Expression of transforming growth factor alpha and epidermal growth factor receptor in human hepatocellular carcinoma

Abstract: Transforming growth factor alpha (TGF-alpha) is thought to be involved in liver regeneration, cellular proliferation, and hepatocarcinog-enesis. We have looked at the relationship between TGF-alpha and it's receptor, and have attempted to relate the expression of TGF-alpha and it's receptor to the differentiation of hepatocellular carcinoma (HCC) on serial sections of HCC. We examined immunohistochemically the expression of the TGF-alpha and of epidermal growth factor receptor (EGFR) proteins in the same area of 53 nodules (<5 cm in diameter) of HCC obtained from patients. Immnnoreactive proteins were visualized by using a biotin-streptoavidin system (LSAB Kit, Dako). TGF-alpha was strongly expressed in 29 of 53 (54.7%) nodules. Specimens strongly positive for TGF-alpha were found mainly in well-differentiated HCC, while specimens positive for EGFR were found mainly in poorly differentiated HCC (p<0.05). In the tissues that stained weakly positive for TGF-alpha, the expression of EGFR differed significantly, according to the degree of HCC histologic differentiation (p<0.05). These results led us to speculate that the expression of TGF-alpha and EGFR might be related to the pattern of histologic differentiation of HCC.     

Expression of Rab5a in hepatocellular carcinoma: Possible involvement in epidermal growth factor signaling

Aim: The Rab subfamily plays a role in intracellular transport. Rab5a is, in particular, involved in receptor-mediated endocytosis. Epidermal growth factor (EGF) is known to induce cell migration and promote invasion and angiogenesis. The EGF receptor (EGFR) is actively internalized upon the addition of EGF. The aim of the present study was to clarify the expression of Rab5a in hepatocellular carcinomas (HCC) and to examine its effect on EGF signaling. Methods: The expression of the Rab5a protein in HCC and corresponding non-tumorous tissues from 23 patients with HCC who had undergone surgical resection were analyzed by immunoblotting. A stable transfectant of Rab5a dominant negative (S34N) was established in a human hepatoma cell line, PLC/PRF/5 (PLC/PRF/5/Rab5aDN). Results: High expression (tumor/non-tumor (T/N) ratios >/= 1) of Rab5a protein in HCC compared to the paired non-tumortissues was recognized in 15 patients (65.2%) of 23 samples. The Rab5a antigen was diffusely expressed in the cytoplasm and membranes of the cancer cells. The membrane-associated Rab5a is also enhanced via overexpression in HCC. The EGF-induced endocytosis of EGFR and the phosphorylation of MAP kinase were inhibited in PLC/PRF/5/Rab5aDN cells. The migration of PLC/PRF/5/Rab5aDN cells induced by EGF was also significantly attenuated. Conclusions: These results indicate that the overexpression of Rab5a in HCC may play an important role in EGF signaling.     

Expression of transforming growth factor alpha in human hepatocellular carcinoma

ABSTRACT— Transforming growth factor alpha (TGF-α) is a mitogenic polypeptide which acts on the epidermal growth factor receptor (EGFR). The aim of this study was to examine the expression of TGF-α in human hepatocellular carcinoma (HCC) and surrounding cirrhotic tissue, and to compare it with normal liver. Immunoreactive TGF-α was detected using two antibodies raised against its C terminus, a polyclonal antibody 26T and a monoclonal antibody Ab-2. In normal liver immunoreactive TGF-α was localised strongly to bile duct epithelium and weakly in occasional parenchymal cells but was notably absent from perisinusoidal and Kupffer cells. Eight out of twenty-eight (28%) cases of HCC expressed TGF-α as demonstrated by cytoplasmic staining with both antibodies and in four cases additional membrane immunoreactivity was demonstrated using 26T. However, where cirrhotic tissue surrounding TGF-α positive tumours was available for analysis immunoreactive TGF-α was detected in only 1/7 cases. TGF-α synthesis by malignant hepatocytes was supported by the detection of specific RNA by Northern blotting from two cases with TGF-α immunoreactivity. These results implicate bile duct epithelium as an important source of TGF-α in human liver. Furthermore, in HCC the expression of TGF-α in some cases, together with paucity of TGF-α immunoreactivity in surrounding cirrhotic tissue, suggests that TGF-α may play a role in continued cell proliferation in human hepatocarcinogenesis.     

Expression of epidermal growth factor and fibroblast growth factor in human hepatocellular carcinoma: an immunohistochemical study.

