Stromal inflammatory cells are associated with poorer prognosis in primary cutaneous melanoma

We observed that non-tumor-infiltrating inflammatory cells are often present in the stroma of melanoma. The role of these stromal inflammatory cells (SIC) in cancer has not been studied. We evaluated the prognostic significance of SIC in 299 patients with vertical growth phase primary melanomas with at least 10 years of clinical follow-up. Lymphatic density and lymphatic invasion in the areas with SIC was quantified. The prognostic significance of these factors was evaluated using univariable and multivariable Cox models for melanoma-specific death and the time to first recurrence. Of the 299 melanomas, 161 exhibited areas with SIC. Percentages of vertical growth phase tumor-infiltrating lymphocytes and radial growth phase regression were significantly higher in cases with SIC compared to those without SIC (P = .005); lymphatic invasion was also detected more frequently in cases with SIC (P = .001). Lymphatic density in SIC areas was higher than that in other areas of the melanomas. Patients with SIC had poorer clinical outcome. Vascular endothelial growth factor-C (VEGFC) staining in a subset of these melanoma patients showed that VEGFC expression in the stromal macrophages was associated with lymphatic invasion in SIC areas. In conclusion, SIC in melanoma is associated with poorer prognosis, and the prognostic effect is partially mediated through induction of lymphangiogenesis with increased lymphatic invasion.

Podoplanin Expression Correlates with Disease Progression in Mycosis Fungoides

The aim of this study was to investigate the role of lymphangiogenesis in the clinical progression and outcome of mycosis fungoides. Immunohistochemistry and Western blot techniques were used to assess the expression of podoplanin and vascular endothelial growth factor C in mycosis fungoides. Expression of vascular endothelial growth factor C measured by immunohistochemistry was significantly higher in mycosis fungoides samples in comparison with control cases (chronic benign dermatoses) (p = 0.0012). Increased expression of podoplanin was found in advanced vs. early mycosis fungoides (p < 0.0001), and was positively correlated with cutaneous and nodal involvement (p < 0.001, p < 0.0001; respectively). Higher podoplanin expression was also significantly associated with shorter survival (p < 0.001). Strong positive correlation was observed between expression of podoplanin analysed by immunohistochemistry and Western blot (r = 0.75, p < 0.0001). A similar association was shown regarding expression of vascular endothelial growth factor C (r = 0.68, p = 0.0007). In conclusion, these results suggest that increased expression of podoplanin is associated with poor clinical course, as well as shorter survival, of patients with mycosis fungoides.

Src/STAT3 signaling pathways are involved in KAI1-induced downregulation of VEGF-C expression in pancreatic cancer

A previous study by our group demonstrated that overexpression of KAI1 was associated with lymphatic metastasis in pancreatic cancer. The present study further investigated the signaling pathways involved in KAI1‑induced downregulation of vascular endothelial growth factor C (VEGF‑C) and lymphatic metastasis in pancreatic cancer. Immunohistochemistry was performed to examine KAI1 and VEGF‑C expression in 28 surgically resected pancreatic cancer tissues. MIA PaCa‑2 and PCAN1 pancreatic cancer cell lines were transfected with KAI1 overexpression vector. VEGF‑C expression as well as phosphorylation of Src and signal transducer and activator of transcription (STAT)3 were assessed by western blot analysis. Furthermore, the signal transduction inhibitors PP2 and AG490 were used to block the Src and STAT3 signaling pathways, respectively. KAI1 was negatively correlated with VEGF‑C expression in pancreatic tumor samples. In MIA PaCa‑2 cells, VEGF‑C expression was more significantly inhibited by restoration of KAI1 than that in PCAN1 cells. In addition, Src and STAT3 phosphorylation was decreased by KAI1 in MIA PaCa‑2 cells. Of note, pre‑treatment with PP2 efficiently reversed the KAI1-induced enhancement of Src and STAT3 phosphorylation as well as VEGF‑C expression. Pre‑treatment with AG490 efficiently reversed the KAI1-induced enhancement of STAT3 phosphorylation and VEGF‑C expression, but had no effect on the upregulation of Src phosphorylation. The present study identified the involvement of Src/STAT3 signaling pathways in KAI1‑induced downregulation of VEGF‑C expression and suggested the implication of these pathways in lymphatic metastasis of pancreatic cancer.

Resistive-Pulse Measurements with Nanopipettes: Detection of Vascular Endothelial Growth Factor C (VEGF-C) Using Antibody-Decorated Nanoparticles

Quartz nanopipettes have recently been employed for resistive-pulse sensing of Au nanoparticles (AuNP) and nanoparticles with bound antibodies. The analytical signal in such experiments is the change in ionic current caused by the nanoparticle translocation through the pipette orifice. This paper describes resistive-pulse detection of cancer biomarker (Vascular Endothelial Growth Factor-C, VEGF-C) through the use of antibody-modified AuNPs and nanopipettes. The main challenge was to differentiate between AuNPs with attached antibodies for VEGF-C and antigen-conjugated particles. The zeta-potentials of these types of particles are not very different, and, therefore, carefully chosen pipettes with well-characterized geometry were necessary for selective detection of VEGF-C.

Expression of CD44v3, erythropoietin and VEGF-C in gastric adenocarcinomas: correlations with clinicopathological features

AIMS

To investigate the expression of CD44v3 and vascular endothelial growth factor C (VEGF-C) in gastric adenocarcinoma and the correlation with erythropoietin (EPO) and clinicopathological features.

METHODS

The expression of CD44v3, VEGF-C and EPO was evaluated by immunohistochemical staining in 169 gastric adenocarcinomas. The correlations between these parameters and patients' clinicopathological features were analyzed statistically.

RESULTS

CD44v3 and VEGF-C were positive in 50 (29.6%) and 82 (48.5%) patients, respectively. High CD44v3 expression was associated with poor cellular differentiation, extensive lymph node metastasis and advanced stage of gastric adenocarcinoma (P <0.05). High VEGF-C expression was significantly correlated with Lauren type, extensive lymph node metastasis and advanced stage of gastric adenocarcinoma (P <0.05). Univariate analysis of survival demonstrated that patients with a strong CD44v3 immunoreaction had a significantly worse overall survival compared with patients showing a weak CD44v3 immunoreaction (log-rank test: P = 0.0449). The mean survival time of patients with low CD44v3 expression was 30.6 months, which was much longer than the 21.6 months in patients with high expression. In addition, a strong association between immunohistochemical expression of CD44v3 and EPO was noted.

CONCLUSION

Increased expression of CD44v3 and VEGF-C may play a significant role in the carcinogenesis and progression of gastric adenocarcinoma. High CD44v3 expression may be a predictor of poor prognosis in gastric adenocarcinoma patients. We infer that some mechanisms may exist in regulating the expression of CD44v3 and EPO.

Intratumoral lymphangiogenesis and prognostic significance of VEGFC expression in gastric cancer

AIM

Vascular endothelial growth factor C (VEGFC) is thought to promote lymphangiogenesis in various human cancer tissues.

MATERIALS AND METHODS

The present study analyzed data from 72 patients with gastric cancer. The lymphatic vessel density (LVD) was determined by immunohistochemical staining using a monoclonal antibody (mAb) against D2-40, and the expression of VEGFC was investigated using a mAb against VEGFC.

RESULTS

The intratumoral LVD was higher in cases with nodal metastasis. The VEGFC-positive cases had a higher intratumoral LVD and were more invasive to the lymphatic vessels or lymph nodes than negative cases. Patients with VEGFC-positive cancer had significantly lower survival than those with negative cancer (p<0.05).

CONCLUSION

The expression of VEGFC was related to intratumoral lymph angiogenesis and serves as a pertinent predictive factor for lymphatic invasion or metastasis, while also providing prognostic value.

