Down-regulation of FOXR2 inhibits hypoxia-driven ROS-induced migration and invasion of thyroid cancer cells via regulation of the hedgehog pathway.

Forkhead box R2 (FOXR2), a new member of the FOX family, is involved in a wide range of biological processes such as embryogenesis, differentiation, transformation and metabolic homeostasis. Recently, FOXR2 has been reported to be aberrantly expressed in a variety of cancers and correlated with cancer development. However, the specific role of FOXR2 in thyroid cancer (TC) remains unclear. In this study, we showed that FOXR2 was highly expressed in TC tissues and cell lines. Moreover, down-regulation of FOXR2 inhibited hypoxia-induced reactive oxygen species (ROS) production and migration/invasion of TC cells. We also found that the hedgehog pathway was responsible for the partial mechanisms underlying the inhibitory effect. Taken together, these findings indicated that down-regulation of FOXR2 inhibits hypoxia-driven ROS-induced migration and invasion of TC cells via regulation of the hedgehog pathway. Thus, FOXR2 may hold great potential for TC treatment.