Expression of the Met/HGF receptor in normal and neoplastic human tissues.

The MET oncogene encodes a transmembrane tyrosine kinase receptor. Recently, hepatocyte growth factor (HGF), a potent growth factor for hepatocytes involved in liver regeneration, has been proposed as a ligand. In this paper, the physiological role of the human Met/HGF receptor is investigated by studying its specific distribution in normal and neoplastic tissues. Northern blot analysis has shown that the MET gene is selectively expressed in several epithelial tissues. High levels of MET mRNA have been found in liver, gastrointestinal tract, thyroid and kidney. Western blot analysis has shown that the levels of the Met protein generally correspond to those of the mRNA. However, in the thyroid, where there is a high level of MET mRNA, the protein was barely detectable, suggesting translational or post-translational regulation. The protein was also detected in the brain. Normal or increased levels of MET mRNA and Met protein were consistently found in fresh samples of carcinomas as well as in epithelial tumor cell lines. In thyroid carcinomas of a specific histiotype the amount of Met protein, almost undetectable in the normal counterpart, was found to be increased more than 100-fold. The tissue distribution of the Met/HGF receptor indicates that this molecule is involved in growth control of epithelial cells other than hepatocytes and suggests that its increased expression may confer a growth advantage to neoplastic cells.     

Gene expression profiling of colorectal adenomas and early invasive carcinomas by cDNA array analysis

It is generally accepted that most colorectal carcinomas arise in pre-existing adenomas. Morphologically, colorectal adenomas can be divided into two groups, protruded type and flat type. The aim of this study was to clarify relevant alterations of gene expression associated with the early stage of colorectal carcinogenesis. Using cDNA array, we analysed the expression profiles of 550 cancer-related genes in 36 colorectal adenomas (18 flat-type and 18 protruded-type adenomas) and 14 early invasive carcinomas. Among the 550 genes, we chose 32 genes the average expression levels of which were at least three-fold up- or downregulated in tumour tissues compared with levels in matched normal tissues. A total of 13 and 19 genes were identified as up- and downregulated genes in tumour tissues, respectively. Among the upregulated genes, the average expression levels of E1AF, bone morphogenic protein (BMP)-4, insulin-like growth factor (IGF)-2, inducible nitric oxide synthase (iNOS), tissue inhibitors of metalloproteinase (TIMP)-1, Smad4, and nm23 in tumour tissues were over five times higher than those in matched normal tissues. Colorectal adenomas and early invasive carcinomas were divided into two major clusters by clustering analysis. Moreover, flat- and protruded-type adenomas were divided into two major clusters by clustering analysis. The expression profiles obtained by the cDNA array clearly indicate that colorectal adenomas and early invasive carcinomas have specific expression profiles. Likewise, the gene expression profiles of flat- and protruded-type adenomas are different. These results indicate that molecular classification of early colorectal tumours by a cDNA array is feasible.     

