大肠癌组织中p73、p51的相关性研究

目的:研究大肠癌组织中p73,p51基因的表达情况及其临床意义。方法:采用逆转录聚合酶链反应技术(RT-PCR),检测30例大肠癌组织及邻近正常大肠粘膜组织p73及p51的两个转录p51A、p51BmRNA表达情况。结果:30例大肠癌组织中有22例p73表达阳性,相对应的正常大肠组织仅有3例表达阳性,两者具有显著性差异(P<0.01),大肠癌组织的p73阳性表达率与大肠癌的分化程度及TNM分期均无关(P>0.05);p51A、p51B在30例大肠癌组织和相对应的正常大肠组织呈低水平表达,其中大肠癌组织中p51A表达量明显高于正常大肠组织(P<0.01),与细胞分化程度及TNM分期无关(P>0.05),而p51B在大肠癌组织和正常大肠组织中的表达量无明显差异(P>0.05)。结论:大肠癌组织中存在p73、p51A的过度转录表达,p73、p51A的过度表达与大肠癌的发生发展存在一定的关系。     

大肠癌组织中p73、p51的相关性研究

目的：研究大肠癌组织中p73,p51基因的表达情况及其临床意义。方法：采用逆转录聚合酶链反应技术（RT-PCR）,检测30例大肠癌组织及邻近正常大肠粘膜组织p73及p51的两个转录p51A、p51BmRNA表达情况。结果：30例大肠癌组织中有22例p73表达阳性,相对应的正常大肠组织仅有3例表达阳性,两者具有显著性差异（P〈0.01）,大肠癌组织的p73阳性表达率与大肠癌的分化程度及TNM分期均无关（P〉0.05）;p51A、p51B在30例大肠癌组织和相对应的正常大肠组织呈低水平表达,其中大肠癌组织中p51A表达量明显高于正常大肠组织（P〈0.01）,与细胞分化程度及TNM分期无关（P〉0.05）,而p51B在大肠癌组织和正常大肠组织中的表达量无明显差异（P〉0.05）。结论：大肠癌组织中存在p73、p51A的过度转录表达,p73、p51A的过度表达与大肠癌的发生发展存在一定的关系。     

p73基因在食管癌中的转录表达及其意义

目的：检测p73 mRNA在食管癌中的表达情况，探讨p73基因在食管癌发生、发展中的角色和作用机制。方法：采用逆转录多聚酶链反应技术（RT－PCR）检测37例食管鳞状细胞癌肿瘤组织、癌旁组织、区域淋巴结和相应正常食管组织中p73 mRNA的转录表达，并探其与食管癌临床病理特性的关系。结果：37例食管肿瘤组织中有21例（15．8％）p73 mRNA过度表达，其过度表达率显著高于相应的癌旁组织、区域淋巴结和正常组织（P＜0．05），但与食管癌TNM分期、细胞分化程度和病理类型均无明显关系（P＞0．05）。结论：食管肿瘤组织中存在p73基因的过度转录表达，可能参与了调控食管癌的发生过程，它的存在并没有阻止食管癌的进展，在食管癌中可能没有担当起主要的抑癌作用。     

人肺癌组织端粒酶活性与p16基因二者相关性探讨

目的:探讨非小细胞肺癌(NSCLC)组织中端粒酶活性与p16基因的相关性及二者与肺癌发生发展的关系.方法:肺癌标本48例,12例癌旁组织,7例非肿瘤病例的正常肺组织.以Telomerase PCR ELISA检测标本端粒酶活性,以RT-PCR的方法检测p16基因mRNA转录情况,以免疫组化方法检测组织标本p16蛋白表达.结果:1)肺癌组织标本36/48(75.00%)和1例癌旁组织检出端粒酶活性.2)48例NSCLC组织中32例进行了p16 mRNA及蛋白表达检测.16/32(50.00%)检测到p16mRNA转录,7例正常组织中均检测到p16 mRNA转录.NSCLC组织标本中17/32(53.13%)未检测到p16蛋白表达,7例正常肺组织中均检测到p16蛋白表达.3)24例端粒酶阳性NSCLC组织中15例p16 mRNA表达缺失,8例端粒酶阴性的NSCLC组织中仅1例p16mRNA表达缺失.相关系数为-0.433,P=0.013,具有显著负相关.结论:端粒酶、p16基因在NSCLC的发生发展中起重要作用,端粒酶活性有望成为预测肿瘤发生、肿瘤诊断的良好指标.端粒、端粒酶与p16基因可能成为抗肿瘤治疗的新靶点.     

