Expression of p21(WAF1) and p53 and polymorphism of p21(WAF1) gene in gastric carcinoma

AIM: To investigate the relationship between expression of p21(WAF1) and p53 gene, and to evaluate the deletion and polymorphism of p21(WAF1) gene in gastric carcinoma (GC). METHODS: Expression of p21 and p53 proteins, and deletion and polymorphism of p21 gene in GC were examined by streptavidin-peroxidase conjugated method (SP) and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) respectively. RESULTS: The expression of p21 and p53 was found in 100% (20/20) and 0% (0/20) of normal gastric mucosae(NGM), 92.5% (37/40) and 15.0% (6/40) of dysplasia (DP) and 39.8% (43/108) and 56.5% (61/108) of GC, respectively. The positive rate of p21 in GC was lower than that in NGM and DP (P<0.05), while the positive rate of p53 in GC was higher than that in NGM and DP (P<0.05). p21 and p53 were significantly expressed in 63.3% (19/30) and 36.7% (11/30), 35.0% (14/40) and 77.5% (31/40), 26.7% (4/15) and 80.0% (12/15), 30.8% (4/13) and 30.8% (4/13), and 20.0% (2/10) and 30.0% (3/10) of well-differentiated, poorly-differentiated, undifferentiated carcinomas, mucoid carcinomas and signet ring cell carcinomas. The expression of p21 in well-differentiated carcinomas was significantly higher than that in poorly-differentiated, un-differentiated, mucoid carcinomas and signet ring cell carcinomas (P<0.05). Contrarily, The expression of p53 was increased from well-differentiated to poorly-differentiated and un-differentiated carcinomas (P<0.05). The expression of p21 and p53 in paired primary and metastatic GC (35.3% and 70.6%) was different from non-metastatic GC (62.5% and 42.5%) markedly (P<0.05). The expression of p21 in invasive superficial muscle (60.0%) was higher than that in invasive deep muscle or total layer (35.2%) (P<0.05) and was higher in TNM stages I (60.0%) and II (56.2%) than in stages III (27.9%) and IV (22.2%) (P<0.05), whereas the expression of p53 did not correlate to invasion depth or TNM staging (P>0.05). The exoression patterns of p53+/p21-, and of p53-/p21+ were found in 5.0% and 82.5% of DP. There was a significant correlation between expression of p21 and p53 (P<0.05). But there was no significant correlation between expression of both in GC (P>0.05). There was no deletion in exon 2 of p21 gene in 30 cases of GC and 45 cases of non-GC, but polymorphism of p21 gene at exon 2 was found in 26.7% (8/30) of GC and 8.9% (4/45) of non-GC, a significant difference was found between GC and non-GC (P<0.05). There was no significant relation between p21 expression of polymorphism (37.5%, 3/8) and non-polymorphism (45.5%, 10/22) in GC (P>0.05). CONCLUSION: The loss of p21 protein and abnormal expression of p53 are related to carcinogenesis, differentiation and metastasis of GC. The expression of p21 is related to invasion and clinical staging in GC intimately. The expression of p21 protein depends on p53 protein largely in NGM and DP, but not in GC. No deletion of p21 gene in exon 2 can be found in GC. The polymorphism of p21 gene might be involved in gastric carcinogenesis.There is no significant association between polymorphism of p21 gene and expression of p21 protein.     

p73、PTEN 在胃癌中的表达

目的 检测肿瘤相关基因p73、肿瘤抑制基因PTEN（phosphatase and tensin homolog deleted on chromosometen）在胃癌组织中的表达，并研究其临床病理意义。方法 采用逆转录聚合酶链式反应（RT-PCR）法检测p73、PTEN在40例胃癌中的表达。结果 ①PTNM（pathological tumor-node-metastasis）分期Ⅰ、Ⅱ期胃癌与对照组正常胃黏膜组织间p73、PTEN的表达均有非常显著性差异（P〈0．01）；PTNM分期Ⅲ、Ⅳ期和Ⅰ、Ⅱ期胃癌p73、PTEN的表达均有非常显著性差异（P〈0．05）；②p73在高、中分化胃腺癌组与低分化腺癌组阳性率表达无显著性差异（P〉0．05）；而PTEN在高、中分化腺癌和低分化腺癌阳性率表达差异具有显著性（P〈0．05）。③p73、PTEN在有淋巴结转移组和无淋巴结转移组检出阳性率差异具有显著性（P〈0．05）。结论 p73、PTEN的表达与胃癌临床病理特征和生物学行为存在密切关系，p73、PTEN基因是胃癌细胞增生活跃的重要影响因素。     

