Oncologies
Abstract
Gastric cancer often shows malignant growth and insensitivity to chemotherapeutic drugs due to the regulation of complex molecular mechanisms, which results in poor prognosis for patients. However, the relevant molecular mechanisms remain unclear. In this study, we reported that family with sequence similarity 117, member B (FAM117B), promoted the growth of gastric cancer cells and reduced the sensitivity of cells to chemotherapeutic drugs. Mechanistically, FAM117B competed with nuclear factor E2–related factor 2 (NRF2) for Kelch-like ECH-associated protein 1 (KEAP1) binding, reduced the ubiquitination degradation of NRF2, and activated the KEAP1/NRF2 signaling pathway. Moreover, FAM117B-induced growth and chemoresistance of gastric cancer cells were NRF2 dependent. We found that FAM117B and NRF2 protein levels were highly expressed in tumor tissues of patients with gastric cancer and their co-overexpression represented an independent factor for poor prognosis. Collectively, our findings reveal that FAM117B is involved in promoting gastric cancer growth and drug resistance, and it could be exploited as a cancer therapeutic target.
Authors
Yunjiang Zhou, Yaxin Chen, Yongwei Shi, Leyin Wu, Yingying Tan, Tao Li, Yigang Chen, Jiazeng Xia, Rong Hu
Abstract
Programmed death-ligand 1 (PD-L1), a critical immune checkpoint ligand, is a transmembrane protein synthesized in the endoplasmic reticulum of tumor cells and transported to the plasma membrane to interact with programmed death 1 (PD-1) expressed on T cell surface. This interaction delivers coinhibitory signals to T cells, thereby suppressing their function and allowing evasion of antitumor immunity. Most companion or complementary diagnostic devices for assessing PD-L1 expression levels in tumor cells used in the clinic or in clinical trials require membranous staining. However, the mechanism driving PD-L1 translocation to the plasma membrane after de novo synthesis is poorly understood. Herein, we showed that mind bomb homolog 2 (MIB2) is required for PD-L1 transportation from the trans-Golgi network (TGN) to the plasma membrane of cancer cells. MIB2 deficiency led to fewer PD-L1 proteins on the tumor cell surface and promoted antitumor immunity in mice. Mechanistically, MIB2 catalyzed nonproteolytic K63-linked ubiquitination of PD-L1, facilitating PD-L1 trafficking through Ras-associated binding 8–mediated (RAB8-mediated) exocytosis from the TGN to the plasma membrane, where it bound PD-1 extrinsically to prevent tumor cell killing by T cells. Our findings demonstrate that nonproteolytic ubiquitination of PD-L1 by MIB2 is required for its transportation to the plasma membrane and tumor cell immune evasion.
Authors
Xinfang Yu, Wei Li, Haidan Liu, Xu Wang, Cristian Coarfa, Chao Cheng, Xinlian Yu, Zhaoyang Zeng, Ya Cao, Ken H. Young, Yong Li
Abstract
BACKGROUND. Relatlimab+nivolumab (anti-LAG3+anti-PD1) has been approved by FDA as a 1st-line therapy in stage III/IV melanoma, but its detailed effect on the immune system is unknown. METHODS. We evaluated blood samples from 40 immunotherapy-naïve or prior immunotherapy-refractory patients with metastatic melanoma treated with anti-LAG3+anti-PD1 in a phase I trial (NCT01968109) using single-cell RNA and T cell receptor (TCR) sequencing (scRNA+TCRαβ-seq) combined with other multiomics profiling. RESULTS. The highest LAG3 expression was noted in NK cells, regulatory T cells (Tregs), and CD8+ T cells, and these cell populations underwent the most significant changes during the treatment. Adaptive NK cells were enriched in responders and underwent profound transcriptomic changes during the therapy resulting in an active phenotype. LAG3+ Tregs expanded but based on the transcriptome profile became metabolically silent during the treatment. Lastly, higher baseline TCR clonality was observed in responding patients, and their expanding CD8+ T cell clones gained more cytotoxic and NK-like phenotype. CONCLUSION. Anti-LAG3+anti-PD1 therapy has profound effects on NK cells and Tregs in addition to CD8+ T cells. TRIAL REGISTRATION. ClinicalTrials.gov (NCT01968109) FUNDING. Cancer Foundation Finland, Sigrid Juselius Foundation, Signe and Ane Gyllenberg Foundation, Relander Foundation, State funding for university-level health research in Finland, a Helsinki Institute of Life Sciences Fellow grant, Academy of Finland, and an investigator-initiated research grant from BMS.
