Vascular endothelial growth factor-C expression correlates with lymph node localization of human melanoma metastases.

Melanoma metastasizes by different mechanisms comprising direct invasion of the surrounding tissue and spreading via the lymphatic or vascular system. Despite their clinical relevance, the molecular mechanisms that guide the route of spreading and localization of the metastases in different tissues are not well known. Recent studies in different tumor types have shown that vascular endothelial growth factor-C (VEGF-C), which displays a high specificity for lymphatic endothelium, is involved in tumor-induced lymphangiogenesis and lymphatic metastatic spread. The authors studied the expression of VEGF-C in cultured human melanoma cells derived from cutaneous and lymph node metastases as well as in metastatic melanoma tissue specimens to assess a possible involvement of this growth factor in lymph node localization of melanoma metastases. VEGF-C expression was evaluated in vitro on human melanoma cell lines established from cutaneous and lymph node metastasis specimens by reverse transcriptase-polymerase chain reaction, Northern blot analysis, and immunofluorescence analysis. Immunohistochemical analysis of 42 tissue specimens of melanoma metastases and 10 tissue specimens of primary skin melanomas was also performed. Preferential expression of VEGF-C was detected in lymph node-derived tumor cell lines at both the mRNA and protein levels. The association between VEGF-C production and lymph node localization of metastases was confirmed by the in vivo analysis. In addition, analysis of 10 patients, from whom specimens of both the primary skin melanoma and melanoma metastases were available, indicated a correlation between VEGF-C expression in the primary tumor and lymph node localization of metastases. The findings of the current study demonstrate that VEGF-C expression is correlated with localization of melanoma metastases in the lymph nodes and suggest that VEGF-C expression in primary skin melanoma may be predictive of lymph node metastatic dissemination.

Schietroma C ，Cianfarani F ，Lacal PM ，Odorisio T ，Orecchia A ，Kanitakis J ，D'Atri S ，Failla CM ，Zambruno G ... -  《CANCER》

Quantification of vascular endothelial growth factor-C and its receptor-3 messenger RNA with real-time quantitative polymerase chain reaction as a predictor of lymph node metastasis in human colorectal cancer.

This study was undertaken to determine whether vascular endothelial growth factor-C (VEGF-C) and the expression of its receptor VEGF receptor-3 (VEGFR-3) are correlated with lymph node metastasis in human colorectal cancer and whether their expression levels might be used to predict lymph node metastasis. Fifty-three surgical specimens of colorectal cancer with (n = 24) or without (n = 29) lymph node metastasis were studied. The messenger RNA (mRNA) expression of VEGF-C and VEGFR-3 was quantified with a new method for kinetic quantitative polymerase chain reaction (PCR), real-time quantitative (RTQ) reverse transcriptase-PCR. In addition, their protein expressions were assessed immunohistochemically. The VEGF-C mRNA level in primary tumors correlated with VEGF-C protein expression, lymph node metastasis, and lymphatic invasion. Sixteen of 24 patients with lymph node metastasis showed VEGF-C mRNA overexpression. Morphologically, VEGF-C protein expression in primary tumors showed a statistically significant relationship with lymph node metastasis and lymphatic invasion. Real-time quantitative reverse transcriptase-PCR is a sensitive method for detection and quantification of VEGF-C and VEGFR-3 mRNA expression. Furthermore, the expression levels of VEGF-C mRNA and protein in colorectal cancer are correlated with lymph node metastasis and lymphatic invasion.

Kawakami M ，Furuhata T ，Kimura Y ，Yamaguchi K ，Hata F ，Sasaki K ，Hirata K ... -  《SURGERY》

Expression of vascular endothelial growth factors A, B, C, and D and their relationships to lymph node status in lung adenocarcinoma.

Vascular endothelial growth factors (VEGFs) C and D are novel members of the VEGF family that show some selectivity toward lymphatic endothelial cells. Recent studies suggest that VEGF-C may be involved in lymphangiogenesis and spread of cancer cells via lymphatic vessels. However, whether other VEGF family members play a role in lymph node metastasis is largely unknown. The aim of the present study was to explore whether expressions of VEGF-A, VEGF-B, VEGF-C, and VEGF-D are correlated with lymph node status in lung adenocarcinoma. Total RNA was isolated from 60 surgical specimens of lung adenocarcinoma with (n = 27) or without (n = 33) lymph node metastasis. The relative mRNA abundance of VEGF-A, VEGF-B, VEGF-C, and VEGF-D was measured by real-time reverse transcription-PCR analysis based on TaqMan fluorescence methodology. We found that, as single factors, expression of none of the four VEGF family members clearly correlated with the presence of lymph node metastasis. The only tendency noted was for higher VEGF-B and VEGF-C and lower VEGF-D levels in the node-positive group. However, two-way scatterplot analysis revealed that tumors with lymph node metastasis were associated with a pattern of low VEGF-D and high VEGF-A, VEGF-B, or VEGF-C, such that the ratios of VEGF-D:VEGF-A, VEGF-D:VEGF-B, or VEGF-D:VEGF-C were significantly lower in the node-positive group. Strikingly, none of the 11 tumors with high VEGF-D levels metastasized to lymph nodes. Furthermore, a low VEGF-D:VEGF-C ratio correlated with the presence of lymphatic invasion, and six of seven tumors with a pattern of very high expression of VEGF-C and low expression of VEGF-D displayed lymph vessel invasion that extended along the bronchovascular tree beyond the main tumor. Finally, levels of VEGF-A, but not VEGF-B or VEGF-C, were higher in tumors with large nodal metastasis (> or = 1 cm) than in those with small (< 1 cm) nodal metastasis. These results support the hypothesis that two VEGF family members are involved in lymph node metastasis at two distinct steps; VEGF-C facilitates entry of cancer cells into the lymph vasculature, whereas VEGF-A promotes the growth of metastatic tumor through angiogenesis. The results also suggest that the balance between VEGF-C and VEGF-D could be important rather than the level of VEGF-C alone. Whether a low VEGF-D level plays a causative role in lymph node metastasis requires further investigation.

