title: Cartilage polysaccharide induces apoptosis in human leukemia K562 cells.
abstract: In this study, we extracted a polysaccharide (short-chain polysaccharide [PS]) from porcine cartilage and examined its function in chronic myeloid leukaemia by using human K562 cells and mouse L1210 cells. Results of cell proliferation assay indicated that PS inhibited cancer cell growth at different concentrations, while it had little effect on normal cells. The presence of morphological aspects of apoptosis, such as nuclear shrinkage, was shown in H&E stained sections. The occurrence of PS-induced apoptosis was confirmed by TUNEL assay and cell cycle analysis. The results of immunofluorescent staining indicated the molecular mechanism underlying. Through interfering with the cell cycle of tumor cells, PS may induce apoptosis by downregulating the expression level of cyclin D1 and upregulating the level of p21 protein. Correlation analysis of apoptosis and MAPK suggested that inactivation of ERK was crucial for PS induced apoptosis, while JNK phosphorylation had a small effect and p38 was not involved. In vivo assay showed that PS inhibited L1210 cell growth in vivo and prolonged the life span of L1210-bearing mice. We conclude that PS is a polysaccharide with anticancer effects and induced apoptosis in human K562 cells.
authors.affiliation: Tianjin Key Laboratory of Food Nutrition and Safety, Institute of Food Engineering and Biotechnology, Tianjin University of Science and Technology, Tianjin, PR China. liuanjun666@yahoo.com.cn
authors.forename: A-J
authors.initials: AJ
authors.lastname: Liu
authors.forename: W
authors.initials: W
authors.lastname: Song
authors.forename: N
authors.initials: N
authors.lastname: Yang
authors.forename: Y-J
authors.initials: YJ
authors.lastname: Liu
authors.forename: G-R
authors.initials: GR
authors.lastname: Zhang
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D002356:Cartilage / Q000737:chemistry*; D002453:Cell Cycle / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D019938:Cyclin D1 / Q000378:metabolism; D050759:Cyclin-Dependent Kinase Inhibitor p21 / Q000378:metabolism; D005455:Fluorescent Antibody Technique; D006801:Humans; D020287:In Situ Nick-End Labeling; D020014:K562 Cells; D008297:Male; D051379:Mice; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D041681:NIH 3T3 Cells; D011134:Polysaccharides / Q000302:isolation & purification / Q000494:pharmacology*; D013194:Staining and Labeling; D013552:Swine
chemical_list: D050759:Cyclin-Dependent Kinase Inhibitor p21; D011134:Polysaccharides; D019938:Cyclin D1; D020928:Mitogen-Activated Protein Kinases