Ubiquitination plays an essential role in protein stability, subcellular localization, and interactions. Crosstalk between different types of ubiquitination results in distinct biological outcomes for proteins. However, the role of ubiquitination-related crosstalk in lymph node (LN) metastasis and the key regulatory factors controlling this process have not been determined. Using high-throughput sequencing, we found that ubiquitin-conjugating enzyme E2 C (UBE2C) was overexpressed in bladder cancer (BCa) and was strongly associated with an unfavorable prognosis. Overexpression of UBE2C increased BCa lymphangiogenesis and promoted LN metastasis both in vitro and in vivo. Mechanistically, UBE2C mediated sodium-coupled neutral amino acid transporter 2 (SNAT2) monoubiquitination at lysine 59 to inhibit K63-linked polyubiquitination at lysine 33 of SNAT2. Crosstalk between monoubiquitination and K63-linked polyubiquitination increased SNAT2 membrane protein levels by suppressing epsin 1–mediated (EPN1-mediated) endocytosis. SNAT2 facilitated glutamine uptake and metabolism to promote VEGFC secretion, ultimately leading to lymphangiogenesis and LN metastasis in patients with BCa. Importantly, inhibition of UBE2C significantly attenuated BCa lymphangiogenesis in a patient-derived xenograft model. Our results reveal the mechanism by which UBE2C mediates crosstalk between the monoubiquitination and K63-linked polyubiquitination of SNAT2 to promote BCa metastasis and identify UBE2C as a promising target for treating LN-metastatic BCa.
Wenjie Li, Changhao Chen, Hanhao Zheng, Yan Lin, Mingjie An, Daiyin Liu, Yonghai Zhang, Mingchao Gao, Tianhang Lan, Wang He
BACKGROUND. Obesity is the foremost risk factor in the development of endometrial cancer (EC). However, the impact of obesity on the response to immune checkpoint inhibitors (ICI) in EC remains poorly understood. This retrospective study investigates the association between body mass index (BMI), body fat distribution, and clinical and molecular characteristics of EC patients treated with ICI. METHODS. We analyzed progression-free survival (PFS) and overall survival (OS) in EC patients treated with ICI, categorized by BMI, fat mass distribution, and molecular subtypes. Incidence of immune-related adverse events (irAE) after ICI was also assessed based on BMI status. RESULTS. 524 EC patients were included in the study. Overweight and obese patients exhibited a significantly prolonged PFS and OS compared to normal BMI patients after treatment with ICI. Multivariable Cox regression analysis confirmed the independent association of overweight and obesity with improved PFS and OS. Elevated visceral adipose tissue (VAT) was identified as a strong independent predictor for improved PFS to ICI. Associations between obesity and OS/PFS were particularly significant in the copy number-high/TP53abnormal (CN-H/TP53abn) EC molecular subtype. Finally, obese patients demonstrated a higher irAE rate compared to normal BMI individuals. CONCLUSION. Obesity is associated with improved outcomes to ICI in EC patients and a higher rate of irAEs. This association is more pronounced in the CN-H/TP53abn EC molecular subtype. FUNDING. NIH/NCI Cancer Center Support Grant P30CA008748 (MSK). K08CA266740 and MSK Gerstner Physician Scholars Program (J.C.O). RUCCTS Grant #UL1 TR001866 (N.G-B and C.S.J). Cycle for survival and Breast Cancer Research Foundation grants (B.W).
Nicolás Gómez-Banoy, Eduardo J. Ortiz, Caroline S. Jiang, Christian Dagher, Carlo Sevilla, Jeffrey Girshman, Andrew M. Pagano, Andrew J. Plodkowski, William A. Zammarrelli, Jennifer J. Mueller, Carol Aghajanian, Britta Weigelt, Vicky Makker, Paul Cohen, Juan C. Osorio
STING agonists can reprogram the tumor microenvironment to induce immunological clearance within the central nervous system. Using multiplexed sequential immunofluorescence (SeqIF) and the Ivy Glioblastoma Atlas, STING expression was found in myeloid populations and in the perivascular space. The STING agonist 8803 increased median survival in multiple preclinical models of glioblastoma, including QPP8, an immune checkpoint blockade–resistant model, where 100% of mice were cured. Ex vivo flow cytometry profiling during the therapeutic window demonstrated increases in myeloid tumor trafficking and activation, alongside enhancement of CD8+ T cell and NK effector responses. Treatment with 8803 reprogrammed microglia to express costimulatory CD80/CD86 and iNOS, while decreasing immunosuppressive CD206 and arginase. In humanized mice, where tumor cell STING is epigenetically silenced, 8803 therapeutic activity was maintained, further attesting to myeloid dependency and reprogramming. Although the combination with a STAT3 inhibitor did not further enhance STING agonist activity, the addition of anti–PD-1 antibodies to 8803 treatment enhanced survival in an immune checkpoint blockade–responsive glioma model. In summary, 8803 as a monotherapy demonstrates marked in vivo therapeutic activity, meriting consideration for clinical translation.
