Going from an in vitro breast cancer cell model using HMEC, MCF7 and MDA-MB-231 cells to clinical breast cancer samples, we could largely replicate findings concerning the up-regulation of both hnRNPA1 and CBX5 in carcinoma versus normal breast epithelial cells, de-coupling of hnRNAP1 and CBX5 expression in metastatic breast cancer cells, and the relative up-regulation of the STET transcript in metastatic breast cancer cells. The gene discussed is CBX5; the disease is breast cancer.