Activation of hepatocyte growth factor/scatter factor in colorectal carcinoma

Activation of hepatocyte growth factor/scatter factor (HGF/SF) in the extracellular milieu is a critical limiting step in the HGF/SF-induced signaling pathway mediated by Met receptor tyrosine kinase, which has potentially important roles in tumor biology and progression. However, little is known concerning the regulation of HGF/SF activation in tumors. Immunoblot analysis revealed that the activation of HGF/SF was enhanced significantly in colorectal carcinoma tissues compared with the corresponding normal mucosa. Serum-free conditioned media of cultured human colorectal carcinoma cell lines contained HGF/SF-activating activity, and the addition of a single-chain precursor form of HGF/SF to the serum-free culture of these cells resulted in HGF/SF-dependent modulation of cellular phenotypes, such as increased scattering and enhanced secretion of vascular endothelial growth factor. This processing activity was enhanced by thrombin treatment but was inhibited significantly by a neutralizing antibody against HGF activator (HGFA), a factor XIIa-like serine proteinase believed to be expressed mainly in the liver. The activity was also inhibited by recombinant HGFA inhibitor type 1 (HAI-1). The presence of HGFA mRNA and secretion of HGFA protein were confirmed in the cell lines. Therefore, extrahepatic expression of HGFA in the colorectal carcinoma cells could be responsible for the single-chain HGF/SF-processing activity of the cells. We examined the expression of HGFA and HAI-1 in human colorectal mucosa and adenoma-carcinoma sequence. Immunohistochemically, HGFA was stained weakly in the normal enterocytes, and immunoreactivity was increased modestly in the neoplastic differentiation. The subcellular localization of HGFA immunoreactivity was altered in carcinoma cells showing basal or cell-stroma interface staining patterns, compared with normal and adenoma cells with a supranuclear or apical staining pattern. In contrast to HGFA, the expression of HAI-1 decreased significantly in carcinoma cells relative to the adjacent normal or adenoma cells, indicating that the net balance between HGFA and HAI-1 shifts in favor of HGFA in carcinomas. In fact, pro-HGFA and the active form of HGFA proteins increased in carcinoma tissue compared with the corresponding normal mucosa. It was concluded that HGFA is expressed in colorectal mucosa and tumors and could be involved in the activation of HGF/SF in colorectal carcinomas. Therefore, the balance between HGFA and HAI-1 could play an important role in the regulation of HGF/SF activity in colorectal carcinomas.     

散发性结直肠癌组织中FHIT、MSH2蛋白的异常表达及其临床意义

背景与目的:脆性组氨酸三联体(fragilehistidinetriad,FHIT)蛋白表达缺失是胃肠道肿瘤的频发事件,但在大肠癌却有争议;最近研究表明FHIT蛋白表达失活可能是错配修复蛋白,尤其是mutS同种组织蛋白2(mutShomolog2,MSH2)改变的结果。本研究旨在探讨FHIT、MSH2蛋白在散发性结直肠癌(sporadiccolorectalcarcinoma,SCC)组织中的表达情况及其临床意义。方法:采用免疫组化SP法检测手术切除的84例SCC及其对应癌旁正常结直肠组织和23例肠腺瘤组织标本中FHIT、MSH2蛋白的表达。结果:FHIT蛋白在SCC组织、结直肠腺瘤组织、癌旁正常结直肠组织中阳性率分别为48.81%、73.91%和100%,三者的阳性率差异有显著性(P<0.05)。FHIT蛋白表达水平与SCC患者的年龄、性别及肿瘤部位、组织学类型无关(P>0.05),而与肿瘤浸润深度、分化程度、Dukes分期和淋巴结转移有关(P<0.05),在浸润深度越深、分化程度越低、Dukes分期越晚和有淋巴结转移的癌组织中,FHIT蛋白低表达就越明显;而MSH2蛋白表达水平仅与Dukes分期有关(P<0.05)。SCC中FHIT蛋白表达与MSH2蛋白表达呈正相关(r=0.3728,P<0.01)。结论:(1)FHIT蛋白表达水平与SCC的恶性程度有关,可作为预测SCC浸润转移潜能的一项有意义的生物学指标;(2)SCC中FHIT、MSH2蛋白表达二者之间呈正相关。     

