Podocarpusflavone A is a DNA topoisomerase I and STAT3 inhibitor, a flavonoid chemically inactive isolated from the endemic Taiwanese plant, Luo Han Guo, with potential antileishmanial activity and antitumor activity.Podocarpusflavone A, inhibits the cell growth of cutaneous dermal melanoma.

Podocarpusflavone A showed significant inhibition against KB, DLD, HEp-2, MCF-7 tumour cell lines (ED50 4.56-16.24 μg/mL). It induced cell apoptosis in MCF-7 mainly via sub-G1/S phase arrest. PF (40 ug/mL, 24 hours) induced a significant increase in cell death and growth arrest in the S phase by about 10-fold compared to the control group;[1]Podocarpusflavone A (0,5,10,20 μM) treatment of four melanoma cell lines (A375, Malme-3M, SK-MEL-1, and SK-MEL5) for 24 h significantly inhibited p-STAT3 levels, but not total STAT3 protein levels, in all cell lines tested. In addition, a dose-dependent inhibition of p-STAT3 expression was observed in both A375 and SK-MEL-1 cells and the IC50 values were approximately 10 μM for both A375 and SK-MEL-1 cells.[2]

Podocarpusflavone A was administered daily to A375 cell-derived xenograft mice (20, 40 mg/kg, po, for 21 days), and Podocarpusflavone A significantly suppressed tumor size and weight in xenograft mice. [2]