Publications by authors named "Stephane Ferretti"

27 Publications

  • Page 1 of 1

Pharmacokinetic-pharmacodynamic guided optimisation of dose and schedule of CGM097, an HDM2 inhibitor, in preclinical and clinical studies.

Br J Cancer 2021 Aug 17;125(5):687-698. Epub 2021 Jun 17.

Department of Medical Oncology, Centre Léon Bérard, Lyon, France.

Background: CGM097 inhibits the p53-HDM2 interaction leading to downstream p53 activation. Preclinical in vivo studies support clinical exploration while providing preliminary evidence for dosing regimens. This first-in-human phase I study aimed at assessing the safety, MTD, PK/PD and preliminary antitumor activity of CGM097 in advanced solid tumour patients (NCT01760525).

Methods: Fifty-one patients received oral treatment with CGM097 10-400 mg 3qw (n = 31) or 300-700 mg 3qw 2 weeks on/1 week off (n = 20). Choice of dose regimen was guided by PD biomarkers, and quantitative models describing the effect of CGM097 on circulating platelet and PD kinetics.

Results: No dose-limiting toxicities were reported in any regimens. The most common treatment-related grade 3/4 AEs were haematologic events. PK/PD models well described the time course of platelet and serum GDF-15 changes, providing a tool to predict response to CGM097 for dose-limiting thrombocytopenia and GDF-15 biomarker. The disease control rate was 39%, including one partial response and 19 patients in stable disease. Twenty patients had a cumulative treatment duration of >16 weeks, with eight patients on treatment for >32 weeks. The MTD was not determined.

Conclusions: Despite delayed-onset thrombocytopenia frequently observed, the tolerability of CGM097 appears manageable. This study provided insights on dosing optimisation for next-generation HDM2 inhibitors.

Translational Relevance: Haematologic toxicity with delayed thrombocytopenia is a well-known on-target effect of HDM2 inhibitors. Here we have developed a PK/PD guided approach to optimise the dose and schedule of CGM097, a novel HDM2 inhibitor, using exposure, platelets and GDF-15, a known p53 downstream target to predict patients at higher risk to develop thrombocytopenia. While CGM097 had shown limited activity, with disease control rate of 39% and only one patient in partial response, the preliminary data from the first-in-human escalation study together with the PK/PD modeling provide important insights on how to optimize dosing of next generation HDM2 inhibitors to mitigate hematologic toxicity.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41416-021-01444-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8405607PMC
August 2021

PAX8 and MECOM are interaction partners driving ovarian cancer.

Nat Commun 2021 04 26;12(1):2442. Epub 2021 Apr 26.

Chemical Biology and Therapeutics, Novartis Institutes for Biomedical Research, Basel, Switzerland.

The transcription factor PAX8 is critical for the development of the thyroid and urogenital system. Comprehensive genomic screens furthermore indicate an additional oncogenic role for PAX8 in renal and ovarian cancers. While a plethora of PAX8-regulated genes in different contexts have been proposed, we still lack a mechanistic understanding of how PAX8 engages molecular complexes to drive disease-relevant oncogenic transcriptional programs. Here we show that protein isoforms originating from the MECOM locus form a complex with PAX8. These include MDS1-EVI1 (also called PRDM3) for which we map its interaction with PAX8 in vitro and in vivo. We show that PAX8 binds a large number of genomic sites and forms transcriptional hubs. At a subset of these, PAX8 together with PRDM3 regulates a specific gene expression module involved in adhesion and extracellular matrix. This gene module correlates with PAX8 and MECOM expression in large scale profiling of cell lines, patient-derived xenografts (PDXs) and clinical cases and stratifies gynecological cancer cases with worse prognosis. PRDM3 is amplified in ovarian cancers and we show that the MECOM locus and PAX8 sustain in vivo tumor growth, further supporting that the identified function of the MECOM locus underlies PAX8-driven oncogenic functions in ovarian cancer.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41467-021-22708-wDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8076227PMC
April 2021

CARD10 cleavage by MALT1 restricts lung carcinoma growth in vivo.

Oncogenesis 2021 Apr 6;10(4):32. Epub 2021 Apr 6.

Autoimmunity, Transplantation & Inflammation, Novartis Institutes for BioMedical Research (NIBR), Novartis Campus, Basel, Switzerland.

CARD-CC complexes involving BCL10 and MALT1 are major cellular signaling hubs. They govern NF-κB activation through their scaffolding properties as well as MALT1 paracaspase function, which cleaves substrates involved in NF-κB regulation. In human lymphocytes, gain-of-function defects in this pathway lead to lymphoproliferative disorders. CARD10, the prototypical CARD-CC protein in non-hematopoietic cells, is overexpressed in several cancers and has been associated with poor prognosis. However, regulation of CARD10 remains poorly understood. Here, we identified CARD10 as the first MALT1 substrate in non-hematopoietic cells and showed that CARD10 cleavage by MALT1 at R587 dampens its capacity to activate NF-κB. Preventing CARD10 cleavage in the lung tumor A549 cell line increased basal levels of IL-6 and extracellular matrix components in vitro, and led to increased tumor growth in a mouse xenograft model, suggesting that CARD10 cleavage by MALT1 might be a built-in mechanism controlling tumorigenicity.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41389-021-00321-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8024357PMC
April 2021

Therapeutic Assessment of Targeting ASNS Combined with l-Asparaginase Treatment in Solid Tumors and Investigation of Resistance Mechanisms.

ACS Pharmacol Transl Sci 2021 Feb 13;4(1):327-337. Epub 2021 Jan 13.

Disease area Oncology, Novartis Institute for Biomedical Research, Basel, Switzerland.

