Mucin phenotype and molecular genetic analysis of gastric cancer

胃癌的遗传学分析总结在两个部分。I.高分化早期胃腺癌的粘蛋白表型和遗传分析：高分化早期胃腺癌病例分为胃、肠和胃/肠混合表型，并进行遗传分析。1)具有胞浆粘蛋白的分化良好的粘膜肿瘤可能会变得分化程度较低，并可能通过遗传进展而释放粘蛋白。2)3）部分病例同时具有胃和肠表型的癌灶。这是由亚克隆出现通过遗传进展和/或遗传分歧。4)在肠化生和甚至正常出现的粘膜以及癌部分中检测到hMLHl的甲基化。总之，有许多分化良好的腺癌病例显示胃和混合表型。这些表型多样性是由双向 ...更多信息 肿瘤克隆的表型能力以及遗传进展和/或遗传趋异。具有混合表型的腺癌细胞可从具有不完全化生的受损粘膜或具有混合表型能力的粘膜细胞中出现。此外，我们确定了从粘膜高分化癌进展到低分化形式的遗传途径。二.产甲胎蛋白胃癌（AFP-GC）的遗传分析：AFP-GC是一种罕见的侵袭性腺癌，表现出复杂的组织学图像，包括髓样、肠母细胞和肝样分化。本研究对20例AFP-GC的多个病灶进行了显微解剖和洛丢失分析。大多数肿瘤为单克隆性，伴有广泛的洛缺失（平均等位基因丢失分数为0.79）。洛缺失的异质性模式提示髓样癌、肠母细胞癌和肝样癌灶产生AFP可能通过遗传进展和/或遗传分化而进化。少

Genetic analysis of gastric cancer is summarized in two parts. I. Mucin phenotype and genetic analysis of well differentiated early gastric adenocarcinoma : Well differentiated early gastric adenocarcinoma cases were classified into gastric, intestinal, and mixed gastric/intestinal phenotype, and were subjected to genetic analysis. 1) Well differentiated mucosal tumor with cytoplasmic mucin may become less differentiated and may loose mucin by genetic progression. 2) There are monoclonal tumor cells possessing biphasic phenotype, 3) Some cases show carcinoma foci with gastric and intestinal phenotype side by side. This is caused by subclonal emergence through genetic progression and/or genetic divergence. 4) Methylation of hMLHl was detected in intestinal metaplasia and even normal appearing mucosa as well as carcinoma portions. Altogether, there are many well differentiated adenocarcinoma cases showing gastric and mixed phenotype. These phenotypic diversity is conferred by bidirection … More al phenotypic ability of the tumor clones as well as genetic progression and/or genetic divergence. Adenocarcinoma cells with mixed phenotype may emerge from damaged mucosa with incomplete metaplasia or mucosal cells with mixed phenotypic ability. Furthermore, we identified genetic pathways from mucosal well differentiated carcinoma progressing to less differentiated forms. II. Genetic analysis of Alpha fetoprotein producing gastric cancer (AFP-GC) : AFP-GC is an unusual form of aggressive adenocarcinoma showing complex histological pictures including medullary pattern, enteroblastic, and hepatoid differentiation. In the present study, multiple foci from 20 cases of AFP-GC were microdissected and LOH analysis was performed. Most tumors were single clonal with extensive LOH (an average fractional allelic loss of0.79). Presence of heterogeneous patterns of LOH suggested that the AFP producing medullary, enteroblastic and hepatoid carcinoma foci may evolve through genetic progression and/or genetic divergence. Less