Expression of Bcl-2 and c-ErbB-2 in colorectal neoplasia

Several studies have been demonstrated the value of c-ErbB-2 and Bcl-2 in predicting the biological behaviour of tumors. The aim of this study was to investigate Bcl-2 and c-ErbB-2 expression in colorectal carcinomas and the correlation between their presence and other clinicopathologic parameters. Eighty-six colorectal carcinomas and 17 adenomas were stained with Bcl-2 and c-ErbB-2 immunohistochemically. Staining patterns were assessed semi-quantitatively and correlated with tumor size, Duke s classification, tumor differentiation, mucinous characteristic and anatomic locations. We detected Bcl-2 expression in 10 of 17 adenomas (58.8 %) and 31 of 86 carcinomas (36.04 %). Positive staining in normal mucosa was observed only in the compartment of cryptic cells. However neither the difference in the rates of Bcl-2 positivity in adenoma and carcinoma groups, nor the correlation with other mentioned clinicopathological parameters, were found statistically significant. Bcl-2 expression was found to be significantly high in mucinous carcinomas. Expression of c-ErbB-2 was observed in 12 of 86 (13.95 %) carcinomas. It was not detected in adenomas and normal mucosa. Although the incidence of c-ErbB-2 in nonmucinous carcinoma was higher than that of mucinous carcinoma, this was not significant. In addition we were unable to show any significant relation between c-ErbB-2 expression and other clinicopathologic features. Our result suggest that c-ErbB-2 protein expression in colorectal carcinomas, is not very frequent event. There is no correlation between c-ErbB-2 expression and malignant potential of colorectal carcinomas. Higher expressions of Bcl-2 in adenomas than carcinomas suggest us a possible role of Bcl-2 in early carcinogenesis of colon. However since we were unable to find any significant correlation between Bcl-2 expression and other parameters the impact of this gene on biological behavior is still unclear for us.     

Activation of Wnt signaling in the intestinal mucosa of Apc +/min mice does not cause overexpression of the receptor tyrosine kinase Met

The receptor tyrosine kinase MET is overexpressed in human colorectal adenomas and carcinomas, suggesting an instrumental role for MET signaling in the onset and progression of colorectal cancer. To corroborate this role, animal models are needed. To study the expression of Met in the normal and neoplastic mouse intestine, we generated an Armenian hamster monoclonal antibody against mouse Met. By using this antibody in immunohistochemical studies, we observed strong Met expression in fetal mouse intestinal epithelial cells. In contrast, in the intestines of adult mice, Met expression was very low whereas the protein was undetectable on the neoplastic epithelium of intestinal adenomas in Apc+/min mice. By immunoblotting, we were also unable to detect Met in intestinal adenomas, whereas Met mRNA levels in microdissected adenomas were very low. The absence of detectable Met protein expression in adenomas of Apc+/min mice contrasts sharply with the vast overexpression of the protein in adenomas of humans with familial adenomatous polyposis or sporadic colorectal carcinomas. Our results imply that deregulation of Wnt signaling in mouse--unlike in human--intestinal epithelium does not result in Met overexpression. Our findings thus reveal important interspecies differences in the regulation of Met expression during intestinal tumorigenesis.     

Prognostic significance of alpha-1-antitrypsin in early stage of colorectal carcinomas

We have previously shown that human colorectal carcinoma cell lines, RCM-1 and CoCM-1, synthesize alpha-1-antitrypsin (alpha 1-AT) in culture. We have studied immunohistochemically the incidence of alpha 1-AT on histologic sections from paraffin-embedded tissues of surgically resected colorectal carcinomas and their metastatic foci, polypectomized adenomas, and normal mucosae. alpha 1-AT was detected in 89 (61%) of 145 carcinomas (including 14 carcinomas in adenoma), and 12 (39%) of 31 adenomas. But only 2 (4%) of 55 normal colorectal mucosae were positive for alpha 1-AT. In metastatic tumor cells of colorectal carcinomas in lymph nodes and other organs, alpha 1-AT positivity was 60% and 82%, respectively. The incidence of alpha 1-AT was markedly higher in advanced adenocarcinomas than in early ones and more frequent in adenocarcinomas of right side (including transverse colon) than those of left side and rectum, regardless of their histological malignancy grades. In mucinous carcinomas the frequency was greater (8 of 9 cases) than in conventional adenocarcinomas. Clinical follow-up of the patients with colorectal carcinomas suggested that alpha 1-AT positivity in Dukes' stage A/B tends to correlate with unfavorable prognosis irrespective of the grade of histologic differentiation of carcinoma, but there is no significant relation in Dukes' stage C/D. Our findings suggest that alpha 1-AT in colorectal carcinoma is related to the invasive and metastatic capacity. It may thus serve as a biologic marker for prognosis of colorectal carcinomas at relatively early stages (Dukes' stage A/B).     