食管癌P21WAF1表达与P53突变的关系

目的探讨P21WAF1和P53基因蛋白表达在食管癌发生发展的作用机制以及它们与食管癌临床病理等特征的关系.方法应用S-P免疫组化方法对144例食管癌病变组织进行了P21WAF1和P53蛋白的定位观察.结果食管癌P21WAF1基因蛋白阳性率仅为39%,且与肿瘤细胞分化及淋巴转移有关;P53蛋白阳性率为65%,也与肿瘤细胞分化及淋巴节转移相关.另外,P21WAF1和P53蛋白的表达在不典型增生组存在明显的相关性.结论p21WAF1和p53基因在食管磷癌发生发展机制中起着重要作用,并且,在食管癌癌前病变之中,p21WAF1基因依赖与p53基因通路.     

胃腺癌组织P53,P63和P73蛋白表达的意义

目的:探讨P53,P63和P73蛋白表达与胃腺癌临床病理特征之间的关系．方法:用免疫组织化学技术,检测72例胃腺癌及其癌旁正常组织中P53,P63和P73蛋白表达情况．所有研究对象均为湖北地区汉族人．其中,癌肿位于胃远端(胃窦、胃角)51例,胃近端(胃底、胃体)21例;肠型GAC 44例、弥漫型28例;高分化腺癌20例、中分化腺癌29例、低分化和未分化腺癌23例;TNM分期:Ⅰ和Ⅱ期13例,Ⅲ和Ⅳ期59例．结果:胃腺癌组织中P53,P63和P73蛋白阳性表达率均明显高于正常组织(X2=4．72,P<0．05; X2=5．51,P<0．05;X2=9．75,P<0．01);胃窦／胃角腺癌与胃底／胃体腺癌组织P53蛋白表达率无显著差异(P>0．05);在弥漫型胃腺癌中的表达率明显高于肠型胃腺癌(X2=4．68,P<0．05);在低分化腺癌与高中分化腺癌之间以及Ⅲ,Ⅳ期腺癌与Ⅰ,Ⅱ期胃腺癌之间的表达率的差异均有显著性(X2=7．06,P<0．05;X2=3．95, P<0．05)．P63蛋白在低分化腺癌组织中表达率明显高于高中分化腺癌(X2=7．36,P<0．05);在胃窦／胃角腺癌与胃底／胃体腺癌之间、在弥漫型与肠型胃腺癌之间、在Ⅰ,Ⅱ期胃腺癌与Ⅲ,Ⅳ期腺癌之间均无显著差异．P73蛋白在Ⅰ,Ⅱ期胃腺癌组织中的阳性表达率明显低于Ⅲ,Ⅳ期腺癌(X2=4．14,P<0．05),在胃窦／胃角腺癌与胃底／胃体腺癌之间、在弥漫型与肠型胃腺癌之间、在高、中及低分化胃腺癌之间均无显著差异．在P53蛋白阳性与阴性表达的胃腺癌之间,P63和P73蛋白阳性表达率的差异无显著性．结论:P53,P63和P73过度表达与胃腺癌的发生相关联,但并无交互作用．     

