Panayiotis A. Kyzas

Endoglin (CD105) is a proliferation-associated protein abundantly expressed in angiogenic endothelial cells. Recent studies revealed that CD105 is intensively expressed in tumor vasculature, whereas intratumoral microvessel density (MVD) determined with the use of antibodies to CD105 has been found to be an important prognostic indicator for the outcome in a number of malignancies. In the current study, we investigated endoglin expression and evaluated MVD in 108 patients with head and neck squamous cell carcinoma. Endoglin was intensively expressed in intratumoral blood vessels, whilst lymphatics were rarely positive for CD105. High microvessel density was associated with a more aggressive tumor phenotype, including advanced clinical stage (p=0.008) and the presence of lymph node metastasis at the time of diagnosis (p=0.02). When microvessel counts were assessed for their prognostic values (high vs low MVD), there was a statistically significant difference in the overall survival among patients with tumors of the oral cavity and larynx (pp=0.01). The prognostic impact of microvessel density was not dependent on clinical stage or lymph node status. The results of the current study suggest that CD105 is a promising target for tumor imaging and prognosis.

Dysadherin is a recently characterized cancer-associated cell membrane glycoprotein that has a crucial role to cell-cell adhesiveness. The aim of this study was to examine dysadherin expression in head and neck squamous cell carcinoma (HNSCC). A total of 108 tissue specimens of patients with HNSCC were examined using immunostaining for dysadherin, E-cadherin, and the specific lymphatic endothelium marker D2-40. We quantified dysadherin and E-cadherin expression, assessed intratumoral (ILD) and peritumoral lymphatic density (PLD), and examined the possible associations of all the above parameters with clinicopathologic features and outcome. Finally, we used double staining with dysadherin and D2-40 to examine the expression pattern of dysadherin simultaneously with the lymphovasculature environment of HNSCC. High dysadherin expression was correlated with higher clinical stage (χ², P = 0.01), with the presence of lymph node metastasis at the time of diagnosis (χ², P = 0.02), and with increased ILD (χ², P = 0.001). We observed an impressive reverse association between increased dysadherin expression and decreased E-cadherin expression (χ², P < 0.001). Surprisingly, dysadherin-positive cancer cells usually gathered around areas of high intratumoral lymphatic vessel concentration, surrounding and invading small intratumoral lymphatics. Higher clinical stage and increased dysadherin expression were found to be the only significant independent prognostic factors for overall survival (hazard ratio, 3.94; 95% confidence interval, 1.09-14.27 for clinical stage; hazard ratio, 3.92; 95% confidence interval, 1.46-10.51 for dysadherin). The loss of intercellular adhesiveness and increased dysadherin expression seems to be related to lymphangiogenesis in HNSCC, but this should be confirmed by additional studies. Dysadherin expression might be a promising prognostic marker for separation of patients at higher risk.

Estrogen receptor β (ERβ) is an important mediator of estrogen function in a variety of tissues. Its expression declines in breast, ovarian, prostatic and colon carcinomas as well as in astrocytic tumours. BAG-1 is a multifunctional protein with an important role in neoplasia and is possibly regulated by estrogen receptors. One of the direct targets of BAG-1 is HSP70. The purpose of this study was to analyse the expression pattern of these proteins in two distinct types of glial neoplasms, to investigate their possible correlation and probe their impact on prognosis. ERβ, BAG-1 and HSP70 protein expression was monitored immunohistochemically in 66 cases of astrocytomas and 20 oligodendrogliomas. In astrocytic tumours low ERβ expression correlated significantly with high grade (P < 0.001), higher expression of cytoplasmic BAG-1 (P < 0.001) and worse survival (log rank P = 0.02). Multivariate analysis revealed that ERβ expression had a prognostic value for overall survival in these patients (Cox P = 0.03), which was not dependent on grade. There was also statistically significant association of BAG-1 nuclear expression with HSP70 cytoplasmic expression. Our results strengthen the hypothesis that ERβ, BAG-1 and HSP70 play an important role in the pathogenesis and progression of glial neoplasms. Moreover, ERβ expression in astrocytic tumors might be an important prognostic factor for survival.

Purpose: Tumor angiogenesis is crucial for both the growth of the primary tumor and the development of metastases. Among the factors causing tumor angiogenesis, vascular endothelial growth factor (VEGF) is considered as a leading candidate. We aimed to assess the prognostic significance of VEGF and tumor angiogenesis in head and neck squamous cell carcinoma (HNSCC). Methods: We performed a retrospective study of 69 patients with HNSCC, in order to investigate whether VEGF immunohistochemical expression and tumor angiogenesis correlate with clinicopathological parameters and outcome. Tumor angiogenesis was estimated by determining microvessel density (MVD), and VEGF expression was assessed quantitatively. Results: Vascular endothelial growth factor and MVD correlated statistically significant with the clinical stage, but not with the presence of lymph node metastasis at the time of diagnosis. Tumors located in the oral cavity and larynx more often expressed high VEGF immunostaining compared with tumors located in the lower lip. High VEGF expression was associated with higher clinical stage and worse overall survival in this cohort of patients. Conclusions: Vascular endothelial growth factor expression may have prognostic significance for patients with HNSCC.

Lymph node metastasis is a frequent reason for adverse clinical outcome in many epithelial neoplasms, including head and neck squamous cell carcinoma. The mechanisms underlying the capability of epithelial neoplasms to metastasize via lymphatic vessels have not yet been fully elucidated. There is great debate about whether cancer cells can metastasize by expansion and invasion of pre‐existing peritumoral lymphatics or by the formation and invasion of new lymphatics within tumours (lymphangiogenesis). In order to investigate this issue, we examined 81 tissue specimens from patients with head and neck squamous cell carcinoma, using immunostaining for the specific lymphatic endothelium marker podoplanin, and assessed intratumoral and peritumoral lymphatic density. We also quantified lymphatic invasion and examined the possible associations of all the above parameters with clinicopathological features and outcome. Finally, we used double staining with podoplanin and the cell proliferation marker Ki‐67 in order to evaluate lymphangiogenesis. High intratumoral and peritumoral lymphatic density were both significantly associated with the presence of lymph node metastasis at the time of diagnosis (χ² test, p < 0.001 and p = 0.007, respectively) and there was a significant correlation between high intratumoral lymphatic density and lymphatic invasion. Patients with higher intratumoral lymphatic density exhibited shorter overall survival (log rank p < 0.001) and this correlation remained significant after multivariate analysis (Cox p = 0.04), indicating that intratumoral lymphatic density is an independent prognostic factor for mortality. Peritumoral lymphatic density had no influence on outcome. Double staining revealed the existence of proliferating intratumoral lymphatics, in which tumour emboli were occasionally observed. These results indicate that lymphangiogenesis indeed occurs in head and neck squamous cell carcinoma; that newly formed vessels are targets of invasion by cancer cells; and that intratumoral lymphatic density might be used as a criterion to separate patients at higher risk of an adverse clinical outcome. Copyright © 2005 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.