Oncogene最新文献

Immunotherapy remains ineffective for a wide variety of solid tumors due to the existence of tumor immune evasion. Although the transcription factor ETV5 is recognized for its oncogenic roles in tumor progression, its role in remodeling the immunosuppressive microenvironment remains largely unexplored. Here, we reveal that tumor-intrinsic ETV5 drives immune evasion and immune checkpoint inhibitor (ICI) resistance by enhancing the expansion and recruitment of polymorphonuclear myeloid-derived suppressor cells (PMN-MDSCs). Genetic silencing of ETV5 in murine tumor models suppressed PMN-MDSCs differentiation from myeloid progenitors, reduced their tumor infiltration, and attenuated immunosuppressive function, resulting in enhanced cytotoxic T cell activity and delayed tumor progression. Mechanistically, ETV5 directly binds to the JH1 domain of JAK2, inducing its dimerization and phosphorylation, which activates STAT3 to transcriptionally upregulate CCL2 and recruit PMN-MDSCs. Therapeutically, ETV5 ablation synergized with anti-PD-L1 therapy to enhance tumor control, mirroring clinical observations where high ETV5 expression predicted immunotherapy resistance. Our study uncovers a non-canonical, transcription-independent role of ETV5 in orchestrating the JAK2/STAT3/CCL2 axis to sustain PMN-MDSC-mediated immune evasion, proposing ETV5 as a druggable target to overcome ICI resistance in solid tumors.

Prostate cancer is dependent upon the androgen receptor (AR), the activity of which is modified by cofactors that either enhance or repress its activity, often in a context-dependent manner. FUS/TLS is a multifunctional protein known to be important in multiple cancer types; in prostate cancer, we previously showed that FUS has a potential tumour suppressor role. Here, transcriptomic analysis of the LNCaP prostate cancer cell line shows a significant overlap in genes regulated by FUS and the androgen receptor. We demonstrate that FUS can regulate androgen receptor activity, in either direction, but predominantly represses androgen signalling. Reporter assays and domain-specific analyses of FUS identified mechanisms by which FUS modifies androgen receptor activity. FUS interacts with the androgen receptor and other cofactors to repress transcription; ChIP assays suggest that repression occurs via disassembly of the transcriptional complex. Quantitative proteomics and RNA-Seq were used to investigate FUS expression in patient samples across prostate cancer stages. FUS was found to be down-regulated in primary tumours, but up-regulated in advanced aggressive stages. These findings suggest that in early prostate cancer, FUS represses AR activity and tumour progression, leading to its down-regulation. In contrast, increased FUS expression in advanced disease appears to be linked to a loss of AR regulatory control.

Ovarian cancer (OCa) remains the most lethal gynecologic malignancy in the United States, with a five-year survival rate below 20%. Elevated basal levels of endoplasmic reticulum stress (ERS) have recently emerged as a therapeutic vulnerability in OCa. We have previously shown that the tris-benzamide ERX-41 can induce ERS and cancer cell death in OCa by targeting LIPA. In this study, using iterative structure-activity relationship-guided studies to enhance activity in OCa, we identified a more potent ERX-41-derived analog, ERX-208. Importantly, ERX-208 consistently and significantly reduced cell viability in 23 OCa cell lines spanning five major histological OCa subtypes, with IC₅₀ values ranging from 50-100 nM, compared to ∼500 nM for ERX-41. Notably, ERX-208 showed minimal cytotoxicity toward normal ovarian surface epithelial cells, indicating cancer cell selectivity. ERX-208 induced apoptosis and suppressed colony formation in vitro in OCa cells. Mechanistic studies using RNA sequencing, Western blotting, RT-qPCR, transmission electron microscopy, and immunohistochemistry validated robust activation of ERS pathways upon ERX-208 treatment. Through in silico molecular docking simulation and confirmatory detailed site-directed mutagenesis, we identified that ERX-208 binds to LIPA over a broader interaction surface than ERX-41. At the 10 mg/kg dose, ERX-208 demonstrated favorable biodistribution, no observable toxicity, and potent antitumor efficacy in vivo against established cell line-derived xenograft (CDX), patient-derived xenograft (PDX), and patient-derived explant (PDE) models. Immunohistochemical analysis of treated tumors demonstrated changes in expression of proliferative marker (ki67, decreased) and the ERS marker (GRP78, increased). These findings support the clinical advancement of ERX-208 for the treatment of patients with OCa.

Bladder cancer remains a clinically challenging malignancy, with increasing evidence suggesting that chronic bladder inflammation, such as interstitial cystitis (IC), may contribute to its development. However, the molecular mechanisms linking inflammation to tumorigenesis are poorly understood. Here, we identify coiled-coil domain-containing 8 (CCDC8) as a potential oncogenic factor in bladder cancer. Transcriptomic analysis revealed that CCDC8 is dysregulated in both IC and bladder cancer, with overexpression confirmed in tumor tissues and cell lines. Elevated CCDC8 expression was significantly associated with advanced tumor stage, lymph node metastasis, and poor prognosis, particularly in patients harboring wild-type TP53. Functional studies demonstrated that CCDC8 promotes tumor cell proliferation, migration, and survival in vitro, and enhances tumor growth in vivo. Mechanistically, CCDC8 interacts with the E3 ubiquitin ligase scaffold protein CUL7, facilitating proteasome-dependent degradation of P53, thereby suppressing its downstream effectors such as P21 and BAX. Pharmacological inhibition of neddylation with MLN4924 restored P53 levels and reversed the oncogenic effects of CCDC8 both in vitro and in vivo. Together, these findings highlight a novel mechanism of P53 regulation in bladder cancer, position CCDC8 as a potential biomarker and therapeutic target, and suggest a molecular link between chronic bladder inflammation and malignant transformation.