Asparagine deprivation by l-asparaginase (L-ASNase) is an effective therapeutic strategy in acute lymphoblastic leukemia, with resistance occurring due to upregulation of ASNS, the only human enzyme synthetizing asparagine ( , (1), 629-654). l-Asparaginase efficacy in solid tumors is limited by dose-related toxicities ( 2017, pp 1413-1422). Large-scale loss of function genetic screens identified ASNS as a cancer dependency in several solid malignancies ( , (3), 564-576.e16. , (3), 577-592.e10). Here we evaluate the therapeutic potential of targeting ASNS in melanoma cells. While we confirm dependency on ASNS silencing, this is largely dispensable for tumor growth, even in the face of asparagine deprivation, prompting us to characterize such a resistance mechanism to devise novel therapeutic strategies. Using quantitative proteome and transcriptome profiling, we characterize the compensatory mechanism elicited by ASNS knockout melanoma cells allowing their survival. Mechanistically, a genome-wide CRISPR screen revealed that such a resistance mechanism is elicited by a dual axis: GCN2-ATF4 aimed at restoring amino acid levels and MAPK-BCLXL to promote survival. Importantly, pharmacological inhibition of such nodes synergizes with l-asparaginase-mediated asparagine deprivation in ASNS deficient cells suggesting novel potential therapeutic combinations in melanoma.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acsptsci.0c00196DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7887857PMC
February 2021

p53 dynamics vary between tissues and are linked with radiation sensitivity.

Nat Commun 2021 02 9;12(1):898. Epub 2021 Feb 9.

Department of Systems Biology and the Ludwig Center at Harvard, Blavatnik Institute at Harvard Medical School, Boston, MA, USA.

Radiation sensitivity varies greatly between tissues. The transcription factor p53 mediates the response to radiation; however, the abundance of p53 protein does not correlate well with the extent of radiosensitivity across tissues. Given recent studies showing that the temporal dynamics of p53 influence the fate of cultured cells in response to irradiation, we set out to determine the dynamic behavior of p53 and its impact on radiation sensitivity in vivo. We find that radiosensitive tissues show prolonged p53 signaling after radiation, while more resistant tissues show transient p53 activation. Sustaining p53 using a small molecule (NMI801) that inhibits Mdm2, a negative regulator of p53, reduced viability in cell culture and suppressed tumor growth. Our work proposes a mechanism for the control of radiation sensitivity and suggests tools to alter the dynamics of p53 to enhance tumor clearance. Similar approaches can be used to enhance killing of cancer cells or reduce toxicity in normal tissues following genotoxic therapies.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41467-021-21145-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7873198PMC
February 2021

Translational Modeling of Anticancer Efficacy to Predict Clinical Outcomes in a First-in-Human Phase 1 Study of MDM2 Inhibitor HDM201.

AAPS J 2021 02 7;23(2):28. Epub 2021 Feb 7.

Novartis Institutes for BioMedical Research (NIBR), Basel, Switzerland.

We report on a retrospective model-based assessment of the predictive value of translating antitumor drug activity from in vivo experiments to a phase I clinical study in cancer patients treated with the MDM2 inhibitor, HDM201. Tumor growth inhibition models were developed describing the longitudinal tumor size data in human-derived osteosarcoma xenograft rats and in 96 solid tumor patients under different HDM201 treatment schedules. The model structure describing both datasets captures the delayed drug effect on tumor growth via a series of signal transduction compartments, including a resistance component. The models assumed a drug-killing effect on both sensitive and resistant cells and parameterized to estimate two tumor static plasma drug concentrations for sensitive (TSC) and resistant cells (TSC). No change of TSC and TSC with schedule was observed, implying that antitumor activity for HDM201 is independent of treatment schedule. Preclinical and clinical model-derived TSC were comparable (48 ng/mL vs. 74 ng/mL) and demonstrating TSC as a translatable metric for antitumor activity in clinic. Schedule independency was further substantiated from modeling of clinical serum growth differentiation factor-15 (GDF-15) as a downstream marker of p53 pathway activation. Equivalent cumulative induction of GDF-15 was achieved across schedules when normalized to an equivalent total dose. These findings allow for evaluation of optimal dosing schedules by maximizing the total dose per treatment cycle while mitigating safety risk with periods of drug holiday. This approach helped guide a phase I dose escalation study in the selection of an optimal dose and schedule for HDM201.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1208/s12248-020-00551-zDOI Listing
February 2021

Genetic heterogeneity and clonal evolution during metastasis in breast cancer patient-derived tumor xenograft models.

Comput Struct Biotechnol J 2020 31;18:323-331. Epub 2020 Jan 31.

Disease Area Oncology, Novartis Institutes for BioMedical Research, Basel, Switzerland.

Genetic heterogeneity within a tumor arises by clonal evolution, and patients with highly heterogeneous tumors are more likely to be resistant to therapy and have reduced survival. Clonal evolution also occurs when a subset of cells leave the primary tumor to form metastases, which leads to reduced genetic heterogeneity at the metastatic site. Although this process has been observed in human cancer, experimental models which recapitulate this process are lacking. Patient-derived tumor xenografts (PDX) have been shown to recapitulate the patient's original tumor's intra-tumor genetic heterogeneity, as well as its genomics and response to treatment, but whether they can be used to model clonal evolution in the metastatic process is currently unknown. Here, we address this question by following genetic changes in two breast cancer PDX models during metastasis. First, we discovered that mouse stroma can be a confounding factor in assessing intra-tumor heterogeneity by whole exome sequencing, thus we developed a new bioinformatic approach to correct for this. Finally, in a spontaneous, but not experimental (tail-vein) metastasis model we observed a loss of heterogeneity in PDX metastases compared to their orthotopic "primary" tumors, confirming that PDX models can faithfully mimic the clonal evolution process undergone in human patients during metastatic spreading.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.csbj.2020.01.008DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7026725PMC
January 2020

Dual inhibition of MDM2 and MDM4 in virus-positive Merkel cell carcinoma enhances the p53 response.

