Medical Sciences Commons^™

Steroid Receptor Coactivator 3-Deficient Regulatory T Cells Eradicate Multiple Solid Tumors In Syngeneic Mouse Models, Nuri Sung, Eunsu Kim, Yosef Gilad, Yuri Park, Adam M Dean, Yan Xia, Jianming Xu, Clifford C Dacso, David M Lonard, Sang Jun Han

Faculty, Staff and Students Publications

Steroid receptor coactivator 3 (SRC-3) is highly expressed in regulatory T cells (Tregs) and is important for their immunosuppressive activity. Recently, we demonstrated that disrupting SRC-3 expression in Tregs eliminates triple-negative breast cancer (TNBC) and prostate cancer in syngeneic animal models by generating an anti-tumor immune microenvironment without inducing immune-related adverse events (irAEs). Further analysis of these mice revealed that SRC-3 knockout (KO) Tregs infiltrated breast tumors and facilitated the infiltration of CD8

Cigarette Smoke Induces Fasn-Dependent Fatty Acid Metabolic Rewiring To Drive Bladder Cancer Progression, Chandra Sekhar Amara, Danthasinghe Waduge Badrajee Piyarathna, Abu Hena Mostafa Kamal, Yuen San Chan, Karthik Reddy Kami Reddy, Chandra Shekar R Ambati, Mohammed Khurshidul Hassan, Pratik Shriwas, Tanmay Gandhi, Antrix Jain, Tanja Gangnus, Pooja Popli, Roshan Borkar, Sung Wook Kang, Silvia L Summers, Vasanta Putluri, Sandra L Grimm, Sharan Venkatesh, Ningxin Song, Erin H Seeley, Jenna Hedlich-Dwyer, Shu-Hsia Chen, Nupam P Mahajan, Abhinav K Jain, Lacey Elizabeth Dobrolecki, Gabrielle A Wells, Hugo Villanueva, Jenny Li, Xuefeng Liu, Roni J Bollag, Anna Malovannaya, Sung Yun Jung, Hyun-Sung Lee, Irfan A Asangani, Martha K Terris, Chad J Creighton, Leomar Y Ballester, Balasubramanyam Karanam, Suyu Liu, Minjae Lee, Rajeeva R Raju, M Minhaj Siddiqui, Livia S Eberlin, Ramakrishna Kommagani, Arun Sreekumar, Jianjun Gao, Nicolas L Young, H Courtney Hodges, Cristian Coarfa, Natalie R Gassman, Seth P Lerner, Yair Lotan, Nagireddy Putluri

Faculty, Staff and Students Publications

Cigarette smoke promotes bladder tumor growth by enhancing cancer cell survival and proliferation through smoke mediated carcinogens. FASN, a key enzyme in fatty acid synthesis, is dysregulated in many cancers and correlates with aggressive phenotypes. In this study, we demonstrate elevated fatty acid levels and FASN specifically in smokers with bladder cancer. Elevated FASN under smoke exposure imparted epigenetic alterations, particularly histone acetylation, impacts DNA repair and DNA-binding transcription factors which regulate metabolic pathways. Under cigarette smoke, bladder cancer cells undergo a metabolic shift, utilizing glutamine as a major carbon source through reductive carboxylation to fuel fatty acid biosynthesis via …

Notch Signaling Regulates The Secretion Of Pro-Metastatic Factors In Extracellular Vesicles In Liposarcoma, Menchus Quan, Yi-Kai Liu, Ying Zhao, Madeline Kay, Kai Sun, Timothy P Gavin, Raphael E Pollock, W Andy Tao, Shihuan Kuang

The Brown Foundation: Institute of Molecular Medicine

Notch signaling is an emerging regulator of liposarcoma (LPS), but its role in mediating communication with the tumor microenvironment (TME) is unclear. Here, we investigate how Notch activation (NICD overexpression) alters the proteomes of LPS-derived extracellular vesicles (EVs). We used quantitative mass spectrometry to profile the EV proteome in multiple contexts: cultured LPS cells, LPS tumor, circulating EVs of LPS-bearing mice, and human LPS samples. We found that Notch signaling increases the secretion of EV proteins that favor tumor progression and metastasis but suppresses immune responses in murine LPS cells. Overlapping murine and human LPS data identifies 18 proteins that …

Unbiased Avidity-Based Isolation Of Antigen-Specific T Cells, Amanda Montoya, Meredith L Frank, Peixin Jiang, Hui Nie, Minying Zhang, Emily Bontekoe, Jared K Slone, Ludovica L Posta, Sofia Rosy Caterina Sorice, Tina Cascone, Maura Gillison, Don L Gibbons, Jianjun Zhang, Eleonora Dondossola, Lydia Kavraki, Pamela L Wenzel, John V Heymach, Alexandre Reuben

The Brown Foundation: Institute of Molecular Medicine

Background: Cancer immunotherapies have significantly improved treatment efficacy and patient survival by exploiting antigen-specific T cells to eliminate cancer cells. However, current approaches for identifying and isolating antigen-specific T cells typically require prior knowledge of target antigens, limiting discovery, and reducing the ability to consistently detect rare tumor-reactive T cells. We therefore sought to develop an unbiased platform for the identification and enrichment of antigen-specific T cells using naturally processed and presented tumor antigens.

