2,3,7,8-Tetrachlorodibenzo-
p-dioxin (
TCDD) effectively induces
cleft palate at increased doses, but its mechanism of involvement is unclear, and arguments have examined palatal shelf contact and/or fusion failure. The role of different types of cells constituting palatal skulls remains elusive regarding
TCDD dosage. No reports have simultaneously compared the
biological behaviors of
TCDD- induced mesenchymal and epithelial cells in vitro. This study employed primary epithelial and mesenchymal cells as models in vitro to explore proliferation, migration, apoptosis and epithelial-to-mesenchymal transition with two different doses of
TCDD (10 nmol/L, 100 nmol/L), contrasted with a control group without
TCDD. Interestingly, we found the EMT process of primary palatal epithelial cells occurred automatically in vitro without helping bilateral palatal contact. The results showed that, with the low dose of
TCDD, transformation of epithelial cells to mesenchymal cells was inhibited, and mesenchymal cell proliferation and migration were promoted. At high doses, mesenchymal cells decreased, preventing palate development, uprising and contact, while the EMT of epithelial cells decreased. Regardless of dose of
TCDD, no impact on migration and apoptosis of epithelial cells was noted, but there was increased apoptosis of mesenchymal cell in a dose-dependent manner.