CDKL2 and invasive breast carcinoma: Due to lack of high quality CDKL2 antibody suitable for IHC staining on a large collection of human breast cancers specimens, we examined CDKL2 expression in 749 invasive breast cancers that were completed by TCGA [43] for analyses of RNA expression, copy number alteration and mutation (obtained from cBioPortal [44, 45]).