1.结直肠锯齿状病变中RUNX3的表达及其基因多态性的观察研究；2.结直肠纤维绒毛锯齿状腺瘤的病理形态学及免疫组织化学特征

【作者】 王琳；

【导师】 王鲁平；

【作者基本信息】 山西医科大学 ， 病理学与病理生理学， 2011， 硕士

【摘要】 [背景与目的]锯齿状病变是一组以上皮呈锯齿状结构为特征的结直肠息肉/腺瘤,因其具有恶变为结直肠腺癌的潜能,近年来日益受到临床病理学工作者的关注。2010年新版WHO消化系统肿瘤分册将锯齿状息肉和息肉病明确分为增生性息肉(Hyperplastic polyps,HPs),广基锯齿状腺瘤/息肉(Sessile serrated adenoma/polyp,SSA/P),传统锯齿状腺瘤(Traditional serrated adenoma,TSA)三种类型。其中TSA和SSA具有明确恶变潜能,不同类型的HPs与也有类似于TSA及SSA的基因改变。锯齿状通路是一个多因素、多阶段、多基因改变渐进性累积的复杂过程,在此演变过程中涉及多种癌基因和抑癌基因,具体的发病机制迄今未完全明了。Runx转录因子3 (Runt-related transcription factor 3,RUNX3)基因是近年来新发现的一种抑癌基因,已被证实在多种人类肿瘤中存在RUNX3基因的异常。有研究发现RUNX3基因与人类消化系统肿瘤的发生关系更为密切,但是RUNX3基因在锯齿状病变发生和恶变过程中的作用尚不明确。RUNX3位于人类染色体的1p36.1,主要表达于消化道上皮细胞、血液细胞、间叶细胞、神经细胞等。已有研究证实RUNX3基因通过调节细胞周期和诱导细胞凋亡对肿瘤造成抑制,RUNX3基因的失活可能会造成癌症的发生。目前关于RUNX3在结肠癌中的作用已有不少文献,但有关RUNX3在锯齿状病变中作用的研究报告很少,国外Subramaniam等曾通过免疫组织化学方法比较发现HP和TSA中RUNX3的阳性表达较正常结肠组织和管状腺瘤(Tubular adenoma,TA)中有所下降,而国内尚没有对RUNX3在锯齿状病变中的研究报告。本研究通过观察锯齿状病变在RUNX3的免疫组织化学表达以及分析锯齿状腺瘤(Serrated adenoma,SA)中RUNX3(rs2236851,C/T)位点多态性,并观察上述两者的关系,从而对RUNX3在锯齿状病变发生与癌变途径中的作用进行初步探讨。[方法]收集北京军区总医院、海军总医院、解放军第二五二医院、河北省巨鹿县医院、北京中医药大学东直门医院2002年10月至2009年9月间病理诊断为结直肠各类息肉和腺瘤切片共5347例,所有切片按WHO及文献标准,3名病理医师4—5轮阅片,从中筛选出锯齿状病变共258例。对上述258例锯齿状病变进行组织学诊断及分类,从中筛选出TSA32例,SSA/P 8例,HP25例,并收集大肠癌(Colorectal cancer,CRC) 20例、TA25例、正常大肠组织25例作为对照组,所有组织切片均进行免疫组织化学染色,观察RUNX3的表达情况。另从上述258例锯齿状病变中随机挑选出50例SA(包括TSA40例,SSA/P10例)作为实验组,并收集正常大肠组织20例作为正常对照组,运用PCR-SSP方法研究RUNX3(rs2236851,C/T)的多态性;并从SA实验组中随机抽取30例SA进行免疫组织化学染色,运用IPP图像分析系统进行免疫组织化学阳性表达的半定量分析,分析基因型与RUNX3表达之间的关系。[结果]对RUNX3在正常组、TA组、HP组、TSA组、SSA组以及CRC组的免疫组织化学表达进行统计学分析,结果显示:RUNX3在TSA、SSA、大肠癌三组阳性率比正常对照组明显降低,差异具有统计学意义;RUNX3在SSA组与TA组之间、CRC组与TA组之间也具有统计学差异。