Vesnarinone inhibits angiogenesis and tumorigenicity of human oral squamous cell carcinoma cells by suppressing the expression of vascular endothelial growth factor and interleukin-8

Vesnarinone is a synthesized positive oral inotropic agent that has multiple biological activities on mammalian cells both in vitro and in vivo. This agent has been reported in relation to its antitumor effect with apoptosis-inducing activity. In the present study, we determined whether vesnarinone could suppress angiogenesis and growth of human oral squamous cell carcinoma cells in vitro and in vivo. Vesnarinone significantly inhibited the in vitro and in vivo expression of two major proangiogenic molecules, vascular endothelial growth factor (VEGF) and interleukin-8 (IL-8), in cultured cells and in cells implanted into the subcutaneous tissue of nude mice. Also, vesnarinone inhibited the nuclear factor-kappa B (NF-kappaB) activity in human oral squamous cell carcinoma cells in vitro. The decreased expression of VEGF and IL-8 correlated with decreased tumorigenicity and decreased vascularization of lesions in vivo. These findings suggest that vesnarinone can suppress the angiogenesis and growth of oral squamous cell carcinoma cells by inhibiting the expression of VEGF and IL-8 involved in blockade of NF-kappaB activity.     

口腔鳞癌组织中环氧化酶-2和血管内皮生长因子的表达及其相关性研究

目的:探讨环氧化酶-2(cyclooxyge-nase-2,COX-2)和血管内皮生长因子(vascularen-dothelialgrowthfactor,VEGF)在口腔鳞癌(oralsquamouscellcarcinoma,OSCC)组织中的表达及其相关性。方法:采用免疫组织化学SP法检测COX-2、VEGF在62例OSCC和10例口腔正常黏膜组织中的表达。结果:COX-2和VEGF在OSCC组织中的阳性表达率分别为100%(62/62)和61·3%(38/62),在正常黏膜组织中的阳性表达率均为0,两者差异有统计学意义,P<0·01。COX-2表达与OSCC的分化程度显著相关,P<0·01,但与肿瘤的大小、临床分期及淋巴结转移无相关性。VEGF表达与OSCC的临床分期及淋巴结转移显著相关,P<0·01,与肿瘤的大小、分化程度无相关性。OSCC中COX-2与VEGF的表达呈正相关,rs=0·353,P=0·005。结论:COX-2和VEGF在OSCC组织中呈高表达,并分别与鳞癌分化程度及临床分期相关,两者可作为防治OSCC的潜在靶点。     

Expression of vascular endothelial growth factor and prognosis of oral squamous cell carcinoma

The correlation between expression of vascular endothelial growth factor (VEGF) and prognosis for oral squamous cell carcinoma was investigated. Tissue samples of oral squamous cell carcinoma were obtained from 63 patients. Of these patients, 11 had stage I, 17 had stage II, 9 had stage III, and 26 had stage IV tumours. Immunohistochemical expression of VEGF was quantitatively determined by computer-assisted image analysis. The value of VEGF expression was significantly higher for the patients with poor prognosis than for those with good prognosis (P=0.0423). Regarding regional lymph node metastasis, VEGF showed no significant difference between metastasis positive and negative patients. Expression of VEGF may thus be a prognostic marker for oral squamous cell carcinoma.     

Association of preoperative radiation effect with tumor angiogenesis and vascular endothelial growth factor in oral squamous cell carcinoma.

This study examined the relationship between tumor angiogenesis and the radiation-induced response, evaluated based on pathological changes, in oral squamous cell carcinoma patients treated with preoperative radiation therapy. Forty-one cases of squamous cell carcinoma treated with preoperative radiation therapy were investigated. Tumor angiogenesis was assessed by scoring the intratumor microvessel density (IMVD). Expression of vascular endothelial growth factor (VEGF) was also evaluated before and after preoperative radiotherapy. There was no correlation between IMVD in the specimens before therapy and the pathological response to radiation therapy. However, radiation therapy decreased IMVD in the specimens after therapy. A significant association was observed between VEGF expression and resistance to radiation therapy: only 4 of the 21 patients whose tumors exhibited a high level (2 + or 3 + ) of VEGF staining experienced a major (3 + or 4 + ) pathological response to radiation therapy. Furthermore, an increasing level of VEGF expression after radiation therapy was observed in non-effective (0 to 2 + ) response cases. These results suggest that VEGF expression and the induction of this protein are related to radiosensitivity and could be used to predict the effects of preoperative radiation therapy on oral squamous cell carcinoma.     

