Effect of HMBA on proliferation and expression of KLF6 and related proteins in human tongue carcinoma Tca8113 cells

AIM: To study the effect of hexamethylene bisacetamide(HMBA) on the proliferation and expression of KLF6 and related proteins in human tongue carcinoma Tca8113 cells. METHODS: After cultured with HMBA, the growth of the Tca8113 cells was assayed by MTT method, and the morphology of the cells was observed under microscope. The cell cycle was determined by flow cytometry. The mRNA expression of KLF6 was detected by RT-PCR. The protein levels of KLF6, p53, cyclin D1 and c-Jun were measured by the method of immunohistochemistry. RESULTS: The number of adherent cells obviously decreased along with the concentration of HMBA, and the growth inhibition of Tca8113 cells was in a concentration/time-effect relationship after treated with HMBA. Some reversal features of the Tca8113 cells developed to normal cells in morphology after induced by HMBA. The proportion of the cells in G₁ phase was (52.00?0.02)% before treating with HMBA. The proportion of the cells in S phase was (34.00?0.08)%, and (14.00?0.10)% of G₂ phase cells. After treated with HMBA, the cell number in G₁ phase significantly increased with the exposure time going on, while the cell number in S phase significantly reduced, so did the cell number in G₂ phase. The cell cycle was significantly arrested in G₁ phase (P<0.05). The apoptosis peak also appeared. The mRNA expression of KLF6 significantly increased after induced by HMBA (P<0.05), so did the protein levels of KLF6 and p53 (P<0.05), while the expression of cyclin D1 and c-Jun was significantly decreased (P<0.05). CONCLUSION: HMBA inhibits the proliferation of Tca8113 cells by arresting the cell cycle in G₀/G₁ phase and resuming Tca8113 cells to normal and apoptosis at last.