Oncology Commons^™

Efficacy Of Mcl-1 Inhibitors In Multiple Myeloma Cells Resistant To Bortezomib, Emily Nelson, Omar S. Al-Odat, Sabrina M. Paparo, Daniel A. Guirguis, Gabriella Yao, Manoj Pandey, Subash Jonnalagadda, Tulin Budak-Alpdogan

Rowan-Virtua Research Day

Multiple myeloma (MM) is a type of cancer that affects plasma B cells. Patients with MM often experience frequent relapses and can develop resistance to drugs. As a medical researcher, it is important to understand the role of Mcl-1 in preventing intrinsic apoptosis and drug resistance. Mcl-1 belongs to the anti-apoptotic subgroup of Bcl-2 family proteins and plays a crucial role in these processes. Mcl-1 plays a crucial role in driving disease progression and contributing to drug resistance in MM. It has been observed that there is an increased expression of Mcl-1 in 52% of patients with MM during diagnosis, …

Unraveling Sorafenib Resistance In Hepatocellular Carcinoma: Exploring Key Facets, Dennis Kwabiah, Kyle Doxtater, Yamile Abuchard, Sophia Leslie, Ricardo Pequeno Bracho, Shaibir Hussain, Manish K. Tripathi

Research Symposium

Hepatocellular carcinoma (HCC) stands as the prevalent form of primary liver cancer worldwide, diagnosing over half a million new cases annually. Surgical interventions like hepatectomy and liver transplantation offer a potential cure for early-stage HCC. However, the prognosis for advanced stages remains grim due to drug resistance, particularly with high refractoriness rates. Sorafenib, a tyrosine kinase inhibitor, is an approved treatment for advanced HCC. Despite its use, the overall survival extension for these patients remains limited due to the drug's ineffectiveness, and the mechanism behind advanced HCC's resistance to sorafenib remains elusive. TCGA analysis of HCC patient cohorts reveals elevated …

Lncrna Impact On Regorafenib Resistance In Colorectal Cancer, Ricardo Pequeno Bracho, Kyle Doxtater, Dennis Kwabiah, Yamile Abuchard Anaya, Sophia Leslie, Mohammad Shabir Hussain, Manish Tripathi

Research Symposium

Cancer metastasis is one of the deadliest aspects of the disease, with about 90% of all cancer-related deaths due to its development at different sites within the body. Colorectal cancer (CRC) is the second leading cause of cancer mortality in the United States, with 40-50% of all patients developing metastasis at some point during their fight with the disease. With the approval of Regorafenib for treating metastatic colorectal cancer, steps have been taken to combat metastasis in colorectal cancer. A vital aspect of the development of metastasis is the development of resistance to first-line chemotherapy. Regorafenib is an oral small-molecule …

Novel Spirocyclic Dimer, Spid3, Targets Chronic Lymphocytic Leukemia Survival Pathways With Potent Preclinical Effects, Alexandria Eiken, Audrey L. Smith, Sydney A. Skupa, Elizabeth Schmitz, Sandeep Rana, Sarbjit Singh, Siddhartha Kumar, Jayapal Reddy Mallareddy, Aguirre A. De Cubas, Akshay Krishna, Achyuth Kalluchi, M. Jordan Rowley, Christopher R. D'Angelo, Matthew A. Lunning, Gregory Bociek, Julie M. Vose, Amarnath Natarajan, Dalia El-Gamal

Journal Articles: Oncology and Hematology

Chronic lymphocytic leukemia (CLL) cell survival and growth is fueled by the induction of B-cell receptor (BCR) signaling within the tumor microenvironment (TME) driving activation of NFκB signaling and the unfolded protein response (UPR). Malignant cells have higher basal levels of UPR posing a unique therapeutic window to combat CLL cell growth using pharmacologic agents that induce accumulation of misfolded proteins. Frontline CLL therapeutics that directly target BCR signaling such as Bruton tyrosine kinase (BTK) inhibitors (e.g., ibrutinib) have enhanced patient survival. However, resistance mechanisms wherein tumor cells bypass BTK inhibition through acquired BTK mutations, and/or activation of alternative survival …