S-1 inhibits tumorigenicity and angiogenesis of human oral squamous cell carcinoma cells by suppressing expression of phosphorylated Akt, vascular endothelial growth factor and fibroblast growth factor-2

It has been reported that S-1 can exert antitumor effects on various human cancers including oral squamous cell carcinoma (OSCC). However, little is known about the detailed mechanisms of the antitumor activity of S-1. In the present study, we determined whether S-1 could suppress the angiogenesis and growth of human OSCC cells in vitro and in vivo. The S-1 component (5-FU plus CDHP) significantly suppressed the growth and migration of OSCC cells and BAEC, which inhibited tubule formation in HUVECs in vitro. Also, S-1 inhibited the nuclear factor-kappaB (NF-kappaB) activity in human OSCC cells in vitro. Moreover, S-1 inhibited the expression of survival signal, phosphorylated Akt (p-Akt), and of two major proangiogenic molecules, vascular endothelial growth factor (VEGF) and fibroblast growth factor-2 (FGF-2), in cells implanted into the subcutaneous tissue of nude mice. The decreased expression of p-Akt, VEGF and FGF-2 correlated with decreased tumorigenicity and decreased vascularization of lesions in vivo. These findings suggest that S-1 can suppress the angiogenesis and growth of OSCC cells by inhibiting the expression of p-Akt, VEGF and FGF-2 involved in the blockade of Akt/NF-kappaB pathway.     

Simultaneous expression of furin and vascular endothelial growth factor in human oral tongue squamous cell carcinoma progression.

PURPOSE: Squamous cell carcinoma (SCC) of the tongue is a common malignancy of the oral cavity. Furin convertase activates several precursor matrix metalloproteinases involved in the degradation of the extracellular matrix. The pattern of expression of furin and vascular endothelial growth factor-C (VEGF-C), two key molecules in neoplasm development, was examined during the progression from normal epithelium to invasive SCC. EXPERIMENTAL DESIGN: We evaluated furin and VEGF-C expression and microvessel density (MVD) by immunohistochemistry in human tongue sections harboring normal epithelium, dysplastic epithelium, and/or SCC. Sections from 46 glossectomy specimens were assessed for furin expression. A selected group of 15 cases, each containing normal epithelium, precursor lesions, and invasive SCC, were further studied for furin and VEGF-C expression and MVD quantification. We also evaluated the pattern of furin expression and VEGF-C processing by Western blot analysis in three SCC cell lines with different degrees of aggressiveness. RESULTS: Furin and VEGF-C expression was notably higher in most precursor lesions and SCCs than in normal epithelia. Approximately 60% (n = 26) and 100% (n = 15) of the normal epithelia showed low-intensity staining for furin and VEGF-C, respectively. Intense staining for furin and VEGF-C was detected in approximately 80% (n = 34) and 100% (n = 15) of the SCCs, respectively. A significant correlation was seen between the expression of these two markers (Spearman's test, P < 0.00002). We found a statistically significant increase in MVD when either dysplasia (432 +/- 19.06; P < 0.05) or SCC (546 +/- 17.24) was compared with normal epithelium (315 +/- 17.27; P < 0.0001). SCC71, the most aggressive cell line analyzed, was the one with the highest furin expression. This cell line totally processed the VEGF-C proform, whereas the less aggressive line SCC9, exhibiting the least furin expression, did not. SCC15, of intermediate aggressiveness and furin expression, showed intermediate pro-VEGF-C processing. CONCLUSIONS: These findings suggest that furin is a useful marker of tumor progression and is responsible for VEGF-C processing. This in turn would enhance angiogenesis, leading to increased MVD associated with preinvasive and invasive neoplasia.     

