Lymphangiogenesis in non-Hodgkin's lymphoma and its correlation with cyclooxygenase-2 and vascular endothelial growth factor-C.

We aimed to investigate the correlations between lymphangiogenesis, cyclooxygenase (COX)-2 and vascular endothelial growth factor-C (VEGF-C) in non-Hodgkin's lymphoma (NHL) and their associations with the clinical parameters of patients. A total of 75 patients diagnosed with NHL were enrolled in this study. Of the 75 patients, 14 (18.7%) had low-grade and 61 (81.3%) had aggressive lymphoma. We examined the immunohistochemical expression of COX-2 and VEGF-C and estimated lymphangiogenesis by counting lymphatic vessels expressing lymph vessel endothelial hyaluronan receptor-1 (LYVE-1). Our results showed that lymphatic vessel density (LVD) was positive in 59.0% of the cases with aggressive morphology, while the LVD positive rate of indolent lymphoma was only 28.6% (P=0.039). Both COX-2 and VEGF-C were correlated with lymphangiogenesis (P=0.030 and 0.000, respectively). The expression levels of COX-2 and VEGF-C were significantly correlated (P=0.015). LVD, COX-2 and VEGF-C were not correlated with the gender, age, lactate dehydrogenase (LDH) levels, ß2 microglobulin (ß2M) levels, extranodal involvement, disease stage, B symptoms or international prognostic index of the patients. In conclusion, lymphangiogenesis was correlated with aggressive histology in NHL. COX-2 and VEGF-C are inducers of lymphangiogenesis and their expression levels were correlated in NHL.

Vascular endothelial growth factor-A and -C: expression and correlations with lymphatic metastasis and prognosis in colorectal cancer.

Previous studies obtained contradicting results regarding the correlation between expression of VEGF-A, VEGF-C and colorectal cancer patients' clinicopathological features and prognosis. Moreover, the association between the growth factors' expression and lymphatic vessel invasion (LVI) with intratumoral and peritumoral difference has not been reported. In this study, 81 primary colorectal cancer samples were immunohistochemically stained for VEGF-A, VEGF-C and podoplanin. The expression of VEGF-A and VEGF-C in marginal portion was significantly higher than those in central portion (P = 0.000 for both). The expression of VEGF-A in marginal portion was correlated with lymph node metastasis (P = 0.031). The expression of VEGF-C in marginal portion was correlated with TNM stage (P = 0.045), peritumoral LVI (P = 0.048) and lymph node metastasis (P = 0.019). The group with high VEGF-A expression in marginal portion showed worse survival than the low expression group (P = 0.039). Patients with high expression of VEGF-C in the marginal portion were not significantly different from those with low VEGF-C expression (P = 0.121). Patients with high expression of both VEGF-A and VEGF-C in the marginal portion showed the worst survival (P = 0.015). In conclusion, increased expression of VEGF-A and VEGF-C in marginal portion of colorectal cancer was correlated with lymph node metastasis. VEGF-C facilitates colorectal cancer cells invade into peritumoral lymphatic vessels, and different mechanisms may exist in the invasion of tumor cells into peritumoral and intratumoral lymphatic vessels. Assessment the expression of both VEGF-A and VEGF-C in the marginal portion of tumor may help to identify patients with colorectal cancer with unfavourable overall survival.

Intratumoral as well as peritumoral lymphatic vessel invasion correlates with lymph node metastasis and unfavourable outcome in colorectal cancer.

The aim of this study was to assess the intratumoral and peritumoral distribution of lymphatic vessel density (LVD) and lymphatic vessel invasion (LVI) in colorectal cancer and their relationships with patients' clinicopathological characteristics and survival. Paraffin sections of 81 primary colorectal cancers were examined by immunohistochemical staining using monoclonal antibody D2-40. Peritumoral LVD was significantly higher than intratumoral LVD (P = 0.000). Both intratumoral LVD and peritumoral LVD were correlated with the presence of LVI (P = 0.006 and P = 0.003, respectively). LVI, intratumoral LVI and peritumoral LVI were identified, respectively in 38, 28 and 32% of the samples investigated. Both intratumoral LVI and peritumoral LVI were correlated with lymph node metastasis (P = 0.030 and P = 0.014, respectively). Lymph node metastasis, the presence of intratumoral LVI and peritumoral LVI were adversely associated with the 5-year overall survival in a univariate analysis (P = 0.001, P = 0.011 and P = 0.017, respectively). Multivariate analysis using Cox proportional hazard model showed that neither intratumoral LVI nor peritumoral LVI was an independent prognostic factor of overall survival. The results of this study demonstrated that intratumoral as well as peritumoral LVI was associated with lymph node metastasis and adverse outcome in colorectal cancer.

