Dihydrotanshinone exerts antitumor effects and improves the effects of cisplatin in anaplastic thyroid cancer cells

Anaplastic thyroid cancer (ATC) is the most aggressive type of thyroid cancer and is responsible for 20-50% of thyroid-associated cancers deaths. The absence of response to conventional treatments makes the search for novel therapeutics an urgent clinical challenge. In the present study, the effects of 15,16-dihydrotanshinone I (DHT), a tanshinone extracted from Salvia miltiorrhiza Bunge (Danshen), which has been shown to possess anticancer activity, were examined on two human ATC cell lines. DHT significantly reduced cell viability, coupled with an increase in apoptosis. DHT administration was also able to reduce the colony-forming ability and the growth in soft agar and downregulate the expression of certain epithelial-to-mesenchymal transition-related genes. In addition, DHT significantly reduced MAD2 expression, a target of HuR with a relevant role in ATC. Finally, cotreatment with cisplatin and DHT augmented their effects on cell viability compared with each compound alone. In conclusion, to the best of our knowledge, the present study is the first to demonstrate that DHT exerts antitumor effects on ATC cells by reducing MAD2 expression levels. Moreover, a synergistic effect of DHT with cisplatin was shown, and thus further in vivo studies are required to assess this phytochemical compound as a potential adjuvant for the treatment of ATC. mRNA profiles of SW1736 and 8505C DHT treated or untreated cells