Analysis of the c-myc, K-ras and p53 genes in methylcholanthrene-induced mouse sarcomas.

We have examined 63 methylcholanthrene (MCA)-induced mouse sarcomas for possible correlations of mutations involving the c-myc, ras and p53 genes. The c-myc gene was found to be amplified in 18 of these sarcomas (29%). Polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) analysis and subsequent direct sequencing identified 18 cases carrying K-ras mutation at codons 12, 13 and 61 (29%). No mutation was detected in the H-ras and N-ras genes. Mutations of the p53 gene in exons 5 to 8 were found in 45 cases (71%). Comparison of these mutations revealed that out of 18 cases with c-myc gene amplifications, 10 carried K-ras mutations (56%) and 14 carried p53 mutations (78%). In contrast, among 45 cases of sarcomas without c-myc gene amplification, 8 were found to have K-ras mutations (18%). The same 45 cases were found to have 31 p53 mutations (69%). The present study suggests a strong correlation between c-myc gene amplification and K-ras gene mutation (P < 0.01). p53 gene mutation was frequently found among MCA-induced mouse sarcomas, indicating the importance of this mutation in the etiology of these tumors. However, p53 mutations were present in sarcomas regardless of the state of c-myc amplification and K-ras mutation. Therefore, a defect in the p53 gene is independent of amplification of the c-myc gene or point mutation of the K-ras gene.     

p53 Mutations, c-myc and bcl-2 Rearrangements in Human Non-Hodgkin's Lymphoma Cell Lines

Fourteen Non-Hodgkin's lymphoma cell lines were generated and assessed for the presence of structural pS3, c-myc and bcl-2 gene changes. Single or multiple changes were observed in II of the lines. Alterations of the p53 gene were most frequent and documented for 10 lines by immunoprecipition using the antibodies PAb 240 and PAb 1801. sequencing studies and Southern blot analysis. A detailed study was performed in one of the cell lines (XI-Ly 4) for which material of the original tumor sample was, available. Two point mutations identified by sequencing cDNA derived from the cell line were also present in the original tumor specimen. In contrast. DNA prepared from fibroblasts of the same patient did not show the mutations. Six of the 14 lines demonstrated c-myc rearrangements, while bcl-2 changes were observed in 4. The presence of c-myc was associated with shorter survival of this group of patients with aggressive disease. None of the other changes present as single or composite alterations were correlated with clinical outcome measures.     

Cyclin D1、p53及c-myc基因表达与胃癌生物学行为的关系

目的 :探讨cyclinD1、p53及c myc基因表达与胃癌生物学行为的关系。方法 :采用S P免疫组织化学方法研究了c myc、p53及cyclinD1基因在 63例胃癌中的表达。结果 :63例胃癌中cyclinD1、P53及c myc蛋白染色阳性率分别为 32 .75 %、2 5 .40 %及 52 .38% ;最大径≥ 4cm胃癌cyclinD1、P53及c myc蛋白染色阳性率明显高于 <4cm的胃癌 (P <0 .0 5) ;≤ 49年龄组胃癌cyclinD1蛋白染色阳性率 (52 .94% )明显高于≥ 50岁年龄组 (2 3 91 % ) ;早期胃癌、侵及肌层胃癌及侵及浆膜层胃癌c myc蛋白染色阳性率分别为 35 .2 9%、44 .44%及 67.86 % ,浆膜层胃癌阳性率显著高于粘膜下层以内胃癌和肌层胃癌 (P <0 .0 5) ;高分化腺癌、低分化腺癌及粘液癌c myc蛋白染色阳性率分别为 74.0 7%、2 8.0 0 %及 54 .55 % ,三组间有显著性差异 (P <0 .0 5) ;cyclinD1、p53及c myc同时阳性者 8例 ,均为进展期胃癌 ,cyclinD1与P53、P53与c myc蛋白染色密切相关 ;cyclinD1、P53蛋白染色和胃癌的大体分型、分化程度和组织类型无明显关系 (P >0 .0 5)。结论 :cyclinD1、p53及c myc基因过表达 ,可能促使胃癌细胞增殖 ,使胃癌细胞具有更强的侵袭力     