Understanding How Cancer Adapts To Stress And Therapy Using Evolutionary Game Theory, Mariyah Pressley

USF Tampa Graduate Theses and Dissertations

Adaptive responses in cancer promote disease initiation, progression, and resistance to treatment. Understanding the underlying evolutionary dynamics behind these adaptive responses is crucial for developing effective therapeutic strategies. Evolutionary game theory (EGT) has proven a useful tool in analyzing how different cellular behaviors and evolutionary forces shape the dynamics of tumor growth, response to therapy, and the emergence of resistance. In this dissertation, we utilize EGT to understand the adaptive responses of cancer through the lens of ecology and evolution. By employing fitness-generating models and exploring various ecological contexts, we aimed to unveil critical factors influencing aggressive cell phenotypes, treatment …

Blm Overexpression As A Predictive Biomarker For Chk1 Inhibitor Response In Parp Inhibitor–Resistant Brca-Mutant Ovarian Cancer, Nitasha Gupta, Tzu-Ting Huang, Jayakumar R Nair, Daniel An, Grant Zurcher, Erika J Lampert, Ann Mccoy, Ashley Cimino-Mathews, Elizabeth M Swisher, Marc R Radke, Christina M Lockwood, Jonathan B Reichel, Chih-Yuan Chiang, Kelli M Wilson, Ken Chih-Chien Cheng, Darryl Nousome, Jung-Min Lee

Journal Articles

Poly(ADP-ribose) polymerase inhibitors (PARPis) have changed the treatment paradigm in breast cancer gene (BRCA)–mutant high-grade serous ovarian carcinoma (HGSC). However, most patients eventually develop resistance to PARPis, highlighting an unmet need for improved therapeutic strategies. Using high-throughput drug screens, we identified ataxia telangiectasia and rad3-related protein/checkpoint kinase 1 (CHK1) pathway inhibitors as cytotoxic and further validated the activity of the CHK1 inhibitor (CHK1i) prexasertib in PARPi-sensitive and -resistant BRCA-mutant HGSC cells and xenograft mouse models. CHK1i monotherapy induced DNA damage, apoptosis, and tumor size reduction. We then conducted a phase 2 study (NCT02203513) of prexasertib …

Mcl-1 Inhibition Modulates Erk-Mediated Resistance In Multiple Myeloma, Omar Al-Odat, Krishne Gowda, Shantu Amin, Tulin Budak-Alpdogan, Subash Jonnalagadda, Manoj Pandey

Rowan-Virtua Research Day

Novel multiple myeloma (MM) treatments have significantly improved over the previous several decades, primarily on account of targeting bone marrow microenvironment (BMM) pathways. However, drug resistance and patient relapse remain major clinical problems. The role of BMM in the upregulation of anti-apoptotic protein Mcl-1 is well documented. The Mcl-1 protein plays a critical role in the progression and acquired drug resistance in MM. The regulation of Mcl-1, a protein characterized by a short half-life, from transcription to degradation is crucial for understanding its role in cell survival. The GSK3β and Erk play important role in the stability of Mcl-1. Also, …

Gene Expression Profiling Of Mapk Pathway Inhibitor Resistance In Cutaneous Melanoma: Can Bioinformatics Be Used To Select Better Melanoma Cell Lines?, Stephen Luebker

Theses & Dissertations

Melanoma is the deadliest form of skin cancer, and incidence has continued to increase. Half of all melanomas have a BRAF V600E mutation and respond to MAPK pathway inhibitors, including BRAF inhibitor therapy or BRAF/MEK inhibitor combination therapy, but nearly all patients develop treatment resistance. Melanoma cell lines produce variable results as models of MAPK pathway inhibitor resistance. To better understand how the genomic similarity of a melanoma cell line to patient-derived tumors affects resistance mechanisms, differences in DNA mutations and copy-number alterations were compared between melanoma cell lines profiled by the Cancer Cell Line Encyclopedia and cutaneous melanoma tumors …

