Although the molecular identity for the SK4‐controlled Ca2+ entry routes, that is the plasma membrane channels and store‐operated mechanisms in the PyMT and Her2/cNeu breast tumour cells, is ill‐defined, SK4 was previously colocalized or functionally linked to Ca2+ release‐activated Ca2+ (CRAC)‐like channels or TRP (transient receptor potential) family such as TRPV6, TRMP7 and TRMP3 in T lymphocytes, prostate cancer cells (Kuras et al., 2012; Lallet‐Daher et al., 2009) and MMTV‐PyMTtg/+ breast tumour cells (data not shown). Here, ERBB2 is linked to prostate cancer.