Hinda Najem, Spencer T. Lea, Shashwat Tripathi, Lisa Hurley, Chao-Hsien Chen, Ivana William, Moloud Sooreshjani, Michelle Bowie, Genevieve Hartley, Corey Dussold, Sebastian Pacheco, Crismita Dmello, Catalina Lee-Chang, Kathleen McCortney, Alicia Steffens, Jordain Walshon, Martina Ott, Jun Wei, Anantha Marisetty, Irina Balyasnikova, Roger Stupp, Rimas V. Lukas, Jian Hu, Charles David James, Craig M. Horbinski, Maciej S. Lesniak, David M. Ashley, Waldemar Priebe, Leonidas C. Platanias, Michael A. Curran, Amy B. Heimberger
Most children with medulloblastoma (MB) achieve remission, but some face very aggressive metastatic tumors. Their dismal outcome highlights the critical need to advance therapeutic approaches that benefit such high-risk patients. Minnelide, a clinically relevant analog of the natural product triptolide, has oncostatic activity in both preclinical and early clinical settings. Despite its efficacy and tolerable toxicity, this compound has not been evaluated in MB. Utilizing a bioinformatic dataset that integrates cellular drug response data with gene expression, we predicted that Group 3 (G3) MB, which has a poor five-year survival, would be sensitive to triptolide/Minnelide. We subsequently showed that both triptolide and Minnelide attenuate the viability of G3 MB cells ex vivo. Transcriptomic analyses identified MYC signaling, a pathologically relevant driver of G3 MB, as a downstream target of this class of drugs. We validated this MYC dependency in G3 MB cells and showed that triptolide exerts its efficacy by reducing both MYC transcription and MYC protein stability. Importantly, Minnelide acted on MYC to reduce tumor growth and leptomeningeal spread, which resulted in improved survival of G3 MB animal models. Moreover, Minnelide improved the efficacy of adjuvant chemotherapy, further highlighting its potential for the treatment of MYC-driven G3 MB patients.
Jezabel Rodriguez-Blanco, April D. Salvador, Robert K. Suter, Marzena Swiderska-Syn, Isabel Palomo-Caturla, Valentin Kliebe, Pritika Shahani, Kendell Peterson, Maria Turos-Cabal, Megan E. Vieira, Daniel T. Wynn, Ashley J. Howell, Fan Yang, Yuguang Ban, Heather J. McCrea, Frederique Zindy, Etienne Danis, Rajeev Vibhakar, Anna Jermakowicz, Vanesa Martin, Christopher C. Coss, Brent T. Harris, Aguirre de Cubas, X. Steven Chen, Thibaut Barnoud, Martine F. Roussel, Nagi G. Ayad, David J. Robbins
Aberrant activation of RAS-MAPK signaling is common in cancer, and efforts to inhibit pathway components have yielded drugs with promising clinical activities. Unfortunately, treatment-provoked adaptive resistance mechanisms inevitably develop, limiting their therapeutic potential. As a central node essential for receptor tyrosine kinase mediated RAS activation, SHP2 has emerged as an attractive cancer target. Consequently, many SHP2 allosteric inhibitors are now in clinical testing. Here we discovered a previously unrecognized off-target effect associated with SHP2 allosteric inhibitors. We found that these inhibitors accumulate in the lysosome and block autophagic flux in a SHP2-independent manner. We showed that off-target autophagy inhibition by SHP2 allosteric inhibitors contributes to their anti-tumor activity. We also demonstrated that SHP2 allosteric inhibitors harboring this off-target activity not only suppress oncogenic RAS signaling but also overcome drug resistance such as MAPK rebound and protective autophagy in response to RAS-MAPK pathway blockage. Finally, we exemplified a therapeutic framework that harnesses both the on- and off-target activities of SHP2 allosteric inhibitors for improved treatment of mutant RAS driven and drug resistant malignancies such as pancreatic and colorectal cancers. Brief Summary: SHP2 allosteric inhibitors elicit off-target autophagy blockade that can be exploited for improved treatment of RAS-driven and drug-resistant cancers.