Niki T ，Iba S ，Tokunou M ，Yamada T ，Matsuno Y ，Hirohashi S ... -  《CLINICAL CANCER RESEARCH》

Vascular endothelial growth factor C and vascular endothelial growth factor receptor 3 expression in squamous cell carcinomas of the head and neck.

VEGF proteins and their receptors are involved in tumor vessel neoformation. The third VEGF receptor, VEGFR3 (flt-4) is important during both blood vessel development and lymphatic vessel formation. Because HNSCC preferentially metastasizes to regional lymph nodes, we investigated the expression of VEGFR3 and its ligand VEGF-C in head and neck squamous cell carcinomas by semiquantitative RT-PCR (4 HNSCC cells lines and 6 HNSCC specimens) and by immunohistochemistry (18 HNSCC specimens). VEGFR3 protein expression was confirmed by Western blotting in four HNSCC cell lines and six HNSCC specimens. Semiquantitative mRNA analysis showed VEGF-C mRNA expression in three (SCC9, SCC25, LFFR) of four HNSCC cell lines and all six HNSCC specimens. VEGFR3 mRNA was found in two HNSCC cell lines (JPPA and SCC25) and only weakly detected in the other two HNSCC cell lines (SCC9 and LFFR). High amounts of VEGFR3 mRNA were shown in all six patients' tumor specimens. VEGFR3 Western blot analysis yielded a distinct band at the predicted size of 210 kD in JPPA and SCC9 and hardly detectable bands in SCC25 and LFFR cell lines. All six HNSCC specimens displayed strong VEGFR3 protein bands. Immunohistochemistry in 18 HNSCC specimens assigned strong to mediate VEGF-C IR and minor VEGFR3 IR to tumor cells and strong VEGF-C and VEGFR3 IR to tumor surrounding vessels. In addition, intense VEGF-C immunostaining was observed on perivascular and mononuclear cells in the tumor surrounding stroma. Subtyping of VEGFR3+ microvascular tumor vessels revealed partially double immunolabeling with CD34 and flk-1, indicating a common origin of blood and lymphatic vessels. The expression of VEGF-C on tumor cells could be correlated with recurrences, and larger primary tumors had more VEGF-C-positive vessels. The broad expression of VEGF C and VEGFR3 in HNSCC suggests involvement in tumor lymph angiogenesis and vascular angiogenesis, promoting tumor growth and propagation of cancer cells. This implies that inhibitors of lymph angiogenesis could become effective therapeutic options similar to classical angiogenesis inhibitors.

Neuchrist C ，Erovic BM ，Handisurya A ，Fischer MB ，Steiner GE ，Hollemann D ，Gedlicka C ，Saaristo A ，Burian M ... -  《HEAD AND NECK-JOURNAL FOR THE SCIENCES AND SPECIALTIES OF THE HEAD AND NECK》

Expression pattern of the lymphatic and vascular markers VEGFR-3 and CD31 does not predict regional lymph node metastasis in cutaneous melanoma.

Malignant melanoma of the skin preferentially metastasises via the lymphatic system. Novel molecular biomarkers, which are involved in malignant transformation, proliferation, angiogenesis and lymphangiogenesis, are currently under investigation to elucidate the risk for lymph node metastasis. To this end, the vascular endothelial growth factors VEGF-C and VEGF-D have been identified to promote lymphangiogenesis and lymphatic spread through activation of its receptor, Vascular endothelial growth factor receptor-3 (VEGFR-3). Prompted by this assumption, we estimated the degree of lymphangiogenesis by semiquantitative immunohistochemical analysis of the expression of VEGFR-3 and the panvascular marker CD31 in primary cutaneous melanoma (n=26) and correlated these findings with the sentinel lymph node (SLN) status. The cohort was selected for matched prognostic markers in SLN-positive and SLN-negative patients. In contrast to other studies, we observed an inverse correlation between expression of these markers with lymph node metastases. Additionally, no difference between intratumoral versus peritumoral CD31- or VEGFR-3 expression on blood vessels versus lymphatic capillaries could be detected. Interestingly, VEGFR-3 upregulation was not restrained to vascular structures but also appeared on tumor cells. In summary, in our series VEGFR-3/CD31 immunohistochemical staining of primary melanoma does not serve as a valid marker to predict lymph node involvement. As lymphatic spread is a complex, multi-step process, several different biomarkers have to be combined to define new prognostic subgroups in cutaneous melanoma.

Wobser M ，Siedel C ，Schrama D ，Bröcker EB ，Becker JC ，Vetter-Kauczok CS ... -  《ARCHIVES OF DERMATOLOGICAL RESEARCH》