胃癌癌旁组织中p53、p16和bcl-2蛋白表达及其关系的探讨

目的：研究胃癌癌旁组织中抑癌基因和抗凋亡基因蛋白的表达及其内在关系。方法：胃镜及外科手术中取４０例 胃癌患者的癌组织和癌旁组织各两块,石蜡包埋,切片ＨＥ染色作病理及免疫组织化学检查ｐ５３、ｐ１６和ｂｃｌ－２基因蛋 白表达。结果：ｐ５３在胃癌组织中阳性表达率４２．５％,癌旁组织１２．５％,有显著性差异（Ｐ＜０．０１）,其表达强度也有显著 性差异（Ｐ＜０．０１）;ｐ１６在癌旁组织阳性表达率为６０％,显著高于胃癌组织３７．５％（Ｐ＜０．０５）,其表达强度也有显著性差 异（Ｐ＜０．０５）;ｂｃｌ－２在胃癌组织和癌旁组织阳性表达率无显著性差异（６７．５％比４７．５％,Ｐ＞０．０５）,其表达强度也无显 著性差异（ｐ＞０．０５）。ｐ５３与ｐ１６、ｐ１６与ｂｃｌ－２表达之间均无显著相关性（Ｐ＞０．０５）,而ｐ５３与ｂｃｌ－２表达之间存在显著相 关性（Ｐ＜０．０５）。结论：在胃癌发生发展过程中,抑癌基因（ｐ５３、ｐ１６）４抗凋亡基因（ｂｃｌ－２）之间存在既独立又协同的作 用。     

胃癌组织中生长抑素Ⅱ型受体基因低表达与淋巴结转移

目的　恶性肿瘤的发生和转移机制尚未完全明确，我们旨在研究胃癌癌灶（Ｃ） 、癌旁组织（Ｐ） 和远处正常组织（ Ｎ） 生长抑素（ＳＳ） 含量及其Ⅱ型受体（ＳＳＲ Ⅱ） 基因的表达情况，及其与腹腔淋巴结转移的关系，探讨ＳＳ 及ＳＳＲⅡ在胃癌发生、发展和转移中的作用．方法　外科手术切除的胃癌标本３６ 例，分为２ 组：腹腔淋巴结转移组（Ａ 组）２０ 例，男１７ 例，女３ 例，年龄５８－４ 岁±１４－８ 岁；Ｂ 组（ 无淋巴结转移）１６ 例，男１４ 例，女２ 例，年龄６０－５ 岁±１４－２ 岁． 大体标本离体后立即取癌灶、癌旁和远处正常组织，应用ＲＩＡ 法检测其ＳＳ 含量、同位素掺入ＲＴＰＣＲ 法检测ＳＳＲⅡ基因表达情况（ 以ｃｐ ｍ 高低间接反映基因的表达强弱） ．结果　Ａ，Ｂ 两组的年龄和性别分布无显著性差异（ Ｐ＞ ０－０５） ．癌灶ＳＳ 含量明显低于癌旁和正常粘膜（ Ｐ＜ ０－０５） ，但Ａ，Ｂ 两组间的差异无统计学差异（ｐ ｍｏｌ／ ｇ ，Ａ 组：Ｃ １５ ±８ ，Ｐ３０ ±８ ， Ｎ３２ ±１１ ；Ｂ 组：Ｃ １６ ±９ ， Ｐ３２ ±１０ ， Ｎ ３６ ±１２） ．Ａ 组癌灶ＳＳＲⅡ基因表达明显低于癌旁和远处粘膜（ Ｐ＜ ０－０１） ，也低于Ｂ 组癌灶的ＳＳＲⅡ的表达（     

胃癌、癌旁组织中抑癌基因和凋亡调节基因表达及其内在关系

目的 研究胃癌、癌旁组织中抑癌基因ｐ５３、ｐ１６和关键性凋亡调节基因ｂｃｌ－２蛋白的表达及其内在的关系,进一步探讨胃癌发病可能的分子机制。方法 术中取３０例胃癌患者的癌组织,癌旁组织各２块,石蜡包埋,切片分别作ＨＥ染色病理检查及免疫组织化学检查ｐ５３、ｐ１６、ｂｃｌ－２基因蛋白表达。结果 ｐ５３、ｐ１６和ｂｃｌ－２表达与胃癌分期、分化程度及有无淋巴结转移均无显著关系（Ｐ〉０．０５）,但ｂｃｌ－２与     

