The significant basal expression level of CSRP2 in invasive normoxic cells (Fig. 1) is not contradictory with the role of CSRP2 in mediating the pro-invasive effects of hypoxia, and shows that hypoxia operates in breast cancer cells by up-regulating an actin regulatory protein that is also required for normoxic invasion. This evidence concerns the gene CSRP2 and breast carcinoma.