c—erbB—2,ras,p53基因产物在大肠癌及癌前病变中的表达

目的：探讨ｃ－ｅｒｂＢ－２、ｒａｓ、ｐ５３基因的表达与大肠癌发生发展的关系以及其对大肠癌早期诊断、预后判断的价值。方法：对４５例大肠癌及３６例癌旁非腺瘤型不典型增生、１７例大肠腺瘤，用免疫组化方法检测基因产物的表达。结果：ｐ５３在大肠癌的阳性表达率为５７．８％，ｐ５３蛋白高表达的癌旁非腺瘤型不典型增生及大肠腺瘤均为中度或高度不典型增生。ｐ５３蛋白表达与大肠癌的组织分化程度、淋巴结转移有关（Ｐ〈０．     

大肠癌中PCNA、p53和C—erbB—2的表达及与机体免疫反应的关系

目的：观察大肠癌和癌旁粘膜中PCNA、p53和C－erbB-2的表达及与机体免疫反应的关系。方法：用免疫组化Envision法检测42例大肠癌组织、35例癌旁及10例正常粘膜中PCNA、p53和C－erbB-2的表达,观察切片中纤维增生、单个核细胞浸润、淋巴结反应情况、以反映机体的免疫反应,并分析与PCNA、p53和C－erbB-2表达的关系。结果：（1）大肠癌中PCNA、p53和C－erbB-2的表达显著高于政党大肠粘膜,且癌组织PCNA的强阳性率高于p53和C－erbB-2（P＜0．05）。（2）p53强阳性者淋巴结生发生中心（GH）增生明显减少（P＜0．05）,淋巴结转移增加,而纤维增生和单个核细胞浸润无明显变化（P＞0．05）。PCNA和C-erbB-2阳性强度在机体免疫反应指标中无明显变化（P＞0．05）。（3）淋巴结生发中心（GH）增生比副皮质区（PH)增生明显,且GH增生者淋巴结转移明显减少（P＜0．05）。结论：（1）PCNA、p53和C－erbB-2联检可作为筛选大肠癌的参考指标。 （2）机体免疫反应指标（尤其是GH增生）和P53的检测可作为判断大肠癌转移和预后的参考指标。     

自噬相关基因Beclin-1与抑癌基因PTEN、p53在大肠癌中的表达和意义

目的:检测自噬相关基因Beclin-1与抑癌基因PTEN、p53在大肠正常黏膜、大肠腺瘤、大肠癌组织中的表达,探讨它们与大肠癌发生发展的相关性。方法:采用免疫组织化学SP法检测Beclin-1与PTEN、p53在15例大肠正常黏膜、30例腺瘤及65例大肠癌组织中的表达,结合临床病理因素进行分析。结果:Beclin-1在大肠癌组阳性表达率高于正常大肠黏膜组(P<0.001)与大肠癌组织学分化程度、Dukes分期及淋巴结转移无关。PTEN在大肠正常黏膜组中的表达高于大肠癌组(P=0.001),与大肠癌组织学分化程度、Dukes分期及淋巴结转移有关。p53在大肠正常黏膜、腺瘤及大肠癌组织中的表达逐渐增高(P<0.001)与大肠癌组织学分化程度、Dukes分期及淋巴结转移有关。经Spearman秩相关检验,Beclin-1蛋白与PTEN蛋白相关系数为-0.289,呈负相关表达;Beclin-1蛋白与p53蛋白相关系数为0.347,呈正相关表达。结论:Beclin-1、PTEN、p53在大肠癌中的异常表达与大肠癌的发生、发展密切相关。自噬可能与大肠癌的发生相关,自噬活性的上调与大肠癌发生有关。自噬相关基因Beclin-1与抑癌基因PTEN、p53在大肠癌的发生发展中起协调作用。同时检测对判断大肠癌的进展程度具有重要的意义。     

