Effect of curcumin on miRNA expression in human Y79 retinoblastoma cells

Retinoblastoma (RB) is the most common intraocular malignancy in children. Deregulation of several miRNAs has been identified in RB, suggesting a potential role in tumorigenesis. Recent evidence suggests that many dietary components like folate, retinoids and curcumin act as potential anticancer/antiproliferative agents by regulating the expression of miRNA. In this study, we investigated the effect of phenolic compound curcumin on miRNA expression in Y79 RB cells.

We analyzed the expression profile of miRNA by microarray analysis and quantitative real-time polymerase chain reaction (qRT-PCR) in curcumin-treated Y79 RB cells. Transfection of miR-22 was performed using Lipofectamine 2000. Cell viability, in vitro scratch migration assay, prediction of miRNA targets and Western blot analysis were performed to determine the biological function of miR-22 in Y79 RB cells.

In Y79 RB cells treated with curcumin, 5 human miRNAs were upregulated and 16 were downregulated as detected with the miRNA microarray analysis. miR-22, a tumor-suppressor miRNA was one of the miRNA which was upregulated by curcumin. Transfected miR-22 Y79 cells inhibited the cell proliferation and reduced the migration, and erythoblastic leukemia viral oncogene homolog 3 (Erbb3) was confirmed to be the target gene of miR-22.

These observations suggest that curcumin modulate the miRNA expression profile, thereby exerting its anticancer effects on RB cells.