Mir-140 Inhibits The Larynx Cancer Proliferation, Promotes Cellular Apoptosis And Cycle Arrest Through Degrading Sry-Box Transcription Factor 4 (Sox4)

To study miR-140 and SOX4 levels in larynx cancer cells and elucidate the effects of miR-140 and SOX4 in the pathogenesis of larynx cancers and understand the pathogenesis of larynx cancer. miR-140 level in larynx cancer tissues and cell lines was measured by Real time PCR. Flow cytometry, MTT assay, cell count and cell transfection were carried out to determine the effects of miR-140 and SOX4 on the cellular proliferation, apoptosis and cycle in larynx cancers. SOX4 level was detected by Western blotting and real time PCR. The targeting relationship of miR-140 with SOX4 was analyzed by dual-luciferase reporter assay. miR-140 in larynx cancer tissue of the patients and larynx cancer cell lines was significantly lower than that in pericarcinomatous tissue and its level in early stage I-II larynx cancer tissue was significantly lower than that in late stage III-IV larynx cancer tissue. miR-140 in larynx cancer cells had a positive correlation with cell apoptosis and a negative correlation with cell invasion and proliferation; miR-140 mimics can induce cell cycle arrest in G0/G1 phase. miR-140 directly targeted SOX4 and inhibited SOX4 expression. miR-140 inhibits cellular proliferation in larynx cancers through direct regulation of SOX4, which provides a new theoretical basis and therapeutic target for treating larynx cancers.