p53与c-myc和cyclin B1在卵巢上皮性癌组织中的表达及意义

目的：研究 p53、c-myc和cyclin B1在卵巢良性肿瘤及上皮性卵巢癌组织中表达的相关性及临床意义.探讨p53、c-myc和cyclin B1在上皮性卵巢癌组织发生、发展中的作用.方法：应用免疫组化SP法检测61例上皮性卵巢癌、29例卵巢良性上皮性肿瘤和12例正常卵巢组织的p53、 c-myc和cyclin B1基因蛋白表达情况,并分析它们之间的关系.结果：上皮性卵巢癌中p53、c-myc和cyclin B1表达率分别为50.82%（31/61）、60.66%（37/61）和49.18%（30/61）; 在良性卵巢上皮性肿瘤中p53、c-myc和cyclin B1的蛋白表达率分别为10.34%（3/29）、17.24%（5/29）和13.79%（4/29）.p53、c-myc和cyclin B1在Ⅰ、Ⅱ期与Ⅲ、Ⅳ期上皮性卵巢癌组织中的阳性表达,差异均有统计学意义,P=0.032 81.p53、c-myc和cyclin B1在上皮性卵巢癌G1与G2、G3的阳性表达,差异有统计学意义,P=0.041 08.在正常卵巢组织中均未见p53、c-myc和cyclin B1蛋白的表达.结论：p53、c-myc和cyclin B1作为细胞周期调节因子参与上皮性卵巢癌的发生、发展,其协同作用促进上皮性卵巢癌的发生、发展并可能与预后有关.     

二氢嘧啶脱氢酶、胸苷酸合成酶、c-myc和p53基因在小鼠肝组织中表达的昼夜节律性研究

背景与目的：5-Fluorouracil(5-FU)主要通过抑制胸苷酸合成酶发挥抗癌作用,而二氢嘧啶脱氢酶是5-FU体内代谢的一个起始酶和限速酶。在本研究中,我们对二氢嘧啶脱氢酶、胸苷酸合成酶、c-myc和p53基因在小鼠肝脏中表达的昼夜节律进行研究。方法：本实验共采用了24只雄性B6D2F1小鼠。所有实验动物在实验中进行了4周光照同步化(12h光照：12h黑暗)。体温和休息-活动节律通过腹腔埋置的微型感受器进行动态监测。动物分别在3,7,11,15,19,23HALO(灯亮后小时数)被处死并取出肝脏冻存。肝脏标本中抽提的总RNA用LightCycler-SYBR Green I^TM扩增系统进行实时定量RT-PCR。结果：小鼠的体温和休息-活动均呈现明显和相似的昼夜节律,其峰值均位于黑暗期(相当于小鼠活动相),谷值则位于光照期(相当于小鼠休息相)。二氢嘧啶脱氢酶在mRNA水平呈现出明显的昼夜节律性,其峰值时间位于16HALo左右即位于小鼠活动相(P=0．0012)。胸苷酸合成酶在mRNA水平具有昼夜节律表达的趋势,其峰值时问出现在光照期(P=0．079)。C-myc和p53在mRNA水平的节律性表达在本实验中无统计学意义。结论：二氢嘧啶脱氢酶和胸苷酸合成酶在mRNA水平呈现出昼夜节律性,二者峰值时间相差约12h,这一结果提示可以利用二者在转录水平的时间差异用5-Fu进行时间化疗。     

Loss of a highly conserved domain on p53 as a result of gene deletion during Friend virus-induced erythroleukemia

We have investigated a mutation in the p53 gene leading to expression of a truncated 46,000-dalton protein in a Friend virus-induced erythroleukemia cell line. cDNA sequence analysis revealed a deletion of nucleotide sequences in exon 7 and part of exon 8; 17 additional nucleotides, derived from intron 6, were present in the cDNA and served to maintain the reading frame of the encoded protein. Comparison with p53 protein from other species indicated that the region of the molecule missing in p46 included a highly conserved region. In addition, p46 failed to bind SV40 large T antigen in vitro under conditions which promoted binding of p53 to large T. It seems likely, therefore, that an important functional property of p53 may be affected by the mutation.     

