Genetic Phenomena Commons^™

Tsyn-Seq: A T-Cell Synapse-Based Antigen Identification Platform, Yimei Jin, Takahiko Miyama, Alexandria Brown, Tomo Hayase, Xingzhi Song, Anand K Singh, Licai Huang, Ivonne I Flores, Lauren K Mcdaniel, Israel Glover, Taylor M Halsey, Rishika Prasad, Valerie Chapa, Saira Ahmed, Jianhua Zhang, Kunal Rai, Christine B Peterson, Gregory Lizee, Jennifer Karmouch, Eiko Hayase, Jeffrey J Molldrem, Chia-Chi Chang, Wen-Bin Tsai, Robert R Jenq

Faculty, Staff and Student Publications

Tools for genome-wide rapid identification of peptide-major histocompatibility complex targets of T-cell receptors (TCR) are not yet universally available. We present a new antigen screening method, the T-synapse (Tsyn) reporter system, which includes antigen-presenting cells (APC) with a Fas-inducible NF-κB reporter and T cells with a nuclear factor of activated T cells (NFAT) reporter. To functionally screen for target antigens from a cDNA library, productively interacting T cell-APC aggregates were detected by dual-reporter activity and enriched by flow sorting followed by antigen identification quantified by deep sequencing (Tsyn-seq). When applied to a previously characterized TCR specific for the E7 antigen …

Fam86a Methylation Of Eef2 Links Mrna Translation Elongation To Tumorigenesis, Joel William Francis, Simone Hausmann, Sabeen Ikram, Kunlun Yin, Robert Mealey-Farr, Natasha Mahealani Flores, Annie Truc Trinh, Tourkian Chasan, Julia Thompson, Pawel Karol Mazur, Or Gozani

Faculty, Staff and Student Publications

eEF2 post-translational modifications (PTMs) can profoundly affect mRNA translation dynamics. However, the physiologic function of eEF2K525 trimethylation (eEF2K525me3), a PTM catalyzed by the enzyme FAM86A, is unknown. Here, we find that FAM86A methylation of eEF2 regulates nascent elongation to promote protein synthesis and lung adenocarcinoma (LUAD) pathogenesis. The principal physiologic substrate of FAM86A is eEF2, with K525me3 modeled to facilitate productive eEF2-ribosome engagement during translocation. FAM86A depletion in LUAD cells causes 80S monosome accumulation and mRNA translation inhibition. FAM86A is overexpressed in LUAD and eEF2K525me3 levels increase through advancing LUAD disease stages. FAM86A knockdown attenuates LUAD cell proliferation and suppression …

A Novel Sik2 Inhibitor Sic-19 Exhibits Synthetic Lethality With Parp Inhibitors In Ovarian Cancer, Fang Wang, Xuejiao Yu, Jun Qian, Yumin Cao, Shunli Dong, Shenghua Zhan, Zhen Lu, Robert C Bast, Qingxia Song, Youguo Chen, Yi Zhang, Jinhua Zhou

Faculty, Staff and Student Publications

Purpose: Ovarian cancer patients with HR proficiency (HRP) have had limited benefits from PARP inhibitor treatment, highlighting the need for improved therapeutic strategies. In this study, we developed a novel SIK2 inhibitor, SIC-19, and investigated its potential to enhance the sensitivity and expand the clinical utility of PARP inhibitors in ovarian cancer.

Methods: The SIK2 protein was modeled using a Molecular Operating Environment (MOE), and the most favorable model was selected based on a GBVI/WSA dG scoring function. The Chembridge Compound Library was screened, and the top 20 candidate compounds were tested for their interaction with SIK2 and downstream substrates, …

The Prognostic Value Of Mek Pathway-Associated Estrogen Receptor Signaling Activity For Female Cancers, Chun Wai Ng, Yvonne T M Tsang, David M Gershenson, Kwong-Kwok Wong

Faculty, Staff and Student Publications

Background: Other than for breast cancer, endocrine therapy has not been highly effective for gynecologic cancers. Endocrine therapy resistance in estrogen receptor positive gynecologic cancers is still poorly understood. In this retrospective study, we examined the estrogen receptor (ER) signaling pathway activities of breast, ovarian, endometrial, and cervical cancers to identify those that may predict endocrine therapy responsiveness.

