HPV16 E6/E7基因及蛋白表达与宫颈癌的相关性研究

目的研究人乳头状瘤病毒16型（HPV16）E6／E7基因及其蛋白表达在宫颈疾病及其癌变中的作用。方法运用PCR技术检测51例宫颈癌（癌症组）、20例富颈上皮瘤变（CIN）Ⅱ～Ⅲ级（CIN组）、20例宫颈炎（炎症组）患者病变组织中HPV16 E6／E7基因，并运用免疫组化SP法检测癌症组癌组织中HPV16E6、E7的表达情况。结果癌症组、CIN组、炎症组HPV16 E6检出率分别为5％、35％、45％．后两者明显高于前者（P〈0．05），HPV16 E7检出率分别为65％、75％、68．6％，P均〉0．05；癌症组45例HPV16 E6和42例E7蛋白阳性表达（88．2％、82．3％）。HPV16 E6蛋白表达与临床分期、肿瘤分化程度和淋巴结有无转移均无相关性（P〉0．05），HPV16 E7蛋白表达与临床分期和淋巴结有无转移相关（P〈0．05），与肿瘤分化程度无相关性（P〉0．05）。结论HPV16 E6／E7基因与宫颈疾病及其癌变的关系密切。     

甲状腺乳头状癌组织中p14~（ARF）、p16~（INK4a）、MDM2的表达变化及意义

目的观察甲状腺乳头状癌（PTC）组织中p14ARF、p16INK4a、MDM2的表达变化,并探讨其临床意义。方法采用免疫组化SP法检测83例PTC、31例甲状腺乳头状微小癌（PTMC）、50例甲状腺腺瘤组织中的p14ARF、p16INK4a、MDM2。结果 PTC组织中p14ARF、p16INK4a、MDM2蛋白阳性率分别为22.9%、26.5%、74.7%,PTMC组织中分别为45.2%、48.4%、54.8%,甲状腺瘤组织中分别为52.0%、72.0%、52.0%。PTC组织中p14ARF、p16INK4a蛋白阳性率明显低于甲状腺腺瘤（P〈0.01）及PTMC（P〈0.05）,MDM2蛋白阳性率明显高于甲状腺腺瘤（P〈0.05）及PTMC（P〈0.01）。p14ARF蛋白表达与PTC淋巴结转移有关（P〈0.05）,p16INK4a蛋白表达与PTC复发有关（P〈0.05）。p14ARF、MDM2蛋白表达呈负相关（r=-0.343,P〈0.05）。结论 PTC组织中p14ARF、p16INK4a蛋白表达降低、MDM2蛋白表达增高可能在PTC发生发展中起重要作用,联合检测有助于PTC生物学行为的判定。     

食管癌组织中p53、HPV的表达变化及意义

目的观察食管癌组织中p53、人乳头瘤病毒（HPV）的表达变化,并探讨其意义。方法取45例食管癌患者肿瘤组织组织（食管癌组）、20例食道良性肿瘤患者肿瘤组织（良性肿瘤组）、20例食管正常者的食管组织（对照组）,采用ELISA法检测其中p53蛋白,采用新柏式液基细胞学技术（TCT）检测HPV。结果食管癌组44例p53表达阳性、40例HPV阳性,良性肿瘤组分别为2、2例,对照组分别为1、1例,食管癌组p53、HPV阳性表达率与良性肿瘤组和正常组相比P均〈0.01,良性肿瘤组与对照组相比P〉0.05。食管癌组织中HPV、p53表达呈正相关（r=0.429,P〈0.05）。结论食管癌组织中p53、HPV表达升高。检测HPV、p53有助于食管癌早期诊断。     

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.     

PTEN和突变型p53蛋白在鼻咽癌组织中的表达及临床意义

采用免疫组化EnVision法,分别检测72例鼻咽癌和32例鼻咽黏膜慢性炎性组织中蛋白酪氨酸磷酸酶基因（PTEN）及突变型p53蛋白的表达情况,分析二者与鼻咽癌临床病理特征的相关性。结果PTEN、突变型p53蛋白阳性表达率在鼻咽癌组织中分别为45．8％、77．8％,在鼻咽黏膜慢性炎性组织中分别为87．5％、9．4％,P均〈0．05;二者在鼻咽癌组织中的表达呈负相关性,且与鼻咽癌临床分期及淋巴结转移相关（P〈0．05）。证实在鼻咽癌组织中存在PTEN蛋白低表达和突变型p53蛋白高表达,且二者呈负相关,此在鼻咽癌发生、发展和转移中起重要作用。     

