In Vitro: PARP/PI3K-IN-1 (compound 15; 1 μM; 72 hours) leads to a significant increase in cell apoptosis. PARP/PI3K-IN-1 (1 μM; 72 hours) reduces the autophosphorylation levels of AKT and S6 while increases the autophosphorylation level of ERK after treating cells, indicating that it can inhibit the PI3K pathway and activate the ERK pathway. PARP/PI3K-IN-1 (1 μM) displays a strong capability to downregulate the expression of BRCA1/2 at the mRNA level in MDA-MB-468 cancer cells. PARP/PI3K-IN-1 not only shows significant inhibitory activity against BRCA-deficient cells HCC1937 and HCT116, but also displays potent anti-proliferative activity against BRCA-proficient cells MDA-MB-231 and MDA-MB-468.
In Vivo: PARP/PI3K-IN-1 (i.p.; 50 mg/kg; twice daily (BID) for 34 consecutive days) significantly suppresses the tumor growth.