Correlation of Matrix Metalloproteinases and Tissue Inhibitors of Matrix Metalloproteinase Expression in Ileal Carcinoids, Lymph Nodes and Liver Metastasis with Prognosis and Survival

Purpose: Ileal carcinoids are gut epithelial tumors originating from serotonin-containing enterochromaffin (EC) cells. Therapeutic options for effectively inhibiting the growth and spread of metastatic carcinoids are still limited. We aimed to identify the role of matrix metalloproteinases (MMPs) and their endogenous tissue inhibitors (TIMPs) during tumor development and metastasis. Patients and Methods: Tissue samples were obtained from surgically treated patients. Expression of the EC-cell marker, vesicular monoamine transporter-1 (VMAT-1), was used to verify ileal carcinoids. We investigated the differential expression of MMP-2, 7, 9, 11, and 13 and their endogenous inhibitors (TIMP-1, 2, and 3) by quantitative real-time RT-PCR in 25 primary tumors, their corresponding lymph node metastases and/or liver metastases and matched normal mucosa. Results: Significantly increased expression of VMAT-1, MMP-2, MMP-11, TIMP-1 and TIMP-3 was determined by quantitative RT-PCR in EC-cell carcinoids compared to normal intestinal mucosa (p < 0.05). In contrast, MMP-2 and MMP-9 as well as TIMP-1, TIMP-2, and TIMP-3 expression in primary tumors of patients with liver metastases (M1) was significantly lower than in patients lacking liver metastases (M0). EC-cell tumors were significantly larger in the M1 group of tumors, while VMAT-1 expression was significantly decreased. We found an inverse correlation between tumor size and prognosis. Univariate analysis further revealed that decreased expression of VMAT-1, MMP-2 and TIMP-3 in primary tumors was significantly associated with a reduced survival time of the patients. Conclusion: Our data reveal that MMP-2 and TIMP-3 expression together with VMAT-1 expression are of potential prognostic and clinical value in ileal carcinoids. Copyright (C) 2008 S. Karger AG, Base

EC-cell carcinoids of the ileum: expression of matrix metalloproteinases and angiogen growth factors

Das Karzinoid des terminalen Ileums ist ein seltener, langsam wachsender neuroendokriner Tumor mit Ursprung in enterochromaffinen Zellen. Diese Arbeit beschäftigt sich mit dem möglichen Einfluss ausgewählter Matrixmetalloproteinasen (MMP), deren Inhibitoren (TIMP), vaskulärer endothelialer Wachstumsfaktoren (VEGF) und deren Rezeptoren (VEGFR), sowie der Angiogenese und Lymphangiogenese auf Wachstum, Metastasierung und Überlebenszeit. Dazu wurden die relative Expression dieser Faktoren mittels semiquantitativer real-time RT-PCR, sowie die Lymph- und Blutgefäßdichten bestimmt und mit klinischen und histopathologischen Daten korreliert. Dabei zeigte sich unerwarteter Weise fast durchgängig eine inverse Assoziation der Faktoren mit dem Progress der Karzinoide. Gesteigerte Expressionswerte von MMP-2 bzw. VEGF-B erwiesen sich als prognostisch vorteilhaft, eine erhöhte intratumorale Lymphgefäßdichte war dagegen prognostisch negativ.The carcinoid of the terminal ileum is a rare, slow growing neuroendocrine tumour with origin in enterochromaffin cells. This study deals with a possible influence of selected matrix metalloproteinases (MMP), their inhibitors (TIMP), vascular endothelial growth factors (VEGF) and their receptors (VEGFR), as well as angiogenesis and lymphangiogenesis on growth, metastasis, and survival time. For that purpose the relative expression of the parameters by using semi quantitative real-time RT-PCR as well as the lymphatic and blood vessel densities were determined and with clinicopathological data correlated. Thereby an unexpected, nearly continuous inverse coherence of the parameters with the progression of the carcinoids appeared. Increased expression of MMP-2 and VEGF-B turned out to be prognostically favourable; in contrast increased intratumoural lymphatic vessel density was prognostically negative

Vascular endothelial growth factors, angiogenesis, and survival in human ileal enterochromaffin cell carcinoids

BACKGROUND AND AIMS: Well-differentiated neuro-endocrine ileal carcinoids are composed of serotonin-producing enterochromaffin (EC) cells. Life expectancy is determined by metastatic spread to the liver because medical treatment options are still very limited. Selective inhibition of angiogenesis or lymphangiogenesis might prevent tumour growth and metastatic spread. We examined the role of the vascular endothelial growth factors (VEGFs) A, B, C, D, and their receptors (VEGFRs) 1, 2, 3 in angiogenesis and lymphangiogenesis of ileal EC cell carcinoids with and without liver metastases. METHODS: The expression of various VEGFs and VEGFRs was determined by quantitative real-time RT-PCR in healthy mucosa, primary tumour, lymph node metastases and liver metastases of 25 patients with ileal EC cell carcinoids. Microvessel density (MVD) was determined by CD-31 staining in primary tumours and lymphatic vessel density (LVD) by LYVE-1 staining. VEGF expression levels, MVD, LVD, and patients' survival time were correlated using logistic regression and Kaplan-Meier survival analysis. RESULTS: VEGF-A was highly expressed with no difference between normal mucosa and tumours. VEGF-B and -D as well as VEGFR-1 and -2 expression levels were significantly increased in the tumours when compared to normal mucosa. Patients with liver metastasis, however, had a significantly lower expression of the factors A, B, and C and the receptors 2 and 3. MVD in primary tumours positively correlated with the expression of VEGF ligands and their receptors, except for VEGF-D. LVD did not correlate with any VEGF ligand or receptor. Interestingly, low expression levels of VEGF-B were associated with poor survival. CONCLUSION: Patients with more aggressive metastatic spreading had relatively decreased expression levels of VEGF ligands and receptors. Thus, anti-angiogenic therapy may not be a suitable target in metastatic ileal EC cell carcinoids