EMP1 regulates caspase-9 and VEGFC expression and suppresses prostate cancer cell proliferation and invasion

This study aimed to analyze the expression, clinical significance of f epithelial membrane protejn-1 (EMP-1) in prostate carcinoma, and the biological effect in its cell line by EMP1 overexpression. Immunohistochemistry and Western blot were used to analyze EMP1 protein expression in 76 cases of prostate cancer and 34 cases of normal tissues to study the relationship between EMP1 expression and clinical factors. EMP1 lentiviral vector and empty vector were respectively transfected into prostate cancer PC-3 cell line. Quantitative real-time reverse transcription polymerase chain reaction and Western blot were used to detect the mRNA level and protein of EMP1. 3-[4,5-Dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide assay, migration, and invasion assays were also conducted as to the influence of the upregulated expression of EMP1 that might be found on PC-3 cell biological effect. Immunohistochemistry: The level of EMP1 protein expression was found to be significantly lower in prostate cancer tissue than normal tissues (P < 0.05). Western blot: The relative amount of EMP1 protein in prostate cancer tissue was found to be significantly lower than in normal tissues (P < 0.05). The level of EMP1 protein expression was not correlated with age and prostate-specific antigen (PSA) concentration (P > 0.05), but it was correlated with T stages, lymph node metastasis, clinic stage, and Gleason score (P < 0.05). The result of biological function shown that PC-3 cell transfected EMP1 had a lower survival fraction, higher cell apoptosis, significant decrease in migration and invasion, higher caspase-9, and lower VEGFC protein expression compared with PC-3 cell untransfected EMP1 (P < 0.05). EMP1 expression decreased in prostate cancer and correlated significantly T stages, lymph node metastasis, clinic stage, and Gleason score, suggesting that EMP1 may play important roles as a negative regulator to prostate cancer PC-3 cell by regulating the expression of regulation of caspase-9 and VEGFC protein.

Prognostic significance of vascular endothelial growth factor expression in esophageal carcinoma: a meta-analysis

PURPOSE

The purpose of this study was to comprehensively and quantitatively review eligible published studies to explore the prognostic significance of vascular endothelial growth factor (VEGF) expression in patients with esophageal carcinoma (EC).

METHODS

PubMed and Embase databases were searched until September 11, 2011. A meta-analysis was performed to demonstrate any relationship between VEGF and 5-year overall survival (OS) in EC patients.

RESULTS

The final analysis included 1453 patients from 19 studies. The studies were grouped by patient source, histology, VEGF isoform and cutoff value. The estimated risk of death suggested that VEGF positivity had negative impact on prognosis of patients with EC, esophageal squamous cell carcinoma (ESCC) and Asian patients. The risk ratios (RR) and 95% confidence interval (95% CI) were 1.26 (1.16-1.37) in EC patients, 1.28 (1.16-1.40) in ESCC patients and 1.35 (1.24-1.48) in Asian patients. Furthermore, when the cutoff value was set at 10% in 6 studies, the RR (95% CI) was 1.48 in the VEGF positive group (1.27-1.73). In addition, VEGFC was also correlated with patient poor prognosis with a RR (95% CI) of 1.30 (1.15-1.48). However, EC patients from non-Asian countries and cutoff value at 30% showed no significant correlation with survival. Data were not sufficient to determine the prognostic value of VEGF expression in esophageal adenocarcinoma (EA) patients and VEGFD expression.

CONCLUSIONS

VEGF positivity indicated poor prognosis in patients with EC, ESCC and of Asian origin. Cutoff value at 10% may be a more appropriate standard to define VEGF positivity. VEGFC also correlated with poor prognosis in EC patients.

Lymphangiogenesis and prognostic significance of vascular endothelial growth factor C in gastro-oesophageal junction adenocarcinoma

Vascular endothelial growth factor C (VEGF-C) is a crucial regulator of the development of lymphatic vessels and is involved in the lymph node metastasis of cancer. The levels of VEGF-C expression and lymphatic vessel density (LVD) in 128 gastro-oesophageal junction adenocarcinoma (GEJA) tissues were examined by immunohistochemistry and analysed for their association with clinicopathological features and disease-free survival. We found that 75.0% of tumour samples displayed strong immunoreactivity to VEGF-C. The levels of VEGF-C expression in the tumour tissues were associated with the stages of the clinical tumours and the lymph node metastasis status, but not with the age, gender and the size and type of tumours in the cohort. Similarly, LVD, as evaluated by anti-D2-40 staining, was also associated with the clinical stages of GEJA. The values of LVD were positively correlated with the levels of VEGF-C expression in these samples (r = 0.3760, P = 0.0001). High levels of VEGF-C expression and high values of LVD were associated with shorter periods of disease-free survival (DFS) in patients with GEJA (P < 0.001). In addition, GEJA at N1 and N2 stages, at T4 stage, chemotherapy after surgery, high levels of VEGF-C expression and lower marginal resection were independent factors for the prognosis of DFS in patients with GEJA. Our data indicate that VEGF-C may promote the lymphangiogenesis and lymphatic metastasis of GEJA and that VEGF-C may be a valuable biomarker for the diagnosis of lymphatic metastasis and a prognostic factor of the survival of patients with GEJA.

Localization and signaling patterns of vascular endothelial growth factors and receptors in human periapical lesions

INTRODUCTION

Vascular endothelial growth factors (VEGFs) and their receptors (VEGFRs) are key players in vasculogenesis and are also involved in pathologic conditions with bone destruction. Vasculogenesis is critical for disease progression, and bone resorption is a hallmark of apical periodontitis. However, the localization of VEGFs and VEGFRs and their gene signaling pathways in human apical periodontitis have not been thoroughly investigated. The aim of this study was to localize VEGFs and VEGFRs and analyze their gene expression as well as signaling pathways in human periapical lesions.

METHODS

Tissue was collected after endodontic surgery from patients diagnosed with chronic apical periodontitis. Periodontal ligament samples from extracted healthy wisdom teeth was also collected and used as control tissue. In lesion cryosections, VEGFs/VEGFRs were identified by immunohistochemistry/double immunofluorescence by using specific antibodies. A human VEGF signaling polymerase chain reaction array system was used for gene expression analysis comparing lesions with periodontal ligament samples.

RESULTS

The histologic evaluation revealed heterogeneous morphology of the periapical lesions with various degrees of inflammatory infiltrates. In the lesions, all investigated factors and receptors were identified in blood vessels and various immune cells. No lymphatic vessels were detected. Gene expression analysis revealed up-regulation of VEGF-A and VEGFR-3, although not significant. Phosphatidylinositol-3-kinases, protein kinase C, mitogen-activated protein kinases, and phospholipases, all known to be involved in VEGF-mediated angiogenic activity, were significantly up-regulated.

CONCLUSIONS

The cellular and vascular expressions of VEGFs and VEGFRs in chronic apical periodontitis, along with significant alterations of genes mediating VEGF-induced angiogenic responses, suggest ongoing vascular remodeling in established chronic periapical lesions.

[Diagnostic value of enhanced computed tomography plus vascular endothelial growth factor C expression in hilar and mediastinal lymph node metastasis of non-small cell lung cancer]

OBJECTIVE

To explore the diagnostic value of preoperative enhanced computed tomography (CT) plus vascular endothelial growth factor C (VEGF-C) expression in hilar and mediastinal lymph nodes metastasis of non-small cell lung cancer.

METHODS

A total of 87 patients with non-small cell lung cancer (NSCLC) received preoperative chest enhanced CT scans and underwent standard radical operation and systematic lymph node dissection. Pathologic examination was selected as the gold standard to determine lymph node metastasis. The immunohistochemical method was used to detect the expression of VEGF-C. The predicting values of chest enhanced CT, VEGF-C expression and their combination for the diagnosis of hilar and mediastinal lymph nodes metastasis were evaluated through comparing the sensitivity, specificity and accuracy.

RESULTS

The sensitivity of CT scan was 75.0%, specificity 59.6% and accuracy 66.7%. The positive expression rate of VEGF-C was 78.2% (68/87) and strong positive rate 13.8% (12/87). The sensitivity of VEGF-C was 97.5%, specificity 38.3% and accuracy 65.5%. The combination of CT and VEGF-C had a better accuracy (74.7%) and the sensitivity and specificity were 80.0% and 70.2% respectively.

CONCLUSION

Compared with CT scan or VEGF-C expression alone, the combination of CT and VEGF-C improves the specificity and accuracy of diagnosing lymph nodes metastasis in NSCLC. If this combination method is employed before therapy, the accuracy of clinical nodal staging may be enhanced.

Expression of vascular endothelial growth factor C in human pterygium

Vascular endothelial growth factor C (VEGF-C) and its receptor VEGFR-3 mediate lymphangiogenesis. In this study, we analyzed the expression of VEGF-C and VEGFR-3 as well as lymphatic vessels in the pterygium and normal conjunctiva of humans. Fifteen primary nasal pterygia and three normal bulbar conjunctivas, surgically removed, were examined in this study. The lymphatic vessel density (LVD) and blood vessel density were determined by the immunolabeling of D2-40 and CD31, markers for lymphatic and blood vessels, respectively. VEGF-C and VEGFR-3 expression in pterygial and conjunctival tissue proteins was detected by Western blotting and were evaluated using immunohistochemistry. The LVD was significantly higher in the pterygium than normal conjunctiva (p < 0.05). Western blot demonstrated high-level expression of VEGF-C and VEGFR-3 in the pterygium compared with normal conjunctiva. VEGF-C immunoreactivity was detected in the cytoplasm of pterygial and normal conjunctival epithelial cells. The number of VEGF-C-immunopositive cells in pterygial epithelial cells was significantly higher than in normal conjunctival cells (p < 0.05). VEGFR-3 immunoreactivity was localized in the D2-40-positive lymphatic endothelial cells. The present findings suggest the potential role of VEGF-C in the pathogenesis and development of a pterygium through lymphangiogenesis and the VEGF-C/VEGFR-3 pathway as a novel therapeutic target for the human pterygium.