Stem cell-like glioma cells promote tumor angiogenesis through vascular endothelial growth factor

Malignant gliomas are highly lethal cancers dependent on angiogenesis. Critical tumor subpopulations within gliomas share characteristics with neural stem cells. We examined the potential of stem cell-like glioma cells (SCLGC) to support tumor angiogenesis. SCLGC isolated from human glioblastoma biopsy specimens and xenografts potently generated tumors when implanted into the brains of immunocompromised mice, whereas non-SCLGC tumor cells isolated from only a few tumors formed secondary tumors when xenotransplanted. Tumors derived from SCLGC were morphologically distinguishable from non-SCLGC tumor populations by widespread tumor angiogenesis, necrosis, and hemorrhage. To determine a potential molecular mechanism for SCLGC in angiogenesis, we measured the expression of a panel of angiogenic factors secreted by SCLGC. In comparison with matched non-SCLGC populations, SCLGC consistently secreted markedly elevated levels of vascular endothelial growth factor (VEGF), which were further induced by hypoxia. In an in vitro model of angiogenesis, SCLGC-conditioned medium significantly increased endothelial cell migration and tube formation compared with non-SCLGC tumor cell-conditioned medium. The proangiogenic effects of glioma SCLGC on endothelial cells were specifically abolished by the anti-VEGF neutralizing antibody bevacizumab, which is in clinical use for cancer therapy. Furthermore, bevacizumab displayed potent antiangiogenic efficacy in vivo and suppressed growth of xenografts derived from SCLGC but limited efficacy against xenografts derived from a matched non-SCLGC population. Together these data indicate that stem cell-like tumor cells can be a crucial source of key angiogenic factors in cancers and that targeting proangiogenic factors from stem cell-like tumor populations may be critical for patient therapy.     

The role of vascular endothelial growth factor (VEGF) in oral dysplasia and oral squamous cell carcinoma

A better understanding of oral cancer pathogenesis is essential to improving patient prognosis and treatment modalities. Research has shown a significant increase in vascularity during the transition from normal oral mucosa, through differing degrees of dysplasia, to invasive carcinoma. A close association between tumour angiogenesis and tumour progression to late oral squamous cell carcinoma has also been reported. Vascular endothelial growth factor (VEGF) acts to induce endothelial proliferation, migration and specialisation in new and developing vascular beds. VEGF is also a promoter of angiogenesis in many tumour types, and has therefore been subject to numerous studies in oral dysplasia and squamous cell carcinomas. The contribution of VEGF to the development of oral dysplasia and invasive carcinomas is currently disputed due to conflicting results within the literature. More research is required before VEGF technology can be used to improve the diagnosis, prognosis and treatment of sufferers.     

VEGF及其受体KDR在非小细胞肺癌中的表达及与肿瘤血管形成关系

目的：探讨血管内皮生长因子（VEGF）及其受体（KDR）的表达与非小细胞肺癌（NSCLC）血管形成的关系。方法：分别应用免疫组织化学S-P法和原位分子杂交法检测62例NSCLC组织和16例肺的良性瘤样病变组织中的VEGF和KDR mRNA的表达，并对血管进行染色、计数。结果：62例肺癌组织中46例有VEGF的表达（占74．29％），阳性表达位于肿瘤细胞胞膜及胞质；KDR mRNA在49例中有阳性表达（占79．03％），阳性表达位于肿瘤血管内皮细胞、肿瘤细胞胞膜及胞质。VEGF和KDR mRNA的表达与有无淋巴结转移和临床病理分期密切相关；VEGF和KDR mRNA阳性表达组微血管密度明显高于阴性表达组，P〈0．01。结论：VEGF和KDR的表达与NSCLC的发生、发展和转移可能密切相关，可作为评估NSCLC患者预后的一项指标。     

VEGF及其受体KDR在非小细胞肺癌中的表达及与肿瘤血管形成关系

目的:探讨血管内皮生长因子(VEGF)及其受体(KDR)的表达与非小细胞肺癌(NSCLC)血管形成的关系。方法:分别应用免疫组织化学S-P法和原位分子杂交法检测62例NSCLC组织和16例肺的良性瘤样病变组织中的VEGF和KDRmRNA的表达,并对血管进行染色、计数。结果:62例肺癌组织中46例有VEGF的表达(占74·29%),阳性表达位于肿瘤细胞胞膜及胞质;KDR mRNA在49例中有阳性表达(占79·03%),阳性表达位于肿瘤血管内皮细胞、肿瘤细胞胞膜及胞质。VEGF和KDR mRNA的表达与有无淋巴结转移和临床病理分期密切相关;VEGF和KDR mRNA阳性表达组微血管密度明显高于阴性表达组,P<0·01。结论:VEGF和KDR的表达与NSCLC的发生、发展和转移可能密切相关,可作为评估NSCLC患者预后的一项指标。     

