Figure 2. Identification of membrane proteins involved in MGDAs-mediated enhancement of tumorigenic activity.
(a) Summary of cDNA microarray analyses. In all, 253 genes were identified with at least twofold upregulation in MDA-MB-231, MDA-MB-361 and MDA-MB-157 compared to MDA-MB-468 cells. (b) RNAi knockdown screening of candidate genes involved in MGDAs-mediated tumorigenic activity promotion in MDA-MB-157 cells by soft agar colony formation assay. shLacZ was used as a knockdown control. (c) Expression profiles of ARMCX1, ENPP1, FRMD5, GPC6, GPR126, RFTN1 and MCT2 in six different breast cancer cell lines. The experiment was performed in technical triplicate. (d) Western blot analyses reconfirmed the expression profiles of ENPP1 and MCT2 in breast cancer cell lines (no commercial workable ARMCX1 antibody was found). The experiment in b was performed in technical triplicate and repeated at least twice with similar results. Data show means±s.d. *P<0.05 (Student's t-test).