ErbB2 overexpression correlates with increased expression of vascular endothelial growth factors A,C, and D in human breast carcinoma

BACKGROUND: The angiogenic factor vascular endothelial growth factor (VEGF)-A plays an important role in breast cancer progression. However, the involvement of VEGF-C and VEGF-D, two newer members of the VEGF family, in breast carcinoma and their relationship with clinicopathologic parameters have not been clearly demonstrated. METHODS: In this study, the expression levels of VEGF-A, VEGF-C, and VEGF-D protein in 107 breast carcinoma cases and 22 nonmalignant breast tissue samples were examined by immunohistochemistry and quantitated by image analysis. RESULTS: Higher expression of VEGF-C and VEGF-D was found in breast carcinomas than in nonmalignant breast tissue samples. Moreover, expression of VEGF-A, VEGF-C, and VEGF-D was significantly and positively correlated with ErbB2 expression. High levels of VEGF-A expression were associated with shorter disease-free survival (DFS). Patients with tumors expressing high levels of VEGF-C or VEGF-D showed a notable trend for worse DFS, however, it was not statistically significant. The combination of VEGF-A and VEGF-C status predicted survival better than either marker alone. CONCLUSIONS: Our study suggests that expression of the angiogenic and lymphangiogenic factors (i.e., VEGFs) might be regulated at least in part by ErbB2. In addition, the combination of VEGF-A and VEGF-C status may better predict prognosis of patients with breast carcinoma than VEGF-A alone.     

血管内皮生长因子D及其受体3在乳腺癌淋巴转移中作用的研究进展

乳腺癌是女性最常见的恶性肿瘤。乳腺癌淋巴转移与患者的预后密切相关。最近研究表明淋巴管生成可能会主动促进淋巴转移的发生,而血管内皮生长因子家族的部分成员在这一过程中发挥了重要作用,如血管内皮生长因子C、血管内皮生长因子D及其受体3等。但是,对乳腺癌中血管内皮生长因子D的作用及其预后价值、血管内皮生长因子受体3与乳腺癌淋巴管生成的关系等问题仍有争议。本文对近年国内外有关血管内皮生长因子D及其受体3在乳腺癌淋巴转移中作用的研究进展作一综述。     

Prognostic value of serum levels of interleukin 6 and of serum and plasma levels of vascular endothelial growth factor in hormone-refractory metastatic breast cancer patients

Prediction of survival for patients with metastatic breast cancer is often inaccurate and may be helped by new biological parameters. Tumour growth being angiogenesis-dependent, it has been hypothesised that the assessment of angiogenic factor production might reflect the clinical behaviour of cancer progression. This study was designed to investigate the clinical significance of vascular endothelial growth factor (VEGF) and interleukin 6 (IL-6) in hormone-refractory metastatic breast cancer. Serum and plasma concentrations of VEGF and serum concentration of IL-6 were measured in 87 patients with a fully documented history of metastatic breast cancer using an enzyme-linked immunoassay. All patients had detectable levels of VEGF, whereas 39% patients had detectable serum levels of IL-6. There was a positive correlation between IL-6 levels and the theoretical VEGF load of platelets (P<0.001). The presence of high levels of serum IL-6, but not VEGF, was significantly correlated to a shorter survival. In a multivariate analysis along with clinical prognostic parameters, serum IL-6 was identified as an independent adverse prognostic variable for overall survival (P&<0.001). These results indicate that serum IL-6 levels correlate to poor survival in patients with hormone-refractory metastatic breast cancer. Vascular endothelial growth factor serum and plasma levels are not useful indicators of prognosis for these patients.     

Vascular endothelial growth factor-D is an independent prognostic factor in epithelial ovarian carcinoma

We assessed the presence of vascular endothelial growth factor (VEGF)-C, VEGF-D and their receptor VEGFR-3 by immunohistochemistry in 59 epithelial ovarian carcinomas, 11 borderline tumours and 20 benign cystadenomas. VEGF-C and VEGF-D were generally expressed in tumour cells and also in endothelia adjacent to tumour nests which showed a strong staining for them. VEGFR-3 was expressed in lymphatic and vascular endothelial cells adjacent to tumour nests. Immunoreactivity was significantly more frequent as lesions progressed from a benign tumour to advanced carcinoma. A strong correlation was found between VEGF-C and VEGF-D detected in carcinoma and VEGFR-3 detected in neighbouring endothelial cells. Increased expression of VEGF-C, VEGF-D and VEGFR-3 was significantly associated with lymph node metastasis and peritoneal metastasis outside the pelvis. There was a significant correlation between the high levels of VEGF-C and VEGF-D proteins, and poor survival. The presence of VEGF-D was an independent prognostic indicator by multivariate analysis. We conclude that VEGF-C, VEGF-D and VEGFR-3 play an important role in lymphatic spread and intraperitoneal tumour development in ovarian carcinoma. Since VEGF-D was found to be an independent predictor of poor outcome, its measurement, together with other prognostic markers may improve prospective identification of patients with a poor prognosis.     

