Abstract: eukaryotic initiation factor subunit c (eIF3c) has been identified as an oncogene that is over-expressed in tumor cells and, therefore, is a potential therapeutic target for gene-based cancer treatment. This study was focused on investigating the effect of small interfering RNA (siRNA)-mediated eIF3c gene knockdown on colon cancer cell survival. The eIF3c gene was observed to be highly expressed in colon cancer cell models. The expression levels of the gene in eIF3c siRNA infected and control siRNA infected cells were compared via real-time polymerase chain reaction (PCR) and western blotting analysis. Cell proliferation levels were analyzed employing 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and colony formation assays. Furthermore, the effects of eIF3c gene knockdown on the cell cycle and apoptosis were analyzed using flow cytometry. The results showed that suppression of eIF3c expression significantly (P<0.001) reduced cell proliferation and colony formation of RKO colon cancer cells. The cell cycle was arrested by decreasing the number of cells entering S phase. Further, apoptosis was induced as a result of eIF3c knockdown. Collectively, eIF3c deletion effectively reduced the survival of colon cancer cells and could be used as a therapeutic tool for colon cancer therapy.

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