Quantitative analysis of estrogen receptor-alpha and -beta messenger RNA expression in normal and malignant thyroid tissues by real-time polymerase chain reaction.

OBJECTIVES: We have conducted a quantitative analysis of estrogen receptor-alpha (ER-alpha) and -beta (ER-beta) mRNA expression in normal thyroid and tumor tissues. METHODS: Normal thyroid tissues (n = 10) and tumor tissues [(follicular adenoma (n = 14), follicular carcinoma (n = 8), papillary carcinoma (n = 14), anaplastic carcinoma (n = 3) and medullary carcinoma (n = 6)] were obtained at surgery from 45 female patients. ER-alpha and ER-beta mRNA expression has been studied by a quantitative polymerase chain reaction. RESULTS: ER-alpha mRNA levels in the normal thyroid were not significantly different from those in follicular adenomas, papillary carcinomas and medullary carcinomas but were marginally (p = 0.08) higher than those in follicular and anaplastic carcinomas. ER-beta mRNA levels in the normal thyroid tissues were not significantly different from those in any other tumor tissues. ER-beta to ER-alpha mRNA ratios were significantly (p < 0.05) higher in the normal thyroid tissues than in follicular adenomas. Proportions of ER-beta mRNA variants (ER-beta 1, 2, 5, and 5') did not significantly differ among the normal and tumor tissues. CONCLUSIONS: A downregulation of ER-alpha mRNA in follicular and anaplastic carcinomas seems to suggest that estrogens are unlikely to play an important role in the carcinogenesis and progression of these carcinomas. On the other hand, a significant decrease in ER-beta to ER-alpha mRNA ratios in follicular adenomas suggests a possible involvement of estrogens in the pathogenesis of this disease since the same phenomenon has been reported on estrogen-dependent breast cancers.     

Prognostic and diagnostic significance of beta-catenin nuclear immunostaining in colorectal cancer.

In the present study, we investigated the prognostic and diagnostic significance of beta-catenin nuclear immunostaining in 60 specimens of normal colorectal tissue; 180 specimens of colorectal polyps, adenomas, and carcinomas; and 40 specimens from patients with the simultaneous occurrence of polyps, adenomas, and carcinomas. Additional specimens from 59 patients with colorectal carcinoma and 14 patients with adenoma who subsequently developed carcinoma were examined for possible survival study. Immunohistochemical staining showed that the occurrence of nuclear beta-catenin correlated with the sequential stages in colorectal carcinogenesis, in which positive staining was observed in 0% of normal tissues, 8% of polyps, 92% of adenomas, and 100% of carcinomas. High immunohistochemical scores in colorectal carcinoma were significantly associated with lymph node metastasis and poor survival. Adenomas associated with synchronous or metachronous carcinomas showed significantly higher levels of nuclear beta-catenin compared with adenomas without associated carcinomas. Nuclear translocation of beta-catenin was rare or absent in other types of cytokeratin 20 positive adenocarcinomas examined (99 cases). Thus, it was positive in only 7% of colonic mucinous adenocarcinomas, 3% of pancreatic adenocarcinomas, 8% of ovarian mucinous cystadenocarcinomas, and 0% of gastric adenocarcinomas. However, 100% of primary and metastatic colorectal adenocarcinomas were positive for nuclear staining for beta-catenin. Thus, nuclear staining for beta-catenin may serve as an additional parameter to help distinguish colorectal adenocarcinomas from adenocarcinomas of other tissue sites. Collectively, the present large-scale study has clearly addressed the clinical significance of beta-catenin nuclear translocation with respect to tumor progression, survival, and differential diagnosis.     

