Expression of urokinase plasminogen activator, its receptor and type-1 inhibitor in malignant and benign prostate tissue

The plasminogen activation (PA) cascade participates in degradation of extracellular matrix during cancer invasion. We have studied the expression of urokinase-type plasminogen activator (uPA) mRNA, uPA receptor (uPAR) mRNA and immunoreactivity, and type-1 plasminogen activator inhibitor (PAI-1) mRNA and immunoreactivity in 16 prostate adenocarcinomas and 9 benign prostate hyperplasias. uPA mRNA and uPAR mRNA expression were found in 9 and 8 of the adenocarcinomas, respectively, and in 7 and 6 of the benign hyperplasias, respectively. In both malignant and benign lesions, expression of these 2 mRNAs was predominantly seen in cells identified as macrophages, which in most of the carcinomas (approximately 90%) were located in the interstitial tissue between the tumor cell islands, while in most of the benign hyperplasias they were located in the lumen of the glands and were in only a few cases (approximately 30%) found in the interstitial tissue. uPAR immunoreactivity correlated with the mRNA expression and was, in addition, found in neutrophils. PAI-1 mRNA was detected in 13 of the 16 carcinomas and in 8 of the 9 benign hyperplasias, located in scattered fibroblast-like cells in both groups, in some vascular structures and in a few macrophages located in the interstitial tissue of both malignant and benign lesions. A similar expression pattern was found for PAI-1 immunoreactivity. In 8 of the 16 carcinomas, all 3 components were present, and in several areas colocalization was observed in stromal cells in close proximity to cancer cell islands. No immunoreactivity and/or mRNA expression of uPA, uPAR or PAI-1 was observed in cancer cells or in other epithelial cells in any of the cases.     

Urokinase-type plasminogen activator expression correlates with tumor angiogenesis and poor outcome in gastric cancer

Urokinase plasminogen activating system (PA system) and vascular endothelial growth factor (VEGF) were recently suggested to contribute synergistically to tumor progression. To evaluate the roles of the PA system and VEGF in gastric cancer, the effects of the PA system and VEGF on tumor angiogenesis and the survival of patients with gastric cancer were investigated. Cancer tissues from 101 gastric cancer patients were assayed immunohistochemically for expression of urokinase-type plasminogen activator (uPA), uPA receptor (uPAR), PA inhibitor-1 (PAI-1) and VEGF protein. The positive rates of uPA, uPAR, PAI-1, VEGF expression were 22.8%, 32.7%, 36.6% and 26.7%, respectively. Positive staining was observed in tumor cells (uPA, uPAR, VEGF), or in both tumor cells and stromal cells (PAI-1). The expressions of uPA, uPAR, PAI-1 and VEGF were significantly correlated with the clinicopathological factors: uPA, depth of tumor invasion, differentiation, lymphatic and vascular invasion; uPAR, tumor size, depth, lymph node involvement, differentiation, vascular invasion; PAI-1, tumor size, depth, lymph node involvement, differentiation, vascular invasion; VEGF, differentiation, vascular invasion. The microvessel density (MVD) assessed immunohistochemically was significantly higher in the patients with expression of uPA, uPAR or VEGF, and stepwise analysis identified uPA as an independent correlated factor with MVD. Furthermore, multivariate analysis demonstrated that depth of tumor invasion, lymph node involvement and uPA expression were independent prognostic factors. uPA is a key factor in the PA system, being associated with a poor outcome of gastric cancer, and contributing not only to invasive activity, but also to angiogenesis. (Cancer Sci 2003; 94: 43–49)     

Urokinase plasminogen activator system gene expression is increased in human breast carcinoma and its bone metastases — A comparison of normal breast tissue, non-invasive and invasive carcinoma and osseous metastases

