The anti-growth effects of hydroxysafflor yellow A on esophageal squamous cell carcinoma-resistant KYSE150/5-FU cells and its mechanisms

AimTo determine the effect of hydroxysafflower yellow A (HSYA) on tumor cell growth, migration and invasion, and elucidate the underlying molecular mechanisms in esophageal squamous cell carcinoma-resistant KYSE150/5-FU cells.MethodsCCK-8 and colony formation assay were used to the effects of HSYA on KYSE150/5-FU cell growth. Transwell migration and invasion assay were employed to detect the effect of HSYA on the tumor cell migration and invasion. RT-qPCR was performed to detect the mRNA expression of drug-resistance gene including ID1 and ABCB1. Western blotting was utilized to detect the protein levels of PAK1 (p21-activated kinase 1), ERK1/2 (extracellular signal-regulated kinase 1/2) and p-ERK1/2 (T202/Y204). Nude mouse transplant tumor model was established to validate the effect of HSYA on KYSE150/5-FU cells in vivo.ResultsHSYA suppressed the growth of KYSE150/5-FU cells in a dose- and time-dependent manner. HSYA also remarkably reduced the number of colonies in KYSE150/5-FU cells. In addition, HSYA significantly inhibited the migration and invasion of KYSE150/5-FU cells. More importantly, the in vivo experimental results demonstrated that HSYA exerted a substantial inhibitory effect on the growth of KYSE150/5-FU cell in nude mice. Compared with KYSE150 cells, the mRNA levels of drug resistance genes ID1 and ABCB1, as well as the protein levels of PAK1 and p-ERK1/2(T202/Y204), were obviously upregulated in KYSE150/5-FU cells; while the levels of ID1, ABCB1, PAK1 and p-ERK1/2(T202/Y204) were greatly downregulated by HSYA in a concentration dependent manner in KYSE150/5-FU cells. The animal experiments shown that HSYA inhibited the growth of KYSE150/5-FU cells in nude mice and downregulated the expression of ID1, ABCB1, PAK1 and pERK1/2 (T202/Y204) in tumor tissues. Molecular docking experiments revealed that HSYA bound to the active site of PAK1 protein to exert its inhibitory effect.ConclusionHSYA suppresses the growth, migration and invasion via downregulating PAK1/ERK signaling pathway in KYSE150/5-FU cells.