Function of apoptosis and expression of the proteins Bcl-2,p53 and C-myc in the development of gastric cancer

INTRODUCTIONIn China ,the incidence and mortality of gastric cancer rank the second among all cancers. Recent development of cancer [1-20].The aim of this study was investigat the insight of apoptosis and bcl-2, p53 and C-myc protein expression in the development of gastric cancer .

乳癌组织P53蛋白和Ki-67抗原表达及临床意义

目的探讨人乳癌组织P53蛋白和Ki-67抗原的表达及其意义。方法应用免疫组织化学方法,检测100例乳癌组织和50例癌旁正常乳腺组织中P53蛋白和Ki-67抗原的表达。结果乳癌组织P53蛋白和Ki-67抗原的表达阳性率均显著高于正常组织(χ~2=4.854、6.047,P<0.05);P53蛋白和Ki-67抗原在TNMⅢ组的表达明显高于TNMⅠ~Ⅱ组(χ~2=4.679、11.360,P<0.05),腋窝淋巴结阳性组的表达明显高于腋窝淋巴结阴性组(χ~2=11.081、6.109,P<0.05);Ki-67抗原在术后复发组的表达明显高于术后未复发组(χ~2=5.403,P<0.05),P53蛋白的表达在术后复发与未复发组比较差异无显著性(P>0.05);Ki-67抗原在组织学分级3级组的表达阳性率明显高于组织学分级1~2级组,差异有显著性(χ~2=7.760,P<0.05);不同组织学分级乳癌组织中P53蛋白表达阳性率比较差异无显著性(P>0.05)。乳癌组织P53蛋白和Ki-67抗原的表达有显著正相关性(r=0.286,P<0.05)。P53蛋白和Ki-67抗原表达阴性的病人5年生存率优于表达阳性者,差异有显著性(χ~2=6.862、7.963,P<0.05)。结论 P53蛋白和Ki-67抗原在乳癌组织中高表达提示预后不良。

Changes of NF-kB,p53,Bcl-2 and caspase in apoptosis induced by JTE-522 in human gastric adenocarcinoma cell line AGS cells:role of reactive oxygen species

AIM: To identify whether JTE-522 can induce apoptosis in AGS cells and ROS also involved in the process, and to investigate the changes in NF-kB, p53, bcl-2 and caspase in the apoptosis process. METHODS: Cell culture, MTT, Electromicroscopy, agarose gel electrophoresis, lucigenin, Western blot and electrophoretic mobility shift assay (EMSA) analysis were employed to investigate the effect of JTE-522 on cell proliferation and apoptosis in AGS cells and related molecular mechanisms. RESULTS: JTE-522 inhibited the growth of AGS cells and induced the apoptosis. Lucigenin assay showed the generation of ROS in cells under incubation with JTE-522. The increased ROS generation might contribute to the induction of AGS cells to apoptosis. EMSA and Western blot revealed that NF-kB activity was almost completely inhibited by preventing the degradation of IkBalpha. Additionally, by using Western blot we confirmed that the level of bcl-2 was decreased, whereas p53 showed a great increase following JTE-522 treatment. Their changes were in a dose-dependent manner. CONCLUSION: These findings suggest that reactive oxygen species, NF-kB, p53, bcl-2 and caspase-3 may play an important role in the induction of apoptosis in AGS cells after treatment with JTE-522.

P53 immunohistochemical scoring:an independent prognostic marker for patients after hepatocellular carcinoma resection

