【作者】 熊振芳；

【导师】 谭云山； 候英勇； 纪元；

【作者基本信息】 复旦大学 ， 病理学与病理生理学， 2010， 硕士

【摘要】 目的：1)了解胃印戒细胞癌黏液分泌性状、数量和分布,探讨黏液异质性表达的机制及其生物学意义。2)探讨胃、肠表型分型及其与K-ras基因突变和预后的相关性,评价K-ras基因突变作为胃印戒细胞癌分子靶向治疗靶点的可行性,为胃印戒细胞癌患者的治疗、预后评价提供有力的理论依据。方法：1)电话随访2000年～2008年在我院行胃癌根治术的胃印戒细胞癌患者163例,调查患者的生存状况,了解死亡患者的死亡时间和死亡原因。2)对163例癌组织和30例正常胃黏膜组织行黏液组化染色,检测两组中黏液表型表达状况；同时结合免疫组化Envision法检测胃黏膜上皮免疫表型标记MUC1、MUC5AC、MUC6和肠黏膜上皮免疫表型标记MUC2、CDX2的表达水平,并根据肿瘤细胞胃、肠黏膜上皮免疫表型标记物表达水平的差异,将胃印戒细胞癌分为三种类型：胃型印戒细胞癌(只表达胃免疫表型标记),肠型印戒细胞癌(只表达肠免疫表型标记),混合型印戒细胞癌(同时表达胃免疫表型和肠免疫表型标记)。3)抽提肿瘤组织基因组DNA, PCR-DNA直接测序方法检测163例癌组织中K-ras基因第12、13和61密码子突变状况。结果：1)163例患者有143例获得随访资料,随访率87.7%。62例患者生存,81例患者死亡。2)癌组织形态学观察查见Ⅰ型印戒细胞癌137例,Ⅲ型印戒细胞癌26例,无其他三种类型发现。3)163例癌组织和30例正常胃黏膜组织内中性黏液、唾液酸黏液和硫酸黏液检出率分别为69.9%(114/163)、42.3%(69/163)、19%(31/163)和100%(30/30)、0%(0/30)、0%(0/30)；两组中MUC1、MUC5AC、MUC6、MUC2、CDX2的阳性表达率分别为20.9%(34/163)、73.6%(120/163)、28.8%(47／163)、46.6%(76/163)、39.3%(64/163)和50%(15/30)、80%(24/30)、60%(18/30)、0%(0/30)、0%(0/30)。4)中性黏液、唾液酸黏液和硫酸黏液检出率两组间均有显著性差异(均P<0.05)；MUC1、MUC6、MUC2和CDX2的阳性表达率两组间均有显著性差异(均(P＜0.05);MUC5AC的阳性表达率两组间无显著性差异(P>0.05)。5)中性黏液更多见于肿块≤5.0cm病例,唾液酸黏液更多见于肿块>5.0cm患者；黏膜内癌中性黏液检出率显著高于黏膜下层浸润癌(P<0.05),相反,黏膜内癌唾液酸黏液和硫酸黏液检出率显著低于黏膜下层浸润癌(均P<0.05)；淋巴结转移组中性黏液检出率显著低于无淋巴结转移组(P<0.05),而唾液酸黏液检出率显著高于无淋巴结转移组(P<0.05)；(Ⅰ+Ⅱ)期癌组织内中性黏液检出率明显高于(Ⅲ+Ⅳ)期(P<0.05),而唾液酸黏液检出率则显著低于(Ⅲ+Ⅳ)期(P<0.05)。6)胃、肠表型标记表达水平与印戒细胞癌形态学分型无相关性(P＞0.05)。7)MUC2阳性表达与肿瘤浸润深度和淋巴结转移呈正相关性(P=0.001和P=0.002);CDX2阳性表达与肿瘤大小、浸润深度以及肿瘤TNM分期呈正相关(P=0.004和P=0.001)；MUC5AC阳性表达与肿瘤浸润深度呈负相关(P=0.001)。8)根据胃、肠上皮免疫表型表达差异,查见胃型印戒细胞癌、混合型印戒细胞癌、肠型印戒细胞癌分别为63例(38.6%)、71例(43.5%)、29例(17.9%)。9)肠型印戒细胞癌更多见于肿块>5.0cm、有黏膜下层浸润、淋巴结转移和(Ⅲ+Ⅳ)期的病例中(均P<0.01)。10)163例癌组织中,K-ras基因突变率为12.27%(20/163),所有突变位点均位于12密码子,突变类型包括：GGT→GTT(8例),GGT→GAT(10例),GGT→AGT(1例),GGT→TGT(1例)。13和61密码子未检出突变。11)K-ras基因突变更多见于MUC5AC阴性、MUC6阴性以及肠型印戒细胞癌中。12)生存分析显示,MUC2阳性患者中位生存期明显低于MUC2阴性患者(P<0.05)；非胃型(肠型和混合型)印戒细胞癌患者中位生存期明显低于胃型印戒细胞癌(P<0.05)。13)单因素分析显示肿瘤浸润深度和MUC2阳性表达与预后相关(均P<0.05),肿瘤大小、患者年龄、淋巴结转移等因素与预后无相关性。多因素分析显示肿瘤浸润深度和MUC2阳性表达可以作为独立的预后因素(P<0.05)。结论：1)胃、肠表型标记及其分型与胃印戒细胞癌的生物学行为和预后密切相关,肠型胃印戒细胞癌临床生物学行为和预后均较胃型印戒细胞癌差,该分型弥补了传统形态学分型的不足。建立统一的、科学合理的免疫表型分型标准,对印戒细胞癌有重要价值。2)本研究首次发现在胃印戒细胞癌中,K-ras基因突变率为12.27%,12密码子是突变热点。3) K-ras基因突变更多见于肠型病例,提示其在胃、肠表型分化中可能起到一定作用,。4)胃、肠表型标记的胃印戒细胞癌分型可能存在不同的遗传背景,研究其潜在的分子机制有助于明确肿瘤的组织发生,并对指导患者治疗可能具有一定的参考价值。更多还原