胃癌组织mdm2、p53及p21蛋白表达与EB病毒感染的关系

应用免疫组化技术检测13例EB病毒相关胃癌（EBVaGC）（观察组）组织中mdm2、p53和p21蛋白的表达,并与45例EB病毒阴性胃癌（EBVnGC）（对照组）进行比较,发现两组mdm2、p53和p21蛋白的阳性检出率无明显差异（P均〉0．05）,但观察组p53蛋白过表达率（15．38％）明显低于对照组（57．78％）,P〈0．01。观察组核抗原基因EBNA1均为阳性,潜伏膜蛋白基因LMP1均为阴性,即刻早期基因BZLF1、早期基因BARF1和BHRF1阳性率分别为46．15％、46．15％和15．38％,三者与mdm2、p21和p53蛋白的表达均无显著相关性（P〉0．05）。提示胃癌组织中病毒感染与p53蛋白的异常表达有关,而与mdm2和p21蛋白的异常表达无相关性。     

食管癌组织芯片p53、p16和环氧合酶-2表达的研究

目的食管癌的发生发展是多步骤、多基因变化的演化过程，本研究利用高通量的组织芯片技术，对食管癌组织及癌旁组织的p53、p16和环氧合酶（COX）-2蛋白异常表达进行分析，探讨其相关性及临床意义。方法利用组织芯片技术结合免疫组化法检测86例食管癌组织、40例癌旁组织中p53、p16、COX-2蛋白的表达。结果食管癌组织中p53、COX-2的阳性表达率均显著高于癌旁组织（P〈0．05）。食管癌组织中p16阳性表达率为5．81％，癌旁组织中没有发现p16蛋白表达，差异无统计学意义。p53与p16、p53与COX-2、p16与COX-2蛋白表达均存在差异（P〈0.05）。p53或COX-2表达阳性时组织芯片病理类型为癌性的概率增加，但p16、p53和COX-2三者不存在交互作用。结论p53、COX-2对预测和早期诊断食管癌具有重要意义。     

Survivin、p53基因在脑胶质瘤组织的表达

应用免疫组织化学方法，检测Survivin和p53基因在120例胶质瘤组织（WHOⅠ级40例，WHOⅡ级40例，WHOⅢ～Ⅳ级40例）和17例正常脑组织组织的表达。结果120例胶质瘤Survivin、突变型p53基因的阳性表达率为52．5％、45．8％，17例正常脑组织中Survivin、突变型p53基因不表达，差别有统计学意义（P〈0.05）;随肿瘤分化程度降低，突变型p53和Survivin基因表达率逐渐升高（P〈0．05），Survivin与突变型p53基因的表达呈正相关（P〈0．01）.     

p16及p53蛋白在前列腺癌中的表达及意义

目的探讨p16及p53蛋白在前列腺癌中的表达及意义。方法应用免疫组化方法检测p16及p53蛋白在58例前列腺癌和20例良性前列腺增生症中的表达状况。结果p16在前列腺癌中阳性率为72．4％，在前列腺增生症中的阳性率为25．0％，两组差异有有统计学意义（P〈0．01）。p53在前列腺癌中的阳性率为29．3％，在前列腺增生症中的阳性率为15．0％、染色强度弱于前列腺癌，两组阳性率无统计学差异。053表达与Gleason评分呈正相关（r=0．334，P=0．011）。结论p53及p16可能与前列腺癌的发生有关。     

