Nuclear β-catenin expression is positively regulated by JAB1 in human colorectal cancer cells

Expression and potential molecular mechanism of TOP2A in metastasis of non-small cell lung cancer

DNA topoisomerase II alpha (TOP2A) expression, gene alterations, and enzyme activity have been studied in various malignant tumors. Abnormal elevation of TOP2A expression is considered to be related to the development of non-small cell lung cancer (NSCLC). However, its association with tumor metastasis and its mode of action remains unclear. Bioinformatics, real-time quantitative PCR, immunohistochemistry and immunoblotting were used to detect TOP2A expression in NSCLC tissues and cells. Cell migration and invasion assays as well as cytoskeletal staining were performed to analyze the effects of TOP2A on the motility, migration and invasion ability of NSCLC cells. Cell cycle and apoptosis assays were used to verify the effects of TOP2A on apoptosis as well as cycle distribution in NSCLC. TOP2A expression was considerably upregulated in NSCLC and significantly correlated with tumor metastasis and the occurrence of epithelial-mesenchymal transition (EMT) in NSCLC. Additionally, by interacting with the classical ligand Wnt3a, TOP2A may trigger the canonical Wnt signaling pathway in NSCLC. These observations suggest that TOP2A promotes EMT in NSCLC by activating the Wnt/β-catenin signaling pathway and positively regulates malignant events in NSCLC, in addition to its significant association with tumor metastasis. TOP2A promotes the metastasis of NSCLC by stimulating the canonical Wnt signaling pathway and inducing EMT. This study further elucidates the mechanism of action of TOP2A, suggesting that it might be a potential therapeutic target for anti-metastatic therapy.

Pan-cancer analyses of Jab1/COPS5 reveal oncogenic role and clinical outcome in human cancer

Jab1/COPS5 is associated with the progression of some cancers, however, its role in most cancers is still unclear.This study systematically explored the action and clinical application value of Jab1/COPS5 in different tumors based on large clinical data. We first identified by differential and survival analysis that Jab1/COPS5 was highly expressed as a high-risk gene in most cancers and was closely related to prognostic survival of patients based on the TCGA, GEO and CPTAC databases. Mutation analysis suggested that missense mutations were the main mutation type of Jab1. TMB and MSI were positively correlated with Jab1/COPS5 in most tumors, and patients with Jab1/COPS5 mutations had a poorer prognosis in prostate adenocarcinoma. By immune infiltration analysis, Jab1/COPS5 expression was positively correlated with the infiltration of CD8+ T cells in thymoma and uveal melanoma, and Jab1/COPS5 expression in testicular germ cell tumors was negatively correlated with the infiltration of cancer-associated fibroblasts. Correlation and enrichment analysis suggested that ARMC1, TCEB1 and UBE2V2 were positively correlated with Jab1/COPS5 expression and involved in multiple biological effects. In summary, this study systematically investigated the role of Jab1/COPS5 in different tumors, providing a theoretical basis for Jab1/COPS5 as a new biomarker in unresearched cancers and paving the way for targeted therapy and drug development.

Prognostic and therapeutic significance of COP9 signalosome subunit CSN5 in prostate cancer

Chromosome 8q gain is associated with poor clinical outcomes in prostate cancer, but the underlying biological mechanisms remain to be clarified. CSN5, a putative androgen receptor (AR) partner that is located on chromosome 8q, is the key subunit of the COP9 signalosome, which deactivates ubiquitin ligases. Deregulation of CSN5 could affect diverse cellular functions that contribute to tumor development, but there has been no comprehensive study of its function in prostate cancer. The clinical significance of CSN5 amplification/overexpression was evaluated in 16 prostate cancer clinical cohorts. Its oncogenic activity was assessed by genetic and pharmacologic perturbations of CSN5 activity in prostate cancer cell lines. The molecular mechanisms of CSN5 function were assessed, as was the efficacy of the CSN5 inhibitor CSN5i-3 in vitro and in vivo. Finally, the transcription cofactor activity of CSN5 in prostate cancer cells was determined. The prognostic significance of CSN5 amplification and overexpression in prostate cancer was independent of MYC amplification. Inhibition of CSN5 inhibited its oncogenic function by targeting AR signaling, DNA repair, multiple oncogenic pathways, and spliceosome regulation. Furthermore, inhibition of CSN5 repressed metabolic pathways, including oxidative phosphorylation and glycolysis in AR-negative prostate cancer cells. Targeting CSN5 with CSN5i-3 showed potent antitumor activity in vitro and in vivo. Importantly, CSN5i-3 synergizes with PARP inhibitors to inhibit prostate cancer cell growth. CSN5 functions as a transcription cofactor to cooperate with multiple transcription factors in prostate cancer. Inhibiting CSN5 strongly attenuates prostate cancer progression and could enhance PARP inhibition efficacy in the treatment of prostate cancer.