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1.
It has been demonstrated that vascular endothelial growth factor (VEGF) is associated with tumor progression as an angiogenic factor in esophageal squamous cell carcinoma (SCC)s. However, the role of other angiogenic factors such as transforming growth factor-alpha (TGF-alpha), platelet-derived endothelial cell growth factor (PD-ECGF), and basic fibroblast growth factor (bFGF) are still unknown in esophageal SCCs. In this study, we detected the expression of VEGF, TGF-alpha, PD-ECGF and bFGF in tissue specimens from 96 patients with SCC of the esophagus by immunohistochemical staining. To evaluate angiogenesis, endothelial cells were stained immunohistochemically and microvessel density (MVD) was counted in 24 cases. The positive rates for VEGF, TGF-alpha, PD-ECGF and bFGF were 65% (62/96), 67% (64/96), 66% (63/96), and 49% (47/96), respectively. Only TGF-alpha expression had a strong correlation with the average MVD (p=0.0059). However, the MVD increased as the number of positive factors for these 4 factors increased (p=0.0023). The expression of all of these factors significantly correlated to the depth of tumor invasion, and lymph node metastasis. Finally, survival analysis of the patients revealed that VEGF, TGF-alpha, and PD-ECGF were significant prognostic factors. However, multivariate analysis revealed that these factors were not prognostic. Thus, we suggest that TGF-alpha as well as VEGF, PD-ECGF and bFGF may be associated with angiogenesis, and the progression and metastasis of esophageal squamous cell carcinoma.  相似文献   

2.
The purpose of this study was to investigate the role of interactions between tumor cells and macrophages during angiogenesis in human gastric carcinomas. Macrophage infiltration into tumors and monocyte chemoattractant protein-1 (MCP-1) expression was assessed in 72 archival specimens of gastric carcinoma for comparison with tumor vascularity. The mRNA expression of MCP-1 was examined by RT-PCR in 6 gastric carcinoma cell lines and in fresh biopsy specimens from 18 patients. Immunolocalization of representative angiogenic factors, vascular endothelial growth factor (VEGF), and platelet-derived endothelial cell growth factor (PD-ECGF) was also done. MCP-1 expression in tumor cells increased with the depth of tumor invasion (Tis 9.5%, T1 19.4%, T2-4 60.0%), as did microvessel density and macrophage infiltration. Macrophage counts correlated with vessel counts, and both were significantly higher in MCP-1-positive than in negative tumors. Of the 6 gastric carcinoma cell lines, 2 constitutively expressed MCP-1 mRNA. In 6 (33.3%) of 18 biopsy samples, MCP-1 mRNA was expressed at higher levels in tumor tissues than in normal mucosa. VEGF protein was expressed by gastric carcinoma cells, whereas PD-ECGF protein was expressed mainly by stromal mononuclear cells. MCP-1 expression correlated significantly with VEGF but not PD-ECGF expression in gastric carcinomas. These results suggest that MCP-1 produced by human gastric carcinoma cells plays a role in angiogenesis via macrophage recruitment and activation.  相似文献   