Simultaneous Ck2/Tnik/Dyrk1 Inhibition By 108600 Suppresses Triple Negative Breast Cancer Stem Cells And Chemotherapy-Resistant Disease., Katsutoshi Sato, Amol A. Padgaonkar, Stacey J. Baker, Stephen C. Cosenza, Olga Rechkoblit, D.R.C. Venkata Subbaiah, Josep Domingo-Domenech, Alison Bartkowski, Elisa R. Port, Aneel K. Aggarwal, M. V. Ramana Reddy, Hanna Y. Irie, E. Premkumar Reddy

Department of Medical Oncology Faculty Papers

Triple negative breast cancer (TNBC) remains challenging because of heterogeneous responses to chemotherapy. Incomplete response is associated with a greater risk of metastatic progression. Therefore, treatments that target chemotherapy-resistant TNBC and enhance chemosensitivity would improve outcomes for these high-risk patients. Breast cancer stem cell-like cells (BCSCs) have been proposed to represent a chemotherapy-resistant subpopulation responsible for tumor initiation, progression and metastases. Targeting this population could lead to improved TNBC disease control. Here, we describe a novel multi-kinase inhibitor, 108600, that targets the TNBC BCSC population. 108600 treatment suppresses growth, colony and mammosphere forming capacity of BCSCs and induces G2M arrest …

Combating Acquired Resistance To Mapk Inhibitors In Melanoma By Targeting Abl1/2-Mediated Reactivation Of Mek/Erk/Myc Signaling., Rakshamani Tripathi, Zulong Liu, Aditi Jain,, Anastasia Lyon, Christina Meeks, Dana Richards, Jinpeng Liu, Daheng He, Chi Wang, Marika Nespi, Andrey Rymar, Peng Wang, Melissa Wilson, Rina Plattner

Department of Medical Oncology Faculty Papers

Metastatic melanoma remains an incurable disease for many patients due to the limited success of targeted and immunotherapies. BRAF and MEK inhibitors reduce metastatic burden for patients with melanomas harboring BRAF mutations; however, most eventually relapse due to acquired resistance. Here, we demonstrate that ABL1/2 kinase activities and/or expression are potentiated in cell lines and patient samples following resistance, and ABL1/2 drive BRAF and BRAF/MEK inhibitor resistance by inducing reactivation of MEK/ERK/MYC signaling. Silencing/inhibiting ABL1/2 blocks pathway reactivation, and resensitizes resistant cells to BRAF/MEK inhibitors, whereas expression of constitutively active ABL1/2 is sufficient to promote resistance. Significantly, nilotinib (2^{nd …}

Gilteritinib Or Chemotherapy For Relapsed Or Refractory Flt3-Mutated Aml, Alexander E. Perl, Giovanni Martinelli, Jorge E. Cortes, Andreas Neubauer, Ellin Berman, Stefania Paolini, Pau Montesinos, Maria R. Baer, Richard A. Larson, Celalettin Ustun, Francesco Fabbiano, Harry P. Erba, Antonio Di Stasi, Robert Stuart, Rebecca Olin, Margaret Kasner, Fabio Ciceri, Wen-Chien Chou, Nikolai Podoltsev, Christian Recher, Hisayuki Yokoyama, Naoko Hosono, Sung-Soo Yoon, Je-Hwan Lee, Timothy Pardee, Amir T. Fathi, Chaofeng Liu, Nahla Hasabou, Xuan Liu, Erkut Bahceci, Mark J. Levis

Department of Medical Oncology Faculty Papers

BACKGROUND: Patients with relapsed or refractory acute myeloid leukemia (AML) with mutations in the FMS-like tyrosine kinase 3 gene (FLT3) infrequently have a response to salvage chemotherapy. Gilteritinib is an oral, potent, selective FLT3 inhibitor with single-agent activity in relapsed or refractory FLT3-mutated AML.

