Curcumin as an Adjunct Therapy and microRNA Modulator in Breast Cancer

Background: Pathogenesis of breast cancer is paralleled by distinct alterations in the expression profile of several microRNAs (miRNAs). Recent studies have shown that miRNAs can serve as diagnostic and prognostic markers, and also as therapeutic targets in breast cancer. Curcumin is a biologically active dietary polyphenol that has emerged with strong anti-tumor properties that are also documented in breast cancer. Methods: A multi-database electronic search was performed to provide an overview of curcumin as an adjunct therapy and miRNA modulator in breast cancer and highlight the significance of observations for the treatment of cancer therapies. Results: The putative anti-tumor properties of curcumin are mediated by diverse mechanisms including inhibition of cell proliferation, metastasis, migration, invasion and angiogenesis, and induction of G2/M cell cycle arrest, apoptosis and paraptosis. Recent evidence implies that curcumin can interact with several oncogenic and tumorsuppressive miRNAs involved in different stages of breast cancer. In this context, up-regulation of miR181b, miR-34a, miR-16, miR-15a and miR-146b-5p, and down-regulation of miR-19a and miR-19b have been shown following the treatment of several breast cancer cell lines with curcumin. These effects lead to the suppression of tumorigenesis and metastasis, and induction of apoptosis. Conclusion: Curcumin appears as an important miRNA modulator in breast cancer. However, further investigations are warranted to elucidate the impact of curcumin on miRNA transcriptome profile of breast cancer and the resulting impact of experimental models.