胃癌癌旁组织中幽门螺杆菌感染及基因改变

应用ＰＣＲ、ＰＣＲ／ＲＦＬＰ对胃癌及癌旁组织中Ｈｐ感染进行了检测，并应用ＰＣＲ／ＲＦＬＰ、ＰＣＲ／ＳＳＣＰ、ＰＣＲ－ＤＮＡ测序探讨了Ｈｐ感染与ｒａｓ基因、ｐ５３基因变化的关系。研究结果发现：２４例胃癌组织Ｈｐ阳性１２例（１２／２４，５０％），２４例癌旁组织Ｈｐ阳性１１例（１１／２４，４８．５％），两者无显著差异，胃癌组基因改变者１７例（１７／２４，７０．８３％），其中Ｈｐ阳性１２例（１２／１７，７０．５９％），７例无基因改变者未发现Ｈｐ感染。癌旁组基因改变者１例，其中Ｈｐ为阴性。２４对胃癌ｐ５３Ｅｘｏｎ４的杂合缺失率为４７．３７％（９／１９）。ｐ５３Ｅｘｏｎ５、６、７、８突变在癌组织中有１１例（１１／２４；４５．８％），癌旁组仅一例，发生Ｈ－ｒａｓ１２位点突变者７例（７／２４，２９．１７％），癌旁组则无突变。胃癌基因改变与Ｈｐ＋相关性比较发现，Ｈｐ感染与基因改变关系密切（Ｐ＜０．０１）。各种基因改变中以ｐ５３改变似与Ｈｐ感染关系更紧密（ｒ＝０．５Ｐ＜０．０５）。结果表明，ｒａｓ基因及ｐ５３基因的协同作用在胃癌的致病机理中显示出重要作用。在癌变过程中，可能Ｈｐ的感染是基因改变进而促进组织恶变的促动因素之一。     

人胃癌p16/CDKN2基因蛋白质水平的异常表达

目的ｐ１６／ＣＤＫＮ２基因是新近发现的肿瘤抑制基因，已有研究表明该基因在许多肿瘤出现缺失、突变或重排．胃癌细胞系中有高频率纯合子缺失，应用Ｓｏｕｔｈｅｒｎｂｌｏｔ和ＳＳＣＰ技术在胃癌手术标本中未发现有该基因的缺失．本文首次研究胃癌中ｐ１６／ＣＤＫＮ２基因在蛋白水平的表达．方法应用蛋白Ａ金探针免疫组化技术对３０例胃癌和２０例正常胃粘膜标本的ｐ１６进行分析．结果所有正常对照组均有ｐ１６表达，其阳性细胞百分率为７２５５％±１７２２％；而胃癌中的阳性细胞百分率为５４９０％±２８９０％，明显低于正常对照（Ｐ＜００５）．在肿瘤病例中有２３３３％（７／３０）ｐ１６表达减低，１０％（３／３０）未表达ｐ１６．此外有１例呈过度表达．结论胃癌中有ｐ１６的异常表达，免疫组化技术可能较准确地反映ｐ１６的表达，更适合于临床研究．     

Apollon蛋白在胃癌组织中的表达及意义

目的 研究Apollon基因在胃癌组织的表达及意义.方法 采用免疫组化SP法对42例胃癌组织、15例癌旁组织、10例正常胃组织中Apollon基因表达蛋白进行检测.结果 10例正常成人胃组织中Apollon基因均无表达,胃癌及癌旁正常组织Apollon基因表达阳性率分别均为80.9%和20.0%,胃癌组织明显高于正常及癌旁组织(P<0.05);Apollon基因表达与患者的年龄、性别无关(P>0.05),而与肿瘤的分级、分期有关(P>0.05).结论 Apollon基因表达升高与胃癌密切相关,可能参与胃癌的发生.     

肿瘤抑制基因P53、P16在胃上皮癌变中的表达

采用免疫组化ＡＢＣ法检测肿瘤抑制基因Ｐ５３、Ｐ１６蛋白在各级胃粘膜病变中的表达变化，以加深对胃癌发生分子学基础的认识。结果：萎缩性胃炎即有Ｐ５３蛋白阳性反应，且随着病变的加重表达率升高；Ｐ１６蛋白在正常胃粘膜中表达率最高，随着病变发展，其免疫阳性率呈下降趋势；此外两者在癌组织中的表达呈显著性相关（Ｐ＜０．０１），全部５０例癌组织中，检出Ｐ５３阳性表达组织２６例，其中同时伴有Ｐ１６阳性反应的组织１７例（１７／２６），伴Ｐ１６表达缺失的组织９例（９／２６），前者高于后者（Ｐ＜０．０５）。结果提示：肿瘤抑制基因Ｐ５３、Ｐ１６的异常表达发生于胃粘膜癌变早期，胃癌组织中Ｐ５３基因异常可能对Ｐ１６蛋白表达有反馈调节作用     