[Clinical study of tissue expression and serum contents of VEGF-C in cervical diseases of Uighur women]

OBJECTIVE

To detect the VEGF-C expression in the serum and tissue of cervical diseases. To explore correlation of tissue and serum expression and the clinical significance of VEGF-C in the cervical intraepithelial neoplasia and cervical squamous-celled carcinoma of Uighur momen in Xinjiang.

METHOD

(1) The VEGF- C expressions in tissue were tested by immunohistochemisty from the 22 chronic cervicitis, 24 CIN,and 43 squamous-celled carcinoma patients, (2) The VEGF-C contents in the serum were tested by enzyme-linked immunosorbent assay (ELISA) from the 15 chronic cervicitis, 23 CIN, and 40 squamous-celled carcinoma patients.

RESULT

(1) The expression of VEGF-C in the tissue of cervicitis, CIN and cervical carcinoma were separately 9.1%, 87.50%, 100%, the differences had significance (P < 0.05). (2) The VEGF-C serum contents were gradually increased from cervicitis to CIN and cervical carcinoma, the differences had significance (P < 0.05). (3) The compartment of results of VEGF-C in serum and tissue showed that, there were correlation between to of them, the more tissue expressions, the more serum expressions will be (r = 0.27, F = 5.327, P < 0.05).

CONCLUSION

VEGF-C has played an facilitation rule in the transition process of CIN to cervical squamous cell carcinoma of the Uygure women in Xinjiang, there are correlation of VEGF-C expression between tissue and serum.

Correlated expression of Fas, NF-kappaB, and VEGF-C in infiltrating ductal carcinoma of the breast

OBJECTIVE

To investigate the expressions of Fas, NF-kappaB, and vascular endothelial growth factor-C (VEGF-C) in infiltrating ductal carcinoma of the breast and provide scientific basis for early diagnosis and prognosis of breast cancer.

MATERIALS AND METHODS

The immunohistochemical technique (SP method) was used to detect expression of Fas, NF-kappaB, and VEGF-C in 137 cases of breast-infiltrating ductal carcinoma, 17 cases of intraductal carcinoma of the breast, and 20 cases of normal breast tissues, and analyze its relationship with clinicopathologic factors of breast cancer and patients' survival rate, as well as the correlation among their expression, clinicopathologic factors, and survival rate.

RESULTS

Fas expression was less commonly detected in infiltrating ductal carcinoma than in intraductal carcinoma and normal tissue. In contrast, both NF-kappaB and VEGF-C were more commonly detected in infiltrating ductal carcinoma than in intraductal carcinoma and normal tissue. Fas expression was correlated with tumor size, histological grade, and clinicopathological stage; NF-kappaB expression was correlated with tumor size, histological grade, lymph node metastasis; VEGF-C expression was correlated with lymph node metastasis and clinical and pathological stages of breast cancer (p < or = 0.05). Spearman rank correlation analysis revealed a negative correlation between Fas expression and both NF-kappaB and VEGF-C expression in infiltrating breast cancer (p < 0.05) Additionally, Kaplan-Meier survival analysis demonstrated that five-year survival was higher for patients with Fas-positive samples but lower for those with VEGF-C-positive samples.

CONCLUSIONS

The present results demonstrate that Fas and NF-B play a role in the initiation and development of breast cancer, while VEGF-C appears to promote lymph node metastasis. Thus, these proteins may serve as useful diagnostic and prognostic markers of invasive breast cancer.

Vascular endothelial growth factor-C and its receptor type-3 expressed in acute lymphocytic leukemia cases with t(1;19)

The vascular endothelial growth factor (VEGF)-C system was analyzed in two cases of acute lymphocytic leukemia (ALL) with TCF3/PBX1 fusion to determine whether the VEGF-C system influences the growth of these ALL blasts. Bone marrow non-adherent mononuclear cells were prepared from the patients, and expressions of VEGFs and VEGF receptors (VEGFRs) were analyzed based on RNA and protein levels. Cell proliferation was also assayed with or without neutralizing antibodies to VEGFs. The patients' leukemic blasts expressed a significant amount of VEGF-C and VEGFR type-3. When anti-VEGF-C antibody was added to the blast cell cultures, cell proliferation was suppressed. These observations indicate that, in our ALL cases with TCF3/PBX1 fusion, VEGF-C autocrine stimulation plays an important role in the proliferation of ALL.

Expression of IGF-1R, VEGF-C and D2-40 and their correlation with lymph node metastasis in endometrial adenocarcinoma

Insulin-like growth factor-1 receptor (IGF-1R) regulates carcinogenesis and tumor development and is expressed in normal endometrium. Vascular endothelial growth factor C (VEGF-C) promotes lymph node metastasis. We investigated IGF-1R, VEGF-C and D2-40 in endometrial adenocarcinoma and the association between IGF-1R and lymphatic metastasis, using an immunohistochemical S-P method with 40 cases of endometrial adenocarcinoma and 14 of normal endometrium. IGF-1R expression differed significantly between normal endometrium and adenocarcinoma; it was associated with histological grade but not surgical stage. IGF-1R overexpression was associated with metastasis, but expression was not. VEGF-C expression was greater in normal endometrium than in adenocarcinoma and was associated with metastasis but not with surgical stage or histological grade. IGF-IR and VEGF-C expression were correlated in endometrial adenocarcinoma, and lymphatic vessel density was closely related to both. Abnormal IGF-IR and VEGF-C expression may be important in lymph node metastasis of endometrial adenocarcinoma and might be used to evaluate the prognosis.

Clinical significance of vascular endothelial growth factors C and D and chemokine receptor CCR7 in gastric cancer

BACKGROUND/AIM

This study was designed to investigate the clinical significance of lymphangiogenic vascular endothelial growth factors C and D, and chemokine receptor CCR7 in the lymphatic spread of gastric cancer.

PATIENTS AND METHODS

The expressions of VEGF-C and -D, and CCR7 were examined in 82 gastric tumors showing a discrepancy between the degree of lymphatic invasion (Ly) and the status of lymph node metastasis (N) (Ly+N-: 72, and Ly-N+: 10 patients).

RESULTS

High expression of VEGF-C and -D, and CCR7 was present in 88%, 63% and 67% of cases, respectively. The VEGF-C expression was significantly higher in Ly+N- than Ly-N+ (p<0.05), but VEGF-D and CCR7 were not. CCR7 expression was a prognostic factor in the Ly+N- subgroup (p<0.05), but VEGF-C and -D were not.

CONCLUSION

VEGF-C and -D and CCR7 may play critical roles in lymphatic invasion in primary tumors. CCR7 expression should provide prognostic information in node-negative gastric cancer patients showing lymphatic invasion.

Low molecular weight heparin suppresses lymphatic endothelial cell proliferation induced by vascular endothelial growth factor C in vitro

BACKGROUND

Pancreatic cancer is one of the most aggressive human malignancies. Lymphangiogenesis plays an important role in lymph node metastasis of many solid tumors. It is well known that low molecular weight heparins (LMWHs) can inhibit cell growth, cell invasion and angiogenesis, which are key processes in tumor progression.

METHODS

We measured the expression of vascular endothelial growth factor C (VEGF-C) in pancreatic cancer cells (PANC-1) using reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting. We used an in vitro assay to evaluate the anti-lymphangiogenic effect of an LMWH, Fragmin, on human lymphatic endothelial cell (HLEC) proliferation.

RESULTS

Fragmin at a low concentration can effectively inhibits HLEC proliferation induced by VEGF-C. VEGF-C secreted by PANC-1 cells stimulated HLEC proliferation. Low concentration LMWH suppressed HLEC proliferation induced by VEGF-C but did not affect proliferation or VEGF-C expression of PANC-1 cells, whereas high concentrations of LMWH inhibited PANC-1 cell proliferation.

CONCLUSIONS

These results suggest that VEGF-C released by cancer cells plays an important role in promoting HLEC proliferation. The LMWH Fragmin has anti-lymphangiogenic effects and may inhibit lymphatic metastasis in pancreatic cancer.

