RUNX3 inhibits cell proliferation and induces apoptosis by TGF-beta-dependent and -independent mechanisms in human colon carcinoma cells.

Background: Genes involved in the TGF-beta signaling pathway are often altered in several types of cancers. The TGF-beta-resistant human colon cancer cell line HT-29 has inactivated TbetaRII and deficient expression of RUNX3 and Smad4, which are involved in the TGF-beta signaling pathway.

Methods: Western blot and immunocytochemistry were performed to confirm gene expression, the MTT assay to detect cell growth, flow cytometry to investigate the cell cycle and the TUNEL to detect cell apoptosis.