The analysis of co-occurrence of SOX11 with MEX3A and TUBB3 in breast cancers profiled in TCGA suggests that MEX3A is expressed predominantly in samples with higher levels of SOX11. The differences in cell growth observed both in vitro and in vivo with increasing levels of SOX11 suggest a dose-dependent regulation of SOX11 downstream targets and/or a possible post-translational modification. This evidence concerns the gene TUBB3 and breast carcinoma.