Wang Gang-Shi, Wang Meng-Wei, Wu Ben-Yan, You Wei-Di, Yang Xin-Yan
Department of Gastroenterology, General Hospital of Chinese PLA, Beijing 100853, China.
World J Gastroenterol. 2003 Jan;9(1):30-4. doi: 10.3748/wjg.v9.i1.30.
To clone genes that may predispose us to human gastric cancer and to analyze it's expression in gastric tissues.
Specimens of paired tumor, paratumor and normal gastric mucosa tissues collected from fifteen patients who suffered from stomach antrum adenocarcinoma were used for analysis. Seven out of the fifteen cases were first studied by fluorescent differential display reverse transcription polymerase chain reaction (DDTR-PCR) analysis. The differentially expressed bands of interest were cloned, analyzed by Northern blot, sequencing and RT-PCR. Through BLAST, the sequencing results were compared with GenBank database for homology analysis. In situ hybridization with DIG-labeled cRNA probes was used to analyze the expression of interesting cDNA bands in paraffin embedded paired normal gastric mucosa and cancer tissues isolated from 30 gastric adenocarcinoma patients.
DDRT-PCR showed that one of the interesting cDNA bands, which was named W2, expressed much higher in all seven tested tumor and paratumor samples than in their normal counterparts, it was sub-cloned into a pGEM-T Easy vector. Two subclones were subsequently obtained. One of the subclone, GCRG224, was studied further. The sequencing result showed that GCRG224 consisted of 1 159 base pairs and had one open reading frame (ORF). It located at human chromosome 11q14. No homologue was found in GenBank database with GCRG224-ORF. This nucleotide sequence data were submitted to GenBank with accession No. AF438406. RT-PCR showed that GCRG224 expressed higher in 11/15 gastric cancer tissues than in non-tumor tissues. However, the result of Northern blot analysis showed a higher GCRG224 expression in the non-tumor tissue than in the tumor one. Human multiple tissue Northern blot analysis revealed that GCRG224 also expressed in human normal colon tissue, and peripheral blood leukocyte. In situ hybridization analysis showed that only 5/30 adenocarcinoma, 3/18 dysplasia and 6/18 intestinal metaplasia showed higher GCRG224 expression level than the normal gastric glands. However, GCRG224 was over-expressed predominantly in 26/30 cases of normal mucosal epithelium.
A novel gene named GCRG224 was identified from human gastric mucosal tissue. It overexpressed in almost all gastric mucosal epithelium but only a small portion of cancer and precancerous leisions. The role of GCRG224 expression in gastric epithelium needs further study.
克隆可能使我们易患人类胃癌的基因，并分析其在胃组织中的表达。
收集15例胃窦腺癌患者的肿瘤、癌旁和正常胃黏膜组织配对标本进行分析。15例中的7例首先通过荧光差异显示逆转录聚合酶链反应（DDTR-PCR）分析进行研究。对感兴趣的差异表达条带进行克隆，通过Northern印迹、测序和RT-PCR分析。通过BLAST将测序结果与GenBank数据库进行比较以进行同源性分析。使用地高辛标记的cRNA探针进行原位杂交，以分析从30例胃腺癌患者分离的石蜡包埋的配对正常胃黏膜和癌组织中感兴趣的cDNA条带的表达。
DDRT-PCR显示，其中一个感兴趣的cDNA条带，命名为W2，在所有7个测试的肿瘤和癌旁样本中的表达均远高于其正常对应物，将其亚克隆到pGEM-T Easy载体中。随后获得了两个亚克隆。对其中一个亚克隆GCRG224进行了进一步研究。测序结果显示GCRG224由1159个碱基对组成，有一个开放阅读框（ORF）。它位于人类染色体11q14。在GenBank数据库中未发现与GCRG224-ORF同源的序列。该核苷酸序列数据已提交至GenBank，登录号为AF438406。RT-PCR显示，GCRG224在11/15的胃癌组织中的表达高于非肿瘤组织。然而，Northern印迹分析结果显示，GCRG224在非肿瘤组织中的表达高于肿瘤组织。人类多组织Northern印迹分析显示，GCRG224也在人类正常结肠组织和外周血白细胞中表达。原位杂交分析显示，仅5/30的腺癌、3/18的发育异常和6/18的肠化生显示GCRG224表达水平高于正常胃腺。然而，GCRG224在26/30例正常黏膜上皮中主要过度表达。
从人胃黏膜组织中鉴定出一个名为GCRG224的新基因。它在几乎所有胃黏膜上皮中过度表达，但仅在一小部分癌症和癌前病变中表达。GCRG224在胃上皮中的表达作用需要进一步研究。