Methods: We developed ATTACH (Assessment of T cells Tethered to Antigen Class I Histocompatibility), a microfluidic platform that applies controlled shear stress and leverages tumor cells …

Chemotherapeutic Induction Of Cytosolic Single-Stranded Dna Accumulation Sensitizes Triple-Negative Breast Cancer To Immunotherapy, Yong Du, Li Yang, Hui Dai, Jianli Zhou, Zhicheng Zhou, Ruoxi Yuan, Rui Ye, Anh Thai Quynh Nguyen, Kishor Bhatia, Shiaw-Yih Lin

Faculty, Staff and Students Publications

Background: Despite the widespread adoption of chemoimmunotherapy in triple-negative breast cancer (TNBC), the mechanisms by which cytotoxic chemotherapy engages antitumor immunity remain poorly defined. Identifying tumor-intrinsic immunogenic programs that predict and enhance responsiveness to immune checkpoint blockade (ICB) is therefore of critical clinical importance.

Methods: Transcriptomic signatures of TREX1 deficiency were generated from CRISPR-engineered TNBC models and applied to multiple independent TNBC cohorts treated with chemoimmunotherapy. Cytosolic single-stranded DNA (ssDNA) accumulation was quantified using a flow cytometry-based assay to functionally screen chemotherapeutic agents. Immune activation and therapeutic efficacy were evaluated using in vitro assays, syngeneic mouse tumor models, flow cytometry, …

In Vivo Orf Overexpression Screening Identifies Ccn4 As A Regulator Of Glioblastoma Growth Validated Across Multiple Models, Pushan Dasgupta

Faculty, Staff and Students Publications

Despite current multimodal therapies for glioblastoma (GBM), its prognosis remains grim. Thus, a tremendous need exists to identify new genetic drivers that may serve as potential therapeutic targets in glioblastoma (GBM). We describe an in vivo overexpression screening strategy to identify drivers of glioblastoma where we have leveraged TCGA datasets to conduct a functional genomics screen of prioritized open reading frames (ORFs) that are overexpressed and/or amplified in GBM. To interrogate these potential drivers within a more relevant physiological context, the screening was accomplished in vivo in an orthotopic patient-derived glioma stem-like cell (GSC) model. Among 5 positive "hits" from …

Notch1 Acts As A Tumor Suppressor That Induces Early Differentiation In Head And Neck Cancer, Chenfei Huang, Shhyam Moorthy, Qiuli Li, Kazi M Ahmed, Kalil Saab, Defeng Deng, Jiping Wang, Xiayu Rao, Jiexin Zhang, Yuanxin Xi, Jing Wang, Zhiyi Liu, Noriaki Tanaka, David A Wheeler, Eve Shinbrot, Rami Saade, Curtis R Pickering, Tong-Xin Xie, Adel K El-Naggar, Abdullah A Osman, Kunal Rai, Patrick A Zweidler-Mckay, John V Heymach, Lauren A Byers, Faye M Johnson, Vlad C Sandulache, Jeffrey N Myers, Pedram Yadollahi, Mitchell J Frederick

Faculty, Staff and Students Publications

Inactivating NOTCH1 mutations in head and neck squamous cell carcinoma (HNSCC) were described over a decade ago, suggesting a tumor suppressor function - unlike its oncogenic role in other tumors. Today, much debate persists regarding a putative oncogenic role in HNSCC as well, with reports that NOTCH1 signaling drives tumor growth and a cancer stem cell (CSC) phenotype. In this work, comprehensive experiments unequivocally demonstrate that NOTCH1 is a tumor suppressor in HNSCC regardless of mutation or activation status and that it reduces CSC frequency. We developed a signature of NOTCH1 activation showing the pathway is associated with very early …

Histone Deacetylase Enzyme Activity Is Not The Universal Anticancer Target Of Hdac Inhibitors, Chaitra Rai, Hang Ruan, Xue Li, Wenbo Li, Hyun-Hwan Jeong, Chengchuang Song, Panpan Liu, Yingjie Chang, Hao Fang, Udhaya Kumar S, Yuxiang Sun, M James You, Dongyin Guan, Zhandong Liu, Leng Han, Xuben Hou, Zheng Sun

