p53基因在亚砷酸钠致人胚胎肺成纤维细胞凋亡中的作用

Objective To investigate the p53,Bax,bcl-2 gene in NaAsO2-induced human embryonic lung fibroblasts(HELF)apoptosis.Methods HELF was divided into HELF cells transfected with p53 plasmid(p53 group),HELF cells transfected with PC plasmid(PC group)and normal cultured HELF cells(normal group).The mRNA expression of p53,Bax and bcl-2 gene was detected by real-time PCR,the protein expression of p53,Bax and bcl-2 was assessed by immunohistochemical SABC and the cell apoptosis of HELF was detected by flow cytometry(FCM),in a 6-well plate and cultured for 48 hours,which was exposed to different doses(0,3,9,15mmol/L)NaAsO2 for 24 hours.Results The p53 gene mRNA expression level of p53 group(0.51±0.29)was lower than that of the normal group and PC group [ (1.00 ± 0.20), (1.32 ± 0.26), all P < 0.05 ]. The p53 protein expression level of p53 group(4.10 ± 1.20) was lower than the PC group and normal group[ (8.00 ± 1.63), (7.90 ± 1.79), allP < 0.05]. In p53 group, PC group, normal group exposed to 0,3,9,15 mmol/L NaAsO2 doses, the apoptotic rate [(0.57 ± 0.28)%, (22.91 ± 4.86)%, (40.05 ± 3.93)%, (44.87 ± 3.58)%; (0.65 ± 0.24)%, (14.09 ± 3.49)%,(20.31 ± 3.66)%, (32.42 ± 3.63)%; (0.56 ± 0.25)%, (12.14 ± 3.70)%, (19.61 ± 3.63)%, (30.43 ± 2.83)%], Bax mRNA expression level[(12.73 ± 3.96), (25.12 ± 6.42), (104.96 ± 26.77), (154.04 ± 30.52); (14.63 ± 3.57),(36.75 ± 3.67), (272.26 ± 66.11), (846.12 ± 243.36); (14.75 ± 5.65), (37.22 ± 11.27), (278.51 ± 37.42),(861.67 ± 369.29) ], Bax protein expression level [ ( 15.07 ± 0.83 ) %, ( 23.79 ± 3.99 ) %, (38.51 ± 1.58 ) %, (53.86 ±1.74)%;(15.43 ± 1.45)%,(36.11 ± 1.37)%, (56.86 ± 1.97)%, (76.09 ± 2.01)%; (15.20 ± 1.03)%,(35.25 ±1.09)%, (55.56 ± 2.17)%, (74.48 ± 2.85)% ] was respectively increased in a dose-dependent manner with the increased concentration of NaAsO2(all P < 0.05). The bel-2 mRNA expression level [ (443.00 ± 244.47), (156.79 ±53.18), (62.13 ± 13.66), (23.10 ± 6.44); (420.55 ± 110.77), (48.15 ± 10.02), (14.91 ± 6.53), (7.54 ± 2.62);(577.75 ± 123.22), (49.68 ± 10.11), (12.41 ± 1.28), (7.22 ± 1.89)], bcl-2 protein expression level[(47.20 ±3.77)%, (41.80 ± 2.94)%, (36.00 ± 2.36)%, (29.00 ± 2.91)%; (45.90 ± 4.15)%, (35.70 ± 2.77)%, (29.80 ±2.78)%, (24.80 ± 2.66)% ; (46.70 ± 3.47)%, (36.20 ± 2.90)%, (30.10 ± 3.21)%, (25.10 ± 2.28)% ] wasdecreased in a dose-dependent manner with the increased concentration of NaAsO2(all P < 0.05 ). In 3,9,15 mmol/L NaAsO2, apoptotic rate of p53 group, mRNA expression of bcl-2, protein expression of bcl-2 was higher than that ofnormal group and PC group, respectively (all P < 0.05), but mRNA expression of Bax, protein expression of Bax was respeetivelylower than that normal group and the PC group(P < 0.05 ). Conclusion p53 gene reduced the apoptosis induced by NaAsO2 in HELF, possibly by changing the apoptosis pathway.     

