FIGURE 4.
MVs generated by transformed MEFs and aggressive breast cancer cells contain FAK. A, Western blotting analysis using FAK, Src, Paxillin, IκBα, and flotillin antibodies was performed on control MEFs and MEFs expressing onco-Dbl (WCL) as well as on the MVs these cells generated (MVs). Note that FAK is uniquely enriched in MVs derived from MEFs expressing onco-Dbl. B, the relative amounts of FAK detected in MVs generated by control (Uninduced) MEFs and MEFs expressing onco-Dbl (Onco-Dbl Induced) was determined across several experiments. The data represents the mean ± S.D. Student's t tests were performed. ***, p < 0.001. C, Western blotting analysis using FAK, IκBα, and flotillin antibodies was performed on uninduced MEFs and MEFs expressing onco-Dbl (WCL) as well as on the exosomes (Exosomes) and MVs (MVs) these cells generated. The blots were also probed with a CD-63 antibody, an exosome-specific marker. The vertical lines placed through the blots indicate where a small portion of each blot was deleted. Note that FAK is present only in the MVs from MEFs expressing onco-Dbl. D, Western blotting analysis using FAK, IκBα, HA, and flotillin antibodies was performed on normal MCF-10A mammary epithelial cells and MDAMB231, BT-549, and Hs-578T breast cancer cells (WCL) as well as on the MVs these various cell lines generated (MVs). The experiments in A–D were performed a minimum of three separate times, and molecular weight markers (in kilodaltons) are included along the right side of the blots in A, C, and D.