Methods: Clinical and genomic data of women with breast and gynecological cancers were downloaded from cBioPortal for Cancer Genomics. Estrogen receptor alpha (ESR1) expression level and sample-level pathway enrichment scores (EERES) were calculated to classify patients into four groups (low/high ESR1 and …

Evolution Of Chromosome-Arm Aberrations In Breast Cancer Through Genetic Network Rewiring, Elena Kuzmin, Toby M Baker, Tom Lesluyes, Jean Monlong, Kento T Abe, Paula P Coelho, Michael Schwartz, Joseph Del Corpo, Dongmei Zou, Genevieve Morin, Alain Pacis, Yang Yang, Constanza Martinez, Jarrett Barber, Hellen Kuasne, Rui Li, Mathieu Bourgey, Anne-Marie Fortier, Peter G Davison, Atilla Omeroglu, Marie-Christine Guiot, Quaid Morris, Claudia L Kleinman, Sidong Huang, Anne-Claude Gingras, Jiannis Ragoussis, Guillaume Bourque, Peter Van Loo, Morag Park

Faculty, Staff and Student Publications

The basal breast cancer subtype is enriched for triple-negative breast cancer (TNBC) and displays consistent large chromosomal deletions. Here, we characterize evolution and maintenance of chromosome 4p (chr4p) loss in basal breast cancer. Analysis of The Cancer Genome Atlas data shows recurrent deletion of chr4p in basal breast cancer. Phylogenetic analysis of a panel of 23 primary tumor/patient-derived xenograft basal breast cancers reveals early evolution of chr4p deletion. Mechanistically we show that chr4p loss is associated with enhanced proliferation. Gene function studies identify an unknown gene, C4orf19, within chr4p, which suppresses proliferation when overexpressed-a member of the PDCD10-GCKIII kinase module …

Cpsf3 Inhibition Blocks Pancreatic Cancer Cell Proliferation Through Disruption Of Core Histone Mrna Processing, Abdulrahman A Alahmari, Aditi H Chaubey, Venkata S Jonnakuti, Arwen A Tisdale, Carla D Schwarz, Abigail C Cornwell, Kathryn E Maraszek, Emily J Paterson, Minsuh Kim, Swati Venkat, Eduardo Cortes Gomez, Jianmin Wang, Katerina V Gurova, Hari Krishna Yalamanchili, Michael E Feigin

Duncan NRI Faculty and Staff Publications

Pancreatic ductal adenocarcinoma (PDAC) is a lethal disease with limited effective treatment options, potentiating the importance of uncovering novel drug targets. Here, we target cleavage and polyadenylation specificity factor 3 (CPSF3), the 3′ endonuclease that catalyzes mRNA cleavage during polyadenylation and histone mRNA processing. We find that CPSF3 is highly expressed in PDAC and is associated with poor prognosis. CPSF3 knockdown blocks PDAC cell proliferation and colony formation in vitro and tumor growth in vivo. Chemical inhibition of CPSF3 by the small molecule JTE-607 also attenuates PDAC cell proliferation and colony formation, while it has no effect on cell proliferation …

Tumor-Specific Polycistronic Mirna Delivered By Engineered Exosomes For The Treatment Of Glioblastoma, Malcolm F Mcdonald, Anwar Hossain, Eric N Momin, Irtiza Hasan, Sanjay Singh, Satoshi Adachi, Joy Gumin, Daniel Ledbetter, Jing Yang, Lihong Long, Marc Daou, Sricharan Gopakumar, Lynette M Phillips, Brittany Parker Kerrigan, Frederick F Lang

Faculty, Staff and Student Publications

Background: Glioblastoma (GBM) has poor prognosis due to ineffective agents and poor delivery methods. MicroRNAs (miRs) have been explored as novel therapeutics for GBM, but the optimal miRs and the ideal delivery strategy remain unresolved. In this study, we sought to identify the most effective pan-subtype anti-GBM miRs and to develop an improved delivery system for these miRs.