Faculty, Staff and Students Publications

Histone deacetylase inhibitors (HDIs) are approved for treating hematologic cancers and are currently being evaluated in hundreds of clinical trials for various cancers and other diseases, although their mechanisms of action remain poorly understood. Here, our unbiased bioinformatics analyses found that, for most cancer types, expression levels or genetic variants of histone deacetylase (HDACs) do not consistently correlate with carcinogenesis, do not predict cancer patient survival, and do not associate with cellular responses to HDIs. Whole-genome CRISPR library screens did not identify HDACs as genes affecting cellular responses to HDIs. Overexpression of dominant-negative Class I HDACs causes similar protein hyperacetylation …

Monoclonal Antibodies Targeting Pcdh7 Inhibit Tumor Growth And Enhance Immune Responses In Kras-Mutant Non-Small Cell Lung Cancer, Nicole Novaresi, Poorva Ghosh, Shayna Thomas-Jardin, Hui Deng, Xuejun Fan, Zhiqiang Ku, Wei Xiong, Xiaorong Zhou, Jingfei Zhu, Huiyu Li, Mahesh S Padanad, Bethany Smith, Chul Ahn, John D Minna, Zhiqiang An, Ningyan Zhang, Kathryn A O'Donnell

The Brown Foundation: Institute of Molecular Medicine

We identified an important oncogenic role for protocadherin 7 (PCDH7), a cell surface protein frequently overexpressed in lung adenocarcinoma and associated with poor clinical outcome. Pcdh7 depletion reduces tumor burden and prolongs survival in KrasLSL-G12D; Tp53fl/fl mice. These findings nominate this cell surface protein as an actionable therapeutic target and highlight the therapeutic potential of PCDH7 inhibition for non–small cell lung cancer. We report the development and characterization of high-affinity anti-PCDH7 monoclonal antibodies (mAbs) that inhibit downstream mitogen-activated protein kinase (MAPK) pathway activation and suppress tumor growth in multiple mutant KRAS–driven models. A lead mAb (mAb7) sensitized tumors …

Loss Of Znrf3/Rnf43 Unleashes Egrfr In Cancer, Fei Yue, Amy T Ku, Payton D Stevens, Megan N Michalski, Weiyu Jiang, Jianghua Tu, Zhongcheng Shi, Yongchao Dou, Yi Wang, Xin-Hua Feng, Galen Hostetter, Xiangwei Wu, Shixia Huang, Noah F Shroyer, Bing Zhang, Bart O Williams, Qingyun Liu, Xia Lin, Yi Li

Faculty, Staff and Students Publications

ZNRF3 and RNF43 are closely related transmembrane E3 ubiquitin ligases with significant roles in development and cancer. Conventionally, their biological functions have been associated with regulating WNT signaling receptor ubiquitination and degradation. However, our proteogenomic studies have revealed EGFR as the protein most negatively correlated with ZNRF3/RNF43 mRNA levels in multiple human cancers. Through biochemical investigations, we demonstrate that ZNRF3/RNF43 interact with EGFR via their extracellular domains, leading to EGFR ubiquitination and subsequent degradation facilitated by the E3 ligase RING domain. Overexpression of ZNRF3 reduces EGFR levels and suppresses cancer cell growth in vitro and in vivo, whereas knockout of …

A Multidomain Peptide Hydrogel-Liposome Composite For Controlled Release Of A Cyclic Dinucleotide In Oral Cancer, Joseph W R Swain, Andrea H Molina, Gemalene M Sunga, Danielle Chew-Martinez, Neeraja Dharmaraj, Alejandra Cobos Perez, Arghadip Dey, Ephraim J Vázquez-Rosado, Simon Young, Jeffrey D Hartgerink

Faculty, Staff and Student Publications

While immunotherapy is a promising treatment strategy for cancer, the majority of head and neck squamous cell carcinoma (HNSCC) patients treated with single-agent immunotherapy do not respond. Therefore, researchers are investigating combination treatments with immunostimulatory molecules that can maximize anti-tumor responses. Cyclic dinucleotides (CDNs) are STING agonists that hold promise in combination approaches, but they require frequent intratumoral administration when used in both preclinical models of HNSCC and clinical trials. To reduce administration frequency, we have created a peptide hydrogel–liposome composite system, K2-Lip(CDN), for local and prolonged availability of CDN. We investigated the loading limits of cationic liposomes in both …

Co-Occurrence Of Transcriptionally Distinct Persister Cell States Underpins Neoadjuvant Therapy Resistance In Triple-Negative Breast Cancer, Yu Zhang, Fatemeh Ahmadi Moughari, Ioanna Mavrommati, Nora J Doleschall, Kate Moore, Gareth Muirhead, Ram Rajaram Srinivasan, Ping Gong, Jonathan T Lei, Amy Fleming, Hwei Minn Khoo, Naomi Guppy, Gabrielle Elshtein, Mohammed Inayatullah, Vijay K Tiwari, Lacey E Dobrolecki, Michael T Lewis, Syed Haider, Rachael Natrajan

Faculty, Staff and Students Publications

Background

Although the addition of neoadjuvant immune checkpoint blockade to chemotherapy has improved patient outcome in early triple‑negative breast cancer (TNBC), some patients continue to have poor disease outcomes.

