title: Mitochondria-dependent apoptosis induced by nanoscale hydroxyapatite in human gastric cancer SGC-7901 cells.
abstract: Nanoscale hydroxyapatite (nano-HAP) has been reported to exhibit anti-cancer effect on several human cancers, but the molecular mechanism of which remains unclear. The aim of this study was to explore the mechanisms by investigating the effects of nano-HAP on human gastric cancer SGC-7901 cells. Our results showed that nano-HAP significantly reduced cell viability, and induced apoptosis in SGC-7901 cells characterized by hypodiploid DNA contents, morphological changes and DNA fragmentation. The increase in apoptosis was accompanied with the increased expression of Bax, a pro-apoptotic protein, and decreased expression of Bcl-2, an anti-apoptotic protein, the decrease of mitochondrial membrane potential and the release of cytochrome c from mitochondria into cytosol. Furthermore, the activation of caspases-3, and -9, but not activation of caspases-8 was induced by nano-HAP. Z-VAD-fmk, a universal caspase inhibitor, dose-dependently inhibited nano-HAP-induced apoptosis. This study demonstrates that nano-HAP inhibits the proliferation of SGC-7901 cells by inducing apoptosis, and the apoptotic pathway of nano-HAP-induced apoptosis is mediated through the mitochondrial-dependent and caspase-dependent pathway.
authors.affiliation: Department of Gastroenterology, Zhongnan Hospital, Wuhan University, China.
authors.forename: Xiaojuan
authors.initials: X
authors.lastname: Chen
authors.forename: Changsheng
authors.initials: C
authors.lastname: Deng
authors.forename: Shengli
authors.initials: S
authors.lastname: Tang
authors.forename: Ming
authors.initials: M
authors.lastname: Zhang
mesh_terms: D000590:Amino Acid Chloromethyl Ketones / Q000494:pharmacology; D000970:Antineoplastic Agents / Q000737:chemistry / Q000494:pharmacology* / Q000627:therapeutic use; D017209:Apoptosis / Q000187:drug effects*; D061945:Caspase Inhibitors; D020169:Caspases / Q000378:metabolism; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D015853:Cysteine Proteinase Inhibitors / Q000494:pharmacology; D045304:Cytochromes c / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D017886:Durapatite / Q000737:chemistry / Q000494:pharmacology* / Q000627:therapeutic use; D004789:Enzyme Activation / Q000187:drug effects; D006801:Humans; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D008928:Mitochondria / Q000187:drug effects* / Q000378:metabolism; D053758:Nanoparticles; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D013274:Stomach Neoplasms / Q000188:drug therapy / Q000378:metabolism / Q000503:physiopathology*; D013997:Time Factors; D051028:bcl-2-Associated X Protein / Q000378:metabolism
chemical_list: D000590:Amino Acid Chloromethyl Ketones; D000970:Antineoplastic Agents; C494826:BAX protein, human; D061945:Caspase Inhibitors; D015853:Cysteine Proteinase Inhibitors; D019253:Proto-Oncogene Proteins c-bcl-2; D051028:bcl-2-Associated X Protein; C096713:benzyloxycarbonylvalyl-alanyl-aspartyl fluoromethyl ketone; D045304:Cytochromes c; D017886:Durapatite; D020169:Caspases