3.
Rofstad EK  Halsør EF 《Cancer research》2000,60(17):4932-4938
Angiogenesis is a significant prognostic factor in melanoma, but the angiogenic factors controlling the neovascularization are not well defined. The purpose of this study was to investigate whether the angiogenesis and metastasis of melanoma are promoted by vascular endothelial growth factor (VEGF), interleukin 8 (IL-8), platelet-derived endothelial cell growth factor (PD-ECGF), and/or basic fibroblast growth factor (bFGF). Cells from human melanoma lines (A-07, D-12, R-18, and U-25) transplanted to BALB/c nu/nu mice were used as tumor models. Expression of angiogenic factors was studied by ELISA, Western blotting, and immunohistochemistry. Angiogenesis was assessed by using an intradermal angiogenesis assay. Lung colonization and spontaneous lung metastasis were determined after i.v. and intradermal inoculation of tumor cells, respectively. The specific roles of VEGF, IL-8, PD-ECGF, and bFGF in tumor angiogenesis, lung colonization, and spontaneous metastasis were assessed in mice treated with neutralizing antibody. The melanoma lines expressed multiple angiogenic factors, and each line showed a unique expression pattern. Multiple angiogenic factors promoted angiogenesis in the most angiogenic melanoma lines, whereas angiogenesis in the least angiogenic melanoma lines was possibly promoted solely by VEGF. Tumor growth, lung colonization, and spontaneous metastasis were controlled by the rate of angiogenesis and hence by the angiogenic factors promoting the angiogenesis. Lung colonization and spontaneous metastasis in A-07 were inhibited by treatment with neutralizing antibody against VEGF, IL-8, PD-ECGF, or bFGF. Each of these angiogenic factors may promote metastasis in melanoma, because inhibition of one of them could not be compensated for by the others. Our observations suggest that efficient antiangiogenic treatment of melanoma may require identification and blocking of common functional features of several angiogenic factors.  相似文献   

4.
Angiogenesis contributes to the growth and secondary spreading of solid tumors. Platelet-derived endothelial cell growth factor (PD-ECGF)/thymidine phosphorylase (TP) has been identified as such an angiogenic factor. In this study, the expression of PD-ECGF/TP and VEGF was evaluated by immunohistochemical staining of tumor specimens from 40 patients with cervical intraepithelial neoplasia (10 with moderate dysplasia; 10 with severe dysplasia; 10 with carcinoma in situ; 10 with invasive carcinoma). The microvessel density was assessed by immunostaining for factor VIII-related antigen in the most highly neovascularized area. In both the nucleus and cytoplasm, the intensity of PD-ECGF/TP expression in carcinoma in situ and invasive carcinoma was significantly stronger than that in moderate dysplasia. However, the intensity of VEGF expression was not significantly different in the various specimens. The microvessel density in mild dysplasia was significantly different from that in carcinoma in situ (p<0.05), and that in invasive carcinoma (p<0.05). There was no significant relationship between the microvessel density and the expression of PD-ECGF/TP or that of VEGF. These results show that the expression of PD-ECGF/TP appears to be involved in the promotion of angiogenesis in cervical intraepithelial neoplasia.  相似文献   

5.
Angiogenesis is an essential step in tumor growth and metastasis, but rather than being controlled by means of a simple mechanism, the control of tumor angiogenesis may be mediated by several angiogenic factors. We investigated the expression of basic fibroblast growth factor (b-FGF) and platelet-derived endothelial cell growth factor (PD-ECGF) in squamous cell carcinoma of the esophagus in order to clarify the mechanism of angiogenesis. Expression of b-FGF and PD-ECGF was immunohistochemically investigated in tissue specimens from the tumors of 79 patients with squamous cell carcinoma of the esophagus who underwent curative esophagectomy without preoperative chemotherapy or radiation therapy, and the relationship between expression of b-FGF/PD-ECGF, microvessel density (MVD), and clinicopathological background factors was assessed. Tumor cells that expressed b-FGF were found in 41 patients (51.9%), and tumor cells that expressed PD-ECGF were found in 57 patients (72.2%). Although the mean vascular density (47.9/mm(2)) of b-FGF-positive tumors was significantly lower than that (67.2/mm(2)) of b-FGF-negative tumors (p=0.014), the difference between the 56.0/mm2 in PD-ECGF-positive tumors and 60.3/mm2 in PD-ECGF-negative tumors was not significant. Although the survival rate of patients with b-FGF-positive tumors was significantly higher than those with b-FGF-negative tumors (p=0.033), there was no significant difference between the survival rates of patients with PD-ECGF-positive and -negative tumors (p=0.580). Expression of b-FGF may be associated with promotion of angiogenesis and a good prognostic factor in squamous cell carcinoma of the esophagus.  相似文献   