c—met蛋白在大肠癌组织的表达及其与肿瘤肝转移的关系

目的：探讨c—met蛋白在癌旁正常大肠黏膜，大肠腺瘤，大肠癌组织中的表达及其与大肠癌发生、发展、肝转移的关系。方法：免疫组化法检测癌旁正常大肠黏膜，大肠腺瘤，大肠癌组织与肝转移灶组织中c—met蛋白表达水平，分析其与大肠癌病理分化程度，淋巴结转移及肝转移的关系，并比较同期切除的肝转移灶与原发灶表达水平的差异。结果：c—met蛋白在正常大肠黏膜，大肠腺瘤中表达明显低于大肠癌；有淋巴结转移的大肠癌组织中，c—met蛋白表达明显高于无淋巴结转移者；有肝转移的大肠癌组织中c—met蛋白明显高于无肝转移者。结论：c—met在大肠癌发生、发展、转移中起重要作用；c—met蛋白对大肠癌肝转移有一定的预测作用。     

c-met蛋白在大肠癌组织的表达及其与肿瘤肝转移的关系

目的：探讨c—met蛋白在癌旁正常大肠黏膜，大肠腺瘤，大肠癌组织中的表达及其与大肠癌发生、发展、肝转移的关系。方法：免疫组化法检测癌旁正常大肠黏膜，大肠腺瘤，大肠癌组织与肝转移灶组织中c—met蛋白表达水平，分析其与大肠癌病理分化程度，淋巴结转移及肝转移的关系，并比较同期切除的肝转移灶与原发灶表达水平的差异。结果：c—met蛋白在正常大肠黏膜，大肠腺瘤中表达明显低于大肠癌；有淋巴结转移的大肠癌组织中，c—met蛋白表达明显高于无淋巴结转移者；有肝转移的大肠癌组织中c—met蛋白明显高于无肝转移者。结论：c—met在大肠癌发生、发展、转移中起重要作用；c—met蛋白对大肠癌肝转移有一定的预测作用。     

Rb,p21,MMP—2和LN—R在食管鳞癌中的表达及其与侵袭和转移的关系

目的：探讨Rb,p21,MMP-2和LN－R在食管鳞癌中的表达及其与侵袭和转移的关系。方法：应用免疫组化S－P法检测Rb,p21,MMP-2和LN－R在食管鳞癌、癌旁、肌层浸润灶和淋巴结转移组织中的表达。结果：p21,MMP-2和LN－R在癌组织中的表达高于癌旁组织,分化Ⅲ级的高于Ⅰ、Ⅱ级,有淋巴结转移组高于无淋巴结转移组,具有非常显著性差异（P＜0．01）。而p21,MMP-2的表达与肿瘤的浸润有明显相关性（P＜0．05）。Rb的表达与肿瘤的浸润深度、分化程度和淋巴结转移呈负相关（分别为P＜0．05、P＜0．01和P＜0．05）。结论：抑癌基因Rb的失表达和Rb,p21,MMP-2和LN－R蛋白的过表达与食管鳞的分化程度,浸润和转移关系密切。检测Rb,p21,MMP-2和LN－R有助于对食管鳞癌的生物学行为及预后的评价。     

抑癌基因PTEN在大肠癌癌变过程中表达的实验研究

目的探讨抑癌基因PTEN的表达与大肠癌发生及浸润转移的关系。方法应用免疫组织化学EnVi-sion法原位观察正常大肠粘膜、癌旁单纯增生上皮、增生性息肉、腺瘤型息肉及癌组织中PTEN蛋白的表达。结果正常大肠粘膜均见PTEN蛋白的表达。癌旁单纯增生粘膜、增生性息肉、腺瘤型息肉及癌组织中PTEN蛋白的阳性表达率分别为92.3%、87.5%、70.6%及56.9%,其中早期癌的阳性表达率为66.7%,浸润癌的阳性表达率为55.9%。无淋巴结转移者的阳性表达率为57.5%,有淋巴结转移者为32.0%(P=0.0002)。PTEN蛋白阳性表达率随肿瘤分化程度降低而降低(P=0.028),随肿瘤Dukes分期的增加而下降,但无统计学意义(P>0.05)。结论PTEN蛋白的表达与大肠癌的发生、浸润及淋巴结转移有关,其低表达可能是大肠癌发生的一个信号。     

