Since the seminal description of Janz et al. [1] that high YB-1 expression levels in breast cancer and surrounding tissues are indicative for poor outcome, follow-up studies have extended these findings to larger cohorts and other cancer entities, including non-small cell lung cancer [2], ovarian cancer [3], prostate cancer [4], and synovial sarcoma [5]. Here, YBX1 is linked to breast cancer.