The human Lifeguard β-isoform was observed only in the patient primary cell cultures from invasive breast carcinoma with tumour grade III (cells appeared abnormal and tended to grow and spread more aggressively), but was not detected in the breast cancer cell lines and the liposarcoma carcinoma U2OS cell line (Fig. 2A). The gene discussed is FAIM2; the disease is invasive breast carcinoma.