PUB045 Anti-Tumor Effect of Honokiol in Lung Squamous Cell Carcinoma

Abstract

Patients with lung squamous cell carcinoma (SCC) still benefit few from new therapies of lung cancer, and seeking for potential effective therapies is imperative. Honokiol (HNK) is a natural compound isolated from the magnolia plant with numerous pharmacological activities and exerts anticancer activity. Here, we demonstrated that the effect of HNK in lung SCC cells in vitro and related signaling mechanisms. Cell viability of human lung SCC cell lines NCI-H520 and SK-MES-1 exposed to HNK were measured by CCK-8. Flow cytometry was applied to identify the cellular apoptosis with HNK exposure of SCC cells compared to lung adenocarcinoma cells. Fibroblast growth factor(FGF)-2 expression of both SCC cells with HNK exposure were explored by quantitative real-time PCR. Furthermore, the effect of HNK on FGFR1 and signal pathways related to proliferation, apoptosis and cell cycle were detected by western blot. In two subpopulations of human lung SCC cells, NCI-H520 and SK-MES-1, HNK exposure remarkably inhibited the cell proliferation in both time-and dose-dependent manners. Compared to A549 cells, a more significant cell apoptosis was observed in NCI-H520 cells after HNK incubation. Next, real-time PCR analysis indicated that HNK down-regulated the expression of FGF2 in both NCI-H520 cells and SK-MES-1 cells in dose dependence. Meanwhile, HNK also obviously inhibited FGFR1 in both cell lines. Moreover, HNK exposure activated PARP and caused caspase-3 cleavage, suppressed cyclineD1 and ERK expression. These results broaden our understanding of the mechanisms on HNK effects in lung SCC, and reinforce the possibility of its potential anticancer benefit on SCC patients.