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1.
目的:探讨MMP-2蛋白及MDM2蛋白在原发性胶质母细胞瘤和继发性胶质母细胞瘤中的表达差异性及其意义。方法:免疫组化SP二步法检测72例胶质母细胞瘤(36例原发性胶质母细胞瘤和36例继发性胶质母细胞瘤)石蜡包埋标本及10例正常脑组织石蜡包埋标本MMP-2蛋白和MDM2蛋白的表达情况,分析上述蛋白在两种病理类型的胶质母细胞瘤中的表达差异情况。结果:在原发性和继发性胶质瘤标本中,MMP-2蛋白的阳性表达率分别为63.9%和86.1%;MDM2蛋白的阳性表达率分别为61.1%和80.6%。MMP-2蛋白及MDM2蛋白在原发性和继发性胶质母细胞瘤中的表达差异存在统计学意义(P<0.05)。结论:MMP-2蛋白及MDM2蛋白在原发性、继发性胶质母细胞瘤中的表达差异可反映它们的不同分子遗传学特征。  相似文献   

2.
Circulating endothelial cells (CECs) as well as bone-marrow-derived endothelial precursor cells (EPC) play an important role in neovascularisation and tumour growth. To study the impact of neoadjuvant chemotherapy on the amounts of CEC and their precursor cells, mature CEC and their progenitors were quantified by flow cytometry in peripheral blood of breast cancer patients during anthracycline and/or taxane based neoadjuvant chemotherapy and subsequent surgery in comparison to age-matched healthy controls. Cell numbers were tested for correlation with serum levels of angiopoietin-2, erythropoietin, endostatin, endoglin, VEGF and sVCAM-1 as well as clinical and pathological features of breast cancer disease. Circulating endothelial cells were significantly elevated in breast cancer patients and decreased during chemotherapy, whereas EPC (CD34+/VEGFR-2+) as well as their progenitor cell population CD133+/CD34+ and the population of CD34+ stem cells increased. Concomitantly with the increase of progenitor cells an increase of VEGF, erythropoietin and angiopoietin-2 was observed. These data suggest that chemotherapy can only reduce the amounts of mature CEC, probably reflecting detached cells from tumour vessels, whereas the EPC and their progenitors are mobilised by chemotherapy. Since this mobilisation of EPC may contribute to tumour neovascularisation an early antiangiogenic therapy in combination with chemotherapy could be beneficial for the success of cancer therapy.  相似文献   

3.
Clinical significance of angiogenic factors in breast cancer   总被引:3,自引:0,他引:3  
Growth, progression, and metastasis of breast cancer, as well as of most of the other tumors, are angiogenesis-dependent processes.Several pro-angiogenic growth factors and endogenous inhibitors of angiogenesis have been identified and sequenced, and experimental studies suggest that angiogenic activity of a tumor may result from down-regulation of inhibitors of angiogenesis or up-regulation of endothelial growth factors. The mechanisms leading to the alteration of the balance between positive and negative modulators of angiogenesis are only partially known.We are at the beginning of research to identify the more active angiogenic factors in human breast cancer, and little information is presently available on their clinical significance. Preliminary results suggest that among the known angiogenic peptides, both vascular endothelial growth factor (VEGF) and platelet-derived endothelial cell growth factor / thymidine phosphorylase (PD-ECGF/TP) have promising prognostic and, perhaps, predictive value.No data are available on the clinical value of co-determination of positive and negative regulators of angiogenesis to look at the angiogenic balance of each single tumor. Only a few studies have assessed the role of endogenous inhibitors of angiogenesis in human breast cancer, with results available only on thrombospondin-1 and -2 (TSP-1, -2).Finally, the determination of some integrins such as 6 and v3 and of some other endothelial-adhesion molecules seems to be of potential prognostic value.Recognizing which are the more biologically active positive and negative angiogenic factors is the key for the identification not only of new prognostic markers but also of targets for antiangiogenic therapy in human breast cancer.  相似文献   

4.
血管生长因子与肿瘤血管生成   总被引:1,自引:0,他引:1  
血管生成对恶性肿瘤的发生、发展和预后至关重要。就血管内皮生长因子、血小板源性内皮细胞生长因子、碱性成纤维细胞生长因子等血管生成调节因子的研究进展进行综述 ,介绍了抗血管生成治疗肿瘤的现状和发展动向。  相似文献   

5.