胃癌组织p73基因突变与p21waf2蛋白的检测分析

[目的]探讨胃癌组织中p73基因突变与p21waf2蛋白表达的相关性及其在胃癌发生、发展中的作用.[方法]采用PCR_SSCP及免疫组织化学法,检测60例胃癌新鲜手术标本中癌组织和相应的胃正常粘膜组织p73突变及p21waf2蛋白的表达.[结果]p73突变检出率,在60例胃癌组织中为53.33%(32/60),在相应的胃正常粘膜组织中为1.67%(1/60),差异有显著性(P<0.01);其中25例有淋巴结转移者,p73突变检出率为92.00%(23/25),无淋巴结转移者为25.71%(9/35),差异有非常显著性(P<0.005).p21waf2蛋白检测阳性率,在60例胃癌组织中为33.33%(20/60),在相应的胃正常粘膜组织中为86.67%(52/60),有显著性差异(P<0.01);其中25例有淋巴结转移者,p21waf2蛋白阳性率为4.00%(1/25),无淋巴结转移者为53.45%(19/35),差异有显著性(P<0.01).[结论]胃癌组织中,p73基因突变与p21waf2蛋白低表达有显著的相关性,并与胃癌的发生和胃周淋巴结转移相关,其临床意义值得进一步探讨.     

喉鳞癌中p73、p63的表达及其临床意义

目的:探讨p73、p63在喉鳞癌(LSCC)组织中的表达及与喉鳞癌发生、发展的关系和生物学意义。方法:应用原位分子杂交方法,检测p73mRNA、p63mRNA在47例喉鳞癌组织、癌旁组织及14例正常喉组织中的表达。结果:p73在正常喉组织中不表达;在喉癌组织、癌旁组织中的阳性表达率分别为57.4%(27/47)、29.8%(14/47),分别与正常喉组织比较,差异有统计学意义(P<0.05);组织分化程度越低、TNM分期越晚、淋巴结转移率越高,则p73 mRNA表达越强(均P<0.05)。p63在喉鳞癌、癌旁组织中的阳性表达率为91.5%(43/47)、93.6%(44/47)、分别与正常喉组织(57.1%)比较,差异有统计学意义(P<0.05);p63与喉癌临床病理特征无关。结论:p73表达有助于判断喉鳞癌的生物学行为和预后。p63对LSCC生物学行为的影响较小。     

胃癌中p21WAF1/CIP1、细胞周期素D1、p53表达的相关性

目的　探讨p2 1WAF1/CIP1、细胞周期素D1(cyclinD1)、p5 3在胃癌中表达之间的相关性。 方法　应用原位杂交技术检测p2 1WAF1/CIP1mRNA、细胞周期素D1mRNA及免疫组化技术检测p5 3蛋白在胃癌中的表达。结果　p2 1WAF1/CIP1mRNA在癌组织及癌旁正常粘膜中阳性表达率各为 93.15 % (6 8/73)及76 .71% (5 6 /73) ,二者相比具有显著差异 (P <0 .0 5 )。CyclinD1mRNA在癌组织及癌旁正常粘膜中阳性表达率各为 5 4 .79% (40 /73)及 30 .16 % (2 2 /73) ,二者具有显著差异 (P <0 .0 5 )。p5 3蛋白在胃癌中的阳性表达率为 32 .87% (2 4 /73) ,p5 3过表达者 ,其 p2 1WAF1/CIP1mRNA表达较p5 3阴性者为低 ,二者存在显著差异 (P <0 .0 5 )。p2 1WAF1/CIP1表达与细胞周期素D1表达呈负相关。结论　p2 1WAF1/CIP1、CyclinD1、p5 3的异常表达及它们之间可能存在的相互作用 ,对于胃癌的发生发展具有重要意义。     

