Hypoxia inducible factor-alpha expression correlates with vascular endothelial growth factor-C expression and lymphangiogenesis/angiogenesis in oral squamous cell carcinoma.

The number of blood vessels correlates with metastasis in solid tumors, including oral squamous cell carcinoma (OSCC). Hypoxia inducible factor-1alpha (HIF-1alpha) could play a role in tumor lymphangiogenesis by regulating the lymphatic expression of vascular endothelial growth factor-C (VEGF-C). HIF-1alpha protein expression, VEGF-C protein expression, lymphatic vessel density (LVD) and blood vessel density (BVD) in OSCC were investigated. HIF-1alpha and VEGF-C protein expression were investigated by means of immunohistochemistry in samples from 65 cases of OSCC. The density of the lymphatic microvessels and blood microvessels immunohistochemically stained by LYVE-1 and CD34 antibody, respectively, was calculated. The association between the HIF-1alpha expression and the clinicopathological parameters was evaluated. HIF-1alpha overexpression occurred in 43 out of the 65 tumor samples (66.2%), while VEGF-C overexpression was observed in 34 out of the 65 tumor samples (52.3%). Higher LVD was found in both high HIF-1alpha and high VEGF-C expression cases. HIF-1alpha overexpression was significantly correlated with VEGF-C overexpression (p = .018, Chi-square test), higher LVD (p < 0.001, Mann-Whitney U-test), and regional lymph nodal involvement (p = 0.004, Chi-square test) as well as UICC TMN classification (p = 0.043, Chi-square test), respectively. In addition, higher BVD existed in the high HIF-1alpha and VEGF-C expression groups (p < 0.001, Mann-Whitney U-test). HIF-1alpha might play a crucial role in regional lymph node metastasis as a regulator of lymphangiogenesis and angiogenesis in OSCC with a possible novel pathway involving VEGF-C. Therefore, HIF-1alpha might be a particularly promising target for controlling regional lymph node metastases by a combination of antiangiogenic and anti-lymphangiogenic effects in OSCC.

Liang X ，Yang D ，Hu J ，Hao X ，Gao J ，Mao Z ... -  《ANTICANCER RESEARCH》

Tumor lymphangiogenesis correlates with lymph node metastasis and clinicopathologic parameters in oral squamous cell carcinoma.

Lymphatic vessel density (LVD) and microvessel density (MVD) are important parameters for assessing the malignant potential of tumors and patient survival. In this report, the authors defined LVD as the density of D2-40-positive lymphatic vessels and MVD as the density of CD105-positive microvessels per unit area of tissue. It was reported previously that vascular endothelial growth factor C (VEGF-C) is a major modulator of LVD and MVD. The objectives of this study were to clarify the clinical and prognostic significance of both LVD and MVD in oral squamous cell carcinoma (OSCC) and to elucidate the lymphangiogenic and angiogenic activities of VEGF-C in cancer tissues. In total, 110 OSCC tissue samples were evaluated for LVD, MVD, and expression of VEGF-C using immunohistochemistry. Correlations among these parameters and clinicopathologic factors were examined. LVD was significantly higher in tumors that had very high expression of VEGF-C compared with tumors that had no/weak expression of VEGF-C. LVD correlated well with lymph node metastasis (P < .001). MVD was correlated significantly with positive lymph node metastasis (P < .001) but not with VEGF-C expression. In contrast, high expression of VEGF-C was correlated significantly with advanced tumor status (P = .041). Survival rates were lower in patients who had higher LVD (P < .001), higher MVD (P = .0028), and strong VEGF-C expression (P = .048). Lymphangiogenesis predominantly influenced metastasis-free survival. The current results suggested that LVD is a more useful tool than MVD and VEGF-C for deciding on therapeutic strategies in patients with OSCC.

Miyahara M ，Tanuma J ，Sugihara K ，Semba I ... -  《CANCER》

Hypoxia inducible factor-1alpha correlates with VEGF-C expression and lymphangiogenesis in breast cancer.

The transcription factor Hypoxia inducible factor-1alpha (HIF-1alpha) plays a crucial role in tumor progression by regulating angiogenesis, cell survival and drug resistance. HIF-1alpha is also implicated in biological functions under normoxic conditions and recent data provide evidence for a possible role in tumor lymphangiogenesis by regulating the lymphatic vascular endothelial growth factor-C (VEGF-C). In breast cancer, lymphatic vessel invasion (LVI) by tumor cells and subsequent metastasis to axillary lymph nodes is a critical point in progression of the disease with severe therapeutical and prognostic implications. Aim of this study is to investigate the role of HIF-1alpha in VEGF-C expression, lymphangiogenesis, and LVI in lymph node positive breast cancer. Lymphatic microvessel density (LMVD), LVI, HIF-1alpha and VEGF-C protein-expression were evaluated by immunohistochemistry in 119 cases of lymph node positive invasive breast cancer. There was a significant correlation between HIF-1alpha and VEGF-C (p = 0.026, r = 0.204, Spearman's coefficient of correlation). Further a significant association between HIF-1alpha-expression and the amount of peritumoral lymphangiogenesis LMVD was seen (p = 0.014, Mann-Whitney test). LMVD correlated significantly with LVI (p<0.001, Mann-Whitney test). HIF-1alpha was an independent prognostic factor for overall and disease free survival in uni- and multivariate analysis (p = 0.027, 0.029, 0.025, respectively, Cox regression). Our data provide evidence for a possible role of HIF-1alpha as regulator of tumor-associated lymphangiogenesis in human breast cancer and emphasizes the promising status of HIF-1alpha as a therapeutical target against tumor progression and metastasis.

