胰腺导管腺癌、慢性胰腺炎及正常胰腺组织中胰腺上皮内瘤变的比较研究

目的探讨胰腺导管腺癌、慢性胰腺炎和正常胰腺组织中各级别PanIN的发生率以及与临床病理学参数间的关系.方法回顾性研究长海医院2001年1月～ 2003年12月间外科切除和同期尸检获得的250例胰腺标本中PanIN的发生情况,并联系临床病理指标进行相关分析.结果 250例胰腺标本中,有156例存在PanIN病变,发生率62.4%.其中,胰腺导管腺癌、慢性胰腺炎和正常胰腺组织中PanIN的发生率分别为75.6%、46.0%和30.0%,胰腺导管腺癌PanIN发生率明显高于慢性胰腺炎及正常胰腺组织(P < 0.01);慢性胰腺炎中高级别PanIN发生率明显高于正常胰腺组织(P < 0.05).PanIN-3仅在胰腺导管腺癌和慢性胰腺炎中见到.胰腺导管腺癌中,有烟酒嗜好和(或)糖尿病者高级别PanIN的发生率53.7%,明显高于对照组29.4%(P < 0.01).PanIN的发生率以61 ～ 70岁年龄组为最高.结论胰腺导管腺癌、慢性胰腺炎和正常胰腺组织中PanIN的发生率逐渐增加,程度逐渐加重,支持胰腺癌发生的分子模型.     

胰腺癌513例神经浸润的病理分析

目的 探讨胰腺癌神经浸润的特征及其与其他临床病理参数之间的关系.方法 光镜下观察491例胰腺导管腺癌、22例其他胰腺恶性肿瘤、41例胰腺良性病变和21例慢性胰腺炎组织中的神经浸润状况,分析其与其他病理学指标的相关性.结果 胰腺导管腺癌的神经浸润率为74%,显著高于其他类型恶性肿瘤的23%(P＜0.01).导管腺癌癌细胞通常穿越外周神经中膜到达内部的神经纤维束,有的甚至横断整根神经纤维.但神经浸润与导管腺癌的分化程度无关.52%的胰腺导管腺癌癌旁组织呈慢性炎症改变,且程度严重,远高于其他类型胰腺癌(14%)及胰腺良性病变(15%)的慢性炎症发生率(P＜0.01).胰腺导管腺癌淋巴细胞浸润神经的发生率为65%,远高于其他恶性肿瘤的36%和胰腺良性病变的22%(P＜0.01).胰腺导管腺癌的神经浸润与癌旁慢性胰腺炎症以及淋巴细胞浸润神经均相关,但与淋巴结转移无关.结论 神经浸润是胰腺导管腺癌特征性的生物学行为之一.     

胰腺导管腺癌组织中WT1,IGF-IR表达与细胞凋亡的关系

目的:研究胰腺导管腺癌组织中WT1,IGF-IR的表达与细胞凋亡关系．方法:应用免疫组化技术检测WT1,IGF-IR在49例胰腺导管腺癌及15例正常胰腺组织中的表达,并应用TUNEL法检测细胞凋亡,计算凋亡指数(AI)．结果:WT1,IGF-IR在正常胰腺组织中的阳性表达率分别为26．67％(4／15)、40．00％(6／15);在胰腺导管腺癌组织中的阳性表达率分别为71．43％(35／49)、77．55％(38／49),两者在癌组织中的表达分别明显高于其在正常胰腺组织中的表达(P<0．05),且在癌组织中的表达呈正相关(r=0．385,P<0．05)．正常胰腺组织及癌组织中的AI分别为0．41±0．13、5．93±4．18,两者比较有显著性差异(P<0．05),癌组织中AI随组织分化程度的升高而升高．IGF-IR表达阳性组的AI显著低于阴性组(4．11±3．68 vs 12．21±5．67,P<0．01)．结论:胰腺导管腺癌组织中IGF-IR的高表达抑制细胞凋亡,WT1,IGF-IR的高表达以及细胞凋亡的减少可能在胰腺导管腺癌的发生发展中起重要作用．     

