Analyses of VEGFC/VEGF-D expressions, density and endothelial lymphatic proliferation in salivary gland neoplasms.

OBJECTIVE: The aim of this study was to assess vascular endothelial growth factor C (VEGF-C) and VEGF-D expressions, tumor lymphatic density (D2-40) and endothelial lymphatic proliferation (D2-40/Ki-67 double labeling) in a series of salivary gland neoplasm cases. MATERIALS AND METHODS: Twenty pleomorphic adenomas (PA), 20 adenoid cystic carcinomas (ACC) and 20 mucoepidermoid carcinomas (MEC) were assessed, as well as 10 normal minor salivary gland (SG) tissues for comparison. RESULTS: All cases presented positive VEGF-C expression in the peritumoral and intratumoral regions, and no differences in immunoexpression were detected between groups. However, the ACC group presented a significant difference in VEGF-C immunoexpression according to the predominant histological pattern. Most cases presented poor VEGF-D labeling in the peritumoral and intratumoral regions. Concerning peritumoral, intratumoral and total lymphatic endothelial density, the assessed groups revealed an increasing gradient, with lower values for PA, followed by MEC and ACC. CONCLUSION: No correlation was detected between VEGF-C and VEGF-D immunoexpression in relation to lymphatic tumor density and endothelial lymphatic proliferation. Western blotting (WB) revealed no difference between VEGF-C and VEGF-D expression among the lesions, corroborating the immunohistochemistry findings.

Over-expression of both VEGF-C and Twist predicts poor prognosis in human breast cancer.

BACKGROUND: Angiogenesis is an indispensable step in the growth and invasiveness of breast cancers involving a series of exquisite molecular steps. Pro-angiogenic factors, including vascular endothelial growth factor (VEGF), have been recognized as pivotal therapeutic targets in the treatment of breast cancer. More recently, a highly conserved transcription factor Twist has been reported to be involved in tumor angiogenesis and metastasis. METHODS: The expression of VEGF-C and Twist was immunohistochemically determined in tissue samples of primary tumors from 408 patients undergoing curative surgical resection for breast cancer. The correlations of VEGF-C and Twist expressions with clinicopathologic parameters as well as survival outcomes were evaluated. RESULTS: Of the 408 patients evaluated, approximately 70% had high expression of VEGF-C which was significantly associated with advanced tumor stages (P = 0.019). Similarly, VEGF-C expression was associated with the proliferation index Ki67, N3 lymph node metastasis, and D2-40-positive lymphatic vessel invasion (LVI) in a univariate analysis. Furthermore, patients with high expressions of VEGF-C and Twist (V + T+) had significantly increased lymph node metastasis, higher clinical stage, and worse disease-free survival, DFS (P = 0.001) and overall survival, OS (P = 0.011). CONCLUSIONS: Our results suggested that co-expression of VEGF-C and Twist was associated with larger tumor size, higher numbers of lymph node involvement, D2-40-positive LVI, higher risk of distant metastasis, and worse DFS or OS in breast cancer patients.

Correlation of intratumoral lymphatic microvessel density, vascular endothelial growth factor C and cell proliferation in salivary gland tumors.

Lymphatic dissemination is one of the most important pathways for metastasis in many solid tumors, including head and neck carcinomas. The lymphatic growth of cancer has been used as a significant independent adverse prognostic factor and provides information about tumor progression. Salivary gland tumors present different prognoses and have the ability to develop metastases; however, this information regarding the lymphatic spread is scarce. This paper quantifies the lymphatic microvessel density (LMD) in benign and malignant salivary gland tumors and analyzes the relationship between LMD and tumor expression of vascular endothelial growth factors C (VEGF-C) and the proliferative index. The results show that there is no correlation between LMD, VEGF-C and the proliferative index in the majority of salivary gland tumors analyzed, apart from polymorphous low-grade carcinoma which exhibits statistical correlation between LMD and the proliferative index (p < 0.05). This correlation probably does not indicate a poor prognosis for this PLGA, since this is a low metastasizing carcinoma of the salivary glands. Different from other solid tumors, such as breast or prostatic carcinomas, there is no correlation between VEGF-C and LMD in salivary gland tumors, and so these traits are not able to estimate the metastatic risk or the prognosis of these tumors.