p53蛋白检测用于早期发现大肠癌

应用石蜡切片免疫组织化学方法，检测了p53在112例人大肠息肉中的表达，其中26例为腺癌癌变。71例腺癌中3例（4％）P53表达阳性。增生性息肉和轻度不典型增生腺瘤53表达均为阴性。p53表达随腺癌不典型增生程度的不断加重而增强。腺瘤癌变时表达率升高达88％（P＜0．001）。绒毛状腺癌的p53表达率显著增高（p＜0．05）。结果表明在大肠肿瘤形成过程中p53基因实变的作用在良性腺瘤转变为癌的阶段，可能在腺瘤恶变中起关键作用。故p53的检测时判断腺瘤的癌变倾向有重要意义，能辅助临床病理诊断，早期发现大肠癌．     

大肠肿瘤组织p53、PCNA表达及其临床意义

目的：研究p53、PCNA（增殖细胞核抗原）在大肠肿瘤组织中表达及其临床价值。方法：应用免疫组化技术（S－P法）检测17例大肠腺瘤，7例腺瘤癌变，48例大肠癌组织表达。结果：大肠腺瘤p53阳性率为29．4％，腺瘤癌变为71．4％，大肠癌p53阳性率为56．3％，PCNA强阳性（＋＋）表达与p53阳性表达呈平行关系。结论：p53、PCNA过度表达代表腺癌细胞由良性向恶性转化区域，并与大肠癌的淋巴结转移和生存期相关。     

p53蛋白在大肠癌中过度表达与组织学类型及分级的关系

目的：探讨大肠癌的发生与组织学的类型及分化程度的关系。方法：用免疫组织化学及常规病理学方法检测55例大肠癌中抑癌基因p53蛋白的过度表达。结果：p53蛋白的过度表达在大肠癌中为8％,而在正常组织及良性肿瘤中为无表达,按Turbull分期,不同分期大肠癌中p53蛋白过度表达阳性率不同,早期癌（Ⅰ－Ⅱ期）中为32．1％。（9／28）,晚期癌（Ⅲ－Ⅳ期）中为48．1％（13／27）（P＜0．015）,p53蛋白过度表达在不同组织类型中阳性率不同,如粘液腺癌为41．6％,明显低于管状腺癌的66．6％和乳头状腺癌的53．3％的阳性率。其粘液腺癌与管状腺癌的差异显（P＜0．05）,p53蛋白的过度表达在不同分化程度的大肠癌中阳性率亦不同,高分化癌为37．5％;而低分化癌为75．4％,（P＜0．05）。结论：p53蛋白过度表达可能发生于大肠癌病理过程的晚期阶段,可作为大肠癌有参考价值的预后指标之一。     

Comparative study for histology, proliferative activity, glycoproteins, and p53 protein between old and recent colorectal adenomas in Japan.

The incidence of colorectal carcinoma is increasing in Japan. Malignant transformation in colorectal neoplasia is usually considered to be owing to adenoma-carcinoma sequence. Elucidation of the recent alteration in the biological properties of colorectal adenoma is sure to be useful to understand the recent increase of the colorectal carcinoma in Japan. We compared the histopathological feature, mitotic index, proliferative activity (Ki-67 labeling index), expression of glycoproteins such as MUC2 mucin, sialyl Lewis A (SLe(a)) and sialyl dimeric Lewis X (SLe(x)), and p53 protein overexpression, between 108 adenomas in the old period (Group A, from 1969 to 1985) and 140 adenomas in the recent period (Group B, from 1995 to 1998). The histological dysplasia, mitotic index and Ki-67 labeling index of the adenomas were significantly higher in Group B than in Group A. In contrast, the expression of MUC2 mucin, which is considered to be a differentiation factor of intestinal mucosal epithelium, was significantly reduced in Group B than in Group A. The SLe(a) and SLe(x) expressions showed no significant difference between them. The p53 expression showed no significant difference between them, except for the moderate dysplasia. These findings indicate that recent colorectal adenomas show more advanced degrees of histological dysplasia, more rapid growth, and reduced differentiation than colorectal adenomas, which developed at earlier times, and may be related with the recent high incidence of colorectal carcinoma in Japan.     

