ABSTRACT
Objective To investigate the relationship between promoter hypermethylation of secreted frizzled-related protein (SFRP) gene and acute leukemia (AL). Methods We examined the promoter methylation starus of SFRP1, 2, 4 and 5 in primary or relapsed AL patients, cell lines ( HL60,NB4, Molt-4 and Jurkat) and peripheral blood mononuclear cells from healthy people with methylationspecific PCR (MSP). Results None of the normal mononuclear cells showed methylation of any SFRP genes. The frequencies of aberrant methylation among the samples were 33.9% (20/59) for SFRP1,23.7%(14/59) for SFRP2, 6. 8% (4/59) for SFRP4 and 10. 2% (6/59) for SFRP5 in acute myelocytic leukemia (AML), and 39.3% (11/28) for SFRP1, 28.6% (8/28) for SFRP2, 25.0% (7/28) for SFRP4 and 32. 1% (9/28) for SFRP5 in acute lymphoblastic leukemia (ALL). Hypermethylation of SFRP1, 2, 5genes were present in the 4 AL cell lines. SFRP4 was methylated in NB4, Molt-4 and Jurkat cell lines.However, methylation and unmethylation of SFRP4 were both detected in HL60. Conclusions Hypermethylation of SFRP genes is a common event in the evolution of AL. Methylation of SFRP genes might serve as potential independent biomarkers for early detection of AL.
ABSTRACT
Objective To establish and evaluate a diagnostic technique based on the AllGlo~(TM) probe for the invasive aspergillosis. Methods With the self-designed AllGlo~(TM) probes and primers and the standards, two standard curves of the real-time PCR based on AllGlo~(TM) probes were established respectively for A. flaws and A. fumigatus,then its specificity, sensitivity and reproducibility were evaluated respectively. Results The findings indicated that the standard curve of A. flavus was Y = - 3. 003X + 36. 825, and A. fumigatus' was Y = - 3. 052X + 38.016, and their interassay coefficient of variation respectively were 15.60% and 12. 94% , suggesting a good reproducibility. The lowest spore concentration they could be detected was 10 CFU/ml, which equated to 100-1000 copies of internal transcribed spacer (ITS)2 genes, suggesting a good sensibility. They didn't have cross-positive reaction with other fungus, human genome and bacteria, which indicated a good specificity. Conclusion The diagnostic technique based on the AllGlo?probe for the invasive aspergillosis possessed a good sensitivity, good specificity and deadly accuracy.
ABSTRACT
Objective To investigate the inhibition of proliferation and the regulation of histone acetylation modification in Jurkat cells treated by sodium valproate(VPA). Methods Jurkat cells were treated with VPA.Cell proliferation was determined by CCK-8 assay, and cell cycle were analyzed by flow cytometry (FCM). mRNA of HDAC1 was detected by semi-quantitative RT-PCR, and protein expression of HDAC1 and acetylation of histone H3, H4 was examined by Western blotting. Results VPA inhibited the proliferation of Jurkat cells in concentration-and time-dependent manners. After exposure to VPA in different concentrations for 48h,cell cycle was arrested obviously at G0/G1 phase (P <0.05), and with increasing concentration, the percentage of G0/G1 phase cells was increased and that of S phase were decreased. HDAC1 mRNA expression were inhibited with the increasing concentration of VPA. The protein level of HDAC1 was down-regulated, while acetylation of histone H3、H4 was up-regulated in Jurkat cells by VPA. Conclusion VPA can inhibit proliferation of Jurkat cells and induce G0/G1 phase arrest. The mechanism may be that VPA increase acetylation of histone H3/H4 by inhibiting expressions of HDAC1 gene.
ABSTRACT
Objective To observe the effects of triptolide(TPL) on the anti-oncogene-APC gene of acute lymphoblastic leukemia cell line Jurkat in vitro. Methods The effects of TPL on proliferation Jurkat cells were assayed by using cell culture, MTT. The effects of TPL on APC gene of Jurkat cells were analyzed by nested methylation specific PCR and RT-PCR. The effects of TPL on the proteinum expression of APC gene were detected by Western blotting analysis. Results Following the treatment of TPL, the cell proliferation rate was degraded as the treatment concentration increased and the culture time extended. The effects were dose and time-dependent. The 48 hour IC50 was 19.7 ng/ml. TPL can reverse hypermethylation of APC gene,and induce the expression of the mRNA and the proteinum. Conclusion Low dose TPL could depress the proliferation rate of Jurkat. The possible mechanism might be its reversing the hypermethylation of APC gene and activiting the expression of APC gene.