LncRNA-CASC7 inhibits the proliferation and migration of colon cancer by negatively regulating the PI3K/Akt signaling pathway

Background: This study aims to investigate the effect of LncRNA-CASC7 (cancer susceptibility candidate 7) on the proliferation and migration of colon cancer cells and its possible mechanism. Methods: In this study, quantitative real-time polymerase chain reaction (qRT-PCR) was employed for the detection of lncRNA-CASC7 expression in 54 colon cancer tissues and 5 colon cancer cell lines. This study aimed to evaluate the significant correlation between the lncRNA-CASC7 expression, the clinical features, and the survival rate of patients. LncRNA-CASC7 was overexpressed by lipofectin transfection. Cell proliferation was detected by the methyl thiazolyl tetrazolium (MTT) assay. Transwell assay was conducted to examine cell migration and invasion. The target gene was verified by dual fluorescein. The expression of proliferation and invasion-related proteins was detected via western blotting (WB). Results: The LncRNA-CASC7 expression in colon cancer was considerably decreased than in nearby healthy tissues (P<0.01). Its expression level was linked to survival rate, lymph node metastasis, and tumor node metastasis (TNM) stage. Similarly, the expression of lncRNA-CASC7 was decreased in 5 colon cancer cell lines. The proliferative, invasive, and migratory potential of cells was considerably decreased by lncRNACASC7 overexpression. Overexpression of lncRNA-CASC7 significantly inhibited the expression of proteins Ki-67 and PNCA (associated with proliferation) and proteins N-cadherin, E-cadherin, and vimentin (linked with metastasis). Further studies showed that overexpression of LncRNA-CASC7 could significantly inhibit the PI3K/Akt signaling pathway in colon cancer cells. Conclusions: The PI3K/Akt signaling cascade is negatively regulated by LncRNA-CASC7, which serves as a tumor suppressor gene by attenuating colon cancer cell proliferation, invasion, and migration, thus affecting the tumor progression and prognosis of colon cancer patients.

Automated summary

The expression of LncRNA-CASC7 was significantly decreased in colon cancer tissues compared to nearby healthy tissues, and was associated with survival rate, lymph node metastasis, and TNM stage. Overexpression of LncRNA-CASC7 inhibited cell proliferation, invasion, and migration in colon cancer cells, and also suppressed the PI3K/Akt signaling pathway.