Transforming Growth Factor Beta 1 Affects Gastric Cancer Cell Proliferation, Migration, and Invasion by Regulating Phosphatase and Tensin Homolog

Gastric cancer (GC) is a common tumor with high incidence and poor prognosis. So far, the pathogenesis of GC has not been fully elucidated, which has brought great difficulty to the treatment. TGF-β regulates cell growth and differentiation. As a key member, TGF-β1 is abnormally expressed in various tumors, but its role on GC and related mechanisms have not been elucidated. Gastric cancer and adjacent tissues were collected to measure TGF-β1 level by real-time PCR. SGC-7901 cell was assigned into control group, mock group, and TGF-β1 siRNA group followed by analysis of TGF-β1 level by ELISA, cell proliferation by MTT assay, apoptosis by flow cytometry, cell migration by cell scratch test, cell invasion by Transwell chamber assay, and Bcl-2, Bax, and PTEN level by Western blot. TGF-β1 was significantly upregulated in GC tissues ( P <0.05) and increased with TNM stage dependence. TGF-β1 siRNA transfection significantly decreased TGF-β1 mRNA level and secretion, inhibited cell proliferation, increased apoptosis rate, and attenuated cell migration and invasion along with downregulated Bcl-2 and elevated Bax and PTEN expression ( P <0.05). Downregulation of TGF-β1 can promote gastric cancer cell apoptosis, inhibit proliferation, migration, and invasion by regulating PTEN.