Staurosporine showed anti‐proliferative activity against healthy and cancer cell lines (MRC5 and A549) at a comparable level (2 and 3 ng/ml), which is in line with previous reports on staurosporine nonselective cytotoxicity via potent inhibition of protein kinases, especially tyrosine kinase (Manns et al., 2011; Nakano & Omura, 2009; Tamaoki et al., 1986). This evidence concerns the gene WEE1 and cancer.