PARP1 expression is increased in different cancer types, particularly at advanced stages (Ossovskaya et al. 2010; Domagala et al. 2011; Mascolo et al. 2012; Bi et al. 2013; Bieche et al. 2013; Gan et al. 2013; Salemi et al. 2013; Dziaman et al. 2014; Park et al. 2015; Zhai et al. 2015; Li et al. 2016; Hou et al. 2018), and in some cases correlates positively with the cytotoxic effects of PARP inhibition (Byers et al. 2012; Kukolj et al. 2017). Here, PARP1 is linked to cancer.