肾癌组织中血管内皮生长因子C的表达及血管生成的研究

目的研究肾癌组织(RCC)中血管内皮生长因子C(VEGF-C)的表达及微血管密度(MVD),探讨VEGF-C及MVD与肾癌生物学特征的联系。方法应用免疫组化S-P法,对53例肾癌及6例正常肾组织中VEGF-C进行检测,同时应用八因子抗体对肾癌组织中微血管进行染色,结合Meta-Morph显微荧光图像分析系统测定并分析53例肾癌中微血管密度,及其与VEGF-C和肾癌的病理分期、临床分级之间的关系。结果VEGF-C在正常肾组织呈阴性表达,在肾癌组织中呈不同程度的阳性表达,且过表达率在不同病理分级、临床分期组间有显著性差异(P<0.05)。MVD值在肾癌组织中不同病理分级、临床分期组间有显著性差异(P<0.05)。结论VEGF-C和MVD在肾癌组织中表达与肿瘤病理分级及临床分期密切相关,在肾癌浸润转移过程中起重要作用。     

Fibroblast growth factor receptor expression reflects cellular differentiation in human oral squamous carcinoma cell lines

This study examined the expression of fibroblast growth factor receptor 2 (FGFR 2) splice variants, IIIb and IIIc, in normal and malignant human oral keratinocytes and in normal oral fibroblasts by RT-PCR using both exon-specific primers and primers common to both FGFR 2 isoforms. Fibroblasts expressed exclusively FGFR 2/IIIc whilst the normal and malignant keratinocytes co-expressed FGFR 2/IIIb and FGFR 2/IIIc. Well- differentiated keratinocytes expressed proportionally more FGFR 2/IIIb than IIIc whereas the poorly-differentiated cells expressed more FGFR 2/IIIc than IIIb. The normal and malignant keratinocytes, but not fibroblasts, expressed an additional amplification product, which consisted of both IIIb and IIIc of FGFR 2 joined by an extra base pair and with the intronic sequence removed. The results indicate that the expression of FGFR 2 isoforms reflects the degree of cellular differentiation in normal and malignant human oral keratinocytes and that receptor complexes of FGFR 2/IIIb and IIIc may regulate ligand- receptor interactions.      

Prognostic significance of vascular endothelial growth factor protein levels in oral and oropharyngeal squamous cell carcinoma.

PURPOSE: Vascular Endothelial Growth Factor (VEGF) promotes angiogenesis in many different tumor types. VEGF levels may affect tumor growth, metastatic potential, and response to radiotherapy. This study assesses the prognostic value of VEGF protein levels in a cohort of patients with oral and oropharyngeal squamous cell carcinomas. The relationships between clinical outcome and the covariables of tumor-node-metastasis stage, disease stage (I to IV), grade, margin status, race, sex, and age were also determined. PATIENTS AND METHODS: Chart review identified 77 patients with oral or oropharyngeal squamous cell carcinoma treated with gross total surgical resection and postoperative radiation between 1981 and 1992. Sufficient follow-up data and tumor tissue were available in 56 patients (73%). VEGF protein levels were determined using immunohistochemistry. The association between VEGF status, covariables, and outcome was assessed in a bivariate and multivariate model using two-sided statistical tests. RESULTS: Twenty-three tumors (41%) were positive for VEGF expression. VEGF-positive tumors were more likely to recur locally (relative risk [RR] = 3.08; 95% confidence interval [CI], 1.03 to 9.24) and distantly (RR = 4.62; 95% CI, 1.41 to 15.10). In bivariate analysis, VEGF positivity was the most significant predictor of poor disease-free survival (RR = 2.66; 95% CI, 1.27 to 5.56) and overall survival (RR = 3.21; 95% CI, 1.63 to 6.32). In multivariate analysis, VEGF positivity was the most significant predictor of poor disease-free survival (RR = 2.75; 95% CI, 1.30 to 5.79) and overall survival (RR = 3.53; 95% CI, 1.75 to 7.13). CONCLUSION: In this cohort, VEGF positivity was the most significant predictor of poor prognosis. VEGF status may prove to be an important prognostic factor in head and neck cancer.     

