Due to the role of NCS‐1 as a positive regulator of IP3Rs (Boehmerle et al., 2007; Schlecker et al., 2006) and the lack of studies defining a role for NCS‐1 in Ca2+ signaling in breast cancer cells, we assessed two possible consequences of NCS‐1 silencing in the GCaMP6m‐MDA‐MB‐231 breast cancer cell line. The gene discussed is NCS1; the disease is breast cancer.