胃癌中p21WAF1/CIP1、细胞周期素D1、p53表达的相关性

目的探讨p21WAF1/CIP1、细胞周期素D1(cyclin D1)、p53在胃癌中表达之间的相关性.方法应用原位杂交技术检测p21WAF1/CIP1 mRNA、细胞周期素D1 mRNA及免疫组化技术检测p53蛋白在胃癌中的表达.结果 p21WAF1/CIP1 mRNA在癌组织及癌旁正常粘膜中阳性表达率各为93.15%(68/73)及76.71%(56/73),二者相比具有显著差异(P<0.05).Cyclin D1 mRNA在癌组织及癌旁正常粘膜中阳性表达率各为54.79%(40/73)及30.16%(22/73),二者具有显著差异(P<0.05).p53蛋白在胃癌中的阳性表达率为32.87%(24/73), p53过表达者,其p21WAF1/CIP1 mRNA表达较p53阴性者为低,二者存在显著差异(P<0.05).p21WAF1/CIP1表达与细胞周期素D1表达呈负相关.结论 p21WAF1/CIP1、Cyclin D1、p53的异常表达及它们之间可能存在的相互作用,对于胃癌的发生发展具有重要意义.     

非小细胞肺癌p73基因突变与表达的研究

[目的]研究p73基因在非小细胞啼癌中的突变及表达情况，分析其与非小细胞肺癌的临床分期、组织学分型的相关性，探讨p73与肺癌发生、发展的关系．[方法]应用催化信号放大（CSA）法检测40例非小细胞肺癌患者癌组织及癌旁组织p73蛋白表达；酚-氯仿-异戊醇法提取基因组DNA，应用PCR—SSCP法（单链构象多态性分析）检测p73基因突变，并对出现异常条带样本进行DNA测序分析．[结果]40例非小细胞肺癌组织中p73阳性表达率52．5％（21／40）明显高于癌旁肺组织（0）（P〈0．005）。p73阳性表达率与肿瘤临床分期、组织学分型有相关性（P〈0．01）。有3例p73基因第2位外显子序列存在遗传多态性，碱基T→C置换、[结论]p73在非小细胞肺癌组织中存在过度表达及遗传多态性，D73可能参与调控非小细胞肺癌的发生、发展过程．     

胃癌组织中p16基因甲基化状态及临床意义

[目的]探讨胃癌患者癌组织、癌旁组织以及对照正常胃黏膜组织中p16基因的甲基化状态,及其与临床病理参数及预后的关系。[方法]应用甲基化特异性实时荧光聚合酶链反应技术检测92例胃癌患者癌组织及配对癌旁组织中p16基因启动子区5′-CpG岛甲基化状态,分析p16基因异常甲基化与患者临床病理特征以及预后之间的关系。[结果]胃腺癌患者癌组织中检测到p16基因甲基化79例(85.9%),癌旁组织11例(12.0%),胃炎患者组织10例(20.8%),健康人未检测到甲基化。p16基因甲基化与肿瘤大小、分化程度、是否淋巴管侵犯、T分期、有无淋巴结转移、有无远处转移、临床分期有关(P<0.05)。p16基因甲基化影响患者预后,但不是胃癌患者无病生存的独立预后因子。[结论]胃腺癌患者p16基因甲基化与肿瘤的生物学行为有关,提示肿瘤进展,恶性程度高,预后欠佳。     

