title: D-glucosamine inhibits proliferation of human cancer cells through inhibition of p70S6K.
abstract: Although D-glucosamine has been reported as an inhibitor of tumor growth both in vivo and in vitro, the mechanism for the anticancer effect of D-glucosamine is still unclear. Since there are several reports suggesting D-glucosamine inhibits protein synthesis, we examined whether D-glucosamine affects p70S6K activity, an important signaling molecule involved in protein translation. In the present study, we found D-glucosamine inhibited the activity of p70S6K and the proliferation of DU145 prostate cancer cells and MDA-MB-231 breast cancer cells. D-glucosamine decreased phosphorylation of p70S6K, and its downstream substrates RPS6, and eIF-4B, but not mTOR and 4EBP1 in DU145 cells, suggesting that D-glucosamine induced inhibition of p70S6K is not through the inhibition of mTOR. In addition, D-glucosamine enhanced the growth inhibitory effects of rapamycin, a specific inhibitor of mTOR. These findings suggest that D-glucosamine can inhibit growth of cancer cells through dephosphorylation of p70S6K.
authors.affiliation: Chronic Disease Research Center and Institute for Medical Science, School of Medicine, Keimyung University, Daegu 700-712, Republic of Korea.
authors.forename: Hyun-Ji
authors.initials: HJ
authors.lastname: Oh
authors.forename: Jason S
authors.initials: JS
authors.lastname: Lee
authors.forename: Dae-Kyu
authors.initials: DK
authors.lastname: Song
authors.forename: Dong-Hoon
authors.initials: DH
authors.lastname: Shin
authors.forename: Byeong-Churl
authors.initials: BC
authors.lastname: Jang
authors.forename: Seong-Il
authors.initials: SI
authors.lastname: Suh
authors.forename: Jong-Wook
authors.initials: JW
authors.lastname: Park
authors.forename: Min-Ho
authors.initials: MH
authors.lastname: Suh
authors.forename: Won-Ki
authors.initials: WK
authors.lastname: Baek
mesh_terms: D049109:Cell Proliferation / Q000187:drug effects*; D005944:Glucosamine / Q000494:pharmacology*; D006801:Humans; D009369:Neoplasms / Q000201:enzymology / Q000473:pathology*; D010766:Phosphorylation; D038762:Ribosomal Protein S6 Kinases, 70-kDa / Q000037:antagonists & inhibitors*; D020123:Sirolimus / Q000494:pharmacology
chemical_list: D038762:Ribosomal Protein S6 Kinases, 70-kDa; D005944:Glucosamine; D020123:Sirolimus