MEK通路抑制剂对人胰腺癌细胞生长及细胞周期相关抑癌基因表达的影响

目的 观察细胞外信号调节激酶信号通路(MEK)抑制剂对人胰腺癌细胞生长及细胞周期相关的抑癌基因表达的影响。方法 培养人胰腺癌细胞系CFPAC1、PANC1和MiaPaCa2,应用50μmol/L的MEK抑制剂PD98059处理细胞24h,四甲基偶氮唑蓝(MTT)法检测细胞增殖,流式细胞仪分析细胞周期,实时定量PCR法检测p16INK4a、p21 WAF1和p27KIP1 mRNA的表达,蛋白质印迹法检测DNA甲基化酶(Dnmt)1、3a和3b表达,甲基化特异性PCR(MSP)分析p16INK4a基因启动子甲基化状况。结果 PD98059处理24h后,CFPAC1、PANC1和MiaPaCa2细胞的增殖抑制率分别为69％、78％和45％;G0/G1期细胞比例分别从(68.21±0.73)％、(56.54±0.68)％、(54.89±0.79)％增加到(80.37±0.65)％、(72.05±0.52)％、(79.21±0.93)％(P值均＜0.05);S期和G2/M期细胞比例相应减少。PD98059处理后,CFPAC1、PANC1细胞p27KIP1、p21WAF1和p16INK4a mRNA表达增加,Dnmt1和Dnmt3b蛋白表达减少;p16INK4a启动子甲基化状态被去除。而MiaPaCa2细胞仅p27KIP1 mRNA表达增加;p21WAF1、p16INK4a mRNA和Dnmt表达均无明显变化。结论 MEK通路抑制剂可能通过下调DNA甲基化酶、上调细胞周期相关抑癌基因表达而抑制胰腺癌细胞周期进展和细胞增殖。     

Frequent alterations in the expression of tumor suppressor genes p16INK4A and pRb in esophageal squamous cell carcinoma in the Indian population

PURPOSE: Alterations in the cell cycle regulatory p16INK4a/Cyclin D1/pRb pathway play a pivotal role in tumorigenesis. Knowledge of alterations in the tumor suppressor protein pRb and its negative regulator, p16CDKN2/MTS1/INK4a in esophageal squamous cell carcinoma (ESCC) from the Indian subcontinent is meager. To gain insight into the mechanisms underlying tumorigenesis and to search for diagnostic molecular markers for ESCC, we analyzed the expression of p16INK4a and pRb in ESCCs in the Indian population. METHODS: Immunohistochemical analysis of pRb and p16INK4a proteins was carried out in paraffin-embedded sections from 61 surgically resected ESCCs and matched normal tissues, and the results correlated with clinicopathological parameters using chi square and Fisher's exact tests. Dual immunohistochemical analysis has been carried out to demonstrate the concomitant loss of expression of p16INK4a and pRb. RESULTS: Fifty-nine of 61 (97%) cases showed aberration(s) in either or both of these proteins confirming their critical role in esophageal tumorigenesis. Loss of pRb was observed in 51 of the 61 (84%) and loss of p16INK4a was observed in 35 of 61 (57%) cases. Loss of pRb showed significant association with dedifferentiation of the tumor (P = 0.004). p16-/pRb-, and p16+/pRb- phenotypes were significantly associated with nodal metastasis (P = 0.017 and 0.027, respectively), while p16-/pRb+ phenotype was associated with dedifferentiation of the tumor (P = 0.012). CONCLUSION: pRb/p16INK4a pathway plays a critical role in esophageal tumorigenesis in the Indian population. The dual hits (concomitant loss) of pRb and p16INK4a expression suggest that these two components are not mutually exclusive, and can both be altered in a significant proportion of primary ESCCs serving as putative diagnostic markers for esophageal cancer. However, the impact of dual hit on tumor behavior and disease prognosis remains to be determined.     

Deregulation of G1/S transition is a common event in carcinoma of the ampulla of vater

BACKGROUND/AIMS: Aberrant expression of cell cycle regulators and subsequent deregulation of G1/S transition is one of the most important characteristics of human cancer. The aim of this study was to determine the overall pattern of deranged expression of the cell cycle regulators involved in the G1/S transition in ampullary carcinoma. METHODOLOGY: Using immunohistochemistry, we investigated the expression of p21WAF1/CIP1, p27Kip1, p16INK4, cyclin D1, cyclin E, pRb and p53 in 14 resected specimens of ampullary carcinoma and defined the proliferative activity of each tumor by quantifying Ki-67 antigen. RESULTS: Decreased expression of p21WAF1/CIP1, p27Kip1, and p16INK4 was detected in 6 (43%), 11 (79%), and 4 (29%) tumors, respectively. Four tumors (29%) overexpressed cyclin D1 and 8 (57%) overexpressed cyclin E. Eight tumors (57%) overexpressed pRb. Aberrant accumulation of p53 was observed in 10 (71%) of the tumors. Overall, the expression of two or more of these cell cycle regulators was altered in all of the 14 tumors. Decreased p21WAF1/CIP1 expression was related to higher TMN stage (P = 0.04) and lymphatic invasion (P = 0.04). The proliferative index was higher in tumors with decreased p27Kip expression (P = 0.005), and in tumors with cyclin E overexpression (P = 0.06). CONCLUSIONS: Our observations suggest that deregulation of G1/S transition is a very common event in ampullary carcinoma, and that altered expression of cell cycle regulators is associated with the aggressive behavior of this tumor. Correcting the G1/S transition regulatory machinery may provide a novel therapy for this malignancy.     