AIM: To confirm if p53 mutation could be a routine predictive marker for the prognosis of hepatocellular carcinoma (HCC) patients. METHODS: Two hundreds and forty-four formalin-fixed paraffin-embedded tumor samples of the patients with HCC receiving liver resection were detected for nuclear accumulation of p53. The percent of P53 immunoreactive tumor cells was scored as 0 to 3+ in P53 positive region (【10% -, 10-30% +, 31-50% ++, 】50% +++). Proliferating cell nuclear antigen (PCNA) and some clinicopathological characteristics, including patients' sex, preoperative serum AFP level, tumor size, capsule, vascular invasion (both visual and microscopic), and Edmondson grade were also evaluated. RESULTS: In univariate COX harzard regression model analysis, tumor size, capsule status, vascular invasion, and p53 expression were independent factors that were closely related to the overall survival (OS) rates of HCC patients. The survival rates of patients with 3+ for P53 expression were much lower than those with 2+ or + for P53 expression. Only vascular invasion (P【0.05) and capsule (P【0.01) were closely related to the disease-free survival (DFS) of HCC patients. In multivariate analysis, p53 overexpression (RI 0.5456, P【0.01) was the most significant factor associated with the OS rates of patients after HCC resection, while tumor size (RI 0.5209, P【0.01), vascular invasion (RI 0.5271, P【0.01) and capsule (RI-0.8691, P【0.01) were also related to the OS. However, only tumor capsular status was an independent predictive factor (P【0.05) for the DFS. No significant prognostic value was found in PCNA-LI, Edmondson's grade, patients' sex and preoperative serum AFP level. CONCLUSION: Accumulation of p53 expression, as well as tumor size, capsule and vascular invasion, could be valuable markers for predicting the prognosis of HCC patients after resection. The quantitative immunohistochemical scoring for P53 nuclear accumulation might be more valuable for predicting prognosis of patients after HCC resection than the common qualitative analysis.

The effect of adenovirus expressing wild-type p53 on 5-fluorouracil chemosensitivity is related to p53 status in pancreatic cancer cell lines

AIM:There are conflicting data about p53 function on cellular sensitivity to the cytotoxic action of 5-fluorouracil (5-FU). Therefore the objective of this study was to determine the combined effects of adenovirus-mediated wild-type (wt) p53 gene transfer and 5-FU chemotherapy on pancreatic cancer cells with different p53 gene status. METHODS:Human pancreatic cancer cell lines Capan-1^(p53mut), Capan-2^(p53wt),FAMPAC^(p53mut),PANC1^(p53mut),and rat pancreatic cancer cell lines AS^(p53wt) and DSL6A^(p53null) were used for in vitro studies.Following infection with different ratios of Ad- p53-particles (MOI) in combination with 5-FU,proliferation of tumor cells and apoptosis were quantified by cell proliferation assay (WST-1) and FACS (PI-staining).In addition,DSL6A syngeneic pancreatic tumor cells were inoculated subcutaneously in to Lewis rats for in vivo studies. Tumor size,apoptosis (TUNEL) and survival were determined. RESULTS:Ad-p53 gene transfer combined with 5-FU significantly inhibited tumor cell proliferation and substantially enhanced apoptosis in all four cell lines with an alteration in the p53 gene compared to those two cell lines containing wt-p53.In vivo experiments showed the most effective tumor regression in animals treated with Ad-p53 plus 5-FU.Both in vitro and in vivo analyses revealed that a sublethal dose of Ad-p53 augmented the apoptotic response induced by 5-FU. CONCLUSION:Our results suggest that Ad-p53 may synergistically enhance 5-FU-chemosensitivity most strikingly in pancreatic cancer cells lacking p53 function.These findings illustrate that the anticancer efficacy of this combination treatment is dependent on the p53 gene status of the target tumor cells.

消肿生肌汤对肛瘘术后患者肉芽组织Bax、P53、Caspase-3水平的影响

目的分析消肿生肌汤对肛瘘术后患者Bcl-2相关X蛋白(Bax)、P53、半胱氨酸蛋白酶-3(Caspase-3)水平的影响。方法选择行肛瘘术后患者80例,随机为对照组与观察组,各40例。观察组采用消肿生肌汤熏洗治疗,对照组采用常规治疗,2组均连续治疗7 d。比较2组治疗效果,治疗7 d后创面愈合情况,治疗前和治疗7 d后肉芽组织凋亡相关因子Bax、P53、Caspase-3水平和患者肛门功能。结果治疗7 d后,观察组临床有效率(95.00%,38/40)显著高于对照组(77.50%,31/40)(P<0.05);观察组创面愈合情况优于对照组(P<0.05);2组肉芽组织Bax、P53、Caspase-3水平均低于治疗前,且观察组低于对照组(P<0.05);2组肛管最长收缩时间长于治疗前,观察组长于对照组(P<0.05);肛管收缩压大于治疗前,观察组大于对照组(P<0.05);肛管静息压小于治疗前,观察组小于对照组(P<0.05)。结论消肿生肌汤熏洗能显著促进肛瘘术后患者创面愈合,降低肉芽组织凋亡相关因子Bax、P53、Caspase-3水平,改善患者肛门功能,疗效较好。

