Publications by authors named "Erica A Golemis"

142 Publications

Delineating The RAS Conformational Landscape.

Cancer Res 2022 May 10. Epub 2022 May 10.

Fox Chase Cancer Center, Philadelphia, PA, United States.

Mutations in RAS isoforms (KRAS, NRAS, and HRAS) are among the most frequent oncogenic alterations in many cancers, making these proteins high priority therapeutic targets. Effectively targeting RAS isoforms requires an exact understanding of their active, inactive, and druggable conformations. However, there is no structural catalog of RAS conformations to guide therapeutic targeting or examining the structural impact of RAS mutations. Here we present an expanded classification of RAS conformations based on analyses of the catalytic switch 1 (SW1) and switch 2 (SW2) loops. From 721 human KRAS, NRAS, and HRAS structures available in the Protein Data Bank (206 RAS-protein co-complexes, 190 inhibitor-bound, and 325 unbound, including 204 WT and 517 mutated structures), we created a broad conformational classification based on the spatial positions of Y32 in SW1 and Y71 in SW2. Clustering all well-modeled SW1 and SW2 loops using a density-based machine learning algorithm defined additional conformational subsets, some previously undescribed. Three SW1 conformations and nine SW2 conformations were identified, each associated with different nucleotide states (GTP-bound, nucleotide-free, and GDP-bound) and specific bound proteins or inhibitor sites. The GTP-bound SW1 conformation could be further subdivided based on the hydrogen bond type made between Y32 and the GTP γ-phosphate. Further analysis clarified the catalytic impact of G12D and G12V mutations and the inhibitor chemistries that bind to each druggable RAS conformation. Overall, this study has expanded our understanding of RAS structural biology, which could facilitate future RAS drug discovery.
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http://dx.doi.org/10.1158/0008-5472.CAN-22-0804DOI Listing
May 2022

Association of TP53 and CDKN2A Mutation Profile with Tumor Mutation Burden in Head and Neck Cancer.

Clin Cancer Res 2022 May;28(9):1925-1937

Molecular Therapeutics Program, Fox Chase Cancer Center, Philadelphia, Pennsylvania.

Purpose: Head and neck squamous cell carcinoma (HNSCC) is a frequently devastating cancer that affects more than a half million people annually worldwide. Although some cases arise from infection with human papillomavirus (HPV), HPV-negative HNSCC is more common, and associated with worse outcome. Advanced HPV-negative HNSCC may be treated with surgery, chemoradiation, targeted therapy, or immune checkpoint inhibition (ICI). There is considerable need for predictive biomarkers for these treatments. Defects in DNA repair capacity and loss of cell-cycle checkpoints sensitize tumors to cytotoxic therapies, and can contribute to phenotypes such as elevated tumor mutation burden (TMB), associated with response to ICI. Mutation of the tumor suppressors and checkpoint mediators TP53 and CDKN2A is common in HPV-negative HNSCC.

Experimental Design: To gain insight into the relation of the interaction of TP53 and CDKN2A mutations with TMB in HNSCC, we have analyzed genomic data from 1,669 HPV-negative HNSCC tumors with multiple criteria proposed for assessing the damaging effect of TP53 mutations.

Results: Data analysis established the TP53 and CDKN2A mutation profiles in specific anatomic subsites and suggested that specific categories of TP53 mutations are more likely to associate with CDKN2A mutation or high TMB based on tumor subsite. Intriguingly, the pattern of hotspot mutations in TP53 differed depending on the presence or absence of a cooccurring CDKN2A mutation.

Conclusions: These data emphasize the role of tumor subsite in evaluation of mutational profiles in HNSCC, and link defects in TP53 and CDKN2A to elevated TMB levels in some tumor subgroups.
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http://dx.doi.org/10.1158/1078-0432.CCR-21-4316DOI Listing
May 2022

NEDD9 sustains hexokinase expression to promote glycolysis.

Oncogenesis 2022 Apr 11;11(1):15. Epub 2022 Apr 11.

Program in Molecular Therapeutics, Fox Chase Cancer Center, Philadelphia, PA, 19111, USA.

Elevated rates of glycolysis in cancer cells support tumor growth, in a process that typically depends on oncogene-induced increases in the expression and/or activity of enzymes in the glycolytic pathway. The NEDD9 scaffolding protein is upregulated in many advanced tumors, with increased NEDD9 promoting the activity of SRC and other effectors that promote invasion and metastasis. We here define a new role for NEDD9 in support of glycolysis. NEDD9 knockdown significantly impaired glycolysis in multiple lung cancer cell lines This was accompanied by post-transcriptional downregulation of steady-state levels of hexokinases (HK1 and HK2), which catalyze early steps in the glycolytic cascade, key rate limiting enzyme phosphofructokinase (PFK1), and downstream glyceraldehyde phosphate dehydrogenase (GAPDH). In mice, protein levels of HK1, HK2, PFK1, and GAPDH were depressed in Kras /Trp53 (KP) non-small cell lung tumors with null versus wild type Nedd9. Reciprocally, depletion of HK1 or HK2 elevated NEDD9 expression, as did the treatment of cells with 2-deoxyglucose (2DG), an inhibitor of glycolysis; whereas overexpression of hexokinases promoted NEDD9 dephosphorylation, associated with reduced NEDD9 activity. Together, these data for the first time suggest a negative feedback circuit involving NEDD9 and glycolytic enzymes that may contribute to NEDD9 action in promoting the aggressive growth of advanced tumors.
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http://dx.doi.org/10.1038/s41389-022-00391-wDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9001639PMC
April 2022

Comprehensive characterization of PTEN mutational profile in a series of 34,129 colorectal cancers.

Nat Commun 2022 03 25;13(1):1618. Epub 2022 Mar 25.

Program in Molecular Therapeutics, Fox Chase Cancer Center, Philadelphia, PA, 19111, USA.

Loss of expression or activity of the tumor suppressor PTEN acts similarly to an activating mutation in the oncogene PIK3CA in elevating intracellular levels of phosphatidylinositol (3,4,5)-trisphosphate (PIP3), inducing signaling by AKT and other pro-tumorigenic signaling proteins. Here, we analyze sequence data for 34,129 colorectal cancer (CRC) patients, capturing 3,434 PTEN mutations. We identify specific patterns of PTEN mutation associated with microsatellite stability/instability (MSS/MSI), tumor mutational burden (TMB), patient age, and tumor location. Within groups separated by MSS/MSI status, this identifies distinct profiles of nucleotide hotspots, and suggests differing profiles of protein-damaging effects of mutations. Moreover, discrete categories of PTEN mutations display non-identical patterns of co-occurrence with mutations in other genes important in CRC pathogenesis, including KRAS, APC, TP53, and PIK3CA. These data provide context for clinical targeting of proteins upstream and downstream of PTEN in distinct CRC cohorts.
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http://dx.doi.org/10.1038/s41467-022-29227-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8956741PMC
March 2022

HSP90 inhibition downregulates DNA replication and repair genes via E2F1 repression.