Background:

Tumour-associated stroma has a critical role in tumour proliferation. Our aim was to determine a specific protein expression profile of stromal angiogenic cytokines and matrix metalloproteinases (MMPs) to identify potential biomarkers or new therapy targets.

Methods:

Frozen tissue of primary colorectal cancer (n=25), liver (n=25) and lung metastases (n=23) was laser-microdissected to obtain tumour epithelial cells and adjacent tumour-associated stroma. Protein expression of nine angiogenic cytokines and eight MMPs was analysed using a multiplex-based protein assay.

Results:

We found a differential expression of several MMPs and angiogenic cytokines in tumour cells compared with adjacent tumour stroma. Cluster analysis displayed a tumour-site-dependent stromal expression of MMPs and angiogenic cytokines. Univariate analysis identified stromal MMP-2 and MMP-3 in primary colorectal cancer, stromal MMP-1, -2, -3 and Angiopoietin-2 in lung metastases and stromal MMP-12 and VEGF in liver metastases as prognostic markers (P>0.05, respectively). Furthermore, stroma-derived Angiopoietin-2 proved to be an independent prognostic marker in colorectal lung metastases.

Conclusion:

Expression of MMPs and angiogenic cytokines in tumour cells and adjacent tumour stroma is dependent on the tumour site. Stroma-derived MMPs and angiogenic cytokines may be useful prognostic biomarkers. These data can be helpful to identify new agents for a targeted therapy in patients with colorectal cancer.  相似文献   

6.
Invasiveness in vitro and biological markers in human primary glioblastomas   总被引:2,自引:0,他引:2  
Invasion of spheroids from 20 human primary glioblastomas into precultured fetal rat brain tissue in culture has been studied and quantified. Between 30 and 98 percent of the normal brain tissue was destroyed by invading glioma cells within 4 days. The degree of invasion did not correlate with patient survival. A slightly higher invasiveness and shorter survival was seen in tumors with EGF receptor overexpression, and the opposite pattern was found for tumors with a TP53 mutation.The degree of invasiveness in vitro was far higher than would be expected from the dynamics of clinically observed tumor spread. This suggests that mechanisms suppressing invasion may be operative in the normal brain; alternatively the differences may be due to a higher permissiveness of the fetal brain tissue for invasion in vitro.  相似文献   

7.
Angiogenesis is the process of endothelial cell migration and proliferation induced by angiogenic factors, which is essential for the development of tumors. In recent years, studies have reported that SUMOylation acts on tumor angiogenesis by targeting angiogenic factors as one of post-translational modifications of proteins. Anti-angiogenic therapy is a new treatment method for tumor treatment following radiotherapy and chemotherapy, and it inhibits tumor growth by blocking tumor blood vessels. Therefore, SUMOylation may become a potential target for anti-angiogenesis therapy. This article focuses on the effect of SUMOylation on vascular growth factors, important signaling pathways proteins, and the migration and function of endothelial cells, in order to provide a new research idea for the anti-angiogenic therapy of tumors.  相似文献   