TSA组与TA组之间虽然没有统计学差异,但TSA组RUNX3阳性表达率明显低于TA组。对RUX3基因rs2236851位点多态性分析及IPP图像分析系统半定量分析显示:SA实验组T等位基因的频率明显高于正常对照组,RUNX3基因rs2236851位点可能与SA密切相关;分析SA基因型与RUNX3表达的关系发现TC基因型SA患者的RUNX3阳性表达明显降低。[结论]1.免疫组织化学结果显示RUNX3在锯齿状病变中表达阳性率降低,提示其可能是SA发生和恶变过程中的必要条件。2.基因多态性分析结果提示RUNX3 (rs2236851, C/T)位点可能与SA密切相关,TC基因型SA患者的RUNX3阳性表达降低更明显。[背景与目的]锯齿状病变是一组以上皮呈锯齿状结构为特征的结直肠息肉/腺瘤。2010年版WHO消化系统肿瘤分册将锯齿状病变明确分为增生性息肉(Hyperplastic polyps,HPs),广基锯齿状腺瘤/息肉(Sessile serrated adenoma/ polyp,SSA/P),传统锯齿状腺瘤(Traditional serrated adenoma,TSA)三种类型。其中HP根据粘液类型又分为微小泡状型HP(microvesicula HP,MVHP)、杯状细胞型HP(goblet cellric HP,GCHP)、粘液缺乏型HP(mucin poor HP,MPHP);SSA/P根据细胞异型性分为不伴细胞异型增生型SSA/P及伴有细胞异型增生型SSA/P。近来,在锯齿状病变中,有研究者发现存在一类形态更为特殊的锯齿状病变,其形态除具有典型的锯齿状结构外,还兼有长纤维绒毛状突起的特征。2010年版WHO消化系统肿瘤分册将这类锯齿状病变归为TSA中较罕见的一个亚型,称作“纤维绒毛锯齿状腺瘤”(Filiform serrated adenoma,FSA)。目前国内外对FSA的了解与研究甚少,多数病理及临床医师对其更是鲜有认识。因此本研究通过探讨FSA的临床病理学形态学特征以及免疫组织化学特征,旨在增强对FSA的认识,加强对患者的预后管理。[方法]收集北京军区总医院、海军总医院、解放军第二五二医院、河北省巨鹿县医院、北京中医药大学东直门医院2002年10月至2009年9月间病理诊断为结直肠各类息肉和腺瘤切片5347例,所有切片按WHO及文献标准,3名病理医师4-5轮阅片,从中筛选出FSA共18例,同时收集临床相关资料并观察病理学特征。对FSA11例,NFSA20例(其中TSA15例, SSA/P5例),HP20例,VTA20例分别进行免疫组化Ki-67、p53、β-Catenin、CK7、CK20、CDX-2、RUNX3染色。[结果]观察结果显示FSA占所收集全部结直肠息肉/腺瘤的0.34%,占锯齿状病变的6.98%;FSA多发于老年人,部位多位于左半结肠,尤其直肠部位。组织学观察结果显示其表面可见许多细长的纤维状绒毛状突起,隐窝被覆有异型增生的上皮细胞,伴有典型锯齿状改变;该类突起形似绒毛管状腺瘤,但其长度比绒毛管状腺瘤长;多数病例的突起末端可见明显间质水肿,严重者膨大呈“球茎”状改变;FSA异型增生程度较NFSA、VTA要高,差异有统计学意义。免疫组织化学染色结果显示p53、Ki-67、RUNX3在FSA中的表达与其他组间存在统计学差异;β-Catenin、CK7、CK20、CDX-2在FSA中的表达与其他组间未见统计学差异。[结论]1.FSA是特殊类型的锯齿状腺瘤,多发于左半结肠尤其直肠部位。2.病理形态学观察结果提示FSA以“长纤维绒毛”的典型特征区别于其他锯齿状病变。与NFSA、VTA相比,其异型增生程度更高。3.免疫组织化学结果提示FSA具有较高增殖活性,Ki-67在FSA中的表达提示FSA可能具有更高的恶变潜能。更多还原