Yiming Miao, Yunpeng Bai, Jinmin Miao, Allison A. Murray, Jianping Lin, Jiajun Dong, Zihan Qu, Ruo-Yu Zhang, Quyen D. Nguyen, Shaomeng Wang, Jingmei Yu, Frederick Nguele Meke, Zhong-Yin Zhang
BACKGROUND. Clinical trials have suggested antitumor activity from PARP inhibition beyond homologous recombination deficiency (HRD). RNASEH2B loss is unrelated to HRD and preclinically sensitizes to PARP inhibition. The current study reports on RNASEH2B protein loss in advanced prostate cancer and its association with RB1 protein loss, clinical outcome and clonal dynamics during treatment with PARP inhibition in a prospective clinical trial. METHODS. Whole tumor biopsies from multiple cohorts of patients with advanced prostate cancer were interrogated using whole-exome sequencing (WES), RNA sequencing (bulk and single nucleus) and immunohistochemistry (IHC) for RNASEH2B and RB1. Biopsies from patients treated with olaparib in the TOPARP-A and TOPARP-B clinical trials were used to evaluate RNASEH2B clonal selection during olaparib treatment. RESULTS. Shallow co-deletion of RNASEH2B and adjacent RB1, co-located at chromosome 13q14, was common, deep co-deletion infrequent, and gene loss associated with lower mRNA expression. In castration-resistant PC (CRPC) biopsies, RNASEH2B and RB1 mRNA expression correlated, but single nucleus RNA sequencing indicated discordant loss of expression. IHC studies showed that loss of the two proteins often occurred independently, arguably due to stochastic second allele loss. Pre- and post-treatment metastatic CRPC (mCRPC) biopsy studies from BRCA1/2 wildtype tumors, treated on the TOPARP phase II trial, indicated that olaparib eradicates RNASEH2B-loss tumor subclones. CONCLUSION. PARP inhibition may benefit men suffering from mCRPC by eradicating tumor subclones with RNASEH2B loss. TRIAL REGISTRATION. Clinicaltrials.gov NCT01682772 FUNDING. AstraZeneca; Cancer Research UK; Medical Research Council; Cancer Research UK; Prostate Cancer UK; Movember Foundation; Prostate Cancer Foundation.
Juliet Carmichael, Ines Figueiredo, Bora Gurel, Nick Beije, Wei Yuan, Jan Rekowski, George Seed, Suzanne Carreira, Claudia Bertan, Maria de Los Dolores Fenor de la Maza, Khobe Chandran, Antje Neeb, Jon Welti, Lewis Gallagher, Denisa Bogdan, Mateus Crespo, Ruth Riisnaes, Ana Ferreira, Susana Miranda, Jinqiu Lu, Michael M. Shen, Emma Hall, Nuria Porta, Daniel Westaby, Christina Guo, Rafael Grochot, Christopher J. Lord, Joaquin Mateo, Adam Sharp, Johann de Bono
Intratumoral regulatory T cells (Tregs) are key mediators of cancer immunotherapy resistance, including anti-PD-(L)1 immune checkpoint blockade (ICB). The mechanisms driving Treg infiltration into the tumor microenvironment (TME) and the consequence on CD8+ T cell exhaustion remains elusive. Herein, we report that heat shock protein gp96 (GRP94) is indispensable for Treg tumor infiltration, primarily through gp96’s roles in chaperoning integrins. Among various gp96-dependent integrins, we found that only LFA-1 (αL integrin) but not αV, CD103 (αE) or β7 integrin was required for Treg tumor homing. Loss of Treg infiltration into the TME by genetically deleting gp96/LFA-1 potently induces rejection of multiple ICB-resistant murine cancer models in a CD8+ T cell-dependent manner without loss of self-tolerance. Moreover, gp96 deletion impeded Treg activation primarily by suppressing IL-2/STAT5 signaling, which also contributes to tumor regression. By competing for intratumoral IL-2, Tregs prevent activation of CD8+ tumor-infiltrating lymphocytes (TILs), drive TOX induction and induce bona fide CD8+ T cell exhaustion. By contrast, Treg ablation leads to striking CD8+ T cell activation without TOX induction, demonstrating clear uncoupling of the two processes. Our study reveals that the gp96/LFA-1 axis plays a fundamental role in Treg biology and suggests that Treg-specific gp96/LFA-1 targeting represents a valuable strategy for cancer immunotherapy without inflicting autoinflammatory conditions.