8.
BACKGROUND: To investigate the changes in angiogenic growth factor expression before and after gefitinib treatment, and the association between this expression and response to gefitinib treatment, we measured circulating levels of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), matrix metalloproteinase (MMP) -2 and -9, and tissue inhibitors of metalloproteinase (TIMP) -1 and -2 in patients with non-small cell lung cancer (NSCLC). METHODS: Serum and plasma samples were collected from 52 patients before and after gefitinib treatment. The levels of VEGF, bFGF, MMP-2, MMP-9, TIMP-1 and TIMP-2 were measured using a sandwich enzyme immunoassay kit. RESULTS: Of the 52 patients, 17 (32.7%) achieved a partial response, 19 (36.5%) had stable disease and 16 (30.8%) had progressive disease. The levels of VEGF, bFGF, MMP-2, MMP-9, TIMP-1 and TIMP-2 did not change significantly after gefitinib treatment, even in responders. The levels of VEGF in volunteers, responders and non-responders were 384 +/- 86.4, 404 +/- 94.3 and 719 +/- 99.8 pg/ml, respectively. The difference between volunteers and responders was not significant (P = 0.540), while the differences between volunteers and non-responders (P = 0.031), and responders and non-responders (P = 0.028) were significant. CONCLUSIONS: Although our results indicate that gefitinib treatment does not affect circulating levels of angiogenic growth factors even in patients who showed a response to gefitinib treatment, low levels of VEGF may predict response to gefitinib treatment in patients with NSCLC.  相似文献   

9.
BACKGROUND: Angiogenesis is required for growth and metastasis of colorectal cancer (CRC), and several positive regulators of tumor angiogenesis have been identified. Cyclooxygenase-2 (COX-2), known to be elevated in several human cancers, regulates angiogenesis by inducing angiogenic factors. The aim of this study was to clarify the levels and evaluate the relationships of COX-2, vascular endothelial growth factor A and C, thymidine phosphorylase (TP) and microvascular density (MVD) in paired tissue specimens between primary CRC and corresponding metastatic liver cancer. METHODS: Tissue samples from pairs of primary tumors and corresponding metastatic liver tumors from 44 patients with CRC were immunohistochemically evaluated for COX-2, VEGF-A, VEGF-C, TP and MVD. RESULTS: The primary and corresponding metastatic liver tumors tended to show concordant immunoreactivity for COX-2 (P = 0.005, rs = 0.428), VEGF-A (P = 0.039, rs = 0.314), TP (P = 0.005, rs = 0.422) and MVD (P = 0.046, rs = 0.304) by Spearman rank test. The rate of COX-2 immunoreactivity was higher in liver metastases than in primary tumors (P = 0.002), while the rate of VEGF-A was higher in primary tumors than in liver metastases (P = 0.0004). The incidence of TP immunoreactivity and the level of MVD did not differ between primary and metastatic liver tumors (P = 0.247; P = 0.229). Significant correlations were found between COX-2 immunoreactivity and VEGF-A immunoreactivity in metastatic liver tumors (P = 0.033) as well as in primary tumors (P = 0.008). CONCLUSION: The positive correlations between COX-2, VEGF-A, TP and MVD in primary CRC and liver metastasis as demonstrated here will help to predict the angiogenic activity of liver metastasis by analyzing primary tumors, allowing for individualized cancer treatment options.  相似文献   

10.
Since it has been widely recognised that renal cell carcinoma is refractory to standard therapies such as chemotherapy and radiotherapy, a new modality of treatment is needed. One of the potential alternative therapies for renal cell carcinoma may be inhibition of angiogenesis. In this study, we analysed the inhibitory effects of several potential agents on expression of angiogenic factors such as vascular endothelial growth factor and basic fibroblast growth factor, which are the main mediators in angiogenesis of renal cell carcinoma. We used medroxyprogesterone acetate, interferon-alpha, interferon-gamma, minocycline hydrochrolide and genistein, which are known to be antiangiogeneic. Northern blot analyses revealed that, among the five agents examined, genistein had a strong inhibitory effect on expression of vascular endothelial growth factor mRNA and basic fibroblast growth factor mRNA. Medroxyprogesterone acetate and interferon-alpha did not significantly decrease the level of either vascular endothelial growth factor mRNA or basic fibroblast growth factor mRNA. Interferon-gamma and minocycline had mild inhibitory effects on vascular endothelial growth factor mRNA and basic fibroblast growth factor mRNA expression. Genistein also inhibited both vascular endothelial growth factor mRNA and basic fibroblast growth factor mRNA expression after treatment with epidermal growth factor and hypoxia. These findings suggest that one of the mechanisms of the inhibition of angiogenesis by genistein is suppression of the expression of the angiogenic factors vascular endothelial growth factor and basic fibroblast growth factor in renal cell carcinoma.  相似文献   

11.