Detection of genetic alterations in the p53 suppressor gene and the K-ras oncogene among different grades of dysplasia in patients with colorectal adenomas

BACKGROUND: Although it is believed that p53 suppressor gene mutations, compared with mutations in the K-ras oncogene, occur at a later stage of colorectal tumorigenesis, the distribution of these genetic alterations at an early stage remains poorly characterized. METHODS: The authors analyzed the immunoreactivity for p53 protein (p53 protein expression), which reflects the functionally altered p53 gene, and K-ras mutations at codons 12 in 68 colorectal adenomas with both low-grade and high-grade dysplasia obtained from 62 patients. RESULTS: The prevalence of p53 positive immunostaining was significantly greater compared with the prevalence of K-ras mutations both in low-grade dysplasia and in high-grade dysplasia. Twenty-two adenomas (32.3%) showed positive immunostaining for p53 protein in high-grade dysplasia and also were positive for p53 in surrounding low-grade dysplastic tissues; 20 adenomas (29.4%) showed positive immunostaining for p53 protein in high-grade dysplasia and were negative for p53 in surrounding low-grade dysplastic tissues; 8 adenomas (11.7%) showed negative immunostaining for p53 protein in high-grade dysplasia and were positive for p53 in surrounding low-grade dysplastic tissues; and 18 adenomas (26.4%) showed negative immunostaining for p53 protein in both high-grade dysplasia and in surrounding low-grade dysplastic tissues. On the whole, a significant difference (P < 0.05) was seen in the frequency of p53 positive immunostaining between low-grade dysplasia and high-grade dysplasia (44.1% and 61.8%, respectively) but not in that of K-ras mutations (20.3% and 23.4%, respectively). CONCLUSIONS: The results of this study suggest that mutation of the p53 suppressor gene occurs earlier in the adenoma-carcinoma sequence than K-ras mutation, providing a clue for further understanding of the role of the p53 gene in the early stage of colorectal tumorigenesis.     

Expression of survivin correlates with apoptosis, proliferation, and angiogenesis during human colorectal tumorigenesis

BACKGROUND: To identify the role of survivin, a novel inhibitor of apoptosis (IAP) in colorectal tumorigenesis, the authors investigated tissue expression of survivin in human colorectal tumors including 43 hyperplastic polyps, 171 adenomas with low dysplasia, 42 adenomas with high dysplasia, and 60 carcinomas in adenoma, and examined whether the expression of survivin correlated with tumor cell apoptosis, proliferation, and angiogenesis, which is known to initiate the imbalance between cell proliferation and apoptosis. METHODS: Immunohistochemical staining for the paraffin sections by using the monoclonal antibodies, survivin, p53, bcl-2, Ki-67, and CD34, was performed by the standard avidin-biotin-peroxidase technique. The apoptotic cells were detected by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling method, using an Apop Tag in situ detection kit. RESULTS: The immunoreactivity of survivin significantly increased in the transition from adenoma with low dysplasia to high dysplasia/carcinoma (P < 0.001). Similar changes in protein expression were observed for p53 but not for bcl-2, which was expressed throughout the colorectal tumorigenesis. This transition was associated with a significant decrease in the apoptotic index (AI) and significant increases in the Ki-67 labeling index (LI) and microvessel density (MVD; P < 0.001 for both). The expression of survivin inversely correlated with AI and was positively correlated with Ki-67 LI and MVD (P < 0.001 for both). CONCLUSIONS: These results suggest that, like p53, survivin plays an important role in transition from adenoma with low dysplasia to high dysplasia during human colorectal tumorigenesis.     

