The incubation of drug selective S1-M1-80 cancer cells (Figure 3A,D) and ABCG2 transfected HEK293/R2 cells (Figure 3B,F) with 6 μM of VKNG-1 for 72 h remarkably decreased the ABCG2 protein expression compared to cells incubated with vehicle. The gene discussed is ABCG2; the disease is cancer.