BDE-209-exposed melanoma cells enhance metastasis and chemoresistance in C57BL/6 mice.

Decabromodiphenyl ether (BDE-209) is a commonly used additive in plastics, primarily used as a flame retardant, and is classified as a persistent organic pollutant. Melanoma is the most aggressive type of skin cancer due to its high capacity for distant metastatic spread and high lethality. Therefore, the current study aimed to investigate the in vivo role of BDE-209 in the progression, malignancy and chemotherapy treatment of melanoma. After the experimental metastasis assay (20 days), the animals inoculated with B16-F1 cells previously exposed at a low concentration to BDE-209 (1 nM), and also under chemotherapy treatment presented an increase in lung mass, colonized lung surface metastases, metastatic lesion index, and downregulation of the tumor suppressor Timp3. Furthermore, an increase in the size of plasma extracellular vesicles (EVs), an over-expression of Abcb1, and alterations of Abcc4 and Cd44 gene expression were observed. The higher incidence of metastasis and over-expression of Abcb1 in individuals previously exposed to BDE-209 indicate the importance of investigating environmental pollutants in cancer progression and chemoresistance. These datasets suggest the potential effect of BDE-209 on the phenotypic modulation of murine melanoma cells (B16-F1) in vivo, affecting melanoma treatment and inducing tumor progression.