ABSTRACT
Objective To screen siRNAs that can effectively inhibit Apollon gene expression and determine the cellular functions of those siRNAs.Methods A chemical synthesis method was used to synthesize 3 siRNA sequences against different sites of Apollon.They were transfected into the human breast cancer MCF-7 cells by using Lipofectamine 2000.mRNA level of Apollon was determined by reverse transcription-polymerase chain reaction (RT-PCR).Cellular immunity fluorescence quantitative analysis combined with confocal laser technology was used to determine the protein level of Apollon.Methyl thiazolyl tetrazolium bromide (MTT) assay and flow cytometry were used to determine the effects of siRNA targeting Apollon on proliferation and apoptosis of MCF-7 cells,respectively.Results Three pairs of siRNA could significantly inhibit Apollon mRNA expression,at the inhibition rates of (36.201±11.629) ％,(67.308±7.686) ％and (47.123±12.000) ％,respectively (P ＜ 0.05).After tranfection by siRNA2,Apollon protein fluorescence intensity was (14.97±2.08) ％ compared with control cells.The cell proliferation MCF-7 was inhibited by (73.361±2.118) ％and apoptosis was increased by (28.793±0.743) ％.Conclusions Screened siRNA2 effectively silences Apollon gene expression,effectively inhibits the proliferation and increases the apoptosis of MCF-7 cells.This provids the foundation for its clinical application in cancer therapy.
ABSTRACT
Background and purpose:Apollon gene is highly expressed in leukemia and other tumors. The study aimed to discuss whether RNAi technology can reverse multidrug resistance of chronic myeloid leukemia cell line K562 through constructing a eukaryotic vector of short hairpin RNA (shRNA) targeting at Apollon gene. Methods:The eukaryotic vector pGPHI-GFP-Neo-Apollon with shRNA targeting at Apollon gene was constructed and then transfected into K562 cells by LipofectamineTM2000, and G418 pressure selection. Reverse transcription-polymerase chain reaction (RT-PCR) and immunolfuorescence were used to detect the expression of Apollon mRNA and protein after Apollon was transfected stably in K562 cells. The changes of sensitivity of K562 cells to leurocristine (VCR) and etoposide (VP16) after transfection with shRNA-Apollon were detected by MTT method, and the apoptosis rate was detected by flow cytometry. Results: pGPHI-GFP-Neo-Apollon carrier was constructed successfully and expressed stably in K562 cells, and after G418 screening, it silenced Apollon mRNA and protein expression effectively. According to the result of MTT, the sensitivity of K562 cells to VCR and VP16 increased significantly in the group of gene interference, with half of its inhibition concentration (half-inhibitory, IC50) value signiifcantly lower than the control group (P0.05). Conclusion:pGPHI-GFP-Neo-Apollon carrier can enhance the abilities of VCR and VP16 to induce the apoptosis of K562 cells, namely an increase of sensitivity to these chemotherapeutics in K562 cells, it is hinted that RNA interference targeting Apollon gene may reverse the multidrug resistance of leukemia cells in some degree.
ABSTRACT
HOXB gene is a homeobox gene family member and plays an important role in hematopoietic regulation.The abnormal expression is involved in leukemia.High expression of different subtypes influence leukemia progress and phenotype,and are closely related with leukemia treatment and prognosis.The higher the expression level is,the worse prognosis is.Many methods such as transgenic,inhibit of P21,combined with cytokine or MS-5 cell lines( all-trans retinoic acid) at the genetic level can reveal the pathogenesis of leukemi a and provide theoretical basis for treatment and prognosis.