerated, with some immune-related adverse events that are typically easily managed. Objective response rates generally range from about 10 to 20% in both breast cancer and ovarian cancer, with durable responses noted in multiple trials. Selecting patients with PD-L1 expression by cells within the tumor microenvironment appears to enrich for responses. These agents are under accelerated development based on these promising early data.

Summary: Monoclonal antibody-based blockade of the PD-1 pathway results in objective and durable clinical responses in a subset of patients with breast or ovarian cancers, particularly those with PD-L1-positive cells within the tumor microenvironment. Current priorities are to refine biomarkers of therapeutic response, and to develop combination immunotherapy strategies that integrate PD-1/PD-L1 antagonists with both standard and immune-based cancer therapies to increase efficacy.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/GCO.0000000000000257DOI Listing
April 2016

Protein Kinase A-induced tamoxifen resistance is mediated by anchoring protein AKAP13.

BMC Cancer 2015 Aug 14;15:588. Epub 2015 Aug 14.

Division of Molecular Pathology, the Netherlands Cancer Institute, Amsterdam, The Netherlands.

Background: Estrogen Receptor alpha (ERα)-positive breast cancer patients receive endocrine therapy, often in the form of tamoxifen. However, resistance to tamoxifen is frequently observed. A signalling cascade that leads to tamoxifen resistance is dictated by activation of the Protein Kinase A (PKA) pathway, which leads to phosphorylation of ERα on Serine 305 and receptor activation, following tamoxifen binding. Thus far, it remains elusive what protein complexes enable the PKA-ERα interaction resulting in ERα Serine 305 phosphorylation.

Methods: We performed immunohistochemistry to detect ERαSerine 305 phosphorylation in a cohort of breast cancer patients who received tamoxifen treatment in the metastatic setting. From the same tumor specimens, Agilent 44 K gene expression analyses were performed and integrated with clinicopathological data and survival information. In vitro analyses were performed using MCF7 breast cancer cells, which included immunoprecipitations and Fluorescence Resonance Energy Transfer (FRET) analyses to illustrate ERα complex formation. siRNA mediated knockdown experiments were performed to assess effects on ERαSerine 305 phosphorylation status, ERα/PKA interactions and downstream responsive gene activity.

Results: Stratifying breast tumors on ERα Serine 305 phosphorylation status resulted in the identification of a gene network centered upon AKAP13. AKAP13 mRNA expression levels correlate with poor outcome in patients who received tamoxifen treatment in the metastatic setting. In addition, AKAP13 mRNA levels correlate with ERαSerine 305 phosphorylation in breast tumor samples, suggesting a functional connection between these two events. In a luminal breast cancer cell line, AKAP13 was found to interact with ERα as well as with a regulatory subunit of PKA. Knocking down of AKAP13 prevented PKA-mediated Serine 305 phosphorylation of ERα and abrogated PKA-driven tamoxifen resistance, illustrating that AKAP13 is an essential protein in this process.

Conclusions: We show that the PKA-anchoring protein AKAP13 is essential for the phosphorylation of ERαS305, which leads to tamoxifen resistance both in cell lines and tamoxifen-treated breast cancer patients.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s12885-015-1591-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4536754PMC
August 2015

Decreased expression of ABAT and STC2 hallmarks ER-positive inflammatory breast cancer and endocrine therapy resistance in advanced disease.

Mol Oncol 2015 Jun 4;9(6):1218-33. Epub 2015 Mar 4.

Translational Cancer Research Unit, GZA Hospitals St-Augustinus, Oosterveldlaan 24, Antwerp B2610, Belgium; Department of Oncology, KU Leuven, Leuven, Belgium.

Background: Patients with Estrogen Receptor α-positive (ER+) Inflammatory Breast Cancer (IBC) are less responsive to endocrine therapy compared with ER+ non-IBC (nIBC) patients. The study of ER+ IBC samples might reveal biomarkers for endocrine resistant breast cancer.

Materials & Methods: Gene expression profiles of ER+ samples from 201 patients were explored for genes that discriminated between IBC and nIBC. Classifier genes were applied onto clinically annotated expression data from 947 patients with ER+ breast cancer and validated with RT-qPCR for 231 patients treated with first-line tamoxifen. Relationships with metastasis-free survival (MFS) and progression-free survival (PFS) following adjuvant and first-line endocrine treatment, respectively, were investigated using Cox regression analysis.