脑源性神经营养因子在胰腺导管腺癌中的表达及其临床意义

目的 探讨脑源性神经营养因子（BDNF）在胰腺导管腺癌中的表达及其临床意义.方法 采用免疫组化SP法检测46例胰腺导管腺癌、38例胰腺良性疾病及20例正常胰腺组织中的BDNF表达,应用蛋白质印迹法和RT-PCR法检测BDNF蛋白及mRNA表达量,并分析BDNF表达与胰腺导管腺癌临床病理参数的相关性.结果 胰腺导管腺癌组织中BDNF阳性表达率为52.2％ （24/46）,胰腺良性疾病组织为7.8％ （3/38）,而正常胰腺组织未见BDNF阳性表达.正常胰腺、胰腺良性疾病、胰腺癌组织中BDNF蛋白表达量分别为0.38±0.01、0.56±0.01、0.97±0.01,mRNA表达量分别为0.85±0.14、1.67±0.21、3.45±0.67,胰腺癌和胰腺良性疾病的表达量均显著高于正常胰腺,胰腺癌又显著高于胰腺良性疾病,差异均具有统计学意义（P值均＜0.01）.BDNF阳性表达与胰腺导管腺癌的神经浸润、淋巴结转移存在相关性（P值均＜0.05）,而与患者性别、年龄及肿瘤大小、部位、分化程度等无相关性.结论 BDNF参与胰腺癌的发生、发展,并可能与胰腺癌患者预后有关.     

新生淋巴管在胰腺导管腺癌周围神经丛微转移过程中的机制研究

目的 研究新生淋巴管在胰腺导管腺癌周围神经丛微转移过程中的作用与机制.方法 收集2005年9月至2006年10月长海医院行胰腺癌扩大根治术的30例胰腺导管腺癌患者的临床资料,术中采集胰腺肿瘤、癌旁、胆管下段、胰尾、肠系膜上动脉(SMA)旁组织(含胰周神经丛)以及区域淋巴结标本.常规病理检查,采用双重免疫组化方法检测毛细淋巴管,计算淋巴管密度(LVD).结果 胰内和(或)胰周神经丛浸润25例(83.3%),其中胰内合并胰周神经丛浸润20例,单纯胰内神经浸润5例,无单纯胰周神经丛浸润病例.神经浸润与患者年龄、性别、淋巴结转移、肿瘤大小、肿瘤部位无明显相关性(P>0.05),但与JPS临床分期相关(P<0.05).癌组织内的平均LVD为每视野(4.2±3.4)个,显著少于癌旁的(11.3±6.9)个及正常胰腺组织的(10.8±4.4)个(P<0.01),正常胰腺组织与癌旁组织平均LVD值差异无统计学意义.18例胰腺癌患者在非癌组织清晰可见肿瘤浸润淋巴管,而且胰周神经丛浸润与淋巴管肿瘤浸润间亦有明显相关性(P<0.05).结论 胰腺导管腺癌周围神经丛浸润的发生率较高,神经浸润与JPS临床分期、淋巴管浸润有明显相关性,提示胰腺导管腺癌存在通过新生淋巴管途径扩散转移的可能性.     

胰腺癌组织中GABA和GAD的表达

目的研究γ-氨基丁酸(GABA)、谷氨酸脱羧酶(GAD)65和GAD67在胰腺癌组织中的表达及其意义。方法收集34例胰腺癌、12例慢性胰腺炎和10例正常胰腺组织标本,应用ABC法检测三者GABA、GAD65和GAD67的表达。结果胰腺癌GABA、GAD65和GAD67表达染色强度分值(2.41±0.49,2.09±0.29.2.10±0.30)及阳性细胞数分值(4.34±0.77,3.0±0.87,3.86±0.76)明显高于慢性胰腺炎(1.55±0.83.1.22±0.63,1.44±0.68;2.77±0.78,2.35±0.83,1.88±0.78)和正常胰腺组织(1.17±0.69,0.83±0.37,1.25±0.62;1.92±0.83,1.60±1.11,1.41±0.74),差异显著(P<0.05或P<0.01)。慢性胰腺炎GABA和GAD65的表达明显高于正常胰腺组织(P<0.05)。低分化腺癌GABA和GAD65明显高于高分化腺癌(P<0.05)。胰腺癌的GABA与GAD65表达呈正相关(r=0.67,P<0.01)。结论GABA、GAD65和GAD67的表达与胰腺癌的发生、发展及生物学行为有密切关系,可能是潜在的胰腺癌标志物之一。     

