Background: Breast cancer is the most common cancer types among women. Recent researches have focused on determining the efficiency of alternative molecules and miRNAs in breast cancer treatment. The aim of this study was to determine the effect of usnic acid response-miR-185-5p on proliferation in the breast cancer cell and to determine its relationship with apoptosis pathway. Methods: The cell proliferation and cell apoptosis rate were significantly increased following the ectopic expression of miR-185-5p in BT-474 cells. Furthermore, the results of cell cycle assay performed by flow cytometry revealed that the transfection with miR-185-5p induced G1/S phase arrest. The apoptosis-related genes expression analysis was performed by qRT-PCR and the direct target of miR-185-5p in BT-474 cells was identified by western blot and luciferase reporter assay. Results: Our data showed that miR-185-5p can cause significant changes in apoptosis-related genes expression levels, suggesting that cell proliferation was suppressed by miR-185-5p via inducing apoptosis in breast cancer cells. According to western blot results, miR-185-5p lead to decrease BCL2 protein level in BT-474 cells and direct target of miR-185-5p was identified as BCL by luciferase reporter assay. Conclusion: This study revealed that miR-185-5p may be an effective agent in the treatment of breast cancer.

Five species of lichens, Ramalina fastigiata. (Pers.) Ach., Ramalina capitata., (Ach.) Nyl., Ramaliana polymorpha. (Lilj.) Ach., Ramalina pollinaria. (Westr.) Ach., and Ramalina fraxinea. (L.) Ach., belonging to family Ramalinacae. were collected from middle Anatolia, Ankara, Antalya, Karabük, and Kayseri in Turkey. Their usnic acid amounts were determined by HPLC in acetone extracts. Furthermore, antimicrobial activities of these extracts were determined against Escherichia coli. (ATCC 35218), Enterococcus faecalis. (RSKK 508), Proteus mirabilis. (Pasteur Ens. 235), Staphylococcus aureus., Bacillus subtilis., and Bacillus megaterium.. It was observed that, as the usnic acid amount increased, the antimicrobial activities were increased. Results pointed out that usnic acid contents of Ramalina. species varied between 0.13% and 3.23% dry weight.