食管癌p16基因缺失分析

目的观察抑癌基因ｐ１６在不同病程食管癌患者癌组织中的缺失情况．方法采用ＰＣＲ方法检测２６例食管癌患者癌组织标本及邻近正常食管上皮组织标本ｐ１６基因的缺失情况．结果在２６例食管癌组织中检出１４例标本有ｐ１６基因第２外显子缺失，缺失率５３８％，而癌旁正常食管组织均无缺失．在Ⅱ期至Ⅳ期食管癌（Ｔ２Ｎ０Ｍ０至Ｔ４Ｎ１Ｍ１）均检测到ｐ１６基因缺失．结论ｐ１６基因缺失可能在食管癌发生及发展中起较重要作用     

胃癌HOXB6基因异常甲基化及其表达

目的 检测胃癌组织中HOXB6基因是否存在异常甲基化，并探讨其与基因表达及临床因素的关系。方法 用联合重硫酸盐限制性分析法（COBRA法）对7种胃癌细胞系和73例胃癌中层得的胃镜下活检组织进行HOXB6基因的甲基化定量检测，并采用逆转录聚合酶链反应方法检测基因的表达及脱甲基化处理后基因的再表达，结果 7种胃癌细胞系中有4种异常甲基化，异常甲基化的细胞系基因表达减少或消失，并且脱甲基化处理后基因可以重新表达，73例胃癌患者的癌部位和非癌部位的活检组织中，20例癌组织甲基化阳性（27.40%)，而非癌组织中无1例阳性。结论 胃癌中HOXB6基因的异常甲基化与基因表达抑制密切相关。并且脱甲基化后基因可以再表达；胃癌组织中HOXB6基因异常甲基化具有高度特异性，可作为肿瘤标志物用于临床诊断。     

肿瘤抑制基因p53及p16与胃癌生物学行为的关系

目的探讨肿瘤抑制基因ｐ５３和ｐ１６异常与胃癌生物学行为的关系．方法采用免疫组化ＡＢＣ法检测５８例原发性胃癌（男３８例，女２０例，年龄３７岁～７６岁），Ｐ５３和Ｐ１６蛋白的表达变化．所有组织均新鲜取材，并迅速用８５０ｍｌ／Ｌ酒精固定，石蜡包埋，连续切片．结果受检组织中ｐ５３和ｐ１６阳性表达率分别为５１７％（３０／５８）和４８３％（２８／５８）．Ｐ５３蛋白在低分化胃癌（７００％）、进展期胃癌（５６９％）、淋巴结阳性胃癌（７４１％）中的表达率高于相应的高分化、早期、淋巴结阴性胃癌的表达率（２７３％，１４３％，３２３％）（Ｐ＜００５），且ｐ５３高表达多见于弥散型胃癌（同肠型胃癌比）、累及浆膜的胃癌也较局限于粘膜层的胃癌有更高的Ｐ５３蛋白表达（Ｐ＜００５）；Ｐ１６蛋白表达与胃癌大多数生物学行为无明显关系，但其在淋巴结阳性胃癌中的表达率（３３３％），低于淋巴结阴性胃癌中的表达率（６１３％）；相关性分析显示；ｐ５３阳性组织大多伴有Ｐ１６蛋白阳性表达（Ｐ＜００５）．结论Ｐ５３蛋白异常表达对胃癌生物学行为有广泛影响，Ｐ１６蛋白表达缺失可能是胃癌淋巴结转移的重要促发因素．     

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.     

