title: [Proliferative and invasive effects of inhibitors of kinase 4(P15(ink4b) and P16(ink4a)/CDKN2) gene activation on RKO human colorectal cancer cells].
abstract: OBJECTIVE
  To explore the proliferation and invasive effects of inhibitors of kinase 4(INK4)(P15(ink4b) and P16(ink4a)/CDKN2) gene protein activation on RKO human colorectal cell in vivo and in vitro.
  
  
  METHODS
  RKO human colorectal cell line was exposed to the specific DNA methyltransferase inhibitor 5-Aza-CdR and INK4(P15(ink4b) and P16(ink4a)/CDKN2) protein expression was detected by Western blotting. Soft agar cloning experiment and Transwell chamber assay were used to detect the proliferative and invasive ability in vitro. Tumorigenicity in nude mice was analyzed in vivo.
  
  
  RESULTS
  INK4(P15(ink4b) and P16(ink4a)/CDKN2) protein expression of RKO human colorectal cells after exposure to 1×10(-7), 5×10(-7) and 1×10(-6) mol/L 5-Aza-CdR concentrations(A, B, C groups) were 1.13, 1.38, 1.92 folds and 1.11, 1.45, 2.14 folds compared to positive control group respectively. Soft agar cloning experiment showed the number of cell colony significantly decreased from 36.8±5.1(positive control group) to 32.4±7.2, 21.3±5.4 and 19.5±6.4 (3 experiment groups, all P<0.05) respectively. Transwell chamber assay showed that migrated cell number in positive control group(67.4±7.2) was significantly higher than those of 3 experimental groups(35.3±4.6, 29.5±7.3 and 25.3±6.2, respectively). The tumor volume of metastasis model in nude mice was inhibited in experimental groups, but not significantly lower compared to control group (P>0.05). There were significant differences of tumor weight and inhibition rate between control group and 3 experimental groups in nude mice respectively(all P<0.01).
  
  
  CONCLUSIONS
  INK4(P15(ink4b) and P16(ink4a)/CDKN2) protein activation can inhibit tumor proliferation, migration and suppress the tumor formation ability.
authors: Cancer Institute, Zhejiang University School of Medicine, Hangzhou 310009, China. zhengshu@zju.edu.cn.
authors: Xiaoming
authors: X
authors: Fang
authors: Zhaohui
authors: Z
authors: Jiang
authors: Jiaping
authors: J
authors: Peng
authors: Ning
authors: N
authors: Yao
authors: Xudong
authors: X
authors: Fang
authors: Shu
authors: S
authors: Zheng
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D015179:Colorectal Neoplasms / Q000378:metabolism / Q000473:pathology*; D050762:Cyclin-Dependent Kinase Inhibitor p15 / Q000235:genetics / Q000378:metabolism*; D019941:Cyclin-Dependent Kinase Inhibitor p16 / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D051379:Mice; D008807:Mice, Inbred BALB C; D009362:Neoplasm Metastasis; D009368:Neoplasm Transplantation; D015533:Transcriptional Activation
chemical_list: D050762:Cyclin-Dependent Kinase Inhibitor p15; D019941:Cyclin-Dependent Kinase Inhibitor p16