METHODS: In a phase 3 trial, we randomly assigned adults with relapsed or refractory FLT3-mutated AML in a 2:1 ratio to receive either gilteritinib (at a dose of 120 mg per day) or salvage chemotherapy. The two primary end points were overall survival and the percentage of patients who had complete remission …

Intravesical Rad-Ifnα/Syn3 For Patients With High-Grade, Bacillus Calmette-Guerin-Refractory Or Relapsed Non-Muscle-Invasive Bladder Cancer: A Phase Ii Randomized Study., Neal D Shore, Stephen A Boorjian, Daniel J Canter, Kenneth Ogan, Lawrence I Karsh, Tracy M Downs, Leonard G Gomella, Ashish M Kamat, Yair Lotan, Robert S Svatek, Trinity J Bivalacqua, Robert L Grubb, Tracey L Krupski, Seth P Lerner, Michael E Woods, Brant A Inman, Matthew I Milowsky, Alan Boyd, F Peter Treasure, Gillian Gregory, David G Sawutz, Seppo Yla-Herttuala, Nigel R Parker, Colin P N Dinney

Department of Medicine Faculty Papers

Purpose Many patients with high-risk non-muscle-invasive bladder cancer (NMIBC) are either refractory to bacillus Calmette-Guerin (BCG) treatment or may experience disease relapse. We assessed the efficacy and safety of recombinant adenovirus interferon alfa with Syn3 (rAd-IFNα/Syn3), a replication-deficient recombinant adenovirus gene transfer vector, for patients with high-grade (HG) BCG-refractory or relapsed NMIBC. Methods In this open-label, multicenter (n = 13), parallel-arm, phase II study ( ClinicalTrials.gov identifier: NCT01687244), 43 patients with HG BCG-refractory or relapsed NMIBC received intravesical rAd-IFNα/Syn3 (randomly assigned 1:1 to 1 × 10(11) viral particles (vp)/mL or 3 × 10(11) vp/mL). Patients who responded at months 3, …

Ibrutinib Unmasks Critical Role Of Bruton Tyrosine Kinase In Primary Cns Lymphoma., Christian Grommes, Alessandro Pastore, Nicolaos Palaskas, Sarah S. Tang, Carl Campos, Derrek Schartz, Paolo Codega, Donna Nichol, Owen Clark, Wan-Ying Hsieh, Dan Rohle, Marc Rosenblum, Agnes Viale, Viviane S. Tabar, Cameron W. Brennan, Igor T. Gavrilovic, Thomas J. Kaley, Craig P. Nolan, Antonio Omuro, Elena Pentsova, Alissa A. Thomas, Elina Tsyvkin, Ariela Noy, M. Lia Palomba, Paul Hamlin, Craig S. Sauter, Craig H. Moskowitz, Julia Wolfe, Ahmet Dogan, Minhee Won, Jon Glass, Scott Peak, Enrico C. Lallana, Vaios Hatzoglou, Anne S. Reiner, Philip H. Gutin, Jason T. Huse, Katherine S. Panageas, Thomas G. Graeber, Nikolaus Schultz, Lisa M. Deangelis, Ingo K. Mellinghoff

Department of Neurology Faculty Papers

Bruton tyrosine kinase (BTK) links the B-cell antigen receptor (BCR) and Toll-like receptors with NF-κB. The role of BTK in primary central nervous system (CNS) lymphoma (PCNSL) is unknown. We performed a phase I clinical trial with ibrutinib, the first-in-class BTK inhibitor, for patients with relapsed or refractory CNS lymphoma. Clinical responses to ibrutinib occurred in 10 of 13 (77%) patients with PCNSL, including five complete responses. The only PCNSL with complete ibrutinib resistance harbored a mutation within the coiled-coil domain of CARD11, a known ibrutinib resistance mechanism. Incomplete tumor responses were associated with mutations in the B-cell antigen receptor-associated …

Posttranscriptional Upregulation Of Idh1 By Hur Establishes A Powerful Survival Phenotype In Pancreatic Cancer Cells., Mahsa Zarei, Shruti Lal, Seth J. Parker, Avinoam Nevler, Ali Vaziri-Gohar, Katerina Dukleska, Nicole C. Mambelli-Lisboa, Cynthia Moffat, Fernando F Blanco, Saswati N. Chand, Masaya Jimbo, Joseph A. Cozzitorto, Wei Jiang, Charles J. Yeo, Eric R. Londin, Erin L. Seifert, Christian M. Metallo, Jonathan R. Brody, Jordan M. Winter