DNA甲基转移酶1和组蛋白脱乙酰基酶1在胰腺组织中的表达及其临床意义

背景：近年针对DNA甲基化和组蛋白乙酰化修饰的表观遗传学研究是探索胰腺癌发生机制的新热点。目的：研究DNA甲基转移酶1（DNMT1）和组蛋白脱乙酰基酶1（HDAC1）在胰腺上皮内瘤变（PanIN）和胰腺癌组织中的表达．探讨其可能的临床意义。方法：以免疫组化SP法检测DNMT1、HDAC1在10例正常胰腺组织、39例证实含有PanIN的胰腺癌旁组织和54例胰腺导管腺癌（PDAC）组织中的表达。结果：DNMT1和HDAC1在胰腺组织中的阳性表达率均随组织异型程度的增加而逐渐增高，即正常胰腺导管（0％）〈PanIN—IA（7．2％±1．2％，10．7％±5．0％）〈PanIN-1B（24．5％±9．6％，40．1％±8．0％）〈PanIN-2（30．0％±11．9％，51．2％±13．4％）〈PanIN-3（46．7％±11．2％，73．1％±11.3％）〈PDAC（56．7％±27．5％，82．5％±19.4％），差异均有统计学意义（P〈0．05）。结论：DNMT1和HDAC1表达增强是胰腺癌发生的早期事件．两者共同促进了胰腺癌的进展，可能成为胰腺癌早期诊疗的新靶点。     

神经生长因子及其受体在人胰腺导管癌组织中的表达

目的 探讨β神经生长因子(β-NGF)及其受体[酪氨酸激酶A(tyrosine kinase A,TrKA)和P75NGFR]在人胰腺导管癌组织中的表达及意义.方法 选择胰腺导管癌组织标本80例和正常胰腺组织20例,采用免疫组化、荧光定量PCR等方法,定量检测β-NGF及其受体表达,分析β-NGF)及其受体与临床病理学特征,尤其与神经侵袭的关系.结果 随着癌细胞分化程度降低和肿瘤TNM分期增加,β-NGF、TrKA蛋白表达水平增加,且低分化与高分化、中分化组相比显著增加(P<0.01),Ⅲ～Ⅳ期较Ⅰ～Ⅱ期显著增加(P<0.05);β-NGF、TrKA蛋白表达水平在有神经浸润组明显高于无神经浸润组(P<0.01),有淋巴结转移组明显高于无淋巴结转移组(P<0.01),且邻近神经组织的肿瘤细胞β-NGF、TrKA阳性程度高于远离神经组织的癌细胞.P75NGFR表达与肿瘤细胞分化程度关系密切.β-NGF和TrKA表达呈正相关.β-NGF、TrKA和P75NGFR mRNA表达水平在胰腺癌组织中明显高于正常胰腺组织,分别增加3.84、4.23和2.41倍.结论 β-NGF及其受体参与介导胰腺癌的发生,与胰腺癌临床病理学特征关系密切,β-NGF、TrKA高表达和胰腺癌嗜神经性关系密切.     

E-钙黏附素和β-连环素在胰腺上皮内瘤变和胰腺癌组织中的表达

目的:探讨胰腺上皮内瘤变PanIN和胰腺癌组织中E-钙黏附素(E-Cad)和β-连环素(β-Cat)异常表达的意义.方法:回顾性研究长海医院2001-01/2003-12间外科切除和同期尸检的156例胰腺标本,并构建了组织芯片,其中含有129灶PanIN-1A,104灶PanIN-1B,22灶PanIN-2,11灶PanIN-3和121例导管腺癌和相应癌旁组织.用EnVision免疫组化技术检测上述病变组织中E-Cad和β-Cat的表达变化,并结合临床病理资料进行相关分析.结果:导管腺癌中E-Cad异常表达率明显高于PanINs和正常导管(64.5%,32.3%,0%),且与胰腺癌的分化程度、淋巴结转移和神经浸润密切相关(P＜0.05).PanINs和导管腺癌中E-Cad胞质表达较正常导管明显增加.β-Cat的异常表达与胰腺癌淋巴结转移和神经浸润有明显相关性(P＜0.05).高级别PanINs和导管腺癌中β-Cat胞质和胞核的表达率明显高于低级别PanINs和正常导管(P＜0.05).PanINs和导管腺癌中E-Cad和β-Cat表达间呈正相关性(P＜0.01,P＜0.05).结论:胰腺癌和PanINs中E-Cad和β-Cat的异常改变提示他们不仅与胰腺癌的生物学行为和预后有关,而且也参与了胰腺癌的发生.     