The urokinase plasminogen activator (uPA) system has been widely associated with the development of breast carcinoma. However, the role of the urokinase pathway in the development of osseous breast cancer metastases has been largely overlooked. We studied the expression of uPA, urokinase plasminogen activator receptor (uPAR) and plasminogen activator inhibitor type-1 (PAI-1) in human breast carcinomas and their bone metastases, using in situ hybridisation. Studies were performed using paraffin-embedded tissue from 13 ductal carcinomas, 23 invasive ductal carcinomas, five normal breasts and 25 bone metastases. The majority of the tumours examined expressed low to moderate levels of uPA mRNA and low to high levels of uPAR and PAI-1 mRNA, which was predominantly localised to the epithelial tumour cells. There was slight over-expression of uPA and PAI-1 mRNA and a marked increase in uPAR mRNA expression in the malignant tumours compared with benign tissue. Overall, uPAR and PAI-1 mRNA expression was found to be more variable than uPA mRNA, suggesting a possible role of the receptor and inhibitor in the regulation of uPA activity. Increased 1(I) procollagen (COL) and osteopontin (OPN) mRNA expression was detected, primarily in the stromal cells, in malignant tumours compared with the benign tissue. The increased expression of the components of the uPA system on the epithelial tumour cells may account for the activation of the proteolytic cascade that occurs during breast cancer metastasis to bone. Furthermore, the over-expression of COL and OPN suggests a possible interaction between these matrix proteins and the uPA system.     

Urokinase-type plasminogen activator system in breast cancer: association with tamoxifen therapy in recurrent disease

The prognostic value of components of the urokinase-type plasminogen activator (uPA) system, its receptor uPAR (CD87), and plasminogen activator inhibitors PAI-1 and PAI-2 is well established. We studied the predictive value of these proteolytic factors by evaluating the association of their tumor expression level and the efficacy of tamoxifen therapy in patients with recurrent breast cancer. The antigen levels of the four factors were determined by ELISA in cytosols prepared from estrogen receptor-positive primary breast tumors of 691 hormone-naive breast cancer patients with recurrent disease and treated with tamoxifen as first-line systemic therapy. High tumor levels of uPA (P < 0.001), uPAR (P < 0.01), and PAI-1 (P = 0.01) were associated with a lower efficacy of tamoxifen therapy. In the multivariable analysis, uPA (P < 0.001) provided additional information independent of the traditional predictive factors to predict benefit from tamoxifen therapy. High levels of uPA, uPAR, and PAI-1 predicted a shorter progression-free survival (PFS) on tamoxifen in an analysis of the first 9 months of therapy. However in the analysis during the total follow-up period, high PAI-2 levels (P = 0.01) showed a longer response to tamoxifen. In conclusion, uPA, uPAR, and PAI-1, components of the urokinase system, are predictive for the efficacy of tamoxifen therapy in patients treated for recurrent breast cancer. Knowledge of their tumor expression levels might be helpful for future individualized therapy protocols, including possible new-targeted therapies based on the interference in the urokinase system.     

Increased expression of urokinase plasminogen activator and its cognate receptor in human seminomas

Background  

The urokinase plasminogen activating system (uPAS) is implicated in neoplastic progression and high tissue levels of uPAS components correlate with a poor prognosis in different human cancers. Despite that, relative few studies are available on the expression and function of the uPAS components in human seminomas. In the present study we characterized the expression of the urokinase plasminogen activator (uPA), its cognate receptor (uPAR) and the uPA inhibitors PAI-1 and PAI-2 in normal human testis and seminomas.     

