NCIt definition : An orally bioavailable inhibitor of the nuclear enzyme poly(ADP-ribose) polymerase
(PARP) 1 (PARP1) and 2 (PARP2), with potential antineoplastic activity. Upon oral
administration, simmiparib selectively binds to PARP and prevents PARP-mediated DNA
repair of breaks in single-stranded DNA via the base excision repair pathway. This
induces the accumulation of DNA strand breaks, promotes genomic instability, induces
G2/M arrest and leads to apoptosis. PARP is activated by single-strand DNA breaks
and catalyzes post-translational ADP-ribosylation of nuclear proteins, which signal
and recruit other proteins to repair damaged DNA.;