Proc Natl Acad Sci U S A 2019 01 31;116(3):1027-1032. Epub 2018 Dec 31.

Program in Virology, Graduate School of Arts and Sciences, Harvard University, Cambridge, MA 02138;

Merkel cell polyomavirus (MCV) contributes to approximately 80% of all Merkel cell carcinomas (MCCs), a highly aggressive neuroendocrine carcinoma of the skin. MCV-positive MCC expresses small T antigen (ST) and a truncated form of large T antigen (LT) and usually contains wild-type p53 (TP53) and RB (RB1). In contrast, virus-negative MCC contains inactivating mutations in TP53 and RB1. While the MCV-truncated LT can bind and inhibit RB, it does not bind p53. We report here that MCV LT binds to RB, leading to increased levels of ARF, an inhibitor of MDM2, and activation of p53. However, coexpression of ST reduced p53 activation. MCV ST recruits the MYC homologue MYCL (L-Myc) to the EP400 chromatin remodeler complex and transactivates specific target genes. We observed that depletion of EP400 in MCV-positive MCC cell lines led to increased p53 target gene expression. We suspected that the MCV ST-MYCL-EP400 complex could functionally inactivate p53, but the underlying mechanism was not known. Integrated ChIP and RNA-sequencing analysis following EP400 depletion identified MDM2 as well as CK1α, an activator of MDM4, as target genes of the ST-MYCL-EP400 complex. In addition, MCV-positive MCC cells expressed high levels of MDM4. Combining MDM2 inhibitors with lenalidomide targeting CK1α or an MDM4 inhibitor caused synergistic activation of p53, leading to an apoptotic response in MCV-positive MCC cells and MCC-derived xenografts in mice. These results support dual targeting of MDM2 and MDM4 in virus-positive MCC and other p53 wild-type tumors.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1073/pnas.1818798116DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6338866PMC
January 2019

In vitro and in vivo characterization of a novel, highly potent p53-MDM2 inhibitor.

Bioorg Med Chem Lett 2018 11 26;28(20):3404-3408. Epub 2018 Aug 26.

Novartis Institutes for BioMedical Research, CH-4002 Basel, Switzerland.

Small molecule inhibitors of the p53-MDM2 protein complex are under intense investigation in clinical trials as anti-cancer agents, including our first generation inhibitor NVP-CGM097. We recently described the rational design of a novel pyrazolopyrrolidinone core as a new lead structure and now we report on the synthesis and optimization of this to provide a highly potent lead compound. This new compound displayed excellent oral efficacy in our preclinical mechanistic in vivo model and marked a significant milestone towards the identification of our second generation clinical candidate NVP-HDM201.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.bmcl.2018.08.027DOI Listing
November 2018

Dose and Schedule Determine Distinct Molecular Mechanisms Underlying the Efficacy of the p53-MDM2 Inhibitor HDM201.

Cancer Res 2018 11 22;78(21):6257-6267. Epub 2018 Aug 22.

Disease Area Oncology, Novartis Institutes for BioMedical Research, Cambridge, Massachusetts.

Activation of p53 by inhibitors of the p53-MDM2 interaction is being pursued as a therapeutic strategy in p53 wild-type cancers. Here, we report distinct mechanisms by which the novel, potent, and selective inhibitor of the p53-MDM2 interaction HDM201 elicits therapeutic efficacy when applied at various doses and schedules. Continuous exposure of HDM201 led to induction of p21 and delayed accumulation of apoptotic cells. By comparison, high-dose pulses of HDM201 were associated with marked induction of PUMA and a rapid onset of apoptosis. shRNA screens identified PUMA as a mediator of the p53 response specifically in the pulsed regimen. Consistent with this, the single high-dose HDM201 regimen resulted in rapid and marked induction of PUMA expression and apoptosis together with downregulation of Bcl-xL Knockdown of Bcl-xL was identified as the top sensitizer to HDM201 , and Bcl-xL was enriched in relapsing tumors from mice treated with intermittent high doses of HDM201. These findings define a regimen-dependent mechanism by which disruption of MDM2-p53 elicits therapeutic efficacy when given with infrequent dosing. In an ongoing HDM201 trial, the observed exposure-response relationship indicates that the molecular mechanism elicited by pulse dosing is likely reproducible in patients. These data support the clinical comparison of daily and intermittent regimens of p53-MDM2 inhibitors. Pulsed high doses versus sustained low doses of the p53-MDM2 inhibitor HDM201 elicit a proapoptotic response from wild-type p53 cancer cells, offering guidance to current clinical trials with this and other drugs that exploit the activity of p53. .
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1158/0008-5472.CAN-18-0338DOI Listing
November 2018

PDX-MI: Minimal Information for Patient-Derived Tumor Xenograft Models.

Cancer Res 2017 11;77(21):e62-e66

Greehey Children's Cancer Research Institute, University of Texas Health Science Center at San Antonio, San Antonio, Texas.

