Paclitaxel-sensitization enhanced by curcumin involves down-regulation of nuclear factor-κB and Lin28 in Hep3B cells

Abstract

Although paclitaxel is an effective chemotherapeutic drug used in the treatment of many tumors, hepatoma cells, in particular, are known to be highly resistant to it. Previously, we discovered that Lin28 was closely associated with resistance to paclitaxel in Hep3B cells. The nuclear factor-kappa B (NF-κB) transcription factor, which plays an important role in tumor survival, directly activates Lin28 expression through a binding site on the first intron. Curcumin, a non-toxic anti-inflammatory agent, inhibits NF-κB activity in vitro. In this study, we reported that a combination of curcumin and paclitaxel exhibited synergistic anti-proliferative and pro-apoptosis effects on Hep3B cells, and curcumin down-regulated paclitaxel-induced enhanced expression of Lin28 and NF-κB activation. Furthermore, our results revealed that curcumin reduced Lin28 levels via mechanisms directly mediated by inhibition of NF-κB activity. These mechanism-based observations evidence that curcumin enhances the sensitivity of hepatoma cells to paclitaxe, and strongly support the notion that paclitaxel in combination with curcumin may provide a superior therapeutic index for HCC chemotherapy.

• Curcuma longa
• hepatocellular carcinoma
• Lin28
• NF-κB
• paclitaxel
• Taxus brevifolia
• curcumin

Declaration of interest

This study was supported in part by research fund for the Doctoral Program of Higher Education of China (no. 20133322120002), Zhejiang Medical and Health Science and Technology Project (no. 2014KYA150), Science and Technology Creative Activity Plan for University Students in Zhejiang Province (no. 2014R410020) and Natural Science Foundation of Zhejiang Province, Youth Fund Project (no. LQ12C07001). The authors declare no conflicts of interests.