Di(2-ethylhexyl) phthalate (DEHP) is a common plasticizer that is widely used in many consumer products and medical devices. Humans can be exposed to DEHP through ingestion, inhalation, or dermal absorption. Previous studies on DEHP have focused on its role as an endocrine-disrupting chemical leading to endocrine-related diseases. However, the correlation between DEHP exposure and the progression of colorectal cancer (CRC) is largely unknown. The aim of this study was to investigate the effects of mono(2-ethylhexyl) phthalate (MEHP), an active metabolite of DEHP, on the progression of CRC. Our results showed that treatment with MEHP enriched the population of cancer-stem-cell (CSC)-like cells and upregulated IL-8 expression by inducing the AKT-β-catenin-TCF4 signaling pathway. Blocking β-catenin-TCF4-mediated IL-8 expression reversed the MEHP-induced migration and enrichment of CSC-like cells. Consistent with the in vitro data, DEHP treatment increased the levels of nuclear β-catenin, polyp formation, and invasive adenocarcinoma in a mouse model. Our results suggest that MEHP facilitates the progression of CRC through AKT-β-catenin signaling.
Keywords: AKT; IL-8; MEHP; cancer stem cells; colorectal cancer; β-catenin.