JOURNAL OF ISTANBUL FACULTY OF MEDICINE-ISTANBUL TIP FAKULTESI DERGISI, no.3, pp.235-245, 2024 (ESCI)
Objective: Curcumin is considered an epigenetic regulator with anticancer effects. The micro-RNA (miRNA) miR-145-5p is a tumor suppressor that shows low expression levels in various cancers, including breast cancer (BC). This study aims to investigate whether curcumin inhibits MCF-7 human BC cell line proliferation and migration by regulating miR-145-5p and its possible target genes. Material and Method: MCF-7 cells were treated with curcumin and its solvent control. Additionally, cells were transfected with an miR-145-5p mimic and a non-targeting miRNA mimic. Cell viability was then evaluated, and the scratch wound assay was used to assess cell migration. The study predicts the miR-1455p putative target genes by searching for overlapping genes in the miRNet and miRTarBase v8 databases via the overexpressed genes in the BC tissue samples in the Cancer Genome Atlas (TCGA) datasets. Expression levels of miR-145-5p and the selected genes were detected using the quantitative real-time polymerase chain reaction (qRT-PCR). The 2 -Delta Delta Ct method was used for the quantification analysis, with p<0.05 being considered statistically significant. Result: Curcumin treatment and overexpression of miR-1455p via the transfection of an miR-145-5p mimic significantly decreased the proliferation and migration of MCF-7 cells. Moreover, curcumin treatment significantly increased the expression of miR-145-5p. The possible target genes of miR-1455p (i.e., MCM2, MMP1, MMP9, EEF1A2) ) were downregulated in curcumin-treated MCF-7 cells. Additionally, miR-145-5p mimictransfected cells showed low expression levels of the MCM2, MMP1, , and MMP9 genes. Conclusion: Curcumin inhibits the proliferation and migration of MCF-7 cells by acting on miR-145-5p and its possible target genes.