Expressão de VEGF-C, VEGF-D, mensuração da densidade linfática e da proliferação endotelial linfática em neoplasias de glândulas salivar / Expression of VEGF-C, VEGF-D density measurement of lymphatic and lymphatic endothelial proliferation in salivary gland neoplasms

As neoplasias de glândulas salivares exibem uma grande diversidade morfológica e comportamentos biológicos variados o que suscita o interesse na pesquisa destas lesões. A disseminação das células tumorais é um passo inicial para a progressão de neoplasias malignas e, dentro deste contexto, os vasos linfáticos neoformados são considerados essenciais para que ocorra essa disseminação. O papel do VEGF (fator de crescimento endotelial vascular) na formação dos vasos é fato conhecido mas, pouco se sabe a respeito de sua participação em tumores de glândula salivar. Desta forma, o objetivo deste estudo foi avaliar a expressão do VEGF-C e VEGF-D, a densidade linfática tumoral (D2-40) e a proliferação endotelial linfática (dupla marcação D2-40/Ki-67) em uma série de neoplasias de glândulas salivares. A amostra foi composta por 20 adenomas pleomórficos, 20 carcinomas adenóides císticos, 20 carcinomas mucoepidermóides e 10 casos de tecido glandular salivar com características de normalidade para efeito comparativo. Todos os casos estudados exibiram expressão positiva para VEGF-C em região peritumoral e intratumoral, não sendo encontrada diferenças de imunoexpressão entre os grupos. No entanto, o grupo dos carcinomas adenóides císticos demonstrou diferença significativa da imunoexpressão do VEGF-C segundo o padrão cribriforme e sólido (p = 0,004). A maioria dos casos constantes do presente estudo, apresentou fraca marcação para VEGF-D em região peritumoral e intratumoral...

Salivary gland neoplasms exhibit a great morphological diversity and varied biological behavior which raises the interest in the study of these lesions. The spread of tumor cells is an early step in the progression of malignancies and the neoformed lymphatic vessels are considered essential in tumor dissemination. Vascular endotelial growth fator (VEGF) is a family of proteins involved in angiogenesis e lymphangiogenesis. However, in salivar tumors we have limited information on the expression. The aim of this study was to assess the expression of VEGF-C and VEGF-D, lymphatic vessel density (single-staining D2-40) and lymphatic endothelial proliferation (double labeling D2-40/Ki-67) in a series of salivary glands neoplasms. We selected 20 cases of pleomorphic adenoma, 20 of mucoepidermoide carcinoma, 20 of adenoid cystic carcinoma and 10 tissue sample of normal salivary gland. All cases studied showed positive expression of VEGF-C in intratumoral and peritumoral region, no differences in immunoreactivity was found between the groups. However, the group of adenoid cystic carcinoma showed a significant difference in immunoreactivity of VEGF-C by the cribriform and solid pattern (p = 0.004). Most of the cases included in this study showed weak immunoreactivity for VEGF-D in intratumoral and peritumoral region. In the assessment of lymphatic endotelial density peritumoral, intratumoral and total, the groups showed an increasing gradient, with lower values for the group of pleomorphic adenomas followed by mucoepidermoid carcinoma and adenoid cystic carcinoma. Lymphatic endothelial cell density was higher in malignant than benign tumors. No correlation was observed between the immunoreactivity of VEGF-C and VEGF-D in relation to tumor lymphatic density and lymphatic endothelial proliferation.

