INS and cancer: It is important that medium should not be supplemented with FBS or any other serum but rather with factors enhancing ‘stemness’ features like basic fibroblast factor (bFGF) or epidermal growth factor (EGF) with hormone additives like insulin, hydrocortisone and progesterone depending on the cancer type as described before (Bielecka et al. 2016; Weiswald et al. 2015).