Enhancement of pleural dissemination and lymph node metastasis of intrathoracic lung cancer cells by vascular endothelial growth factors (VEGFs)

The expression of vascular endothelial growth factors (VEGFs) in tumors including lung cancer is considered to be associated with tumor development via capillary and lymph vessel neogenesis. Dissemination of the tumor cells to the pleura or regional lymph nodes is a critical poor prognostic factor for lung cancer patients. To investigate how VEGFs expressed in the intrathoracic infiltrating lung cancer cells participate in disease progression, we established stably VEGF-A-, VEGF-C-, VEGF-D-, VEGF-A and VEGF-C-, and VEGF-A and VEGF-D-expressing large cell lung cancer clones (TKB5/VEGF-A, TKB5/VEGF-C, TKB5/VEGF-D, TKB5/VEGF-A/C, and TKB5/VEGF-A/D), orthotopically inoculated these into the right thoracic cavity (i.t.) of nude mice, and evaluated the subsequent development of lung lesion, pleural effusion, pleural dissemination, and lymph node metastasis. While there were no significant differences either in culture or in subcutaneous tumor cell growth between the empty vector-transfected group (TKB5/empty) and each transfectant, the i.t. model demonstrated significantly different biological properties between the transfectants. TKB5/empty-inoculated mice frequently developed a large tumor on the pleura without pleural effusion, dissemination, or lymph node (LN) metastasis. In contrast, VEGF-A promoted a bloody pleural effusion (6/14), and VEGF-A and VEGF-D frequently generated pleural dissemination (11/14 and 9/11, respectively). Although both VEGF-C and VEGF-D generated LN metastasis (6/10 and 8/11, respectively), the locations of the metastasized LNs were quite different. TKB5/VEGF-C metastasized on the same side of axillary LNs as i.t. (right axillary LNs), whereas TKB5/VEGF-D metastasized to the mediastinal and left axillary and/or cervical LNs. Since the TKB5/VEGF-A/C or TKB5/VEGF-A/D co-transfectants revealed overlapping tumor progression patterns of VEGF-A and VEGF-C or VEGF-D, the metastatic LNs had abundant new capillaries and were larger than those of TKB5/VEGF-C or TKB5/VEGF-D-inoculated mice. Our results clearly demonstrate that VEGF-A secreted from intrathoracic lung cancer cells plays important roles in producing pleural effusion, dissemination, and capillary neogenesis, that VEGF-C is involved in LN metastasis, and VEGF-D in pleural dissemination and LN metastasis. It is most likely, however, that the mechanisms by which VEGF-C promotes LN metastasis are different from those of VEGF-D. The regulation of the expression of VEGFs in intrathoracic lung cancer cells might be a useful therapeutic approach to inhibiting tumor development and improving patient prognosis.     

Serum levels of VEGF-C, VEGF-D, and sVEGF-R2 in patients with lung cancer during chemotherapy

The aim of this study was to assess serum levels of vascular endothelial growth factor C and D (VEGF-C, VEGF-D) and soluble VEGF receptor 2 (sVEGFR-2) in patients with lung cancer during chemotherapy. The study included 80 patients (64 men and 16 women; mean age 61.1) diagnosed histologically with lung cancer. Forty-four (55%) had non-small cell lung cancer (NSCLC) and 36 (45%) had small cell lung cancer (SCLC). Squamous cell carcinoma was established in 56% (25 patients) of all patients with NSCLC, adenocarcinoma in 20% (9 patients), and non-small cell lung cancer in 23% (10 patients). The control group consisted of 20 healthy volunteers. Peripheral blood samples were taken before and after four cycles of chemotherapy. VEGF-C, VEGF-D, and sVEGFR-2 levels were assessed by ELISA method. Serum levels of VEGF-C and VEGF-D were significantly higher in both NSCLC and SCLC groups in comparison with controls. VEGF-C concentration decreased after chemotherapy, whereas VEGF-D concentration was at the same level. No correlation was found between VEGF-C and VEGF-D concentrations and the effect of treatment. Patients with lung cancer and progression after chemotherapy (PD) had the higher concentration of sVEGFR-2 than patients with partial remission (PR). The levels of sVEGFR-2 were lower before and after treatment than in controls. No relation was found between VEGF-C, VEGF-D, and sVEGFR-2 concentrations and the histological type and staging of lung cancer. Summing up, serum concentrations of VEGF-C and VEGF-D were higher in patients with lung cancer both before and after chemotherapy than in healthy controls, whereas sVEGFR-2 concentration was lower than in healthy controls. An increase in concentration of sVEGFR-2 during chemotherapy may suggest progression of the disease. However, it requires further examination.     