Methods: We conducted an unbiased screen of over 600 miRs against 7 glioma stem cell (GSC) lines representing all GBM subtypes to identify a set of pan-subtype-specific anti-GBM miRs and then used available TCGA GBM patient outcomes and miR expression data to …

Induced Degradation Of Lineage-Specific Oncoproteins Drives The Therapeutic Vulnerability Of Small Cell Lung Cancer To Parp Inhibitors, Chiho Kim, Xu-Dong Wang, Zhengshuai Liu, Jianwei Hao, Shuai Wang, Peng Li, Zhenzhen Zi, Qing Ding, Seoyeon Jang, Jiwoong Kim, Yikai Luo, Kenneth E Huffman, Shreoshi Pal Choudhuri, Sofia Del Rio, Ling Cai, Han Liang, Benjamin J Drapkin, John D Minna, Yonghao Yu

Faculty, Staff and Student Publications

Although BRCA1/2 mutations are not commonly found in small cell lung cancer (SCLC), a substantial fraction of SCLC shows clinically relevant response to PARP inhibitors (PARPis). However, the underlying mechanism(s) of PARPi sensitivity in SCLC is poorly understood. We performed quantitative proteomic analyses and identified proteomic changes that signify PARPi responses in SCLC cells. We found that the vulnerability of SCLC to PARPi could be explained by the degradation of lineage-specific oncoproteins (e.g., ASCL1). PARPi-induced activation of the E3 ligase HUWE1 mediated the ubiquitin-proteasome system (UPS)-dependent ASCL1 degradation. Although PARPi induced a general DNA damage response in SCLC cells, this …

Mir126-Targeted-Nanoparticles Combined With Pi3k/Akt Inhibitor As A New Strategy To Overcome Melanoma Resistance, Maria Beatrice Arasi, Gabriele De Luca, Laura Chronopoulou, Francesca Pedini, Eleonora Petrucci, Michela Flego, Annarita Stringaro, Marisa Colone, Luca Pasquini, Massimo Spada, Valentina Lulli, Maria Chiara Perrotta, George Adrian Calin, Cleofe Palocci, Mauro Biffoni, Federica Felicetti, Nadia Felli

Faculty, Staff and Student Publications

Metastatic melanoma poses significant challenges as a highly lethal disease. Despite the success of molecular targeting using BRAFV600E inhibitors (BRAFis) and immunotherapy, the emergence of early recurrence remains an issue and there is the need for novel therapeutic approaches. This study aimed at creating a targeted delivery system for the oncosuppressor microRNA 126 (miR126) and testing its effectiveness in combination with a phosphatidylinositol 3-kinase (PI3K)/ protein kinase B (AKT) inhibitor for treating metastatic melanoma resistant to BRAFis. To achieve this, we synthesized chitosan nanoparticles containing a chemically modified miR126 sequence. These nanoparticles were further functionalized with an antibody specific to …

Single-Cell Rna Sequencing Analysis Identifies Acute Changes In The Tumor Microenvironment Induced By Interferon Α Gene Therapy In A Murine Bladder Cancer Model, Alexis R Steinmetz, Morgan Pierce, Alberto Martini, Come Tholomier, Ganiraju Manyam, Yan Chen, Akshay Sood, Jonathan J Duplisea, Burles A Johnson, Bogdan A Czerniak, Byron H Lee, Chinnaswamy Jagannath, Seppo Yla-Herttuala, Nigel R Parker, David J Mcconkey, Colin P Dinney, Sharada Mokkapati

Faculty, Staff and Student Publications

Introduction: Nadofaragene firadenovec (Ad-IFNα/Syn3) is now approved for BCG-unresponsive bladder cancer (BLCA). IFNα is a pleiotropic cytokine that causes direct tumor cell killing via TRAIL-mediated apoptosis, angiogenesis inhibition, and activation of the innate and adaptive immune system. We established an immunocompetent murine BLCA model to study the effects of murine adenoviral IFNα (muAd-Ifnα) gene therapy on cancer cells and the tumor microenvironment using a novel murine equivalent of Nadofaragene firadenovec (muAd-Ifnα).

Methods: Tumors were induced by instilling MB49 cells into the bladders of mice; luciferase imaging confirmed tumor development. Mice were treated with adenovirus control (Ad-Ctrl; empty vector), or muAd-Ifnα …

From Mitochondria To Tumor Suppression: Acat1’S Crucial Role In Gastric Cancer, Wei He, Yanfang Li, Song-Bai Liu, Ying Chang, Shiyuan Han, Xingyu Han, Zixin Ma, Hesham M Amin, Yao-Hua Song, Jin Zhou