Patient-derived tumor xenograft (PDX) mouse models have emerged as an important oncology research platform to study tumor evolution, mechanisms of drug response and resistance, and tailoring chemotherapeutic approaches for individual patients. The lack of robust standards for reporting on PDX models has hampered the ability of researchers to find relevant PDX models and associated data. Here we present the PDX models minimal information standard (PDX-MI) for reporting on the generation, quality assurance, and use of PDX models. PDX-MI defines the minimal information for describing the clinical attributes of a patient's tumor, the processes of implantation and passaging of tumors in a host mouse strain, quality assurance methods, and the use of PDX models in cancer research. Adherence to PDX-MI standards will facilitate accurate search results for oncology models and their associated data across distributed repository databases and promote reproducibility in research studies using these models. .
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1158/0008-5472.CAN-17-0582DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5738926PMC
November 2017

Resistance mechanisms to TP53-MDM2 inhibition identified by in vivo piggyBac transposon mutagenesis screen in an Arf mouse model.

Proc Natl Acad Sci U S A 2017 03 6;114(12):3151-3156. Epub 2017 Mar 6.

Oncology Disease Area, Novartis Institutes for BioMedical Research, 4056 Basel, Switzerland.

Inhibitors of double minute 2 protein (MDM2)-tumor protein 53 (TP53) interaction are predicted to be effective in tumors in which the gene is wild type, by preventing TP53 protein degradation. One such setting is represented by the frequent deletion in human cancer that, through inactivation of , activates MDM2 protein, which in turn degrades TP53 tumor suppressor. Here we used piggyBac (PB) transposon insertional mutagenesis to anticipate resistance mechanisms occurring during treatment with the MDM2-TP53 inhibitor HDM201. Constitutive PB mutagenesis in mice provided a collection of spontaneous tumors with characterized insertional genetic landscapes. Tumors were allografted in large cohorts of mice to assess the pharmacologic effects of HDM201. Sixteen out of 21 allograft models were sensitive to HDM201 but ultimately relapsed under treatment. A comparison of tumors with acquired resistance to HDM201 and untreated tumors identified 87 genes that were differentially and significantly targeted by the PB transposon. Resistant tumors displayed a complex clonality pattern suggesting the emergence of several resistant subclones. Among the most frequent alterations conferring resistance, we observed somatic and insertional loss-of-function mutations in transformation-related protein 53 () in 54% of tumors and transposon-mediated gain-of-function alterations in B-cell lymphoma-extra large (), , and two family members, resulting in expression of the TP53 dominant negative truncations and Enhanced BCL-xL and MDM4 protein expression was confirmed in resistant tumors, as well as in HDM201-resistant patient-derived tumor xenografts. Interestingly, concomitant inhibition of MDM2 and BCL-xL demonstrated significant synergy in p53 wild-type cell lines in vitro. Collectively, our findings identify several potential mechanisms by which wild-type tumors may escape MDM2-targeted therapy.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1073/pnas.1620262114DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5373361PMC
March 2017

High-Order Drug Combinations Are Required to Effectively Kill Colorectal Cancer Cells.

Cancer Res 2016 12 22;76(23):6950-6963. Epub 2016 Sep 22.

Translational Clinical Oncology, Novartis Institutes for Biomedical Research, Cambridge, Massachusetts.

Like classical chemotherapy regimens used to treat cancer, targeted therapies will also rely upon polypharmacology, but tools are still lacking to predict which combinations of molecularly targeted drugs may be most efficacious. In this study, we used image-based proliferation and apoptosis assays in colorectal cancer cell lines to systematically investigate the efficacy of combinations of two to six drugs that target critical oncogenic pathways. Drug pairs targeting key signaling pathways resulted in synergies across a broad spectrum of genetic backgrounds but often yielded only cytostatic responses. Enhanced cytotoxicity was observed when additional processes including apoptosis and cell cycle were targeted as part of the combination. In some cases, where cell lines were resistant to paired and tripled drugs, increased expression of antiapoptotic proteins was observed, requiring a fourth-order combination to induce cytotoxicity. Our results illustrate how high-order drug combinations are needed to kill drug-resistant cancer cells, and they also show how systematic drug combination screening together with a molecular understanding of drug responses may help define optimal cocktails to overcome aggressive cancers. Cancer Res; 76(23); 6950-63. ©2016 AACR.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1158/0008-5472.CAN-15-3425DOI Listing
December 2016

High-throughput screening using patient-derived tumor xenografts to predict clinical trial drug response.

Nat Med 2015 Nov 19;21(11):1318-25. Epub 2015 Oct 19.

Oncology Disease Area, Novartis Institutes for Biomedical Research, Emeryville, California, USA.

Profiling candidate therapeutics with limited cancer models during preclinical development hinders predictions of clinical efficacy and identifying factors that underlie heterogeneous patient responses for patient-selection strategies. We established ∼1,000 patient-derived tumor xenograft models (PDXs) with a diverse set of driver mutations. With these PDXs, we performed in vivo compound screens using a 1 × 1 × 1 experimental design (PDX clinical trial or PCT) to assess the population responses to 62 treatments across six indications. We demonstrate both the reproducibility and the clinical translatability of this approach by identifying associations between a genotype and drug response, and established mechanisms of resistance. In addition, our results suggest that PCTs may represent a more accurate approach than cell line models for assessing the clinical potential of some therapeutic modalities. We therefore propose that this experimental paradigm could potentially improve preclinical evaluation of treatment modalities and enhance our ability to predict clinical trial responses.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/nm.3954DOI Listing
November 2015

Discovery of a Dihydroisoquinolinone Derivative (NVP-CGM097): A Highly Potent and Selective MDM2 Inhibitor Undergoing Phase 1 Clinical Trials in p53wt Tumors.

J Med Chem 2015 Aug 5;58(16):6348-58. Epub 2015 Aug 5.

Novartis Institutes for BioMedical Research , 4002 Basel, Switzerland.

