Abstract:

 Objective  This paper aims to study the effects of gossypol acetic acid (GAA) on proliferation and methylation level of human MutL homologue 1 (hMLH1) gene in human tongue cancer cell line Tca8113. Methods The MTT assay was used to determine the effects of the acid on the proliferation inhibition in Tca8113 cells treated with different GAA concen-trations. Nested methylation-specific polymerase chain reaction (nMSP) was used to detect the change in the methylation level of hMLH1 after 48 and 72 h with 30 and 15 μmol•L-1 GAA treatment. Results  MTT assay results showed the growth and proliferation inhibition of Tca8113 cells in the experimental GAA group after 24h to 72 h of GAA treatment. The nMSP results indicated that the average optical density of hMLH1 in the Tca8113 cells significantly changed after the GAA treat-ment (30 μmol•L.1 GAA for 48 h and 15 μmol•L.1 for 72h) (P<0.05) compared with that of the control group. Conclusion  GAA does not only inhibit Tca8113 proliferation but also has a demethylation effect on the hMLH1 gene. These phenomena may be part of an underlying tumor-suppression mechanism of GAA.

Key words:  Tca8113 cell, gossypol, tumor suppressor gene, methylation