Dysregulated expression of miR-642a-5p and its target receptor-interacting serine/threonine-protein kinase 1 contribute to the phycocyanin-mediated inhibitory function on non-small cell lung cancer

Abstract

Phycocyanin, a type of functional food additive, is shown to exert antineoplastic property in non-small cell lung cancer (NSCLC). Our previous work demonstrated that phycocyanin could suppress the viability of NSCLC cells via regulating receptor-interacting serine/threonine-protein kinase 1 (RIPK1), but the underlying mechanism remains unknown. Herein, a high-throughput miRNA sequencing method was employed to further explore miRNA variations for the first time. 43 down-regulated and 18 up-regulated miRNAs displayed differential expressions after phycocyanin exposure. Particularly, the expression of miR-642a-5p was significantly increased by phycocyanin. Dual-luciferase assay revealed that RIPK1 was a direct target of miR-642a-5p. siRNA knockdown RIPK1 expression and overexpression of miR-642a-5p both inhibited cell proliferation, colony formation and NF-κB activity, as well as induced apoptosis of NSCLC cells. The anticancer effect of phycocyanin was also validated in vivo using subcutaneous tumor formation model in nude mice. This study proposes that phycocyanin inhibits NSCLC cell activities through miR-642a-5p/RIPK1/NF-κB axis.

Keywords

• Cell activity
• miR-642a-5p
• Non-small cell lung cancer
• Phycocyanin
• Receptor-interacting serine/threonine-protein kinase 1