Alterations in exon 4 of the p53 gene in gastric carcinoma

BACKGROUND & AIMS: Our long-term goal was to evaluate the role of p53 in the prognosis of gastric cancer. We previously showed a discrepancy between p53 expression and the presence of mutations when only exons 5-9 were examined. We then evaluated exon 4. METHODS: DNA was sequenced from 217 gastric cancers to detect exon 4 alterations. Codon 72 was examined by restriction enzyme digestion. RESULTS: Mutations were present in 3.2% of tumors. In addition, 2 polymorphic sites were found at codons 36 and 72. Polymorphisms at codon 36 were only found in 2 patients. In contrast, the codon 72 polymorphism was very frequent. The genotype frequency was arg/arg (54%), arg/pro (33%), and pro/pro (14%). The genotype of the polymorphic site varied with race (P = 0.001): 64% of whites had the arg/arg genotype, compared with 24% of blacks. The difference in genotype by site, sex, or histological tumor type was not statistically significant (P = 0.067). CONCLUSIONS: There are several exon 4 alterations in gastric cancers. These include the rare mutations and the very rare codon 36 polymorphism. The most common change is the codon 72 polymorphism, the genotype of which differs significantly with race. The more common arg/arg genotype in whites may explain why whites are more prone to develop cardiac cancer, whereas the more common proline allele in blacks may explain why they are more prone to develop antral cancers. Further studies are required to determine whether the codon 72 polymorphism affects patient predisposition to gastric cancer.     

p21 gene polymorphisms in systemic lupus erythematosus

OBJECTIVE: Cyclin-dependent kinase inhibitor 1A (p21) is a negative regulator in the cell cycle. Development of sex-linked lupus-like syndrome in p21-/- mice and reduced p21 gene expression in patients with systemic lupus erythematosus (SLE) compared with those in healthy controls suggested that p21 is a susceptibility gene of SLE. We investigated the same by a case-control association study. METHODS: Six single nucleotide polymorphisms, p21US G/A, p21DS C/A, p21-1022 G/A, p21C31 C/A, p21In2 G/C and p21UTR T/C, were genotyped in 516 SLE patients and 693 healthy controls. Association of genotypes and alleles with disease, disease phenotypes, haplotypes construction, linkage disequilibrium analysis and p21 mRNA expression were performed. RESULTS: We found a significant association of p21US A allele (OR = 0.23, 95% CI: 0.14-0.38, P < 0.001) and p21-1022 A allele (OR = 1.95, 95% CI: 1.37-2.78, P < 0.001) with SLE. We identified significant differences in the frequencies of haplotypes ht1-ACACCC, which contains p21US A allele, and ht2-GCACCC, which contains p21-1022 A allele, between SLE patients and controls (P < 0.0001). Besides, the p21US GA was associated with SLE patients suffering from arthritis (P = 0.003). We also observed differential p21 mRNA expressions among different genotypes of p21US and p21-1022 which were statistically significant. CONCLUSION: Our results suggested that the p21US A allele and p21-1022 A allele were both associated with the development of SLE, and the p21US A allele was associated with arthritis in SLE patients.     

胃癌相关基因表达与其生物学行为关系研究

目的探讨P21、细胞周期素D1(CyclinD1)及P53基因表达与胃癌生物学行为的关系。方法应用原位杂交免疫组化技术检测74例胃癌组织及癌旁正常粘膜P21和CyclinD1mRNA及P53蛋白表达,分析三者与胃癌生物学行为的关系。结果74例胃癌组织和癌旁正常粘膜中,P21、CyclinD1及P53表达阳性率分别为43.2%和55.4%、40.5%和78.4%、25.7%和1.4%,三者比较均有显著性差异(P<0.01)。P21、CyclinD1及P53表达与患者性别、年龄、分期无明显相关性(P>0.05),与淋巴结转移显著相关(P<0.05);胃癌分化程度与P21阳性表达呈正相关,与CyclinD1阳性表达呈负相关。结论胃癌中P21低表达、CyclinD1和P53过表达可能促使胃癌细胞增殖,且具有更强的侵袭力;多基因表达异常可作为评价胃癌预后的重要参考指标。     

p53基因多态性与鼻咽癌遗传易感性的关系

目的研究广西南宁鼻咽癌患者p53基因遗传多态性与鼻咽癌发生的关系。方法采用病例-对照研究方法,以200例鼻咽癌患者、200例对照人群为研究对象。选取p53基因SNP rs117562731位点作为遗传标记,用聚合酶链式反应-限制性片段长度多态性(PCR-RFLP)和测序方法检测rs117562731位点基因型频率和等位基因频率,比较两组不同基因型与鼻咽癌易感性的关系。结果通过对rs117562731位点多态基因型检测分型发现,在鼻咽癌组和对照组CC、CT、TT基因型频率分别为80.0%、17.0%、3.0%和93.0%、5.5%、1.5%。rs117562731位点等位基因及基因型频率在鼻咽癌组与对照组间分布有显著性差异(P0.05)。结论 p53基因SNP rs117562731位点多态性与鼻咽癌之间存在显著的相关性。     