Methods

To characterise neoadjuvant chemotherapy (NAC) resistant cell populations that persist post-NAC, we created a high-resolution single-cell atlas of 129,433 cells from fourteen TNBC patient-derived xenograft (PDX) models with residual disease post-NAC. We identified transcriptionally distinct cancer subpopulations or cell states using unsupervised clustering and characterised‑ their regulatory network as well as clinical associations with treatment response, metastatic progression and survival. Findings were validated using multiple independent TNBC cohorts.

Results

Four …

Claudins Interact With Lilrb Immune Inhibitory Receptors To Promote Myeloid Immunosuppression In Cancer, Xiaoye Liu, Ryan Huang, Zhiqiang Ku, Jingjing Xie, Heyu Chen, Yubo He, Qi Lou, Chengcheng Zhang, Xing Yang, Cheryl Lewis, Jade Homsi, Ankit Gupta, Lei Dong, Kenian Chen, Annabel Tu, Liming Du, Hailong Yu, Qing Hu, Meng Fang, Bufan Li, A E M Adan Khan, Caroline Simith, Samuel John, Lin Xu, Ningyan Zhang, Zhiqiang An, Cheng Cheng Zhang

The Brown Foundation: Institute of Molecular Medicine

The mechanisms underlying tumor cell-myeloid cell interactions in the tumor microenvironment (TME) remain unclear, and predictive biomarkers for patient response to myeloid checkpoint blockade are lacking. This study identified specific binding between tight junction claudins (CLDNs) and leukocyte immunoglobulin-like receptor subfamily B2 (LILRB2) and LILRB5. In multiple human cancer cohorts, the spatial proximity of LILRB2-positive macrophages to CLDN-expressing cancer cells correlated with clinical outcomes, highlighting this spatial relationship as a potential biomarker. In syngeneic LILRB2-transgenic and humanized mouse models, CLDN18.2-LILRB2 interactions triggered bidirectional signaling, enhanced the immunosuppressive activity of myeloid cells, and accelerated tumor progression. These effects were reversed by …

Ins-17 Acts As A Nutrient Deprivation Signal To Mediate Adult Iis-Regulated Associative Behaviors In C. Elegans, Emily J Leptich, Priyadharshini Vijayakumar, Edward W Pietryk, Meredith I Williams, Rachana Rajupalem, Rachel N Arey

Faculty, Staff and Students Publications

Insulin/Insulin-like growth factor 1 (IGF-1) signaling (IIS) is a pleiotropic signaling pathway that functions across tissues to coordinate phenotypic changes in response to nutrient status. Thus, the ubiquity of the IIS pathway hinders efforts to elucidate the mechanisms driving specific IIS-related phenotypes. Previous research in the nematode worm C. elegans has demonstrated that loss of function of the IIS transmembrane receptor (IR) ortholog, DAF-2, results in a doubled lifespan and enhanced learning and memory behaviors in young and aged animals. However, these findings are the result of reducing DAF-2 receptor function rather than modulating ligand-receptor interactions. In the current study, …

Multiparametric Mri To Predict Response To Irreversible Electroporation Plus Anti-Pd-1 Immunotherapy In Pancreatic Ductal Adenocarcinoma, Qizhen Cao, Mark D Pagel, Charles V Kingsley, Jingfei Ma, James P Long, Xiaoxia Wen, Seth T Gammon, Jorge Delacerda, Sanaz Javadi, Chun Li

Faculty, Staff and Student Publications

Purpose: To investigate contrast-enhanced T1-weighted MRI and diffusion-weighted magnetic resonance imaging (DWI) for early prediction of tumor response to combined irreversible electroporation (IRE) and anti-PD-1 immunotherapy.