Pre-operative plasma levels of vascular endothelial growth factor A, C and D in patients with colorectal cancer

AimsVascular endothelial growth factor (VEGF)-C and VEGF-D are angiogenic and lymphangiogenic members of the VEGF family of growth factors. Increased VEGF-C or VEGF-D expression in human tumours may be associated with lymph-node metastasis and lymphatic invasion. Circulating plasma levels of VEGF-A, VEGF-C and VEGF-D were measured in patients with colorectal cancer, and assessed for their usefulness as a diagnostic tool for determining lymph-node metastasis.Materials and methodsOne hundred and twenty patients with colorectal cancer and 50 healthy control patients were included in the study. Plasma growth-factor levels were assessed by enzyme-linked immunosorbent assays.ResultsNo significant differences in plasma VEGF-C or VEGF-D levels were seen between patients subgrouped by clinicopathological variables. In particular, there were no differences in median plasma VEGF-C or VEGF-D level in patients with and without lymph-node involvement (VEGF-C: 11.2 U/ml [range, 4.9–51.9] vs 9.9 U/ml [4.4–93.4 U/ml]; P = 0.90; VEGF-D: 335 pg/ml [113–1102] vs 316.5 pg/ml [0–1343]; P = 0.68).ConclusionsCirculating plasma levels of VEGF-C and VEGF-D do not allow pre-operative identification of lymph-node status in patients with colorectal cancer.     

VEGF在恶性肿瘤中的研究进展

肿瘤的生长依赖肿瘤新生血管的形成，血管内皮生长因子（VEGF）及其家族是重要的血管生成正性调节因子，VEGF家族包括VEGF-A﹑VEGF-B ﹑VEGF-C﹑ VEGF-D ﹑VEGF-E和胎盘生长因子，本文旨在对VEGF家族的结构、功能、调控等方面的研究作一综述。     

Expression analysis of vascular endothelial growth factors and their relationships to lymph node metastasis in human colorectal cancer

This study was undertaken to determine whether expressions of the vascular endothelial growth factor (VEGF) family (VEGF-A, VEGF-B, VEGF-C, and VEGF-D) are correlated with clinicopathological parameters, with particular reference to lymph node metastasis in colorectal cancer. Total RNA was isolated from 82 surgical specimens of colorectal cancer and matched to normal mucosa with (n = 41) or without (n = 41) lymph node metastasis. The mRNA expression of each VEGF family member was quantified by real-time quantitative (RTQ) RT-PCR assay. VEGF-B and VEGF-C mRNA were significantly higher both in the tumors with lymph node metastasis (p = 0.027 and p = 0.024, respectively) and in tumors with lymphatic invasion (p = 0.042 and p = 0.005, respectively). In contrast, VEGF-D mRNA was down-regulated in tumors with lymphatic involvement (p = 0.047). Among the other clinicopathological factors, we noted that VEGF-A mRNA was higher in tumors with liver metastasis than in those without (p = 0.018) and was higher in tumors with venous invasion than in those without (p = 0.007). The results of this study demonstrate that high levels of VEGF-B, C and low levels of VEGF-D mRNA expression are associated with lymph node metastasis and lymphatic involvement. These results suggest that a balance among VEGF-B, VEGF-C, and VEGF-D might contribute to the lymphangiogenic process and metastasis in colorectal cancer.     

