p53 Deficiency in Colon Cancer Cells Promotes Tumor Progression Through the Modulation of Meflin in Fibroblasts

Area of Science:

• Oncology
• Cancer Biology
• Tumor Microenvironment

Background:

• Cancer-associated fibroblasts (CAFs) are key players in tumor progression.
• Colon cancer cells with p53 deficiency enhance fibroblast activity and tumor growth.
• Meflin, a CAF marker, has demonstrated tumor growth inhibitory properties.

Purpose of the Study:

• To investigate the role of Meflin in fibroblasts within the context of colon cancer.
• To elucidate the mechanism by which p53-deficient colon cancer cells influence fibroblast behavior and Meflin expression.
• To evaluate Meflin as a potential therapeutic target in colorectal cancer.

Main Methods:

• Co-culture experiments using human colon cancer (HCT116) and fibroblast (CCD-18Co) cell lines.
• Xenograft tumor models in mice to assess tumor growth.
• Analysis of CAF-specific markers and Meflin expression levels.
• Manipulation of Meflin expression using siRNA and lentivirus.
• Investigation of Meflin regulation by TGF-β and vitamin D.

Main Results:

• TP53-suppressed HCT116 cells promoted faster proliferation and larger tumor volumes compared to control cells.
• HCT116^{sh p53} cells induced a CAF-like phenotype in CCD-18Co cells, with reduced Meflin expression.
• si-RNA mediated Meflin inhibition in fibroblasts enhanced tumor growth, while Meflin overexpression suppressed it.
• Meflin expression was suppressed by TGF-β and enhanced by vitamin D in fibroblasts.

Conclusions:

• Colon cancer cells deficient in p53 suppress Meflin expression in fibroblasts, thereby promoting tumor growth.
• Altering Meflin expression in fibroblasts significantly impacts tumor growth.
• Targeting Meflin in fibroblasts presents a potential novel therapeutic strategy for colorectal cancer.