胰腺癌组织中GABA和GAD的表达

目的 研究γ-氨基丁酸(GABA)、谷氨酸脱羧酶(GAD)65和GAD67在胰腺癌组织中的表达及基意义.方法 收集34例胰腺癌、12例慢性胰腺炎和10例正常胰腺组织标本,应用ABC 法检测三者GABA、GAD65和GAD67的表达.结果 胰腺癌GABA、GAD65和GAD67表达染色强度分值(2.41±0.49,2.09±0.29,2.10±0.30)及阳性细胞数分值(4.34±0.77,3.0±0.87,3.86±0.76)明显高于慢性胰腺炎(1.55±0.83,1.22±0.63,1.44±0.68;2.77±0.78,2.35±0.83,1.88±0.78)和正常胰腺组织(1.17±0.69,0.83±0.37,1.25±0.62;1.92±0.83),1.60±1.11,1.41±0.74),差异显著(P＜0.05或P＜0.01).慢性胰腺炎GABA和GAD65的表达明显高于正常胰腺组织(P＜0.05).低分化腺癌GABA和GAD65明显高于高分化腺癌(P＜0.05).胰腺癌的GABA与GAD65表达呈正相关(r=0.67,P＜0.01).结论 GABA、GAD65T和GAD67的表达与胰腺癌的发生、发展及生物学行为有密切关系,可能是潜在的胰腺炎标志物之一.     

Relationship between K-ras mutation and the expression of p21WAF1/CIP1 and p53 in chronic pancreatitis and pancreatic adenocarcinoma

Overexpression of p21WAF1/CIP1 was recently described as an early event in the development of pancreatic intraepithelial neoplasia. Since activating K-ras mutations are described in more than 80% of pancreatic cancers and are known to increase intracellular levels of p21WAF1/CIP1 in experimental models, the possible role of activating K-ras mutations in an induction of the p21WAF1/CIP1 expression was investigated in our study. We examined 71 surgical specimens, 29 of chronic pancreatitis and 42 of invasive ductal adenocarcinoma both having a large spectrum of PanIN (pancreatic intraepithelial neoplasia) lesions. Expression of p53 and p21WAF1/CIP1 was examined immunohistochemically and codon 12 K-ras mutational analysis was performed using the very sensitive mutant-enriched PCR-RFLP (polymerase chain reaction-restriction fragment length polymorphism) analysis. Our study demonstrated the overexpression of p21WAF1/CIP1 as an early event in the development of pancreatic intraepithelial neoplasia in the group of chronic pancreatitis and invasive adenocarcinoma as well. Overexpression of p21WAF1/CIP1 increased progressively from normal ducts through the spectrum of PanIN lesions to invasive carcinomas. The p53 overexpression increased again progressively according to the severity of the lesion and seems to be a later event in the development of pancreatic intraepithelial neoplasia if compared to p21WAF1/CIP1 expression. Our results confirmed also the possible p53 independent p21WAF1/CIP1 expression in some PanIN2, PanIN3 lesions and invasive carcinomas. K-ras mutations were not revealed in samples with only low grade PanIN lesions (PanIN1a and PanIN1b). K-ras mutations were detected in 69,4% adenocarcinomas and in only one case of chronic pancreatitis. Two codon 12 K-ras positive pancreatic carcinomas showed K-ras mutations in the surrounding normal pancreatic tissue. In adenocarcinomas, no statistically significant correlation was found between K-ras mutational status and p21WAF1/CIP1 and p53 expression, respectively. The possible role of activating K-ras mutations in an induction of p21WAF1/CIP1 expression was not confirmed in this study.     

