Geranylgeraniol Is a Potent Inducer of Apoptosis in Tumor Cells

We screened various isoprenoids to find inducers of apoptosis for human leukemia HL-60 cells, and found that GGO (geranylgeraniol) had the most potent apoptosis-inducing activity, as judged from DNA fragmentation in HL-60 cells. The apoptosis-inducing activity of GGO is concentration- and time-dependent. DNA synthesis by HL-60 cells was selectively inhibited on treatment with GGO. Besides HL-60 cells, apoptosis was induced by GGO in various tumor cell lines, including human myeloid multipotential leukemia K562, lymphoblastic leukemia Molt3, and colon adenocarcinoma COLO320 DM.