Lymphangiogenesis in gastric carcinoma correlates with prognosis

Lymphatic metastasis is an important way that gastric carcinomas can spread. However, little is known about the mechanisms of lymphangiogenesis and its clinical significance in gastric carcinomas. In the present study, lymphatic vessel density (LVD), VEGF-C expression, and proliferative activity of lymphatic endothelium were determined in human gastric carcinomas and xenografts of gastric cancer cells in nude mice. The development of lymphangiogenesis and its correlation with patient prognosis were investigated. The results showed that lymphatic vessels were observed mainly in peripheral tumour tissue with significantly (p < 0.05) higher P-LVD (peri-tumoural-LVD) than I-LVD (intra-tumoural-LVD). The expression of VEGF-C was heterogeneous within tumours, with a significantly higher expression (immunostaining score) at the margin than at the tumour centre (p < 0.05). A significant correlation was found between VEGF-C expression at the margin (but not at the centre) and P-LVD (r = 0.72, p < 0.01). High proliferative activity of lymphatic endothelium was also observed in the peripheral tissues, with a significant correlation between proliferative activity of lymphatic endothelium and VEGF-C expression (p < 0.05). These data imply that the increased lymphatics may have been newly formed following stimulation by VEGF-C. High VEGF-C expression at the margin of gastric carcinomas could induce lymphangiogenesis in the peri-tumoural stroma and contribute to the increased P-LVD. The data from mice tumour xenografts also suggested that VEGF-C produced from the transplanted gastric carcinoma cells could induce lymphangiogenesis around them. In patients, VEGF-C expression at tumour margins was associated with nodal metastasis, lymphatic vessel invasion, poor recurrence-free survival, and poor overall survival, and could serve as an independent predictor for patients with gastric carcinoma.

Effects of angiotensin-converting enzyme inhibitors and angiotensin II type 1 receptor blockers on lymphangiogenesis of gastric cancer in a nude mouse model

BACKGROUND

Angiotensin-converting enzyme inhibitors (ACEI) and angiotensin II type 1 receptor blockers (ARB) can inhibit tumor growth by inhibition of angiogenesis. This study was designed to study the anticancer effects of ACEI and ARB on tumor growth and lymphangiogenesis in an implanted gastric cancer mouse model.

METHODS

A model of gastric cancer was established by subcutaneously inoculating human gastric cancer cell line SGC-7901 into 60 nude mice. One week later, all mice were randomly divided into 5 groups. A control group received physiologic saline once daily for 21 days. Mice in the 4 treatment groups received one of the following agents by gavage once daily for 21 days: perindopril, 2 mg/kg; captopril, 5 mg/kg; losartan, 50 mg/kg; or valsartan, 40 mg/kg. Twenty-one days after treatment, all the mice were sacrificed and the tumors were removed. Tumor sections were processed, and immunohistochemical methods were used to observe the expressions of vascular endothelial growth factor C (VEGF-C), matrix metalloproteinase 7 (MMP-7), and lymphatic microvessel density (LMVD).

RESULTS

Tumor volume was significantly inhibited in all ACEI and ARB groups, compared with the control group (all P < 0.01). LMVD in the ACEI and ARB groups was also significantly lower than that of the control group (all P < 0.01). In the ACEI groups, the expressions of VEGF-C and MMP-7 were both significantly decreased, compared with the control group (all P < 0.05). In the ARB groups, expression of VEGF-C was significantly decreased compared with the control group (all P < 0.05). However, no significant difference was found in the expression of MMP-7 between ARB groups and the control group.

CONCLUSION

In a mouse model, ACEI and ARB might inhibit gastric cancer tumor growth by suppressing lymphangiogenesis.

Lymphangiogenesis in kidney cancer: expression of VEGF-C, VEGF-D and VEGFR-3 in clear cell and papillary renal cell carcinoma

The vascular endothelial growth factors VEGF-C, VEGF-D and its receptor, VEGFR-3, are overexpressed in different malignancies and associated with lymph node metastasis and poor prognosis. We analysed these factors in clear cell (ccRCC) and papillary (pRCC) renal cell carcinoma (RCC). The results were correlated with various clinicopathological parameters (CPP). We constructed a tissue microarray with tumor samples of 135 (81%) ccRCC and 31 (19%) pRCC. After immunohistochemical staining using polyclonal antibodies for VEGF-C, VEGF-D and VEGFR-3, a semiquantitative analysis was performed to determine the levels of expression. The results were compared between the two subgroups and were correlated with CPP. In the two subgroups the expression of VEGF-C was significantly correlated with that of VEGF-D (p<0.001). There was an increased expression of VEGF-C in 11% of ccRCC and 36% of pRCC (p=0.002). VEGF-D expression was positive by means of analysis in 22% of ccRCC and 42% of pRCC (p=0.039). There was no significant difference regarding the expression of VEGFR-3 between the subgroups (44% ccRCC and 61% pRCC, p=0.11). No correlation was found between the expression of the analysed parameters and CPP (TNM, grading, progression-free survival and overall survival) in either the entire group or in the two subgroups. In summary, ccRCC and pRCC show a different expression pattern of the analysed lymphangiogenic factors. Further studies are necessary to confirm these results and to determine whether the VEGF-C/VEGF-D/VEGFR-3-axis can play a role as a prognostic tool or a target for therapeutic intervention in renal cell carcinoma.

Expression of vascular endothelial growth factor C is a prognostic indicator in esophageal cancer

BACKGROUND/AIMS

Vascular endothelial growth factor plays an important role in angiogenesis and vascular endothelial growth factor-C is concerned with lymphangiogenesis.

METHODOLOGY

The present study employed immunostaining to investigate the relationship between expression of these factors and clinicopathologic findings in 100 patients with esophageal cancer.

RESULTS

Fifty-six of the 100 tumors (56%) showed expressed vascular endothelial growth factor and 43 tumors (43%) expressed of vascular endothelial growth factor-C. Expression of the latter was correlated with the depth of tumor invasion (p=0.0095), lymphatic invasion (p=0.0065), lymph node metastasis (p=0.0l34). The prognosis was significantly worse for patients with tumors positive for vascular endothelial growth factor-C than for those with negative tumors (p=0.036). In contrast, expression of vascular endothelial growth factor was not correlated with the prognosis. Microvessel density was significantly higher in tumors expressing vascular endothelial growth factor-C compared with negative tumors (p=0.0014). Stepwise multivariate analysis with Cox's proportional hazards model identified gender (p=0.0420), age (p=0.0192), vascular endothelial growth factor-C expression (p=0.0286), and lymphatic invasion (p=0.0030) as prognostic determinants.

CONCLUSIONS

Expression of vascular endothelial growth factor-C is related to lymphatic invasion and is a prognostic indicator for esophageal cancer.

Clinical significance of intra-tumoral sinusoidal structures showing lympho-endothelial immunoreactivity in breast cancer

The lymphatic system is known as one of the most important pathways in the disease progression of breast cancer. In this study, we investigated lymphatic systems intra-tumorally, and found a unique structure displaying lymphoendothelial immunoreactivity. These incomplete vessel-like structures that formed sinusoids and specifically reacted with the D2-40 antibody, were found in the tumor stroma and were often infiltrated by cancer cells. To show the clinical significance of these intra-tumoral sinusoidal structures (ISS), we examined 113 specimens of surgically resected breast cancer. In multivariate logistic regression analysis, lymph node status (p=0.024) and disease recurrence (p=0.008) were the independent factors that correlated with the existence of ISS. Positive ISS detection in the tumor correlated more strongly with lymph node metastases than positive lymphovascular invasion by cancer cells. Furthermore, a significant correlation with frequent recurrence and poorer survival were recognized in patients with ISS (p<0.001, log-rank test). The evaluation of ISS by needle-biopsied specimens was as accurate as that with surgical specimens, and a significant correlation between the positive ISS evaluated by biopsy and positive lymph node status (p=0.020) was found. In conclusion, ISS are unique structures which play a crucial role in disease progression through lymphatic systems in breast cancer. In a clinical setting, the detection of ISS by biopsy specimen should be considered as a method for determining prognosis instead of a whole tumor examination.

VEGF-C expression in squamous cell carcinoma and adenocarcinoma of the esophagus

BACKGROUND

Vascular endothelial growth factor C (VEGF-C) is the only factor known to cause lymphangiogenesis. In esophageal cancer the histologic tumor type and lymph node metastasis are independent predictors of recurrence and poor outcome. To evaluate the rule of VEGF-C expression in esophageal cancer, we investigated 113 specimens, 59 squamous cell and 54 adenocarcinomas of the esophagus.

