Antitumor effects of genipin: New and emerging insights from recent studies

Genipin, an aglycone derived from geniposide found in Gardenia jasminoides, is known to be an excellent natural cross-linker, strong apoptosis inducer, and antiviral agent. Although evidence suggests antiviral activity of genipin in several in vitro viral infection systems, there have been few literatures which review antitumor effects of genipin in a variety of in vitro/in vivo models of cancers yet. In this review, we present some of the latest findings in the studies of genipin focusing on antitumor effects and its mechanisms. In brief, genipin inhibits mitochondrial uncoupling protein 2 to increase accumulation of reactive oxygen species, leading to ROS/c-Jun N-terminal kinase-dependent apoptosis of cancer cells. Genipin also increase tissue inhibitors of metalloproteases (MMP), resulting to decrease activities of MMP-2 which plays a key role in metastasis of cancers. Genipin has shown a biphasic effects on cell death and survival in cancer cells as many other plant-derived phytochemicals do. Finally we discuss the potential of genipin as a promosing novel antitumor agent which could be applicable to chemotherapy and/or chemoprevention for cancers.