J Biol Chem 2021 08 21;297(2):100996. Epub 2021 Jul 21.

School of Life Sciences, Jiangsu University, Zhenjiang, Jiangsu, China. Electronic address:

Mantle cell lymphoma (MCL) is an especially aggressive and highly heterogeneous mature B-cell lymphoma. Heat shock protein 90 (HSP90) is considered an attractive therapeutic target in a variety of cancers, including MCL, but no HSP90 inhibitors have succeeded in the clinical trials to date. Exploring fine mechanisms of HSP90 inhibition in cancer cells may shed light on novel therapeutic strategies. Here, we found that HSP90 knockdown and continuous inhibition with ganetespib inhibited growth of MCL cells in vitro and in vivo. To our surprise, transient exposure over 12 h was almost as efficient as continuous exposure, and treatment with ganetespib for 12 h efficiently inhibited growth and induced G1 cell cycle arrest and apoptosis of MCL cells. Transcriptome analysis complemented by functional studies was performed to define critical MCL signaling pathways that are exceptionally sensitive to HSP90 inhibition and vital to cell fate. Six genes (cell division cycle 6, cell division cycle 45, minichromosome maintenance 4, minichromosome maintenance 7, RecQ-mediated genome instability 2, and DNA primase polypeptide 1) involved in DNA replication and repair were identified as consistently downregulated in three MCL cell lines after transient ganetespib treatment. E2F1, an important transcription factor essential for cell cycle progression, was identified as a ganetespib target mediating transcriptional downregulation of these six genes, and its stability was also demonstrated to be maintained by HSP90. This study identifies E2F1 as a novel client protein of HSP90 that is very sensitive and worthy of targeting and also finds that HSP90 inhibitors may be useful in combination therapies for MCL.
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http://dx.doi.org/10.1016/j.jbc.2021.100996DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8363837PMC
August 2021

Evaluation of the Small-molecule BRD4 Degrader CFT-2718 in Small-cell Lung Cancer and Pancreatic Cancer Models.

Mol Cancer Ther 2021 08 27;20(8):1367-1377. Epub 2021 May 27.

Program in Molecular Therapeutics, Fox Chase Cancer Center, Philadelphia, Pennsylvania.

Targeted, catalytic degradation of oncoproteins using heterobifunctional small molecules is an attractive modality, particularly for hematologic malignancies, which are often initiated by aberrant transcription factors and are challenging to drug with inhibitors. BRD4, a member of the bromodomain and extraterminal family, is a core transcriptional and epigenetic regulator that recruits the P-TEFb complex, which includes Cdk9 and cyclin T, to RNA polymerase II (pol II). Together, BRD4 and CDK9 phosphorylate serine 2 (pSer2) of heptad repeats in the C-terminal domain of RPB1, the large subunit of pol II, promote transcriptional elongation. Small-molecule degraders of BRD4 have shown encouraging efficacy in preclinical models for several tumor types but less efficacy in other cancers including small-cell lung cancer (SCLC) and pancreatic cancer. Here, we evaluated CFT-2718, a new BRD4-targeting degrader with enhanced catalytic activity and in vivo properties. , CFT-2718 has significantly greater efficacy than the CDK9 inhibitor dinaciclib in reducing growth of the LX-36 SCLC patient-derived xenograft (PDX) model and performed comparably to dinaciclib in limiting growth of the PNX-001 pancreatic PDX model. , CFT-2718 reduced cell viability in four SCLC and two pancreatic cancer models. In SCLC models, this activity significantly exceeded that of dinaciclib; furthermore, CFT-2718 selectively increased the expression of cleaved PARP, an indicator of apoptosis. CFT-2718 caused rapid BRD4 degradation and reduced levels of total and pSer2 RPB1 protein. These and other findings suggest that BRD-mediated transcriptional suppression merits further exploration in the setting of SCLC.
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http://dx.doi.org/10.1158/1535-7163.MCT-20-0831DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8338762PMC
August 2021

Restrains Autophagy to Limit Growth of Early Stage Non-Small Cell Lung Cancer.

Cancer Res 2021 07 18;81(13):3717-3726. Epub 2021 May 18.

Program in Molecular Therapeutics Fox Chase Cancer Center, Philadelphia, PA.

Non-small cell lung cancer (NSCLC) is the most common cancer worldwide. With overall 5-year survival estimated at <17%, it is critical to identify factors that regulate NSCLC disease prognosis. NSCLC is commonly driven by mutations in and , with activation of additional kinases such as SRC promoting tumor invasion. In this study, we investigated the role of NEDD9, a SRC activator and scaffolding protein, in NSCLC tumorigenesis. In an inducible model of NSCLC dependent on mutation and loss ( mice), deletion of ( mice) led to the emergence of larger tumors characterized by accelerated rates of tumor growth and elevated proliferation. Orthotopic injection of and tumors into the lungs of -wild-type and -null mice indicated the effect of loss was cell-autonomous. Tumors in mice displayed reduced activation of SRC and AKT, indicating that activation of these pathways did not mediate enhanced growth of KPN tumors. NSCLC tumor growth has been shown to require active autophagy, a process dependent on activation of the kinases LKB1 and AMPK. tumors contained high levels of active LKB1 and AMPK and increased autophagy compared with tumors. Treatment with the autophagy inhibitor chloroquine completely eliminated the growth advantage of KPN tumors. These data for the first time identify NEDD9 as a negative regulator of LKB1/AMPK-dependent autophagy during early NSCLC tumor growth. SIGNIFICANCE: This study demonstrates a novel role for the scaffolding protein NEDD9 in regulating LKB1-AMPK signaling in early stage non-small cell lung cancer, suppressing autophagy and tumor growth.
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http://dx.doi.org/10.1158/0008-5472.CAN-20-3626DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8277748PMC
July 2021

Musashi-2 (MSI2) regulates epidermal growth factor receptor (EGFR) expression and response to EGFR inhibitors in EGFR-mutated non-small cell lung cancer (NSCLC).

Oncogenesis 2021 Mar 15;10(3):29. Epub 2021 Mar 15.