Promoting inflammatory lymphangiogenesis by vascular endothelial growth factor-C (VEGF-C) aggravated intestinal inflammation in mice with experimental acute colitis

Angiogenesis and lymphangiogenesis are thought to play a role in the pathogenesis of inflammatory bowel diseases (IBD). However, it is not understood if inflammatory lymphangiogenesis is a pathological consequence or a productive attempt to resolve the inflammation. This study investigated the effect of lymphangiogenesis on intestinal inflammation by overexpressing a lymphangiogenesis factor, vascular endothelial growth factor-C (VEGF-C), in a mouse model of acute colitis. Forty eight-week-old female C57BL/6 mice were treated with recombinant adenovirus overexpressing VEGF-C or with recombinant VEGF-C156S protein. Acute colitis was then established by exposing the mice to 5% dextran sodium sulfate (DSS) for 7 days. Mice were evaluated for disease activity index (DAI), colonic inflammatory changes, colon edema, microvessel density, lymphatic vessel density (LVD), and VEGFR-3mRNA expression in colon tissue. When acute colitis was induced in mice overexpressing VEGF-C, there was a significant increase in colonic epithelial damage, inflammatory edema, microvessel density, and neutrophil infiltration compared to control mice. These mice also exhibited increased lymphatic vessel density (73.0±3.9 vs 38.2±1.9, P<0.001) and lymphatic vessel size (1974.6±104.3 vs 1639.0±91.5, P<0.001) compared to control mice. Additionally, the expression of VEGFR-3 mRNA was significantly upregulated in VEGF-C156S mice compared to DSS-treated mice after induction of colitis (42.0±1.4 vs 3.5±0.4, P<0.001). Stimulation of lymphangiogenesis by VEGF-C during acute colitis promoted inflammatory lymphangiogenesis in the colon and aggravated intestinal inflammation. Inflammatory lymphangiogenesis may have pleiotropic effects at different stages of IBD.

DNA methylation regulates expression of VEGF-C, and S-adenosylmethionine is effective for VEGF-C methylation and for inhibiting cancer growth

DNA hypomethylation may activate oncogene transcription, thus promoting carcinogenesis and tumor development. S-adenosylmethionine (SAM) is a methyl donor in numerous methylation reactions and acts as an inhibitor of intracellular demethylase activity, which results in hypermethylation of DNA. The main objectives of this study were to determine whether DNA hypomethylation correlated with vascular endothelial growth factor-C (VEGF-C) expression, and the effect of SAM on VEGF-C methylation and gastric cancer growth inhibition. VEGF-C expression was assayed by Western blotting and RT-qPCR in gastric cancer cells, and by immunohistochemistry in tumor xenografts. VEGF-C methylation was assayed by bisulfite DNA sequencing. The effect of SAM on cell apoptosis was assayed by flow cytometry analyses and its effect on cancer growth was assessed in nude mice. The VEGF-C promoters of MGC-803, BGC-823, and SGC-7901 gastric cancer cells, which normally express VEGF-C, were nearly unmethylated. After SAM treatment, the VEGF-C promoters in these cells were highly methylated and VEGF-C expression was downregulated. SAM also significantly inhibited tumor growth in vitro and in vivo. DNA methylation regulates expression of VEGF-C. SAM can effectively induce VEGF-C methylation, reduce the expression of VEGF-C, and inhibit tumor growth. SAM has potential as a drug therapy to silence oncogenes and block the progression of gastric cancer.

Podoplanin and VEGF-C immunoexpression in oral squamous cell carcinomas: prognostic significance.