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Cancer aggressiveness may result from the selective pressure of a harsh nutrient-deprived microenvironment. Here we illustrate how such conditions promote chemotherapy resistance in pancreatic ductal adenocarcinoma (PDAC). Glucose or glutamine withdrawal resulted in a 5- to 10-fold protective effect with chemotherapy treatment. PDAC xenografts were less sensitive to gemcitabine in hypoglycemic mice compared with hyperglycemic mice. Consistent with this observation, patients receiving adjuvant gemcitabine (n = 107) with elevated serum glucose levels (HgbA1C > 6.5%) exhibited improved survival. We identified enhanced antioxidant defense as a driver of chemoresistance in this setting. ROS levels were doubled in vitro by either nutrient withdrawal …

Inhibition Of Age-Related Therapy Resistance In Melanoma By Rosiglitazone-Mediated Induction Of Klotho., Reeti Behera, Amanpreet Kaur, Marie R. Webster, Suyeon Kim, Abibatou Ndoye, Curtis H. Kugel, Gretchen M. Alicea, Joshua Wang, Kanad Ghosh, Phil Cheng, Sofia Lisanti, Katie Marchbank, Vanessa Dang, Mitchell Levesque, Reinhard Dummer, Xiaowei Xu, Meenhard Herlyn, Andrew E. Aplin, Alexander Roesch, Cecilia Caino, Dario C. Altieri, Ashani T. Weeraratna

Department of Cancer Biology Faculty Papers

Purpose: Aging is a poor prognostic factor for melanoma. We have shown that melanoma cells in an aged microenvironment are more resistant to targeted therapy than identical cells in a young microenvironment. This is dependent on age-related secreted factors. Klotho is an age-related protein whose serum levels decrease dramatically by age 40. Most studies on klotho in cancer have focused on the expression of klotho in the tumor cell. We have shown that exogenous klotho inhibits internalization and signaling of Wnt5A, which drives melanoma metastasis and resistance to targeted therapy. We investigate here whether increasing klotho in the aged microenvironment …

Co-Targeting Hgf/Cmet Signaling With Mek Inhibitors In Metastatic Uveal Melanoma., Hanyin Cheng, Vivian Chua, Connie Liao, Timothy J. Purwin, Mizue Terai, Ken Kageyama, Michael A. Davies, Takami Sato, Andrew E. Aplin

Department of Cancer Biology Faculty Papers

Patients with metastatic uveal melanoma usually die within 1 year of diagnosis, emphasizing an urgent need to develop new treatment strategies. The liver is the most common site of metastasis. Mitogen-activated protein kinase kinase (MEK) inhibitors improve survival in V600 BRAF-mutated cutaneous melanoma patients but have limited efficacy in patients with uveal melanoma. Our previous work showed that hepatocyte growth factor (HGF) signaling elicits resistance to MEK inhibitors in metastatic uveal melanoma. In this study, we demonstrate that expression of two BH3-only family proteins, Bim-EL and Bmf, contributes to HGF-mediated resistance to MEK inhibitors. Targeting HGF/cMET signaling with LY2875358, a …

Structure-Based Screen Identifies A Potent Small Molecule Inhibitor Of Stat5a/B With Therapeutic Potential For Prostate Cancer And Chronic Myeloid Leukemia., Zhiyong Liao, Lei Gu, Jenny Vergalli, Samanta A. Mariani, Marco De Dominici, Ravi K. Lokareddy, Ayush Dagvadorj, Puranik Purushottamachar, Peter A. Mccue, Edouard J. Trabulsi, Costas D. Lallas, Shilpa Gupta, Elyse Ellsworth, Shauna Blackmon, Adam Ertel, Paolo Fortina, Benjamin E. Leiby, Guanjun Xia, Hallgeir Rui, David T. Hoang, Leonard G Gomella, Gino Cingolani, Vincent Njar, Nagarajan Pattabiraman, Bruno Calabretta, Marja T. Nevalainen

