title: Apigenin sensitizes prostate cancer cells to Apo2L/TRAIL by targeting adenine nucleotide translocase-2.
abstract: Apo2 ligand (Apo2L)/tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a promising cancer therapeutic agent. Recombinant human Apo2L/TRAIL has been under clinical trials, whereas various kinds of malignant tumors have resistance to Apo2L/TRAIL. We and others have shown that several anticancer agents and flavonoids overcome resistance to Apo2L/TRAIL by upregulating death receptor 5 (DR5) in malignant tumor cells. However, the mechanisms by which these compounds induce DR5 expression remain unknown. Here we show that the dietary flavonoid apigenin binds and inhibits adenine nucleotide translocase-2 (ANT2), resulting in enhancement of Apo2L/TRAIL-induced apoptosis by upregulation of DR5. Apigenin and genistein, which are major flavonoids, enhanced Apo2L/TRAIL-induced apoptosis in cancer cells. Apigenin induced DR5 expression, but genistein did not. Using our method identifying the direct targets of flavonoids, we compared the binding proteins of apigenin with those of genistein. We discovered that ANT2 was a target of apigenin, but not genistein. Similarly to apigenin, knockdown of ANT2 enhanced Apo2L/TRAIL-induced apoptosis by upregulating DR5 expression at the post-transcriptional level. Moreover, silencing of ANT2 attenuated the enhancement of Apo2L/TRAIL-induced apoptosis by apigenin. These results suggest that apigenin upregulates DR5 and enhances Apo2L/TRAIL-induced apoptosis by binding and inhibiting ANT2. We propose that ANT2 inhibitors may contribute to Apo2L/TRAIL therapy.
authors: Department of Molecular-Targeting Cancer Prevention, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto, Japan.
authors: Masakatsu
authors: M
authors: Oishi
authors: Yosuke
authors: Y
authors: Iizumi
authors: Tomoyuki
authors: T
authors: Taniguchi
authors: Wakana
authors: W
authors: Goi
authors: Tsuneharu
authors: T
authors: Miki
authors: Toshiyuki
authors: T
authors: Sakai
mesh_terms: D033742:Adenine Nucleotide Translocator 2 / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D000970:Antineoplastic Agents / Q000494:pharmacology*; D047310:Apigenin / Q000737:chemistry / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D045744:Cell Line, Tumor / Q000187:drug effects; D004357:Drug Synergism; D055785:Gene Knockdown Techniques; D019833:Genistein / Q000737:chemistry; D006801:Humans; D008297:Male; D011471:Prostatic Neoplasms / Q000188:drug therapy*; D011485:Protein Binding; D034741:RNA, Small Interfering / Q000235:genetics; D053220:Receptors, TNF-Related Apoptosis-Inducing Ligand / Q000235:genetics / Q000378:metabolism; D053221:TNF-Related Apoptosis-Inducing Ligand / Q000494:pharmacology*; D015854:Up-Regulation / Q000187:drug effects
chemical_list: D033742:Adenine Nucleotide Translocator 2; D000970:Antineoplastic Agents; D034741:RNA, Small Interfering; D053220:Receptors, TNF-Related Apoptosis-Inducing Ligand; D053221:TNF-Related Apoptosis-Inducing Ligand; D047310:Apigenin; D019833:Genistein