Status of c-myc, p53 and retinoblastoma genes in human papillomavirus positive and negative squamous cell carcinomas of the anus.

We have examined a series of squamous cell carcinomas (SCC) of the anus, anal intraepithelial neoplasia grade III (AINII) lesions and haemorrhoids for the presence of sequences from transforming human papillomavirus (HPV) types by polymerase chain reaction (PCR)/Southern blotting. In addition, the same DNAs have been analysed for abnormalities in the c-myc, p53 and retinoblastoma (Rb-1) gene loci by Southern blotting. HPV16 sequences were detected in a total of 38 of 50 (76%) and HPV18 sequences in 4 of the 50 cancers (8%). Of 12 haemorrhoids examined, none contained HPV16 or HPV18 sequences. Amplification of c-myc was demonstrated in 15 of the 50 cancers (30%), of which 13 were HPV16 positive, and one also positive for HPV18. Amplification of c-myc was not observed in the 5 AINIII or any of the 41 haemorrhoid DNAs analysed. Rearrangement of c-myc was not seen in any of the DNAs. Gross rearrangement, or loss of p53 or Rb-1 loci was not observed in any normal or tumor tissue. However, in preliminary analysis of p53 sequence, three tumours negative for HPV were heterozygous for p53 point mutation whereas six HPV positive tumours and two haemorrhoids were wild-type sequence throughout exons four to ten.     

脂肪肉瘤c-myc和p53基因蛋白的表达及意义

背景与目的：原癌基因c-myc和抑癌基因p53与脂肪肉瘤的关系的研究较少,脂肪肉瘤中是否存在p53基因突变文献报道不一,本文拟探讨脂肪肉瘤中c-myc、p53基因蛋白表达的水平及意义,以期为本组肿瘤发生发展及病理诊断、鉴别诊断提供一定的分子生物学资料。方法：采用链菌素抗生物素－生物素（labelled streptavidin-biotin,LSAB)免疫组化法、聚合酶链反应－单链构象多态性分析（Single strand conformation polymorphism analysis of polymerase chain reaction products,PCR-SSCP)及DNA序列分析方法。结果：c-myc和p53蛋白在脂肪肉瘤表达阳性率分别为38．09％（16／42）和48．08％（25／52）。不同类型脂肪肉瘤,分化良好者阳性率均明显低于分化较差者。脂肪肉瘤中c-myc和p53蛋白表达呈正相关。c-myc和p53蛋白表达在原发者和复发者之间的差异均无统计学意义。p53第6、7、8外显子PCR－SSCP分析,2例多形性脂肪肉瘤出现异常泳动带。DNA序列分析证实1例第8外显子第268位编码区出现错义突变（AAC→ATC）,另1例第6例显子第221位编码区出现可疑杂合性同义突变（GAG→GAA)。结论：c-myc和p53蛋白与脂肪肉瘤的形成及分化和恶性程度有关。它们可作为判断脂肪肉瘤分化程度及恶性程度参考指标之一,但与肿瘤复发无关。在脂肪肉瘤发生发展中两者可能起协同作用。脂肪肉瘤中p53基因第6、8外显子分别存在点突变。     

Analysis of the c-myc, K-ras and p53 Genes in Methylcholanthrene induced Mouse Sarcomas