METHODS

The expression of VEGF-C was evaluated using immunohistochemistry (IHC) on 59 paraffin-embedded archival specimens from patients with squamous cell esophageal carcinomas and 54 paraffin-embedded archival specimens of patients with esophageal adenocarcinomas arising in Barrett's mucosa. All patients had a complete tumor resection. A complete and updated follow-up was available for all patients.

RESULTS

The expression of VEGF-C was significantly different between the two histological types of esophageal tumors. Patients with squamous cell carcinoma and lymph node metastases had a significantly higher VEGF-C expression (P < 0.01). In patients with adenocarcinoma of the esophagus there was no correlation between VEGF-C expression and clinicopathological parameters. High VEGF-C expression tended to be correlated with poor survival in squamous cell cancer but not in adenocarcinoma of the esophagus.

CONCLUSIONS

The present study indicates that VEGF-C may play a role in tumor progression via lymphangiogenesis in squamous cell carcinoma of the esophagus. This seems not to be true for the adenocarcinoma of the esophagus. These data could help with the understanding of the different onset and characteristics of lymph node metastasis in squamous cell carcinoma and adenocarcinoma of the esophagus.

Lymphangiogenesis in myocardial remodelling after infarction

Ishikawa Y, Akishima-Fukasawa Y, Ito K, Akasaka Y, Tanaka M, Shimokawa R, Kimura-Matsumoto M, Morita H, Sato S, Kamata I & Ishii T (2007) Histopathology51, 345–353

Lymphangiogenesis in myocardial remodelling after infarction

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

BACKGROUND

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.

METHODS

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.

RESULTS

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).

CONCLUSIONS

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.

Correlations between cyclooxygenase-2 expression and angiogenic factors in primary tumors and liver metastases in colorectal cancer

BACKGROUND

Angiogenesis is required for growth and metastasis of colorectal cancer (CRC), and several positive regulators of tumor angiogenesis have been identified. Cyclooxygenase-2 (COX-2), known to be elevated in several human cancers, regulates angiogenesis by inducing angiogenic factors. The aim of this study was to clarify the levels and evaluate the relationships of COX-2, vascular endothelial growth factor A and C, thymidine phosphorylase (TP) and microvascular density (MVD) in paired tissue specimens between primary CRC and corresponding metastatic liver cancer.

METHODS

Tissue samples from pairs of primary tumors and corresponding metastatic liver tumors from 44 patients with CRC were immunohistochemically evaluated for COX-2, VEGF-A, VEGF-C, TP and MVD.

RESULTS

The primary and corresponding metastatic liver tumors tended to show concordant immunoreactivity for COX-2 (P = 0.005, rs = 0.428), VEGF-A (P = 0.039, rs = 0.314), TP (P = 0.005, rs = 0.422) and MVD (P = 0.046, rs = 0.304) by Spearman rank test. The rate of COX-2 immunoreactivity was higher in liver metastases than in primary tumors (P = 0.002), while the rate of VEGF-A was higher in primary tumors than in liver metastases (P = 0.0004). The incidence of TP immunoreactivity and the level of MVD did not differ between primary and metastatic liver tumors (P = 0.247; P = 0.229). Significant correlations were found between COX-2 immunoreactivity and VEGF-A immunoreactivity in metastatic liver tumors (P = 0.033) as well as in primary tumors (P = 0.008).

CONCLUSION

The positive correlations between COX-2, VEGF-A, TP and MVD in primary CRC and liver metastasis as demonstrated here will help to predict the angiogenic activity of liver metastasis by analyzing primary tumors, allowing for individualized cancer treatment options.

The importance of angiogenesis markers in the outcome of patients with diffuse large B cell lymphoma: a retrospective study of 97 patients

PURPOSE

The role of angiogenesis has been extensively evaluated in solid tumors and more recently in hematologic malignancies. Several surrogate markers of angiogenesis including tumor VEGF, VEGF receptors, and microvessel density have correlated with outcome in some lymphoma studies. This is a single institution retrospective study evaluating the role of angiogenesis markers in the clinical outcome of patients with diffuse large B cell lymphoma (DLBCL).

PATIENTS AND METHODS

A total of 97 patients with DLBCL diagnosed and managed at Indiana University between 1993 and 2001 were included. Archived tumor samples were stained for VEGF-A, VEGF-C, VEGF-R1, and CD31 and graded as negative or positive (1+, 2+, 3+). The relationship between the expression of these markers and the international prognostic variables as well as the progression free survival (PFS) and the overall survival (OS) was evaluated.

RESULTS

VEGF-A, VEGF-C, VEGF-R1 were expressed in 77, 98, and 18% of tumors, respectively. VEGF-A negative patients had an improved OS compared to VEGF-A (1+) (P = 0.0502). VEGF-C correlated with both LDH (r = 0.28, P = 0.0502) and IPI score (r = 0.25, P = 0.013). VEGF-R1 negative patients had a superior survival compared to those with VEGF-R1 (2+) (P = 0.0154).

CONCLUSIONS

The presence of tumor associated angiogenesis may alter the outcome of patients with DLBCL and could be a prognostic factor. Further clinical studies are needed to correlate the degree of angiogenesis with response to anti-angiogenesis agents.

Significance of lymphatic invasion and proliferation on regional lymph node metastasis in renal cell carcinoma

We studied the associations of lymphatic invasion and lymphatic vessel density around tumors with lymph node (LN) status in renal cell carcinoma (RCC) by immunohistochemical analysis using D2-40 antibody as a lymphatic marker. Surgically removed specimens from 76 cases with RCC, including 16 cases with LN metastasis, were used. Lymphatic vessel density around the tumor increased compared with normal kidneys but was not significant by LN status. Tumor size, tumor cell types, patterns of tumor growth, nuclear grade of tumor cells, venous invasion, lymphatic invasion, and primary tumor stage were predictive factors for LN metastasis. Based on multivariate regression analysis, only lymphatic invasion was an independent risk factor for LN metastasis. The immunohistochemical detection of lymphatics was useful for identifying the lymphatic invasion of RCC, and the presence of lymphatic invasion around RCC was an independent predictive factor for LN metastasis.

[Angiogenic factors and their relation to stage, lymph-node micrometastases and prognosis in patients operated on for gastric cancer]

The aim of the present study was to investigate the expression of a number of angiogenic factors such as VEGF, VEGF-C, TGF-alpha and apoptosis in an attempt to relate these biological markers to TNM staging, lymph-node status and prognosis. Angiogenic factors and apoptosis were studied immunohistochemically in 72 gastric cancer cases. The search for micrometastases was performed with an immunohistochemical technique in 20 NO cases. Apoptosis determination was assessed with the TUNEL assay. The chi2 test according to Pearson was used for statistical analysis. The apoptotic index was related to both stage and prognosis: high expression cases showed an earlier stage (p < 0.02) and a better prognosis (p < 0.05). The determination of high neovessel density was related to poorer 5-year survival (p < 0.05). Only the expression of VEGF-C correlated inversely with prognosis (p < 0.05). The presence of micrometastases was unrelated to any of the biological markers studied. Our results partly confirm those reported in the literature. The present study revealed a number of biological markers that may be helpful for identifying particular subgroups of patients. More investigation with similar techniques in large prospective series is needed as a support to clinical practice.

Regional difference in intratumoral lymphangiogenesis of oral squamous cell carcinomas evaluated by immunohistochemistry using D2-40 and podoplanin antibody: an analysis in comparison with angiogenesis

BACKGROUND

Whether tumor cells induce lymphangiogenesis intratumorally or permeate pre-existing lymphatic vessels in the peritumoral area still remains unclear. In this study, we investigated in detail the intratumoral lymphangiogenesis of oral squamous cell carcinomas (SCC) in comparison with tumor angiogenesis.

METHODS

Immunohistochemistry with D2-40, podoplanin antibody, and CD34 antibody were used to evaluate the lymphatic vessel density (LVD) and blood microvessel density (MVD). Vascular endothelial growth factor (VEGF) and VEGF-C expressions of oral SCC were also assessed by immunohistochemistry.

RESULTS

LVD significantly increased in the superficial area of tumor tissue compared with normal mucosa, whereas it decreased in the deep area of intratumoral tissue near the invasion front, in sharp contrast to MVD, which significantly increased throughout tumor tissue. Consistent with the decreased intratumoral LVD and increased intratumoral MVD, VEGF-C expression of tumor cells was down-regulated in the deep area of tumor tissue, while VEGF expression of tumor cells was up-regulated throughout the tumor tissue.

CONCLUSIONS

Lymphangiogenesis in oral SCC varies depending on the region within the tumor tissue. It is not induced in the genuine tumor stroma near the invasion front, probably due to the down-regulation of VEGF-C expression of tumor cells, which is different from VEGF-mediated induction of intratumoral angiogenesis.

