STAT3 and breast cancer: For example, T. kirilowii tuber ethanol extract and cucurbitacin D (an active component in this extract) have been reported to inhibit cell growth and induce apoptosis by inhibiting STAT3 activity in breast cancer cells [19], and isoaurone, cucurbitacin B, and 6-(3-hydroxy-4-methoxystyryl)-4-methoxy-2Hpyran-2-one isolated from the methanol extract of T. kirilowii seeds were reported to potently inhibit HIF-1 and NF-κB activities [5].