Results: A metagene of six genes including the genes encoding for 4-aminobutyrate aminotransferase (ABAT) and Stanniocalcin-2 (STC2) were identified to distinguish 22 ER+ IBC from 43 ER+ nIBC patients and remained discriminatory in an independent series of 136 patients. The metagene and two genes were not prognostic in 517 (neo)adjuvant untreated lymph node-negative ER+ nIBC breast cancer patients. Only ABAT was related to outcome in 250 patients treated with adjuvant tamoxifen. Three independent series of in total 411 patients with advanced disease showed increased metagene scores and decreased expression of ABAT and STC2 to be correlated with poor first-line endocrine therapy outcome. The biomarkers remained predictive for first-line tamoxifen treatment outcome in multivariate analysis including traditional factors or published signatures. In an exploratory analysis, ABAT and STC2 protein expression levels had no relation with PFS after first-line tamoxifen.

Conclusions: This study utilized ER+ IBC to identify a metagene including ABAT and STC2 as predictive biomarkers for endocrine therapy resistance.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.molonc.2015.02.006DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5528763PMC
June 2015

Immunological profile of Fanconi anemia: a multicentric retrospective analysis of 61 patients.

Am J Hematol 2013 Jun 2;88(6):472-6. Epub 2013 May 2.

Department of Pediatrics/Willem-Alexander Children's Hospital, Division of Immunology, Haematology and Stem Cell Transplantation, Leiden University Medical Center, Leiden, The Netherlands.

In this study, the immunological status of 61 patients with Fanconi anemia (FA) with advanced marrow failure before hematopoietic stem cell transplantation was analyzed by assessing the phenotype of peripheral blood lymphocytes, serum immunoglobulin (Ig) levels, and inflammatory cytokines. In patients with FA, total absolute lymphocytes (P < 0.0001), B cells (P < 0.0001), and NK cells (P = 0.003) were reduced when compared with normal controls. T cells (CD3), that is, cytotoxic T cells, naïve T cells, and regulatory T cells, showed a relative increase when compared with controls. Serum levels of IgG (P < 0.0001) and IgM (P = 0.004) were significantly lower, whereas IgA level was higher (P < 0.0001) than in normal controls. TGF-β (P = 0.007) and interleukin (IL)-6 (P = 0.0007) levels were increased in the serum of patients when compared with controls, whereas sCD40L level decreases (P < 0.0001). No differences were noted in the serum levels of IL-1β, IL-2, IL-4, IL-10, IL-13, IL-17, and IL-23 between FA subjects and controls. This comprehensive immunological study shows that patients with FA with advanced marrow failure have an altered immune status. This is in accordance with some characteristics of FA such as the proinflammatory and proapoptotic status. In addition, B lymphocyte failure may make tight and early immunological monitoring advisable.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/ajh.23435DOI Listing
June 2013

Oestrogen receptor-co-factor-chromatin specificity in the transcriptional regulation of breast cancer.

EMBO J 2011 Oct 14;30(23):4764-76. Epub 2011 Oct 14.

The Netherlands Cancer Institute, Amsterdam, The Netherlands.

The complexity of oestrogen receptor α (ERα)-mediated transcription is becoming apparent, but global insight into the co-regulatory proteins that assist ERα transcription is incomplete. Here, we present the most comprehensive chromatin-binding landscape of ERα co-regulatory proteins to date. We map by ChIP-seq the essential p160 co-regulators (SRC1, SRC2 and SRC3), and the histone acetyl transferases p300 and CBP in MCF-7 breast cancer cells. We find a complex network of co-regulator binding, with preferential binding sites for each co-regulator. Unlike previous suggestions, we find SRC recruitment almost exclusively following ligand treatment. Interestingly, we find specific subsets of genes regulated by ligand-dependent and -independent co-regulator recruitment. Co-factor-binding profiles were integrated with expression data from cell lines and primary tumour cohorts, to reveal specific transcriptional networks that influence clinical outcome. Genes that are bound by SRC3, but not other p160 proteins, have predictive value in cohorts of breast cancer patients. By generating a robust and global view of co-factor-binding properties, we discover new levels of co-regulator complexity, but also reveal specific gene networks that may influence endocrine response.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/emboj.2011.368DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3243612PMC
October 2011

The CYP2C19*2 genotype predicts tamoxifen treatment outcome in advanced breast cancer patients.

Pharmacogenomics 2011 Aug 10;12(8):1137-46. Epub 2011 Aug 10.

Erasmus MC Rotterdam, The Netherlands.