Expression of epidermal growth factor (EGF) and fibroblast growth factor (FGF) was examined in 56 patients with hepatocellular carcinoma (HCC) using an immunohistochemical method. EGF and FGF were expressed on carcinoma cells in 14 (25%) and 23 cases (41%), respectively. In the 23 FGF-positive cases, 11 cases were positive for both acidic and basic FGF, while 18 were positive for acidic FGF, and 16 were positive for basic FGF. In non-cancerous hepatic tissues, FGF was weakly positive in macrophages, hepatocytes and vascular endothelial cells in some cases, while EGF was totally negative. There were no significant correlations between the expression of EGF or FGF on carcinoma cells and the various clinicopathologic factors examined. These data suggest that EGF and FGF are produced by human HCC cells in vivo. The roles of the expression of these growth factors in the development and progression of HCC remain only speculative.     

Over-expression of fibroblast growth factor receptor 3 in human hepatocellular carcinoma

AIM:To describe the significant over-expression of fibroblast growth factor receptor 3 (FGFR3), which is a signal transduction and cell proliferation related gene in hepatocellular carcinoma (HCC). METHODS:Following DNA microarray, Northern blot and quantitative real-time PCR were employed to confirm FGFR3 expression difference in HCC tissues and surrounding non-neoplastic liver tissue. FGFR3 expression levels were further determined by immunohistochemical study in 43 cases of HCC. RESULTS:Northern blot results showed the significant over-expression of FGFR3 in HCC tissues, which was consistent with that from DNA microarray. Quantitative real-time PCR demonstrated that the mean ratio of FGFR3 mRNA to glyceraldehyde-3-phosphate dehydrogenase (GADPH) mRNA in HCC tissue was 0.250, whereas the ratio in non-neoplastic liver tissue was 0.014. Statistical analyses of 43 cases of HCC revealed that HCC scored higher than the matched non-neoplastic liver tissues. Examination of clinicopathological features revealed a strong correlation of over-expression of FGFR3 with poor tumor differentiation and high nuclear grade. CONCLUSION:Over-expression of FGFR3 may play an important role in liver carcinogenesis. FGFR3 may be an ideal candidate as a molecular marker in the diagnosis of HCC and a potential therapeutic target.     

碱性成纤维细胞生长因子在肝细胞癌中的表达及意义

目的 探讨bFGF在肝细胞癌中的表达及其临床病理意义。方法 使用免疫组化SABC法检测41例肝细胞癌手术切除标本及5例外伤性肝破裂肝切取标本。结果 正常对照组bFGF均为阴性。肝细胞癌组bFGF阳性率为70．7％（29／41）。bFGF表达与患者年龄、性别、AFP是否阳性、HBsAg是否阳性无关（P＞0．05）；而与肝癌分化程度、有无癌栓、包膜是否完整有关。在高侵袭转移组与低侵袭转移组间，bFGF阳性率分别为86．4％和52．6％，差异具有显著性（P＜0．05）。结论 bFGF在肝细胞癌中高表达，可以作为判断肝癌恶性程度及转移潜能的参考指标。     

EGF受体和转化生长因子α mRNA在人大肠癌组织的表达意义

目的研究表皮生长因子受体（ＥＧＦＲ）及转化生长因子α（ＴＧＦα）在人大肠癌三组不同组织中的表达，探讨其在大肠癌发生发展中的作用．方法分别取１４例大肠癌患者癌瘤组织、癌旁２ｃｍ及１０ｃｍ之全层肠管，采用Ｎｏｒｔｈｅｒｎｂｌｏｔ方法分别检测ＥＧＦＲ和ＴＧＦαｍＲＮＡ表达．结果大肠癌三组１４例不同组织中均有ＥＧＦＲ和ＴＧＦαｍＲＮＡ不同程度表达，以癌旁组织中表达为最强，同一病例比较，癌远侧组织中表达呈减弱趋势．癌远侧组织中，３例Ａ，Ｂ两期杂交信号明显弱于其他例Ｃ，Ｄ期信号．结论ＥＧＦＲ，ＴＧＦα在大肠癌发生发展中起重要作用，其ｍＲＮＡ表达与Ｄｕｋｅｓ分期相关，可望作为大肠癌恶性程度的指标．其在癌远侧组织中表达减弱的趋势提示是否可作为肿瘤手术切缘的评估指标，尚有待进一步的研究．     