Cyclooxygenase-2 expression associated with severity of PanIN lesions: a possible link between chronic pancreatitis and pancreatic cancer.

BACKGROUND: Cyclooxygenase-2 (COX-2) is a key modulatory molecule in inflammation and neoplasia. Increasing evidence suggests a role for COX-2 in pancreatic cancer (PAC). However, expression of COX-2 in pancreatic intraepithelial neoplasia (PanIN), the precursor lesion of PAC which is often present in chronic pancreatitis (CP), has received little attention. METHOD: COX-2 immunostaining was performed on sections of PAC (n = 26), CP (n = 34), PanIN (n = 68) and normal pancreas (n = 11). Sections were also stained for macrophages (CD68), activated pancreatic stellate cells (alphaSMA), and collagen (Sirius Red) as markers of fibrosis.Semiquantitative scoring was based on the extent and intensity of immunostaining. RESULTS: COX-2 expression was increased in PAC compared to normal (p = 0.02) with 89% of cases exceeding COX-2 immunostaining in normal ducts. In PanIN lesions, COX-2 expression increased with escalating severity of the PanIN change (p < or = 0.01). COX-2 expression was increased in PanIN-2/3 compared to normal pancreas and CP (p < or = 0.001). In ducts of CP, COX-2 expression did not differ from that in normal tissue. There was no association between COX-2 expression and clinicopathological variables. CONCLUSION: The high level of COX-2 expression in PanIN lesions suggests that this enzyme could be a therapeutic target at a non-invasive stage of pancreatic carcinogenesis and feasible for chemoprevention in CP.     

Serine protease inhibitor Kazal type 1 and epidermal growth factor receptor are expressed in pancreatic tubular adenocarcinoma, intraductal papillary mucinous neoplasm, and pancreatic intraepithelial neoplasia

Background

Serine protease inhibitor Kazal type 1 (SPINK1) is expressed in normal human pancreatic acinar cells and in a variety of tumors, and binds to the epidermal growth factor receptor (EGFR), mediating cell proliferation through the mitogen-activated protein kinase cascade in pancreatic cancer cell lines. Here, we aimed to assess SPINK1 and EGFR expression in various neoplastic lesions, including tissues demonstrating precancerous changes.

Methods

Surgical specimens of pancreatic ductal adenocarcinoma (n = 23), intraductal papillary mucinous neoplasm (IPMN; n = 21), pancreatic neoplasms other than ductal adenocarcinoma (n = 8), chronic pancreatitis (n = 11), and pancreatic intraepithelial neoplasia (PanIN) lesions within the resected specimens were analyzed immunohistochemically for SPINK1 and EGFR expression.

Results

Sixty-five PanIN-1A, 32 PanIN-1B, 17 PanIN-2, and 6 PanIN-3 were identified. Both SPINK1 and EGFR were expressed in almost all PanIN lesions. All tubular ductal adenocarcinoma, IPMN, and mucinous cystadenocarcinoma samples (neoplasms of ductal origin) expressed SPINK1, whereas acinar cell carcinoma, anaplastic carcinoma, adenosquamous carcinoma, insulinoma, and islet cell carcinoma did not. EGFR was expressed in 87 % of tubular adenocarcinoma and 48 % of IPMN lesions. Among IPMN lesions, malignant lesions (IPMC) expressed EGFR more often than benign lesions (IPMA) did. Scattered expression of EGFR was observed in normal pancreatic ducts and within the tubular complex within chronic pancreatitis lesions.

Conclusions

These results indicate that SPINK1 plays a role as a growth factor, signaling through the EGFR pathway in pancreatic ductal adenocarcinoma and neoplasms, and that the EGFR is involved in the malignant transformation of IPMN.     