Authors
Jani Huuhtanen, Henna H.E. Kasanen, Katriina Peltola, Tapio Lönnberg, Virpi Glumoff, Oscar Brück, Olli Dufva, Karita Peltonen, Johanna Vikkula, Emmi Jokinen, Mette Ilander, Moon Hee Lee, Siru Mäkelä, Marta Nyakas, Bin Li, Micaela Hernberg, Petri Bono, Harri Lähdesmäki, Anna Kreutzman, Satu Mustjoki
Abstract
Myeloproliferative neoplasms (MPNs) are characterized by the activated JAK2-STAT pathway. Pleckstrin-2 (Plek2) is a downstream target of the JAK2-STAT pathway and overexpressed in patients with MPNs. We previously revealed that Plek2 plays critical roles in the pathogenesis of JAK2 mutated MPNs. The non-essential roles of Plek2 under physiologic conditions makes it an ideal target for MPN therapy. Here we identified first-in-class Plek2 inhibitors through an in silico high-throughput screening and cell-based assays followed by the synthesis of analogs. The Plek2 specific small molecule inhibitors showed potent inhibitory effects on cell proliferation. Mechanistically, Plek2 interacts with and enhances the activity of Akt through the recruitment of downstream effector proteins. The Plek2 signaling complex also includes Hsp72 that protects Akt from degradation. These functions were blocked by Plek2 inhibitors via their direct binding to Plek2 DEP domain. The role of Plek2 in activating the Akt signaling was further confirmed in vivo using a hematopoietic specific Pten knockout mouse model. We next tested Plek2 inhibitors alone or in combination with an Akt inhibitor in various MPN mouse models, which showed significant therapeutic efficacies similar to the genetic depletion of Plek2. The Plek2 inhibitor was also effective in reducing proliferation of CD34 positive cells from MPN patients. Our studies reveal a Plek2-Akt complex that drives cell proliferation and can be targeted by a new class of anti-proliferative compounds for MPN therapy.
Authors
Xu Han, Yang Mei, Rama K. Mishra, Honghao Bi, Atul D. Jain, Gary E. Schiltz, Baobing Zhao, Madina Sukhanova, Pan Wang, Arabela A. Grigorescu, Patricia C. Weber, John J. Piwinski, Miguel A. Prado, Joao A. Paulo, Len Stephens, Karen E. Anderson, Charles S. Abrams, Jing Yang, Peng Ji
Abstract
Prostate cancer is highly dependent on androgens and the androgen receptor (AR). Hormonal therapies inhibit gonadal testosterone production, block extragonadal androgen biosynthesis, or directly antagonize AR. Resistance to medical castration occurs as castration-resistant prostate cancer (CRPC) and is driven by reactivation of the androgen-AR axis. 3β-hydroxysteroid dehydrogenase-1 (3βHSD1) serves as the rate-limiting step for potent androgen synthesis from extragonadal precursors, thereby stimulating CRPC. Genetic evidence in men demonstrates the role of 3βHSD1 in driving CRPC. In postmenopausal women, 3βHSD1 is required for synthesis of aromatase substrates and plays an essential role in breast cancer. Therefore, 3βHSD1 lies at a critical junction for the synthesis of androgens and estrogens, and this metabolic flux is regulated through germline-inherited mechanisms. We show that phosphorylation of tyrosine 344 (Y344) occurs and is required for 3βHSD1 cellular activity and generation of Δ4, 3-keto-substrates of 5α-reductase and aromatase, including in patient tissues. BMX directly interacts with 3βHSD1 and is necessary for enzyme phosphorylation and androgen biosynthesis. In vivo blockade of 3βHSD1 Y344 phosphorylation inhibits CRPC. These findings identify what we believe to be new hormonal therapy pharmacologic vulnerabilities for sex-steroid dependent cancers.