Differential expression of the components of the plasminogen activating system in human thyroid tumour derived cell lines and papillary carcinomas

We characterised the expression of the plasminogen activators (uPA and tPA), the uPA receptor (uPAR) and the PAs inhibitors (PAI-1 and PAI-2) in human thyroid cell lines derived from normal thyroid, follicular adenoma, follicular, papillary and anaplastic carcinomas. Urokinase PA activity was detected in the supernatant of normal thyrocytes and augmented in those of all tumour cells. Quantitative RT-PCR analysis showed that uPA, uPAR and PAI-1 mRNAs increased in all carcinoma cells. Similar results were found in 13 papillary thyroid carcinoma (PTC) tissues which were mirrored in Western blot experiments. A correlation was found between tumour size and uPA mRNA increase, and higher levels of uPA and uPAR mRNAs were found in metastatic PTC. In conclusion, thyroid carcinoma cell lines and PTC overexpress uPA, uPAR and PAI-1 and the correlation of uPA and its cognate receptor with tumour size and metastasis may suggest their potential prognostic relevance in thyroid cancer.     

Correlation of tissue and blood plasminogen activation system in breast cancer

The plasminogen activation system plays a crucial role during cancer invasion and metastasis. In the solid tumor, urokinase-type plasminogen activator (uPA), plasminogen activator inhibitor type-1 (PAI-1) and uPA receptor (uPAR) are considered as prognostic factors. In this study, we have investigated whether secretion of the uPA, PAI-1 and uPAR from the primary breast cancer tissue can be detected in the blood of the patients using the ELISA assay. We have found that the plasminogen activation system (uPA, PAI-1, uPAR) of tumor tissue is activated from the early stage of breast cancer. However, only a number of metastatic lymph nodes was a prognostic factor in multivariate analysis for relapse. The blood level of the plasminogen activation system correlated with that of tissue in an order of uPAR (r²=0.61; P=0.001), uPA (r²=0.35; P=0.001) and PAI-1 (r²=0.11; P=0.001). We conclude that the total uPAR level of cancer tissue can be substituted by that which is detected in the blood for further clinical applications.     

Dedifferentiation of serous ovarian cancer from cystic to solid tumors is associated with increased expression of mRNA for urokinase plasminogen activator (uPA), its receptor (uPAR) and its inhibitor (PAI-1)

The plasminogen activating system is involved in tumor growth and metastasis by degradation of extracellular matrix, and modulation of cell adhesion and migration. Benign and well-differentiated malignant ovarian tumors present as cystic lesions with preserved glandular morphology, whereas poorly differentiated tumors and metastases are solid with characteristic absence of glandular morphology. We analyzed the mRNAs for urokinase plasminogen activator (uPA), its receptor (uPAR), and inhibitor (PAI-1) in serous ovarian tumors by in situ hybridization and by densitometric scanning of Northern blots prepared from tissue extracts. The mRNA expressing cells in the in situ hybridization sections were evaluated and counted by two different observers. The number of mRNA expressing cells for uPA, uPAR and PAI-1 were all significantly increased in solid as compared with cystic malignant tumors. The increased expression of all three mRNA species was mainly located in the stroma of poorly differentiated tumors and metastases. Apart from being expressed in the stroma of these tumors, uPAR mRNA was also expressed by tumor cells located along the stromal/epithelial boarder. In addition, the tumor tissue content of uPA, uPAR and PAI-1 mRNAs as measured by Northern blots were higher in the solid as compared with the cystic tumors. Increased expression of uPA, uPAR and PAI-1 genes in the solid tumors suggest a correlation with a more aggressive phenotype.     

非霍奇金淋巴瘤外周血尿激酶型纤溶酶原激活物及其受体测定的临床意义

 目的 研究非霍奇金淋巴瘤（NHL）患者血中尿激酶型纤溶酶原激活物（uPA）、尿激酶型纤溶酶原激活物受体（uPAR）、纤溶酶原激活剂抑制物-1（PAI-1）水平与NHL发生、发展及预后的关系。方法 采用ELISA方法检测38例初治NHL患者血中uPA,uPAR 及PAI-1水平,分析与不同临床分期、治疗效果、乳酸脱氢酶（LDH）的相关性。结果 NHL患者血uPA,uPAR及PAI-1水平均高于正常对照组（P＜0.05）, NHL患者LDH值增高组与LDH正常组比较uPAR增高（P＜0.05）,uPA,uPAR与LDH三者之间呈正相关（P＜0.01）。结论 uPA及可溶性uPA 受体（suPAR）在NHL的发生、发展中起作用,suPAR可以作为判断NHL肿瘤负荷和预后的指标。     