Background

Glioblastomas are primary malignant brain tumors with a dismal prognosis. Knowledge of growth rates and underlying growth dynamics is useful for understanding basic tumor biology, developing realistic tumor models, and planning treatment logistics.

Methods

By using repeated pretreatment contrast-enhanced T1-weighted MRI scans from 106 patients (aged 26–83 years), we studied the growth dynamics of untreated glioblastomas in vivo. Growth rates were calculated as specific growth rates and equivalent volume doubling times. The fit of different possible growth models was assessed using maximum likelihood estimations.

Results

There were large variations in growth rates between patients. The median specific growth rate of the tumors was 1.4% per day, and the equivalent volume doubling time was 49.6 days. Exploring 3 different tumor growth models showed similar statistical fit for a Gompertzian growth model and a linear radial growth model and worse fit for an exponential growth model. However, large tumors had significantly lower growth rates than smaller tumors, supporting the assumption that glioblastomas reach a plateau phase and thus exhibit Gompertzian growth.

Conclusion

Based on the fast growth rate of glioblastoma shown in this study, it is evident that poor treatment logistics will influence tumor size before surgery and can cause significant regrowth before adjuvant treatment. Since there is a known association between tumor volume, extent of surgical resection, and response to adjuvant therapy, it is likely that waiting times play a role in patient outcomes.  相似文献   

12.
Inhibition of angiogenesis by blocking angiogenic cytokines or their pathways has become a major target in experimental cancer therapies. This therapeutical approach requires a profound knowledge of growth factor profiles that contribute to tumor growth and progression. The respective knowledge is presently rather incomplete for head and neck squamous cell carcinomas (HNSCC). Therefore we studied expression of several angiogenic cytokines including VEGF, bFGF, PDGF-AB, PDGF-BB, G-CSF and GM-CSF in HNSCC in vivo and in vitro. In tumor tissues expression of all cytokines was observed albeit with marked differences concerning intensity and distribution pattern. Quantification of the cytokines in the supernatant of 15 tissue-corresponding HNSCC cultures revealed that VEGF, PDGF-AB and less frequently GM-CSF were secreted in high amounts of up to 13 ng/ml/10(6) cells. Twenty percent of the HNSCC cultures expressed only 1 cytokine in biologically active amounts, 60% 2 or 3 and 20% expressed the maximum of 4 cytokines simultaneously. Interestingly, we observed a distinct cytokine pattern: HNSCC cells secreting only 1 or 2 cytokines presented always with either VEGF and/or PDGF-AB, while G-CSF and GM-CSF were secreted primarily together with VEGF and PDGF-AB. The number of cytokines expressed by HNSCC cells correlated with the microvessel density of the original tumor and with the clinical outcome: tumors producing at least 3 cytokines revealed a significantly poorer patient prognosis. Our data indicate a major role for VEGF and PDGF-AB in HNSCC and that the additional secretion of G-CSF or GM-CSF might contribute to a poorer prognosis in patients suffering from these tumors.  相似文献   

13.
Angiogenesis, an essential step in the development of neoplasia, is a complex process that involves the interaction of tumor cells with stromal cells. Tumor-associated macrophages (TAMs) can participate in the induction of tumor angiogenesis and are thought to be of prognostic value in some neoplasms. We have investigated how macrophages contribute to angiogenesis in head-and-neck squamous-cell carcinoma (HNSCC) and have found that tumor cells attract monocytes and activate them to secrete angiogenic factors. The attraction of macrophages was due to the secretion of monocyte chemotactic protein-1 and TGF-beta1 by tumor cells, while tumor production of TGF-beta1 was responsible for activating macrophages. In addition, activated macrophages produced cytokines that acted in a paracrine fashion by secreting both TNF-alpha and IL-1, which in turn stimulated tumor cells to secrete increased levels of IL-8 and VEGF. These data demonstrate that TAMs play an important role in the in vivo induction of angiogenesis in HNSCC and suggest that anti-angiogenic therapies for HNSCC and perhaps other neoplasms must include strategies that will block the ability of tumor cells to recruit macrophages into the tumor micro-environment.  相似文献   