The angiogenic "vascular endothelial growth factor/flk-1(KDR) receptor" pathway in patients with endometrial carcinoma: prognostic and therapeutic implications.

BACKGROUND: Vascular endothelial growth factor (VEGF) is an important endothelial cell mitogen associated with increased angiogenesis and aggressive tumor behavior. Its stimulating effect on endothelial cells basically is dependent on the presence of specific VEGF receptors, such as the flk-1(KDR) receptor. This study investigates the roles of VEGF and of a functionally intact angiogenic pathway, "VEGF/flk-1(KDR)," in patients with endometrial carcinoma and their significance in prognosis and therapy. METHODS: A series of 121 endometrial carcinomas were studied. The expression of VEGF by endometrial tumor cells was assessed using the monoclonal antibody (MoAb) VG1. VEGF/KDR complexes on tumor endothelium or activated microvessel density (aMVD) were identified using the MoAb 11B5. In addition, the standard microvessel density (sMVD) was assessed with anti-CD31. In all tumors, the alkaline phosphatase/antialkaline phosphatase technique was employed. A Fisher exact test or an unpaired, two-tailed t test was used for testing correlations between categoric tumor variables, whereas a log-rank test was used to determine statistical differences between life tables. A Cox proportional hazards model was used to assess the effect of tumor variables on overall survival. RESULTS: Cytoplasmic VEGF expression in > 50% of tumor cells was associated significantly with aMVD (P < 0.0001) and with sMVD (P < 0.003). In univariate survival analysis, VEGF (P = 0.0002), aMVD (P = 0.001), and sMVD (P = 0.0009) were significant prognostic variables. Equally important were the histologic parameters tumor type (P = 0.03), tumor grade (P = 0.003), and disease stage (P < 0.0001). In multivariate analysis, disease stage was the most important independent prognostic factor (P < 0.0001), followed by VEGF/KDR (P < 0.01), and VEGF (P < 0.04). Furthermore, VEGF and VEGF/KDR were the only independent prognostic variables for patients with Stage I endometrioid adenocarcinoma. CONCLUSIONS: sMVD and the angiogenic factor VEGF are important indicators of a poor prognosis in patients with endometrial carcinoma. VEGF/KDR complexes define a subgroup of patients with endometrial carcinoma with an even worse prognosis.     

Expression of hypoxia-inducible factor (HIF)-1alpha is associated with vascular endothelial growth factor expression and tumour angiogenesis in human oesophageal squamous cell carcinoma

The purpose of this study was to examine the relationship between hypoxia inducible factor (HIF)-1alpha expression, vascular endothelial growth factor (VEGF) expression, and tumour vascularity in squamous cell carcinoma of the oesophagus. Expression of HIF-1alpha and VEGF was examined in two oesophageal squamous cell carcinoma cell lines (TE2, TE3) and 82 archival surgical specimens of human oesophageal squamous cell carcinoma tissue. In both cell lines, the levels of HIF-1alpha protein and VEGF mRNA were increased under hypoxic conditions. Thirty-two of the 82 (39%) tumour specimens showed high levels of HIF-1alpha immunoreactivity in the nuclei and/or cytoplasm of cancer cells. HIF-1alpha expression correlated significantly with venous invasion, VEGF expression, and microvessel density. Among the 47 patients who did not receive pre-operative chemotherapy, the outcome of those with high HIF-1alpha-expressing tumours was significantly poorer than that of those with low HIF-1alpha-expressing tumours. These results suggest that HIF-1alpha and VEGF expression are important determinants of survival in squamous cell carcinoma of the oesophagus.     