Methods: Murine pancreatic ductal adenocarcinoma (PDAC) cells KRAS* were inoculated into the pancreas of C57BL/6 mice. IRE was performed when tumors became palpable. After IRE, mice received six intraperitoneal injections of anti-PD-1 over 2 weeks. T2-weighted MRI, T1-weighted MRI with macromolecular contrast agent poly(L-glutamic acid)-conjugated gadolinium (PG-Gd), and DWI were performed before and after IRE. Survival was analyzed using Kaplan-Meier curves. Mice surviving at least 100 days without recurrence after IRE were considered complete …

Gompertz Growth With A Shared Carrying Capacity Optimally Simulates Primary And Metastatic Tumor Growth Dynamics, Pirmin Schlicke, Preethi Korangath, Xiaoxi Pan, Caner Ercan, Kathleen Gabrielson, Lyndsey Werhane, Yinyin Yuan, Sébastien Benzekry, Robert Ivkov, Heiko Enderling

Faculty, Staff and Student Publications

Background: Cancer is a systemic disease with most deaths attributed to metastatic burden. Primary and metastatic tumors, albeit at different anatomic locations, are interconnected through multiple biological processes. Pre-clinical and clinical observations of growth acceleration of metastases after surgery, or abscopal effects outside the radiation field are widely reported, yet reliably triggering favorable and avoiding unfavorable systemic responses remains an unmet clinical need. Understanding local and systemic tumor interaction dynamics will help guide future treatments.

Methods: We analyze the data of multiple in vivo tumor models. We formalize the systemic interplay of tumors as mathematical differential equation and calibrate parameters …

The Hexosamine Biosynthetic Pathway Alters The Cytoskeleton To Modulate Cell Proliferation And Migration In Aggressive Prostate Cancer, Rajina Shakya, Praveen Suraneni, Amit Rahi, Michael Y Young, Emily Cousino, Christine B Magdongon, Raju Gajjela, Basil B Mattamana, Alexander Zaslavsky, Ganesh S Palapattu, Arun Sreekumar, Dileep Varma

Faculty, Staff and Students Publications

Castration-resistant prostate cancer (CRPC) progresses despite androgen deprivation therapy, as cancer cells adapt to grow without testosterone, becoming more aggressive and prone to metastasis. CRPC biology complicates the development of effective therapies, posing challenges for patient care. Recent gene-expression and metabolomics studies highlight the Hexosamine Biosynthetic Pathway (HBP) as a critical player, with key components like GNPNAT1 (Glucosamine-phosphate N-acetyltransferase 1) being downregulated in CRPC. GNPNAT1 knockdown in pre-clinical models has been shown to increase growth and metastasis in CRPC tumors, though the mechanisms remain unclear.To investigate the cellular basis of these CRPC phenotypes, we generated a CRISPR-Cas9 knockout model of …

Poly(Adp-Ribose) Glycohydrolase Enforces P21 Degradation Via Deparylation To Promote Gastric Cancer Progression, Yangchan Hu, Qimei Bao, Yixing Huang, Yan Wang, Xin Zhao, Junjun Nan, Yuxin Meng, Mingcong Deng, Yuancong Li, Zirui Zhuang, Hanyi He, Dan Zu, Yuke Zhong, Chunkai Zhang, Bing Wang, Ran Li, Yanhua He, Qihan Wang, Min Liu, John A Tainer, Yin Shi, Xiangdong Cheng, Ji Jing, Zu Ye

Faculty, Staff and Student Publications

Dysregulation of cell cycle checkpoints is a cancer hallmark, with ubiquitination-controlled protein stability playing a pivotal role. Although p21, a key cyclin-dependent kinase inhibitor, is tightly regulated by ubiquitin-mediated degradation, the key upstream modulators of its ubiquitination remain incompletely defined. Here, we identify poly(ADP-ribose) glycohydrolase (PARG) as a regulator of p21 stability in gastric cancer (GC) cells. We show that PARG expression is markedly upregulated in GC tissues and correlates with poor patient prognosis. Functional assays revealed that genetic depletion of PARG triggers G2/M phase arrest and impairs GC cell proliferation. Mechanistically, we demonstrate that PARG loss enhances p21 PARylation, …

Cd44v9 As A Therapeutic Target For Antibody-Drug Conjugate In Advanced Breast Cancer, Dileep R Reddy, Mckenna E Flynn, Yasuaki Anami, Zhaoxuan Yang, Jayden Aleman, Minji Seo, Kyoji Tsuchikama, Jennifer A Maynard, Naoto T Ueno, Jangsoon Lee

Faculty, Staff and Student Publications

Antibody-drug conjugates (ADCs) have revolutionized breast cancer therapy. HER2 is the only validated biomarker guiding ADC therapy in breast cancer. However, their clinical benefit remains confined to HER2- and TROP2-targeted therapies. Tumor heterogeneity and acquired resistance often limit durable responses, underscoring the need for novel, tumor-specific ADC targets. CD44 variant isoform 9 (CD44v9), a splice variant of the CD44 family, is largely absent in normal tissues but enriched in aggressive breast cancers, where it contributes to stemness, redox regulation, and therapy resistance. In this study, we developed a chimeric monoclonal antibody against CD44v9 (clone SUM24.1, IgG1) and conjugated it to …

