Oncology
Abstract
Protein arginine methyltransferase 5 (PRMT5) complexes with methylosome protein 50 (MEP50) play crucial roles in tumor progress. However, the regulatory mechanism of governing the PRMT5-MEP50 hetero-octameric complex remains unclear. Here, we demonstrate that C6orf223, to our knowledge an uncharacterized protein, facilitates PRMT5-MEP50 multiprotein complex assembling, thereby promoting colorectal cancer (CRC) growth and metastasis. C6orf223 forms dimers through disulfide bonds, with its N-terminal arginine-enriched region binding to the C-terminal negatively charged groove of PRMT5, thus stabilizing PRMT5-MEP50 multiprotein and enhancing PRMT5 methyltransferase activity. Consequently, PRMT5-mediated H4R3me2s substantially decreases the expression of the tumor suppressor GATA5, leading to the upregulation of multiple oncogenic target genes including WWTR1, FGFR1, and CLU. Targeting C6orf223 using siRNAs encapsulated in ferritin protein shells effectively suppresses CRC tumor growth and metastasis. Collectively, our findings characterize the role of C6orf223 in facilitating PRMT5-MEP50 hetero-octameric complex assembling and suggest that C6orf223 could serve as a potential therapeutic target for CRC.
Authors
Yufeng Qiao, Zhenzhen Wu, Peng Wang, Yiliang Jin, Furong Bai, Fei Zhang, Yunhe An, Meiying Xue, Han Feng, Yong Zhang, Yaxin Hou, Junfeng Du, Huiyun Cai, Guizhi Shi, Bing Zhou, Pu Gao, Jizhong Lou, Peng Zhang, Kelong Fan, Jinbo Liu, Pengcheng Bu
Abstract
Hypoxia in the tumor microenvironment promotes lymphatic metastasis, yet the role of cancer-associated fibroblasts (CAFs) in this process remains insufficiently elucidated in colorectal cancer (CRC). In this study, we developed a large language model–based cellular hypoxia–predicting classifier to identify hypoxic CAFs (HCAFs) at single-cell resolution. Our findings revealed that HCAFs enhance CRC lymphatic metastasis by secreting CLEC11A, a protein that binds to the LGR5 receptor on tumor cells, subsequently activating the WNT/β-catenin signaling pathway. This promotes epithelial-mesenchymal transition and lymphangiogenesis, facilitating the spread of tumor cells via the lymphatic system. Furthermore, we demonstrate that the hypoxia-induced transcription factor HIF1A regulates the conversion of normoxic CAFs to HCAFs, driving CLEC11A expression and promoting metastasis. In vivo and vitro experiments confirmed the pro-metastatic role of CLEC11A in CRC, with its inhibition reducing lymphatic metastasis. This effect was markedly reversed by targeting the LGR5 receptor on tumor cells or inhibiting the WNT/β-catenin pathway, further elucidating the underlying mechanisms of CLEC11A-driven metastasis. These findings underscore the potential of targeting the CLEC11A-LGR5 axis to prevent lymphatic dissemination in CRC. Our study highlights the role of HCAFs in CRC progression and reveals mechanisms of lymphatic metastasis for intervention.
Authors
Chuhan Zhang, Teng Pan, Yuyuan Zhang, Yushuai Wu, Anning Zuo, Shutong Liu, Yuhao Ba, Benyu Liu, Shuaixi Yang, Yukang Chen, Hui Xu, Peng Luo, Quan Cheng, Siyuan Weng, Long Liu, Xing Zhou, Jingyuan Ning, Xinwei Han, Jinhai Deng, Zaoqu Liu
Abstract
The effectiveness of RAS/MAPK inhibitors in treating metastatic KRAS-mutant NSCLC is often hindered by the development of resistance driven by disrupted negative feedback mechanisms led by phosphatases like PP2A. PP2A is frequently suppressed in lung cancer to maintain elevated RAS/MAPK activity. Despite its established role in regulating oncogenic signaling, targeting PP2A with RAS/MAPK to prevent resistance has not been previously demonstrated. In this study, we aimed to establish a treatment paradigm by combining a PP2A molecular glue with a RAS/MAPK inhibitor to restore PP2A activity and counteract resistance. We demonstrated that KRASG12C and MEK1/2 inhibitors disrupted PP2A carboxymethylation and destabilized critical heterotrimeric complexes. Furthermore, genetic disruption of PP2A carboxymethylation enhanced intrinsic resistance to MEK1/2 inhibition both in vitro and in vivo. We developed RPT04402, a PP2A molecular glue that selectively stabilizes PP2A-B56α heterotrimers. In both commercial cell lines and a patient-derived model, combining RPT04402 with a RAS/MAPK inhibitor slowed proliferation and enhanced apoptosis. In mouse xenografts, this combination induced tumor regressions, extended median survival, and delayed the onset of treatment resistance. These findings highlight that promoting PP2A stabilization and RAS/MAPK inhibition presents a promising therapeutic strategy to improve treatment outcomes and overcome resistance in metastatic KRAS-mutant NSCLC.