Aims: Tamoxifen is metabolized by cytochrome P450s, with an important role for CYP2D6. Recently, we demonstrated in 80 patients that CYP2C19*2 is associated with increased survival in breast cancer patients using tamoxifen. Here, we aimed to confirm this in a large group of 499 patients.

Materials & Methods: A total of 499 estrogen receptor-positive primary breast tumor specimens of advanced disease patients treated with first-line tamoxifen were genotyped for CYP2C19*2 and *17 variant alleles, with primary end point time-to-treatment failure (TTF). Effects of CYP2C19, independent of treatment, were analyzed in 243 primary systematic untreated patients.

Results: CYP2C19*2 hetero- and homozygote patients combined showed significantly longer TTFs (hazard ratio [HR]: 0.72; 95% CI: 0.57-0.90; p = 0.004). In multivariate analysis, including CYP2D6*4 status, CYP2C19*2 remained independently associated with TTF (HR: 0.73; 95% CI: 0.58-0.91; p = 0.007). In untreated patients, the CYP2C19*17 allele was significantly associated with a longer disease-free interval (HR: 0.66; 95%CI: 0.46-0.95; p = 0.025).

Conclusion: CYP2C19 genotyping is potentially important for tamoxifen therapy for advanced disease and for breast cancer prognosis.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.2217/pgs.11.54DOI Listing
August 2011

PKA-induced phosphorylation of ERα at serine 305 and high PAK1 levels is associated with sensitivity to tamoxifen in ER-positive breast cancer.

Breast Cancer Res Treat 2011 Jan 9;125(1):1-12. Epub 2010 Mar 9.

Department of Experimental Therapy, Netherlands Cancer Institute, Amsterdam, The Netherlands.

Phosphorylation of estrogen receptor α at serine 305 (ERαS305-P) by protein kinase A (PKA) or p21-activated kinase 1 (PAK1) has experimentally been associated with tamoxifen sensitivity. Here, we investigated the clinical application of this knowledge to predict tamoxifen resistance in ER-positive breast cancer patients. Using immunohistochemistry, a score including PAK1 and co-expression of PKA and ERαS305-P (PKA/ERαS305-P) was developed on a training set consisting of 103 patients treated with tamoxifen for metastatic disease, and validated on 231 patients randomized between adjuvant tamoxifen or no treatment. In the training set, PAK1 levels were associated with tumor progression after tamoxifen (HR 1.57, 95% CI 0.99-2.48), as was co-expression of PKA and ERαS305-P (HR 2.00, 95% CI 1.14-3.52). In the validation set, a significant tamoxifen benefit was found among the 73% patients negative for PAK1 and PKA/ERαS305-P (HR 0.54, 95% CI 0.34-0.87), while others (27%) were likely to have no benefit from tamoxifen (HR 0.88, 95% 0.42-1.82). The test for interaction showed a significant difference in recurrence-free survival between groups defined by PAK1 and PKA/ERαS305-P (P = 0.037). Elevated PAK1 and PKA/ERαS305-P appeared to influence tamoxifen sensitivity. Both PAK1 and PKA/ERαS305-P levels were associated with sensitivity to tamoxifen in breast tumors and the combination of these variables should be considered in predicting tamoxifen benefit.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s10549-010-0798-yDOI Listing
January 2011

Estrogen receptor-alpha phosphorylation at serine-118 and tamoxifen response in breast cancer.

J Natl Cancer Inst 2009 Dec;101(24):1725-9

Department of Experimental Therapy, Netherlands Cancer Institute, Amsterdam, The Netherlands.

Although estrogen receptor-alpha (ER) [corrected] is a marker used to identify breast cancer patients most likely to benefit from endocrine therapy, approximately 50% of ER-positive [corrected] breast carcinomas are resistant to tamoxifen. Preclinical studies have shown that phosphorylation of ER [corrected] at serine-118 (ER alpha S118-P) is required for tamoxifen-mediated inhibition of ER-induced [corrected] gene expression. We evaluated the association between recurrence-free survival after tamoxifen treatment and ER alpha S118-P expression by use of Cox proportional hazards regression. Data were from 239 premenopausal patients with breast cancer who participated in a randomized trial of 2 years of adjuvant tamoxifen treatment vs no systemic treatment. ER alpha S118-P expression was assessed by immunohistochemistry and categorized by use of the Allred score (low expression = score of 0-6; high expression = score of 7-8). All statistical tests were two-sided. Compared with systemically untreated patients, we found evidence of a benefit from adjuvant tamoxifen among patients whose tumors had high ER alpha S118-P expression (23.7 recurrences per 1000 person-years versus 72.2 recurrences per 1000 person-years, hazard ratio [HR] of recurrence = 0.36, 95% confidence interval [CI] = 0.20 to 0.65) but not among patients whose tumors had low expression (51.0 recurrences per 1000 person-years versus 57.0 recurrences per 1000 person-years, HR of recurrence = 0.87, 95% CI = 0.51 to 1.48), a statistically significant difference (P for interaction = .037). ER alpha 118-P was not associated with recurrence-free survival among untreated patients. Thus, ER alpha S118-P expression appears to be associated with response to tamoxifen. [corrected]
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1093/jnci/djp412DOI Listing
December 2009