Authors
Xiuxiu Li, Michael Berk, Christopher Goins, Mohammad Alyamani, Yoon-Mi Chung, Chenyao Wang, Monaben Patel, Nityam Rathi, Ziqi Zhu, Belinda Willard, Shaun Stauffer, Eric Klein, Nima Sharifi
Abstract
Tyrosine kinase inhibitors (TKIs) targeting epidermal growth factor receptor (EGFR) are effective for many patients with lung cancer with EGFR mutations. However, not all patients are responsive to EGFR TKIs, including even those harboring EGFR-sensitizing mutations. In this study, we quantified the cells and cellular interaction features of the tumor microenvironment (TME) using routine H&E-stained biopsy sections. These TME features were used to develop a prediction model for survival benefit from EGFR TKI therapy in patients with lung adenocarcinoma and EGFR-sensitizing mutations in the Lung Cancer Mutation Consortium 1 (LCMC1) and validated in an independent LCMC2 cohort. In the validation data set, EGFR TKI treatment prolonged survival in the predicted-to-benefit group but not in the predicted-not-to-benefit group. Among patients treated with EGFR TKIs, the predicted-to-benefit group had prolonged survival outcomes compared with the predicted not-to-benefit group. The EGFR TKI survival benefit positively correlated with tumor-tumor interaction image features and negatively correlated with tumor-stroma interaction. Moreover, the tumor-stroma interaction was associated with higher activation of the hepatocyte growth factor/MET-mediated PI3K/AKT signaling pathway and epithelial-mesenchymal transition process, supporting the hypothesis of fibroblast-involved resistance to EGFR TKI treatment.
Authors
Shidan Wang, Ruichen Rong, Donghan M. Yang, Junya Fujimoto, Justin A. Bishop, Shirley Yan, Ling Cai, Carmen Behrens, Lynne D. Berry, Clare Wilhelm, Dara Aisner, Lynette Sholl, Bruce E. Johnson, David J. Kwiatkowski, Ignacio I. Wistuba, Paul A. Bunn Jr., John Minna, Guanghua Xiao, Mark G. Kris, Yang Xie
Abstract
The role of tumor-associated macrophages (TAMs) along with the regulatory mechanisms underlying distinct macrophage activation states remain poorly understood in prostate cancer (PCa). Herein, we reported that PCa growth in macrophage-specific Ubc9 deficient mice is substantially suppressed compared to their wild-type littermates, an effect partially ascribed to the augmented CD8+ T cell response. Biochemical and molecular analyses revealed that the signal transducer and activator of transcription 4 (STAT4) is a crucial UBC9-mediated SUMOylation target, with lysine residue 350 (K350) as the major modification site. Site-directed mutation of STAT4 (K350R) enhanced its nuclear translocation and stability, thereby facilitating the proinflammatory activation of macrophages. Importantly, administration of UBC9 inhibitor, 2-D08, promoted the antitumor effect of TAMs and increased the expression of PD-1 on CD8+ T cells, supporting a synergistic antitumor efficacy once it combined with the immune checkpoint blockade (ICB) therapy. Together, our results demonstrated that ablation of UBC9 could reverse the immunosuppressive phenotype of TAMs via promoting STAT4 mediated macrophage activation and macrophage-CD8+ T cell crosstalk, which provides valuable insights to halt the pathogenic process of tumorigenesis.
Authors
Jun Xiao, Fei Sun, Ya-Nan Wang, Bo Liu, Peng Zhou, Fa-Xi Wang, Hai-Feng Zhou, Yue Ge, Tian-Tian Yue, Jia-Hui Luo, Chun-Liang Yang, Shan-Jie Rong, Ze-Zhong Xiong, Sheng Ma, Qi Zhang, Yang Xun, Chun-Guang Yang, Yang Luan, Shao-Gang Wang, Cong-Yi Wang, Zhi-Hua Wang
Abstract
Ubiquitin-conjugating enzyme E2C (UBE2C) mediates the ubiquitylation chain formation via the K11 linkage. While previous in vitro studies showed that UBE2C plays a growth-promoting role in cancer cell lines, the underlying mechanism remains elusive. Still unknown is whether and how UBE2C plays a promoting role in vivo. Here we reported that UBE2C is indeed essential for growth and survival of lung cancer cells harboring Kras mutations, and UBE2C is required for KrasG12D-induced lung tumorigenesis, since Ube2c deletion significantly inhibits tumor formation and extends the life-span of mice. Mechanistically, KrasG12D induces expression of UBE2C, which couples with APC/CCDH1 E3 ligase to promote ubiquitylation and degradation of DEPTOR, leading to activation of the mTORC signals. Importantly, DEPTOR levels are fluctuated during cell cycle progression in a manner dependent of UBE2C and CDH1, indicating their physiological connection. Finally, Deptor deletion fully rescues the tumor inhibitory effect of Ube2c deletion in the KrasG12D lung tumor model, indicating a causal role of Deptor. Taken together, our study shows that the UBE2C/CDH1/DEPTOR axis forms an oncogene-tumor suppressor cascade that regulates cell cycle progression and autophagy and validates that UBE2C is an attractive target for lung cancer associated with Kras mutations.