Lack of correlation between p53 codon 72 polymorphism and anal cancer risk

AIM:To investigate the potential role of p53 codon 72 polymorphism as a risk factor for development of anal cancer. METHODS:Thirty-two patients with invasive anal carcinoma and 103 healthy blood donors were included in the study.p53 codon 72 polymorphism was analyzed in blood samples through polymerase chain reaction-restriction fragment length polymorphism and DNA sequencing. RESULTS:The relative frequency of each allele was 0.60 for Arg and 0.40 for Pro in patients with anal cancer, and 0.61 for Arg and 0.39 for Pro in normal controls. No significant differences in distribution of the codon 72 genotypes between patients and controls were found. CONCLUSION:These results do not support a role for the p53 codon 72 polymorphism in anal carcinogenesis.

Relationship between tumor suppressor gene p53 and tumors of adipose tissue

OBJECTIVE: To investigate the relationship between p53 gene and tumors of adipose tissue at the level of protein and gene. METHODS: Immunohistochemical LSAB, PCR-SSCP and DNA sequencing were used in 82 cases. RESULTS: p53 protein is expressed only in liposarcomas, in which the positive staining rate was 48.08% (25/52). In different subtypes of liposarcomas, the positive staining rate in well differentiated liposarcomas was 30.00% (9/30), which is much lower than that of the poorly differentiated liposarcomas (P ATC) were detected by DNA sequencing. Another heterozygotic cosense mutation may exist at exon 6 codon 221 of p53 gene (GAG-->GAA). CONCLUSIONS: The data suggest that the p53 protein has a relationship with development, differentiation and malignancy of liposarcoma. Detecting the level of p53 protein expression may be valuable in evaluating the level of differentiation and malignancy of liposarcoma. There appear point mutation on exon 8, 6 of p53 gene.

几种多药耐药相关因子在肺癌中的表达及临床病理意义

目的:探讨原发性肺癌中几种与多药耐药相关因子的表达及与临床病理的相关性。方法:采用免疫组化方法对术前未经化疗、术后病理诊断明确的133例肺癌组织标本和15例作为对照的癌旁肺组织(距肿瘤边缘5cm),进行了P-gp、MRP、LRP、p53及c-erbB-2蛋白表达的检测。结果:(1)133例肺癌组织中,P-gp、MRP、LRP、p53及c-erbB-2的阳性率分别为72.2%(96/133)、40.5%(51/126)、54.1%(72/126)、59.4%(79/126)和45.9%(61/133),除P-gp外均显著高于正常肺组织中的表达水平(P<0.05);且p53表达与P-gp及MRP表达之间(r=0.179及0.185,P=0.039及0.041),P-gp与LRP之间(r=0.264,P=0.002),LRP与MRP之间(r=0.309,P<0.001),以及c-erbB-2表达分别与MRP、LRP及p53表达之间(r分别为:0.350、0.421、0.541和0.354,P值均<0.001)均有相关性。(2)P-gp、MRP、LRP和c-erbB-2蛋白表达在不同病理类型之间具有统计学差异,而LRP蛋白表达在不同病理分化程度之间具有统计学差异(P<0.001),P-gp在鳞癌不同分化程度间表达有统计学差异(P=0.049)。(3)针对病理类型及亚型:①神经内分泌癌与非神经内分泌癌相比,后者的LRP和c-erbB-2蛋白表达水平较前者高(P=0.005和0.041);②未发现细支气管肺泡癌与其他类型腺癌间在MDR相关因子的蛋白表达水平上有统计学差异。结论:这些多药耐药相关因子可能均在肺癌的原发性多药耐药中起不同程度的作用,且在多药耐药形成以及肿瘤进展的过程中它们之间有某种程度的关联。