Current understanding of precursors to pancreatic cancer

Precursors to pancreatic cancer have been investigated for a century. Previous studies have revealed three distinct precursors,i.e. mucinous cystic neoplasm (MCN), intraductal papillary mucinous neoplasm (IPMN), and pancreatic intraepithelial neoplasia (PanIN), harboring identical or similar genetic alterations as does invasive pancreatic carcinoma. The current understanding of precursors to pancreatic cancer can be illustrated by progressive pathways from noninvasive MCN, IPMN, and PanIN toward invasive carcinoma. MCNs consist of ovarian‐type stroma and epithelial lining with varying grades of atypia, and are occasionally associated with invasive adenocarcinoma. The epithelium of noninvasive IPMNs shows a variety of different directions of differentiation, including gastric, intestinal, pancreatobiliary (PB), and oncocytic types. IPMNs can also harbor varying grades of architectural and cytologic atypia. IPMNs confined to branch ducts are mostly the gastric type, and IPMNs involving the main ducts are often intestinal type, while PB and oncocytic types are rare. Small (<1 cm) IPMNs of the gastric type are not always morphologically distinguishable from low‐grade PanINs. Mucin expression profiles suggest intestinal‐type IPMNs progress to mucinous noncystic (colloid) carcinoma, while PB‐type IPMNs progress toward ductal adenocarcinoma. It is a well‐described paradigm that PanIN lesions progress toward ductal adenocarcinoma through step‐wise genetic alterations. The activation of Hedgehog and Notch signaling pathways in PanIN lesions as well as in pancreatic adenocarcinoma suggest that developmental pathways may be disregulated during carcinogenesis of the pancreas. Further study is needed to elucidate the pathways from precursors toward invasive carcinoma of the pancreas.     

Overexpression of pancreatitis-associated protein (PAP) in human pancreatic ductal adenocarcinoma

Pancreatitis-associated protein (PAP) is almost absent in normal pancreas, but is strongly induced in acute pancreatitis. PAP mRNA is also expressed in cancer cells, including pancreatic ductal adenocarcinoma. However, the clinicopathological significance of PAP in human pancreatic cancer is not clear. We examined PAP expression in pancreatic tissues from individuals with pancreatic ductal adenocarcinoma using immunohistochemistry. PAP was overexpressed in 79% (30 of 38) of pancreatic ductal adenocarcinoma, 19% (7 of 36) of chronic pancreatitis, and 29% (2 of 7) of mucinous cystadenoma. PAP was found in malignant ductular structures in pancreatic carcinomas as well as in benign proliferating ductules and acinar cells in chronic pancreatitis. It was not expressed in normal pancreas. The incidence of PAP overexpression was significantly higher in pancreatic cancer than in the other pancreatic diseases (P < 0.01). PAP overexpression was significantly correlated with nodal involvement, distant metastasis (P < 0.05), and short survival (P < 0.01) in pancreatic cancer. These results suggest that overexpression of PAP in human pancreatic ductal adenocarcinoma indicates tumor aggressiveness.     

Precancerous conditions of pancreatic carcinoma

The precancerous conditions associated with pancreatic ductal carcinoma include preneoplastic duct changes and benign-looking tumors that give rise to ductal carcinomas. Among the duct changes that are discussed as precancerous lesions are hyperplastic and metaplastic lesions, which were recently classified as pancreatic intraepithelial neoplasia types 1A, 1B, 2, and 3. This new system is compared with the older terminology. Recent molecular findings concerning the most frequent genetic alterations in manifest carcinomas support the new classification system. The relative frequency of duct lesions in the nonneoplastic pancreas and their association with chronic pancreatitis and ductal carcinoma are discussed. Finally, the pancreatic exocrine tumors that may give rise to ductal carcinomas are presented.     

In vivo diagnosis of murine pancreatic intraepithelial neoplasia and early-stage pancreatic cancer by molecular imaging

Pancreatic ductal adenocarcinoma (PDAC) is a fatal disease with poor patient outcome often resulting from late diagnosis in advanced stages. To date methods to diagnose early-stage PDAC are limited and in vivo detection of pancreatic intraepithelial neoplasia (PanIN), a preinvasive precursor of PDAC, is impossible. Using a cathepsin-activatable near-infrared probe in combination with flexible confocal fluorescence lasermicroscopy (CFL) in a genetically defined mouse model of PDAC we were able to detect and grade murine PanIN lesions in real time in vivo. Our diagnostic approach is highly sensitive and specific and proved superior to clinically established fluorescein-enhanced imaging. Translation of this endoscopic technique into the clinic should tremendously improve detection of pancreatic neoplasia, thus reforming management of patients at risk for PDAC.