Quantitative expression of protein markers of plasminogen activation system in prognosis of colorectal cancer

BACKGROUND AND OBJECTIVES: Certain pathophysiological markers may be helpful in selecting further therapies for patients with resected colorectal cancer (CRC). The aim of this study was to determine whether expression of proteins of the plasminogen activation system (PAS), which are important in tumor spread and growth, can predict outcome of human CRC. METHODS: Protein expression of the PAS, including urokinase-type plasminogen activator (uPA) and its receptor (uPAR), plasminogen (Plg), and plasminogen activator inhibitors-1 and -2 (PAI-1 and PAI-2), was determined in the colonic tissue samples of 56 patients with resected primary CRC by quantitative immunohistochemistry and correlated with clinicopathological parameters and patient outcome. RESULTS: Overexpression of uPA (t-test, P < 0.001), uPAR (P < 0.001) and PAI-1 (P = 0.031) was significantly associated with liver metastatic CRC tumors. Higher uPA or uPAR expression level was significantly correlated with overall survival (OS; log-rank, P = 0.001 and P < 0.0001) and cancer-specific survival (CSS; P = 0.001 and P < 0.0001) after the first CRC resection. The predictive value of both uPA and uPAR in liver metastasis, OS and CSS was independent from other parameters (multivariate Cox regression: all P < 0.001). CONCLUSIONS: uPA and uPAR may be independent predictors of liver metastasis, patient overall survival and cancer-specific survival after resection of colorectal tumors.     

Urokinase receptor and vascular endothelial growth factor are synergistically associated with the liver metastasis of colorectal cancer.

Considering recent findings that the urokinase plasminogen activation (PA) system is involved in invasion and vascular endothelial growth factor (VEGF) is involved in angiogenesis of colorectal cancer, we evaluated these factors in the liver metastasis of primary colorectal cancer. Cancer tissues from 71 colorectal cancer patients were assayed quantitatively for antigen levels of urokinase type plasminogen activator (uPA), uPA receptor (uPAR), and plasminogen activator inhibitor-1 and -2 (PAI-1, PAI-2), and were also assayed immunohistochemically for expression of VEGF protein. Among the PA system factors, both the levels of uPAR and PAI-1 were significantly higher in larger tumors than in smaller ones, and were also significantly higher in tumors that invaded subserosa, serosa or adjacent organs than in mucosal, submucosal tumors or in tumors that invaded the muscle layer. The uPAR levels were significantly higher in tumors with liver metastasis than in those without. VEGF overexpression was significantly more frequent in tumors with lymph node involvement or liver metastasis than in those without. Among the PA system factors, the uPAR levels were significantly higher in tumors with VEGF overexpression and a multivariate analysis revealed that high uPA level and VEGF overexpression were independent risk factors for liver metastasis. The combination of high uPAR level and overexpression of VEGF was associated with the worst prognosis in patients with colorectal cancer. These results suggest that uPAR and VEGF might contribute synergistically to the liver metastasis of colorectal cancer.     

Urokinase Receptor and Vascular Endothelial Growth Factor Are Synergistically Associated with the Liver Metastasis of Colorectal Cancer