INK4系列抑癌基因在白血病中纯合子缺失的实验研究

目的：探讨p16基因家族失活与白血病发生、发展及预后的关系。方法：PCR检测p16、p15、p18、p19基因在白血病中纯合子缺失。结果：p16、p15基因外显子1在AL组纯合子缺失率分别为22．37％、17．05％,在ALL组为45．95％、32．43％,在ANLL组均为5．88％;在CML的慢性期均为0。p16、p15基因外显子2在AL组纯合子缺失率分别为12．5％、5．68％;在ALL组为24．32％、10．81％;在ANLL组为3．92％、1．96％;在CML和对照组二者均无缺失。p18、p19基因外显子1在AL组纯合子缺失率分别为1．14％、0;在ALL组分别为2．70％、0;在ANLL和对照组均无缺失。结论：p16、p15基因纯合子缺失在AL的发生频率较高,ALL缺失率明显高于ANLL,复发一LLL组基因失活率最高。p16、p15基因纯合子缺失是AL,尤其是ALL的发病重要因素之一。p18、p19基因在AL组中几乎未见纯合子缺失。在ALL中,p16纯合子缺失率高于p15纯合子缺失率。两个基因的纯合子缺失常伴随存在。在ANLL中,p16、p15基因的纯合子缺失均少见。     

p29ING4 and p28ING5 bind to p53 and p300, and enhance p53 activity

We identified and characterized two new ING family genes, p29ING4 and p28ING5,coding for two proteins of 249 and 240 amino acids, respectively. Both p29ING4 and p28ING5 proteins have a plant homeodomain finger motif also found in other ING proteins, and which is common in proteins involved in chromatin remodeling. p29ING4 or p28ING5 overexpression resulted in a diminished colony-forming efficiency, a decreased cell population in S phase, and the induction of apoptosis in a p53-dependent manner. Both p29ING4 and p28ING5 activate the p21/waf1 promoter, and induce p21/WAF1 expression. p29ING4 and p28ING5 enhance p53 acetylation at Lys-382 residues, and physically interact with p300, a member of histone acetyl transferase complexes, and p53 in vivo. These results indicate that p29ING4 and p28ING5 may be significant modulators of p53 function.     

p53基因家族的新成员 p73和 p63

p53作为广泛存在的肿瘤抑制基因,最近发现了其家族成员：p73和p63。它们在结构和功能上具有相似性,均能触发细胞周期停滞,诱导凋亡,但它们在肿瘤抑制和组织发育中起着截然不同的作用,深入了解它们彼此之间的相似性和差异将对理解肿瘤发生的机制产生重要的影响。本文总结了最近几年来此领域内的最新进展。另外,p73和p63在C端的SAM结构说明它们可能参与组织的发育过程。     

INK4系列抑癌基因纯合子缺失、甲基化与白血病预后的实验研究

 目的　研究INK4系列抑癌基因纯合子缺失、甲基化与白血病预后的关系。方法　采用聚合酶链反应（PCR）研究p16基因家族在白血病中纯合子缺失,应用甲基化敏感限制内切酶HpaⅡ结合PCR技术研究白血病患者p16、p15、p18、p19 基因甲基化状况,用单因素、多因素Logistic回归分析其基因失活与急性白血病（AL）预后的关系。结果　基因表达组治疗有效27例（84.38 %）,基因失活组治疗有效11例（28.95 %）,基因表达组治疗有效率明显高于基因失活组（P＜0.001）。单因素、多因素Logistic回归分析结果显示p16、p15 基因失活化疗有效率明显低于基因表达组。结论　p16、p15基因失活可作为AL病程进展、复发、预后的指标之一。     

NBP is the p53 homolog p63

We previously identified a non-p53, p53-responsive DNA element (p53RE)-binding protein named NBP, functionally analogous to p53, from human cervical carcinoma Hela cells. Here we report a biochemical study demonstrating that this activity is the recently cloned p53 analog p63. NBP was purified through conventional and DNA affinity chromatography to apparent homogeneity with a prominent polypeptide migrating in between the 43 and 68 kDa positions on a SDS gel. This polypeptide immunoreacted with monoclonal anti-p63 but not anti-p53 or anti-p73 antibodies. Also, NBP co-purified with p63 through each step of fractionation, as detected with anti-p63 antibodies. DNA-protein complexes formed with purified NBP and p53RE-containing oligomers derived from the p21(waf1) promoter were supershifted by anti-p63 but not anti-p53 antibodies. Thus, these results demonstrate that NBP is encoded by the p53 homolog p63 gene.     