Faculty, Staff and Student Publications

Acetyl CoA acetyltransferase 1 (ACAT1), a mitochondrial enzyme, is mainly involved in the formation and decomposition of ketones, isoleucine, and fatty acids. Previous clinical studies showed that mutations in the ACAT1 gene lead to ketoacidosis, Notably the role of ACAT1 in human cancer' pathogenesis varies depending on cancer type, and its specific role in gastric cancer remains largely unknown. In the current study, we found that the expression of ACAT1 in primary late-stage gastric cancer tumor tissues was significantly lower than in early-stage tumors. This observation was further confirmed in high-grade gastric cancer cell line MKN45. The expression of CD44 …

Inhibition Of Src-3 As A Potential Therapeutic Strategy For Aggressive Mantle Cell Lymphoma, Imani Bijou, Yang Liu, Dong Lu, Jianwei Chen, Shelby Sloan, Lapo Alinari, David M Lonard, Bert W O'Malley, Michael Wang, Jin Wang

Faculty, Staff and Students Publications

Mantle cell lymphoma (MCL) has a poor prognosis and high relapse rates despite current therapies, necessitating novel treatment regimens. Inhibition of SRC-3 show effectiveness in vivo and in vitro in other B cell lymphomas. Additionally, previous studies have shown that SRC-3 is highly expressed in the lymph nodes of B cell non-Hodgkin's lymphoma patients, suggesting SRC-3 may play a role in the progression of B cell lymphoma. This study aimed to investigate novel SRC-3 inhibitors, SI-10 and SI-12, in mantle cell lymphoma. The cytotoxic effects of SI-10 and SI-12 were evaluated in vitro and demonstrated dose-dependent cytotoxicity in a panel …

Competing Engagement Of Β-Arrestin Isoforms Balances Igf1r/P53 Signaling And Controls Melanoma Cell Chemotherapeutic Responsiveness, Sonia Cismas, Sylvya Pasca, Caitrin Crudden, Iara Trocoli Drakensjo, Naida Suleymanova, Simin Zhang, Benjamin Gebhard, Dawei Song, Shiyong Neo, Takashi Shibano, Terry J Smith, George A Calin, Ada Girnita, Leonard Girnita

Faculty, Staff and Student Publications

Constraints on the p53 tumor suppressor pathway have long been associated with the progression, therapeutic resistance, and poor prognosis of melanoma, the most aggressive form of skin cancer. Likewise, the insulin-like growth factor type 1 receptor (IGF1R) is recognized as an essential coordinator of transformation, proliferation, survival, and migration of melanoma cells. Given that β-arrestin (β-arr) system critically governs the anti/pro-tumorigenic p53/IGF1R signaling pathways through their common E3 ubiquitin-protein ligase MDM2, we explore whether unbalancing this system downstream of IGF1R can enhance the response of melanoma cells to chemotherapy. Altering β-arr expression demonstrated that both β-arr1-silencing and β-arr2-overexpression (-β-arr1/+β-arr2) facilitated …

Kinome Profiling Identifies Mark3 And Stk10 As Potential Therapeutic Targets In Uveal Melanoma, Usman Baqai, Alison M Kurimchak, Isabella V Trachtenberg, Timothy J Purwin, Jelan I Haj, Anna Han, Kristine Luo, Nikole Fandino Pachon, Angela Jeon, Vivian Chua, Michael A Davies, J Silvio Gutkind, Jeffrey L Benovic, James S Duncan, Andrew E Aplin

Faculty, Staff and Student Publications

Most uveal melanoma cases harbor activating mutations in either GNAQ or GNA11. Despite activation of the mitogen-activated protein kinase (MAPK) signaling pathway downstream of Gαq/11, there are no effective targeted kinase therapies for metastatic uveal melanoma. The human genome encodes numerous understudied kinases, also called the "dark kinome". Identifying additional kinases regulated by Gαq/11 may uncover novel therapeutic targets for uveal melanoma. In this study, we treated GNAQ-mutant uveal melanoma cell lines with a Gαq/11 inhibitor, YM-254890, and conducted a kinase signaling proteomic screen using multiplexed-kinase inhibitors followed by mass spectrometry. We observed downregulated expression and/or activity of 22 kinases. …

Potentiation Of Apoptosis In Drug-Resistant Mantle Cell Lymphoma Cells By Mcl-1 Inhibitor Involves Downregulation Of Inhibitor Of Apoptosis Proteins, Yijing Li, Heng-Huan Lee, Vivian Changying Jiang, Yuxuan Che, Joseph Mcintosh, Alexa Jordan, Jovanny Vargas, Tianci Zhang, Fangfang Yan, Margaret Elizabeth Simmons, Wei Wang, Lei Nie, Yixin Yao, Preetesh Jain, Michael Wang, Yang Liu