Association between MDM2-SNP309 and hepatocellular carcinoma in Taiwan Residents population

AIM:To investigate the risk association and compare the onset age of hepatocellular carcinoma(HCC) patients in Taiwan with different genotypes of MDM2- SNP309. METHODS:We analyzed MDM2-SNP309 genotypes from 58 patients with HCC and 138 cancer-free healthy controls consecutively.Genotyping of MDM2-SNP309 was conducted by restriction fragment length polymor- phism assay. RESULTS:The proportion of homozygous MDM2- SNP309 genotype(G/G)in cases and cancer-free healthy controls was similar(17.2%vs 16.7%).Multi-variate analysis showed that the risk of G/G genotypeof MDM2-SNP309 vs wild-type T/T genotype in patients with HCC was not significant(OR=1.265,95% CI=0.074-21.77)after adjustment for sex,hepatitis B or C virus infection,age,and cardiovascular disease/ diabetes.Nevertheless,there was a trend that GG genotype of MDM2-SNP309 might increase the risk in HCC patients infected with hepatitis virus(OR=2.568, 95%CI=0.054-121.69).Besides,the homozygous MDM2-SNP309 genotype did not exhibit a significantly earlier age of onset for HCC. CONCLUSION:Current data suggest that the asso- ciation between MDM2-SNP309 GG genotype and HCC is not significant,while the risk may be enhanced in patients infected by hepatitis virus in Taiwan.

Neutron-induced apoptosis of HR8348 cells in vitro

INTRODUCTIONTo date ,the major therapy for rectal carcinoma is extensive abdomino-perineal resection[1]. Unfortunately ,after resection of rectal carcinoma ,many patients still die of blood-borne metastases ,usually in the liver or lungs ,or local prlvic recurrence[2,3],which is the major cause of morbidity and mortality in patients with rectal carcinoma .Pre-or postoperative radiotherapy can reduce the incidence of local rdcurrence[4-7].

中西医结合治疗对神经胶质瘤患者血清p53、VGEF表达的影响

目的观察姜黄消瘤汤联合化疗对神经胶质瘤患者术后的临床疗效。方法 60例神经胶质瘤患者随机分为治疗组和对照组各30例。对照组术后给予化疗干预,治疗组在对照组的基础上给予姜黄消瘤汤联合治疗,均以28d为1个疗程,连续治疗4个疗程。观察两组治疗前后近期临床疗效、血清肿瘤抑制蛋白 53(p53)、血管内皮生长因子(VGEF)水平、中医证候积分、毒副反应情况。结果治疗组近期临床疗效和疾病控制方面优于对照组(P<0.05);治疗后两组中医证候积分、血清 p53、VGEF 水平较治疗前下降(P<0.05),治疗组降低程度高于对照组(P<0.05);治疗组发生胃肠道反应、骨髓抑制、深静脉血栓形成的病例均少于对照组(P<0.05)。结论姜黄消瘤汤联合化疗对神经胶质瘤患者术后疗效明确,改善中医症状,下调血清p53、VGEF水平,并具有增效减毒作用。

Transcriptomic Landscape Analysis Reveals a Persistent DNA Damage Response in Metabolic Dysfunction-associated Steatohepatitis Post-dietary Intervention

