Background: Breast cancer is one of the most common types of cancers and the leading cause of death, especially in women throughout the world. Various genetics and environmental factors have been identified as a risk factor for development of breast cancer. Long non-coding RNAs (lncRNAs) have gained significant attention in recent years as new and crucial players in cancer development. Curcumin is a plant compound that has been shown to inhibit various aspects of cancer including apoptosis, inhibition of cell proliferation, invasion and angiogenesis.
Objectives: Elevated expression level of two lncRNAs, HULC and Linc-ROR, has been reported as contributing factor to the development of breast cancer. Therefore, we aimed to investigate the effect of nanocurcumin on expression levels of these genes. Besides, apoptotic effect of nanocurcumin on MCF7 cells was investigated.
Methods: MCF7 cells were exposed to various concentrations of nanocurcumin and their metabolic activity was measured by MTT assay. The level of HULC and Linc-ROR genes was evaluated by real-time PCR. Apoptosis was also determined by Annexin test.
Results: Twenty micromollar (m) concentrations of nanocurcumin significantly decreased the expression of HULC and Linc-ROR
genes (P < 0.05). These concentrations also led to significantly higher apoptosis rate in MCF7 cells (97%) compared to cell treated with curcumin.
Conclusions: Our findings suggested that nanocurcumin exhibits apoptotic effects on breast cancer MCF7 cells by reducing the expression level of two proto-oncogene lncRNAs, HULC and Linc-ROR, which are both involved in downregulation of p53.