Bmi-1-siRNA Regulates the Proliferation of K562 Leukemia Cells in vitro and in vivo by PTEN/pAKT Pathway / 中国实验血液学杂志

OBJECTIVE@#To investigate the effect of Bmi-1 gene silence on the proliferation ability of K562 cells in vitro and in vivo, and to explore the relation of molecular mechanism between proliferation ability of K562 cells in vitro and in vivo with PTEN/pAKT signaling pathway.@*METHODS@#The Bmi-1 small interference RNA (siRNA) sequences were transfected into K562 cells for decreasing Bmi-1 expression. The effect of Bmi-1 siRNA on the proliferation of K562 cells in vitro and in vivo was detected by MTT method and colony-forming test, the effect of Bmi-1 siRNA on the tumorogenicity of K562 cells was observed by subcutaneous inoculation of K562 cells, LY294002 and Bpv treated K562 cells in nude mice, the expression of Bmi-1, PTEN and pAKT proteins were detected by Western blot.@*RESULTS@#The Bmi-1 siRNA could inhibit the proliferation activity, colony-forming and tumor-forming abilities of K562 cells. After the silence of Bmi-1 gene, the PTEN expression in Bmi-1 gene-silenced group was significantly enhanced. While the pAKT expression in Bmi-1 gene-silenced group was significantly reduced; after the K562 cells were treated with LY294002 (an inhibitor of pAKT), the pAKT expression colony-forming and tumor forming abilities were reduced in comparison with untreated K562 cells; after the K562-S1 cells were treated with Bpv (an inhibitor of PTEN), the PTEN expression decreased, while the pAKT expression, colony forming and tumor-forming abilities were restored.@*CONCLUSION@#The Bmi-1 gene possibly involves in regulation of K562 proliferation in vivo and in vitro, the effect of PTEN/pAKT signaling pathway maybe one of molecular mechanisms mediating this regulation.

The Correlation between Vitamin D Receptor Gene Polymophism and Bone Metabolism Disorder in Children with Nephrotic Syndrome / 昆明医科大学学报

Objective To study the correlation between VDR gene polymorphism and the transformation of bone markers in children with nephrotic syndrome and to observe whether active intervention treatment of vitamin D with nephrotic syndrome is influenced by VDR gene polymorphism. Methods We used polymerase chain reaction restriction fragment length polymorphism (PCR- RFLP) technology to detect the VDR genotypes of 70 children with nephrotic syndrome (one group received hormone for 2 weeks and the other received no hormone therapy) . Then we detected bone metabolism index among patients with nephrotic syndrome and 30 normal children (control group) and compared the index between the two groups with and without hormone therapy.We divided 70 children with nephrotic syndrome into the AA+Aa genotype group and the aa genotype group to study the difference between various genotypes of bone metabolism indexes. After retesting bone metabolism index of those children receiving the same dose of calcitriol therapy after 2 weeks, we divided them into three groups AA genotype, Aa genotype and aa genotype to detect the changes of bone metabolism index in different genotypes.Results (1) The calcitonin and serum phosphorus of children with AA+Aa genotype were significantly lower than those of childrenwith aa genotype (P＜ 0.05);25 (OH) D3 of children with aa genotype was significantly lower than that of ones with Aa + Aa genotype (P＜ 0.05) . (2) The changes of bone metabolism index in children with nephrotic syndrome after receiving the same dose of calcitriol for 2 weeks: the calcitonin and 25 (OH) D3 in AA+Aa genotype group were significantly higher after treatment (P＜0.05) .Conclusions Vitamin D receptor gene ApaⅠpolymorphism may be a genetic susceptibility factors affecting bone metabolic abnormalities. AA and Aa genotype may be a protective factor of bone metabolic abnormalities.The AA+Aa genetype of Vitamin D receptor gene ApaⅠpolymorphism response to treatment of calcitriol is positive.