Cucurbitacin B has profound in vitro and in vivo antiproliferative effects against human pancreatic Y cells. It inhibited AKT signaling activation through up-regulation of PTEN. Cucurbitacin B is an effective inhibitor of HIF-1 and provide new perspectives into the mechanism of its anticancer activity. Cucurbitacin B inhibits proliferation and induces apoptosis via STAT3 pathway inhibition in A549 lung Y cells.