Molecular Therapeutics Program, Fox Chase Cancer Center, 333 Cottman Avenue, Philadelphia, PA, 19111, USA.

Non-small cell lung cancer (NSCLC) has limited treatment options. Expression of the RNA-binding protein (RBP) Musashi-2 (MSI2) is elevated in a subset of non-small cell lung cancer (NSCLC) tumors upon progression, and drives NSCLC metastasis. We evaluated the mechanism of MSI2 action in NSCLC to gain therapeutically useful insights. Reverse phase protein array (RPPA) analysis of MSI2-depleted versus control Kras; Trp53 NSCLC cell lines identified EGFR as a MSI2-regulated protein. MSI2 control of EGFR expression and activity in an NSCLC cell line panel was studied using RT-PCR, Western blots, and RNA immunoprecipitation. Functional consequences of MSI2 depletion were explored for cell growth and response to EGFR-targeting drugs, in vitro and in vivo. Expression relationships were validated using human tissue microarrays. MSI2 depletion significantly reduced EGFR protein expression, phosphorylation, or both. Comparison of protein and mRNA expression indicated a post-transcriptional activity of MSI2 in control of steady state levels of EGFR. RNA immunoprecipitation analysis demonstrated that MSI2 directly binds to EGFR mRNA, and sequence analysis predicted MSI2 binding sites in the murine and human EGFR mRNAs. MSI2 depletion selectively impaired cell proliferation in NSCLC cell lines with activating mutations of EGFR (EGFR). Further, depletion of MSI2 in combination with EGFR inhibitors such as erlotinib, afatinib, and osimertinib selectively reduced the growth of EGFR NSCLC cells and xenografts. EGFR and MSI2 were significantly co-expressed in EGFR human NSCLCs. These results define MSI2 as a direct regulator of EGFR protein expression, and suggest inhibition of MSI2 could be of clinical value in EGFR NSCLC.
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http://dx.doi.org/10.1038/s41389-021-00317-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7961039PMC
March 2021

Cholesterol Pathway Inhibition Induces TGF-β Signaling to Promote Basal Differentiation in Pancreatic Cancer.

Cancer Cell 2020 10 24;38(4):567-583.e11. Epub 2020 Sep 24.

Molecular Therapeutics Program, Fox Chase Cancer Center, 333 Cottman Avenue, Philadelphia, PA 19111, USA; The Marvin & Concetta Greenberg Pancreatic Cancer Institute, Fox Chase Cancer Center, Philadelphia, PA, USA; Kazan Federal University, Kazan, Russian Federation. Electronic address:

Oncogenic transformation alters lipid metabolism to sustain tumor growth. We define a mechanism by which cholesterol metabolism controls the development and differentiation of pancreatic ductal adenocarcinoma (PDAC). Disruption of distal cholesterol biosynthesis by conditional inactivation of the rate-limiting enzyme Nsdhl or treatment with cholesterol-lowering statins switches glandular pancreatic carcinomas to a basal (mesenchymal) phenotype in mouse models driven by Kras expression and homozygous Trp53 loss. Consistently, PDACs in patients receiving statins show enhanced mesenchymal features. Mechanistically, statins and NSDHL loss induce SREBP1 activation, which promotes the expression of Tgfb1, enabling epithelial-mesenchymal transition. Evidence from patient samples in this study suggests that activation of transforming growth factor β signaling and epithelial-mesenchymal transition by cholesterol-lowering statins may promote the basal type of PDAC, conferring poor outcomes in patients.
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http://dx.doi.org/10.1016/j.ccell.2020.08.015DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7572882PMC
October 2020

Prevalence of pathogenic variants in DNA damage response and repair genes in patients undergoing cancer risk assessment and reporting a personal history of early-onset renal cancer.

Sci Rep 2020 08 11;10(1):13518. Epub 2020 Aug 11.

Cancer Prevention and Control Program, Fox Chase Cancer Center, 333 Cottman Avenue, Philadelphia, PA, 19111-2497, USA.

Pathogenic variants (PVs) in multiple genes are known to increase the risk of early-onset renal cancer (eoRC). However, many eoRC patients lack PVs in RC-specific genes; thus, their genetic risk remains undefined. Here, we determine if PVs in DNA damage response and repair (DDRR) genes are enriched in eoRC patients undergoing cancer risk assessment. Retrospective review of de-identified results from 844 eoRC patients, undergoing testing with a multi-gene panel, for a variety of indications, by Ambry Genetics. PVs in cancer-risk genes were identified in 12.8% of patients-with 3.7% in RC-specific, and 8.55% in DDRR genes. DDRR gene PVs were most commonly identified in CHEK2, BRCA1, BRCA2, and ATM. Among the 2.1% of patients with a BRCA1 or BRCA2 PV, < 50% reported a personal history of hereditary breast or ovarian-associated cancer. No association between age of RC diagnosis and prevalence of PVs in RC-specific or DDRR genes was observed. Additionally, 57.9% patients reported at least one additional cancer; breast cancer being the most common (40.1% of females, 2.5% of males). Multi-gene testing including DDRR genes may provide a more comprehensive risk assessment in eoRC patients. Further validation is needed to characterize the association with eoRC.
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http://dx.doi.org/10.1038/s41598-020-70449-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7419503PMC
August 2020

Patterns of Ciliation and Ciliary Signaling in Cancer.

Rev Physiol Biochem Pharmacol 2020 Aug 7. Epub 2020 Aug 7.

Program in Molecular Therapeutics, Fox Chase Cancer Center, Philadelphia, PA, USA.

Among the factors that have been strongly implicated in regulating cancerous transformation, the primary monocilium (cilium) has gained increasing attention. The cilium is a small organelle extending from the plasma membrane, which provides a localized hub for concentration of transmembrane receptors. These receptors transmit signals from soluble factors (including Sonic hedgehog (SHH), platelet-derived growth factor (PDGF-AA), WNT, TGFβ, NOTCH, and others) that regulate cell growth, as well as mechanosensory cues provided by flow or extracellular matrix. Ciliation is regulated by cell cycle, with most cells that are in G0 (quiescent) or early G1 ciliation and cilia typically absent in G2/M cells. Notably, while most cells organized in solid tissues are ciliated, cancerous transformation induces significant changes in ciliation. Most cancer cells lose cilia; medulloblastomas and basal cell carcinomas, dependent on an active SHH pathway, rely on ciliary maintenance. Changes in cancer cell ciliation are driven by core oncogenic pathways (EGFR, KRAS, AURKA, PI3K), and importantly ciliation status regulates functionality of those pathways. Ciliation is both influenced by targeted cancer therapies and linked to therapeutic resistance; recent studies suggest ciliation may also influence cancer cell metabolism and stem cell identity. We review recent studies defining the relationship between cilia and cancer.
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http://dx.doi.org/10.1007/112_2020_36DOI Listing
August 2020

X- and Y-Linked Chromatin-Modifying Genes as Regulators of Sex-Specific Cancer Incidence and Prognosis.