Considering recent findings that the urokinase plasniinogen activation (PA) system is involved in invasion and vascular endothelial growth factor (VEGF) is involved in angiogenesis of colorectal cancer, we evaluated these factors in the liver metastasis of primary colorectal cancer. Cancer tissues from 71 colorectal cancer patients were assayed quantitatively for antigen levels of urokinase type plasminogen activator (uPA), uPA receptor (uPAR), and plasminogen activator inhibitor-1 and -2 (PAI-1, PAI-2), and were also assayed immunohistochemically for expression of VEGF protein. Among the PA system factors, both the levels of uPAR and PAI-1 were significantly higher in larger tumors than in smaller ones, and were also significantly higher in tumors that invaded subserosa, serosa or adjacent organs than in mucosal, submucosal tumors or in tumors that invaded the muscle layer. The uPAR levels were significantly higher in tumors with liver metastasis than in those without. VEGF overexpression was significantly more frequent in tumors with lymph node involvement or liver metastasis than in those without. Among the PA system factors, the uPAR levels were significantly higher in tumors with VEGF overexpression and a multivariate analysis revealed that high uPA level and VEGF overexpression were independent risk factors for liver metastasis. The combination of high uPAR level and overexpression of VEGF was associated with the worst prognosis in patients with colorectal cancer. These results suggest that uPAR and VEGF might contribute Synergistically to the liver metastasis of colorectal cancer.     

The urokinase-type plasminogen activator system in resected non-small-cell lung cancer

Background:Urokinase-type plasminogen activator (uPA), itsreceptor (uPAR) and plasminogen activator inhibitors (PAI-1 and PAI-2), allplay important roles in tumour invasion and metastasis. The tumour levels ofthe components of the urokinase-type plasminogen activator system (uPA-system)may help to identify individuals with a poor prognosis in postoperativenon-small-cell lung cancer (NSCLC) patients. Patients and methods:The levels of uPA, uPAR PAI-1 and PAI-2 weremeasured by enzyme-linked immunosorbent assay (ELISA) in triton-extracts,prepared from 88 NSCLC tissues (stage I–IIIa) and 74 normal lung tissuesfrom the same patients. Results:The expression levels of uPA, uPAR, PAI-1 and PAI-2 weresignificantly higher in tumour tissues as compared to their normal equivalents(all, P < 0.0001). Significant relations were found between genderand uPA (P = 0.04) or uPAR (P < 0.001), and between PAI-2and pathological stage (P = 0.03). For none of the studied factorsof the uPA-system a significant relation with survival was found, neither inall patients, nor in the subgroups of patients with squamous-cell lungcarcinoma or adenocarcinoma. Conclusions:The expression levels of the components of theuPA-system were higher in NSCLC tissue as compared to normal lung tissue, butthere were no significant relationships between their levels and survival.     

Oestradiol regulation of the components of the plasminogen-plasmin system in MDA-MB-231 human breast cancer cells stably expressing the oestrogen receptor.

To understand the hormonal regulation of the components of the plasminogen-plasmin system in human breast cancer, we examined the oestradiol (E2) regulation of plasminogen activators (PAs), namely urokinase-type plasminogen activator (uPA) and tissue-type plasminogen activator (tPA), plasminogen activator inhibitor type 1 (PAI-1) and uPA receptor (uPAR), in our model system. We used stable transfectants of the MDA-MB-231 human breast cancer cells that express either the wild-type (S30 cells) or the mutant 351asp-->tyr oestrogen receptor (ER) (BC-2 cells). Northern blot analysis showed that there was a concentration-dependent down-regulation of uPA, tPA and PAI-1 mRNAs by E2. In contrast, uPAR mRNA was not modulated by E2. The pure anti-oestrogen ICI 182,780 was able to block E2 action, indicating that the regulation of these genes is ER mediated. The E2 also inhibited the expression and secretion of uPA, tPA and PAI-1 proteins as determined by enzyme-linked immunosorbent assay (ELISA) in cell extracts (CEs) and conditioned media (CM). Zymography of the CM confirmed the inhibitory effect of E2 on uPA activity. Thus, we now report the regulation of uPA, PAI-1 and tPA by E2 in both mRNA and protein levels in ER transfectants. The association between down-regulation of the uPA by E2 and known E2-mediated growth inhibition of these cells was also explored. Our findings indicate that down-regulation of uPA by E2 is an upstream event of inhibitory effects of E2 on growth of these cells as the addition of exogenous uPA did not block the growth inhibition by E2.     