6.
Metastasis or progression of ovarian cancer cells is known to be due to the action of various angiogenic factors. We determined the expression of thymidine phosphorylase/platelet-derived endothelial cell growth factor (TP/PD-ECGF) and vascular endothelial growth factor (VEGF) in cell lines established from 3 serous adenocarcinomas, 3 clear cell carcinomas and 2 mucinous carcinomas of the human ovary. TP activity and the TP mRNA level were much higher in the serous adenocarcinoma cells than in the clear cells and mucinous carcinoma cells, and TP expression was extremely low in the clear cell carcinoma cells. Expression of VEGF mRNA was variable, but not significantly different between the 3 histological types of ovarian cancer. In vivo angiogenesis in the ovarian cancer cells was evaluated by the dorsal air sac assay and revealed that SHIN-3 and HRA serous adenocarcinoma cells, which have high levels of TP expression, induced angiogenesis, while KK clear cell carcinoma cells with low TP expression, did not. The degree of ovarian-cancer-induced angiogenesis seemed to be independent of expression of VEGF in the cells. To confirm that the serous adenocarcinoma-induced angiogenesis is dependent on TP levels, a potent and specific inhibitor of TP was administered orally to mice implanted with a chamber containing SHIN-3 or HRA cells. The TP inhibitor significantly inhibited the angiogenesis induced by the serous adenocarcinoma cells. These results suggest that the angiogenic potency of ovarian cancer cells differs with the histological type and is controlled by expression of TP/PD-ECGF, not by VEGF, and that TP-mediated angiogenesis may be the main factor responsible for progression or metastasis of ovarian serous adenocarcinomas.  相似文献   

7.
8.
 目的 研究食管癌iNOS、cNOS及VEGF表达 ,探讨NO作用双向性在食管癌发生、发展中的意义及其与VEGF的关系。方法 手术切除的食管鳞癌标本 75例 ,免疫组化法检测iNOS ,cNOS和VEGF活性表达及微血管计数 (MVD)。结果 iNOS、cNOS及VEGF阳性表达分别为 4 4 %、6 0 %及30 .7%。iNOS与组织学分级有关 ,即随着分化程度降低 ,iNOS活性越低 (P =0 .0 15 ) ;MVD在淋巴结转移者明显高于未转移者 (P =0 .0 0 3) ;iNOS与VEGF表达呈显著正相关 (P =0 .0 0 3) ;术后复发与组织学分级、iNOS表达缺失、MVD计数及淋巴结转移有关 (P值分别为 0 .0 0 3、0 .0 2 1、0 .0 4 1、0 .0 0 2 )。结论 i NOS在低分化型肿瘤的表达缺失 ,提示肿瘤预后不良。MVD计数及iNOS活性检测可作为食管癌预后判断的独立预测因素。  相似文献   

9.
Kleespies A  Bruns CJ  Jauch KW 《Onkologie》2005,28(5):281-288
Vascular endothelial growth factors (VEGF)-A, -C and -D are members of the proangiogenic VEGF family of glycoproteins. VEGF-A is known to be the most important angiogenic factor under physiological and pathological conditions, while VEGF-C and VEGF-D are implicated in the development and sprouting of lymphatic vessels, so called lymphangiogenesis. Local tumor progression, lymph node metastases and hematogenous tumor spread are important prognostic factors for esophageal carcinoma (EC), one of the most lethal malignancies throughout the world. We found solid evidence in the literature that VEGF expression contributes to tumor angiogenesis, tumor progression and lymph node metastasis in esophageal squamous cell carcinoma (SCC), and many authors could show a prognostic value for VEGF-assessment. In adenocarcinoma (AC) of the esophagus angiogenic properties are acquired in early stages, particularly in precancerous lesions like Barrett's dysplasia. However, VEGF expression fails to give prognostic information in AC of the esophagus. VEGF-C and -D were detected in SCC and dysplastic lesions, but not in normal mucosa of the esophagus. VEGF-C expression might be associated with lymphatic tumor invasion, lymph node metastases and advanced disease in esophageal SCC and AC. Therapeutic interference with VEGF signaling may prove to be a promising way of anti-angiogenic co-treatment in esophageal carcinoma. However, concrete clinical data are still pending.  相似文献   