Faculty, Staff and Student Publications

Bruton's tyrosine kinase inhibitors (BTKi) and CAR T-cell therapy have demonstrated tremendous clinical benefits in mantle cell lymphoma (MCL) patients, but intrinsic or acquired resistance inevitably develops. In this study, we assessed the efficacy of the highly potent and selective MCL-1 inhibitor AZD5991 in various therapy-resistant MCL cell models. AZD5991 markedly induced apoptosis in these cells. In addition to liberating BAK from the antiapoptotic MCL-1/BAK complex for the subsequent apoptosis cascade, AZD5991 downregulated inhibitor of apoptosis proteins (IAPs) through a BAK-dependent mechanism to amplify the apoptotic signal. The combination of AZD5991 with venetoclax enhanced apoptosis and reduced mitochondrial oxygen consumption …

Exosomes Modified With Anti-Mek1 Sirna Lead To An Effective Silencing Of Triple Negative Breast Cancer Cells, Débora Ferreira, Cátia Santos-Pereira, Marta Costa, Julieta Afonso, Sujuan Yang, Janine Hensel, Kathleen M Mcandrews, Adhemar Longatto-Filho, Rui Fernandes, Joana B Melo, Fátima Baltazar, João N Moreira, Raghu Kalluri, Ligia R Rodrigues

Faculty, Staff and Student Publications

Triple negative breast cancer (TNBC) is a highly heterogenous disease not sensitive to endocrine or HER2 therapy and standardized treatment regimens are still missing. Therefore, development of novel TNBC treatment approaches is of utmost relevance. Herein, the potential of MAPK/ERK downregulation by RNAi-based therapeutics in a panel of mesenchymal stem-like TNBC cell lines was uncovered. Our data revealed that suppression of one of the central nodes of this signaling pathway, MEK1, affects proliferation, migration, and invasion of TNBC cells, that may be explained by the reversion of the epithelial-mesenchymal transition phenotype, which is facilitated by the MMP-2/MMP-9 downregulation. Moreover, an …

The Lin28b/Wnt5a Axis Drives Pancreas Cancer Through Crosstalk Between Cancer Associated Fibroblasts And Tumor Epithelium, Zhaoqi Shu, Minghe Fan, Bo Tu, Zhiheng Tang, Haojie Wang, Haimeng Li, Hengchao Li, Meng Yuan, Jingru Bai, Sihan Huo, Lina Wang, Wei-Guo Zhu, Wei Wang, Xiaoyun Liu, Shaokun Shu, Ying Zhao

Faculty, Staff and Student Publications

Bidirectional signal transduction between tumor epithelial cells and tumor microenvironment (TME) is important for tumor development. Here we show that Lin28b/let-7 pathway is indispensable for modulating the expression of Wnt5a in tumor epithelium, which could be secreted and then up-regulates Lin28b in cancer-associated fibroblasts (CAFs). Moreover, we demonstrate that Lin28b in CAFs promoted growth of PDAC by inducing cytokine PCSK9's production. Using an orthotopic mouse model of PDAC, we find that depletion of Lin28b in CAFs reduced tumor weight, highlighting the importance of Lin28b in PDAC stroma. Thus, our study shows that the Lin28b-Wnt5a axis plays a critical role in …

Endocrine Therapy Synergizes With Smac Mimetics To Potentiate Antigen Presentation And Tumor Regression In Hormone Receptor-Positive Breast Cancer, Francisco Hermida-Prado, Yingtian Xie, Shira Sherman, Zsuzsanna Nagy, Douglas Russo, Tara Akhshi, Zhengtao Chu, Avery Feit, Marco Campisi, Minyue Chen, Agostina Nardone, Cristina Guarducci, Klothilda Lim, Alba Font-Tello, Irene Lee, Juana García-Pedrero, Israel Cañadas, Judith Agudo, Ying Huang, Tal Sella, Qingchun Jin, Nabihah Tayob, Elizabeth A Mittendorf, Sara M Tolaney, Xintao Qiu, Henry Long, William F Symmans, Jia-Ren Lin, Sandro Santagata, Isabelle Bedrosian, Denise A Yardley, Ingrid A Mayer, Edward T Richardson, Giacomo Oliveira, Catherine J Wu, Eugene F Schuster, Mitch Dowsett, Alana L Welm, David Barbie, Otto Metzger, Rinath Jeselsohn