Clin Cancer Res 2020 11 30;26(21):5567-5578. Epub 2020 Jul 30.

Molecular Therapeutics Program, Fox Chase Cancer Center, Philadelphia, Pennsylvania.

Biological sex profoundly conditions organismal development and physiology, imposing wide-ranging effects on cell signaling, metabolism, and immune response. These effects arise from sex-specified differences in hormonal exposure, and from intrinsic genetic and epigenetic differences associated with the presence of an XX versus XY chromosomal complement. In addition, biological sex is now recognized to be a determinant of the incidence, presentation, and therapeutic response of multiple forms of cancer, including cancers not specifically associated with male or female anatomy. Although multiple factors contribute to sex-based differences in cancer, a growing body of research emphasizes a role for differential activity of X- and Y-linked tumor-suppressor genes in males and females. Among these, the X-linked and , and their Y-linked paralogs / and encode lysine demethylases. These epigenetic modulators profoundly influence gene expression, based on enzymatic activity in demethylating H3K27me3 and H3K4me3, and nonenzymatic scaffolding roles for large complexes that open and close chromatin for transcription. In a growing number of cases, mutations affecting these proteins have been recognized to strongly influence cancer risk, prognosis, and response to specific therapies. However, sex-specific patterns of mutation, expression, and activity of these genes, coupled with tissue-specific requirement for their function as tumor suppressors, together exemplify the complex relationship between sex and cancer vulnerabilities. In this review, we summarize and discuss the current state of the literature on the roles of these proteins in contributing to sex bias in cancer, and the status of clinical agents relevant to their function.
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http://dx.doi.org/10.1158/1078-0432.CCR-20-1741DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7642178PMC
November 2020

Identification of the KRIT1 Protein by LexA-Based Yeast Two-Hybrid System.

Methods Mol Biol 2020 ;2152:269-289

Molecular Therapeutics Program, Fox Chase Cancer Center, Philadelphia, PA, USA.

Cerebral cavernous malformation (CCM) is a vascular malformation of the central nervous system that is associated with leaky capillaries, and a predisposition to serious clinical conditions including intracerebral hemorrhage and seizures. Germline or sporadic mutations in the CCM1/KRIT1 gene are responsible for the majority of cases of CCM. In this article, we describe the original characterization of the CCM1/KRIT1 gene. This cloning was done through the use of a variant of the yeast two-hybrid screen known as the interaction trap, using the RAS-family GTPase KREV1/RAP1A as a bait. The partial clone of KRIT1 (Krev1 Interaction Trapped) initially identified was extended through 5'RACE and computational analysis to obtain a full-length cDNA, then used in a sequential screen to define the integrin-associated ICAP1 protein as a KRIT1 partner protein. We discuss how these interactions are relevant to the current understanding of KRIT1/CCM1 biology, and provide a protocol for library screening with the Interaction Trap.
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http://dx.doi.org/10.1007/978-1-0716-0640-7_20DOI Listing
March 2021

RNA interference screening methods to identify proliferation determinants and mechanisms of resistance to immune attack.

Methods Enzymol 2020 3;636:299-322. Epub 2019 Jul 3.

Lombardi Comprehensive Cancer Center, Georgetown University, Washington, DC, United States. Electronic address:

We have used RNA interference (RNAi) screening technology to reveal unknown components of biological signaling pathways including survival mechanisms of estrogen-independent breast cancer cell growth and cancer cell resistance to immune attack. In this chapter, a detailed protocol describing the use of RNAi screening to identify factors important for the proliferation of estrogen-independent MCF7 breast cancer cells will be described. Resistance to therapies that target the estrogen pathway remains a challenge in the treatment of estrogen receptor-positive breast cancer. To address this challenge, small interfering-RNA (siRNA)-based libraries targeting an estrogen receptor (ER)- and aromatase-centered network, including 631 genes relevant to estrogen signaling, was designed and constructed for RNAi screening. This protocol will include the following parts: (1) selection of RNAi transfection reagent for specific cells; (2) optimization of RNAi screening conditions using Z'-factor; (3) procedure of ER-network gene siRNA library screening using automated machines under optimized experimental conditions; and (4) method of analysis for RNAi screening data to identify specific determinants important for cell proliferation. 46 genes were found to be selectively required for the survival of estrogen-independent MCF7-derived cells.
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http://dx.doi.org/10.1016/bs.mie.2019.06.002DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7533725PMC
June 2021

Defects in DNA Repair Genes Confer Improved Long-term Survival after Cisplatin-based Neoadjuvant Chemotherapy for Muscle-invasive Bladder Cancer.

Eur Urol Oncol 2020 08 10;3(4):544-547. Epub 2020 Mar 10.

Fox Chase Cancer Center, Philadelphia, PA, USA. Electronic address:

Cisplatin-based neoadjuvant chemotherapy (NAC) has demonstrated an overall survival (OS) benefit in muscle-invasive bladder cancer (MIBC). However, only a subset of patients (25-50%) have a pathologic complete response at cystectomy. Using a cohort of 58 patients from two phase 2 trials, our group previously reported that mutations in the ATM, RB1, and FANCC genes correlate with complete response to cisplatin-based NAC, and consequently improve OS and disease-specific survival (DSS). These trials enrolled patients with T2-4 (N0 or N1) MIBC and treated them with accelerated/dose-dense NAC with methotrexate, vinblastine, adriamycin, and cisplatin, or gemcitabine and cisplatin, with a plan for curative cystectomy. Updated long-term follow-up (median 74 mo) shows that significantly greater OS and DSS was maintained for patients with ATM, RB1, or FANCC mutations. The 5-yr survival rate for patients with at least one mutation was 85%, compared to 45% for patients without a mutation. On the basis of the associations with response and long-term OS and DSS, we propose that these alterations may be useful as predictive biomarkers to allow clinicians to prioritize patients who are most likely to benefit from NAC before radical cystectomy. PATIENT SUMMARY: In this report we looked at outcomes for patients with muscle-invasive bladder cancer treated with cisplatin-based chemotherapy before surgery (neoadjuvant) who had mutations in a set of DNA damage repair genes (ATM, RB1, FANCC) compared to those who did not. We found that patients who had at least one mutation in one of these genes survived longer after receiving cisplatin chemotherapy before surgery than patients who did not.
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http://dx.doi.org/10.1016/j.euo.2020.02.003DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7689684PMC
August 2020

Synthetic Lethal Targeting of Mitotic Checkpoints in HPV-Negative Head and Neck Cancer.

