T lymphocyte cell-derived nano-size exosome impedes the proliferation and induces apoptosis of breast cancer MDA-MB231 cells by negative regulation of microRNA27

Objective(s): To study the anti-cancer effects of the human immune T lymphocyte cell derived exosomes on breast cancer MDA-MB-231 cells in vitro.Methods: The exosome was isolated from human T cells and then characterized by western blotting respecting the expression of CD9, 63 and 81 and also morphological analysis by transmission electron microscopy (TEM). The anti-cancer effect of T cell derived exosome was assessed on MDA-MB-231 cell lines using MTT assay and Annexin V/PI staining and flowcytometry. The Bax, Bcl-2 and MiR-27a expression at mRNA levels also were estimated using real-time PCR.Results: Exosomes inhibited the proliferation of MDA-MB-231 cell lines within 12-72 hours of treatment. Also, intervention caused an increment the apoptosis levels of treated cells within 24 and 48 hours of treatment. Moreover, MiR-27a and Bcl-2 expression was decreased while up-regulating Bax expression in MDA-MB-231 cell lines.Conclusions: In this study, T cell derived exosome elicits a robust anti-cancer effect on MDA-MB-231 cells in part by improving Bax/Bcl-2 ratio and decreasing MiR-27a expression and triggering the apoptosis pathway.