Background and Aims:Metabolic dysfunction-associated steatotic liver disease(MASLD)and its more advanced form,metabolic dysfunction-associated steatohepatitis,have emerged as the most prevalent liver diseases worldwide.Currently,lifestyle modification is the foremost guidelinerecommended management strategy for MASLD.However,it remains unclear which detrimental signals persist in MASLD even after disease remission.Thus,we aimed to examine the persistent changes in liver transcriptomic profiles following this reversal.Methods:Male C57BL/6J mice were divided into three groups:Western diet(WD)feeding,chow diet(CD)feeding,or diet reversal from WD to CD.After 16 weeks of feeding,RNA sequencing was performed on the mice’s livers to identify persistent alterations characteristic of MASLD.Additionally,RNA sequencing databases containing high-fat diet-fed P53-knockout mice and human MASLD samples were utilized.Results:WD-induced MASLD triggered persistent activation of the DNA damage response(DDR)and its primary transcription factor,P53,long after the resolution of the hepatic phenotype through dietary reversal.Elevated levels of P53 might promote apoptosis,thereby exacerbating metabolic dysfunction-associated steatohepatitis,as they strongly correlated with hepatocyte ballooning,an indicator of apoptosis activation.Moreover,P53 knockout in mice led to downregulated expression of apoptosis signaling in the liver.Mechanistically,P53 may regulate apoptosis by transcriptionally activating the expression of apoptosis-enhancing nuclease(AEN).Consistently,P53,AEN,and the apoptosis process all exhibited persistently elevated expression and showed a strong inter-correlation in the liver following dietary reversal.Conclusions:The liver demonstrated upregulation of DDR signaling and the P53-AEN-apoptosis axis both during and after exposure to WD.Our findings provide new insights into the mechanisms of MASLD relapse,highlighting DDR signaling as a promising target to prevent MASLD recurrence.

垂体瘤转化基因、p53蛋白在大肠腺瘤与大肠癌组织中的表达

目的探讨垂体瘤转化基因（PTTG）和p53蛋白在大肠腺瘤、大肠癌及癌旁正常黏膜组织中的表达及其相关性。方法采用免疫组化方法检测50例大肠腺瘤和42例大肠癌及癌旁正常黏膜组织中的PTTG、p53蛋白表达水平，并分析两者的相关性以及其与临床病理特征的关系。结果PTTG在癌旁正常黏膜组织中的阳性表达率为7．14％（3／42），p53蛋白未见阳性表达；PTTG、p53蛋白在大肠腺瘤组织中的阳性表达率分别为82．00％（41／50）和90．00％（45／50），表达强度均未达到过度表达标准；PTTG、p53蛋白在大肠癌组织中的阳性表达率分别为88．10％（37／42）和95．24％（40／42），其中部分呈过度表达，过度表达率分别为45．24％（19／42）和69．05％（29／42）。PTTG和p53蛋白在大肠癌组织中的阳性表达率显著高于癌旁正常黏膜组织及大肠腺瘤组织，且癌旁正常黏膜组织低于大肠腺瘤组织，差异有统计学意义（P〈0．05）。在大肠腺瘤组织中，兀TG与p53蛋白的阳性表达密切相关（P〈0．05），但在大肠癌组织中，两者之间的阳性表达无明显相关性（P〉0．05o此外，PTTG的过度表达与大肠癌淋巴结转移明显相关（P〈0．01），p53蛋白的过度表达则与大肠癌淋巴结转移无明显相关性（P〉0．05）。结论PTTG、p53蛋白的阳性表达在大肠腺瘤组织中密切相关，两者联合观察可以作为大肠腺瘤癌变的分子指标；PTTG、p53蛋白在大肠癌组织中呈过度表达，PTTG与淋巴结转移有关，PTTG的过度表达可以作为判断大肠癌是否有淋巴结转移的分子指标。

Effects of HBV X gene and arsenic trioxide on the expression of p53 in cultured HepG2 cells

Background Hepatitis B virus （HBV） X protein （HBx） and p53 could mutually down-regulate at transcriptional level and HBx could bind with p53 protein within its transactivation domain and inhibit the function of p53 protein. In recent years, effects of arsenic trioxide （As2O3） on the expression of p53 protein have been widely studied, while little is known about the activity of p53 protein. This study was undertaken to delineate the effect of HBV X gene and AS203 on p53 protein expression （level and activity） in HepG2 cells by small hairpin RNA （shRNA）-mediated RNA interference （RNAi） technique. Methods Cell line HepG2 and cells with stable expression of HBV X gene （HepG2-X） were treated with 2 pmol/L AS203, with corresponding untreated cells serving as controls. Cell lysates and nuclear extracts were extracted. Total level and the relative activity of p53 protein were detected by modified enzyme-linked immunosorbent assay （ELISA）. HBV X gene sequence-specific shRNA expression vector （pXi-1 and pXi-2） and sequence-unrelated control （pXi-3） were transfected into HepG2-X. Single cell clone with stable expression of shRNA was selected and exposed to propagating culture. The effect of As2O3 on p53 protein expression and activity was re-observed. Results Total p53 protein level was up-regulated and its relative activity ratio was enhanced by As2O3 in HepG2 and HepG2-X cells. The total p53 protein level induced by As2O3 was up-regulated by HBV X gene expression, while its relative activity was significantly suppressed. The suppression was removed after HBV X gene expression was repressed by shRNA. Conclusions As2O3 up-regulates p53 protein expression and enhance its activity. HBV X up-regulates As2O3 induced-p53 protein expression while suppresses its activity.