Faculty, Staff and Student Publications

Immunotherapies have yet to demonstrate significant efficacy in the treatment of hormone receptor-positive (HR+) breast cancer. Given that endocrine therapy (ET) is the primary approach for treating HR+ breast cancer, we investigated the effects of ET on the tumor immune microenvironment (TME) in HR+ breast cancer. Spatial proteomics of primary HR+ breast cancer samples obtained at baseline and after ET from patients enrolled in a neoadjuvant clinical trial (NCT02764541) indicated that ET upregulated β2-microglobulin and influenced the TME in a manner that promotes enhanced immunogenicity. To gain a deeper understanding of the underlying mechanisms, the intrinsic effects of …

Kunitz-Type Protease Inhibitor Tfpi2 Remodels Stemness And Immunosuppressive Tumor Microenvironment In Glioblastoma, Lizhi Pang, Madeline Dunterman, Songlin Guo, Fatima Khan, Yang Liu, Erfan Taefi, Atousa Bahrami, Changiz Geula, Wen-Hao Hsu, Craig Horbinski, Charles David James, Peiwen Chen

Faculty, Staff and Student Publications

Glioblastoma (GBM) tumors consist of multiple cell populations, including self-renewing glioblastoma stem cells (GSCs) and immunosuppressive microglia. Here we identified Kunitz-type protease inhibitor TFPI2 as a critical factor connecting these cell populations and their associated GBM hallmarks of stemness and immunosuppression. TFPI2 promotes GSC self-renewal and tumor growth via activation of the c-Jun N-terminal kinase-signal transducer and activator of transcription (STAT)3 pathway. Secreted TFPI2 interacts with its functional receptor CD51 on microglia to trigger the infiltration and immunosuppressive polarization of microglia through activation of STAT6 signaling. Inhibition of the TFPI2-CD51-STAT6 signaling axis activates T cells and synergizes with anti-PD1 therapy …

Global Impact Of Somatic Structural Variation On The Cancer Proteome, Fengju Chen, Yiqun Zhang, Darshan S Chandrashekar, Sooryanarayana Varambally, Chad J Creighton

Faculty, Staff and Students Publications

Both proteome and transcriptome data can help assess the relevance of non-coding somatic mutations in cancer. Here, we combine mass spectrometry-based proteomics data with whole genome sequencing data across 1307 human tumors spanning various tissues to determine the extent somatic structural variant (SV) breakpoint patterns impact protein expression of nearby genes. We find that about 25% of the hundreds of genes with SV-associated cis-regulatory alterations at the mRNA level are similarly associated at the protein level. SVs associated with enhancer hijacking, retrotransposon translocation, altered DNA methylation, or fusion transcripts are implicated in protein over-expression. SVs combined with altered protein levels …

Archival Single-Cell Genomics Reveals Persistent Subclones During Dcis Progression, Kaile Wang, Tapsi Kumar, Junke Wang, Darlan Conterno Minussi, Emi Sei, Jianzhuo Li, Tuan M Tran, Aatish Thennavan, Min Hu, Anna K Casasent, Zhenna Xiao, Shanshan Bai, Lei Yang, Lorraine M King, Vandna Shah, Petra Kristel, Carolien L Van Der Borden, Jeffrey R Marks, Yuehui Zhao, Amado J Zurita, Ana Aparicio, Brian Chapin, Jie Ye, Jianjun Zhang, Don L Gibbons, Ellinor Sawyer, Alastair M Thompson, Andrew Futreal, E Shelley Hwang, Jelle Wesseling, Esther H Lips, Nicholas E Navin

Faculty, Staff and Student Publications

Ductal carcinoma in situ (DCIS) is a common precursor of invasive breast cancer. Our understanding of its genomic progression to recurrent disease remains poor, partly due to challenges associated with the genomic profiling of formalin-fixed paraffin-embedded (FFPE) materials. Here, we developed Arc-well, a high-throughput single-cell DNA-sequencing method that is compatible with FFPE materials. We validated our method by profiling 40,330 single cells from cell lines, a frozen tissue, and 27 FFPE samples from breast, lung, and prostate tumors stored for 3-31 years. Analysis of 10 patients with matched DCIS and cancers that recurred 2-16 years later show that many primary …

