Phycocyanin inhibition of H460 cell proliferation and migration via down-regulation of IRS1 expression

Phycocyanin, a food colorant from marine algae, has been shown to inhibit proliferation and migration of non-small cell lung cancer (NSCLC) cells H460, leading to reduced colony formation．Transcriptomic analysis revealed significant down-regulation of insulin receptor substrate 1 (irs1) after phycocyanin treatment．H460 proliferation and migration was examined when IRS1 expression was down-regulated with small interfering RNA (siRNA)．MTT assay was used for cell proliferation, wound-healing assay for cell migration, colonogenic assay for colony formation, flow cytometry for cell cycle distribution．IRS1 expression was confirmed to be down-regulated after transfection with siRNA．Compared with controls, cell growth was decreased, cell migration and colony formation were inhibited, cell cycle was blocked to G1 phase．PI3K-AKT signaling was inhibited by phycocyanin．Transfection with siRNA-IRS1 led to PI3K-AKT signaling proteins to be down-regulated．It is concluded that inhibitory effect of phycocyanin on non-small cell lung cancer cells H460 may be related to reduced IRS1 expression and PI3K-AKT signaling．