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ObjectiveTo explore the biological features of colorectal adenoma with chicken-skin mucosa ( CSM ) and its clinical significance.MethodsExpression of cell proliferation markers ( Ki-67 and COX-2) and apoptosis-related factors ( survivin and caspase-3) in normal colorectal mucosa,colorectal adenoma without CSM,colorectal adenoma with CSM and colorectal adenocarcinoma were detected by immunohistochemistry SP method and enzyme-linked immunosorbent assay (ELISA).ResultsImmunohistochemical results revealed a decreased trend in expressions of Ki-67 and COX-2 from colorectal adenocarcinoma through colorectal adenoma with and without CSM to normal colorectal mucosa,while the expressions of survivin and caspase-3 showed an increased trend.By ELISA,the expressions of Ki-67,COX-2,surviving and caspase-3 showed no significant difference (P ＞ 0.05 ) between colorectal adenoma with CSM and coloreetal adenocarcima,while these variables were significantly different (P ＜ 0.05) between coloreetal adenoma with and without CSM,so as well between normal colorectal mucosa and other 3 groups.ConclusionThe biological characteristics of colorectal adenoma with CSM are different from those without,showing an activated cell proliferation and inhibited cell apoptosis with increased carcinogenesis risk.
ABSTRACT
BACKGROUND:Little data have been available concerning the mechanism of drag resistance and anti-apoptosis in leukemic cells of leukemia children.The majority of studies focus on normal bone marrow mesenchymal stem cells (MSCs) and established stroma cells,but not interaction of MSCs and leukemic cells in leukemia children.OBJECTIVE:To explore the effect of MSCs in leukemia children on the proliferation and apoptosis of leukemic cell strain K562/AO_2.DESIGN,TIME AND SETTING:In vitro cytology experiment was performed at the laboratory of Department of Pediatrics,First Affiliated Hospital of Guangzhou Medical College from December 2007 to August 2008.MATERIALS:MSCs were provided by 30 leukemia children admitted to First Affiliated Hospital of Guangzhou Medical College,including 22 acute lymphoblastic leukemia and 8 acute myeloblastic leukemia.Written informed content was obtained from all families.K562/AO_2 was provided by Tianjin Institute of Hematopathy.METHODS:MSCs were isolated and cultured by Ficoll density gradient method.They were cultured in two conditions:the co-culture of MSCs and K562/AO_2 and K562/AO_2 suspension alone.In co-culture group,1×10~8 /L K562/AO_2 cells at log phase were added to confluent MSCs,and free floating K562/AO_2 cells were discarded after 24 hours.MAIN OUTCOME MEASURES:Effect of MSCs on the growth of K562/AO_2 cells was observed;effect of addamycln on K562/AO_2 cell apoptosis was detected by AnnexinV-FITC method.Cell cycle was determined by flow cytomtry,mdrl gene of K562/AO_2 cell was detected by Taqman-MGB probe real-time PCR.RESULTS:Compared with K562/AO_2 alone,the K562/AO_2 cell co-cultured with MSCs grew slower and the log phase of growth was not significant;the rate of apoptosis in earlier period was significantly decreased (P ＜ 0.05);co-cultured K562/AO_2 G_0-G_1 phase increased,but S phase decreased.No changes in mdr1 gene in cells were found between two culture conditions (P ＞ 0.05).CONCLUSION:In vitro cytology has demonstrated that leukemia children MSCs induce drug resistance of K562/AO_2 cells by changing K562/AO2 cell cycle through adhesion to avoid pro-apoptotic effect of drugs but not related with mdr1 gene.
ABSTRACT
Objective To investigate the effect of p15~(INK4B)(p15)gene transfection on the proliferation of pancreatic cancer cell line BxPC3.Methods In p15 transfection group.pCDNA3.1(+)p15 was transfected into BxPC3 cell by the vector of Lipofectamine2000.In empty plasmid transfection group, pCDNA3.1(+)neo was transfected into BxPC3 cell with the sa/ne method as a blank control group.In non-transfection group.the BxPC3 cell was not transfected as a negative control group.The p15 mRNA expressions were assayed by RT-PCR,and p15 protein expressions were assayed by Western blot.The proliferation was determined by MTY assay,ultra-structure changes were measured by transmission electron microscope.Cell cycle and apoptosis were measured by flow cytometry.Results In the pCDNA3.1(+)p15 transfeetion group,the expression of p15 mRNA and protein were resumed.Since the 2nd day of culture,the growth of pCDNA3.1(+)p15 transfeetion group was inhibited,till the 7th day,the inhibitory rate was 47.9%,G_0/G_1 Dhase cell accounted for(61.56±3.96)% of all the cells,which was significantly higher than(47.44±6.35)%ofthe black control groups and(49.22±7.23)%0f tlle negative control group(P<0.05).G_1apoptosis peak occurred and the apoptosis rate was(5.27±1.04)%in pCDNA3.1(+)p15 transfection group,which was significantly higher than(0.11±0.06)% of the black control groups and(0.09±0.07)% of the negative control group(P<0.05).Apoptosis was also observed by transmission electron microscope in the pCDNA3.1(+)-p15 transfection group cells.Conclusions After p15 gene transfection,BLPC3 cell proliferation could be significantly inhibited and apoptosis could be induced.