Detection of mRNAs of Carcinoembryonic Antigen and Nonspecific Cross-reacting Antigen Genes in Colorectal Adenomas and Carcinomas by in situ Hybridization

Expression of mRNAs of carcinoembryonic antigen (CEA) and nonspecific cross-reacting antigen (NCA) genes in colorectal carcinomas and adenomas was investigated by in situ hybridization (ISH) with specific biotinylated probes. Hybridization was clearly detected throughout the cytoplasm of 7 out of 15 adenomas and 13 out of 15 carcinomas with the CEA cDNA probe, and in 6 out of 15 adenomas and 10 out of 15 carcinomas with the NCA cDNA probe. The intensity of signal appeared to be stronger in carcinomas than that in adenomas, and the CEA and NCA mRNAs were expressed together in most of the positive tissue specimens. On the other hand, noninvaded tissues adjacent to the carcinoma did not show any signal except for 4 cases faintly stained with the NCA probe. This finding was partly confirmed by Northern blot analysis which indicated that the specific bands for the CEA and NCA mRNAs were more intense in RNAs from carcinoma tissues than in those from adjacent noninvaded tissues. These data suggest that the ISH technique with biotinylated probes could be of use for analyzing expression and localization of CEA and related genes on tissue sections.     

Detection of mRNAs of carcinoembryonic antigen and nonspecific cross-reacting antigen genes in colorectal adenomas and carcinomas by in situ hybridization

Expression of mRNAs of carcinoembryonic antigen (CEA) and nonspecific cross-reacting antigen (NCA) genes in colorectal carcinomas and adenomas was investigated by in situ hybridization (ISH) with specific biotinylated probes. Hybridization was clearly detected throughout the cytoplasm of 7 out of 15 adenomas and 13 out of 15 carcinomas with the CEA cDNA probe, and in 6 out of 15 adenomas and 10 out of 15 carcinomas with the NCA cDNA probe. The intensity of signal appeared to be stronger in carcinomas than that in adenomas, and the CEA and NCA mRNAs were expressed together in most of the positive tissue specimens. On the other hand, noninvaded tissues adjacent to the carcinoma did not show any signal except for 4 cases faintly stained with the NCA probe. This finding was partly confirmed by Northern blot analysis which indicated that the specific bands for the CEA and NCA mRNAs were more intense in RNAs from carcinoma tissues than in those from adjacent noninvaded tissues. These data suggest that the ISH technique with biotinylated probes could be of use for analyzing expression and localization of CEA and related genes on tissue sections.     

Investigation of human papillomavirus DNA in colorectal carcinomas and adenomas

Human papillomavirus (HPV) has been considered to be an etiological agent for anogenital cancers, such as cervical cancer and possibly a subset of cancers of the aerodigestive tract. The aim of the study was to evaluate the presence of human papillomavirus DNA in colorectal carcinomas and adenomas. Formalin-fixed and paraffin-embedded archival tissue samples were used for DNA extraction. One hundred and six colorectal carcinomas and 62 adenomas were screened by nested polymerase chain reaction (PCR) for HPV DNA with a control group of 49 cervical tissues with invasive cervical carcinoma and cervical intraepithelial neoplasia (CIN). In the study group, we did not find HPV DNA positivity in any of all the colorectal carcinomas and adenomas. In the control group with cervical lesions, 34 out of 49 (69.4%) samples were positive for the HPV DNA. These results indicated that there was no correlation between HPV infection and colorectal carcinomas and adenomas.     

ITF-2B protein levels are correlated with favorable prognosis in patients with colorectal carcinomas

The majority of sporadic forms of colorectal carcinomas is characterized by deregulation of Wnt/β-catenin signaling early in colorectal carcinogenesis. As a consequence, ITF-2B protein levels are increased in adenomas of these patients. However, ITF-2B protein levels are strongly reduced with increasing carcinoma stages, suggesting that reduction of ITF-2B protein is required for progression of adenomas to colorectal carcinomas. To find out if ITF-2B protein levels are correlated with the survival of patients with colorectal carcinomas, a tissue microarray containing samples from 213 colorectal carcinomas (T-categories T2 and T3) with corresponding survival information was stained with an ITF-2B antibody. In addition, we analyzed if detection of ITF-2B in microsatellite instable and microsatellite stable carcinomas as well as in colorectal carcinomas with KRAS mutations is correlated with survival. Detection of cytoplasmic ITF-2B protein was associated with better overall and progression free survival of patients with colorectal carcinomas (P=0.033 and 0.024, respectively). Multivariate Cox regression analysis revealed an increased risk to suffer from poor overall survival and recurrent disease if no cytoplasmic ITF-2B was detectable (HR=1.91; P=0.033 and HR=1.75; P=0.033, respectively). Similarly, patients with MSS carcinomas had a better overall survival, if they showed cytoplasmic positivity for ITF-2B (P=0.013). Remarkably, patients with colorectal carcinomas carrying KRAS mutations had a better overall and progression free survival rate if the carcinomas were positive for cytoplasmic ITF-2B (HR=4.71; P=0.002 and HR=2.57; P=0.024, respectively). These data suggest that cytoplasmic protein levels of ITF-2B could be used as a prognostic marker for patients with colorectal carcinomas.     