Predictive value of vascular endothelial growth factor-C expression for local recurrence of rectal carcinoma

Vascular endothelial growth factor-C (VEGF-C) is considered to be a specific factor promoting lymphangiogenesis. There have been reports of a positive correlation between local recurrence of rectal carcinoma and lymphatic invasion by the tumor. The aim of this study was to determine the clinical significance of VEGF-C expression for identifying lymphangiogenesis as a predictor of the local recurrence of rectal carcinoma. One hundred surgical specimens of rectal carcinoma from patients with (n=26) or without (n=74) local recurrence were studied. VEGF-C protein expression was assessed immunohistochemically. The correlations between VEGF-C expression, various clinicopathologic factors, the microscopic lymphatic vessel density (MLVD), and lymphatic invasion were studied. The MLVD (determined by immunohistostaining for D2-40) was significantly higher in VEGF-C positive tumors than VEGF-C negative tumors. VEGF-C positivity was only correlated with lymphatic involvement. Moreover, multivariate analysis showed that VEGF-C protein expression was an independent risk factor for the local recurrence of rectal carcinoma, and patients with VEGF-C positive tumors had a significantly worse prognosis than those with VEGF-C negative tumors. Expression of VEGF-C may be a good predictor of the local recurrence of rectal carcinoma and may also be a useful prognostic indicator.

Lymphatic and blood vessel morphometry in invasive breast carcinomas: relation with proliferation and VEGF-C and -D proteins expression

INTRODUCTION

The aim of the present study was to investigate the distribution of both lymphatics and blood microvessels in invasive breast carcinomas and the clinicopathological and prognostic significance of their density and size related parameters as well as their correlation with the proliferative potential of the tumor and VEGF-C and -D expression.

METHODS

Both single and double immunohistochemistry were applied on a series of 146 paraffin-embedded breast tissue specimens to detect VEGF-C and -D as well as lymphatics and blood microvessels, respectively. Computer-assisted morphometry was performed to evaluate the blood and lymphatic vessel density (BVD and LVD respectively) as well as various vascular size related parameters.

RESULTS

Lymphatics were detected within the stroma at the tumor border, while blood vessels were located in both the interior of the tumor mass and peritumor stroma. BV major axis, minor axis and perimeter inversely correlated with ER (p=0.011, p=0.023 and p=0.008 respectively), while LV major axis, minor axis and the perimeter inversely correlated with tumor nuclear grade (p=0.045, p=0.037 and p=0.032 respectively) and topoisomerase IIalpha (p=0.015, p=0.024 and p=0.045 respectively). The same LV parameters were found to positively correlate with cancerous VEGF-C (p<0.0001, p=0.092 and p=0.012 respectively) and VEGF-D in the stromal fibroblasts surrounding neoplastic cells (p=0.011, p=0.041 and p=0.026 respectively). High BVD exerted an unfavorable impact on both disease-free (p=0.021) and overall survival (p=0.031) of the patients. High LVD correlated with poor disease-free and overall survival only in the subgroup of patients with ER-negative tumors (p=0.056 and p=0.0312 respectively).

CONCLUSION

These findings, for the first time, correlate lymphatic size with tumors of limited proliferative potential and higher nuclear differentiation. Moreover, they suggest that VEGF-C and -D expression influence lymphatic size rather than being involved in the increase of lymphatic vessel number.

Increased apoptosis and angiogenesis in gastric low-grade mucosa-associated lymphoid tissue-type lymphoma by Helicobacter heilmannii infection in C57/BL6 mice

Helicobacter heilmannii has been reported to cause gastric low-grade mucosa-associated lymphoid tissue-type (MALT) lymphoma, but its precise pathophysiological mechanism remains to be clarified. We recently established a model of gastric B-cell MALT lymphoma in C57BL/6 mice by means of peroral infection of H. heilmannii primarily obtained from cynomolgus monkeys. Using this model, macroscopic, immunohistochemical, and electron microscopic observations of MALT lymphomas were carried out in order to examine the development of apoptosis and angiogenesis. Enhancement of the microvascular network and an increase in vascular endothelial growth factor-A were detected in the central region of the MALT lymphoma tissue in the infected mouse stomach, while vascular endothelial growth factor-C was detected at the margins of the MALT lymphomas. In addition, many H. heilmannii-invaded parietal cells showed caspase-3 immunoreactivity in the fundic mucosal tissue surrounding the MALT lymphoma. In conclusion, in H. heilmannii-induced MALT lymphoma, enhanced immunoreactivity of vascular endothelial growth factor-A and factor-C was observed in areas encircled by increased parietal cell apoptosis, which indicates the pathophysiological relevance of both angiogenesis and apoptosis in MALT lymphoma formation.

Absence of lymphangiogenesis in ductal breast cancer at the primary tumor site

Solid evidence for a relationship between lymphangiogenesis and prognosis in human breast cancer is still lacking. Evidence for ongoing lymphangiogenesis in breast cancer is only provided by animal studies. In the present study we investigated lymphatic vessel density as well as the expression level of the lymphangiogenic factors VEGF-C and -D in a series of 121 ductal breast cancer tissues using immunohistochemical stainings. We found that in the primary tumors the lymphatic vessel density, as well as the expression of both VEGF-C and -D, did not relate to grade, tumor stage, progression or patient survival. Furthermore, in tumors in which lymphatic vessels were present, a Ki-67/podoplanin double staining indicated the absence of proliferating lymphatic endothelial cells. In contrast, we did find a correlation between intratumoral lymphatic vessel density inside the lymph node metastases and patient survival. Another parameter that revealed prognostic value was the presence of tumor cells within the lymphatic vessels. This parameter did predict survival in patients with an age below 63 only. Interestingly, expression of VEGF-D was found to be related to the presence of intralymphatic tumor cells.

Histopathological and lymphangiogenic parameters in relation to lymph node metastasis in early stage oral squamous cell carcinoma

PURPOSE

Lymph node metastasis from oral squamous cell carcinoma (SCC) correlates with a poor prognosis. Therefore, accurate assessment of lymph node status is crucial in treatment planning. Furthermore, prediction of delayed neck metastasis (DNM), especially in early stage tumors with a clinically negative (N0) neck, will determine the need for neck dissection or irradiation. In this study, we assess various clinical, histopathological and lymphangiogenic parameters in early stage oral SCC and their association with DNM.

MATERIALS AND METHODS

Clinical, histological, and immunohistochemical analyses were undertaken for 29 patients with T1N0M0 or T2N0M0 oral SCC affecting the tongue or floor of mouth and correlated with the development of DNM.

RESULTS

Tumor thickness, nuclear pleomorphism, pattern of invasion, and immunohistochemical expression of the lymphangiogenesis-associated molecules VEGFR-3 and VEGF-C were associated with DNM.

CONCLUSIONS

Analysis of these parameters may help to identify patients who would benefit from a neck dissection or irradiation by predicting the likelihood of lymph node metastasis.

Lymphangiogenesis of normal endometrium and endometrial adenocarcinoma

BACKGROUND

Information about lymphatics and lymphangiogenesis in the human endometrium is limited. We investigated the distribution of endometrial lymphatic vessels during the normal menstrual cycle and in association with endometrial adenocarcinoma and investigated the expression of lymphangiogenic growth factors, vascular endothelial growth factor (VEGF)-C, VEGF-D and VEGF receptor-3 (VEGF-R3).

METHODS AND RESULTS

Full thickness uterine samples (n = 23 proliferative; n = 23 secretory) and endometrial adenocarcinoma samples (n = 7 grade I; n = 10 grade III) were collected for the study and analysed by immunohistochemistry and western blotting. Lymphatic vessels of the functionalis were significantly reduced compared with basalis (P = 0.001) across the menstrual cycle with lymphatics of the basalis sometimes intimately associated with spiral arterioles. Lymphatic vessels of endometrial adenocarcinomas were located intra-tumoural and peri-tumoural with significant increases in the peri-tumoural lymphatic vessels compared with normal basalis (P = 0.02). Interestingly, high-grade adenocarcinoma vessels containing tumour emboli demonstrated a mixed blood/lymphatic endothelial cell phenotype. VEGF-C and VEGF-D were immunolocalized in glandular epithelium and some stromal cells with the staining intensity of this localization increasing in endometrial adenocarcinoma. Protein analysis identified VEGF-C (58, 41, 31 and 21 kD) and VEGF-D (56, 41, 31 and 21 kD) and VEGF-R3 (148 and 65 kD) peptides in normal endometrium, with significant increases in several of these peptides for VEGF-C and VEGF-D and no changes in protein expression for VEGF-R3 in endometrial adenocarcinoma.