As a result of our efforts to discover novel p53:MDM2 protein-protein interaction inhibitors useful for treating cancer, the potent and selective MDM2 inhibitor NVP-CGM097 (1) with an excellent in vivo profile was selected as a clinical candidate and is currently in phase 1 clinical development. This article provides an overview of the discovery of this new clinical p53:MDM2 inhibitor. The following aspects are addressed: mechanism of action, scientific rationale, binding mode, medicinal chemistry, pharmacokinetic and pharmacodynamic properties, and in vivo pharmacology/toxicology in preclinical species.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acs.jmedchem.5b00810DOI Listing
August 2015

A distinct p53 target gene set predicts for response to the selective p53-HDM2 inhibitor NVP-CGM097.

Elife 2015 May 12;4. Epub 2015 May 12.

Disease Area Oncology, Novartis Institutes for BioMedical Research, Basel, Switzerland.

Biomarkers for patient selection are essential for the successful and rapid development of emerging targeted anti-cancer therapeutics. In this study, we report the discovery of a novel patient selection strategy for the p53-HDM2 inhibitor NVP-CGM097, currently under evaluation in clinical trials. By intersecting high-throughput cell line sensitivity data with genomic data, we have identified a gene expression signature consisting of 13 up-regulated genes that predicts for sensitivity to NVP-CGM097 in both cell lines and in patient-derived tumor xenograft models. Interestingly, these 13 genes are known p53 downstream target genes, suggesting that the identified gene signature reflects the presence of at least a partially activated p53 pathway in NVP-CGM097-sensitive tumors. Together, our findings provide evidence for the use of this newly identified predictive gene signature to refine the selection of patients with wild-type p53 tumors and increase the likelihood of response to treatment with p53-HDM2 inhibitors, such as NVP-CGM097.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.7554/eLife.06498DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4468608PMC
May 2015

Characterization of the novel and specific PI3Kα inhibitor NVP-BYL719 and development of the patient stratification strategy for clinical trials.

Mol Cancer Ther 2014 May 7;13(5):1117-29. Epub 2014 Mar 7.

Authors' Affiliations: Novartis Institutes for BioMedical Research, Disease Area Oncology; Novartis Institutes for BioMedical Research, Global Discovery Chemistry; Novartis Institutes for BioMedical Research, Center for Proteomic Chemistry; Novartis Pharma AG, Oncology Translational Medicine, Basel, Switzerland; Novartis Pharma AG, Oncology Translational Medicine; Novartis Institutes for BioMedical Research, Developmental and Molecular Pathways, Cambridge, Massachusetts; and Novartis Institutes for BioMedical Research, Developmental and Molecular Pathways, Shangai, China.

Somatic PIK3CA mutations are frequently found in solid tumors, raising the hypothesis that selective inhibition of PI3Kα may have robust efficacy in PIK3CA-mutant cancers while sparing patients the side-effects associated with broader inhibition of the class I phosphoinositide 3-kinase (PI3K) family. Here, we report the biologic properties of the 2-aminothiazole derivative NVP-BYL719, a selective inhibitor of PI3Kα and its most common oncogenic mutant forms. The compound selectivity combined with excellent drug-like properties translates to dose- and time-dependent inhibition of PI3Kα signaling in vivo, resulting in robust therapeutic efficacy and tolerability in PIK3CA-dependent tumors. Novel targeted therapeutics such as NVP-BYL719, designed to modulate aberrant functions elicited by cancer-specific genetic alterations upon which the disease depends, require well-defined patient stratification strategies in order to maximize their therapeutic impact and benefit for the patients. Here, we also describe the application of the Cancer Cell Line Encyclopedia as a preclinical platform to refine the patient stratification strategy for NVP-BYL719 and found that PIK3CA mutation was the foremost positive predictor of sensitivity while revealing additional positive and negative associations such as PIK3CA amplification and PTEN mutation, respectively. These patient selection determinants are being assayed in the ongoing NVP-BYL719 clinical trials.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1158/1535-7163.MCT-13-0865DOI Listing
May 2014

Tumour T1 changes in vivo are highly predictive of response to chemotherapy and reflect the number of viable tumour cells--a preclinical MR study in mice.

BMC Cancer 2014 Feb 14;14:88. Epub 2014 Feb 14.

Oncology Research, Novartis Institutes for Biomedical Research, Basel, Switzerland.

Background: Effective chemotherapy rapidly reduces the spin-lattice relaxation of water protons (T1) in solid tumours and this change (ΔT1) often precedes and strongly correlates with the eventual change in tumour volume (TVol). To understand the biological nature of ΔT1, we have performed studies in vivo and ex vivo with the allosteric mTOR inhibitor, everolimus.

Methods: Mice bearing RIF-1 tumours were studied by magnetic resonance imaging (MRI) to determine TVol and T1, and MR spectroscopy (MRS) to determine levels of the proliferation marker choline and levels of lipid apoptosis markers, prior to and 5 days (endpoint) after daily treatment with vehicle or everolimus (10 mg/kg). At the endpoint, tumours were ablated and an entire section analysed for cellular and necrotic quantification and staining for the proliferation antigen Ki67 and cleaved-caspase-3 as a measure of apoptosis. The number of blood-vessels (BV) was evaluated by CD31 staining. Mice bearing B16/BL6 melanoma tumours were studied by MRI to determine T1 under similar everolimus treatment. At the endpoint, cell bioluminescence of the tumours was measured ex vivo.