Tumorigenesis in p27/p53- and p18/p53-double null mice: functional collaboration between the pRb and p53 pathways

Mice lacking both p18(Ink4c) and p27(Kip1) develop a tumor spectrum similar to pRb(+/-) mice, and loss of p53 function accelerates tumorigenesis in pRb(+/-) mice. We hypothesized that codeletion of either p18 or p27 in conjunction with p53 deletion will also accelerate tumorigenesis. Mice lacking both p18 and p53 develop several tumors not reported in either single null genotype, including hepatocellular carcinoma, testicular choriocarcinoma, hemangiosarcoma, leiomyosarcoma, fibrosarcoma, and osteosarcoma. Mice lacking both p27 and p53 exhibit a decreased lifespan and develop unique tumors, including papillary carcinoma of the colon, hemangiosarcoma, and leiomyosarcoma. In both p18/p53 and p27/p53 double null genotypes, the incidence and spectra of tissues that develop lymphoma are also increased, as compared to the single null genotypes. The development of p27/p53 double null colon tumors correlates with secondary changes in cell-cycle protein expression and CDK (cyclin-dependent kinase) activity, perhaps contributing to the progression of colorectal cancer. We concluded that p18 and p27 can, not only functionally collaborate with one another, but also can independently collaborate with p53 to modulate the cell cycle and suppress tumorigenesis in a tissue-specific manner.     

原发性肝细胞癌中p21WAF1及p16INK4a 的表达与HBV的关系

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A Comparative Study of Glioma Cell Lines for p16, p15, p53 and p21 Gene Alterations

A total of 10 glioma cell lines were examined for alterations of the p16, p15, p53 and p21 genes, which are tumor suppressor genes or candidates with direct or indirect CDK-inhibitory functions. Genetic alterations (deletions or mutations) were frequently seen in the p16, p15 and p53 genes in these cell lines, but not in the p21 gene. When the states of the p16, p15 and p53 genes were compared among cell lines, all the cell lines showed abnormalities in at least 1 gene, often in 2 or 3 genes coincidentally, suggesting that dysfunction of these genes is closely related to glioma cell growth. Although alteration of all 3 genes was most frequent, there were cell lines having either p16/p15 or p53 or p16 and p53 gene alterations, suggesting that the time order of these genetic alterations was variable depending on the cell line. Among cell lines examined, one with homozygous p53 gene deletion seemed of particular practical value, since such a cell line might be useful in various studies, including investigation of the functions of various mutant p53 genes in the absence of heteromeric protein formation. On examination of the primary tumor tissues, the same alterations of the p16/p15 and p53 genes as detected in the cell lines were demonstrated in all 6 cases examined: p16/p15 gene deletion in 1, p16 gene mutation in 1 and p53 gene mutations in 5 cases. This suggested that the p16/p15 and the p53 gene alterations and their combinations in at least some glioma cell lines reflected those in the primary glioma tissues.     

Role of p53 family members p73 and p63 in human hematological malignancies

Abstract p53, mutated in over half of human cancers and about 13% of all hematological malignancies, maintains genomic integrity and triggers cellular senescence and apoptosis of damaged cells. In contrast to p53, the homologs p73 and p63 play critical roles in development of the central nervous system and skin/limbs, respectively. Moreover, dependent on the context they can exert tumor suppressor activities that cooperate with p53. Unlike p53, p73 and p63 are rarely mutated in cancers. Instead, up-regulation of the anti-apoptotic dominant-negative ΔNp73 and ΔNp63 isoforms is the most frequent abnormality in solid cancers. In hematological malignancies the most frequent p73 defect is promoter methylation and loss of expression, associated with unfavorable clinical outcomes. This suggests an essential tumor suppressor role of p73 in blood cells, also supported by genetic mouse models. Many therapeutic approaches aiming to restore p73 activity are currently being investigated. In contrast, the most frequent p63 abnormality is protein overexpression, associated with higher disease grade and poorer prognosis. Surprisingly, although available data are still scarce, the emerging picture is up-regulation of transactivation-competent TAp63 isoforms, suggesting a tumor-promoting role in this context.