PRKCD and neoplasm: Therefore, the ultimate effect of cell proliferation or apoptosis induction by PEP005 depends on the balance between the levels and activities of pro-apoptotic (PKCδ) and anti-apoptotic (PKCα and PKCε) isoforms of PKC as well as their crosstalk with different signaling pathways (MAPKs, NF-κB, and Akt) in each tumor B cell line.