胃癌组织与血清中VEGF和bFGF的表达意义

目的：研究胃癌患者血清和组织中VEGF,bFGF的表达与胃癌临床特征之间的关系,研究二者的相关性及组织和血清之间的相关性,探讨VEGF,bFGF在胃癌的发生、发展、侵袭和转移中的作用方法：应用酶联免疫技术(ABC-ELISA方法)检测73例胃癌患者术前血清和20例健康体检者血清中的VEGF,bFGF的表达水平,同时应用免疫组织化学染色方法检测癌组织和癌旁组织中VEGF,bFGF的表达．结果：胃癌患者术前血清VEGF,bFGF表达水平均明显高于健康体检者(YEGF：101．8±53．3 ng/L vs 16．1±22．5ng/L,P＜0．05；bFGF：152．9±42．7ng/L vs 25．0±11．4ng/L,P＜0．05)．胃癌患者术前血清VEGF,bFGF的表达水平均随胃癌的浸润深度、TNM分期、淋巴结转移、远处转移而增高(P＜0．05),而与年龄、性别及病理类型无关．胃癌组织VEGF的阳性表达率为71．2%,癌旁组织中VEGF均未见阳性表达,二者之间有显著性差异(X~2=32．1,P＜0．05)；胃癌组织中bFGF的阳性表达率为63．0%、癌旁组织中bFGF阳性表达率为(10%),二者之间亦有显著性差异(X~2=17．7,P＜0．05)．胃癌患者组织VEGF,bFGF的表达水平均与胃癌的浸润深度、TNM分期、淋巴结转移、远处转移有关(P＜0．05),而与年龄、性别及病理类型无关．胃癌患者血清VEGF的表达水平与血清bFGF的表达水平呈明显正相关(r=0．439,P＜0．01),胃癌患者组织VEGF的表达水平与组织bFGF的表达水平呈明显正相关(r=0．391,P＜0．01)；胃癌患者术前血清VEGF的表达水平与组织VEGF的表达呈正相关(r=0．346,P＜0．01),术前血清bFGF的表达水平与组织bFGF的表达呈正相关(r=0．304,P＜0．01),均有显著性差异．结论：VEGF,bFGF在胃癌的发生、发展、转移及预后起着重要的作用,有望成为胃癌术前诊断、术后随访、复发转移监测、评价抗血管生成药物疗效和化疗效果判定的新的肿瘤标志物．     

大肠癌和大肠腺瘤COX-2和BFGF表达的意义

目的:研究COX-2和BFGF在大肠癌及大肠腺瘤组织中的表达及意义．方法:采用免疫组化SP方法检测了手术切除的大肠癌49例,腺瘤性息肉25例,正常大肠黏膜组织20例中的COX-2和BFGF表达．结果:COX-2和BFGF在大肠癌中的表达阳性率分别为59．2％和69．3％,在腺瘤性息肉的表达率为52．0％和56．0％,COX-2和BFGF在大肠癌组织与腺瘤性息肉中表达无显著性差异(P>0．05):正常肠黏膜中未检出COX-2和BFGF．COX-2和BFGF在大肠癌中表达与性别,年龄,肿瘤大小,肿瘤位置,分化程度无关(P>0．05)．但与肿瘤Dukes分期有关,C,D期高于A,B期(81．5％vs 54．5％,P<0．05),淋巴结转移之间具有显著性差,有异淋巴结转移高于无淋巴结转移(81．5％vs 54．5％,P<0．05)．肠癌组织中COX-2、BFGF表达二者间有相关性(r= 0．349,P<0．05)．结论:COX-2、BFGF在大肠癌组织及大肠腺瘤中的表达水平增高,在大肠腺瘤恶变及大肠癌的发生发展过程中起协同作用,共同促进肿瘤的发生．     

肝细胞肝癌中血管内皮生长因子与浸润树突状细胞表达的相关性研究

研究肝细胞癌(HCC)中血管内皮生长因子(VEGF)的表达与浸润性树突状细胞(DC)的相关性。用免疫 组织化学方法研究45例HCC组织标本VEGF的表达及s-100阳性标记的DC数量,并探讨两者的相关性。在HCC 中VEGF的阳性表达和s-100蛋白阳性表达率分别为62．2％(28／45)和46．7％(21／45),VEGF及DC均与肝癌的转 移有关(P均<0．05);VEGF的阳性表达与DC的浸润程度呈负相关(P<0．05)。HCC组织中VEGF的表达与DC的 浸润程度呈负相关,两者在肝癌发生发展中均起重要作用。     