We have examined 63 methylcholanthrene (MCA)-induced mouse sarcomas for possible correlations of mutations involving the c-myc, ras and p53 genes. The c-myc gene was found to be amplified in 18 of these sarcomas (29%). Polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) analysis and subsequent direct sequencing identified 18 cases carrying K-ras mutation at codons 12, 13 and 61 (29%). No mutation was detected in the H-ras and N-ras genes. Mutations of the p53 gene in exons 5 to 8 were found in 45 cases (71%). Comparison of these mutations revealed that out of 18 cases with c-myc gene amplifications, 10 carried K- ras mutations (56%) and 14 carried p53 mutations (78%). In contrast, among 45 cases of sarcomas without c-myc gene amplification, 8 were found to have K- ras mutations (18%). The same 45 cases were found to have 31 p53 mutations (69%). The present study suggests a strong correlation between c-myc gene amplification and K- ras gene mutation ( P < 0.01). p53 gene mutation was frequently found among MCA-induced mouse sarcomas, indicating the importance of this mutation in the etiology of these tumors. However, p53 mutations were present in sarcomas regardless of the state of c-myc amplification and K- ras mutation. Therefore, a defect in the p53 gene is independent of amplification of the c-myc gene or point mutation of the K- ras gene.     

黑色素瘤抗原基因MAGE-1、MAGE-3和抑癌基因p53在肺癌中表达的研究

目的:分析肺癌组织MAGE-1和MAGE-3基因以及p53基因表达及其相互关系。方法:取肺癌组织标本30例,另取癌周组织作为对照。采用逆转录聚合酶链反应(RT-PCR)方法,检测MAGE-1和MAGE-3基因以及p53基因的表达。结果:MAGE-1,MAGE-3在肺癌中有较高表达,MAGE-3的表达高于MAGE-1的表达。p53在肺癌中表达较低,在正常组织中表达较高;MAGE-1在肺腺癌中表达较鳞癌高,MAGE-3在肺鳞癌中表达较高;MAGE-1,MAGE-3的表达可能与肿瘤分化程度无关;p53在小细胞肺癌中的表达有待进一步研究;p53与MAGE在体内表达成负相关。结论:MAGE-1、MAGE-3和p53在肺癌组织与正常组织中有不同的表达,MAGE-1、MAGE-3的表达与病理类型有关,与肿瘤分化无关。     

大肠肿瘤p53蛋白过表达对原位Th1／Th2平衡的影响

目的：评价p53蛋白过表面对大肠腺瘤和大肠癌局部辅助T细胞（Th1/Th2)平均的影响,进而探讨大肠癌发生的免疫学机制,方法：研究对象包括大肠腺瘤30例,大肠癌38例,癌旁正常粘膜68例作为对照组。石蜡切片以免疫组化法检测p53蛋白表达,采用酶联免疫吸附试验（ELISA）检测肠组织培养上清液中4种细胞因子（IL－2,IL－4,IL－10,IFN－r)水平。结果：p53蛋白表达阳性组培养上清液的IL－2,IFN－r水平显著低于阴性组和对照组（P＜0．01）,而IL－10则高于阴性组及对照组（P＜0．05）,各组IL－4水平未显示差异（P＞0．05）,结论：p53蛋白表达引起原位Th1/Th2平衡失调,表现为由Th1向Th2漂移,初步推断：p53基因失活在大肠癌发生的免疫学机制中可能具有重要作用。     

Ki-67、c-myc、p53在食管癌中的表达及其意义

目的 探讨Ki-67、c-myc、p53在食管癌中的表达及其意义.方法 选取食管癌标本25例、切缘远端正常组织标本25例,采用免疫组织化学法检测组织中Ki-67、c-myc、p53蛋白的表达情况.结果 食管癌组织中Ki-67、c-myc、p53中位表达量分别为5.0、2.0、3.0,明显高于癌旁正常组织的1.0、0.5、0.3（均P＜0.05）.高分化食管癌组织Ki-67中位表达量（3.0）低于中低分化组（6.0）,差异有统计学意义（P＜0.05）.食管癌组织Ki-67与c-myc的表达呈正相关（P＜0.05）.结论 食管癌组织中Ki-67、c-myc、p53高表达,且随分化程度升高而升高,Ki-67、c-myc、p53有望成为食管癌的肿瘤标志物.     