CONCLUSION

Endometrial lymphatics are significantly reduced in the functionalis, and increases in endometrial adenocarcinoma peri-tumoural lymphatics are associated with increases in VEGF-C and VEGF-D peptides.

Quantitative analysis of lymphangiogenic markers in human gastroenteric tumor

BACKGROUND

Lymphatic spread of gastroenteric tumor cells to regional lymph nodes is one of the early events in metastatic cancers and is often associated with distant metastatic spread and poor prognosis. Expression levels of newly described lymphatic endothelial markers, LYVE-1, VEGF-C, VEGF-D and the VEGF receptors VEGFR-3 were assessed in our study.

METHODS

Paired (tumor and corresponding normal tissue) samples were obtained. The expression level of each factor was determined using RT-PCR and quantified by using a real-time quantitative PCR (RT-QPCR) technique, with respective cloned cDNA plasmids as internal standards.

RESULTS

The expression of VEGF-C and lymphatic endothelial marker VEGFR-3 was significantly greater in patients with lymph node metastasis than in those without metastasis, but no different expression level of VEGF-D and LYVE-1 was detected in both groups of patients. Lymphatic vessel density (LVD), which was assessed by immunohistochemistry for LYVE-1, was correlated with lymphangiogenesis factors and lymph node metastasis. Expression of VEGF-C and VEGFR-3 was significantly associated with higher peritumoral LVD than normal group, and LVD was found greater in the node-positive group than in the node-negative group.

CONCLUSIONS

These results indicate that quantitative analysis of lymphangiogenic marker VEGF-C and VEGFR-3 in gastroenteric specimens may be useful in predicting metastasis of gastroenteric cancer to regional lymph nodes, but the role of LYVE-1 in predicting metastasis of gastroenteric cancer requires further analysis.

Invasive micropapillary carcinoma of the breast: association of pathologic features with lymph node metastasis

Invasive micropapillary carcinoma (IMPC) of the breast is characterized by a high incidence of axillary lymph node metastasis. To investigate the relationship between pathologic features and lymph node metastasis, 51 cases of breast carcinoma with IMPC components were studied. Immunohistochemical analysis for vascular endothelial growth factor (VEGF)-C and VEGF receptor (VEGFR)-3 was performed, and lymphatic vessel density was measured. The main findings included a significantly increased number of positive lymph nodes and/or an increased rate of lymph node metastasis in IMPC with a higher histologic grade, prominent stromal infiltration of lymphocytes, and higher VEGF-C expression and lymphatic vessel density. The percentage of IMPC component in the tumor was not associated with the incidence of lymph node metastasis. The results suggest that the histologic grade, lymphatic vessel density, and lymphocyte infiltration of IMPC are the key factors that influence lymph node metastasis. Further studies are required to elucidate the mechanisms underlying the lymphotropism of this distinct variant of breast carcinoma.

Mediastinal lymphangiomatosis coexisting with occult thymic carcinoma

Mediastinal lymphangiomatosis in a 70-year-old woman was diagnosed on a medical checkup. The tumor was resistant to sclerotherapy with OK432 or bleomycin. The patient continued on a downhill course and died approximately 3 years after the initial diagnosis. Autopsy revealed a large tumor mass occupying the anterior mediastinum and firmly adhered to the pericardium and the pleura. The tumor consisted of two intermingled lesions: dilated vessels lined with D2-40-positive lymphatic endothelium and CD5-positive atypical cell nests with focal keratinization. The former was diagnosed as lymphangiomatosis and the latter as thymic squamous cell carcinoma. Vascular endothelial growth factor (VEGF)-C, a growth factor for lymphatic endothelial cells, was expressed by the carcinoma, and VEGF-C receptor was expressed by the endothelium of lymphangiomatosis. These findings suggested that VEGF-C derived from the thymic carcinoma induced the lymphangiomatosis lesion in a paracrine manner.

The regulation of vascular endothelial growth factors (VEGF-A, -C, and -D) expression in the retinal pigment epithelium

The vascular endothelial growth factor (VEGF) family plays an essential role in vascular development, angiogenesis and lymphangiogenesis. VEGF-A is a key regulator of endothelial cell functions and VEGF-C and VEGF-D are known to stimulate both angiogenesis and lymphangiogenesis. In a surgically removed subretinal vascular membrane of an age-related macular degeneration (AMD) patient, both VEGF-C and VEGF-D were confirmed, in addition to VEGF-A, to be markedly positive in the retinal pigment epithelium (RPE). There is no lymph vessel in ocular tissue, so it is possible that VEGF-C and VEGF-D expression in the RPE play some role in ocular angiogenesis, as well as VEGF-A. Next, we assessed the transition of VEGF-A, -C, and -D expression on several conditions, in human RPE. Hypoxia proverbially induced VEGF-A mRNA expression, meanwhile VEGF-C and VEGF-D mRNA expression was down-regulated. The Ca(2+) deprivation from culture medium strongly up-regulated VEGF-A and VEGF-D mRNA expression. Culture on plastic flasks precoated with poly-2-hydroxyethyl methacrylate up-regulated VEGF-D expression. Meanwhile, no significant change of VEGF-C mRNA expression was found in the blockade of cell-cell and/or cell-matrix adhesion. These findings suggest the possibility that VEGF-C and VEGF-D expression in RPE modify the ocular angiogenesis as angiogenic stimulators.

Intratumoral Lymphatic Vessels and VEGF-C Expression Are Predictive Factors of Lymph Node Relapse in T1-T4 N0 Laryngopharyngeal Squamous Cell Carcinoma

BACKGROUND

The presence of intratumoral lymphatic vessels (ILVs) and the expression of vascular endothelial growth factor-C (VEGF-C) in tumour cells have been studied as markers of lymphangiogenesis in order to evaluate their role in metastatic dissemination in laryngopharyngeal squamous cell carcinoma.

METHODS

A retrospective study was performed in 76 patients of N0 laryngopharyngeal carcinoma. with variable tumour size (T1-T4), histological grade, and location (supraglottic, glottic and hypopharyngeal). The presence of ILVs, as revealed by the expression of PA2.26 antigen and VEGF-C expression, were determined by immunohistochemistry (IHC). Low-grade and high-grade lymphangiogenesis were defined by qualitative and quantitative criteria.

RESULTS

Multivariate analysis revealed low-grade ILV and VEGF-C expression to be associated respectively with 30.3- and 16.2-fold higher probabilities of cervical lymph node relapse (P = 0.005 and P = 0.032) and with 16.2- and 8.44-fold shorter disease-free survival (P = 0.009 and P = 0.045).

CONCLUSIONS

Low-grade ILV and VEGF-C expression are independent predictive factors of cervical lymph node relapse and shortening of time to relapse in N0 laryngopharyngeal carcinoma.

Localisation of lymphatic vessels and vascular endothelial growth factors-C and -D in human and mouse skeletal muscle with immunohistochemistry

The present study was aimed to localise lymphatic vessels and their growth factors in human and mouse skeletal muscle with immunohistochemistry and specific antibodies (VEGFR-3, LYVE-1, VEGF-C and VEGF-D). The largest lymphatic vessels were found in perimysial connective tissue next to the arteries and veins, as has been shown earlier with electron microscopy. As a new finding, we also found small LYVE-1 positive vessels in the capillary bed between muscle fibres. These vessels were located next to CD31 positive blood capillaries and were of the same size, but fewer in number. In addition, we described the localisation of the two main lymphangiogenic growth factor proteins, vascular endothelial growth factor-C and -D. Both proteins were expressed in skeletal muscle at mRNA and protein levels. VEGF-D was located under the sarcolemma in some of the muscle fibres, in the endothelia of larger blood vessels and in fibroblasts. VEGF-C protein was localised to the nerves and muscle spindles, to fibroblasts and surrounding connective tissue, but was not found in muscle fibres or endothelial cells. Our results are the first to suggest the presence of lymphatic capillaries throughout the skeletal muscle, and to present the localisation of VEGF-C and -D in the muscles.

VEGF-C expressing tumor-associated macrophages in lymph node positive breast cancer: impact on lymphangiogenesis and survival

BACKGROUND

The ability of malignant tumors to metastasize presents a severe challenge in cancer treatment. Lymphatic vessels provide one of the main routes for tumor-metastasis on the way to regional lymph nodes. Increasing evidence suggests that inflammatory cells play an important role in tumor-associated angiogenesis and lymphangiogenesis. Recent data show that a specialized sub fraction of tumor-associated macrophages (TAMs) expressing the lymphoangiogenic growth factors vascular endothelial growth factor-C and -D (VEGF-C/D) at the tumor site, is related to lymphangiogenesis, lymphovascular invasion, and lymph node metastasis. Aim of this study was to clear the role of VEGF-C/D expressing TAMs in invasive breast cancer.