Vincristine Enhances The Efficacy Of Mek Inhibitors In Preclinical Models Of Kras-Mutant Colorectal Cancer, Susmita Ghosh, Fan Fan, Reid T Powell, Jason Roszik, Yong Sung Park, Clifford Stephan, Manu Sebastian, Lin Tan, Alexey V Sorokin, Philip L Lorenzi, Scott Kopetz, Lee M Ellis, Rajat Bhattacharya

Faculty, Staff and Student Publications

Mutations in KRAS are found in more than 50% of tumors from patients with metastatic colorectal cancer (mCRC). However, direct targeting of most KRAS mutations is difficult; even the recently developed KRASG12C inhibitors failed to show significant benefit in patients with mCRC. Single agents targeting mitogen-activated protein kinase kinase (MEK), a downstream mediator of RAS, have also been ineffective in colorectal cancer. To identify drugs that can enhance the efficacy of MEK inhibitors, we performed unbiased high-throughput screening using colorectal cancer spheroids. We used trametinib as the anchor drug and examined combinations of trametinib with the NCI-approved Oncology Library version …

Zeb1 Is Regulated By K811 Acetylation To Promote Stability, Nurd Complex Interactions, Emt, And Nsclc Metastasis, Mabel Perez-Oquendo, Roxsan Manshouri, Yanhua Tian, Jared J Fradette, B Leticia Rodriguez, Samrat T Kundu, Don L Gibbons

Faculty, Staff and Student Publications

Epithelial-to-mesenchymal transition results in loss of specialized epithelial cell contacts and acquisition of mesenchymal invasive capacity. The transcription repressor zinc finger E-box-binding homeobox 1 (ZEB1) binds to E-boxes of gene promoter regions to suppress the expression of epithelial genes. ZEB1 has inconsistent molecular weights, which have been attributed to posttranslational modifications (PTM). We performed mass spectrometry and identified K811 acetylation as a novel PTM in ZEB1. To define the role of ZEB1 acetylation in regulating function, we generated ZEB1 acetyl-mimetic (K811Q) and acetyl-deficient (K811R) mutant-expressing non-small cell lung cancer cell lines (NSCLC). We demonstrate that the K811R ZEB1 (125 kDa) …

Unique Transcriptional Profiles Underlie Osteosarcomagenesis Driven By Different P53 Mutants, Dhruv Chachad, Lalit R Patel, Carlos Vera Recio, Rasoul Pourebrahim, Elizabeth M Whitley, Wenyi Wang, Xiaoping Su, An Xu, Dung-Fang Lee, Guillermina Lozano

Faculty, Staff and Student Publications

Missense mutations in the DNA binding domain of p53 are characterized as structural or contact mutations based on their effect on the conformation of the protein. These mutations show gain-of-function (GOF) activities, such as promoting increased metastatic incidence compared with p53 loss, often mediated by the interaction of mutant p53 with a set of transcription factors. These interactions are largely context specific. To understand the mechanisms by which p53 DNA binding domain mutations drive osteosarcoma progression, we created mouse models, in which either the p53 structural mutant p53R172H or the contact mutant p53R245W are expressed specifically in osteoblasts, yielding osteosarcoma …

Targeting Cxcr4 Abrogates Resistance To Trastuzumab By Blocking Cell Cycle Progression And Synergizes With Docetaxel In Breast Cancer Treatment, Shuying Liu, Shelly M Xie, Wenbin Liu, Mihai Gagea, Ariella B Hanker, Nguyen Nguyen, Akshara Singareeka Raghavendra, Gloria Yang-Kolodji, Fuliang Chu, Sattva S Neelapu, Adriano Marchese, Samir Hanash, Johann Zimmermann, Carlos L Arteaga, Debasish Tripathy

Faculty, Staff and Student Publications

Background: Although trastuzumab and other HER2-targeted therapies have significantly improved survival in patients with HER2 overexpressed or amplified (HER2+) breast cancer, a significant proportion of patients do not respond or eventually develop clinical resistance. Strategies to reverse trastuzumab resistance remain a high clinical priority. We were the first to report the role of CXCR4 in trastuzumab resistance. The present study aims to explore the therapeutic potential of targeting CXCR4 and better understand the associated mechanisms.