EG-1、Her-2、p53、c-myc、bcl-2在乳腺癌中表达的研究进展

新近发现的基因EG-1在乳腺癌中有高表达,其与内皮细胞及上皮细胞的增生激活状态相关.Her-2、p53、c-myc、bcl-2在乳腺癌中的研究较多,其在细胞信号转导通路中的作用已有一定认识.全文就5个基因的研究概况作一综述.     

bcl-2、p53、c-myc 蛋白在胃癌中表达的研究

 目的　研究胃癌组织中 bcl- 2、p5 3、c- myc表达与其临床病理的相关性。方法　对有随访的不同分化的胃癌 5 0例、癌旁不典型增生粘膜病变 47例 ,及 2 0例正常胃粘膜进行免疫组化ABC法标记。结果　 bcl- 2蛋白在癌旁轻、中、重度不典型增生的阳性率分别为 5 %、1 7.6 %、2 0 .0 % ,它们间无显著差异 P>0 .0 5 % ) ,在高分化胃癌中阳性率为 80 .0 %。与低分化的 5 0 .0 %相比 ,有显著差异 (P<0 .0 5 )。p5 3在高分化胃癌中阳性率为 5 0 .0 %。明显低于低分化的 84.6 % (P<0 .0 5 )。结论　bcl- 2和 p5 3可作为肿瘤分化和估计预后的主要参考指标之一。     

CyclinD1 c-myc和p53的表达与肝细胞癌生物学行为关系

目的:探讨肝细胞癌(Hepatocellularcarcinoma,HCC)及癌旁肝组织CyclinD1、c-myc及p53蛋白表达的意义及其与肝癌生物学行为关系。方法:采用EnVisionTMplus免疫组织化学方法检测CyclinD1、c-myc及p53蛋白在52例HCC及癌旁肝组织中的表达。结果:CyclinD1及c-myc在HCC组织中的阳性率明显高于在癌旁肝组织中的阳性率(P<0.05),在HCC中p53的阳性表达与CyclinD1、c-myc的阳性表达呈正相关(r=0.4637,P=0.0022、r=0.3445,P=0.0273,);CyclinD1、c-myc及p53在人肝癌组织中的检出率与肝外转移、术后复发及肿瘤分化程度明显有关(P<0.05),CyclinD1的检出率与门静脉癌栓明显有关(P<0.05),p53的检出率与血清AFP和TSGF水平有显著性差异(P<0.05);CyclinD1、c-myc及p53的检出率与临床分期、肿瘤大小、肿瘤个数、HBsAg状况无明显关系。结论:CyclinD1、c-myc及p53蛋白的过表达可促使肝癌细胞增殖,使肝癌细胞具有更强的侵袭力,与肝癌的发生、发展密切相关。     

Long term follow-up of c-myc, p53 and proliferation measurements in malignant melanoma.

AIMS: We report a prospective study examining the prognostic significance of the c-myc oncoprotein, p53 tumour suppressor gene and proliferation rate measurements in malignant melanoma. METHODS: Flow cytometry (FCM) was used to measure the expression of c-myc, p53 and proliferation parameters in patients who had received an injection of the thymidine analogue bromodeoxyuridine prior to surgery. RESULTS: Sixty-seven patients had successful FCM measurements of the three parameters. c-myc was detected in 97% of patients with a median cell positivity of 62%. The median p53 positivity was 13%. The median potential doubling time (T(pot)) of the tumours wasf 9.4 days. In univariate analysis, each of the parameters showed an association with survival in metatstatic disease with rapid proliferation (p=0.006) or overexpression of c-myc (p=0.038) related to poor survival whereas increased positivity for p53 predicted better survival (p=0.013). CONCLUSIONS: These data indicate that laser cytometric technology can be used to obtain quantitative data on oncoproteins expression and cell proliferation rates in clinical samples of malignant melanoma.