CCT7 predicts poor prognosis and correlates with immune infiltration in colonic adenocarcinoma

TL;DR

CCT7 is overexpressed in colon cancer, linked to worse outcomes and immune cell infiltration, suggesting it could be a new biomarker and therapeutic target.

Contribution

This study identifies CCT7 as a novel prognostic biomarker and potential therapeutic target in colonic adenocarcinoma.

Findings

CCT7 is significantly upregulated in COAD tissues and associated with poor prognosis.

CCT7 knockdown reduces cancer cell proliferation, migration, and invasion.

CCT7 negatively correlates with immune cell infiltration but not with checkpoint inhibitor therapy response.

Abstract

CCT7, a member of the t-complex polypeptide 1 chaperone family, facilitates ATP-dependent protein folding; however, its role in development and progression of malignant tumors remains unclear. This study aimed to characterize the expression pattern of CCT7 in colonic adenocarcinoma (COAD) and evaluate its role in the initiation and development of COAD. Public bioinformatic databases were analyzed to assess CCT7 expression in COAD, and these findings were validated using human clinical specimens through immunohistochemistry (IHC) assay. The prognostic significance of CCT7 was examined using Kaplan–Meier method and Cox regression analysis. Gene Ontology-Biological Process (GO-BP) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were performed to explore the potential biological functions and downstream pathways associated with CCT7. CCK-8, colony formation and Transwell assays were conducted to determine the impact of CCT7 on cell proliferation, migration and invasion in COAD cell lines. Associations between CCT7 expression and immune cell infiltration or drug sensitivity were evaluated using single-sample gene set enrichment analysis and correlation analysis. Finally, immune checkpoint inhibitor therapy scores and their relationship with CCT7 expression were assessed using data from The Cancer Immunome Atlas. CCT7 expression was significantly up-regulated statistically in COAD tissues compared with normal colonic tissues (P< 0.05) and elevated CCT7 levels were associated with poorer prognosis of COAD patients (P< 0.05). GO-BP enrichment analysis indicated that CCT7 was primarily involved in the processes related to cell proliferation and microtubule organization (P< 0.05). Consistently, functional assays confirmed that CCT7 knockdown inhibited COAD cell proliferation, migration, and invasion (P< 0.05). CCT7 expression showed a negative correlation with infiltration of most immune cell types (P< 0.05) and demonstrated no significant association with predicted responses to PD-1 and CTLA-4 inhibitor therapies (P> 0.05). Moreover, drug sensitivity analyses showed that CCT7 affected the sensitivity of COAD samples to several anti-cancer drugs (P< 0.001). KEGG enrichment analysis revealed that CCT7 was associated with multiple pathways (P< 0.05). CCT7 may function as an oncogenic driver that promotes the malignant phenotype of COAD and represents a promising prognostic biomarker. It may also provide a valuable reference for guiding clinical therapeutic strategies in COAD.

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