Fgl2-Knockout Tumor Cells Serve As A Vaccine Inducing Long-Duration Brain-Resident Memory T Cells That Reject Subsequent Intracranial Tumor Cell Challenges, Sheng Zhang, Yining Jin, Zhiliang Jia, Xueqing Xia, Yang Li, Qi Wang, Jing Wang, Jian Wang, Joya Chandra, Gregory K Friedman, Shulin Li

Faculty, Staff and Student Publications

The failure to prevent brain tumors, including both recurrent primary and metastatic brain tumors, is the primary cause of patients' mortality. We developed a novel whole tumor-cell vaccine to rapidly induce long-duration brain-resident memory T (TRM) cells that prevent brain tumor progression. Ten Fgl2-KO primary and metastatic tumor cell lines, generated via CRISPR/Cas9, were used to vaccinate mice and for intracranial challenges with the WT tumor cells. Not only did vaccinated mice reject these tumor cell challenges, but also more than half of these mice became long-duration survivors. Transplanting brain immune cells from vaccinated mice into naïve mice enabled this …

Celf1 Is A Non-Canonical Eif4e Binding Protein That Promotes Translation Of Epithelial-Mesenchymal Transition Effector Mrnas, Arindam Chaudhury, Natee Kongchan, Shebna A Massey, Rajesh Sharma, Rituraj Pal, Na Zhao, Phoebe Tsoi, Yingmin Zhu, Emuejevoke Olokpa, Sufeng Mao, Sonia Del Rincon, Lucas C Reineke, Richard E Lloyd, Marco Sardiello, Jeffrey M Rosen, Choel Kim, Josephine C Ferreon, Joel R Neilson

Faculty, Staff and Students Publications

Mounting evidence is revealing an increasing complexity of gene regulation at the level of messenger RNA (mRNA) translation. Within mammalian cells, canonical cap-dependent mRNA translation depends on the eIF4F complex, consisting of the m7G mRNA cap-binding protein eukaryotic initiation factor 4E (eIF4E), the helicase eIF4A (eIF4A), and the eIF4G (eIF4G1) scaffolding protein. eIF4G1 additionally binds poly(A) binding protein (PABPC1) to facilitate mRNA circularization and nucleates pre-translation initiation complex assembly to initiate ribosomal scanning. In breast epithelial cells, the CELF1 RNA-binding protein specifically promotes the translation of select epithelial-to-mesenchymal transition (EMT) effector mRNAs by binding GU-rich elements (GREs) within their 3' …

Syndecan-1-Targeted Therapeutic Antibody Impairs Macropinocytosis And Elicits Antitumor Immunity In Pancreatic Cancer, Zecheng Yang, Madelaine S Theardy, Shuaitong Chen, Yongkun Wei, Mitsunobu Takeda, Yue Zeng, Xiaofei Wang, Jun Yao, Jennifer Li, Prapassorn Thirasastr, Jangho Park, Yangxi Zheng, Long T Vien, Khalida M Wani, Huamin Wang, Sisi Gao, Tim Heffernan, Lawrence Kwong, Ignacio I Wistuba, Laura Bover, Giulio F Draetta, Haoqiang Ying, Wantong Yao

Faculty, Staff and Student Publications

Pancreatic ductal adenocarcinoma (PDAC) remains one of the deadliest malignancies, with a 5-year survival rate of just 13%. While the development and early clinical use of small molecules targeting oncogenic KRAS mutations, key drivers of PDAC, have shown promise, resistance to these targeted therapies remains a significant challenge. We recently identified Syndecan-1 (SDC1), a highly expressed heparan sulfate proteoglycan, as a critical KRAS effector protein that promotes nutrient salvage and tumor growth. Here, we report the development of a human-specific monoclonal antibody (anti-SDC1 mAb) that inhibits PDAC cell proliferation in vitro and suppresses PDAC tumor growth in vivo. Mechanistically, …

Sting-Induced Blood-Brain Barrier Opening Combined With Radiotherapy Potentiates Antitumor Response In A High-Grade Glioma Model, Shashwat Tripathi, Hinda Najem, Lisa Hurley, Ruochen Du, Crismita Dmello, Heba Ali, Kathleen Mccortney, Karl J Habashy, Peng Zhang, Craig M Horbinski, Lara Leoni, Ryan J Avery, Rimas V Lukas, Timothy L Sita, David R Raleigh, Sean Sachdev, Roger Stupp, Maciej S Lesniak, David M Ashley, Daniele Procissi, Michael A Curran, Irina Balyasnikova, Amy B Heimberger

