miR-200c-3p is demonstrated to play the role of tumour suppressor in different tumours. However, the miR-200c-3p biological function in normal fibroblast (NF) and cancer-associated fibroblast (CAF) remains unclear. This investigation aims to study the regulatory role of miR-200c-3p in the secretion of Interleukin-2 (IL-2) in CAF and NF. CAFs and NFs were isolated from tumour and normal tissue specimens respectively. Immunocytochemistry was used to confirm the presence of a fibroblast specific marker, alpha-actin smooth muscle, in NFs and CAFs. NF and CAF were transfected with scramble and miR-200c-3p utilizing the lipofectamine 2000 reagent. The protein levels of IL-2 were measured in CAFs, NFs, and transfected groups with miR-200c-3p and scrambled using an IL-2 enzyme-linked immunoassay kit. miR-200c decreased secretion of IL-2 in transfected CAF and NF compared to controls. Results elucidated that transfection of MiR-200c-3p can decrease the IL-2 secretion and consequently reduce IL-induced tumourigenic manner in the CAF.

BackgroundThe most common malignancy is breast cancer, among women in the world. Triple-negative breast cancer (TNBC) is the most aggressive subtype of breast cancer. Cancer associated fibroblasts (CAFs) play a critical role to support tumor cells in all aspect of cancer development such as cell proliferation, migration and angiogenesis. MiRNAs are one of the regulatory molecules that regulate the genes contributing to cell growth, differentiation, migration and apoptosis. Based on other studies, miR-200c, as a tumor suppressor, has low expression levels in cancer associated fibroblasts. In this investigation, effect of miR-200c overexpression was evaluated on proliferation, migration and angiogenesis of TNBC cells. MethodsThe fibroblasts were isolated from normal and cancer breast tissue. MiR-200c expression was assessed using RT PCR in cancer associated fibroblasts (CAFs) and normal fibrobalasts (NFs) and then, were transfected using miR-200c. Finally, its effect on proliferation, migration and angiogenesis of TNBC cells were evaluated. ResultsOur results confirm that in presence of miR-200c transfected fibroblasts, the proliferation, migration and angiogenesis of cancer cells significantly decreased. This effect may be due to the reduction of growth factors provided by CAFs after miRNAs dysregulation. ConclusionThese results suggest miR-200c act as an effective tumor suppressor in many aspects of TNBC cancer development and can be regarded as a potential therapeutic tool for breast cancer in the future.

Cancer-associated fibroblasts (CAFs) play a critical role in supporting tumour cells in all aspects of cancer development, such as cell proliferation, migration and angiogenesis. MicroRNAs (miRNAs) as regulatory molecules regulate the genes contributing to cell growth, differentiation, migration and apoptosis. According to the literature, miR-200c, as a tumour suppressor, has low expression levels in CAFs. In this investigation, the effect of miR-200c overexpression was evaluated on proliferation, migration and angiogenesis of triple-negative breast cancer (TNBC) cells. The fibroblasts were isolated from normal and cancerous breast tissue. MiR-200c expression was assessed using real-time polymerase chain reaction in cancer-associated and normal fibroblasts. Then, the effect of miR-200c transfection on proliferation, migration and angiogenesis of TNBC cells was evaluated. Our results confirm that in the presence of miR-200c transfected fibroblasts, the proliferation, migration and angiogenesis of cancer cells significantly decreased. This effect could be attributed to the reduction of growth factors provided by cancer-associated fibroblasts after miRNA dysregulation. These results propose that miR-200c acts as an effective tumour suppressor in many aspects of TNBC development and can be considered a potential therapeutic tool for breast cancer in the next generation of pharmaceutics.