Expression, deletion [was deleton] and mutation of p16 gene in human gastric cancer

AIM: To investigate the relationship between the expression of p16 gene and the gastric carcinogenesis, depth of invasion and lymph node metastases, and to evaluate the deletion and mutation of exon 2 in p16 gene in gastric carcinoma. METHODS: The expression of p16 protein was examined by streptavidin-peroxidase conjugated method (S-P);the deletion and mutation of p16 gene were respectively examined by polymerase chain reaction (PCR) and polymerase chain reaction single-strand conformation polymorphism analysis (PCR-SSCP) in gastric carcinoma. RESULTS: Expression of p16 protein was detected in 96.25% (77/80) of the normal gastric mucosa, in 92.00% (45/50) of the dysplastic gastric mucosa and in 47.54% (58/122) of the gastric carcinoma. The positive rate of p16 protein expression in gastric carcinoma was significantly lower than that in normal gastric mucosa and dysplastic gastric mucosa (P < 0.05). The positive rate of p16 protein expression in mucoid carcinoma 10.00% (1/10) was significantly lower than that in poorly differentiated carcinoma 51.22% (21/41), undifferentiated carcinoma 57.69% (15/26) and signet ring cell carcinoma 62.50% (10/16) (P < 0.05). The positive rate of p16 protein in 30 cases paired primary and lymph node metastatic gastric carcinoma: There was 46.67% (14/30) in primary gastric carcinoma, 16.67% (5/30) in lymph node metastatic gastric carcinoma. The positive rate of lymph node metastatic carcinoma was significantly lower than that of primary carcinoma (P < 0.05). There was of p16 gene mutation in exon 2, but 5 cases displayed deletion of p16 gene in exon 2 in the 25 primary gastric carcinomas. CONCLUSIONS: The expression loss of p16 protein related to the gastric carcinogenesis, gastric carcinoma histopathological subtypes and lymph metastasis. The mutation of p16 gene in exon 2 may not be involved in gastric carcinogenesis. But the deletion of p16 gene in exon 2 may be involved in gastric carcinogenesis.     

Expression of p53 in early (T1) gastric carcinoma and precancerous adjacent mucosa.

Abnormalities of the tumour suppressor gene p53 have been shown in approximately 60% of advanced gastric adenocarcinomas and it has been suggested that the immunohistochemical finding of increased p53 expression is a prognostic marker in gastric cancer. No studies of early (T1) tumours have been reported. Over expression of p53 protein in 95 early gastric carcinomas and in adjacent mucosa was investigated using immunohistochemistry with antibody CM1. Thirty five per cent of the tumours were positive. The frequency of p53 positivity in tumours of tubular histological type (46%) was significantly higher than that in signet ring tumours (10%) (p = 0.006), and neoplasms that invaded deeply into the submucosa were more frequently positive (45%) than others (30%). Five of eight (62%) T1 tumours with lymph node metastases showed immunoreactive p53. In signet ring tumours, immunopositivity correlated with the frequency of DNA aneuploidy. p53 Over expression was also found in 15% of 26 examples of high grade dysplasia in mucosa adjacent to invasive tumours. No positivity was found in intestinal metaplasia or in normal mucosa. The findings show that immunocytochemically demonstrable over expression of p53 correlates with other morphological markers of aggressiveness in T1 gastric adenocarcinoma. The increasing frequency of p53 immunoreactivity in the sequence of high grade dysplasia-->early gastric cancer-->advanced gastric cancer supports the view that abnormalities of p53 are related to tumour progression in gastric carcinogenesis.     

Expression, deleton and mutation of p16 gene in human gastric cancer

AIM To investigate the relationship between the expression of p16 gene and the gastric carcinogenesis,depth of invasion and lymph node metastases, and to evaluate the deletion and mutation of exon 2 in p16 gene in gastric carcinoma. METHODS The expression of P16 protein was examined by streptavidin-peroxidase conjugated method (S-P); the deletion and mutation of p16 gene were respectively examined by polymerase chain reaction (PCR) and polymerase chain reaction single-strand conformation polymorphism analysis (PCR-SSCP) in gastric carcinoma. RESULTS Expression of P16 protein was detected in 96.25% (77/80) of the normal gastric mucosa, in 92.00% (45/50) of the dysplastic gastric mucosa and in 47.54% (58/122) of the gastric carcinoma. The positive rate of P16 protein expression in gastric carcinoma was significantly lower than that in normal gastric mucosa and dysplastic gastric mucosa (P＜0.05). The positive rate of P16 protein expression in mucoid carcinoma 10.00% (1/ 10) was significantly lower than that in poorly differentiated carcinoma 51.22% ( 21/ 41 ),undifferentiated carcinoma 57.69% (15/26) and signet ring cell carcinoma 62.50% (10/ 16) (P＜0.05). The positive rate of p16 protein in 30 cases paired primary and lymph node metastatic gastric carcinoma: There was 46.67% (14/30) in primary gastric carcinoma, 16.67% (5/30) in lymph node metastatic gastric carcinoma. The positive rate of lymph node metastatic carcinoma was significantly lower than that of primary carcinoma (P＜0.05). There was of p16 gene mutation in exon 2, but 5 cases displayed deletion of p16 gene in exon 2 in the 25 primary gastric carcinomas. CONCLUSIONS The expression loss of P16 protein related to the gastric carcinogenesis, gastric carcinoma histopathological subtypes and lymph metastasis. The mutation of p16 gene in exon 2 may not be involved in gastric carcinogenesis. But the deletion of p16 gene in exon 2 may be involved in gastric carcinogenesis.     