Human papillomavirus DNA and P16(INK4A) expression in concurrent esophageal and gastric cardia cancers

AIM:To investigate the relationship between human papillomavirus (HPV) infection and concurrent esophagus and gastric cardia cancer from the same patient (CC) and examine the significance of P16 INK4A protein expression.METHODS:Polymerase chain reaction was used to detect the presence of HPV type16 (HPV16).The expression of P16 INK4A protein was detected using immunohistochemistry.RESULTS:Among the CC specimens,HPV16-DNA was found in eight cases of esophageal squamous cell carcinoma (ESCC) and five cases of gastric cardia adenocarcinoma (GCA),respectively (47% vs 29%),and two of both ESCC and GCA.P16 INK4A was highly expressed in both ESCC and GCA.In the HPV-associated positive CC,higher P16 INK4A expression was observed in the GCA than in the ESCC (75% vs 25%,P < 0.05).CONCLUSION:HPV16 as a correlated risk factor may play an important role in the development of ESCC and GCA.P16 INK4A may be a screening index in the HPVassociated carcinoma of gastric cardia.     

Expression of thymidylate synthase in human gastric and colorectal adenocarcinomas is upregulated by p16/INK4

BACKGROUND/AIMS: We observed the relationship between the expression of thymidylate synthase protein (pTS) and cell cycle regulators in gastric and colorectal adenocarcinoma tissues. METHODOLOGY: This study included 80 gastric and 50 colorectal adenocarcinomas. Immunohistochemical staining was performed using a polyclonal antibody to recombinant human pTS, and monoclonal antibodies to p53, p21/WAF1CIP1, p16/INK4, cyclin D1 and pRB. Each staining was quantified using computerized image analysis on a CAS 200 system. We selected the mean expression values as the cutoff values to distinguish between high and low expression of these substances. RESULTS: There was no relationship between pTS expression and p21/WAF1CIP1, cyclin D1, or pRB expression in gastric and colorectal carcinomas. In both gastric and colorectal carcinomas, the pTS expression was significantly low in the high p16/INK4 expression subgroup compared with the low p16/INK4 expression subgroup (P < 0.05). Further, the pTS expression was significantly high in the high p53 expression subgroup compared with the low p53 expression subgroup in colorectal adenocarcinomas (P < 0.05). CONCLUSIONS: pTS expression regulation in human gastric and colorectal adenocarcinomas in complex, and upregulated by p16/INK4.     

原发性肝细胞癌中WAF1／CIP1基因的及其与p53基因突变的关系

目的 研究原发性肝细胞癌（ＨＣＣ）组织中ＷＡＦ１基因的表达及其与ｐ５３基因突变和临床病理学指标的关系和意义。方法 应用半定量ＲＴ－ＰＣＲ、免疫组织化学及定量ＤＮＡ图像分析的方法,检测ＷＡＦ１基因在３２例ＨＣＣ及其癌旁肝组织和５例正常肝细胞中的表达,研究其与ｐ５３基因突变及临床病理学指标的关系。结果 肝癌组织中ＷＡＦ１ｍＲＮＡ表达相对值（１．０６±０．３７）Ｕ低于其相应旁旁肝组织（１．３０±０．３７     

P21/WAF1 is an independent survival prognostic factor for patients with hepatocellular carcinoma after resection.

