Quercetin Change the Exosome Secretion and Total miRNA Concentration in Primary (Colo320) and Metastatic (Colo741) Colon Cancer Cell Lines

Objective: Quercetin, which is considered a potential anti-cancer agent in the prevention of colon cancer, is one of its natural polyphenolic compounds. Extracellular vesicles, such as exosomes, secreted from cells and their components contribute to cellular behavioral characteristics by transporting proteins or miRNAs. In this study, we aimed to determine the cytotoxicity of Dicer, Ago2, eIF2 alpha CD9 and CD63 and their effects on exosomal miRNA secretion and expression in Colo320 and Colo741 colon cancer cell lines applied quercetin. Methods: The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) assay was used to analyze the cytotoxicity of quercetin. MTT analysis is a colorimetric analysis method applied to measure the metabolic activity of cells. The absorbance was measured at 570 nm by a spectrophotometer. Besides that, the indirect immunoperoxidase staining was used for the distribution of Dicer, Ago2, eIF2 alpha, CD9, and CD63 in Colo320 and Colo741. Total miRNA in exosome was determined with miRCURYTM Kit. Results: The immunoreactivities of eIF2 alpha and CD9 significantly differed compared to the Colo741 control group after quercetin application. In addition, exosomal miRNA concentrations were higher in both quercetin applied-Colo320 and Colo741 cells. Conclusion: We concluded that quercetin triggered exosomal secretion in Colo320 and Colo741 cells. However, exosomal component should be evaluated in future investigations to understand the quercetin role in primary and metastatic colon adenocarcinoma cells.