Azar Sheikholeslami - Department of Animal Biology, Faculty of Biological Sciences, Kharazmi University, Tehran, Iran
Ehsan Arefian - Department of Microbiology, School of Biology, College of Science, University of Tehran, Tehran, Iran
Mohammad Nabiuni - Department of Cell and Molecular Biology, Faculty of Biological Sciences, Kharazmi University, Tehran, Iran

Introduction: Breast cancer is a heterogenous disease which is considered as the most common malignancy that develops in women worldwide. Despite all efforts on identifying cancer, there is no definite therapy yet and much more attempts in discovering cancer biology seems necessary. Immunology of tumors declares the relevance of immune system, chronic inflammation and cancer. Several studies indicate that the immune system may either aid in the prevention as well as the promotion of carcinogenesis. Materials and methods: Evaluating the progressing activity of immune system and inflammation in many diseases, we evaluated some molecular signaling pathways similar in inflammation and cancer and then detected the microRNAs which play pivotal roles in mediating these pathways. Using bioinformatic assays, signaling pathways common in both inflammation and cancer, and microRNAs mediating them were detected. miR-590 was selected and cloned into the pLenti-III-eGFP vector and then transfected into the breast cancer cell lines, MCF-7 and MDA-MB-231 using X-tremeGENE HP DNA Transfection Reagent. Results: 72 hours after transfection, the expression levels of miR-590 and the genes of JAK2, PI3K, MAPK1 and CREB were measured by Real-Time qRT-PCR. miR-590 showed over-expression as expected and the candidate genes were significantly down-regulated. Conclusion: miR-590 was selected as a microRNA which triggers and down-regulates the molecules and genes of signaling pathways similar in cancer and inflammation such as JAK2, PI3K, MAPK1 and CREB and a significant decrease was observed in these genes. The reduction occurred in these genes in breast cancer cell lines following the miRNA treatment is notable and in fact, more studies are needed to investigate the miR-590 function on breast cancer treatment.

Breast cancer, Inflammation, microRNAs, Transfection