非小细胞肺癌患者呼出气冷凝液中p53蛋白检测的临床意义

Objective To study the clinical significance of the detection of p53 protein in exhaled breath condensate (EBC) of patients with non-small cell lung cancer (NSCLC). Methods EBC and plasma of 98 patients with NSCLC were collected,p53 protein expression in EBC and plasma was detected by enzyme-linked immunosorbent assay,and the data were compared with those of 98 healthy controls. p53 protein expression in cancer tissue of 98 patients with NSCLC was detected by immunohistochemistry. p53 protein expression in EBC and plasma and positive expression rate of p53 protein in cancer tissue were compared among patients with different lung cancer type,stage,histologic type,tumor size,and lymph node metastasis,smoking history. The specificity and sensitivity of diagnosis of p53 protein in patients with NSCLC were analyzed by ROC curve. Results ① The level of p53 protein in EBC of patients with NSCLC was significantly higher than that in healthy control group [(233.99±7.91) ng/L vs ( 130. 26 ± 4. 73) ng/L,P ＜0. 01]. The level of p53 protein in serum of patients with NSCI.C was significantly higher than that in healthy control group [(292. 58 ± 8. 79) ng/L vs (141. 66±3. 33) ng/L,P ＜0. 01]. ② The level of p53 protein in EBC of patients with central lung cancer was higher than that in patients with peripheral lung cancer [(248. 22 ± 8. 58) ng/L vs (215. 78 ± 6.61) ng/L,P＜0. 01]. ③The level of p53 protein in EBC of patients with positive immunostaining group was higher than that in negative group [(249.77 ± 8.07) ng/L vs (216.86 ± 7.44) ng/L,P ＜ 0. 05]. ④The level of p53 protein in serum of smokers was significantly higher than that in non-smokers [(310.18 ± 9.04) ng/L vs (254. 55 ± 6. 91) ng/L,P ＜0. 01]. ⑤The positive expression rate of p53 protein in cancer tissue was 47. 96% (47/98). ⑥The sensitivity and specificity of diagnosis of p53 protein were 95. 90% and 90. 04% in plasma,and those were 92. 90% and 79. 59% in EBC. The cut off values of p53 protein were respectively 175. 68 ng/L and 166. 26 ng/L in EBC and serum. Conclusions The detection of p53 protein in EBC of patients with NSCLC is helpful for the diagnosis of lung cancer.     

Apoptosis, proliferation and p53 gene expression of H. pylori associated gastric epithelial lesions

AIM:To study the relationship between Helicobacter pylori(H.pylori)and gaatric carcinoma and its possiblepathogenesis by H.pylori.METHODS:DNEL technique and immunohistochemicaltechnique were used to study the state of apoptosis,proliferation and p53 gone expression.A total of 100 gastricmucosal biopsy specimens,including 20 normal mucosa,30H.pylori-negative and 30 H.pylori-positive gastricprecancerous lesions along with 20 gastric carcinomas werestudied.RESULTS:There were several apoptotic cells in thesuperficial epithelium and a few proliferative cells within theneck of gestric glands,and no p53 protein expression innormal mucosa.In gestric carcinoma,there ware fewapoptotic cells,while there were a large number ofproliferative cells,and expression of p53 proteinsignificantly was increased.In the phase of metaplasia,theapoptotic index(Al,4.36%±1.95%),proliferative index(Pl,19.11%±6.79%)and positivity of p53 expression(46.7%)in H.pylori-positive group ware higher than thosein normal mucosa(P<0.01).Al in H.pylori-positive groupwas higher than that in H.pylori-negative group(3.81%±1.76%),Pl in H.pylori-positive group was higher than thatin H.pylori-negative group(12.23%±5.63%,P<0.01).Inthe phase of dysplasia,Al(2.31%±1.10%) in H.pylori-positive group was lower(3.05%±1.29%)than that in H.pylori-negative group,but Pl(33.89%±11.65%)wassignificantly higher(22.09±8018%,P<0.01).In phases ofmetaplasia,dysplasia and gastric cancer in the H.pylori-positive group,Als had an evidently greduall decreasingtrend(P<0.01),while Pls had an evidently gradualincreasing trend(P<0.05 or P<0.01),and there was alsoa trend of gradual increase in the expression of p53 gone.CONCLUSION:In the course of the formation of gastriccarcinoma,proliferation of gastric mucosa can be greatlyIncreased by H.pylori,and H.pylori can induce apoptosisin the phase of metaplasia,but in the phase of dysplesia H.pylorl can inhibit cellular apptosis.And H.pylori infectioncan strengthen the expression of mutated p53 gene.     

Differences in platelet endothelial cell adhesion molecule-1 expression between peripheral circulation and pancreatic microcirculation in cerulein-induced acute edematous pancreatitis

AIM: To investigate the changes of platelet endothelial cell adhesion molecule-1 (PECAM-1) expression on polymorphonuclear leukocytes (PMNs) in peripheral circulation and pancreatic microcirculation in cerulein-induced acute edematous pancreatitis (AEP). METHODS: Fifty Wistar rats were randomly divided into control group (n = 10) and AEP group (n = 40). A model of AEP was established by subcutaneous injection of cerulein 5.5 and 7.5 μg/kg at 0 and 1 h after the beginning of experiment respectively. PECAM-1 expression on PMNs from splenic vein and inferior vena cava was determined by RT-PCR at mRNA level and determined by flow cytometry at protein level. RESULTS: In experimental rats, an increased PECAM-1 mRNA expression was seen from 4 to 8 h of AEP in peripheral circulation (0.77±0.25%, 0.76±0.28%, 0.89±0.30%, 1.00±0.21%), while in pancreatic microcirculation, expression decreased from 2 h and reached the lowest level at 6 h of AEP (0.78±0.29%, 0.75±0.26%, 0.62±0.28%, 0.66±0.20%). There were significant differences at 8-h time point of AEP between peripheral circulation and pancreatic microcirculation (1.00±0.21% vs0.66±0.20%, P<0.05). Meanwhile, the difference at protein level was also found. CONCLUSION: A reverse expression of PECAM-1 on PMNs was found between peripheral circulation and pancreatic microcirculation, suggesting that inhibition of PECAM-1 expression may improve the pathological change of AEP.