Lei Zhou, Maria Velegraki, Yi Wang, J K Mandula, Yuzhou Chang, Weiwei Liu, No-Joon Song, Hyunwoo Kwon, Tong Xiao, Chelsea Bolyard, Feng Hong, Gang Xin, Qin Ma, Mark P. Rubinstein, Haitao Wen, Zihai Li
PTEN inactivation is prevalent in human prostate cancer and causes high-grade adenocarcinoma with a long latency. Cancer associated fibroblasts (CAFs) play a pivotal role in tumor progression, but it remains elusive whether and how PTEN-deficient prostate cancers reprogram CAFs to overcome the barriers for tumor progression. Herein, we report that PTEN deficiency induces KLF5 acetylation; and interruption of KLF5 acetylation orchestrates intricate interactions between cancer cells and CAFs that enhance FGFR1 signaling and promote tumor growth. Deacetylated KLF5 promotes tumor cells to secrete TNF-α, which stimulates inflammatory CAFs to release FGF9. CX3CR1 inhibition blocks FGFR1 activation triggered by FGF9 and sensitizes PTEN-deficient prostate cancer to AKT inhibitor capivasertib. This study reveals the role of KLF5 acetylation in reprogramming CAFs and provides a rational for combined therapies using inhibitors of AKT and CX3CR1.
Baotong Zhang, Mingcheng Liu, Fengyi Mai, Xiawei Li, Wenzhou Wang, Qingqing Huang, Xiancai Du, Weijian Ding, Yixiang Li, Benjamin Barwick, Jianping Ni, Adeboye Osunkoya, Yuanli Chen, Wei Zhou, Siyuan Xia, Jin-Tang Dong
Diffuse midline glioma (DMG) H3K27-altered is one of the devastating childhood cancers. Radiation therapy remains the only effective treatment yet provides a 5-year survival rate of only 1%. Several clinical trials have attempted to enhance radiation anti-tumor activity using radiosensitizing agents, although none have been successful. Given this, there is a critical need for identifying effective therapeutics to enhance radiation sensitivity for the treatment of DMG. Using high-throughput radiosensitivity screening, we identified bromo- and extra-terminal domain (BET) protein inhibitors as potent radiosensitizers in DMG cells. Genetic and pharmacologic inhibition of BET bromodomain activity reduced DMG cell proliferation and enhanced radiation-induced DNA damage by inhibiting DNA repair pathways. RNA-seq and CUT & RUN showed that BET bromodomain inhibitors regulate the expression of DNA repair genes mediated by H3K27 acetylation at enhancers. BET bromodomain inhibitors enhanced DMG radiation-response in patient-derived xenografts as well as genetically engineered mouse models. Together, our results highlight BET bromodomain inhibitors as radiosensitizer and provide a rationale for developing combination therapy with radiation for the treatment of DMG.
Jun Watanabe, Matthew R. Clutter, Michael J. Gullette, Takahiro Sasaki, Eita Uchida, Savneet Kaur, Yan Mo, Kouki Abe, Yukitomo Ishi, Nozomu Takata, Manabu Natsumeda, Samantha Gadd, Zhiguo Zhang, Oren J. Becher, Rintaro Hashizume
The diversity of structural variants (SVs) in melanoma and how they impact oncogenesis are incompletely known. We performed harmonized analysis of SVs across melanoma histological and genomic subtypes, and we identified distinct global properties between subtypes. These included the frequency and size of SVs and SV classes, their relation to chromothripsis events, and the role of topologically associated domain (TAD) boundary altering SVs on cancer-related genes. Following our prior identification of double-stranded break repair deficiency in a subset of triple wild-type cutaneous melanoma, we identified MRE11 and NBN loss-of-function SVs in melanomas with this mutational signature. Experimental knockouts of MRE11 and NBN, followed by olaparib cell viability assays in melanoma cells, indicated that dysregulation of each of these genes may cause sensitivity to PARPi in cutaneous melanomas. Broadly, harmonized analysis of melanoma SVs revealed distinct global genomic properties and molecular drivers, which may have biological and therapeutic impact.
Jake R. Conway, Riaz Gillani, Jett Crowdis, Brendan Reardon, Jihye Park, Seung Hun Han, Breanna M. Titchen, Mouadh Benamar, Rizwan Haq, Eliezer M. Van Allen