10.
Thymidine phosphorylase in human esophageal squamous cell carcinoma   总被引:15,自引:0,他引:15  
BACKGROUND: Experimental evidence has shown that thymidine phosphorylase (dThdPase) is identical to platelet-derived endothelial cell growth factor (PD-ECGF) and has angiogenic activity. The enzymatic activity of dThdPase was needed for the angiogenesis by the enzyme. These observations were catalysts for the current study. METHODS: The authors examined retrospectively the expression of the angiogenic factor dThdPase in 163 primary esophageal squamous cell carcinomas and its association with angiogenesis and clinicopathologic findings. To determine whether dThdPase expression was a prognostic factor after adjustment for the established prognostic factors and microvessel count, the authors conducted a survival analysis using the Cox proportional hazards model. RESULTS: dThdPase was expressed significantly more frequently (P < 0.001) in esophageal carcinomas (83 of 163, 50.9%) than in adjacent nonneoplastic esophageal tissue samples (20 of 163, 12.3%). Microvessel counts were significantly higher (P < 0.001) in dThdPase positive carcinomas (18.3+/-6.2) than in dThdPase negative carcinomas (8.2+/-7.5). Significant correlations were observed between dThdPase expression and numerous clinicopathologic findings, including pT, pN, pM categories; lymphatic invasion; venous invasion; and residual tumors. Prognostic variables studied using a Cox hazard regression model confirmed that dThdPase expression was an independent prognostic factor in esophageal squamous cell carcinoma, although pN category was the best predictor of patient survival. CONCLUSIONS: This study indicated that in esophageal squamous cell carcinoma, dThdPase expression is associated with angiogenesis and is an unfavorable prognostic factor. These findings implied that the inhibition of dThdPase would improve the prognoses of some patients with dThdPase positive esophageal tumors.  相似文献   

11.
High microvessel density, an indirect measure of angiogenesis, has been shown to correlate with increased tumour size, lymph node involvement and poor prognosis in non-small-cell lung cancer (NSCLC). Tumour cell vascular endothelial growth factor (VEGF) and platelet-derived endothelial cell growth factor (PD-ECGF) expression correlate with angiogenesis and a poor outcome in this disease. In a retrospective study VEGF and PD-ECGF expression and microvessel density were evaluated immunohistochemically in surgically resected specimens (T1-3, N0-2) from 223 patients with operable NSCLC using the VG1, P-GF.44C and JC70 monoclonal antibodies respectively. High VEGF immunoreactivity was seen in 104 (46.6%) and PD-ECGF in 72 (32.3%) cases and both were associated with high vascular grade tumours (P= 0.009 and P= 0.05 respectively). Linear regression analysis revealed a weak positive correlation between VEGF and PD-ECGF expression in cancer cells (r= 0.21; P = 0.002). Co-expression of VEGF and PD-ECGF was not associated with a higher microvessel density than VEGF or PD-ECGF only expressing tumours. Furthermore a proportion of high vascular grade tumours expressed neither growth factor. Univariate analysis revealed tumour size, nodal status, microvessel density and VEGF and PD-ECGF expression as significant prognostic factors. Tumour size (P < 0.02) and microvessel density (P < 0.04) remained significant on multivariate analysis. In conclusion, VEGF and PD-ECGF are important angiogenic growth factors and have prognostic significance in NSCLC. Furthermore the study underlines the prognostic significance of microvessel density in operable NSCLC.  相似文献   