Results: Everolimus blocked RIF-1 tumour growth and significantly reduced tumour T1 and total choline (Cho) levels, and increased polyunsaturated fatty-acids which are markers of apoptosis. Immunohistochemistry showed that everolimus reduced the %Ki67+ cells but did not affect caspase-3 apoptosis, necrosis, BV-number or cell density. The change in T1 (ΔT1) correlated strongly with the changes in TVol and Cho and %Ki67+. In B16/BL6 tumours, everolimus also decreased T1 and this correlated with cell bioluminescence; another marker of cell viability. Receiver-operating-characteristic curves (ROC) for everolimus on RIF-1 tumours showed that ΔT1 had very high levels of sensitivity and specificity (ROCAUC = 0.84) and this was confirmed for the cytotoxic patupilone in the same tumour model (ROCAUC = 0.97).

Conclusion: These studies suggest that ΔT1 is not a measure of cell density but reflects the decreased number of remaining viable and proliferating tumour cells due to perhaps cell and tissue destruction releasing proteins and/or metals that cause T1 relaxation. ΔT1 is a highly sensitive and specific predictor of response. This MRI method provides the opportunity to stratify a patient population during tumour therapy in the clinic.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/1471-2407-14-88DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3932835PMC
February 2014

M2 isoform of pyruvate kinase is dispensable for tumor maintenance and growth.

Proc Natl Acad Sci U S A 2013 Jan 24;110(2):489-94. Epub 2012 Dec 24.

Disease Area Oncology, Novartis Institutes for BioMedical Research, 4056 Basel, Switzerland.

Many cancer cells have increased rates of aerobic glycolysis, a phenomenon termed the Warburg effect. In addition, in tumors there is a predominance of expression of the M2 isoform of pyruvate kinase (PKM2). M2 expression was previously shown to be necessary for aerobic glycolysis and to provide a growth advantage to tumors. We report that knockdown of pyruvate kinase in tumor cells leads to a decrease in the levels of pyruvate kinase activity and an increase in the pyruvate kinase substrate phosphoenolpyruvate. However, lactate production from glucose, although reduced, was not fully inhibited. Furthermore, we are unique in reporting increased serine and glycine biosynthesis from both glucose and glutamine following pyruvate kinase knockdown. Although pyruvate kinase knockdown results in modest impairment of proliferation in vitro, in vivo growth of established xenograft tumors is unaffected by PKM2 absence. Our findings indicate that PKM2 is dispensable for tumor maintenance and growth in vivo, suggesting that other metabolic pathways bypass its function.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1073/pnas.1212780110DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3545759PMC
January 2013

Quantified tumor t1 is a generic early-response imaging biomarker for chemotherapy reflecting cell viability.

Clin Cancer Res 2010 Jan 15;16(1):212-25. Epub 2009 Dec 15.

Oncology Research and Global Imaging Group, Novartis Institutes for Biomedical Research, Basel, Switzerland.

Purpose: Identification of a generic response biomarker by comparison of chemotherapeutics with different action mechanisms on several noninvasive biomarkers in experimental tumor models.

Experimental Design: The spin-lattice relaxation time of water protons (T(1)) was quantified using an inversion recovery-TrueFISP magnetic resonance imaging method in eight different experimental tumor models before and after treatment at several different time points with five different chemotherapeutics. Effects on T(1) were compared with other minimally invasive biomarkers including vascular parameters, apparent diffusion coefficient, and interstitial fluid pressure, and were correlated with efficacy at the endpoint and histologic parameters.

Results: In all cases, successful chemotherapy significantly lowered tumor T(1) compared with vehicle and the fractional change in T(1) (DeltaT(1)) correlated with the eventual change in tumor size (range: r(2) = 0.21, P < 0.05 to r(2) = 0.73, P < 0.0001), except for models specifically resistant to that drug. In RIF-1 tumors, interstitial fluid pressure was decreased, but apparent diffusion coefficient and permeability increased in response to the microtubule stabilizer patupilone and 5-fluorouracil. Although DeltaT(1) was small (maximum of -20%), the variability was very low (5%) compared with other magnetic resonance imaging methods (24-48%). Analyses ex vivo showed unchanged necrosis, increased apoptosis, and decreased %Ki67 and total choline, but only Ki67 and choline correlated with DeltaT(1). Correlation of Ki67 and DeltaT(1) were observed in other models using patupilone, paclitaxel, a VEGF-R inhibitor, and the mammalian target of rapamycin inhibitor everolimus.

Conclusions: These results suggest that a decrease in tumor T(1) reflects hypocellularity and is a generic marker of response. The speed and robustness of the method should facilitate its use in clinical trials.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1158/1078-0432.CCR-09-0686DOI Listing
January 2010

Tumor interstitial fluid pressure as an early-response marker for anticancer therapeutics.

Neoplasia 2009 Sep;11(9):874-81

Oncology Research, Novartis Institute of Biomedical Research, 4002 Basel, Switzerland.

Solid tumors have a raised interstitial fluid pressure (IFP) due to high vessel permeability, low lymphatic drainage, poor perfusion, and high cell density around the blood vessels. To investigate tumor IFP as an early-response biomarker, we have tested the effect of seven anticancer chemotherapeutics including cytotoxics and targeted cytostatics in 13 experimental tumor models. IFP was recorded with the wick-in-needle method. Models were either ectopic or orthotopic and included mouse and rat syngeneic as well as human xenografts in nude mice. The mean basal IFP was between 4.4 and 15.2mm Hg; IFP was lowest in human tumor xenografts and highest in rat syngeneic models. Where measured, basal IFP correlated positively with relative tumor blood volume (rTBV) determined by dynamic contrast-enhanced magnetic resonance imaging. Most chemotherapeutics sooner (2 or 3 days) or later (6 or 7 days) lowered tumor IFP significantly, and the cytotoxic patupilone caused the greatest decrease in IFP. In rat mammary orthotopic BN472 tumors, significant drug-induced decreases in IFP and rTBV correlated positively with each other for both patupilone and the cytostatic vatalanib. In the two orthotopic models studied, early decreases in IFP were significantly (P < or = .005) correlated with late changes in tumor volume. Thus, drug-induced decreases in tumor IFP are an early marker of response to therapy, which could aid clinical development.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1593/neo.09554DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2735799PMC
September 2009

Effect of adenosine A2A receptor activation in murine models of respiratory disorders.