Hepatocyte growth factor sensitizes human ovarian carcinoma cell lines to paclitaxel and cisplatin

The hepatocyte growth factor (HGF) receptor, encoded by the MET oncogene, is expressed in approximately 70% of human ovarian carcinomas and overexpressed in 30% of cases. Because HGF is known to protect cells from apoptosis, we investigated whether receptor expression modifies ovarian cancer cell response to chemotherapy. The apoptotic effect of the front-line chemotherapeutic drugs paclitaxel and cisplatin on cells treated with HGF was studied. In ovarian cancer cell lines, pretreatment with HGF surprisingly enhances the apoptotic response to low doses of paclitaxel and cisplatin. HGF empowers specifically the intrinsic apoptotic pathway, whereas it protects cells from extrinsic Fas-induced apoptosis. Chemotherapy sensitization is specific for HGF because another growth factor (e.g., epidermal growth factor) increases ovarian cancer cell survival. In nonovarian cancer cell models, as expected, HGF provides protection from drug-induced apoptosis. These data show that HGF sensitizes ovarian carcinoma cells to low-dose chemotherapeutic agents. This suggests that HGF may be used to improve response to chemotherapy in a set of human ovarian carcinomas molecularly classified based on the MET oncogene expression.     

Expression of p53, p21/waf, bcl-2, bax, Rb and Ki67 proteins in colorectal adenocarcinomas

This study investigated the combined immunoexpression of p53, p21, bcl-2, bax, Rb and Ki67 proteins in colorectal adenocarcinomas and correlated expression patterns with tumour stage and grade. Paraffin sections from 98 cases of colorectal adenocarcinomas were stained by immunohistochemistry for p53, p21, bcl-2, bax, Rb and MIB-1 (Ki67) proteins. In addition, 12 cases of colorectal adenomas and normal colorectal mucosa were studied in parallel. P53, p21, bcl-2, bax, Rb and Ki67 proteins were detected in at least 5% of tumour cells in 63/98, 72/98, 52/98, 96/98 and 98/98 adenocarcinomas, respectively. Comparative study of the normal-adenoma-carcinoma tissues revealed abrogation of the normal immunotopography in adenomas and adenocarcinomas, and considerable modifications, increase or reduction, of the expression of p53, p21, bcl-2, bax, Rb and Ki67 proteins in adenocarcinomas when compared with normal mucosa and adenomas. Statistically significant correlations were found between low bax expression and Dukes C stage of carcinomas, Ki67 expression and carcinoma grade, and Ki67 and Rb expression. P53, p21, bcl-2 and Rb immunoexpression did not correlate with tumour stage or grade. Our findings show that low bax immunoexpression is frequently related to colorectal adenocarcinomas with lymph node metastases suggesting that low levels of bax expression play a role in late stage colorectal cancer. The correlation between Ki67 and Rb expression, in view of previous data that the hyperphosphorylated inactive Rb protein is frequently increased in colorectal adenocarcinomas, suggests that Rb protein is somewhat ineffective in inhibiting the cell-cycle progression in these malignancies. Furthermore, our findings provide immunohistochemical evidence that the abrogation of the normal immunotopography and the modifications of the expression of p53, p21, bcl-2, bax, Rb and Ki67 proteins reflect important events in colorectal oncogenesis.     