14.
15.
Mesenchymal stem cells (MSCs) are important components of stromal cell populations and serve a crucial role in tumor growth and progression. Previously, our laboratory successfully isolated and cultured MSCs from human glioma issues and demonstrated that glioma-associated mesenchymal stem cells (gb-MSCs) participate in and maintain tumor angiogenesis. Furthermore, growth factors, such as fibroblast growth factor and vascular endothelial cell growth factor, were demonstrated to be associated with endothelial cell tube formation. However, the effect of transforming growth factor β1 (TGF-β1) and platelet-derived growth factor-BB (PDGF-BB) on the angiogenic activity of gb-MSCs remains unknown. The present study aimed therefore to explore their effects in gb-MSCs angiogenesis. In the present study, gb-MSCs were isolated from patients with glioma and were characterized using flow cytometry and differentiation experiments. Furthermore, the results from tube formation assay revealed that TGF-β1 and PDGF-BB could mediate the angiogenic capacity of gb-MSCs in vitro. In addition, results from immunofluorescence demonstrated that gb-MSCs expressed TGF-β1R and PDGFR, which are the receptors for TGF-β1 and PDGF-BB, respectively. Taken together, these findings indicated that TGF-β1 and PDGF-BB may serve a crucial role in mediating gb-MSC angiogenesis, which might provide a therapeutic strategy for targeting the angiogenic capacity of gb-MSCs in patients with glioma.  相似文献   

16.
Summary A review of over 2000 patients who had estrogen receptors (ER) assayed in the primary breast carcinoma identified 48 cases in whom a subsequent second primary breast carcinoma or concurrent or recurrent secondary tumour had been tested for ER status. The relationship between the ER in the two specimens was as follows: Of 14 concurrent primary and secondary breast carcinomas the ER concentration was the same in 11 cases; in 1 case it was significantly higher in the primary tumour, in 2 others the reverse was observed. There was no major discordance in ER status. In 14 sequential carcinomas (after an average disease free time of 21 months), 12 pairs had identical ER status. There was major discordance of ER status in 2 cases where the secondary tumours contained ER while the primary carcinoma did not. The ER concentrations in the primary and the secondary carcinomas were comparable in 8 cases, while 3 and 5 cases had significantly higher or lower concentrations respectively in the sequential secondary tumour. In 20 cases where breast cancer developed in the contralateral breast (after an average disease-free interval of 27.7 months), essential concordance of ER status was observed in 15 of 20 sequential carcinomas. In 5 patients the first carcinoma was ER – and the second ER +; in one additional patient the first carcinoma was ER± and the second ER –. The ER concentrations differed significantly in 14 of the 20 bilateral carcinomas. The literature on estrogen receptor variation in breast carcinoma was reviewed.  相似文献   

17.
BACKGROUND AND OBJECTIVES: Angiogenic factors play a major role in tumor growth and metastasis. The purpose of this study was to clarify the prognostic significance of the expression of vascular endothelial growth factor (VEGF) and VEGF-C in gastric carcinoma. METHODS: Formalin-fixed and paraffin embedded sections of tumor tissue were obtained from 76 patients who underwent curative gastrectomy for gastric carcinoma. Immunohistochemical staining for VEGF and VEGF-C was performed. RESULTS: VEGF and VEGF-C were positively expressed in 39 and 45% of the patients, respectively. No correlation existed between VEGF and VEGF-C expressions. VEGF expression was significantly correlated with venous invasion. VEGF-C expression was significantly correlated with lymphatic and venous invasion. Patients with positive staining for VEGF showed a significantly lower survival rate than VEGF negative patients. After subdivision, according to the combination of VEGF and VEGF-C expression, VEGF-C expression had a significant unfavorable impact on prognosis among patients with negative staining for VEGF. The expression of VEGF and/or VEGF-C was independent prognostic determinant by the multivariate survival analysis. CONCLUSIONS: The positive expression for VEGF and/or VEGF-C was an important prognostic determinant after curative gastrectomy for gastric carcinoma. VEGF-C may stimulate the tumor progression in the absence of VEGF.  相似文献   