LINE-1 family member GCRG123 gene is up-regulated in human gastric signet-ring cell carcinoma

AIM： To analyze the expression profiles of a human gastriccancer-related gene, GCRG123, in human gastric signetring cell carcinoma tissues, and to perform bioinformatics analysis on GCRG123.
METHODS： In situ hybridization was used to explore the GCRG123 expression pattern in paraffin-embedded gastric tissues, including 15 cases of signet-ring cell carcinoma, 15 of intestinal-type adenocarcinoma, and 15 of normal gastric mucosa. Northern blotting was used to analyze the differences in GCRG123 expression between stomach signet-ring cell carcinoma and intestinal-type adenocarcinoma tissues. Online software, including BLAST, Multalin and BLAT, were applied for bioinformatics analysis. National Center for Biotechnology Information （NCBI） and the University of California Santa Cruz （UCSC） databases were used for the analyses.
RESULTS： The in situ hybridization signal appeared as blue precipitates restricted to the cytoplasm. Ten out of 15 cases of gastric signet ring cell carcinoma, normal gastric mucosal epithelium and pyloric glands showed high GCRG123 expression. Low GCRG123 expression was observed in gastric intestinal-type adenocarcinoma and normal gastric glands. Northern blotting revealed that GCRG123 was up-regulated in signet-ring cell carcinoma tissue but down-regulated in intestinal-type adenocarcinoma tissue. BLAST and Multalin analyses revealed that the GCRG123 sequence had 92% similarity with the ORF2 sequence of human long interspersed nuclear element retrotransposons （LINE-1, L1）. BLAT analysis indicated that GCRG123 mapped to all chromosomes. GCRG123 was found to integrate in the intron-17 and -23 of Rb, 5＇ flanking region of IL-2 and clotting factor Ⅸ genes.
CONCLUSION： GCRG123, an active member of the Lt family, was up-regulated in human gastric signet-ring cell carcinoma.     

Relationship between inactivation of p16 gene and gastric carcinoma

AIM: To investigate the relationship between inactivation of p16 gene and gastric carcinoma, and the mechanism of inactivation of p16 gene in gastric carcinogenesis. METHODS: 40 fresh tumor tissue specimens were taken from primary gastric cancer patients. Expression of P16 protein was detected by immunohistochemical method. Deletion and point mutation of p16 gene were analyzed by polymerase chain reaction (PCR) and DNA sequencing, respectively. RESULTS: The frequency of loss of P16 protein expression in the gastric cancer tissue, adjacent nontumor tissue, and distal normal tissue was 77.5 % (31/40), 55.0 % (22/40), and 17.5 % (7/40), respectively (P<0.005). Homozygous deletion of exon 1 and exon 3 was observed in two and three cases, respectively, giving an overall frequency of homozygous deletion of 12.5 %. All five cases had diffuse type gastric carcinoma. No p16 gene point mutation was detected. CONCLUSION: These findings suggest a close correlation between inactivation of p16 gene and gastric carcinoma. Further investigations are needed to testify the mechanism of inactivation of p16 gene in gastric carcinogenesis.     

Immunohistochemical analysis of pro-apoptotic PUMA protein and mutational analysis of PUMA gene in gastric carcinomas

BACKGROUND: Mounting evidence indicates that alteration of apoptosis is involved in the mechanisms of cancer development. PUMA, a pro-apoptotic member of Bcl-2 family, mediates p53-dependent and -independent apoptosis. AIM: The aim of this study was to explore whether alteration of PUMA protein expression is a characteristic of human gastric carcinomas. PATIENTS AND METHODS: We analysed expression of PUMA protein in 60 gastric adenocarcinomas by immunohistochemistry. Also, we examined PUMA gene mutation in the same tissues by a single-strand conformation polymorphism. RESULTS: PUMA protein expression was detected in 44 cases (73%) of the 60 gastric carcinomas, whereas it was not detected in normal gastric mucosal epithelial cells. The mutational analysis revealed no PUMA mutation in the gastric carcinomas. CONCLUSIONS: Our data suggest that PUMA mutation is not a direct target of inactivation in gastric tumourigenesis. Also, increased expression of PUMA in malignant gastric epithelial cells compared with normal mucosal epithelial cells suggested that PUMA expression may play a role in gastric tumourigenesis.     

