PARP1 and cancer: This data may be cancer-type specific, since this study is the first one to shed light on the potential dual effect of PARP-1 in CRC, and the previous PARP-1 works have been mainly focused on the fact of PARP-1 being overexpressed in CSCs, discussed previously, and in the combination of PARP-1 inhibitors with other therapies [12,40].