Expression of pro-inflammatory protein, iNOS, VEGF and COX-2 in oral squamous cell carcinoma (OSCC), relationship with angiogenesis and their clinico-pathological correlation.

One main etiology for oral squamous cell carcinoma (OSCC) is inflammation. Inducible nitric oxide synthase (iNOS), vascular endothelial growth factor (VEGF) and cyclooxygenase-2 (COX-2) are the important molecules showing close relation to not only inflammation but also carcinogenesis and angiogenesis. Angiogenesis is defined as the formation of new blood vessels from existing vasculature. It is necessary for tumor growth and progression and also involved in metastasis. The objective of this research was to study the expression and relationship among iNOS, VEGF, COX-2, angiogenesis and their clinico-pathological correlation in OSCC. In this study, standard indirect immunohistochemical technique using polyclonal antibodies specific to human iNOS, VEGF, COX-2 and CD31 was performed in formalin-fixed paraffin-embedded tissue sections of 66 OSCC samples. The staining patterns and intensity are measured and analyzed statistically. The results showed that epithelial components of squamous cell carcinomas demonstrated moderate to intense staining for iNOS, VEGF and COX-2. iNOS shows correlation with cervical lymph node metastasis and tumor staging (TNM) of the patients and angiogenesis. VEGF shows correlation with tumor grading, tumor staging and angiogenesis. COX-2 shows correlation with cervical lymph node metastasis. In conclusion, the expression of iNOS, VEGF and COX-2 exists in OSCC. The data provided show the expression of these chemical mediators associated with carcinogenesis and angiogenesis in OSCC. It can be the primary database before using angiogenesis drug against these mediators for OSCC treatment.

Sappayatosok K ，Maneerat Y ，Swasdison S ，Viriyavejakul P ，Dhanuthai K ，Zwang J ，Chaisri U ... -  《Medicina Oral Patologia Oral y Cirugia Bucal》

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》

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》

Microvessel density (MVD) and vascular endothelial growth factor expression (VEGF) in human oral squamous cell carcinoma.

Carcinogenesis is thought to be dependent on neovascularization. Vascular endothelial growth factor (VEGF) is a glycoprotein that has the capability of increasing vascular proliferation and permeability. VEGF has been found to be expressed in several different types of tumours and it may contribute to the progression of malignant tumours. Increased microvessel density (MVD) has been described in oral squamous cell carcinoma (OSCC) and seems to be related to patient prognosis. Fifty-two cases of OSCC were evaluated in the present study. Immunostaining for VEGF and Factor-VIII was performed. The MVD was evaluated in G1, G2 and G3 tumours. The differences between these 3 groups were statistically significant (p = 0.0331). MVD was also evaluated in lymph-node negative and lymph-node positive cases: the differences between these two groups were statistically significant (p < 0.0001). VEGF expression was evaluated in G1, G2 and G3 tumours. The differences between the 3 groups were not statistically significant (p = 0.289), even if an increasing trend in the VEGF positivity was evident from G1 to G3. The difference of VEGF expression between tumours with and without lymph node metastases was not significant (p = 0.196). No correlation was present between intensity of VEGF positivity and histological grading or lymph-node status and between VEGF and MVD. Our data showed that MVD was correlated with grading and lymph-node status, while no similar correlation was found for VEGF.

Artese L ，Rubini C ，Ferrero G ，Fioroni M ，Santinelli A ，Piattelli A ... -  《ANTICANCER RESEARCH》

Inducible nitric oxide synthase expression in various laryngeal lesions in relation to carcinogenesis, angiogenesis, and patients' prognosis.

The inducible nitric oxide synthase (iNOS) expression leading to vascular endothelial growth factor (VEGF) overexpression may be useful as a factor for predicting recurrence after initial treatment and prognosis in laryngeal squamous cell carcinoma (SCC). We analyzed expression of iNOS, p53, and VEGF in various laryngeal lesions. The study samples consisted of 63 SCC, 20 dysplasia, 7 polyp, and 5 normal epithelium of the larynx. The expression of iNOS, p53, and VEGF was identified by immunohistological methods. No positive immunostaining for iNOS, p53, and VEGF was observed in normal epithelium and polyps. In contrast, with the progression from mild/moderate dysplasia to severe dysplasia to carcinoma, their expression levels increased. In dysplasia, there was a significant positive correlation among expression of iNOS, p53, and VEGF. In SCC, iNOS expression correlated with VEGF overexpression and microvessel density, but not with p53 overexpression. In SCC, the expression of iNOS and VEGF significantly increased in patients who developed local recurrence and/or metastases after initial treatments. Kaplan-Meier analysis showed that disease-free survival was significantly shorter in patients with iNOS or VEGF expression. Multivariate analysis showed expression of iNOS and VEGF as independent indicators for poor disease-free survival.

Shigyo H ，Nonaka S ，Katada A ，Bandoh N ，Ogino T ，Katayama A ，Takahara M ，Hayashi T ，Harabuchi Y ... -  《ACTA OTO-LARYNGOLOGICA》