Genomic alterations in primary gastric cancers analyzed by comparative genomic hybridization and clinicopathological factors

BACKGROUND/AIMS: Genetic changes during the oncogenesis and progression of gastric cancer remain unclear. The aim of our study was to analyze chromosomal aberrations in primary gastric cancers. METHODOLOGY: Using comparative genomic hybridization, we screened 47 primary gastric cancers for changes in the number of copies of DNA sequences. RESULTS: Gains of chromosome arms 20q (55%), 20p (36%), 17q (32%), 19q (30%) and 16p (30%), and losses of chromosome arms 4q (40%), 17p (40%), 5q (38%), 18q (30%) and 4p (28%) were detected most frequently. In addition, a high level of amplification was observed at 3q21 (2%), 6p21 (4%), 7q31 (6%), 8q23-24 (2%), 19q12-13 (2%), and 20q13 (2%). Among these alterations, the gain of 20q was the most frequent change. We then compared these changes with clinicopathological factors and identified signet ring cell carcinomas in 6 cases. Our study demonstrated no amplification of chromosome 20q in signet ring cell carcinoma in contrast to that in the other histologic types of gastric cancer. CONCLUSIONS: Our findings may be related to the morphologic and clinical features of signet ring cell carcinoma, and several oncogenes mapped on 20q may play an important role as determinants of the clinical and histologic features of gastric cancer.     

MTA1基因表达与人胃癌的浸润和转移

目的:探讨MTA1基因在胃癌及癌周组织中的表达及其表达水平与胃癌浸润和转移潜能的相关性.方法:采用荧光定量PCR及Western印迹技术,分别在mRNA和蛋白水平检测42例手术切除的人胃癌组织及癌旁组织中MTA1的表达,结合胃癌的临床生物学特征分析MTA1表达与胃癌病理类型、淋巴结转移的关系.结果:胃癌组织中MTA1mRNA相对量的表达显著高于癌旁胃黏膜组织(0.6711vs0.3940,P<0.01),蛋白水平表达与mRNA一致.低分化胃腺癌组织中的MTA1mRNA的相对量表达显著高于中高分化胃腺癌组织(0.7475vs0.3460,P<0.01),而伴有淋巴结转移的胃癌组织中MTA1mRNA的相对量表达明显高于不伴有淋巴结转移的胃癌组织(0.8128vs0.4933,P<0.01).结论:MTA1的表达与促进胃癌的转移相关,检测MTA1表达可作为预测胃癌生物学行为、判断胃癌患者预后的一个参考指标.     

Endoscopic features of early-stage signet-ring-cell carcinoma of the stomach

AIM: To identify the features of early signet ring cell gastric carcinoma using magnification endoscopy with narrow band imaging (NBI).METHODS: A retrospective review was conducted of 12 cases of early signet ring cell gastric carcinoma who underwent treatment in a single institution between January 2009 and April 2013. All patients had magnification endoscopy with NBI and indigo carmine contrast to closely examine the mucosal architecture, including the microvasculature and arrangement of gastric pits. Histologic examination of the final endoscopic submucosal dissection or gastrectomy specimen was performed and compared with the endoscopic findings to identify patterns specific to signet ring cell carcinoma.RESULTS: Twelve patients with early signet ring cell gastric carcinoma were identified; 75% were male, and average age was 61 years. Most of the lesions were stage T1a (83%), while the remainder were T1b (17%). The mean lesion size was 1.4 cm². On standard endoscopy, all 12 patients had a pale, flat lesion without any evidence of mucosal abnormality such as ulceration, elevation, or depression. On magnification endoscopy with NBI, all of the patients had irregularities in the glands and microvasculature consistent with early gastric cancer. In addition, all 12 patients exhibited the “stretch sign”, an elongation or expansion of the architectural structure. Histologic examination of the resected specimens demonstrated an expanded and edematous mucosal layer infiltrated with tumor cells.CONCLUSION: The “stretch sign” appears to be specific for signet ring cell carcinoma and may aid in the early diagnosis and treatment of this aggressive pathology.