内皮素受体B基因过表达对乳腺癌ZR-75-1细胞活力和周期的影响

目的探讨过表达内皮素受体B(EDNRB)基因对人乳腺癌ZR-75-1细胞活力和细胞周期的影响。方法设计EDNRB基因特异性引物,与GV492载体连接构建含EDNRB基因全长序列的过表达载体,慢病毒包装后转染ZR-75-1细胞,构建稳定过表达EDNRB的乳腺癌细胞系。用半定量逆转录聚合酶链反应和蛋白质印迹法检测EDNRB mRNA和蛋白的表达水平,用噻唑蓝法检测EDNRB过表达对细胞生长的影响,用流式细胞术检测EDNRB过表达对细胞周期的影响,用蛋白质印迹法检测EDNRB过表达对细胞周期相关蛋白表达的影响。结果未处理组、GV492转染组和GV492-EDNRB转染组的EDNRB mRNA表达水平分别为0.22±0.13、0.13±0.10和1.79±0.12,EDNRB蛋白相对表达水平分别为0.75±0.04、0.80±0.21和1.43±0.10,GV492-EDNRB转染组的上述指标与未处理组和GV492转染组比较,差异均有统计学意义(均P<0.01)。未处理组和GV492-EDNRB转染组的细胞存活率分别为0.98±0.58和0.62±0.15,G1期细胞百分比分别为(52.10±1.25)%和(63.35±1.06)%,抑癌蛋白53(p53)蛋白相对表达水平分为0.19±0.03和0.36±0.05,p21蛋白相对表达水平分为0.42±0.04和0.78±0.17,细胞周期蛋白1(CCND1)蛋白相对表达水平分为0.34±0.11和0.79±0.27,周期蛋白依赖性激酶4(CDK4)蛋白相对表达水平分为0.83±0.14和0.36±0.01,差异均有统计学意义(均P<0.05)。结论本实验成功构建了EDNRB基因过表达的乳腺癌ZR-75-1细胞系;EDNRB过表达抑制了ZR-75-1细胞生长,并将细胞周期阻滞在G1期,其机制可能与p53-p21-CCND1/CDK4通路有关。

The Effect of calmodulin antagonist berbaminederivative-EBB on hepatoma in vitro and in vivo

