Effect of transient TCDD exposure on immortalized human trophoblast-derived cell lines

Low level, antenatal exposure to dioxins is associated with low birth weight, which in turn is associated with long-term sequelae. We exposed the human extravillous cytotrophoblast (EVT) lines HTR-8/SV40 and TCL1 to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and assessed cell growth, invasion, and differentiation. TCDD had no effect on cell proliferation, invasion, or tube formation in Matrigel. The EVT-derived cells expressed a functional aryl hydrocarbon receptor protein; however, TCDD exposure did not alter expression levels of proteins involved in EVT differentiation in early pregnancy, including hypoxia-inducible factor 1A (HIF1A), vascular endothelial growth factor (VEGF), Integrin A1, A6, and AVB3. These results suggest that the reduction in fetal weight induced by dioxin is not the result of vascular remodeling via EVT dysfunction.