卵巢肿瘤组织中EGFR、CK20表达及意义

目的探讨细胞角质蛋白20（CK20）和表皮生长因子受体（EGFR）mRNA在卵巢上皮性肿瘤发生中的作用。方法应用RT-PCR法检测12份正常卵巢（对照组）、18份卵巢良性肿瘤（良性组）、33份卵巢恶性肿瘤（恶性组）和14份胃肠道转移性卵巢肿瘤（转移组）组织中CK20、EGFR mRNA的表达。结果恶性组中CK20、EGFR mRNA阳性率显著高于对照组及良性组（P〈0.05）,与转移组比较无明显差异;恶性组CK20 mRNA表达与手术病理分期、淋巴结转移有关（P〈0.05）,EGFR mRNA表达与手术病理分期有关（P〈0.05）。结论CK20、EG-FR高表达可促进卵巢恶性肿瘤的发生、转移;其检测对判断预后有一定价值。     

Cimetidine inhibits epidermal growth factor-induced cell signaling

BACKGROUND: Cimetidine, a histamine-2 (H2) receptor antagonist, has been demonstrated to have anticancer effects on colorectal cancer, melanoma and renal cell carcinoma. In the current study, we clarified that cimetidine inhibits both epidermal growth factor (EGF)-induced cell proliferation and migration in hepatocellular carcinoma (HCC) cell lines. METHOD: HCC cell lines (Hep3B, HLF, SK-Hep-1, JHH-2, PLC/PRF/5 and HLE) were used and cell proliferation was assessed by [3H]-thymidine incorporation assay. Cell migration was measured by in vitro cell migration assay. Biological effects of cimetidine were assessed with human EGF receptor (EGFR)-expressing mouse fibroblast cells (NR6-WT). The autophosphorylation of EGFR and the activation of other downstream effectors were analyzed by immunoprecipitation and immunoblotting. The concentration of intracellular cyclic AMP (cAMP) was measured by competitive enzyme immunoassay. RESULTS: Cimetidine inhibited both EGF-induced cell proliferation and migration in Hep3B, HLF, SK-Hep-1 and JHH-2, while cimetidine did not affect EGF-induced cell proliferation and migration in PLC/PRF/5 and HLE. Cimetidine was revealed to disrupt the EGF-induced autophosphorylation of EGFR and its downstream effectors, mitogen activated protein kinases and phospholipase C-gamma. To define the molecular basis of this negative regulation, we identified that cimetidine significantly decreased intracellular cAMP levels and that decrement of cAMP inhibited autophosphorylation of EGFR. The cell permeable cAMP analog, CPT-cAMPS reversed the cimetidine-induced inhibition of EGF-induced cell proliferation and cell migration by restoring autophosphorylation of EGFR. CONCLUSION: Cimetidine inhibited EGF-induced cell proliferation and migration in HCC cell lines by decreasing the concentration of intracellular cAMP levels. Cimetidine may be a candidate chemopreventive agent for HCC.     

Quantitative analysis using ELISA of vascular endothelial growth factor and basic fibroblast growth factor in human colorectal cancer, liver metastasis of colorectal cancer and hepatocellular carcinoma

TO THE EDITOR Angiogenesis consists of the sprouting of capillaries from pre-existing vessels[1]. It is well-known that tumor growth is angiogenesis-dependent. Vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF)stimulated vascular endothelial cell proliferation and are involved in the neoplastic angiogenesis of several types of tumors including those of the intestinal tract[1-5].     

甲状腺增殖性疾患组织表皮生长因子及其受体的表达

目的　探讨表皮生长因子 (EGF)及其受体 (EGFR)在甲状腺增殖性疾患中的表达及其作用。方法　应用免疫组化ABC染色方法观察 70例甲状腺组织切片EGF及EGFR的表达。结果(1)EGF在正常、肿瘤及非肿瘤组织中几乎均无表达。 (2 )乳头状、滤泡型甲状腺癌及其混合癌EGFR阳性表达高于非癌疾患及正常组织 (P <0 .0 5 ) ,阳性表达程度以强阳性为主。 (3)在正常组织、良性腺瘤、结节性甲状腺肿及桥本病 ,弱或中度的EGFR阳性表达率各组间差异无显著性。正常组织阳性表达率虽高达 83.3 % ,但 2 / 3表达为弱阳性。 (4 )乳头状甲状腺癌以细胞浆表达EGFR占优势 ,滤泡型及混合型甲状腺癌主要为混合着色 ,但与非癌混合着色不同的是多数以胞浆表达占优势 ;良性疾患以混合染色为主 ,但结节性甲状腺肿以膜着色居多。正常组织为浆、膜混合着色。结论　 (1)对EGFR强阳性表达尤其细胞浆为主者应高度疑及甲状腺癌。 (2 )各甲状腺良性疾患均有不同程度EGFR表达 ,虽无统计学意义上的差别 ,却可说明EGFR对于良性肿瘤及非肿瘤增殖性疾患的生成均有不应忽视的作用。