OBJECTIVE: To evaluate the anti-hepatoma effect of Calmodulin antagonist 0 - 4-ethoxyl-butyl-Berbamine (EBB), one of the berbamine derivatives. METHODS: Monotetrazolium (MTT) method was used to analyze the effect of EBB on the proliferation and growth inhibition effect. Of a hepatoma cell line in vitro. A mouse hepatoma model was induced by injection of hepatoma cells (H22) in the abdominal cavity. The effect of EBB on survival at different concentrations as well as in combination with 5-FU were investigated in vivo. Flow cytometry analysis, dot blot hybridization, western blot, immunochemistry, enzyme-linked lectin assay (ELISA), trifluoperazine (TFP) and electron microscopic observation were used to study the effect of EBB on cell cycle process, P53 mRNA and protein levels, calmodulin content and ultrastractural changes of hepatoma cells. RESULTS: EBB exerts a very strong inhibitory effect on human hepatoma cell line 7402 and mouse hepatoma cell line H22 in vitro. The IC(50) value of EBB for the two cell lines are 3.312 microg/ml and 1.167 microg/ml, respectively. The sensitivity of H22 cells to 5-FU can be markedly enhanced: The IC(50) dosage of 5-Fu can be decreased from 0.75 microg/ml down to 0.15 microg/ml, when jointly administered with nontoxic dosages of EBB (IC(10)). In vivo, EBB can prolong the lifespan of mice with ascites H22 to more than three months. 64% of mice survived, while all animals in the control group died by the 18th day. When EBB (5 mg x kg(-1) x d(-1)) is jointly used with 5-FU (25 mg x ml(-1) x d(-1)), 73% of mice with ascites H22 survived, much higher than 27% in the 5-FU treated group. EBB can enhance the anti-hepatoma ability of 5-Fu treatment. EBB mechanism against hepatoma: P53 expression in the EBB treated group is substantially higher than that in the control group. EBB increased the translation of P53. As a calmodulin antagonist, EBB decreases amount of the CaM in hepatoma cells and blocked the hepatoma cell proliferation cycle at the G(2)M phase. Before the G(0)/G(1) phase, a diploid peak and apoptic cells in the treated groups were observed. CONCLUSIONS: The CaM antagonist, EBB, has a strong anti-hepatoma effect and enhances the effect of 5-FU, induces hepatoma cell to apoptosis, promotes the P53 protein expression and decreases the amount of CaM in the cytoplasm. All these results demonstrate that EBB is a new and potentially useful drug against hepatoma and should be researched further.

Overexpression of Bcl-2 partly inhibits apoptosis of human cervical cancer SiHa cells induced by arsenic trioxide

OBJECTIVE: To study the biological effect of arsenic trioxide (As2O3) on human cervical cancer SiHa cells and SiHa cells overexpressing bcl-2 gene. METHODS: SiHa cells with overexpression of Bcl-2 (SiHa-Bcl2 cells) were established by transfecting SiHa cells with Bcl-2 expression vector. The sensitivities of SiHa and SiHa-Bcl2 cells to As2O3 were determined using MTT (Thiazolyl blue) reduction and colony forming ability assay, morphological analysis, flow cytometric analysis, DNA agarose gel electrophoresis, in situ cell death detection (TUNEL), Northern blot, RT-PCR and Western blot. RESULTS: As2O3 inhibited the growth of SiHa cells and induced G2/M arrest and apoptosis of the cells. RT-PCR and Western blot analysis revealed that As2O3 induced SiHa cell apoptosis possibly via inhibiting the expression of HPV16 E7 and decreasing the expression of c-myc. However, we found that SiHa-Bcl2 cells partly resisted As2O3 induced apoptosis, which might be related to the prevention of the down-regulation of HPV16 E7 and c-myc gene expression. Nevertheless, As2O3 at a high concentration could still induce apoptosis of SiHa-Bcl2 cells mainly via decreasing Bcl-2 expression and slightly inhibiting viral gene expression. CONCLUSION: As2O3 is an inducer of the apoptosis of human cervical carcinoma cells and the cells overexpressing Bcl-2 can partly resist As2O3 induced apoptosis, but the exact mechanism is unclear.

Expression of Syk in non-small cell lung cancer and its relationship with clinicopathological parameters

This study aims to research the expression of spleen tyrosine kinase(Syk)in non-small cell lung cancer(NSCLC)and the relationship between Syk and clinico-pathologic factors and p53.Immunohistochemistry was applied to detect the expression of Syk and p53 protein in 39 cases of NSCLC(23 cases of lung squamous cell can-cer,16 cases of lung adenocarcinoma)and tumor-sur-rounding normal lung tissues.The positive rate of Syk was 46.15%(18/39)and 100%(39/39)in NSCLC and tumor-surrounding normal lung tissues,respectively.The expres-sion level of Syk in NSCLC was significantly lower than that in tumor-surrounding normal lung tissues(P=0.000).The Syk expression was positively correlated with the p53 expression in NSCLC specimens(P=0.025).There was no significant association between Syk expression and lymph node metastasis,differentiation degree,tumor size and tumor node metastasis(TNM).The present study demonstrated that Syk was aberrantly expressed in the NSCLC and might have a significant impact on tumor growth and progression.