12.
13.
Angiogenesis in pancreatic ductal adenocarcinomas depends on the presence of angiogenic factors such as vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) and is thought to be stimulated by hypoxia. We tested the angiogenic potential of 9 cell lines of pancreatic ductal carcinoma origin by screening mRNA and protein expression of VEGF and bFGF and the release of VEGF into culture medium under normoxic and hypoxic (5% or 0.2% O2) conditions. Angiogenic activity was determined using 2- and 3-D endothelial cell assays. Furthermore, VEGF expression and tumor vascularization were studied in human pancreatic carcinoma tissues from orthotopic xenografts and resection specimens. All cell lines expressed (mRNA, protein) and secreted VEGF, whereas bFGF was only found in 3 cell lines and was secreted into the medium in low concentrations. In addition to the dominant isoforms VEGF121,VEGF165 and VEGF189, 2 isoforms described recently, VEGF145 and VEGF183, were detected. Severe hypoxia (0.2% O2), but not moderate hypoxia (5% O2) raised VEGF mRNA expression and protein secretion in 7/9 and 5/9 cell lines, respectively. Conditioned media from 7/9, 6/9, 8/9 and 7/9 cell lines stimulated endothelial cell proliferation under normoxic (24 and 48 hr) or hypoxic (24 hr, 0.2% and 48 hr 5% O2) conditions, respectively. Conditioned media from 4/9 cell lines also induced capillary-like sprouting under normoxic conditions and from 6/9 under hypoxic (0.2% O2) conditions. In xenografted carcinoma tissues microvessel density was found not to be increased around areas of ischemic necrosis. In resected ductal carcinomas showing tumor necrosis VEGF expression and microvessel density were only increased in 3/12 and 2/13 cases, respectively. In conclusion, in vitro most pancreatic ductal carcinomas show a distinct VEGF related angiogenic potential, as demonstrated by 2- and 3-D endothelial cell proliferation, which may be promoted by severe hypoxia. Surprisingly, perinecrotic tumor areas, which are supposed to be hypoxic, only rarely showed the expected increase in microvessel density and VEGF expression.  相似文献   

14.
The basic fibroblast growth factor (bFGF), the transforming growth factor (TGF)-beta 1, and the vascular endothelial growth factor (VEGF) expressions have been studied individually and in combinations with the factor 8-related antigen (F8RA) in relation to the microvascular density and prognosis of a pulmonary adenocarcinoma. The findings have revealed that the bFGF, TGF-beta 1 and VEGF expressions all correlated with microvascular density and the prognosis. A reduced expression of all three angiogenic factors correlated with-less tumor angiogenesis and a better prognosis. A multivariate analysis of the three prognostic factors also revealed that the the bFGF expression correlated with survival. These findings indicate that bFGF, TGF-beta 1, and VEGF expressions play important roles in tumor angiogenesis, and that the bFGF expression is a useful prognostic marker for assessing the outcome bf a pulmonary adenocarcinoma.  相似文献   

15.
李颖嘉  王东  高奉浔 《中国癌症杂志》2001,11(6):485-487,492
目的:研究人骨肉瘤细胞系OS-732血管生成相关作用。方法:应用鸡胚绒毛尿囊膜模型,通过解剖显微镜及透射电镜观察该细胞系促血管生成特点,并以免疫组化方法检测人骨肉瘤细胞系OS-732鸡胚绒毛尿囊膜移植瘤中血管内皮生长因子(vascular endothelial growth factor,VEGF),碱性成纤维细胞生长因子(Basic fibroblast growth factor,bFGF)的表达。结果:该细胞系具较强的诱导血管生成能力,解剖显微镜下可见血管辐辏现象,透射电镜下可见新生血管壁由单层内皮细胞构成,内皮细胞裂隙增宽,基底膜不完整,缺乏平滑肌成分,移植瘤组织发VEGF和bFGF均呈阳性表达,其中VEGF呈高表达。结论:肿瘤诱导的新生血管在病理,生理及形态功能方面都具有特征性,其诱导血管生成过程中可能有多种血管生长因子的共同参与,针对血管生长因子为靶点进行抗血管生成治疗对改善骨肉瘤预后可能具有重要意义。  相似文献   