Am J Physiol Lung Cell Mol Physiol 2006 May 9;290(5):L1036-43. Epub 2005 Dec 9.

Respiratory Diseases Area, Novartis Institutes for BioMedical Research, Horsham, England, UK.

Activation of the adenosine A(2A) receptor has been postulated as a possible treatment for lung inflammatory diseases such as asthma and chronic obstructive pulmonary disease (COPD). In this report, we have studied the anti-inflammatory properties of the reference A(2A) agonist CGS-21680, given intranasally at doses of 10 and 100 microg/kg, in a variety of murine models of asthma and COPD. After an acute ovalbumin challenge of sensitized mice, prophylactic administration of CGS-21680 inhibited the bronchoalveolar lavage fluid inflammatory cell influx but not the airway hyperreactivity to aerosolized methacholine. After repeated ovalbumin challenges, CGS-21680 given therapeutically inhibited the bronchoalveolar lavage fluid inflammatory cell influx but had no effect on the allergen-induced bronchoconstriction, the airway hyperreactivity, or the bronchoalveolar lavage fluid mucin levels. As a comparator, budesonide given intranasally at doses of 0.1-1 mg/kg fully inhibited all the parameters measured in the latter model. In a lipopolysaccharide-driven model, CGS-21680 had no effect on the bronchoalveolar lavage fluid inflammatory cell influx or TNF-alpha, keratinocyte chemoattractant, and macrophage inflammatory protein-2 levels, but potently inhibited neutrophil activation, as measured by bronchoalveolar lavage fluid elastase levels. With the use of a cigarette smoke model of lung inflammation, CGS-21680 did not significantly inhibit bronchoalveolar lavage fluid neutrophil infiltration but reversed the cigarette smoke-induced decrease in macrophage number. Together, these results suggest that activation of the A(2A) receptor would have a beneficial effect by inhibiting inflammatory cell influx and downregulating inflammatory cell activation in asthma and COPD, respectively.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1152/ajplung.00422.2005DOI Listing
May 2006

Patupilone induced vascular disruption in orthotopic rodent tumor models detected by magnetic resonance imaging and interstitial fluid pressure.

Clin Cancer Res 2005 Nov;11(21):7773-84

Oncology Research, Novartis Institutes for BioMedical Research, Basel, Switzerland.

Purpose: Evaluation of vascular disruptive activity in orthotopic models as potential surrogate biomarkers of tumor response to the microtubule-stabilizing agent patupilone.

Experimental Design: Mice bearing metastatic B16/BL6 melanoma and rats bearing mammary BN472 tumors received vehicle or efficacious patupilone doses (4 and 0.8-1.5 mg/kg i.v., respectively). Tumor vascularity assessment by dynamic contrast-enhanced or dynamic susceptibility contrast magnetic resonance imaging and interstitial fluid pressure (IFP) occurred at baseline, 2 days (mice and rats), and 6 days (rats) after treatment and were compared with histologic measurements and correlated with tumor response.

Results: In B16/BL6 metastases, patupilone (4 mg/kg) induced a 21 +/- 5% decrease (P < 0.001) in tumor blood volume and a 32 +/- 15% decrease (P = 0.02) in IFP after 2 days and reduced tumor growth and vessel density (>42%) after 2 weeks (P < or = 0.014). Patupilone dose-dependently inhibited BN472 tumor growth (day 6) and reduced IFP on days 2 and 6 (-21% to -70%), and the percentage change in IFP correlated (P < 0.01) with the change in tumor volume. In both models, histology and vascular casts confirmed decreases in tumor blood volume. One patupilone (0.8 mg/kg) administration decreased (P < 0.01) tumor IFP (54 +/- 4%), tumor blood volume (50 +/- 6%), and vessel diameter (40 +/- 11%) by day 6 but not the apparent diffusion coefficient, whereas histology showed that apoptosis was increased 2.4-fold and necrosis was unchanged. Apoptosis correlated negatively (P < 0.001) with IFP, tumor blood volume, and tumor volume, whereas tumor blood volume and IFP were correlated positively (P = 0.0005).

Conclusions: Vascular disruptive effects of patupilone were detected in situ using dynamic contrast-enhanced or dynamic susceptibility contrast magnetic resonance imaging and IFP. Changes in IFP preceded and correlated with tumor response, suggesting that IFP may be a surrogate biomarker for patupilone efficacy.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1158/1078-0432.CCR-05-1165DOI Listing
November 2005

PTK787/ZK222584, a tyrosine kinase inhibitor of vascular endothelial growth factor receptor, reduces uptake of the contrast agent GdDOTA by murine orthotopic B16/BL6 melanoma tumours and inhibits their growth in vivo.

NMR Biomed 2005 Aug;18(5):308-21

Discovery Technology, Novartis Pharma AG, CH-4002 Basel, Switzerland.

