The effect of MIEN1 in promoting invasion and migration in cancer stem cells.

Purpose MIEN1 (Migration and Invasion Enhancer 1 – MIEN1), located on chromosome 17q12, encodes a membrane-anchored protein that functions as an oncoprotein in several types of cancers (breast, prostate, oral and colorectal cancer), enhancing the biological processes of migration and invasion. The aim of this project is to evaluate the effect of MIEN1 on migration and invasion in Breast Cancer Stem Cells (BCSCs). Methods BCSCs were isolated from breast cancer cell line MDA MB 231, MDA MB 231 derivatives with varying levels of MIEN1 (A2, A10 and B7), MCF7 and a breast epithelial cell line MCF10A as control. Breast cancer cells were used for spheroid cultures for 21 days, which were used to isolate stem cells. ALDH (Aldehyde dehydrogenase) kit was used to isolate stem cells from spheroid cultures using FACS. Levels of MIEN1 protein will be evaluated by western blot. Results Spheroids with a dense core and loosely attached cells at the periphery were observed in ultra-low attachment 96 well plate after 21 days of seeding. BCSCs were isolated from spheroid cultures of MDA MB 231 and its derivatives A2, A10 and B7 using FACS and the data was analyzed using FlowJo software. MIEN1 protein levels will be checked in the isolated stem cell population using western blot. Conclusions Isolation of BCSCs from spheroid cultures yielded ~1% ALDH positive cells when 4.7x105 cells were used for sorting. Cells from 2-D cultures with more than 106 cells, grown in enhanced media, will be used for BCSC isolation.