Methods: Immunofluorescent staining, confocal microscopy analysis, and immunoblotting were used to analyze CXCR4 expression. BrdU incorporation assays and flow cytometry were used to analyze dynamic …

Cxcr2 Expression During Melanoma Tumorigenesis Controls Transcriptional Programs That Facilitate Tumor Growth, J Yang, K Bergdorf, C Yan, W Luo, S C Chen, G D Ayers, Q Liu, X Liu, M Boothby, V L Weiss, S M Groves, A N Oleskie, X Zhang, D Y Maeda, J A Zebala, V Quaranta, A Richmond

Faculty, Staff and Student Publications

Background: Though the CXCR2 chemokine receptor is known to play a key role in cancer growth and response to therapy, a direct link between expression of CXCR2 in tumor progenitor cells during induction of tumorigenesis has not been established.

Methods: To characterize the role of CXCR2 during melanoma tumorigenesis, we generated tamoxifen-inducible tyrosinase-promoter driven BrafV600E/Pten-/-/Cxcr2-/- and NRasQ61R/INK4a-/-/Cxcr2-/- melanoma models. In addition, the effects of a CXCR1/CXCR2 antagonist, SX-682, on melanoma tumorigenesis were evaluated in BrafV600E/Pten-/- and NRasQ61R/INK4a-/- mice and in melanoma cell lines. Potential mechanisms by which Cxcr2 affects melanoma tumorigenesis in these murine models were explored using RNAseq, mMCP-counter, …

Targeting Glutaminase Is Therapeutically Effective In Ibrutinib-Resistant Mantle Cell Lymphoma, Lingzhi Li, Lei Nie, Alexa Jordan, Qingsong Cai, Yang Liu, Yijing Li, Yuxuan Che, Jovanny Vargas, Zhihong Chen, Angela Leeming, Wei Wang, Yixin Yao, Michael Wang, Vivian Changying Jiang

Faculty, Staff and Student Publications

Mantle cell lymphoma (MCL) is an incurable B-cell non-Hodgkin lymphoma characterized by frequent relapses. The development of resistance to ibrutinib therapy remains a major challenge in MCL. We previously showed that glutaminolysis is associated with resistance to ibrutinib. In this study, we confirmed that glutaminase (GLS), the first enzyme in glutaminolysis, is overexpressed in ibrutinib-resistant MCL cells, and that its expression correlates well with elevated glutamine dependency and glutaminolysis. Furthermore, we discovered that GLS expression correlates with MYC expression and the functioning of the glutamine transporter ASCT2. Depletion of glutamine or GLS significantly reduced cell growth, while GLS overexpression enhanced …

Usp36 Promotes Tumorigenesis And Drug Sensitivity Of Glioblastoma By Deubiquitinating And Stabilizing Alkbh5, Guoqiang Chang, Gloria S Xie, Li Ma, Peng Li, Linlin Li, Hope T Richard

Faculty, Staff and Student Publications

Background: ALKBH5 is aberrantly activated and exerts critical roles in facilitating the development of glioblastoma. However, the underlying activation mechanism by which ALKBH5 protein is increased in glioblastoma is not completely understood. Our study aimed to elucidate the signaling pathways involved in mediating ALKBH5 protein stability.

Methods: The contribution of deubiquitinating enzymes (DUB) to the fluctuation of ALKBH5 protein expression was globally profiled with western blot analysis. Mass spectrometry and immunoprecipitation were performed to identify the USP36 and ALKBH5 interaction. The effects of USP36 on the stability of ALKBH5 were detected with in vivo and in vitro ubiquitination assays. Cell …

Emp1+ Tumor Cells Drive Metastatic Relapse, Oscar E Villarreal, Scott Kopetz

Faculty, Staff and Student Publications

No abstract provided.

Mmp9 Clears The Way For Metastatic Cell Penetration Across The Blood-Brain Barrier, Joseph H Mccarty

Faculty, Staff and Student Publications

Although brain metastases are 10-fold more prevalent than primary brain cancers, relatively little is understood about the genes and pathways that promote metastatic cell entry, growth, and survival in the brain. Hence, determining how metastatic tumors colonize the brain and thrive within the neural microenvironment is a topic of both fundamental importance and direct clinical relevance. In this issue, a report by Karreman and colleagues explores pathways that are exploited by metastatic tumor cells to arrest in the circulation, cross the endothelial blood-brain barrier (BBB), and thrive in the brain microenvironment. The authors used elegant imaging tools including intravital fluorescence …