Department of Cancer Biology Faculty Papers

Bypassing tyrosine kinases responsible for Stat5a/b phosphorylation would be advantageous for therapy development for Stat5a/b-regulated cancers. Here, we sought to identify small molecule inhibitors of Stat5a/b for lead optimization and therapy development for prostate cancer and Bcr-Abl-driven leukemias. In silico screening of chemical structure databases combined with medicinal chemistry was used for identification of a panel of small molecule inhibitors to block SH2 domain-mediated docking of Stat5a/b to the receptor-kinase complex and subsequent phosphorylation and dimerization. We tested the efficacy of the lead compound IST5-002 in experimental models and patient samples of two known Stat5a/b-driven cancers, prostate cancer and chronic …

Paracrine Effect Of Nrg1 And Hgf Drives Resistance To Mek Inhibitors In Metastatic Uveal Melanoma., Hanyin Cheng, Mizue Terai, Ken Kageyama, Shinji Ozaki, Peter Mccue, Takami Sato, Andrew E. Aplin

Department of Cancer Biology Faculty Papers

Uveal melanoma patients with metastatic disease usually die within one year, emphasizing an urgent need to develop new treatment strategies for this cancer. MEK inhibitors improve survival in cutaneous melanoma patients but show only modest efficacy in metastatic uveal melanoma patients. In this study, we screened for growth factors that elicited resistance in newly characterized metastatic uveal melanoma cell lines to clinical-grade MEK inhibitors, trametinib and selumetinib. We show that neuregulin 1 (NRG1) and hepatocyte growth factor (HGF) provide resistance to MEK inhibition. Mechanistically, trametinib enhances the responsiveness to NRG1 and sustained HGF-mediated activation of AKT. Individually targeting ERBB3 and …

Exploiting High-Throughput Cell Line Drug Screening Studies To Identify Candidate Therapeutic Agents In Head And Neck Cancer, Anthony C Nichols, Morgan Black, John Yoo, Nicole Pinto, Andrew Fernandes, Benjamin Haibe-Kains, Paul C Boutros, John W Barrett

Oncology Publications

BACKGROUND: There is an urgent need for better therapeutics in head and neck squamous cell cancer (HNSCC) to improve survival and decrease treatment morbidity. Recent advances in high-throughput drug screening techniques and next-generation sequencing have identified new therapeutic targets in other cancer types, but an HNSCC-specific study has not yet been carried out. We have exploited data from two large-scale cell line projects to clearly describe the mutational and copy number status of HNSCC cell lines and identify candidate drugs with elevated efficacy in HNSCC.

METHODS: The genetic landscape of 42 HNSCC cell lines including mutational and copy number data …

A Statement On Vemurafenib-Resistant Melanoma., Edward J Hartsough, A E Aplin

Department of Cancer Biology Faculty Papers

Despite recent advancements in the treatment of late-stage mutant BRAF (V600E/K) melanomas, a major hurdle continues to be acquired resistance to BRAF inhibitors such as vemurafenib. The mechanisms for resistance have proven to be heterogeneous, emphasizing the need to use broad therapeutic approaches. In this issue, the study "Stat3-targeted therapies overcome the acquired resistance to vemurafenib in melanomas" by Liu et al. proposes that signal transducer and activator of transcription 3 (STAT3)-paired box 3 (PAX3) signaling may be a mechanism that is used by melanomas to resist RAF inhibitors.

Gene Expression Signatures Modulated By Epidermal Growth Factor Receptor Activation And Their Relationship To Cetuximab Resistance In Head And Neck Squamous Cell Carcinoma., Elana J Fertig, Qing Ren, Haixia Cheng, Hiromitsu Hatakeyama, Adam Dicker Md, Phd, Ulrich Rodeck, Michael Considine, Michael F Ochs, Christine H Chung

Department of Radiation Oncology Faculty Papers

BACKGROUND: Aberrant activation of signaling pathways downstream of epidermal growth factor receptor (EGFR) has been hypothesized to be one of the mechanisms of cetuximab (a monoclonal antibody against EGFR) resistance in head and neck squamous cell carcinoma (HNSCC). To infer relevant and specific pathway activation downstream of EGFR from gene expression in HNSCC, we generated gene expression signatures using immortalized keratinocytes (HaCaT) subjected to ligand stimulation and transfected with EGFR, RELA/p65, or HRASVal12D.

