The Effect of Trichostatin A on Histone Acetylation and mRNA Expression of ING1b Gene in Human Colon Cancer Cell Line Colo205 / 中国肿瘤临床

ABSTRACT

Objective: To investigate the effect of Trichostatin A (TSA) on histone acetylation and expression of ING1b mRNA in Colo205 human colon cancer cell line. Methods: Human colon cancer Colo205 cells were cultured and divided into 4 groups. Cells in the control group (group A) was treated without TSA. In the other three groups, cells were treated with 3 different concentrations of TSA 50μg/L (group B), 100μg/L (group C), and 200μg/L (group D). At 24 hours after treatment, the level of histone H3 acetylation was analyzed by chromatin immunoprecipitation (CHIP) and the expression of ING1b mRNA was detected by RT-PCR with qPCR. The growth of Colo205 human colon cancer cells in group C and D was obviously inhibited compared with that in group A and B. Results: The Ct value of histone H3 acetylation and mRNA expression of ING1b in group A were 23.25± 0.08 and 23.32±0.05, respectively. After treatment with TSA, the 2~(-△△Ct) value of histone H3 acetylation in group B, C, and D were 1.12, 4.21 and 4.38, respectively. The level of histone H3 acetylation in group C and D was increased more compared with that in group A (P<0.05) and there was no difference between group B and group A (P>0.05). The 2~(-△△Ct) value of the expression of ING1b mRNA in group B, C and D were 1.33, 4.52 and 4.62, respectively. The expression of ING1b mRNA in group C and D were more than that in group A (P<0.05). Group B and group A had a similar level of ING1b mRNA expression (P>0.05). Conclusion: The histone acetylation is probably responsible for ING1b expression silencing in Colo205 human colon cell line. TSA at 100μg/L can increase the level of acetylation and activate the gene transcription which is silenced by low level of acetylation and induce the expression of gene, inhibiting the growth of tumor cells.