16.
BACKGROUND: Thymidine phosphorylase (dThdPase) is identical to platelet-derived endothelial cell growth factor (PD-ECGF). dThdPase is known to promote the development of new blood vessels, which are fundamental to tumor growth and metastasis. Vascular endothelial growth factor (VEGF) is a 34-42 kilodalton (kD) protein that induces both angiogenesis and vascular permeability. Proliferating cell nuclear antigen (PCNA) is a 36 kD nuclear protein, and its expression is associated with DNA synthesis and cell proliferation. METHODS: The authors investigated the correlations of dThdPase and VEGF with the growth of head and neck squamous cell carcinoma (HNSCC) in 95 patients by examining PCNA expression as a marker of tumor proliferation. They also retrospectively examined the expression of dThdPase in primary HNSCC and its association with angiogenesis and clinicopathologic findings. RESULTS: Microvessel count was significantly correlated with the expression of VEGF (P = 0.046) but not with dThdPase expression. The expression of PCNA was significantly correlated with dThdPase (P < 0.001) but not VEGF expression. A significant correlation was found between VEGF and dThdPase expression (P = 0.003). Neither dThdPase nor VEGF correlated with clinicopathologic findings, except for the correlation between tumor location and VEGF expression (P 0.020). CONCLUSIONS: These findings suggest that VEGF is involved in angiogenesis in HNSCC. dThdPase may have effects on tumor growth other than angiogenic activity in HNSCC.  相似文献   

17.
Background The object of this study is to clarify the association of an angiogenic factor, PD-ECGF (platelet-derived endothelial cell growth factor/thymidine phosphorylase), with clinicopathologic factors, in this case tumor angiogenesis, in epithelial ovarian cancers. Methods Tumor specimens were obtained at the time of surgery from the primary lesion in 60 patients with epithelial ovarian cancer. Histologic cell types were assigned to tumors according to the World Health Organization classification: 26 were classified as serous adenocarcinoma, 15 as endometrioid adenocarcinoma, 9 as mucinous adenocarcinoma, 9 as clear cell carcinoma, and 1 as undifferentiated carcinoma. Surgical staging was based on the international Federation of Gynecology and Obstetrics (FIGO) staging system: 16 were stage I, 6 were stage II, 34 were stage III, and 4 were stage IV. Expression of PD-ECGF was evaluated by immunohistochemical staining. Microvessel density was assessed by immunostaining for factor VIII-related antigen in the most neovascularized area. Results Stroma cells stained more strongly than cancer cells (80% vs. 33%). The immunopositivity of PD-ECGF in stroma cells was higher in cases of advanced cancer. Expression of PD-ECGF in mucinous adenocarcinomas was significantly higher than that in serous adenocarcinomas, while PD-ECGF expression in clear cell carcinomas was significantly lower. The microvessel density in the cases with marked PD-ECGF-positive stroma cells was significantly higher than that in the cases with absent/minimal PD-ECGF-positive stroma cells (P<0.05). Conclusion The expression of PD-ECGF may play a crucial role in the promotion of angiogenesis in epithelial ovarian cancers.  相似文献   

