Intriguingly, inoculation of 100 soft either ALDH1+ or ALDH1− tumor cells were able to form a tumor in either NSG or WT mice; however, inoculation of 100 stiff ALDH1+ or ALDH1− tumor cells could not form a tumor, even in NSG mice (Figs 3B and EV3A). The gene discussed is ALDH1A1; the disease is neoplasm.