Microarray-based determination of estrogen receptor, progesterone receptor, and HER2 receptor status in breast cancer.

Clin Cancer Res 2009 Nov 3;15(22):7003-11. Epub 2009 Nov 3.

Agendia BV, Academic Medical Centre, Amsterdam, The Netherlands.

Purpose: The level of estrogen receptor (ER), progesterone receptor (PR), and HER2 aids in the determination of prognosis and treatment of breast cancer. Immunohistochemistry is currently the predominant method for assessment, but differences in methods and interpretation can substantially affect the accuracy, resulting in misclassification. Here, we investigated the association of microarray-based mRNA expression levels compared with immunohistochemistry.

Experimental Design: Microarray mRNA quantification of ER, PR, and HER2 was done by the developed TargetPrint test and compared with immunohistochemical assessment for breast tumors from 636 patients. Immunohistochemistry was done in a central laboratory and in an independent reference laboratory according to American Society of Clinical Oncology/College of American Pathologists guidelines for 100 cases. For HER2 immunohistochemistry 2+ cases, additional chromogenic in situ hybridization (CISH) was used to determine the final status.

Results: ER concordance between microarray and central immunohistochemistry was 93% [95% confidence interval (95% CI), 91-95%]. Only 4% of immunohistochemistry-positive samples were classified negative using microarray, whereas 18% of immunohistochemistry-negative samples showed a positive microarray ER status. Concordance for PR was 83% (95% CI, 80-86%) and 96% of all samples showed an identical classification of HER2 status by microarray and immunohistochemistry/CISH (95% CI, 94-98%). Nine percent of immunohistochemistry HER2-positive samples showed a negative microarray classification. Detailed review of 11 cases with discordant classifications by American Society of Clinical Oncology/College of American Pathologists and central immunohistochemistry indicated that microarray assessment was likely to add additional information in 5 cases.

Conclusion: Microarray-based readout of ER, PR, and HER2 shows a high concordance with immunohistochemistry/CISH and provides an additional, objective, and quantitative assessment of tumor receptor status in breast cancer.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1158/1078-0432.CCR-09-0449DOI Listing
November 2009

Mammosphere-derived gene set predicts outcome in patients with ER-positive breast cancer.

J Pathol 2009 Jul;218(3):316-26

Departments of Pathology, Netherlands Cancer Institute/Antoni van Leeuwenhoek Hospital, Amsterdam, The Netherlands.

Tumourigenic subpopulations with stem cell-like features have been identified in breast tumours and breast cancer cell lines. The hormone receptor status, molecular characteristics and clinical significance of these cells are still matters of debate. Enrichment for tumourigenic cells without the requirement of surface markers can be achieved by the in vitro mammosphere culture assay. Here we compared the hormone receptor status and genome-wide gene expression profiles of mammospheres derived from four oestrogen-receptor (ER) positive breast cancer cell lines with those of the respective parental cells. Immunohistochemistry and gene expression profiling revealed a significant reduction in the expression of progesterone receptor, proliferation and cell cycle regulated genes in mammospheres when compared to parental cell lines. The 200 most differentially expressed genes between mammospheres and parental cell lines were used to generate a 'mammosphere-derived' gene set. Hierarchical clustering of gene expression profiles of two independent cohorts of primary ER-positive cancers based on the 'mammosphere-derived' gene set revealed that the subgroup of breast cancers with profiles similar to those of mammospheres has a significantly longer overall survival. In conclusion, tumour-initiating breast cancer cells grown in mammospheres seem to reside in a quiescent state. ER-positive breast cancers with expression profiles similar to those of mammospheres have a better outcome, providing evidence in support of the concept that outcome of patients with ER-positive disease is for a large part determined by cell cycle and proliferation activity.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/path.2544DOI Listing
July 2009