THE SIGNIFICANCE OF P53 GENE MUTATIONS AND EXPRESSIONS IN HUMAN COLORECTAL TUMORS

ＴＨＥＳＩＧＮＩＦＩＣＡＮＣＥＯＦＰ５３ＧＥＮＥＭＵＴＡＴＩＯＮＳＡＮＤＥＸＰＲＥＳＳＩＯＮＳＩＮＨＵＭＡＮＣＯＬＯＲＥＣＴＡＬＴＵＭＯＲＳＱｉａｎＨｕａ钱桦；ＹｕＢａｏｍｉｎｇ郁宝铭；ＺｈｏｕＸｉｇｅｎｇ周锡庚；ＷａｎｇＲｕｉｎｉａｎ王瑞年；Ｈｕａ...     

大肠癌MDR—1与p53表达关系及其意义

目的探讨大肠癌中多药耐药基因ＭＤＲ１与ｐ５３表达之间的关系。方法利用免疫组化研究６０例大肠癌及２０例大肠腺瘤ＭＤＲ－１,ｐ５３的表达。结果显示６０例大肠癌切片中ＭＤＲ－１与ｐ５３的阳性表达率为５７％和３７％,１０例正常大肠组织和２０例大肠腺瘤仅２０％显示ＭＤＲ－１阳性表达,ｐ５３在正常大肠组织,管状腺瘤中全部阴性,仅一例有不典型增生的绒毛状腺瘤为阳性表达。同时显示ｐ５３在不同分化的大肠癌中与ＭＤＲ表达呈正相关。结论１）通过检测ＤＭＲ－１可以对大肠癌病人进行化疗敏感性预测。２）ｐ５３过度表达对ＭＤＲ－１基因可能具有诱导和增加效应。３）ｐ５３和ＭＤＲ－１一起可用作判断病人预后,生物学行为的一个有用参数。     

c-met基因表达与大肠腺瘤演化与癌变过程相关性的研究

目的:评价大肠腺瘤演化与恶变过程中c-met基因的表达及其临床意义。方法:利用组织微阵列技术检测41例不同阶段的不典型增生的大肠腺瘤、16例早期癌变的大肠腺瘤和56例进展期大肠癌标本中的c-met基因。结果:在大肠腺瘤非不典型增生、轻度不典型增生、中重度不典型增生、早期癌变和进展期癌的演变中,c-met基因的阳性率分别为43.75%、50.0%、66.7%、75.0%和82.1%;过表达率分别为18.8%、10.0%、46.7%、50.0%和66.1%。而且进展期癌c-met基因的阳性率和过表达率均显著高于大肠腺瘤非不典型增生,P<0.01。大肠腺瘤演变程度与c-met阳性表达强度之间的密切关系分析显示,两者显著相关,P=0.011。结论:c-met基因表达与大肠腺瘤演化的程度及恶变相关;大肠腺瘤不典型增生级别越高,c-met基因表达越强。大肠腺瘤早期癌变时c-met基因已呈过表达状态。     

Over-expression of p53 nuclear oncoprotein in colorectal adenomas.

p53 is a nuclear phosphoprotein which controls normal cell growth. Normal p53 protein is undetectable by standard immunohistochemical staining and the over-expression found in neoplastic cells correlates with the presence of point mutations of evolutionary conserved regions of the p53 gene. We examined the expression of p53 protein in a series of 36 colorectal adenomas (13 tubular, 17 tubulovillous, 6 villous) showing different degrees of dysplasia (11 mild, 19 moderate, 6 severe), 11 moderately differentiated adenocarcinomas (6 Duke's A, 4 Duke's B, 1 Duke's C) and 5 metaplastic polyps using the polyclonal antibody CM1 which recognises p53 protein in conventionally fixed and processed histological material. We found that 15 out of 36 colorectal adenomas showed p53 immunoreactivity, although in 4 positive cases (26%) the staining was very focal (less than 0.1% positive cells). More than 80% of severely dysplastic adenomas showed strong p53 immunoreactivity and this over-expression was correlated with increased cell proliferative rate as detected by the proliferating-cell-nuclear-antigen (PCNA) staining. p53 nuclear staining was also seen in 8 out of 11 (65%) colorectal adenocarcinomas as previously shown. Our data suggest that the p53 gene mutation, with the subsequent over-expression of the protein, occurs in colorectal adenomas and may therefore be a fundamental genetic event underlying the dysplasia and loss of proliferative control that are characteristic of adenomas with malignant potential.     