Expression of NOS and HIF-1alpha in human colorectal carcinoma and implication in tumor angiogenesis.

AIM: To study CD34, CD105, inducible nitric oxide synthase (iNOS), endogenous nitric oxide synthase (eNOS), and hypoxia-inducible factor 1 (HIF-1) alpha expression in human colorectal carcinomas. METHODS: The tissue microarrays (TMAs) were made up of 80 cases of colorectal carcinoma and 80 cases of non-neoplasm colorectal mucosa. The expression of CD34, CD105, NOS and HIF-1alpha was detected by immunohistochemistry (S-P). RESULTS: iNOS and HIF-1alpha expression in colorectal carcinoma was significantly higher than in non-neoplasm colorectal mucosa (c2 = 43.166, P < 0.01; c2 = 10.4278, P < 0.01); eNOS expression in colorectal carcinoma was significantly lower than in non-neoplasm colorectal mucosa (c2 = 11.354, P < 0.01). The expression of iNOS correlated with differentiation (c2 = 18.141, P < 0.01), invasive depth (c2 = 4.748, P < 0.01), and Micro vessel density (MVD) (t = 2.327, P < 0.05). The expression of HIF-1alpha was correlated with infiltrating depth (c2 = 4.397, P < 0.05), Dukeos staging (c2 = 4.255, P < 0.05), and MVD (t = 2.272, P < 0.05). No correlation was found in eNOS expression. CONCLUSION: Over-expression of iNOS and HIF-1alpha in colorectal carcinoma is correlated with the biological character MVD.

Relationship between expression of CD105 and growth factors in malignant tumors of gastrointestinal tract and its significance.

AIM: Angiogenesis is an important step in the growth of solid malignant tumors. A number of angiogenic factors have been found such as transforming growth factor beta1 (TGF-beta1) and vascular endothelial growth factor (VEGF). However, the roles of TGF-beta1 and VEGF in gastrointestinal carcinogenesis are still unclear. This study was to investigate the expressions of TGF-beta1 and VEGF in gastrointestinal tract malignant tumors, as well as their association with microvessel density (MVD). At the same time, we also observed the localization of TGF-beta1 and its receptor CD105 in gastric malignant tumors. METHODS: The expressions of TGF-beta1 and CD105 were detected in 55 fresh specimens of gastric carcinoma and VEGF and CD105 in 44 fresh specimens of colorectal carcinoma by immunohistochemical staining (S-ABC). TGF-beta1 and CD105 in 55 gastric carcinoma tissues on the same slide were detected by using double-stain Immunohistochemistry (DS-ABC). RESULTS: Among the 55 cases of gastric carcinoma tissues, 30 were positive for TGF-beta1 (54.55%). The MVD of TGF-beta1 strong positive group (++ approximately +++ 23.22 +/- 5.8) was significantly higher than that of weak positive group (+17.56 +/- 7.2) and negative group (- 17.46 +/- 3.9) (q=4.5, q=5.3207, respectively, P<0.01). In the areas of high expression of TGF-beta1, MVD and the expression of CD105 were also high. Among the 44 cases of colonic carcinoma tissues, 26 were positive for VEGF (59.1%). The expressions of both VEGF and CD105 (MVD) were related with the depth of invasion (F=5.438, P<0.05; F=4.168, P=0.05), lymph node metastasis (F=10.311, P<0.01; F=20.282, P<0.01) and Dukes stage (F=6.196, P<0.01; F=10.274, P<0.01), but not with histological grade (F=0.487, P>0.05). There was a significant correlation between the expression of VEGF and CD105 (MVD) (r=0.720, P<0.01). CONCLUSION: Over-expression of TGF-beta1 and VEGF acts as stimulating factors of angiogenesis in gastrointestinal tumors. CD105, as a receptor of TGF-beta1, can regulate the biological effect of TGF-beta1 in tumor angiogenesis. MVD marked by CD105 is more suitable for detecting newborn blood vessels.