BCL2 and breast cancer: One study testing ABT-263, Bcl-2 and Bcl-xl selective inhibitors in a panel of breast cancer, non-small lung cancer and ovarian cancer cell lines, showed that only ABT-263 and the Bcl-xl selective inhibitors where able to induce sensitization to docetaxel, indicating that Bcl-xl is the most important protein causing chemo resistance20.