Authors
Brynne Raines, Stephanie Tseng-Rogenski, Amanda C. Dowdican, Irene Peris, Matthew Hinderman, Kaitlin P. Zawacki, Kelsey Barrie, Gabrielle Hodges Onishi, Alexander M. Dymond, Tahra K. Luther, Sydney Musser, Behirda Karaj Majchrowski, J. Chad Brenner, Aqila Ahmed, Derek J. Taylor, Caitlin M. O'Connor, Goutham Narla
Abstract
The immunosuppressive tumor microenvironment (TME) drives radioresistance, but the role of γδ T cells in regulating radiosensitivity remains incompletely understood. In this study, we found that γδ T cell infiltration in the TME substantially increased after radiotherapy and contributed to radioresistance. Depletion of γδ T cells enhanced radiosensitivity. Single-cell RNA sequencing revealed that γδ T cells in the post-radiotherapy TME were characterized by the expression of Zbtb16, Il23r, and Il17a, and served as the primary source of IL-17A. These γδ T cells promoted radioresistance by recruiting myeloid-derived suppressor cells and suppressing T cell activation. Mechanistically, radiotherapy-induced tumor cell-derived microparticles containing dsDNA activated the cGAS-STING/NF-κB signaling pathway in macrophages, upregulating the expression of the chemokine CCL20, which was critical for γδ T cell recruitment. Targeting γδ T cells and IL-17A enhanced radiosensitivity and improved the efficacy of radiotherapy combined with anti-PD-1 immunotherapy, providing potential therapeutic strategies to overcome radioresistance.
Authors
Yue Deng, Xixi Liu, Xiao Yang, Wenwen Wei, Jiacheng Wang, Zheng Yang, Yajie Sun, Yan Hu, Haibo Zhang, Yijun Wang, Zhanjie Zhang, Lu Wen, Fang Huang, Kunyu Yang, Chao Wan
Abstract
The intratumor microenvironment shapes the metastatic potential of cancer cells and their susceptibility to any immune response. Yet the nature of the signals within the microenvironment that control anti-cancer immunity and how they are regulated is poorly understood. Here, using melanoma as a model, we investigate the involvement in metastatic dissemination and the immune-modulatory microenvironment of Protein S-Acyl Transferases, as an underexplored class of potential therapeutic targets. We find that ZDHHC13, suppresses metastatic dissemination by palmitoylation of CTNND1, leading to stabilization of E-cadherin. Importantly, ZDHHC13 also reshapes the tumor immune microenvironment by suppressing lysophosphatidylcholine (LPC) synthesis in melanoma cells, leading to inhibition of M2-like tumor-associated macrophages that we show degrades E-cadherin via MMP12 expression. Consequently, ZDHHC13 activity suppresses tumor growth and metastasis in immunocompetent mice. Our study highlights the therapeutic potential of targeting the ZDHHC13-E-cadherin axis and its downstream metabolic and immune-modulatory mechanisms, offering additional strategies to inhibit melanoma progression and metastasis.
Authors
Hongjin Li, Jianke Lyu, Yu Sun, Chengqian Yin, Yuewen Li, Weiqiang Chen, Suan-Sin Foo, Xianfang Wu, Colin Goding, Shuyang Chen
Abstract
TMPRSS2:ERG gene fusion (T:E fusion) in prostate adenocarcinoma (PCa) puts ERG under androgen receptor (AR) regulated TMPRSS2 expression. T:E fusion is associated with PTEN loss, and is highly associated with decreased INPP4B expression, which together may compensate for ERG-mediated suppression of AKT signaling. We confirmed in PCa cells and a mouse PCa model that ERG suppresses IRS2 and AKT activation. In contrast, ERG downregulation did not increase INPP4B, suggesting its decrease is indirect and reflects selective pressure to suppress INPP4B function. Notably, INPP4B expression is decreased in PTEN-intact and PTEN-deficient T:E fusion tumors, suggesting selection for a nonredundant function. As ERG in T:E fusion tumors is AR regulated, we further assessed whether AR inhibition increases AKT activity in T:E fusion tumors. A T:E fusion positive PDX had increased AKT activity in vivo and response to AKT inhibition in vitro after androgen deprivation. Moreover, two clinical trials of neoadjuvant AR inhibition prior to radical prostatectomy showed greater increases in AKT activation in the T:E fusion positive versus negative tumors. These findings indicate that AKT activation may mitigate the efficacy of AR targeted therapy in T:E fusion PCa, and that these patients may most benefit from combination therapy targeting AR and AKT.
