Recently we have shown that 7-MG inhibits DNA repair enzymes poly(ADP-ribose) polymerases, PARP1 and PARP2, in a competitive manner and accelerates apoptotic death of cancer cells induced by cisplatin and doxorubicin (Nilov et al., 2016; Nilov et al., 2018a; Nilov et al., 2020a). Here, PARP1 is linked to cancer.