Faculty, Staff and Student Publications

Radiation therapy (RT) is the standard of care for glioblastoma but is not curative. Triggering the cGAS/stimulator of interferon genes (STING) pathway with potent agonists, such as 8803, exerts activity across high-grade glioma preclinical models. To determine if the combination of 8803 with RT warrants consideration in the up-front treatment setting and to clarify the underlying mechanisms of therapeutic activity, C57BL/6J mice harboring intracerebral CT-2A or QPP8v gliomas were treated with RT, intratumoral 8803, or both. The treatment with the combination resulted in 80% long-term survival in the CT-2A model but not in the radiation-resistant QPP8v model. This therapeutic effect …

Ubiquitination-Directed Cytosolic Dna Degradation Governs Cgas-Sting-Mediated Immune Response To Dna Damage, Lei Li, Qi Ye, Jinlu Ma, Zixi Wang, Tianjie Liu, Yuzeshi Lei, Mingming Lu, Jialu Kang, Haohan Xiang, Buyun Li, Shan Xu, Ke Wang, Yule Chen, Jiaqi Chen, Bohan Ma, Wenyue Huang, Mengjiao Cai, Nan Wu, Yanqiang Li, Jiale An, Chongming Jiang, Rui Ye, Jing Liu, Steven H Lin, Yang Gao, Jian Ma, Lei Li

Faculty, Staff and Student Publications

Activation of cGAS-STING signaling in cancer cells requires cytosolic DNA produced by intrinsic or treatment-induced DNA damage. However, clinical efforts to exploit this pathway to improve immunotherapy have yielded limited success, highlighting gaps in understanding the link between DNA damage and immunotherapy. Here, we identify ubiquitination-directed cytosolic DNA degradation as a critical determinant for cGAS-STING activation following DNA damage. Mechanistically, the cytosolic DNA exonuclease TREX1 is degraded by the E3 ubiquitin ligase SPOP but is reversely stabilized by the deubiquitinase USP7. Cancer-associated SPOP mutations or USP7 overexpression elevate TREX1 levels, promoting cytosolic DNA degradation and impairing cGAS-STING-mediated immune activation. Notably, …

Extracellular Matrix Mediates Circulating Tumor Cell Clustering In Triple-Negative Breast Cancer Metastasis, Georg Om Bobkov, Khushali J Patel, Bree M Lege, Rong Zheng, Gad Shaulsky, Matthew J Ellis, Chonghui Cheng

Faculty, Staff and Students Publications

Metastatic tumor cell dissemination is the leading cause of cancer-related deaths. Clustered circulating tumor cells (CTCs) possess higher metastatic potential than single CTCs. Epithelial adherens junction (AJ) proteins typically mediate stable cell-cell interactions; however, these proteins are frequently lost in highly aggressive triple-negative breast cancers (TNBCs), raising the question of how CTCs from such tumors cluster. Here we show that the extracellular matrix (ECM) component hyaluronan (HA) mediates AJ-independent CTC clustering in TNBCs. HA is necessary and sufficient to drive clustering of tumor cells expressing its receptor CD44. Mechanistically, HA initiates contact between neighboring cells through actin-based membrane protrusions. As …

Ubiquitination Of Oncogenic Mutant P53 Via Attenuation Of Ribosome Biogenesis Machinery Effectively Inhibits Pancreatic Tumor Growth, Mudassier Ahmad, Sahir Sultan Alvi, Haider Ahsan, Carlos Perez, Andrew Massey, Vivek K Kashyap, Neeraj Chauhan, Emmanuel Anning, Manish K Tripathi, Dae J Kim, Nirakar Sahoo, Tamer Oraby, Murali M Yallapu, Mohammad Moshahid Khan, Manu M Sebastian, Subhash C Chauhan, Bilal B Hafeez

Faculty, Staff and Student Publications

Dysregulated ribosome biogenesis and p53 mutations are known to play oncogenic roles in various cancers, including pancreatic cancer. In this study, we demonstrated the therapeutic potential of BMH-21, a pharmacologic inhibitor of RNA polymerase I, against pancreatic cancer by uncovering a novel molecular mechanism involving RPA194-mediated ubiquitination of mutant p53 without affecting the ubiquitination of wild-type p53. Our key findings are that (i) BMH-21 selectively induces apoptosis and cell growth inhibition of pancreatic cancer cells with no effect on normal human pancreatic ductal epithelial cells; (ii) BMH-21 degrades RPA194; (iii) BMH-21 inhibits recruitment of both RPA194 and RPA135 on rDNA …

Osimertinib Activates A Tgf-Β2-Dependent Secretory Program That Drives Lung Adenocarcinoma Progression, Madhurima Ghosh, Chao Wu, Abhishek Kumar, Monique Nilsson, John V Heymach, Weina Zhao, Jiang Yu, Xin Liu, Na Ding, Shike Wang, Guan-Yu Xiao, Angelo Chen, Kate Grimley, William K Russell, Chad J Creighton, Xiaochao Tan, Jonathan M Kurie