【Abstract】 Objective:1) To elucidate the characteristics and distribution of mucus in SRCC and to investigate the mechanism of heterogeneity in mucin expression of tumor cells.2) To investigate phenotypic classification of SRCC and its relationship with K-ras mutation and prognosis, estimate feasibility of K-ras gene mutation as target for molecular targeted therapy (MTT) and provide a theoretical basis to therapy and prognostic evaluation.Methods:1) A total of 163 patients with gastric SRCC who underwent curative surgery from 2000 to 2008 were followed up by telephone in this study.2) Mucin histochemical method was performed in 163 cases of SRCC and 30 cases of normal mucosa. Meanwhile, Immunohistochemistry was performed with MUC1, MUC5AC, MUC6 antibodies as gastric phenotypic markers and MUC2, CDX2 antibodies as intestinal phenotypic markers, according to the expression of phenotypic markers, tumors were classified into three different types:gastric type, intestinal type and mixed type.3) Genomic DNA was extracted by standard method, K-ras gene was amplified by polymerase chain reaction (PCR) and analyzed mutation in codon12,13 and 61 by DNA direct sequencing.Results:1) Clinical follow-up were available for 143 patients (87.7%),62 of them were alive, and 81 of them were die.2) Histopathological findings:cases of typeⅠSRCC were 137, while cases of typeⅢSRCC were 26.3) The cases containing neutral mucus, sialomucin or sulfomucin in carcinoma and normal mucosa were 69.9%(114/163),42.3% (69/163),19%(31/163) and 100%(30/30),0%(0/30),0%(0/30) respectively. The expression rates of MUC1, MUC5AC, MUC6, MUC2 and CDX2 in 163 cases of SRCC and 30 cases of normal gastric mucosa were 20.9%(34/163),73.6%(120/163), 28.8%(47/163),46.6%(76/163),39.9%(64/163) and 50%(15/30),80%(24/30),60%(18/30), 0%(0/30),0%(0/30) respectively.4) The cases containing neutral mucus in carcinoma was significantly lower than that in normal mucosa (P＜0.05). Inversely, the cases containing sialomucin or sulfomucin in carcinoma were significantly higher than that in normal mucosa (P＜0.05).5) The positive rates of MUC1 and MUC6 in carcinoma were significantly lower than that in normal mucosa (P＜0.05). Inversely, the rates of MUC2 and CDX2 expression in carcinoma were significantly higher than that in mucosal carcinoma (P＜0.01 and P＜0.05). The cases containing neutral mucus in intramucosal carcinoma, carcinoma with tumor size≤5.0cm, carcinoma without lymph node metastasis and with (Ⅰ+Ⅱ) stages were more than that in submucosal carcinoma, carcinoma with tumor size＞5.0cm, carcinoma with lymph node metastasis and (Ⅲ+Ⅳ) stages (P＜0.05). Inversely, the cases containing sialomucin or sulfomucin in intramucosal carcinoma were less than that in submucoasl carcinoma (P＜0.05). The cases containing sialomucin or sulfomucin in carcinoma with lymph node metastasis and (Ⅲ+Ⅳ) stages were significantly more than that without lymph node metastasis and (Ⅰ+Ⅱ) stages (P＜0.05).6) There was no relationship between phenotypic markers expression and morphological classification of SRCC.7) The expression rate of MUC2 was positive related to depth of invasion and lymph node metastasis (P=0.001 and P=0.002). The expression rate of CDX2 was positive related to tumor size, depth of invasion and TNM stage (P=0.004 and P=0.001). The expression rate of MUC5AC was negative related to depth of invasion (P=0.001).8) According to the expression of phenotypic markers,63 cases (38.6%) were gastric type,71 cases (43.5%) were mixed type,29 cases (17.9%) were intestinal type.9) More cases of intestinal type of SRCC had tumor size＞5.0cm, wall invasion deeper than submucosa layer, lymph node metastasis and (Ⅲ+Ⅳ) stage (P＜0.01) than other types.10) The frequency of K-ras gene mutation was 12.27%(20/163), all mutational loci were found in codon 12. Among the 20 cases of mutation,8 cases showed mutation of GGT→GTT,10 cases showed mutation of GGT→GAT,1 case showed mutation of GGT→AGT,1 case showed mutation of GGT→TGT. No mutation at codon 13,61 was deteted.11) More K-ras gene mutation was found in cases with MUC5AC (-), MUC6 (-) and intestinal type of SRCC.12) Survival analysis showed that median survival period of cases with MUC2 (+) was shorter than cases with MUC2 (-) (P＜0.05). Intestinal and mixed types were associated with shortened median survival period (P＜0.05).13) Univariate survival analysis showed that depth of invasion and MUC2 expression were prognostic factors, while multivariate survival analysis showed that depth of invasion and MUC2 expression were independent prognostic factors (P＜0.05).Conclusions:1) Phenotypic classification was correlated with biological behaviors and prognosis in SRCC.2) The frequency of K-ras gene mutation was 12.27%, all mutational loci were found in codon 12.3) K-ras gene mutation was more common in intestinal type, indicated that it may play an important role in phenotypic differentiation.4) There had different genetic pathways according to the phenotypic marker expression patterns and it might play a role in the tumorigenesis of the SRCC.更多还原