Cancers (Basel) 2020 Jan 28;12(2). Epub 2020 Jan 28.

Molecular Therapeutics Program, Fox Chase Cancer Center, Philadelphia, PA 19111, USA.

Head and neck squamous cell carcinomas (HNSCC) affect more than 800,000 people annually worldwide, causing over 15,000 deaths in the US. Among HNSCC cancers, human papillomavirus (HPV)-negative HNSCC has the worst outcome, motivating efforts to improve therapy for this disease. The most common mutational events in HPV-negative HNSCC are inactivation of the tumor suppressors (>85%) and (>57%), which significantly impairs G1/S checkpoints, causing reliance on other cell cycle checkpoints to repair ongoing replication damage. We evaluated a panel of cell cycle-targeting clinical agents in a group of HNSCC cell lines to identify a subset of drugs with single-agent activity in reducing cell viability. Subsequent analyses demonstrated potent combination activity between the CHK1/2 inhibitor LY2606268 (prexasertib), which eliminates a G2 checkpoint, and the WEE1 inhibitor AZD1775 (adavosertib), which promotes M-phase entry, in induction of DNA damage, mitotic catastrophe, and apoptosis, and reduction of anchorage independent growth and clonogenic capacity. These phenotypes were accompanied by more significantly reduced activation of CHK1 and its paralog CHK2, and enhanced CDK1 activation, eliminating breaks on the mitotic entry of cells with DNA damage. These data suggest the potential value of dual inhibition of CHK1 and WEE1 in tumors with compromised G1/S checkpoints.
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http://dx.doi.org/10.3390/cancers12020306DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7072436PMC
January 2020

Informatics-guided drug repurposing for Autosomal Dominant Polycystic Kidney Disease (ADPKD).

EBioMedicine 2020 02 22;52:102628. Epub 2020 Jan 22.

Molecular Therapeutics Program, Fox Chase Cancer Center, 333 Cottman Ave., Philadelphia, PA 19111, United States. Electronic address:

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http://dx.doi.org/10.1016/j.ebiom.2020.102628DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6976921PMC
February 2020

Proliferative signaling by ERBB proteins and RAF/MEK/ERK effectors in polycystic kidney disease.

Cell Signal 2020 03 9;67:109497. Epub 2019 Dec 9.

Program in Molecular Therapeutics, Fox Chase Cancer Center, 19111, USA. Electronic address:

A primary pathological feature of polycystic kidney disease (PKD) is the hyperproliferation of epithelial cells in renal tubules, resulting in formation of fluid-filled cysts. The proliferative aspects of the two major forms of PKD-autosomal dominant PKD (ADPKD), which arises from mutations in the polycystins PKD1 and PKD2, and autosomal recessive PKD (ARPKD), which arises from mutations in PKHD1-has encouraged investigation into protein components of the core cell proliferative machinery as potential drivers of PKD pathogenesis. In this review, we examine the role of signaling by ERBB proteins and their effectors, with a primary focus on ADPKD. The ERBB family of receptor tyrosine kinases (EGFR/ERBB1, HER2/ERBB2, ERBB3, and ERBB4) are activated by extracellular ligands, inducing multiple pro-growth signaling cascades; among these, activation of signaling through the RAS GTPase, and the RAF, MEK1/2, and ERK1/2 kinases enhance cell proliferation and restrict apoptosis during renal tubuloepithelial cyst formation. Characteristics of PKD include overexpression and mislocalization of the ERBB receptors and ligands, leading to enhanced activation and increased activity of downstream signaling proteins. The altered regulation of ERBBs and their effectors in PKD is influenced by enhanced activity of SRC kinase, which is promoted by the loss of cytoplasmic Ca and an increase in cAMP-dependent PKA kinase activity that stimulates CFTR, driving the secretory phenotype of ADPKD. We discuss the interplay between ERBB/SRC signaling, and polycystins and their depending signaling, with emphasis on thes changes that affect cell proliferation in cyst expansion, as well as the inflammation-associated fibrogenesis, which characterizes progressive disease. We summarize the current progress of preclinical and clinical trials directed at inhibiting this signaling axis, and discuss potential future strategies that may be productive for controlling PKD.
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http://dx.doi.org/10.1016/j.cellsig.2019.109497DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6957738PMC
March 2020

PPP2R2A prostate cancer haploinsufficiency is associated with worse prognosis and a high vulnerability to B55α/PP2A reconstitution that triggers centrosome destabilization.

Oncogenesis 2019 Dec 10;8(12):72. Epub 2019 Dec 10.

Fels Institute for Cancer Research and Molecular Biology, Temple University Lewis Katz School of Medicine, Philadelphia, PA, 19140, USA.

The PPP2R2A gene encodes the B55α regulatory subunit of PP2A. Here, we report that PPP2R2A is hemizygously lost in ~42% of prostate adenocarcinomas, correlating with reduced expression, poorer prognosis, and an increased incidence of hemizygous loss (>75%) in metastatic disease. Of note, PPP2R2A homozygous loss is less common (5%) and not increased at later tumor stages. Reduced expression of B55α is also seen in prostate tumor tissue and cell lines. Consistent with the possibility that complete loss of PPP2R2A is detrimental in prostate tumors, PPP2R2A deletion in cells with reduced but present B55α reduces cell proliferation by slowing progression through the cell cycle. Remarkably, B55α-low cells also appear addicted to lower B55α expression, as even moderate increases in B55α expression are toxic. Reconstitution of B55α expression in prostate cancer (PCa) cell lines with low B55α expression reduces proliferation, inhibits transformation and blocks xenograft tumorigenicity. Mechanistically, we show B55α reconstitution reduces phosphorylation of proteins essential for centrosomal maintenance, and induces centrosome collapse and chromosome segregation failure; a first reported link between B55α/PP2A and the vertebrate centrosome. These effects are dependent on a prolonged metaphase/anaphase checkpoint and are lethal to PCa cells addicted to low levels of B55α. Thus, we propose the reduction in B55α levels associated with hemizygous loss is necessary for centrosomal integrity in PCa cells, leading to selective lethality of B55α reconstitution. Such a vulnerability could be targeted therapeutically in the large pool of patients with hemizygous PPP2R2A deletions, using pharmacologic approaches that enhance PP2A/B55α activity.
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http://dx.doi.org/10.1038/s41389-019-0180-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6904742PMC
December 2019

Tumor-Targeted Drug Conjugates as an Emerging Novel Therapeutic Approach in Small Cell Lung Cancer (SCLC).