原发性胃癌p53基因突变

目的 p53基因是当前抑癌基因研究中的热点之一。迄今,有关 p53基因异常与胃癌临床病理学参数如大体类型、临床分期、组织分化程度,浸润深度及淋巴结转移之间的关系尚无定论。Tumura 报告p53基因改变主要发生于异倍体瘤,国内尚无报道。本实验目的主要是分析中国人原发性胃癌 p53基因突变与这些病理参数,包括 DNA 倍体之间的关系。方法用聚合酶链式反应—单构象多态分析(PCR—SSCP)技术对20例原发性胃癌 p53基因外显子5—8突变进行检测。结果 8例(40%)发生了突变,其中2例发生在外显子7,4例发生在外显子8。0至Ⅲ期均有突变存在。66.7%(6/9)的异倍体瘤检测到了p53突变,而二倍体瘤中只有18.2%(2/11)发生了 p53突变。结论 p53基因突变与胃癌临床病理参数如大体类型、分期、组织分化程度、浸润深度及淋巴结转移之间无明显关系,而与胃癌 DNA 倍体改变有关。     

p53 gene mutations in gastric and esophageal cancers.

The presence of point mutation of the p53 gene in exons 5, 6, 7, and 8 was examined in 10 cases of gastric adenocarcinoma and 5 cases of esophageal squamous cell carcinoma by polymerase chain reaction and direct nucleotide sequencing. Mutations of the p53 gene were found in 5 cases of gastric cancer and 4 cases of esophageal cancer. The mutations in the stomach cancers consisted of four missence mutations (exons 5 and 8) and one frame shift (exon 7). In the esophageal cancers, three missence mutations (exons 6, 7, and 8) and one point mutation within the splice donor site of intron 5 were found. Of the seven missence mutations in the two cancers, five showed the transition from G to A and two from G to T. All these changes occurred in the highly conserved region of the p53 protein. These results suggest that mutations of the p53 gene are genetic events in the pathogenesis of gastric adenocarcinoma and esophageal squamous cell carcinoma.     

Expression and clinical significance of TAp73α, p53, PCNA and apoptosis in hepatocellular carcinoma

AIM: To study the prognostic role of TAp73α, p53,proliferating cell nuclear antigen (PCNA) and apoptosis in patients with hepatocellular carcinoma (HCC) after surgical tumor ablation.METHODS: Forty-seven human resected HCC tissues and 42 adjacent non-cancerous tissues were studied with 10 normal liver tissues as control group. TAp73α, p53, and PCNA were detected with Elivision immunohistochemistry.Terminal deoxynucleotidyl transferase (TdT)-mediated d-UTP-biotin nick-end labeling (TUNEL) method was used to detect the apoptosis cells. All clinical and pathological materials were analyzed by SPSS10.0statistical package.RESULTS: TAp73α overexpressed in HCC tissues (36.2%)when compared with adjacent non-cancerous tissues(2.38%, P&lt;0.005) and normal liver tissues (0, P&lt;0.01).Mutant type p53 (rot-p53) overexpressed in HCC tissues(38.3%) when contracted with adjacent non-cancerous tissues (16.7%, P&lt;0.05) and normal liver tissues (0,P&lt;0.01). Proliferation index (PI) level in HCC tissues was significantly higher than that in adjacent non-cancerous tissues (30.34%&#177;4.46% vs27.88%&#177;5.89%, t, P= 0.028).Apoptosis index (AI) level in HCC tissues was higher than that in adjacent non-cancerous tissues (8.62%&#177;2.28%vs7.38%&#177;2.61%, t, P = 0.019). Expression of TAp73α was associated with lymph node metastasis and rot-p53,with r = 0.407 and 0.265, respectively. Expression of rot-p53 was associated with Edmondson‘s stage and AFP,with r = 0.295 and -0.357, respectively. In Kaplan-Meier univariant analysis, TAp73α, AFP, TNM stage, portal vein invasion, liver membrane invasion and HBsAg correlated with prognosis (log rank, P= 0.039, 0.012, 0.002, 0.000,0.014, 0.007, respectively). Multivariant Cox regression analysis showed that TAp73α, AFP, TNM stage, portalve in invasion, liver membrane invasion and age were independent factors of prognosis.CONCLUSION: These results suggest that TAp73α can be used as a prognostic indicator of patients with HCC undergoing surgical tumor ablation. AFP, TNM, portal vein invasion, liver membrane invasion and age also have a potency of predicting the prognosis of HCC.     

