Dulcitol suppresses proliferation and migration of hepatocellular carcinoma via regulating SIRT1/p53 pathway

Background: Hepatocellular carcinoma (HCC) spreads further with continuance and increasing incidence due to its high-grade malignancy and metastasis. More effectual strategies on blocking proliferation and metastasis of cancer cells should be studied in HCC. Dulcitol, a natural product extracted from euonymus alatus, was reported that it could induce apoptosis of C6 glioma cells. However, the underlying mechanism of Dulcitol on HCC remains unclea. Purpose: In this study, we aimed to reveal the effect and potential mechanisms of Dulcitol on hepatocellular carcinoma in vitro and in vivo. Study design and methods The cell proliferation and apoptosis were evaluated by MTT, Ki-67 and Hoechst 33258/PI double staining. The migratory and invasive abilities of HepG2 cells were measured by wound-healing and transwell assays. Pathological changes of tumor tissue were observed by HE staining and IHC methods. The expression levels of protein were detected using Western Blot analysis. Results: The results showed that Dulcitol inhibited HepG2 cells proliferation by down-regulating the protein expression of SIRT1, Bcl-2, along with up-regulating p53, acetylated-p53 (K382), cleaved-caspase9, cleaved-caspase3, Bax, and cytochrome c in a dose-dependent manner. Furthermore, Dulcitol surpressed the migration and invasion of HepG2 cells through decreasing the levels of MMP-2, uPA and MMP-9 and increasing E-cadherin associated with tumor invasion. In vivo, Dulcitol distinctly inhibited the growth of HepG2 cancer xenograft tumors via inhibiting SIRT1/p53 pathway. Conclusions: Our findings suggested that Dulcitol acted as a SIRT1 inhibitor, inducing apoptosis and inhibiting proliferation, migration and invasion of HepG2 cells and its modulatory mechanism seemed to be associated with regulation of MMPs, SIRT1/p53 pathways.