The effect of HDAC inhibitor SNDX-275 on inhibiting breast cancer BT474 cell proliferation

Abstract

Objective To explore the effect and molecular mechanism of HDAC inhibitor SNDX-275 inhibiting cell proliferation in ErbB2-overexpressing breast cancer BT474 cells. Methods Breast cancer BT474 cells were treated with HDAC inhibitor SNDX-275, setting as test group, and the cell line treated with phosphate buffered saline (PBS) as control. The concentration of SNDX-275 were 0, 0.5, 1.0, 2.0, 3.0, 4.0 μmol/L respectively. Cell proliferation was analyzed by MTS assay and colony formation assay, the expressions of ErbB2, ErbB3, p-Akt were analyzed by Western blotting, and the expressions of miR-125a, miR-125b were analyzed by RT-PCR. After transfecting miRNA125 inhibitor into BT474 cells, the inhibition rate of SNDX-275 was tested by MTS assay . Results MTS result showed that SNDX-275 inhibited cell proliferation in BT474 cells in a dose-dependent manner. The inhibition rate of 4.0 μmol/L SNDX-275 was about (68.00±4.45)%. Clone assay indicated SNDX-275 could inhibit the proliferation of BT474 cells. Western blotting result indicated that SNDX-275 significantly inhibited the protein expressions of ErbB2, ErbB3 and p-Akt, RT-PCR result illustrated 2 μmol/L SNDX-275 could increase the expressions of miR-125a and miR-125b about 3.22±1.17, 5.42±0.38 times compared with the PBS control respectively, the difference has a statistical significance (t=4.338, P=0.049; t=21.805, P=0.002). MTS result indicated that compared with the PBS control, the inhibition rate of SNDX-275 group was (56.97±3.56)%, while the inhibition rate of SNDX-275 and miRNA125 inhibitor group was (10.67±2.21)%, with a statistical significance(t=-10.993, P=0.008). Conclusion SNDX-275 could inhibit cell proliferation of ErbB2-overexpressing breast cancer BT474 cells, by inhibiting ErbB2-ErbB3-Akt signal pathway through up-regulating miR-125a and miR-125b. Key words: Breast neoplasms; Cell proliferation; MicroRNAs