Correlation of Skp2 with carcinogenesis, invasion, metastasis, and prognosis in colorectal tumors

In colorectal tumors, S-phase kinase-associated protein 2 (Skp2) still has numerous important questions unanswered: its expression in adenomas, its correlation with key clinicopathological indices, its association with patient prognosis, its variation in lymph node metastases, and its association with many cell-cycle regulators. To answer these questions in colorectal tumors, Skp2, cyclin A, cyclin B1, cyclin E, CDK2, and Ki67 were immunohistochemically stained in 12 normal mucosa, 36 adenomas, 11 carcinomas in adenomas, 102 primary carcinomas, and 12 paired lymph node metastases; and Skp2 was examined by Western blot in 8 pairs of normal mucosa and carcinomas. Situated in nuclei, Skp2 expression significantly increased from normal mucosa through adenoma to primary carcinoma (p<0.0001), from mild through moderate to severe dysplasia in adenomas (p=0.038), from peripheral adenoma to paired central carcinoma (p=0.0033), and from primary carcinoma to lymph node metastasis (p=0.015), and these increases were confirmed by Western blot. Expression, however, relatively declined significantly in the primary carcinomas showing deep invasion (p=0.0113), lymph nodal metastases (p=0.0268), and poor prognosis for all (p=0.0104) or stage III patients (p=0.0119). High Skp2 was also significantly linked with elevated cyclin A, cyclin B1, cyclin E, CDK2 (in primary carcinomas only), and Ki67 in both adenomas and primary carcinomas. Thus, overexpression of Skp2 is associated with colorectal carcinogenesis and late metastasis to lymph nodes, whereas relative reduction of Skp2 is correlated with local invasion of primary carcinoma.     

Arg-1在大肠炎症相关性肿瘤中的表达及意义

目的 观察精氨酸酶-1(Arg-1)在小鼠及人的大肠炎症相关性肿瘤组织中的表达情况,分析其与大肠癌患者临床病理因素、增殖和预后的关系。方法 采用免疫组化方法观察Arg-1在20例小鼠大肠炎-癌模型中的表达情况,同时观察Arg-1在20例患者大肠的癌旁组织、15例炎症组织、110例癌症组织中的表达情况。应用统计学分析Arg-1在小鼠及人的大肠组织中不同组间的差异表达情况。结果 Arg-1在小鼠大肠的正常组织、慢性炎症组织、腺瘤组织、炎癌组织中表达逐渐升高,具有统计学意义(P＜0.05);Arg-1在患者大肠的癌旁组织、炎症组织、癌症组织中的表达也逐步增高,具有统计学意义(P＜0.05)。结论 Arg-1蛋白与大肠癌的TNM分期密切相关,其可能参与大肠炎症相关性肿瘤的发生与发展过程,并可能成为评估结直肠癌增殖程度及判断预后的候选标志物。     

Expression of cripto, a novel gene of the epidermal growth factor family, in human gastrointestinal carcinomas

The expression of mRNA for cripto gene, a novel transforming gene of the epidermal growth factor family, was examined in 20 alimentary tract carcinoma cell lines, 60 surgically resected tumor tissues and their adjacent normal mucosas. Although the cripto mRNA was not detected in esophageal carcinomas or in normal mucosas, it was detected in gastric and colorectal carcinomas. In gastric carcinomas, 2.2 kb cripto mRNA was detected in one cell line, all the gastric carcinoma tissues and their adjacent normal mucosas. Of 23 gastric tumor tissues 8 (34.8%) exhibited a higher mRNA level than normal gastric mucosas. cripto mRNA was detected in 2 out of 6 colorectal carcinoma cell lines. Interestingly, 18 (81.8%) out of 22 colorectal carcinoma specimens expressed a higher level of cripto mRNA than that in normal mucosas. The level of the expression was higher than that in gastric carcinoma tissues. The expression was also correlated to tumor stage of colorectal carcinomas.