Authors
Fen Ma, Sen Chen, Luigi Cecchi, Betul Ersoy-Fazlioglu, Joshua W. Russo, Seiji Arai, Seifeldin Awad, Carla Calagua, Fang Xie, Larysa Poluben, Olga Voznesensky, Anson T. Ku, Fatima Karzai, Changmeng Cai, David J. Einstein, Huihui Ye, Xin Yuan, Alex Toker, Mary-Ellen Taplin, Adam G. Sowalsky, Steven P. Balk
Abstract
Chemotherapy resistance remains a formidable challenge to the treatment of high-grade serous ovarian cancer (HGSOC). The drug-tolerant cells may originate from a small population of inherently resistant cancer stem cells (CSCs) in primary tumors. In contrast, sufficient evidence suggests that drug tolerance can also be transiently acquired by nonstem cancer cells. Regardless of the route, key regulators of this plastic process are poorly understood. Here, we utilized multiomics, tumor microarrays, and epigenetic modulation to demonstrate that SOX9 is a key chemo-induced driver of chemoresistance in HGSOC. Epigenetic upregulation of SOX9 was sufficient to induce chemoresistance in multiple HGSOC lines. Moreover, this upregulation induced the formation of a stem-like subpopulation and significant chemoresistance in vivo. Mechanistically, SOX9 increased transcriptional divergence, reprogramming the transcriptional state of naive cells into a stem-like state. Supporting this, we identified a rare cluster of SOX9-expressing cells in primary tumors that were highly enriched for CSCs and chemoresistance-associated stress gene modules. Notably, single-cell analysis showed that chemo treatment results in rapid population-level induction of SOX9 that enriches for a stem-like transcriptional state. Altogether, these findings implicate SOX9 as a critical regulator of early steps of transcriptional reprogramming that lead to chemoresistance through a CSC-like state in HGSOC.
Authors
Alexander J. Duval, Fidan Seker-Polat, Magdalena Rogozinska, Meric Kinali, Ann E. Walts, Ozlem Neyisci, Yaqi Zhang, Zhonglin Li, Edward J. Tanner III, Allison E. Grubbs, Sandra Orsulic, Daniela Matei, Mazhar Adli
Abstract
BACKGROUND. A key objective in managing HPV-positive oropharyngeal squamous cell carcinoma (OPSCC) is reducing radiation therapy (RT) doses without compromising cure rates. A recent Phase 2/3 HN005 trial revealed that clinical factors alone are insufficient to guide safe RT dose de-escalation. Our prior research demonstrated that the Genomic Adjusted Radiation Dose (GARD) predicts RT benefit and may inform dose selection. We hypothesize that GARD can guide personalized RT de-escalation in HPV-positive OPSCC patients. METHODS. Gene expression profiles were analyzed in 191 HPV-positive OPSCC patients enrolled in an international, multi-institutional observational study (AJCC 8th edition stages I–III). Most patients received 70 Gy in 35 fractions or 69.96 Gy in 33 fractions (median dose: 70 Gy, range: 51.0–74.0 Gy). Overall survival (OS) was 94.1% at 36 months and 87.3% at 60 months. Cox proportional hazards models assessed association between GARD and OS, and time-dependent ROC analyses compared GARD with traditional clinical predictors. RESULTS. Despite uniform RT dosing, GARD showed wide heterogeneity ([15.4–71.7]). Higher GARD values were significantly associated with improved OS in univariate (HR = 0.941, P = 0.041) and multivariable analyses (HR = 0.943, P = 0.046), while T and N stage were not. GARD demonstrated superior predictive performance at 36 months (AUC = 78.26) versus clinical variables (AUC = 71.20). Two GARD-based RT de-escalation strategies were identified, offering potential survival benefits while reducing radiation exposure. CONCLUSIONS. GARD predicts overall survival and outperforms clinical variables, supporting its integration into the diagnostic workflow for personalized RT in HPV-positive OPSCC.