Fhit, Mlh1, P53 and phenotypic expression in the early stage of colorectal neoplasms

There are two different pathways for the development of colorectal carcinoma (CRC), adenoma-carcinoma sequence (ACS) and de novo (DN) carcinogenesis. To clarify the molecular and clinicopathological characteristics in colorectal carcinogenesis, we examined endoscopically resected specimens of 30 adenomas, 30 carcinoma in adenomas (CIAs), and 18 early pure colorectal carcinomas without any adenoma component (EPCs, so called DN carcinoma) and compared the expression of Fhit, Mlh1, Msh2, P53 and cellular phenotype (HGM, MUC2 and CD10). Markedly reduced or absent Fhit expression was noted in 8 (44%) of 18 EPCs, but none of the adenomas or CIAs (p<0.0001). Six (33%) of 18 EPCs showed loss of Mlh1 expression, but rarely in adenomas and CIAs (p=0.008). This altered Fhit expression was significantly higher in submucosal invasive cancers (p=0.001), lymphatic or venous invasive cancers (p=0.0018), and tumors with altered expression of Mlh1 (p=0.01). The incidence of P53 overexpression was significantly higher in EPCs (39%) and CIAs (27%) than in adenomas (3.3%) (p<0.05). There were significant differences in phenotypic expression between the adenomatous and carcinomatous areas. Moreover, in CIAs and EPCs, the rate of P53 overexpression was significantly higher in the CD10-positive cases (53%) than CD10-negative cases (19%) (p=0.04). The present findings suggested that aberrant Fhit and Mlh1 expression could be related to DN carcinogenesis and that P53 overexpression and changes in phenotypic expression could contribute to the malignant transformation of colorectal precursor lesions.     

散发性结直肠癌、腺瘤组织中hMLH1和突变型p53表达

[目的]探讨hMLH1和p53基因在散发性结直肠癌发生机制中所起的作用。[方法]采用PV-6000二步法免疫组化检测技术对60例散发性结直肠癌，45例大肠腺瘤和26例正常大肠黏膜石蜡切片进行hMLH1和p53表达的检测。[结果]（1）60例散发性结直肠癌hMLH1蛋白阴性表达和p53蛋白阳性表达分别为11例（18．3％）和32例（53.3％），hMLH1蛋白阴性表达和p53蛋白阳性表达与患者年龄、肿瘤部位、组织学类型和分化程度密切相关（P〈0．05或P〈0．01），而与患者性别、肿瘤大体类型、肿块大小、浸润深度、淋巴结及远处转移与否和患者的Duke’s分期均无显著相关性（P〉0．05）。（2）大肠腺瘤患者p53蛋白阳性表达与患者腺瘤部位、组织学类型和不典型增生程度密切相关（P〈0．05），而与患者性别、年龄无显著相关性（P〉0．05）。（3）散发性结直肠癌中hMLH1蛋白阴性表达组p53蛋白阳性表达率（18.2％，2/11）低于阳性表达组（61．2％，30／49）（P〈O．05）。[结论]（1）大部分散发性结直肠癌是沿染色体不稳定途径发生，其中抑癌基因p53的突变起重要作用。同时，一定比例的散发性结直肠癌中存在错配修复基因的缺陷，并具有相对特殊的临床病理特征。（2）大肠腺瘤组织中有一定比例的hMLH1蛋白阴性表达和p53蛋白阳性表达，提示hMLH1和p53基因的突变可能是散发性结直肠癌发生的早期事件之一。