Faculty, Staff and Student Publications

EGFR-mutant lung adenocarcinomas (LUADs) that are vulnerable to the EGFR antagonist osimertinib (Osi) eventually relapse, owing in part to the emergence of drug-tolerant persister (DTP) cells that arise through epigenetic mechanisms. Intratumoral DTP cells can herald a worse clinical outcome, but the way in which DTP cells influence LUAD progression remains unclear. Osi-resistant (OR) cells exhibit typical DTP cell features, including a propensity to undergo senescence and epithelial-mesenchymal transition (EMT), which can activate heightened secretory states. Therefore, we postulated that OR cells influence LUAD progression through paracrine mechanisms. To test this hypothesis, we utilized congenic pairs of EGFR-mutant LUAD cell …

Cd8+ T Cells In The Tumor Microenvironment Modulate The Response To Endocrine Therapy In Breast Cancer, Fabiana Napolitano, Yunguan Wang, Dhivya R Sudhan, Paula I Gonzalez-Ericsson, Luigi Formisano, Nisha Unni, Shahbano Shakeel, James Z Zhu, Khushi Ahuja, Lei Guo, María Rosario Chica-Parrado, Yuki Matsunaga, Pamela Luna, Chang-Ching A Lin, Yasuaki Uemoto, Kyung-Min Lee, Hongli Ma, Nathaniel J Evans, Alberto Servetto, Saurabh Mendiratta, Spencer D Barnes, Roberto Bianco, Yisheng V Fang, Lin Xu, Jeon Lee, Tao Wang, Justin M Balko, Gordon B Mills, Marilyne Labrie, Ariella B Hanker, Carlos L Arteaga

Faculty, Staff and Student Publications

The role of the tumor immune microenvironment (TIME) in modulating responses to antiestrogen therapy in hormone receptor-positive (HR+) breast cancers remains unclear. We analyzed pre- and on-treatment biopsies from patients with HR+ breast cancer treated with letrozole to induce estrogen deprivation (ED). Stromal tumor-infiltrating lymphocytes, assessed by H&E staining, and immune-related gene sets, including IFN-γ signaling genes, measured by RNA-Seq, were increased in ED-resistant tumors. Cyclic immunofluorescence and spatial transcriptomics revealed an abundance of CD8+ T cells and enhanced antigen processing and immune gene signatures in ED-resistant tumors. In this group, the expression of CXCL9, CXCL10, and CXCL11 - chemokine …

Local Delivery Of Mir-27a* Using Ultrasound-Targeted Microbubble Cavitation Inhibits Squamous Cell Carcinoma Growth, Nikhil S Chari, Cheng Chen, Thiruganesh Ramasamy, Xucai Chen, Geetika Wadhwa, Anurag N Paranjape, Stephen Y Lai, Flordeliza S Villanueva

Faculty, Staff and Student Publications

Objective: Ultrasound-targeted microbubble (MB) cavitation (UTMC) is an image-guided therapeutic oligonucleotide delivery platform utilizing intravenously injected gas-filled ultrasound contrast agents, which carry the therapeutic on the MB shell. During transit of MBs in the microcirculation of target tissue, ultrasound causes MB oscillation, facilitating endocytosis-independent payload uptake within insonified cells. Here, we tested the hypothesis that UTMC-mediated miR-27a* delivery will reduce tumor growth rate and result in accumulation of miR-27a* within tumor cells and the tumor microenvironment.

Methods: We used UTMC to deliver miR-27a* to SCC-VII cells in vitro and in SCC-VII mouse tumor models. Pulsed ultrasound was delivered during intravenous …

Identification Of Raptor And Gli1 As Usp37 Substrates Highlight Its Context-Specific Function In Medulloblastoma Cells, Ashutosh Singh, Donghang Cheng, Amanda R Haltom, Yanwen Yang, Tara Dobson, Rashieda Hatcher, Veena Rajaram, Vidya Gopalakrishnan

Faculty, Staff and Student Publications

The USP37 gene encodes a deubiquitylase (DUB), which catalyzes the proteolytic removal of ubiquitin moieties from proteins to modulate their stability, cellular localization or activity. Its expression is downregulated in a subgroup of medulloblastomas driven by constitutive activation of sonic hedgehog (SHH) signaling. Patients with SHH-driven medulloblastomas with elevated expression of the RE1 silencing transcription factor (REST) and reduced expression of USP37 have poor outcomes. In previous studies, we showed sustained proliferation of SHH-medulloblastoma cells due to blockade of terminal cell cycle exit and neuronal differentiation stemming from a failure in USP37-dependent stabilization of its target, the cyclin-dependent kinase inhibitor …