18.
The authors retrospectively analyse the results achieved in recent years by surgical treatment of 103 malignant primary or secondary liver cancers: (Three patients have been operated on twice at different times for recurrence.) 23 hepatic resections were performed for benign lesions. The operative mortality is very low, the incidence of postoperative complications is minimal, and the survival up to 8 years is rather satisfactory. In all cases we used Ton That Tung's surgical technique, that is, "finger fracture with intraparenchymal ligature of the vasculobiliary pedicles."  相似文献   

19.
Glioblastoma (GBM) is pathologically characterized by highly malignant neoplastic cells, focal necrosis and aberrant blood vessels composed of disorganized endothelial cells and pericytes. The recent cancer microarray database revealed upregulation of fibulin-7 (Fbln7), a member of the fibulin family, but provided no information on the tissue localization or biological function. In the present study, we demonstrated that Fbln7 is markedly overexpressed by the GBM tissue among astrocytic tumors, and immunolocalized mainly to endothelial cells and pericytes of the glomeruloid and hypertrophied microvessels. The production of Fbln7 by endothelial cells and pericytes was confirmed in cultured human umbilical vein endothelial cells (HUVEC) and human brain vascular pericytes (HBVP) and vascular endothelial growth factor (VEGF) stimulated the Fbln7 expression in HUVEC. Fbln7 bound to angiopoietin-1, but not angiopoietin-2 or Tie2 receptor, through interaction between the N-terminal portions of Fbln7 and angiopoietin-1, and it blocked phosphorylation of Tie2 receptor in HUVEC. In a coculture assay using HUVEC and HBVP, multilayered and irregular-shaped tube-like structures of HUVEC were induced by treatment with a high concentration of VEGF. This was accompanied by Fbln7 overproduction by HUVEC and angiopoietin-1 expression by HBVP. The production of aberrant VEGF-induced tube-like structures was attenuated by treatment with antibody or synthetic peptides specific to the Fbln7 N-terminal domain or knockdown of Fbln7. These data demonstrate that Fbln7 is overexpressed by endothelial cells and pericytes of the abnormal microvessels in GBM, and suggest that Fbln7 may contribute to the aberrant vessel formation by modulation of the angiopoietin-1/angiopoietin-2-Tie2 axis.  相似文献   

20.
Clinically, human glioblastoma (GBM) may develop de novo or from a low-grade glioma (secondary GBM), and molecular alterations in the two pathways may differ. This study examined the status of Survivin expression and apoptosis in 30 primary and 26 secondary GBMs. Our results show that cytoplasmic Survivin positivity was significantly (P<0.001) more frequent in primary GBMs (83%) than that in secondary GBMs (46%). In addition, an inverse correlation of cytoplasmc Survivin positivity with GBM apoptotic index, and a positive association between cytoplasmic Survivin and size of the tumours were observed. These results suggest that cytoplasmic Survivin, via its antiapoptotic function, may be involved in the tumorigenesis of many primary GBMs, but only in a small fraction of secondary GBMs. Furthermore, the overall progression times from low-grade precursor lesions to secondary GBMs were significantly shorter (P<0.05) in cytoplasmic Survivin-positive cases (mean, 15.6 months) than those in Survivin-negative cases (mean, 23.8 moths), and the positive expression level of Survivin in cytoplasm was upregulated in most secondary GBMs when compared to matched pre-existing low-graded lesions. These results suggest that the increased accumulation of Survivin in the cytoplasm of more malignant glioma cells may prove to be a selective advantage, thus accelerating progression to a more aggressive phenotype.  相似文献   

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