BACKGROUND/AIMS: The cyclin kinase inhibitor p21/WAF1 is regulated by p53-dependent or independent pathways and inhibits the action of proliferating cell nuclear antigen (PCNA). The prognostic role of p21/WAF1 in hepatocellular carcinoma (HCC) is ambiguous. To further clarify this, we examined the expression of three genes in HCC. METHODS: A total of 122 resected HCC specimens were collected from 1987 to 1998. Expression of p21/WAF1, p53, and PCNA in HCC was analysed by immunohistochemistry. RESULTS: Immunoreactivity was detectable for p21/WAF1 in 37%, and for p53 in 41.8% of HCCs. Positive expression of both genes does not relate to each other, but both are associated with a high PCNA labelling index (LI) (P<0.05) in tumour. p53 (+) is also associated with high serum alpha-foetoprotein (alphaFP) (P<0.001), tumour dedifferentiation (P=0.001) and advanced pathologic stages (P=0.017). However, p21/WAF1 (+) did not show clinicopathologic significance. Survival analysis indicated that poor prognostic factors were p21/WAF1 (-) (P=0.024), p53 (+) (P=0.008), high PCNA (P<0.001), tumour without capsule (P=0.001), poor tumour differentiation (P=0.004), advanced pathologic stage (P<0.001), and high serum alphaFP(P<0.001). Independent factors were p21/WAF1 expression, pathologic stage, and PCNA. CONCLUSION: In HCC, increased proliferation index PCNA is significantly associated with positive p53 and p21/WAF1. But p21/WAF1 expression did not relate to p53 expression. P21/WAF1 (+) is a good event and serves as an independent survival prognostic factor for HCC, which is a novel finding apart from previous reports.     

Expression of p53 and p21WAF1/CIP1 Proteins in Gastric and Esophageal Cancers (Comparison with Mutations of the p53 Gene)

The p53 gene has been shown to be commonlymutated in various human cancers, and mutant p53 can actas a dominant oncogene. The intact p53 protein is alsoknown to induce the cyclin-dependent kinase inhibitor p21^WAF1/CIP1 and is implicated incell cycle arrest. We investigated p53 gene alterationsin gastric adenocarcinoma and esophageal squamous cellcarcinoma to elucidate the association of the nuclearaccumulation of the p53 protein and/orp21^WAF1/CIP1 protein. Abnormalities of thetumor suppressor gene p53 protein and the expression ofp21^WAF1/CIP1 protein were analyzed byimmunohistochemical techniques in 32 cases of gastric adenocarcinoma and 15 cases ofesophageal squamous cell carcinoma. Twenty cases ofgastric cancer and five cases of esophageal cancer werealso analyzed for p53 gene mutation by polymerase chain reaction and direct nucleotide sequencing.Overexpression of p53 protein was found in 13/32 (41%)of gastric cancers and 5/15 (33%) of esophageal cancers.We found immunodetectable p53 in 10/14 cases with mutations and in none of 11 cases withoutmutations in gastric and esophageal cancers. Hence,immunohistochemical and genetic analyses gave concordantresults in 84% of 25 cases, revealing a good correlation between immunostaining of p53 and missensemutation of the p53 gene. p53 immunostaining was notobserved in cases with frameshift or splicing mutation.The expression of p21^WAF1/CIP1 protein wasfound in 9/32 (29%) of gastric cancers and 4/15 (27%) ofesophageal cancers and in 2/14 (14%) cases withalteration of the p53 gene and in 5/11 (45%) without.These results suggest that abnormalities of p53 may be closely associated with the pathogenesisof gastric adenocarcinoma and esophageal squamous cellcarcinoma and that the immunoreactivity of p53 proteinis a general indicator of the tumors with altered p53 function. The expression ofp21^WAF1/CIP1 protein was suppressed in theneoplastic tissues with and without p53 genealteration.     

Long-term cultured IL-2-dependent T cell lines demonstrate p16(INK4a) overexpression, normal pRb/p53, and upregulation of cyclins E or D2

Acquisition of an immortal phenotype by circumvention of the normal senescence program can be an important step in tumor development and progression. The regulation of life-span checkpoints is complex and abrogation of these processes can occur at different levels. To better understand these mechanisms in long-term cultured lymphocytes we have characterized two human long-term cultured IL-2-dependent T cell lines regarding telomere length, telomerase activity, and the expression of selected cell cycle regulators (pRb, p53, cyclin E, cyclin D1, cyclin D2, cyclin D3, cdk4, p16(INK4a), p21(WAF1), p27(KIP1), c-myc, bcl-2, and NPAT). We compared these cell lines with a primary T lymphoblast population with a limited life span from the same donor. Both T cell lines with extraordinary growth capacity showed telomere length stabilization, high telomerase activity and demonstrated wild-type pattern of pRb and p53 but strong p16(INK4a) protein expression. The growth inhibitory activity of p16(INK4a) seemed to be abrogated by enhanced expression of cyclin D2, cdk4, and c-myc in one T cell line and overexpression of cyclin E in the second T cell line.