BACKGROUND: This study evaluated the clinical significance of podoplanin and vascular endothelial growth factor-C (VEGF-C) expression in oral squamous cell carcinoma (OSCC). PATIENTS AND METHODS: The immunohistochemical expression of podoplanin and VEGF-C were investigated in 42 well-differentiated OSCCs. The Chi-square test was used to analyze the association of biomarker expression with the clinical characteristics, treatment, and outcome, as well as with histopathological microscopic features and histopathological malignancy index. The relationship between podoplanin, VEGF-C and prognosis was also studied. Survival rates were calculated by the Kaplan Meier method. RESULTS: Strong podoplanin expression was associated with male gender (p=0.037) and with early clinical stage (I-II) (p=0.027). Strong podoplanin expression was more frequently found in patients with perineural infiltration. Podoplanin and VEGF-C expression were not significant prognostic factors for patients with OSCC. CONCLUSION: These results suggest that the strong podoplanin and VEGF-C expression by malignant cells is associated with perineural invasion in patients with OSCC.

Modulação da expressão de VEGF-C por mediador relacionado ao estresse em culturas de carcinomas espinocelulares de boca / Modulation of VEGF-C expression by stress related mediator in oral squamous cell carcinoma cell lines

Os mediadores do estresse, epinefrina e norepinefrina, participam da modulação de diversos processos celulares como a proliferação, a migração celular e a apoptose durante a tumorigênese, influenciando assim, o crescimento e a progressão tumoral. A presença de receptores beta-adrenérgicos e sua expressiva resposta ao estímulo do neurohormônio norepinefrina foram identificadas em várias linhagens de células tumorais, incluindo o carcinoma espinocelular de boca. O objetivo deste estudo foi investigar a influência da norepinefrina na expressão do fator de crescimento endotelial vascular do tipo C (VEGF-C) em cultura de células de carcinoma espinocelular de boca que continham receptores beta adrenérgicos. As linhagens celulares (SCC-9 e SCC-25) foram estimuladas com norepinefrina em diferentes concentrações (0,1; 1 e 10 M) e com 1M de propranolol, sendo analisadas após 1, 6 e 24 horas. A expressão gênica e proteica de VEGF-C foram avaliadas, respectivamente, por RT-PCR em tempo real e por ELISA. A produção de RNAm para VEGF-C teve um comportamento irregular, com tendências a variações da expressão gênica (aumento e inibição). A dosagem proteica nos sobrenadantes das culturas de células malignas não refletiu a expressão gênica de VEGF-C. Somente na linhagem SCC-25 ocorreu uma inibição significativa da produção de VEGF-C (p<0,001) pelas células neoplásicas no ensaio de 24 horas após o estímulo com 10M de norepinefrina. Estes resultados sugerem que a expressão de VEGF-C nas linhagens de carcinomas espinocelulares humanos de boca, parece não ser mediado pela norepinefrina, via receptores beta-adrenérgicos.

The mediators of stress, epinephrine and norepinephrine, are involved in modulation of many cellular processes such as proliferation, migration and apoptosis influencing the tumor growth and progression. The presence of beta-adrenergic receptors and their significant response to stimulation of neurohormone norepinephrine has been identified in various tumor cell lines, including oral squamous cell carcinoma. The aim of this study was to investigate the influence of norepinephrine on the expression of vascular endothelial growth factor type C (VEGF-C) in oral squamous carcinomas cell lines that contained beta-adrenergic receptors. Cell lines (SCC-9 and SCC-25) were stimulated with different concentrations of norepinephrine (0.1, 1 and 10 mM) and 1 M of propranolol, and analyzed after 1, 6 and 24 hours. Gene and protein expressions of VEGF-C were evaluated, respectively, by real time PCR and by ELISA. The results showed an irregular behavior of the oral squamous carcinoma cell lines, with trends to increase or to inhibit the VEGF-C gene expression. Dosage protein in supernatant cultures of malignant cells did not reflect the gene expression of VEGF-C. Only in the SCC-25 cell line was detected a significant inhibition of VEGF-C production by neoplastic cells, twenty-four hours after stimulation with 10M norepinephrine (p<0,001). These results suggest that VEGF-C expression in oral squamous carcinomas cell lines seems not to be mediated by norepinephrine through the beta adrenergic receptor pathway.