Later, work in basic oncology has revealed that PDE3 inhibitors including zardaverine, quazinone, and anagrelide can induce apoptosis in tumor cell types that feature PDE3A expression (e.g., HeLa, H4, MCF7, EKVX, A2058, SK-MEL-3, HCC, ERMS, A2058, COLO741, H2122, and GIST882 cells)11–13,15,17–19,21–23. Here, PDE3A is linked to neoplasm.