METHODS

One hundred-seven cases of lymph node positive invasive breast cancer were included into the study. Lymphatic microvessel density (LMVD), lymphovascular invasion (LVI), peritumoral inflammatory reaction (PI), and VEGF-C expression in tumors (VEGF-C(T)) and TAMs (VEGF-C(C)) were evaluated by immunohistochemistry and in situ hybridization.

RESULTS

Significant associations were seen between LMVD and LVI, LMVD and VEGF-C(T), and between VEGF-C(T) and VEGF-C(C). Further significant correlations were evaluated between VEGF-C(C)/VEGF-C(T) and PI as well as between PI and LVI. LVI remained an independent prognostic factor for disease-free survival and overall survival.

CONCLUSIONS

Our data provide evidence that the peritumoral inflammatory reaction and VEGF-C expressing TAMs may play an important role in tumor lymphangiogenesis and lymphovascular invasion in invasive breast cancer, implying new potential anti-tumor targets.

VEGF-C and COX-2 expression in papillary thyroid cancer

In papillary thyroid cancer (PTC), age appears to be the most important single prognostic factor. Another characteristic feature is the lack of association between survival and lymph node metastases. Earlier, we found that expression of cyclooxygenase-2 (COX-2) is higher in older PTC patients, in agreement with the finding that older patients have a worse prognosis. Recent findings suggest that COX-2 can up-regulate vascular endothelial growth factor-C (VEGF-C) expression. Here, we investigated whether expression of VEGF-C differs between young and older PTC patients and whether expression of VEGF-C and COX-2 are correlated. Our retrospective study comprised 106 PTC patients selected by age: those under 35 or over 55 at diagnosis. Paraffin-embedded tissue samples were analysed by immunohistochemistry for VEGF-C protein expression. Furthermore, we investigated by quantitative RT-PCR and enzyme immunoassay the relationship between VEGF-C and COX-2 expression in papillary thyroid cancer cells (NPA cells). VEGF-C expression was significantly increased with age. In the tumours from older lymph node-positive (N1) patients, VEGF-C expression was significantly higher than in the tumours from young N1 patients. Moreover, all patients who died of cancer or who developed distant metastases were old, and most tumours from these patients (4 of 5) expressed VEGF-C and had had nodal metastases at the time of primary operation. Immunohistochemically, expression of COX-2 and VEGF-C correlated strongly. In cell culture, this correlation was not so clear, because the COX-2 selective inhibitor, NS-398, did not reduce VEGF-C expression. However, as both COX-2 and VEGF-C were induced by the tumour promoter phorbol 12-myristate 13-acetate (PMA), the same factors may control them both.

Impact of lymph node micrometastasis in hilar bile duct carcinoma patients

AIM: To immunohistochemically examine micrometastasis and VEGF-C expression in hilar bile duct carcinoma (HBDC) and to evaluate the clinical significance of the results.

METHODS: A total of 361 regional lymph nodes from 25 patients with node-negative HBDC were immunostained with an antibody against cytokeratins 8 and 18 (CAM 5.2), and immunohistochemical staining of VEGF-C was performed in 34 primary resected tumors.

RESULTS: Lymph node micrometastasis was detected in 6 (24%) of the 25 patients and 10 (2.8%) of the 361 lymph nodes. Patients with micrometastasis showed significantly poorer survival rates than those without (P = 0.025). VEGF-C expression was positive in 17 (50%) of 34 HBDC, and significantly correlated with lymph node metastasis (P = 0.042) and microscopic venous invasion (P = 0.035).

CONCLUSIONS: It is suggested that immunohistochemically detected lymph node micrometastasis has an impact on the outcome of HBDC. VEGF-C expression is highly correlated with lymph node metastasis in HBDC and might therefore be a useful predictor.

Role of lymphangiogenesis and lymphangiogenic factors during pancreatic cancer progression and lymphatic spread

Treatment options for ductal adenocarcinoma of the pancreas are limited by early lymphatic spread, but the lymphatic vessels in pancreatic carcinoma have not been studied to date. Here, we present a histomorphological analysis of lymphatic vessels in pancreatic cancer resection specimens. Both intratumoral and peritumoral tissue were devoid of active lymphangiogenesis. Intratumoral lymphatics were frequently collapsed and non-functional, whereas peritumoral lymphatic vessels were enlarged, and numerous lymphatic vessels were seen in metastases. In addition, we screened pancreatic cancer tissue and pancreatic carcinoma cell lines for mRNA expression of the lymphangiogenic growth factor, VEGF-C; its receptor, VEGFR-3/flt4; and Prox1, a transcription factor essential for embryonic development of both lymphatic vessels and the pancreatic bud. VEGF-C was abundantly expressed in pancreatic cancer tissue and -cell lines and VEGFR-3/flt4 was expressed in cancer stromal cells. Prox1 was strongly expressed in the normal exocrine pancreas but significantly reduced in pancreatic cancer specimens from patients with short survival rates. Well-differentiated cell lines displayed higher levels of Prox1 mRNA than poorly differentiated ones. These results suggest that active lymphangiogenesis is not required for lymphovascular spread of pancreatic cancer. VEGF-C may promote local tumor growth via paracrine signaling to stromal cells expressing VEGFR-3 and support the entry of cancer cells into peritumoral lymphatics. Furthermore, loss of Prox1 function may be a driving force behind pancreatic carcinoma progression.

Expression level of vascular endothelial growth factor-C and -A in cultured human oral squamous cell carcinoma correlates respectively with lymphatic metastasis and angiogenesis when transplanted into nude mouse oral cavity

Angiogenesis is induced by various angiogenic factors including vascular endothelial growth factors (VEGFs), such as VEGF-A, -B, -C and -D, and is involved in tumor progression and metastasis. In an effort to define the expression pattern of VEGFs in oral squamous cell carcinoma (OSCC) and its correlation with clinicopathological factors, we determined the expression levels of VEGFs in OSCC cell lines (HSC-2, HSC-3, HSC-4 and OSC-19) by quantitative RT-PCR and examined their relationship with regional lymph node (LN) and distant metastasis, intratumoral microvessel density (MVD) in tumor transplanted nude mice. We found that HSC-2 and OSC-19 expressed significantly higher levels of VEGF-A and VEGF-C, and caused frequent regional LN metastasis and higher MVD than did the other cell lines. Since VEGF-C is a lymphangiogenic factor, these results suggest that expression of VEGF-C is a useful predictor for LN metastasis.

Inducible nitric oxide synthase activity correlates with lymphangiogenesis and vascular endothelial growth factor-C expression in head and neck squamous cell carcinoma

Nitric oxide (NO) is a diatomic free radical molecule that has been implicated in tumour angiogenesis and progression of head and neck squamous cell carcinoma (HNSCC). However, the mechanism underlying the effect of NO on tumour spread remains largely unknown. Tumour lymphangiogenesis has recently received considerable attention and there is increasing evidence that it is relevant for metastasis to lymph nodes in HNSCC. Here, we study the correlation between inducible NOS synthase (iNOS) activity and lymphangiogenesis in a series of 60 HNSCCs and the possible involvement of the lymphangiogenic factor vascular endothelial growth factor (VEGF)-C. HNSCC presenting with lymph node metastasis had a significantly higher lymphatic vessel density in both the tumour mass and the peritumour area (p = 0.006 and p = 0.001, respectively). Similarly, tumours with lymph node metastasis showed greater lymphatic vessel area than tumours with no lymph node involvement (p = 0.001 for intratumour lymphatics and p < 0.001 for peritumour lymphatics). iNOS activity measured in specimens from the tumour periphery correlated strongly with both lymphatic vessel density and lymphatic vessel area (p = 0.01, rs = 0.45 and p < 0.001, rs = 0.725, respectively). Conversely, these correlations were not observed in specimens from the tumour core. In addition, VEGF-C mRNA expression was significantly elevated in tumours with high iNOS activity (p = 0.008, rs = 0.563), and VEGF-C expression correlated positively with the presence of lymph node metastases (p = 0.03). In vitro, in the A431 human squamous carcinoma cell line, exogenous and endogenous stimulation of the iNOS pathway led to up-regulation of VEGF-C, which was blocked by the NOS inhibitor L-NNA. Taken together, our results indicate that iNOS activity may promote lymphangiogenesis and spread to lymph nodes in HNSCC, with the possible involvement of VEGF-C.