Authors
Emily Ho, Loris De Cecco, Steven A. Eschrich, Stefano Cavalieri, Geoffrey Sedor, Frank J. Hoebers, Ruud H. Brakenhoff, Kathrin Scheckenbach, Tito Poli, Kailin Yang, Jessica A. Scarborough, Shivani Nellore, Shauna R. Campbell, Neil M. Woody, Timothy A. Chan, Jacob Miller, Natalie L. Silver, Shlomo Koyfman, James E. Bates, Jimmy J. Caudell, Michael W. Kattan, Lisa Licitra, Javier F. Torres-Roca, Jacob G. Scott
Abstract
Activating mutations in PIK3CA, the gene encoding the catalytic p110-alpha subunit of PI3K, are some of the most frequent genomic alterations in breast cancer. Alpelisib, a small-molecule inhibitor that targets p110-alpha, is a recommended drug for patients with PIK3CA-mutant advanced breast cancer. However, clinical success for PI3K inhibitors has been limited by their narrow therapeutic window. The lipid phosphatase PTEN is a potent tumour suppressor and a major negative regulator of the PI3K pathway. Unsurprisingly, inactivating mutations in PTEN correlate with tumour progression and resistance to PI3K inhibition due to persistent PI3K signalling. Here we demonstrate that PI3K inhibition leads rapidly to the inactivation of PTEN. Using a functional genetic screen we show that this effect is mediated by a USP10-GSK3-B signalling axis, in which USP10 stabilizes GSK3-B resulting in GSK3-B-mediated phosphorylation of the C-terminal tail of PTEN. This phosphorylation inhibits PTEN dimerization and thus prevents its activation. Downregulation of GSK3-B or USP10 re-sensitizes PI3K inhibitor resistant breast cancer models and patient derived organoids to PI3K inhibition and induces tumour regression. Our study establishes that enhancing PTEN activity is a new strategy to treat PIK3CA mutant tumours and provides a strong rationale for pursuing USP10 inhibitors in the clinic.
Authors
Nishi Kumari, Sarah CE. Wright, Christopher M. Witham, Laia Monserrat, Marta Palafox, John Lalith Charles Richard, Carlotta Costa, Moshe Elkabets, Mark Agostino, Theresa Klemm, Melissa K. Eccles, Alexandra Garnham, Ting Wu, Jonas A. Nilsson, Nikita Walz, Veena Venugopal, Anthony Cerra, Natali Vasilevski, Stephanie C. Bridgeman, Sona Bassi, Azad Saei, Moutaz Helal, Philipp Neundorf, Angela Riedel, Mathias Rosenfeldt, Jespal Gill, Nikolett Pahor, Oliver Hartmann, Jacky Chung, Sachdev S. Sidhu, Nina Moderau, Sudhakar Jha, Jordi Rodon, Markus E. Diefenbacher, David Komander, Violeta Serra, Pieter Eichhorn
Abstract
3-O-sulfation of heparan sulfate (HS) is the key determinant for binding and activation of Antithrombin III (AT). This interaction is the basis of heparin treatment to prevent thrombotic events and excess coagulation. Antithrombin-binding HS (HSAT) is expressed in human tissues, but is thought to be expressed in the subendothelial space, mast cells, and follicular fluid. Here we show that HSAT is ubiquitously expressed in the basement membranes of epithelial cells in multiple tissues. In the pancreas, HSAT is expressed by healthy ductal cells and its expression is increased in premalignant pancreatic intraepithelial neoplasia lesions (PanINs), but not in pancreatic ductal adenocarcinoma (PDAC). Inactivation of HS3ST1, a key enzyme in HSAT synthesis, in PDAC cells eliminated HSAT expression, induced an inflammatory phenotype, suppressed markers of apoptosis, and increased metastasis in an experimental mouse PDAC model. HSAT-positive PDAC cells bind AT, which inhibits the generation of active thrombin by tissue factor (TF) and Factor VIIa. Furthermore, plasma from PDAC patients showed accumulation of HSAT suggesting its potential as a marker of tumor formation. These findings suggest that HSAT exerts a tumor suppressing function through recruitment of AT and that the decrease in HSAT during progression of pancreatic tumorigenesis increases inflammation and metastatic potential.
Authors
Thomas Mandel Clausen, Ryan J. Weiss, Jacob R. Tremblay, Benjamin P. Kellman, Joanna Coker, Leo A. Dworkin, Jessica P. Rodriguez, Ivy M. Chang, Timothy Chen, Vikram Padala, Richard Karlsson, Hyemin Song, Kristina L. Peck, Satoshi Ogawa, Daniel R. Sandoval, Hiren J. Joshi, Gaowei Wang, L. Paige Ferguson, Nikita Bhalerao, Allison Moores, Tannishtha Reya, Maike Sander, Thomas C. Caffrey, Jean L. Grem, Alexandra Aicher, Christopher Heeschen, Dzung Le, Nathan E. Lewis, Michael A. Hollingsworth, Paul M. Grandgenett, Susan L. Bellis, Rebecca L. Miller, Mark M. Fuster, David W. Dawson, Dannielle D. Engle, Jeffrey D. Esko
Copyright © 2025 American Society for Clinical Investigation
ISSN: 0021-9738 (print), 1558-8238 (online)