Abstract:

Objective To investigate effects of trichosanthin (TCS) on apoptosis and proliferation of colorectal cancer (CRC) cell line CMT-93. Methods CMT-93, a mouse colorectal cell line cultured in vitro, was treated by TCS of different mass concentrations. The control group was CMT-93 without being treated by TCS. The activity of cell proliferation was measured by the Real-Time Cellular Analysis (RTCA) system. The proliferation and apoptosis was detected by the flow cytometry. Real-Time PCR was used to evaluate gene expressions related to the apoptosis. Expressions of Akt and γ-H2AX and the phosphorylation level of Akt (pAkt 473 and pAkt 308)  were assayed by the Western blotting. Results Compared to the control group, TCS of 5.0 μg/mL significantly inhibited the cell viability of CMT-93 cells and induced apoptosis of CMT-93 cells. The mRNA levels of Bid, Bax, and Bad were up-regulated in TCS-treated group. The expressions of pAkt 473 and pAkt 308 decreased significantly after treated by TCS, while the expression of γ-H2AX increased. Conclusion The results suggest that TCS can induce the apoptosis and inhibit the proliferation of CMT-93 cells. The mechanism may be relevant to inhibiting the expressions of active proapoptotic related proteins of Akt and DNA damage of the TCS.

Key words: trichosanthin, colorectal cancer, cell apoptosis, cell proliferation