Expression and clinical significance of TAp73α, p53, PCNA and apoptosis in hepatocellular carcinoma

AIM: To study the prognostic role of TAp73α, p53, proliferating cell nuclear antigen (PCNA) and apoptosis inpatients with hepatocellular carcinoma (HCC) atter surgical tumor ablation.METHODS: Forty-seven human resected HCC tissues and 42 adjacent non-cancerous tissues were studied with 10 normal liver tissues as control group. TAp73α, p53, and PCNA were detected with Elivision immunohistochemistry.Terminal deoxynucleotidyl transferase (TdT)-mediatedd-UTP-biotin nick-end labeling (TUNEL) method wasused to detect the apoptosis cells. All clinical and pathological materials were analyzed by SPSS10.0statistical package.RESULTS: TAp73α overexpressed in HCC tissues (36.2%) when compared with adjacent non-cancerous tissues (2.38%, P＜0.005) and normal liver tissues (0, P＜0.01).Mutant type p53 (mt-p53) overexpressed in HCC tissues (38.3%) when contracted with adjacent non-cancerous tissues (16.7%, P＜0.05) and normal liver tissues (0, P＜0.01). Proliferation index (PI) level in HCC tissues was significantly higher than that in adjacent non-cancerous tissues (30.34%±4.46% vs 27.88%±5.89%, t, P= 0.028). Apoptosis index (AI) level in HCC tissues was higher than that in adjacent non-cancerous tissues (8.62%±2.28% vs 7.38%±2.61%, t, P = 0.019). Expression of TAp73α was associated with lymph node metastasis and mt-p53, with r = 0.407 and 0.265, respectively. Expression of mtp53 was associated with Edmondson's stage and AFP, with r = 0.295 and -0.357, respectively. In Kaplan-Meier univariant analysis, TAp73α, AFP, TNM stage, portal vein invasion, liver membrane invasion and HBsAg correlated with prognosis (log rank, P = 0.039, 0.012, 0.002, 0.000,0.014, 0.007, respectively). Multivariant Cox regression analysis showed that TAp73α, AFP, TNM stage, portal vein invasion, liver membrane invasion and age were independent factors of prognosis. CONCLUSION: These results suggest that TAp73α can be used as a prognostic indicator of patients with HCC undergoing surgical tumor ablation. AFP, TNM, portal vein invasion, liver membrane invasion and age also have a potency of predicting the prognosis of HCC.     

利用组织芯片技术研究P73和mP53基因编码蛋白在胃癌中的表达及意义

目的:构建胃癌及其癌前病变组织芯片,采用免疫组化方法观察研究P73和mP53基因编码蛋白在胃癌中的表达并探讨其临床病理学意义.方法:收集2003-2004年辽宁省肿瘤医院和中国医大附属一院104例胃癌及癌前病变组织标本构建两个组织芯片蜡块,组织样品直径为1 mm.采用SABC免疫组化方法检测胃癌组织中P73和mP53蛋白的表达,观察分析其与胃癌病理生物学行为的关系.结果:P73基因编码蛋白在胃癌、肠上皮化生、不典型增生病变组织中的阳性表达率显著高于远癌正常胃黏膜(90.1%,44.0%,80.0%vs 17.9%,P＜0.01).Borrman Ⅲ/Ⅳ型胃癌P73蛋白阳性表达率(92.9%/100%)显著高于BorrmanⅡ型胃癌(57.1%)(P＜0.05).伴转移胃癌组P73蛋白阳性表达率(淋巴结转移组94.4%,肝转移组100%,卵巢转移100%)显著高于无转移组(76.2%)(P＜0.05).胃癌组织中P73蛋白表达与mP53蛋白表达密切相关(χ2=9.6736,P＜0.01).结论:P73蛋白表达与胃癌恶性病理生物学行为密切相关,其虽与抑癌基因P53同源,但与mP53蛋白表达呈正相关,提示其可能作为P53的一种模拟突变体在胃癌发生、发展中起作用.     

