CSN6: a promising target for cancer prevention and therapy

Mechanisms and potential applications of COPS6 in pan-cancer therapy

The COP9 signalosome subunit 6 (COPS6) is abnormally overexpressed in many malignancies, yet its precise role in carcinogenesis is unknown. To gain a better understanding of COPS6's role, the authors conducted a pan-cancer analysis using various bioinformatics techniques such as differential expression patterns, prognostic value, gene mutations, immune infiltration, correlation analysis, and functional enrichment assessment. Results showed that COPS6 was highly correlated with prognosis, immune cell infiltration level, tumor mutation burden, and microsatellite instability in patients with a range of tumor types. This suggests that COPS6 may be a potential target for cancer treatment. Overall, this research provides insight into COPS6's role in cancer development and its potential therapeutic applications.

Computational exploration of the significance of COPS6 in cancer: Functional and clinical relevance across tumor types

BACKGROUND

The COP9 signalosome subunit 6 (COPS6) has been implicated in cancer progression, while its precise role in most types of cancer remains elusive.

AIM

To investigate the functional and clinical relevance of COPS6 across various tumor types using publicly available databases.

METHODS

We used R software and online analysis databases to analyze the differential expression, prognosis, mutation and related functions of COPS6 in pan-cancer.

RESULTS

Differential expression analysis and survival analysis demonstrated that COPS6 was highly expressed and associated with high-risk profiles in the majority of cancer types. Possible associations between COPS6 expression level and prognostic outcomes were found using data from public databases. Mutational analysis revealed that missense mutations were the predominant type of COPS6 mutation. Additionally, positive correlations were identified between COPS6 expression level and tumor mutational burden and microsatellite instability in most types of cancer. Immune infiltration analysis demonstrated a negative correlation between COPS6 expression level and CD8+ T cell infiltration in certain types of cancer. The correlation between COPS6 expression level and cancer-associated fibroblast infiltration exhibited heterogeneity, in which a positive correlation was found in head and neck squamous cell carcinoma and tenosynovial giant cell tumor, and a negative correlation was identified in diffuse large B-cell lymphoma and thymoma. The correlation between COPS6 expression level and macrophage infiltration was closely related to macrophage type. Gene co-expression and enrichment analysis highlighted transcription elongation factor B polypeptide 2 and G protein pathway suppressor 1 were significantly and positively associated with COPS6 expression level. These genes were predominantly involved in processes, such as ubiquitin-mediated proteolysis and human immunodeficiency virus 1 infection.

CONCLUSION

In conclusion, this study systematically explored the significance of COPS6 across different tumor types, providing a solid foundation for considering COPS6 as a novel biomarker in cancer research.

CSN6 promotes melanoma proliferation and metastasis by controlling the UBR5-mediated ubiquitination and degradation of CDK9

As a critical subunit of the constitutive photomorphogenesis 9 (COP9) signalosome (CSN), CSN6 is upregulated in some human cancers and plays critical roles in tumorigenesis and progression, but its biological functions and molecular mechanisms in melanoma remain unknown. Our study showed that CSN6 expression was upregulated in melanoma patients and cells, and correlated with poor survival in melanoma patients. In melanoma cells, CSN6 knockdown remarkably inhibited cell proliferation, tumorigenicity, migration, and invasion, whereas CSN6 recovery rescued the proliferative and metastatic abilities. Notably, we identified that CSN6 stabilized CDK9 expression by reducing CDK9 ubiquitination levels, thereby activating CDK9-mediated signaling pathways. In addition, our study described a novel CSN6-interacting E3 ligase UBR5, which was negatively regulated by CSN6 and could regulate the ubiquitination and degradation of CDK9 in melanoma cells. Furthermore, in CSN6-knockdown melanoma cells, UBR5 knockdown abrogated the effects caused by CSN6 silencing, suggesting that CSN6 activates the UBR5/CDK9 pathway to promote melanoma cell proliferation and metastasis. Thus, this study illustrates the mechanism by which the CSN6-UBR5-CDK9 axis promotes melanoma development, and demonstrate that CSN6 may be a potential biomarker and anticancer target in melanoma.