Expression of urokinase-type plasminogen-activator (upa) and its receptor (upar) in human ovarian-cancer cells and in-vitro invasion capacity

Expression of urokinase-type plasminogen activator (uPA), tissue-type plasminogen activator (t-PA), their inhibitor PAI-1 and the uPA-receptor (uPAR) was characterized in six human tumor cell lines (OV-MZ-6, -10, -13, -15, -19 and OVCAR-3) established from patients with cystadenocarcinoma of the ovary. The invasive potential of the ovarian cancer cell lines determined in an in vitro invasion assay did neither correlate with the antigen level of uPA, t-PA, PAI-1 or uPAR nor with the cell surface uPA activity, however, did correlate with the cell surface-bound plasmin activity. The in vitro invasiveness of three cancer cell lines selected displaying a different pattern of uPA and uPAR expression was significantly inhibited by a recombinant soluble truncated form of the uPAR functioning as a scavenger for uPA. Our results suggest that the interference of the uPA/uPAR interaction leads to a reduced in vitro invasiveness of human ovarian cancer cells independent of the level of uPA and uPAR expression.     

Larger and more invasive colorectal carcinoma contains larger amounts of plasminogen activator inhibitor type 1 and its relative ratio over urokinase receptor correlates well with tumor size

BACKGROUND: Considering recent findings that both urokinase plasminogen activator receptor (uPAR) and plasminogen activator inhibitors (PAIs) are involved in tumor growth through an urokinase-type plasminogen activator (uPA) activity-independent mechanism, the relation between the presence of these factors in tumor tissue and the clinicopathologic variables in colorectal carcinoma was reevaluated. METHODS: In 100 colorectal carcinoma patients, antigen levels of u-PA, uPAR, and PAI-1 and PAI-2 were assayed in both tumor tissues and their normal counterparts. Plasma levels of soluble uPAR also were determined. RESULTS: All uPAR, uPA, PAI-1, and PAI-2 antigen levels in tumor tissue were significantly higher than those in normal tissue. Levels of both uPAR and PAI-1 were significantly higher (3.09 +/- 1.37 and 6.63 +/- 7.49, respectively) in large tumors (>/=50 mm in greatest dimension) than those in smaller tumors (< 50 mm) (2.50 +/- 1.07 and 2.72 +/- 2.70, respectively) (P < 0.05). Significant positive correlation coefficients (r) were obtained between tumor size and the calculated ratios of PAI-1/uPAR (r = 0.490; P < 0.0001) and PAI-1/uPA (r = 0. 469; P < 0.0001). In addition to liver metastases (P = 0.004) and lymph node involvement (P = 0.04), high levels of uPAR (P = 0.05) also were found to be of independent prognostic value by multivariate analysis. CONCLUSIONS: Higher expression of uPAR was related to poor prognosis of patients with colorectal carcinoma and excess amounts of PAI-1 over uPAR or uPAR-bound uPA appeared to play an important role in tumor progression.     

Measurement of plasminogen activator system components in plasma and tumor tissue extracts obtained from patients with breast cancer: an EORTC Receptor and Biomarker Group collaboration

