Molecular biology and analysis of related genes of apoptosis in human gastric carcinomas and precancerous lesions

1.活体分析1)正常胃粘膜中极少见凋亡细胞，而化生腺体深层有少量凋亡细胞。对30例管状腺瘤进行细胞凋亡数或凋亡指数(AI)的计数。重度非典型性管状腺瘤的AI高于轻度非典型性管状腺瘤。对15例同时发现腺瘤和癌的手术切除胃进行AI分析。前者AI为4.9±2.1，后者为3.9±1.1，差异有统计学意义(P&lt；0.05)。15例携带野生型P53的胃癌的AI为3.8±1.4，15例携带突变型P53的胃癌的AI为4.9±1.2，后者显著高于后者(P&lt；0.0 5)。3)17例EB病毒相关性淋巴间质癌的AI显著低于其他组织类型的胃癌(P&lt；0.0 5)。4)AI显著增加…。结果：1.术前持续静脉注射5-FU 500 mg/d，连续7天，10例患者O6.1±3.6，明显高于未接受5-FU治疗的10例(3.2±1.8：P&lt；0.05)。1)1 mM-5FU可不同程度地诱导野生型P53基因阳性的MKN-74和MKN-45细胞发生凋亡，而携带突变型P53基因的MKN28细胞和缺失KATO-III型P53基因的MKN28细胞则无此作用。Western印迹分析显示MKN-74和MKN-45.2细胞中P53和P21表达增加。携带野生型p53基因的MKN-74和MKN-45的表达水平最高。100 ng/ml的抗Fas抗体诱导细胞凋亡，其AI值与Fas抗原的表达水平呈正相关。3)紫杉醇作用于人胃癌细胞系G2/M期，诱导细胞发生凋亡。紫杉醇的敏感性与P53基因状态无关。这些结果表明，多种刺激可能不同程度地诱导胃癌细胞发生凋亡，而与凋亡相关的信号转导部分依赖于P53蛋白。较少

1. in vivo analysis1) Apoptotic cells were extremely rare in normal gastric mucosa, whle a few apoptotic cells were present in deeper portions of the metaplastic glands. The number of apoptotic cells or apoptotic index (AI) was counted in 30 tubular adenomas. AI was higher in the tubular adenomas with severe atypia than in those with mild atypia. AI was analyzed in 15 surgically removed stomachs in which adenoma and carcinoma were found simultaneously. AI was 4.9+2.1 in the former and 3.9+1.1 in the latter, the value being significantly different (P<0.05). On the other hand, proliferative index (PI) was higher in the carcinomas.2) AI was 3.8+1.4 in 15 gastric cancers carrying wild type p53 and 4.9+1.2 in 15 cancers carrying mutated p53 gene, the value being significantly higher in the latter (P<0.05).3) AI was significantly lower in 17 EB-virus related gastric carcinomas with lymphoid stroma than other any histological type of gastric carcinomas (P<0.05).4) AI increased significantly t … More o 6.1+3.6 in 10 patients received continuous intravenous 5-FU at 500mg/day for 7 days preoperatively, compared with 10 patients without 5-FU (3.2+1.8 : P<0.05).2. in vitro analysis1) 1mM-5FU variably induced apoptosis in MKN-74 and MKN-45, both of which carries wild type p53 gene, but not MKN28 carrying mutated p53 gene and KATO-III p53 gene being deleted. Western blot analysis showed increasing of P53 and P21 in MKN-74 and MKN-45.2) Fas was detected to be expressed variably in the six human gastric carcinoma cell lines. The expression level was highest for MKN-74 and MKN-45 carrying wild type p53 gene. Anti-Fas antibody of 100ng/ml induced apoptosis, the value of AI being correlated with the expression levels of FAS antigen.3) Treatment with taxol of 1 uM arrested in G2/M,followed by apoptosis in the human gastric carcinoma cell lines. Susceptibility to taxol did not correlate with p53 gene status.These results overall indicate that gastric cancer cells might be variably induced apoptosis by a variety of stimuli, and signal transduction relating apoptosis partly depends on the p53 protein. Less