Autophagy induction of reversine on human follicular thyroid cancer cells

The incurable differentiated thyroid cancer (DTC), poorly differentiated thyroid cancer (PDTC) and anaplastic thyroid cancer (ATC) are the most aggressive in all of the thyroid cancers. Unfortunately, there are almost no effective therapies. A novel and effective treatment is urgently needed to develop. Recently, reversine, a small synthetic purine analogue, has been reported to be effective in human thyroid cancer suppression through cell cycle arrest and apoptosis induction. In this study, we performed an in vitro evaluation of reversine on autophagy activation, one of the programmed cell death, and the related mechanisms in human follicular thyroid cancer cell line WRO. Incubation of WRO cells with reversine induced autophagosome formation in a short time treatment. LC3-II overexpression in a dosage-dependent manner with reversine treatment was demonstrated in the autophagy activation. Moreover, reversine suppressed Akt/mTOR related signaling pathway activation, a major pathway for autophagy activation, was also revealed in WRO cells. Our data demonstrated that reversine is effective to induce autophagy. Moreover, the LC3-II overexpression and the p62 protein were degraded in a time-dependent manner, indicating that the autophagic flux has happened in the reversine treated WRO cells. In addition, the activation of Akt/mTOR/p70S6 K related pathways were shown to be reduced, suggesting these pathways may involve in the reversine mediated autophagy induction. Reversine is therefore worthy of further investigation in clinical therapeutics. (C) 2012 Elsevier Masson SAS. All rights reserved.