The plasminogen activator (PA) system comprises the 2 serine proteases, urokinase PA (uPA) and tissue PA (tPA), the 2 serpin inhibitors, PAI-1 and PAI-2 and the uPA receptor (uPAR; CD87). High levels of uPA, PAI-1, uPA-PAI-1 complex and uPAR in breast cancer tissue are associated with poor prognosis, while high levels of tPA or PAI-2 correlate with good prognosis. In this study, pre-operative plasma levels of uPA, PAI-1, uPAR, tPA, uPA-PAI-1 complex, and tPA-PAI-1 complex were measured in patients with benign (n=103) and malignant breast disease (n=113) by immunoenzymatic assays (ELISA). While plasma antigen levels of uPA, PAI-1, uPA-PAI-1 complex and uPAR were not significantly different in the 2 groups, antigen levels of tPA and tPA-PAI-1 complex were significantly higher in patients with breast carcinoma compared to the control group. In plasma from the breast cancer patients, uPA levels correlated weakly but significantly with those of tPA (r=0.20, p=0.035) and uPAR (r=0.208, p=0.028). tPA levels correlated strongly with tPA-PAI-1 complex (r=0.972, p=0.0001) while uPA-PAI-1 levels were significantly associated with PAI-1 levels (r=0.534, p<0.0001), tPA levels (r=0.348, p=0.0003) and tPA-PAI-1 levels (r=0.356, p=0.002). However, no significant correlation was found between plasma and tumor tissue levels of uPA, PAI-1, uPA-PAI-1 complex, tPA or tPA-PAI-1. Our findings indicate that determination of these factors in plasma do not reflect their concentration in tumor tissue. Therefore, measurement of PA components in blood cannot be recommended for assessing prognosis in breast cancer.     

二甲基阿米洛利对高转移性肺癌细胞侵袭能力的影响及其作用机制

目的:研究二甲基阿米洛利(dimethyl amiloride, DMA)对人高转移性肺癌PGCL3细胞体外侵袭能力的影响,并探讨其可能的作用机制.方法:肺癌PGCL3细胞经DMA处理后,用Transwell小室法检测其对细胞侵袭和运动能力的影响,发色底物法检测DMA对细胞分泌的尿激酶型纤溶酶原激活物(urokinase-type plasminogen activator, uPA)和纤溶酶原激活物抑制剂1(plasminogen activator inhibitor-1, PAI-1)活性的影响,RT-PCR检测DMA对细胞uPA、尿激酶型纤溶酶原激活物受体(urokinase-type plasminogen activator receptor, uPAR)和PAI-1 mRNA表达的影响,Western印迹法检测细胞外调节蛋白激酶2(extracellular regulated protein kinases 2,ERK2)和ras蛋白表达的变化.结果:DMA能抑制PGCL3细胞的体外侵袭和运动能力,下调uPA、uPAR和PAI-1的mRNA表达,上调ras蛋白的表达;高浓度时DMA可降低细胞分泌的uPA活性,但对分泌型PAI-1活性和ERK2蛋白表达无影响.结论:DMA能抑制高转移性肺癌PGCL3细胞的侵袭和运动,其作用机制可能与抑制uPA系统的表达有关.     

The Plasminogen System in Microdissected Colonic Mucosa Distant from an Isolated Adenoma

In the colon, the urokinase-type plasminogen activator (uPA), its receptor (uPAR), and plasminogen activator inhibitors, PAI-1 and PAI-2, are implicated in the transition from mucosa to adenoma and tumour progression. However, expression in the mucosa adjacent, or distant, to an adenoma has not yet been investigated. Three biopsies from mucosae adjacent (20 cm, ipsilateral) and distant (contralateral) to an isolated tubular adenoma were analysed in 14 patients and 8 controls. Laser microdissection isolated stromal and epithelial crypt components, and quantitative RT-PCR analyses of uPA, uPAR, PAI-1 and PAI-2 mRNA levels were performed. Among controls, no significant differences in the markers were noted. With left colon isolated tubular adenoma, uPA, uPAR, and PAI-2 mRNA levels were significantly increased in the adjacent mucosal stroma compared to epithelial crypt levels (p < 0.05). In right colon adenoma, the mRNA levels of these 3 molecular markers were significantly increased only in the adjacent mucosal stromal samples (p < 0.05). Isolated tubular adenoma in the colon increases significantly the mRNA levels of 3 proteolysis-associated molecular markers in the stromal, but not in the epithelial, components of adjacent mucosa. These results suggest the presence of regional and dynamic interactions in apparently non-involved mucosae.