p21和p27基因多态性与妇科肿瘤的相关性研究

目的探讨p21和p27基因多态性与妇科肿瘤遗传易感性的关系。方法采用聚合酶链反应—限制性片段长度多态性方法,分析100例妇科肿瘤患者和95例健康对照者的p21基因3′非翻译区（3′UTR）和p27基因第109密码子多态性位点的基因型。结果妇科肿瘤患者p21基因突变型TT频率为26.00%,对照者为16.84%,两者相比,P〈0.01;年龄〈46岁组肿瘤患者的p21基因突变型（CT＋TT）频率为86.84%,≥46岁组为59.52%,两组相比,P〈0.01;中低分化组妇科肿瘤患者的突变型CT和TT基因型频率为76.47%,高分化组为46.67%,两组相比,P〈0.05;妇科肿瘤患者与对照者的p27基因型总体分布及V和G等位基因频率相比,P均〈0.01。结论p21基因3′UTR多态性和p27基因V109G多态性与妇科肿瘤的遗传易感性有关。     

胃粘膜癌前病变P21和P53蛋白的表达

目的检测胃粘膜肠化生和异型增生病变部位Ｐ２１和Ｐ５３蛋白表达与胃癌发生的关系．方法内窥镜及病理学证实为胃粘膜肠化生者４４例，男２６例，女１８例，平均年龄４７５岁．异型增生者１４例，男９例，女５例，平均年龄６４５岁．粘液组化将肠化生分型，免疫组化测定Ｐ２１及Ｐ５３蛋白表达．结果Ⅱｂ型肠化生Ｐ２１及Ｐ５３蛋白阳性率分别为７００％和３００％，均显著高于Ⅰｂ型肠化生（２５８％和６４％，Ｐ＜００１）．异型增生Ｐ２１及Ｐ５３阳性率为４２８％和２８５％，高于肠化组３４％和１１８％．Ⅱｂ型肠化异型增生Ｐ２１和Ｐ５３阳性率为６２５％和３７５％，也高于Ⅰｂ型肠化异型增生组１６６％和１６６％．结论分泌非中性粘液的Ⅱｂ型肠化异型增生带有更多与胃癌相同的生物学性状，可能与胃癌的发生关系密切．     

p53异构体和MDM2、PTEN在胃癌组织中表达的相关性

目的探讨p53的选择性剪接异构体与双微基因2(MDM2)、同源性磷酸酶张力蛋白(PTEN)在胃癌组织中的表达及其相关性。方法分别应用巢式逆转录多聚酶链反应(NT-PCR)和免疫组织化学(PV-9000两步法)方法检测p53的五种选择性剪接异构体和MDM2、PTEN在胃癌组织和癌旁胃组织中的表达,并进行统计学分析。结果在30例胃癌患者癌组织和癌旁胃组织中均未检测到三种p53异构体p53γ、Δ133p53β、Δ133p53γ的mRNA表达。与癌旁组织比较,胃癌组织中Δ133p53表达阳性率高,p53β表达阳性率低,MDM2蛋白表达阳性率高,PTEN蛋白表达阳性率低(P均<0.01)。Spearman’s相关性分析显示,Δ133p53和MDM2,p53β和PTEN在胃癌中表达均呈正相关关系(r=0.408,P=0.025;r=0.413,P=0.02);Δ133p53和PTEN,p53β和MDM2在胃癌中表达呈负相关关系(r=-0.467,P=0.009;r=-0.480,P=0.007)。结论Δ133p53、p53β通过调节p53活性,并以p53为中介,影响了PTEN-MDM2-p53网络环路中PTEN、MDM2蛋白的表达。