Assessment of tumour vascularity may characterize malignancy as well as predict responsiveness to anti-angiogenic therapy. Non-invasive measurement of tumour perfusion and blood vessel permeability assessed as the transfer constant, K(trans), can be provided by dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). Using the orthotopic murine tumour model B16/BL6 melanoma, the small contrast agent GdDOTA (DOTAREM(R); Guerbet, Paris) was applied to assess the vascular transfer constant, K(trans), and interstitial leakage space, whereas intravascular iron oxide nanoparticles (Endorem(R); Guerbet, Paris) were used to detect relative tumour blood volume (rTBV), and in one experiment blood flow index (BFI). No correlations were observed between these four parameters (r(2) always <0.05). The B16/BL6 primary tumour and lymph-node cervical (neck) metastases produced high levels of the permeability/growth factor, VEGF. To probe the model, the novel VEGF receptor (VEGF-R) tyrosine kinase inhibitor, PTK787/ZK222584 (PTK/ZK) was tested for anti-tumour efficacy and its effects on DCE-MRI measured parameters of tumour vascularity. Data from the non-invasive measure of tumour vascularity were compared with a histological measurement of vasculature using the DNA-staining dye H33342. PTK/ZK inhibited growth of the primary and, particularly, cervical tumour metastases following chronic treatment for 2 weeks (50 or 100 mg/kg daily) of 1-week-old tumours, or with 1 week of treatment against more established (2-week-old) tumours. After chronic treatment with PTK/ZK, DCE-MRI detected significant decreases in K(trans) and interstitial leakage space, but not rTBV of both primary tumours and cervical metastases. Histological data at this time-point showed a significant decrease in blood vessel density of the cervical metastases but not the primary tumours. However, in the cervical metastases, the mean blood vessel width was increased by 38%, suggesting overall no marked change in blood volume. After acute (2-4 day) treatment, DCE-MRI of the cervical metastases demonstrated a significant decrease in K(trans) and interstitial leakage space and also in the initial area under the enhancement curve for GdDOTA (IAUC), but no change in the rTBV or BFI. Thus, significant changes could be detected in the DCE-MRI measurement of tumour uptake of a small contrast agent prior to changes in tumour size, which suggests that DCE-MRI could be applied in the clinic as a rapid and sensitive biomarker for the effects of VEGF-R inhibition on tumour blood vessel permeability and thus may provide an early marker for eventual tumour response.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/nbm.961DOI Listing
August 2005

Differential DNA synthesis in response to activation of protease-activated receptors on cultured guinea-pig tracheal smooth muscle cells.

Naunyn Schmiedebergs Arch Pharmacol 2003 Jul 18;368(1):10-6. Epub 2003 Jun 18.

Novartis Respiratory Research Centre, Wimblehurst Road, Horsham, RH12 5AB, UK.

Both thrombin and tryptase have been shown to induce smooth muscle cell proliferation in vitro. We have used cultured primary guinea-pig tracheal smooth muscle in order to define pharmacologically the receptors involved in this effect. Tryptase, a protease-activated receptor (PAR)-2 agonist, induced DNA synthesis up to the second passage of the cells, thereafter the response waned. In contrast, thrombin, a PAR-1 agonist, and the PAR-1 activating peptide (SFLLRN) induced DNA synthesis starting from the third passage only. Thrombin and tryptase responses were dose-dependently inhibited by leupeptin. The selective PAR-2 activating peptide (SLIGRL-NH(2)) was unable to induce DNA synthesis in cells from passages 1 to 6. In agreement with the functional data, mRNA expression for PAR-1 was increased in cells in later passages. In contradiction with the functional data, however, equal mRNA expression for PAR-2 was found in all passages. These results suggest that thrombin induces guinea-pig tracheal smooth muscle DNA synthesis through activation of PAR-1. However, the differential effect of tryptase and SLIGRL-NH(2) suggests that tryptase might exert some of its effect via a non-PAR-2 receptor.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00210-003-0765-9DOI Listing
July 2003

IL-17, produced by lymphocytes and neutrophils, is necessary for lipopolysaccharide-induced airway neutrophilia: IL-15 as a possible trigger.

J Immunol 2003 Feb;170(4):2106-12

Novartis Respiratory Research Center, Wimblehurst Road, RH12 5 AB Horsham, UK.

IL-17 is a cytokine implicated in the regulation of inflammation. We investigated the role of this cytokine in neutrophil recruitment using a model of LPS-induced lung inflammation in mice. In the bronchoalveolar lavage, LPS induced a first influx of neutrophils peaking at day 1, followed by a second wave, peaking at day 2. IL-17 levels were increased during the late phase neutrophilia (day 2), and this was concomitant with an increased number of T cells and macrophages, together with an increase of KC and macrophage-inflammatory protein-2 levels in the lung tissue. Intranasal treatment with a neutralizing murine anti-IL-17 Ab inhibited the late phase neutrophilia. In the bronchoalveolar lavage cells, IL-17 mRNA was detected at days 1, 2, and 3 postchallenge, with a strong expression at day 2. This expression was associated with CD4(+) and CD8(+) cells, but also with neutrophils. When challenged with LPS, despite the absence of T cells, SCID mice also developed a neutrophilic response associated with IL-17 production. In BALB/c mice, IL-15 mRNA, associated mainly with neutrophils, was evidenced 1 day after LPS challenge. In vitro, IL-15 was able to induce IL-17 release from purified spleen CD4(+) cells, but not spleen CD8(+) or airway neutrophils. We have shown that IL-17, produced mainly by CD4(+) cells, but also by neutrophils, plays a role in the mobilization of lung neutrophils following bacterial challenge. In addition, our results suggest that IL-15 could represent a physiological trigger that leads to IL-17 production following bacterial infection.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.4049/jimmunol.170.4.2106DOI Listing
February 2003
-->