Vascular proliferation is important for clinical progress of endometrial cancer

Angiogenesis is essential for tumor growth, invasion, and metastatic spread. Whereas microvessel density (MVD) has been widely used as a measure of tumor-associated angiogenesis, we now wanted to examine the significance of other angiogenic markers, especially vascular proliferation (by Ki-67/factor VIII staining) and the degree of pericyte coverage [by alpha-smooth muscle actin (alpha-SMA)/factor VIII staining], in a large and population-based series of endometrial carcinoma with complete follow-up. Due to limited information on the role of lymphangiogenesis in these tumors, lymphatic vessel density (LVD) by LYVE-1 staining was also determined, as well as selected angiogenic factors [vascular endothelial growth factor (VEGF)-A, VEGF-C, VEGF-D and basic fibroblast growth factor (bFGF)], which could possibly be related to vascular proliferation and lymphangiogenesis. The information on angiogenic phenotype was related to clinicopathologic features and disease progress. Median vascular proliferation, as estimated by vascular proliferation index (VPI), was 3.9% and high VPI was associated with features of aggressive tumors and decreased survival. The prognostic effect of VPI was superior to that of MVD. Presence of pericyte coverage, as estimated by the alpha-SMA index (SMAI), was 35% and low SMAI was significantly associated with vascular invasion by tumor cells and impaired prognosis. Peritumoral lymphatic vessels (LVD-pt) were found in 39.5% of the cases and high LVD-pt was significantly associated with aggressive tumor features and decreased survival. In multivariate survival analysis, only the extent of vascular proliferation had independent prognostic effect, in addition to well-known clinicopathologic factors, whereas MVD did not have significant prognostic value. In conclusion, our study indicates that vascular proliferation is a meaningful variable in assessing the angiogenic phenotype of endometrial carcinoma.     

The VEGF signaling pathway in cancer: the road ahead

The vascular endothelial growth factor (VEGF) family of soluble protein growth factors consists of key mediators of angiogenesis and lymphangiogenesis in the context of tumor biology. The members of the family, VEGF-A (also known as VEGF), VEGF-B, VEGF-C, VEGF-D, and placenta growth factor (PlGF), play important roles in vascular biology in both normal physiology and pathology. The generation of a humanized neutralizing antibody to VEGF-A (bevacizumab, also known as Avastin) and the demonstration of its benefit in numerous human cancers have confirmed the merit of an anti-angiogenesis approach to cancer treatment and have validated the VEGF-A signaling pathway as a therapeutic target. Other members of the VEGF family are now being targeted, and their relevance to human cancer and the development of resistance to anti-VEGF-A treatment are being evaluated in the clinic. Here, we discuss the potential of targeting VEGF family members in the diagnosis and treatment of cancer.     

Serum vascular endothelial growth factor (VEGF) and interleukin-8 (IL-8) levels in small cell lung cancer

This study was conducted to determine the value of the angiogenic serum factors, vascular endothelial growth factor (VEGF) and interleukin-8 (IL-8), in patients with small cell lung cancer (SCLC). These serum angiogenic factors were measured of 34 SCLC patients on the before and after chemotherapy in comparison with 20 healthy controls using ELISA method. Serum levels of VEGF and IL-8 were significantly increased in SCLC patients compared with healthy controls (p < 0.001). No statistically significant relationships was found between investigated elevated serum angiogenic parameters and various characteristics of patients and disease such as disease stage and tumor burden. Likewise, we also found no correlation between serum angiogenic factors. Cytotoxic therapy of patients was accompanied by unchanged serum levels of angiogenic factors. Contrary to serum IL-8, elevated serum levels of VEGF was determined as a prognostic factor for survival by univariate analysis (p = 0.05). Multivariate analysis revealed that independent prognostic factors of overall survival included only response to chemotherapy and weight loss (p < 0.001 for both). In conclusion, our data suggest that the angiogenic serum factors, VEGF and IL-8, are useful diagnostic factors, but not predictive and prognostic markers for overall survival in SCLC patients.     

Lymph node metastasis as a new target for cancer treatment

The presence of lymph node metastasis is predictive of poor prognosis in solid tumors. Demonstration of specific markers of lymphatic endothelial cells has facilitated the study of the molecular mechanisms of metastasis, particularly lymphangiogenesis. The vascular endothelial growth factor (VEGF)-C/VEGF-D/VEGF receptor (VEGFR)-3 axis has been the most extensively studied, but other molecular pathways are also involved, such as fibroblast growth factor (FGF)-2, platelet-derived growth factor (PDGF)-BB, angiopoietin-1, VEGF-A, hepatocyte growth factor (HGF), insulin-like growth factor (IGF)-1 and -1R, and cyclooxygenase-2. Several strategies are currently being developed to prevent lymphatic metastasis, mainly targeting the VEGF-C/VEGF-D/VEGFR-3 axis: inhibiting maturation and activation of VEGF-C and VEGF-D by successive proteolyses, inhibiting binding of ligands to their receptor, and using tyrosine kinase inhibitors. Many questions remain and will be discussed in this article, particularly the role of lymph node metastasis in the development of visceral metastases, possible toxicities of antilymphangiogenic treatments, and their possible interactions with intratumoral penetration of other anticancer agents.     

Clinical significance of VEGF-A, -C and -D expression in esophageal malignancies

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.