RESULTS: The gene expression patterns that distinguished the HaCaT variants and conditions were inferred using the Markov chain Monte Carlo (MCMC) matrix factorization algorithm Coordinated Gene Activity …

Mechanisms Of Resistance To Raf Inhibitors In Melanoma., A E Aplin, Fred M Kaplan, Yongping Shao

Department of Cancer Biology Faculty Papers

The recent RAF inhibitor trial with PLX4032/RG7204 in late-stage mutant B-RAF melanoma patients has been lauded as a success story for personalized cancer therapy since short-term clinical responses were observed in the majority of patients. However, initial responses were followed by subsequent tumor re-growth, and a subset of patients showed intrinsic resistance. Bi-directional translational efforts are now essential to determine the mechanisms underlying acquired/secondary and intrinsic resistance to RAF inhibitors.

Pp32 (Anp32a) Expression Inhibits Pancreatic Cancer Cell Growth And Induces Gemcitabine Resistance By Disrupting Hur Binding To Mrnas., Timothy K Williams, Christina L Costantino, Nikolai A Bildzukewicz, Nathan G Richards, David W Rittenhouse, Lisa Einstein, Joseph A Cozzitorto, Judith C Keen, Abhijit Dasgupta, Myriam Gorospe, Gregory E Gonye, Charles J Yeo, Agnieszka K Witkiewicz, Jonathan R Brody

Department of Surgery Faculty Papers

The expression of protein phosphatase 32 (PP32, ANP32A) is low in poorly differentiated pancreatic cancers and is linked to the levels of HuR (ELAV1), a predictive marker for gemcitabine response. In pancreatic cancer cells, exogenous overexpression of pp32 inhibited cell growth, supporting its long-recognized role as a tumor suppressor in pancreatic cancer. In chemotherapeutic sensitivity screening assays, cells overexpressing pp32 were selectively resistant to the nucleoside analogs gemcitabine and cytarabine (ARA-C), but were sensitized to 5-fluorouracil; conversely, silencing pp32 in pancreatic cancer cells enhanced gemcitabine sensitivity. The cytoplasmic levels of pp32 increased after cancer cells are treated with certain stressors, …

Oncolog Volume 53, Number 10, October 2008, Joe Munch, Sunita Patterson

OncoLog MD Anderson's Report to Physicians (All issues)

• Pancreatic Cancer: The Prognosis Is Changing
• Delivering “The Guardian of the Genome”
• House Call: “Seeing” Cancer from the Outside
• Catching Pancreatic Cancer Early

Colon Carcinoma Cells Harboring Pik3ca Mutations Display Resistance To Growth Factor Deprivation Induced Apoptosis., J. Wang, Karen Kuropatwinski, Jennie Hauser, Michael R. Rossi, Yunfei Zhou, Alexis Conway, Julie L.C. Kan, Neil W. Gibson, James K.V. Willson, John K. Cowell, Michael G. Brattain

Journal Articles: Eppley Institute

PIK3CA, encoding the p110alpha catalytic subunit of phosphatidylinositol 3-kinase (PI3K), is mutated in a variety of human cancers. We screened the colon cancer cell lines previously established in our laboratory for PIK3CA mutations and found that four of them harbored gain of function mutations. We have now compared a panel of mutant and wild-type cell lines for cell proliferation and survival in response to stress. There was little difference in PI3K activity between mutant PIK3CA-bearing cells (mutant cells) and wild-type PIK3CA-bearing cells (wild-type cells) under optimal growth conditions. However, the mutant cells showed constitutive PI3K activity during growth factor deprivation …