Cancers (Basel) 2019 Sep 3;11(9). Epub 2019 Sep 3.

Molecular Therapeutics Program, Fox Chase Cancer Center, Philadelphia, PA 19111, USA.

There are few effective therapies for small cell lung cancer (SCLC), a highly aggressive disease representing 15% of total lung cancers. With median survival <2 years, SCLC is one of the most lethal cancers. At present, chemotherapies and radiation therapy are commonly used for SCLC management. Few protein-targeted therapies have shown efficacy in improving overall survival; immune checkpoint inhibitors (ICIs) are promising agents, but many SCLC tumors do not express ICI targets such as PD-L1. This article presents an alternative approach to the treatment of SCLC: the use of drug conjugates, where a targeting moiety concentrates otherwise toxic agents in the vicinity of tumors, maximizing the differential between tumor killing and the cytotoxicity of normal tissues. Several tumor-targeted drug conjugate delivery systems exist and are currently being actively tested in the setting of SCLC. These include antibody-drug conjugates (ADCs), radioimmunoconjugates (RICs), small molecule-drug conjugates (SMDCs), and polymer-drug conjugates (PDCs). We summarize the basis of action for these targeting compounds, discussing principles of construction and providing examples of effective versus ineffective compounds, as established by preclinical and clinical testing. Such agents may offer new therapeutic options for the clinical management of this challenging disease in the future.
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http://dx.doi.org/10.3390/cancers11091297DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6769513PMC
September 2019

Comprehensive characterization of RAS mutations in colon and rectal cancers in old and young patients.

Nat Commun 2019 08 19;10(1):3722. Epub 2019 Aug 19.

Program in Molecular Therapeutics, Fox Chase Cancer Center, Philadelphia, PA, 19111, USA.

Colorectal cancer (CRC) is increasingly appreciated as a heterogeneous disease, with factors such as microsatellite instability (MSI), cancer subsite within the colon versus rectum, and age of diagnosis associated with specific disease course and therapeutic response. Activating oncogenic mutations in KRAS and NRAS are common in CRC, driving tumor progression and influencing efficacy of both cytotoxic and targeted therapies. The RAS mutational spectrum differs substantially between tumors arising from distinct tissues. Structure-function analysis of relatively common somatic RAS mutations in G12, Q61, and other codons is characterized by differing potency and modes of action. Here we show the mutational profile of KRAS, NRAS, and the less common HRAS in 13,336 CRC tumors, comparing the frequency of specific mutations based on age of diagnosis, MSI status, and colon versus rectum subsite. We identify mutation hotspots, and unexpected differences in mutation spectrum, based on these clinical parameters.
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http://dx.doi.org/10.1038/s41467-019-11530-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6700103PMC
August 2019

Combined inhibition of Aurora A and p21-activated kinase 1 as a new treatment strategy in breast cancer.

Breast Cancer Res Treat 2019 Sep 28;177(2):369-382. Epub 2019 Jun 28.

University of Colorado Denver, Young Women's Breast Cancer Translational Program, Aurora, CO, 80045, USA.

Purpose: The serine-threonine kinases Aurora A (AURKA) and p21-activated kinase 1 (PAK1) are frequently overexpressed in breast tumors, with overexpression promoting aggressive breast cancer phenotypes and poor clinical outcomes. Besides the well-defined roles of these proteins in control of cell division, proliferation, and invasion, both kinases support MAPK kinase pathway activation and can contribute to endocrine resistance by phosphorylating estrogen receptor alpha (ERα). PAK1 directly phosphorylates AURKA and its functional partners, suggesting potential value of inhibiting both kinases activity in tumors overexpressing PAK1 and/or AURKA. Here, for the first time, we evaluated the effect of combining the AURKA inhibitor alisertib and the PAK inhibitor FRAX1036 in preclinical models of breast cancer.

Methods: Combination of alisertib and FRAX1036 was evaluated in a panel of 13 human breast tumor cell lines and BT474 xenograft model, with assessment of the cell cycle by FACS, and signaling changes by immunohistochemistry and Western blot. Additionally, we performed in silico analysis to identify markers of response to alisertib and FRAX1036.

Results: Pharmacological inhibition of AURKA and PAK1 synergistically decreased survival of multiple tumor cell lines, showing particular effectiveness in luminal and HER2-enriched models, and inhibited growth and ERα-driven signaling in a BT474 xenograft model. In silico analysis suggested cell lines with dependence on AURKA are most likely to be sensitive to PAK1 inhibition.

Conclusion: Dual targeting of AURKA and PAK1 may be a promising therapeutic strategy for treatment of breast cancer, with a particular effectiveness in luminal and HER2-enriched tumor subtypes.
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http://dx.doi.org/10.1007/s10549-019-05329-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6661032PMC
September 2019

Comprehensive Genomic Landscapes in Early and Later Onset Colorectal Cancer.

Clin Cancer Res 2019 10 26;25(19):5852-5858. Epub 2019 Jun 26.

Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, Pennsylvania.

Purpose: The incidence rates of colorectal cancers are increasing in young adults. The objective of this study was to investigate genomic differences between tumor samples collected from younger and older patients with colorectal cancer.

Experimental Design: DNA was extracted from 18,218 clinical specimens, followed by hybridization capture of 3,769 exons from 403 cancer-related genes and 47 introns of 19 genes commonly rearranged in cancer. Genomic alterations (GA) were determined, and association with patient age and microsatellite stable/microsatellite instability high (MSS/MSI-H) status established.

Results: Overall genomic alteration rates in the younger (<40) and older (≥50) cohorts were similar in the majority of the genes analyzed. Gene alteration rates in the microsatellite stable (MSS) younger and older cohorts were largely similar, with several notable differences. In particular, (FDR < 0.01) and (FDR = 0.01) alterations were more common in younger patients with colorectal cancer, and (FDR < 0.01), (FDR < 0.01), (FDR < 0.01), and (FDR < 0.01) were more commonly altered in older patients with colorectal cancer. In the MSI-H cohort, the majority of genes showed similar rate of alterations in all age groups, but with significant differences seen in (FDR < 0.01), (FDR < 0.01), and KRAS (FDR < 0.01).