【Abstract】 [Background and Objective]Serrated lesions are a group of colorectal adenoma/polyps characterized morphologically by a serrated architecture of the crypt epithelium.Because of their malignant potential, serrated lesions become Research focus and get more attention by clinical Pathologist in recent years.The lesions include hyperplastic polyps(HPs),sessile serrated adenoma/ polyp (SSA/P) and traditional serrated adenoma(TSA) in WHO(2010).TSA and SSA have malignant potential,and different types of HPs also has similar genetic changes like TSA and SSA. Runt-related transcription factor 3 (Runx3) is considered to be a tumor suppressor gene, and have been found that there are RUNX3 gene abnormalities in variety human tumors in recent years. Studies have found that Runx3 is more closely related with human digestive system tumors, But the effection of RUNX3 gene in serrated lesions is not clear.RUNX3 is located on human chromosome 1p36.1,mainly express in gastrointestinal epithelium cells, blood cells, mesenchymal, nerve cells, etc. Research showed RUNX3 could inhibit growth of tumors by regulate cell cycle and induce apoptosis of tumor cell. In this study,the immunohistochemical expression and genetic polymorphism analysis of RUNX3 were observed in serrated lesions, the relationship between them were discussed, and the effection of RUNX3 in serrated pathway were explored.[Methods]A total of 5347 cases of colorectal polyps from five hospitals during a five-year period were retrospectively reviewed. The serrated lesions were classified based on WHO standards and literature. Amongst 5347 colorectal polyps studied,258 cases of serrated lesions were found. Amongst 258 cases of serrated lesions,32 cases of TSA, 8 cases of SSA/P and 25 cases of HP were selected. 25 cases of TA, 25 cases of normal colorectal tissues and 20cases of invasive adenocarcinoma were selected as the controls.All tissue sections were stainned using RUNX3 antibody by immunohistochemical methods.Besides, 50 cases of SA (including 40 cases of SA and 10 cases of SSA/P) and 20 cases of normal colorectal tissues were selected as the controls.Polymorphisms of RUNX3(rs2236851,C/T ) were genotyped by PCR-SSP. The relationship between immunohistochemical expression and genetic polymorphism were explored by IPP methods.[Results]The positive rate of RUNX3 in TSA,SSA and CRC were lower than in normal group.There were significant differences between the TSA,SSA,CRC and normal group.The significant differences also were observed between SSA,CRC and TA.The study of RUNX3 (rs2236851,C/T) polymorphism and the semi-quantitative analysis using IPP software was showed that the frequency of T allele was significantly higher in serrated adenoma(SA) than the normal control group. The RUNX3(rs2236851,C/T) was closely related with SA and the immunohistochemical expression of RUNX3 was lower in SA with TC genotype.[Conclusions]1. Immunohistochemistry expression results showed that the positive rate of RUNX3 expression is reduced in serrated lesions.It was a necessary events for SA changing into malignant lesions.2. The results of RUNX3 genetic polymorphism analysis suggest that RUNX3 (rs2236851, C / T) was closely related with the SA, the expression of RUNX3 in SA (TC genotype) was reduced. [Background and Objective]Serrated lesions are a heterogeneous group of lesions characterized morphologically by a serrated architecture of the epithelial compartment.The lesions include hyperplastic polyps(HPs),sessile serrated adenoma/ polyp (SSA/P) and traditional serrated adenoma(TSA) in WHO(2010). according to the type of mucus, HPs were divided into microvesicula HP (MVHP), goblet cellric HP (GCHP) and mucin poor HP ( MPHP). And according to cell atypia, the SSA/P were divided into SSA/P with dysplasia and SSA/P without dysplasia.Some studies reported an unusual type of TSA with long filiform projections lined by neoplastic epithelium with a serrated contour. These lesions were called Filiform Serrated Adenoma (FSA) in WHO( 2010). At present, domestic and international research with FSA is uncommon and the knowledge about these lesions was little understanding among clinical physicians and pathologists. Most of the pathological and clinical physicians to understand it even less.Therefore, this study discusses the clinical and pathological features of FSA and explore the immunohistochemical chang. Aim to help clinical pathologists enhanced understanding of FSA and to improve the management of patients.[Methods]A total of 5347 cases of colorectal polyps/adenomas from five regional hospitals in five years were retrospectively reviewed and 18 cases of FSA were selected. 20 cases of NFSA(including 15 cases TSA and 5 cases of SSA/P),20 cases of HP and 20 cases of VTA were randomly selected as control group. The clinical pathologic feature of FSA were observed.The expression of Ki-67, p53, CK7,CK20, CDX2, beta-catenin and RUNX3 in FSA,NFSA,HP and VTA were compared by immunohistochemical stain.[Results]Observation of clinical feature showed that FSA account for 0.34% of 5347 colorectal polyps/adenomas and account for 6.98% of 258 serrated lesions.FSA was tend to occur in older adults, and showed a strong predilection for developing in the left colon, especially the rectum. Observation of pathological features showed that FSA with long filiform projections lined by neoplastic epithelium with a serrated contour. The filiform projections of FSA were longer than the villi present in typical VTA .Marked stromal edema was present and the "bulb"-like change was showed in swelling of Severe cases. There was statistically significant difference between FSA and NFSA in the degree of dysphasia(p<0.05). The expression of Ki-67,p53,RUNX3 showed significant difference among FSA ,NFSA,HP and VTA (P<0.05); while the difference among expression ofCK7,CK20,CDX2 and beta-catenin in FSA ,NFSA,HP and VTA were not observed (P>0.05).[Conclusions]1. Observation showed that FSA is an uncommon type of serrated adenoma, shows a strong predilection located in the left colon,especially in rectum.2. Pathological observation results show that FSA has long filiform projections lined by neoplastic epithelium with a serrated contour unlike traditionalSA,.3. Immunohistochemical results suggest that FSA may has higher proliferation activity and higher malignant transformation potential.更多还原