18.
Neoangiogenesis is required for the growth of invasive lung carcinoma, however, the role of angiogenesis in the progression of premalignant changes to carcinoma of the lung is less clear. We have evaluated vascular endothelial growth factor (VEGF) expression and microvessel densities (MVDs) in 62 bronchoscopic biopsies from normal, reactive (basal cell hyperplasia (BCH)) and dysplastic bronchial epithelium and in tissue from twenty-seven invasive lung carcinomas in an effort to demonstrate angiogenic activity in these preneoplastic lesions and determine whether it is associated with increased bronchial epithelial VEGF expression. MVDs and VEGF RNA expression measured by quantitative RT-PCR were found to be elevated in comparison to normal bronchial tissue in bronchial dysplasias and invasive lung carcinomas but not in basal cell hyperplasias. Immunohistochemical (IHC) analyses revealed that expression of VEGF arose predominantly from bronchial epithelium. ELISA analysis of lung tumor tissue showed that elevated VEGF protein expression correlated with VEGF RNA levels (r=0.59, p=0.004). Increased expression of VEGF RNA was also found in histologically normal bronchial mucosa from patients with either dysplasia at other sites or a history of heavy tobacco use suggesting a possible field effect in regard to the elaboration of VEGF. Furthermore, analysis of VEGF isoforms and VEGF receptors by semi-quantitative RT-PCR in dysplastic and invasive lesions revealed characteristic altered patterns of expression in dysplasia and early cancer as compared to normal tissue. These results indicate that angiogenesis develops early in lung carcinogenesis and is associated with overexpression of VEGF.  相似文献   

19.
Angiogenesis contributes to the growth and secondary spreading of solid tumours. Platelet-derived endothelial cell growth factor (PD-ECGF) is identified as such an angiogenic factor. In the present study, the prognosis of the patients with high PD-ECGF uterine cervical cancers was worse than those with low PD-ECGF cancers, and PD-ECGF expression correlated with cellular proliferation and with vascular density and venous invasion in uterine cervical cancers. Therefore, PD-ECGF might contribute to the growth of uterine cervical cancers via angiogenesis related to vascular spreading. Furthermore, PD-ECGF and its mRNA had a wide range and were highly expressed in uterine cervical cancers, especially squamous cell carcinoma, regardless of clinical stage. Therefore, PD-ECGF in uterine cervical cancers might play a role of basic angiogenesis in all processes of advancing of uterine cervical cancers. This indicates that 5'-deoxy-5-fluorouridine might be highly effective in squamous cell carcinoma of the cervix, which possesses a high activity of thymidine phosphorylase to convert 5'-deoxy-5-fluorouridine to 5-fluorouracil, and that some angiogenic inhibitors of new capillary formation might be effective in the inhibition of tumour growth and spreading associated with angiogenesis.  相似文献   

20.
Angiogenesis is essential for tumour growth and metastasis. The induction of tumour vascularization is mediated by the release of angiogenic peptides. Among these factors, basic fibroblast growth factor (bFGF), vascular endothelial growth factor (VEGF) and matrix metalloproteinase-9 (MMP-9) are thought to be the most important. Previous experimental studies indicate that the process of apoptosis, the programme of cell death, may be related to angiogenesis in head and neck carcinogenesis. Therefore, cryostat sections of 49 head and neck squamous cell carcinomas (HNSCC) were investigated immunohistochemically for pro-apoptotic factors caspase-3 and Fas ligand (FasL) using a standard streptavidin-biotin complex procedure. Expression of bFGF, VEGF and MMP-9 served as angiogenic markers. Additionally, intratumoral microvascular density (MVD) was counted by immunostaining of endothelial cells using anti-vWF antibody. Comparing the expression of apoptotic and angiogenic factors, a statistically significant inverse correlation of caspase-3 expression and VEGF and MMP-9 expression was found. Concerning FasL, the correlation of its expression with expression of VEGF, bFGF and MMP-9 was inversely correlated. With respect to vWF-immunostaining, statistical analysis gave a clear inverse correlation between the tumour vascularity and the expression of FasL (p = 0.0008) and caspase-3 (p = 0.0068). Our results suggest that HNSCC tumour angiogenesis contributes to a reduction of apoptosis in tumour cells. This may be explained by the activation of pro-apoptotic factors caused by hypoxia.  相似文献   

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