Schoppmann SF ，Fenzl A ，Schindl M ，Bachleitner-Hofmann T ，Nagy K ，Gnant M ，Horvat R ，Jakesz R ，Birner P ... -  《BREAST CANCER RESEARCH AND TREATMENT》

Expression of endothelial nitric oxide synthase and vascular endothelial growth factor in oral squamous cell carcinoma: its correlation with angiogenesis and disease progression.

Angiogenesis is a crucial step in the successful growth, invasion, and metastasis of a tumor. It has been popularly accepted that vascular endothelial growth factor (VEGF) is the most potent angiogenic factor in tumor angiogenesis. As another possible star molecule responsible for tumor angiogenesis, the role of nitric oxide (NO) in tumor biology has gained much attention in recent years. The aim of this study was to investigate whether the expression of endothelial nitric oxide synthase (eNOS) and VEGF in oral squamous cell carcinoma (OSCC) is associated with angiogenesis. The present study also made a preliminary exploration of the possible cross-talking existing between eNOS and VEGF during tumor angiogenesis. In this study, expression of eNOS and VEGF were studied immunohistochemically in tissue sections from 40 patients with OSCC and 20 normal controls. To exclude eNOS antibody cross-reactivity with inducible or neuronal nitric oxide (iNOS or nNOS), eNOS expression was confirmed by using an eNOS mRNA in situ hybridization kit. The intratumoral microvessels were highlighted by immunostaining with anti-factor VIII-related antigen monoclonal antibody and counted as well-established methods. Then, chi-square test or Student's t-test was performed to study the correlations between the expression of eNOS and VEGF, microvessel density (MVD), and various clinicopathologic factors. Both eNOS and VEGF expression significantly increased in OSCC tissues, with a positive rate of 47.5% and 50%, respectively. The average MVD in OSCC tissues was 23.45 per high-power field (HPF), showing an obvious association with lymph node metastasis and clinical stages of patients with OSCC. Either eNOS or VEGF positivity was correlated with vessel involvement and OSCC progression. The mean MVD was significantly higher in eNOS- or VEGF-positive tumors than in eNOS- or VEGF-negative tumors. An obvious, correlation was also seen between eNOS and VEGF expression in OSCC tissues in this study. Overexpression of eNOS and VEGF might make an important contribution to the tumor angiogenesis in OSCC. NO generation by eNOS might be implicated in the VEGF-associated angiogenic process. Further investigation of the possible cross-talking between eNOS and VEGF with respect to tumor angiogenesis is necessary.

Shang ZJ ，Li JR 《JOURNAL OF ORAL PATHOLOGY & MEDICINE》

[Expression of hypoxia-inducible factor-1alpha and vessel endothelial growth factor in esophageal squamous cell carcinoma and clinico-pathological significance thereof].

To investigate the expression of hypoxia-inducible factor (HIF)-1alpha and vessel endothelial growth factor (VEGF) and their relations with the clinicopathological features of esophageal squamous cancer. Esophageal squamous cancer tissues and normal end squamous epithelium tissues were collected from 42 patients during operation. Real-time quantitative PCR was used to detect the mRNA expression of HIF-1alpha and VEGF and immunohistochemistry was used to detect the protein expression of HIF-1alpha and VEGF. The relations between the expression of HIF-1alpha, VEGF and depth of tumor invasion, histological grade, lymphatic invasion, and lymph node metastasis were evaluated. The HIF-1alpha mRNA expression level was 5.88 + 1.12 in the esophageal squamous cancer tissue, higher, but not significantly, than that in normal end squamous epithelium tissue 4.76 +/- 1.26 (P = 0.014). The VEGF mRNA expression level in the esophageal squamous cancer tissue was 12.79 +/- 2.51, higher, but not significantly, than that in the normal end squamous epithelium tissue (10.92 +/- 2.23, P = 0.010). The HIF-1alpha and VEGF protein positive rates in esophageal squamous cancer tissue were 50% (21/42) and 76% (32/42) respectively, significantly higher than those in the normal esophageal tissue [14% (6/42) and 33% (14/42) respectively, P = 0.001, P = 0.000]. The expression of HIF-1alpha mRNA and VEGF mRNA in the esophageal squamous cancer were correlated with lymph node metastasis (including lymphatic invasion) (P = 0.063 and P = 0.073 respectively). HIF-1alpha immunoreactivity was localized in the nucleus and/or cytoplasm of the cancer cells. The expression of HIF-1alpha protein was correlated with lymph node metastasis and histological grade (P = 0.013 and P = 0.028 respectively). No correlation was found between HIF-1alpha mRNA and VEGF protein. HIF-1alpha may be regulated at transcription and post-transcription levels in addition to protein level. It also plays an important role in lymphatic metastasis of esophageal squamous cancer and tumor malignancy degree. So HIF-1alpha and VEGF may serve as predictors of progression in esophageal squamous cell carcinoma and as potential targets for anti-angiogenesis therapy of esophageal squamous cell carcinoma.

Yu ZT ，Zhao HF ，Shang XB 《-》