Conclusions: Tumors from younger and older patients with colorectal cancer demonstrated similar overall rates of genomic alteration. However, differences were noted in several genes relevant to biology and response to therapy. Further study will need to be conducted to determine whether the differences in gene alteration rates can be leveraged to provide personalized therapies for young patients with early-onset sporadic colorectal cancer.
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http://dx.doi.org/10.1158/1078-0432.CCR-19-0899DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6774873PMC
October 2019

An improved method of delivering a sclerosing agent for the treatment of malignant pleural effusion.

BMC Cancer 2019 Jun 24;19(1):614. Epub 2019 Jun 24.

Department of Cardiothoracic Surgery, Drexel University College of Medicine, Hahnemann University Hospital, 230 North Broad Street, Philadelphia, PA, 19102, USA.

Background: Malignant pleural effusion (MPE) is a devastating sequela associated with cancer. Talc pleurodesis is a common treatment strategy for MPE but has been estimated to be unsuccessful in up to 20-50% of patients. Clinical failure of talc pleurodesis is thought to be due to poor dispersion. This monograph reports the development of a foam delivery system designed to more effectively coat the pleural cavity.

Methods: C57BL/6 mice were injected with Lewis lung carcinoma (LL/2) cells intrapleurally to induce MPE. The mice then received either normal saline (NS) control, foam control (F), talc slurry (TS, 2 mg/g) or talc foam (TF, 2 mg/g). Airspace volume was evaluated by CT, lungs/pleura were collected, and percent fibrosis was determined.

Results: The TF group had significantly better survival than the TS group (21 vs 13.5 days, p < 0.0001). The average effusion volume was less in the talc groups compared to the control group (140 vs 628 μL, p < 0.001). TF induced significant lung fibrosis (p < 0.01), similar to TS. On CT, TF significantly (p < 0.05) reduced loss of right lung volume (by 30-40%) compared to the control group. This was not seen with TS (p > 0.05).

Conclusions: This report describes using a novel talc foam delivery system for the treatment of MPE. In the LL/2 model, mice treated with the TF had better survival outcomes and less reduction of lung volume than mice treated with the standard of care TS. These data provide support for translational efforts to move talc foam from animal models into clinical trials.
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http://dx.doi.org/10.1186/s12885-019-5777-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6589887PMC
June 2019

Disease-Associated Genetic Variation in Human Mitochondrial Protein Import.

Am J Hum Genet 2019 05;104(5):784-801

Cancer Prevention and Control Program, Department of Clinical Genetics, Fox Chase Cancer Center, Philadelphia, PA 19111, USA. Electronic address:

Mitochondrial dysfunction has consequences not only for cellular energy output but also for cellular signaling pathways. Mitochondrial dysfunction, often based on inherited gene variants, plays a role in devastating human conditions such as mitochondrial neuropathies, myopathies, cardiovascular disorders, and Parkinson and Alzheimer diseases. Of the proteins essential for mitochondrial function, more than 98% are encoded in the cell nucleus, translated in the cytoplasm, sorted based on the presence of encoded mitochondrial targeting sequences (MTSs), and imported to specific mitochondrial sub-compartments based on the integrated activity of a series of mitochondrial translocases, proteinases, and chaperones. This import process is typically dynamic; as cellular homeostasis is coordinated through communication between the mitochondria and the nucleus, many of the adaptive responses to stress depend on modulation of mitochondrial import. We here describe an emerging class of disease-linked gene variants that are found to impact the mitochondrial import machinery itself or to affect the proteins during their import into mitochondria. As a whole, this class of rare defects highlights the importance of correct trafficking of mitochondrial proteins in the cell and the potential implications of failed targeting on metabolism and energy production. The existence of this variant class could have importance beyond rare neuromuscular disorders, given an increasing body of evidence suggesting that aberrant mitochondrial function may impact cancer risk and therapeutic response.
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http://dx.doi.org/10.1016/j.ajhg.2019.03.019DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6506819PMC
May 2019

Unexpected Activities in Regulating Ciliation Contribute to Off-target Effects of Targeted Drugs.

Clin Cancer Res 2019 07 13;25(13):4179-4193. Epub 2019 Mar 13.

Molecular Therapeutics Program, Fox Chase Cancer Center, Philadelphia, Pennsylvania.

Purpose: For many tumors, signaling exchanges between cancer cells and other cells in their microenvironment influence overall tumor signaling. Some of these exchanges depend on expression of the primary cilium on nontransformed cell populations, as extracellular ligands including Sonic Hedgehog (SHH), PDGFRα, and others function through receptors spatially localized to cilia. Cell ciliation is regulated by proteins that are themselves therapeutic targets. We investigated whether kinase inhibitors of clinical interest influence ciliation and signaling by proteins with ciliary receptors in cancer and other cilia-relevant disorders, such as polycystic kidney disease (PKD).

Experimental Design: We screened a library of clinical and preclinical kinase inhibitors, identifying drugs that either prevented or induced ciliary disassembly. Specific bioactive protein targets of the drugs were identified by mRNA depletion. Mechanism of action was defined, and activity of select compounds investigated.

Results: We identified multiple kinase inhibitors not previously linked to control of ciliation, including sunitinib, erlotinib, and an inhibitor of the innate immune pathway kinase, IRAK4. For all compounds, activity was mediated through regulation of Aurora-A (AURKA) activity. Drugs targeting cilia influenced proximal cellular responses to SHH and PDGFRα. , sunitinib durably limited ciliation and cilia-related biological activities in renal cells, renal carcinoma cells, and PKD cysts. Extended analysis of IRAK4 defined a subset of innate immune signaling effectors potently affecting ciliation.

Conclusions: These results suggest a paradigm by which targeted drugs may have unexpected off-target effects in heterogeneous cell populations via control of a physical platform for receipt of extracellular ligands.
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http://dx.doi.org/10.1158/1078-0432.CCR-18-3535DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6606352PMC
July 2019

Microscopy-Based Automated Live Cell Screening for Small Molecules That Affect Ciliation.

Front Genet 2019 12;10:75. Epub 2019 Feb 12.

Molecular Therapeutics Program, Fox Chase Cancer Center, Philadelphia, PA, United States.

