PIK3CA and small cell lung carcinoma: To identify pathways modulated by PARP inhibition, we performed reverse phase protein array (RPPA) which measured changes in 137 total and phosphorylated proteins in key oncogenic pathways including PI3K, MEK and DNA repair in a panel of SCLC cell lines treated with either vehicle or one the PARP inhibitors olaparib (AZD2281), rucaparib (CO-338, AG 014699), or talazoparib (BMN 673) for 24 hours.