蛋白酪氨酸磷酸酶基因、血管内皮生长因子在口腔鳞状细胞癌组织中的表达及意义

目的:探讨口腔鳞状细胞癌（OSCC）组织中的蛋白酪氨酸磷酸酶基因（PTEN）、血管内皮生长因子（VEGF）的表达及意义。方法:选取我院2015年4月至2017年9月获取的90例OSCC患者的肿瘤组织标本（OSCC组）和45例癌旁正常口腔黏膜组织标本（对照组）,采用免疫组织化学染色技术检测两组标本中PTEN蛋白、VEGF蛋白的表达情况,并分析不同病理学分级、临床分期、淋巴结转移的OSCC患者肿瘤组织中PTEN蛋白、VEGF蛋白阳性表达差异。结果:OSCC组标本中PTEN、VEGF蛋白阳性表达率分别为35.56%、75.56%,对照组标本中PTEN、VEGF蛋白阳性表达率分别为73.33%、31.11%,两组比较差异具有统计学意义（P＜0.05）;在Ⅲ期和Ⅳ期、低分化、发生淋巴结转移的OSCC患者组织中PTEN蛋白阳性表达率显著低于Ⅰ期和Ⅱ期、高分化和中分化、未发生淋巴结转移的OSCC患者,差异均具有统计学意义（P＜0.05）;在Ⅲ期和Ⅳ期、低分化、发生淋巴结转移的OSCC患者组织中VEGF蛋白阳性表达率显著高于Ⅰ期和Ⅱ期、高分化和中分化、未发生淋巴结转移的OSCC患者,差异均具有统计学意义（P＜0.05）。结论:OSCC组织中PTEN蛋白表达水平显著降低,VEGF蛋白表达水平显著升高,并且与肿瘤的发生发展关系密切。     

Combined analysis of vascular endothelial growth factor and platelet-derived endothelial cell growth factor expression in gastric carcinoma

Solid tumours require neovascularization for growth and metastasis. Both vascular endothelial growth factor (VEGF) and platelet-derived endothelial cell growth factor (PD-ECGF) are well-characterized inducers of angiogenesis. In this study we examined the expressions of these antigens and their relationship with microvessel density and also determined their prognostic significance. Ninety-five specimens resected from patients with gastric carcinoma were investigated using immunohistochemical methods. Microvessel density, determined by immunostaining for factor VIII-related antigen, was significantly higher in tumours that were both VEGF⁺ and PD-ECGF⁺ than in tumours that were both VEGF⁻ and PD-ECGF⁻. According to prognosis, patients with VEGF⁺ tumours had a significantly worse prognosis than did those with VEGF⁻ tumours. Although there was no significant correlation between PD-ECGF expression and prognosis, patients with PD-ECGF⁺ tumours tended to have a shorter survival than did those with PD-ECGF⁻ tumours. Moreover, the frequency of hepatic recurrence was significantly higher in patients with tumours that were both VEGF-positive and PD-ECGF⁺ than in all other patients. Int. J. Cancer 74:545–550, 1997. © 1997 Wiley-Liss, Inc.     

Cyclooxygenase-2 upregulates vascular endothelial growth factor expression and angiogenesis in human gastric carcinoma

Although gastric cancer with cyclooxygenase (COX)-2 overexpression is associated with poor prognosis, the mechanistic pathway remains unknown. We examined the associations between expressions of COX-2 and vascular endothelial growth factor (VEGF) in both gastric cancer cells and in human gastric cancer. The gastric cell line, Kato III, was transiently transfected with cox-2 expressing vector. The levels of COX-2, prostaglandin (PG) E2 and VEGF expression were measured post-transfection. Additionally, expressions of COX-2 and VEGF in human gastric cancer were determined by immunohistochemistry in archive gastrectomy specimens. Tumor angiogenesis was assessed by the microvessel density (MVD), which was determined by anti-CD34 immunostaining. Transient transfection of Kato III with cox-2 was associated with increased COX-2 expression, higher PGE2 production and upregulated VEGF expressions. Treatment with NS398, a specific COX-2 inhibitor, reduced VEGF expression in COX-2 expressing Kato III cells by 25%. Among the 67 gastric cancers examined, COX-2 overexpression was found in 45 (67%) cases whereas increased VEGF expression was detected in 46 (69%) cases. There was a significant association between COX-2 and VEGF expressions in gastric cancer (r=0.25, p=0.041). Additionally, tumor MVD was associated with both COX-2 (r=0.32, p=0.008) and VEGF (r=0.39, p=0.001) expressions. Our results showed that overexpression of COX-2 in both gastric cells and primary gastric cancer is associated with upregulation of VEGF and angiogenesis. Future studies should evaluate the potential anti-angiogenic effect of COX-2 inhibitors on human gastric cancer.