The primary monocilium, or cilium, is a single antenna-like organelle that protrudes from the surface of most mammalian cell types, and serves as a signaling hub. Mutations of cilia-associated genes result in severe genetic disorders termed ciliopathies. Among these, the most common is autosomal dominant polycystic kidney disease (ADPKD); less common genetic diseases include Bardet-Biedl syndrome, Joubert syndrome, nephronophthisis, and others. Important signaling cascades with receptor systems localized exclusively or in part at cilia include Sonic Hedgehog (SHH), platelet derived growth factor alpha (PDGFRα), WNTs, polycystins, and others. Changes in ciliation during development or in pathological conditions such as cancer impacts signaling by these proteins. Notably, ciliation status of cells is coupled closely to the cell cycle, with cilia protruding in quiescent (G0) or early G1 cells, declining in S/G2, and absent in M phase, and has been proposed to contribute to cell cycle regulation. Because of this complex biology, the elaborate machinery regulating ciliary assembly and disassembly receives input from many cellular proteins relevant to cell cycle control, development, and oncogenic transformation, making study of genetic factors and drugs influencing ciliation of high interest. One of the most effective tools to investigate the dynamics of the cilia under different conditions is the imaging of live cells. However, developing assays to observe the primary cilium in real time can be challenging, and requires a consideration of multiple details related to the cilia biology. With the dual goals of identifying small molecules that may have beneficial activity through action on human diseases, and of identifying ciliary activities of existing agents that are in common use or development, we here describe creation and evaluation of three autofluorescent cell lines derived from the immortalized retinal pigmented epithelium parental cell line hTERT-RPE1. These cell lines stably express the ciliary-targeted fluorescent proteins L13-Arl13bGFP, pEGFP-mSmo, and tdTomato-MCHR1-N-10. We then describe methods for use of these cell lines in high throughput screening of libraries of small molecule compounds to identify positive and negative regulators of ciliary disassembly.
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http://dx.doi.org/10.3389/fgene.2019.00075DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6379280PMC
February 2019

Combined Aurora Kinase A (AURKA) and WEE1 Inhibition Demonstrates Synergistic Antitumor Effect in Squamous Cell Carcinoma of the Head and Neck.

Clin Cancer Res 2019 06 12;25(11):3430-3442. Epub 2019 Feb 12.

Section of Medical Oncology, Department of Internal Medicine and Yale Cancer Center, Yale University School of Medicine, New Haven, Connecticut.

Purpose: Human papillomavirus (HPV)-negative head and neck squamous cell carcinomas (HNSCC) commonly bear disruptive mutations in , resulting in treatment resistance. In these patients, direct targeting of p53 has not been successful, but synthetic lethal approaches have promise. Although Aurora A kinase (AURKA) is overexpressed and an oncogenic driver, its inhibition has only modest clinical effects in HPV-negative HNSCC. We explored a novel combination of AURKA and WEE1 inhibition to overcome intrinsic resistance to AURKA inhibition. AURKA protein expression was determined by fluorescence-based automated quantitative analysis of patient specimens and correlated with survival. We evaluated treatment with the AURKA inhibitor alisertib (MLN8237) and the WEE1 inhibitor adavosertib (AZD1775), alone or in combination, using and HNSCC models.

Results: Elevated nuclear AURKA correlated with worse survival among patients with p16(-) HNSCC. Alisertib caused spindle defects, G-M arrest and inhibitory CDK1 phosphorylation, and cytostasis in mutant HNSCC FaDu and UNC7 cells. Addition of adavosertib to alisertib instead triggered mitotic entry and mitotic catastrophe. Moreover, in FaDu and Detroit 562 xenografts, this combination demonstrated synergistic effects on tumor growth and extended overall survival compared with either vehicle or single-agent treatment.

Conclusions: Combinatorial treatment with adavosertib and alisertib leads to synergistic antitumor effects in and HNSCC models. These findings suggest a novel rational combination, providing a promising therapeutic avenue for mutated cancers.
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http://dx.doi.org/10.1158/1078-0432.CCR-18-0440DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6548643PMC
June 2019

Interaction of germline variants in a family with a history of early-onset clear cell renal cell carcinoma.

Mol Genet Genomic Med 2019 03 24;7(3):e556. Epub 2019 Jan 24.

Cancer Prevention and Control Program, Fox Chase Cancer Center, Philadelphia, Pennsylvania.

Background: Identification of genetic factors causing predisposition to renal cell carcinoma has helped improve screening, early detection, and patient survival.

Methods: We report the characterization of a proband with renal and thyroid cancers and a family history of renal and other cancers by whole-exome sequencing (WES), coupled with WES analysis of germline DNA from additional affected and unaffected family members.

Results: This work identified multiple predicted protein-damaging variants relevant to the pattern of inherited cancer risk. Among these, the proband and an affected brother each had a heterozygous Ala45Thr variant in SDHA, a component of the succinate dehydrogenase (SDH) complex. SDH defects are associated with mitochondrial disorders and risk for various cancers; immunochemical analysis indicated loss of SDHB protein expression in the patient's tumor, compatible with SDH deficiency. Integrated analysis of public databases and structural predictions indicated that the two affected individuals also had additional variants in genes including TGFB2, TRAP1, PARP1, and EGF, each potentially relevant to cancer risk alone or in conjunction with the SDHA variant. In addition, allelic imbalances of PARP1 and TGFB2 were detected in the tumor of the proband.

Conclusion: Together, these data suggest the possibility of risk associated with interaction of two or more variants.
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http://dx.doi.org/10.1002/mgg3.556DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6418363PMC
March 2019

Molecular mechanisms of the preventable causes of cancer in the United States.

Genes Dev 2018 07 26;32(13-14):868-902. Epub 2018 Jun 26.

Koch Institute for Integrative Cancer Research, Biology Department, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.

Annually, there are 1.6 million new cases of cancer and nearly 600,000 cancer deaths in the United States alone. The public health burden associated with these numbers has motivated enormous research efforts into understanding the root causes of cancer. These efforts have led to the recognition that between 40% and 45% of cancers are associated with preventable risk factors and, importantly, have identified specific molecular mechanisms by which these exposures modify human physiology to induce or promote cancer. The increasingly refined knowledge of these mechanisms, which we summarize here, emphasizes the need for greater efforts toward primary cancer prevention through mitigation of modifiable risk factors. It also suggests exploitable avenues for improved secondary prevention (which includes the development of therapeutics designed for cancer interception and enhanced techniques for noninvasive screening and early detection) based on detailed knowledge of early neoplastic pathobiology. Such efforts would complement the current emphasis on the development of therapeutic approaches to treat established cancers and are likely to result in far greater gains in reducing morbidity and mortality.
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http://dx.doi.org/10.1101/gad.314849.118DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6075032PMC
July 2018
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