Authors
Shizhen Zhang, Xiahong You, Yawen Zheng, Yanwen Shen, Xiufang Xiong, Yi Sun
Abstract
Autologous stem cell transplantation (ASCT), with subsequent lenalidomide maintenance is standard consolidation therapy for multiple myeloma and a subset of patients achieve durable progression-free survival that is suggestive of long-term immune control. Nonetheless, most patients ultimately relapse, suggesting immune escape. TIGIT appears a potent inhibitor of myeloma-specific immunity and represents a promising checkpoint target. Here we demonstrate high expression of TIGIT on activated CD8 T cells in mobilized peripheral blood stem cell grafts from patients with myeloma. To guide clinical application of TIGIT inhibition, we evaluated identical TIGIT Abs that do or do not engage FcγR and demonstrated that anti-TIGIT activity is dependent on FcγR binding. We subsequently used CRBN mice to investigate the efficacy of anti-TIGIT in combination with lenalidomide maintenance after transplantation. Notably, the combination of anti-TIGIT with lenalidomide provided synergistic, CD8 T cell-dependent, anti-myeloma efficacy. Analysis of bone marrow (BM) CD8 T cells demonstrated that combination therapy suppressed T cell exhaustion, enhanced effector function, and expanded central memory subsets. Importantly, these immune phenotypes were specific to the BM tumor microenvironment. Collectively, these data provide a logical rationale for combining TIGIT inhibition with immunomodulatory drugs to prevent myeloma progression after stem cell transplantation.
Authors
Simone A. Minnie, Olivia G. Waltner, Kathleen S. Ensbey, Stuart D. Olver, Alika D. Collinge, David P. Sester, Christine R. Schmidt, Samuel R.W. Legg, Shuichiro Takahashi, Nicole S. Nemychenkov, Tomoko Sekiguchi, Gregory Driessens, Ping Zhang, Motoko Koyama, Andrew Spencer, Leona A. Holmberg, Scott N. Furlan, Antiopi Varelias, Geoffrey R. Hill
Abstract
KRAS is one of the most frequently activated oncogenes in human cancers. While the role of KRAS mutation in tumorigenesis and tumor maintenance has been extensively studied, the relationship between KRAS and the tumor immune microenvironment is not fully understood. Herein, we identified a novel role of KRAS in driving tumor evasion from innate immune surveillance. In lung adenocarcinoma patient samples and Kras-driven genetic mouse models of lung cancer, mutant KRAS activated the expression of cluster of differentiation 47 (CD47), an antiphagocytic signal in cancer cells, leading to decreased phagocytosis of cancer cells by macrophages. Mechanistically, mutant KRAS activated PI3K-STAT3 signaling, which restrained miR-34a expression and relieved the post-transcriptional repression of miR-34a on CD47. In three independent lung cancer patient cohorts, KRAS mutation status positively correlated with CD47 expression. Therapeutically, disruption of the KRAS-CD47 signaling axis with KRAS siRNA, the KRASG12C inhibitor AMG 510 or miR-34a mimic suppressed CD47 expression, enhanced the phagocytic capacity of macrophages and restored innate immune surveillance. Our results revealed a direct mechanistic link between active KRAS and innate immune evasion and identified CD47 as a major effector underlying KRAS-mediated immunosuppressive tumor microenvironment.
Authors
Huanhuan Hu, Rongjie Cheng, Yanbo Wang, Xiaojun Wang, Jianzhuang Wu, Yan Kong, Shoubin Zhan, Zhen Zhou, Hongyu Zhu, Ranran Yu, Gaoli Liang, Qingyan Wang, Xiaoju Zhu, Chen-Yu Zhang, Rong Yin, Chao Yan, Xi Chen
Copyright © 2023 American Society for Clinical Investigation
ISSN: 0021-9738 (print), 1558-8238 (online)