F.J.G.M. Kubben

Tissue levels of matrix metalloproteinases MMP-2 and MMP-9 are related to the overall survival of patients with gastric carcinoma

Proteinases are involved in tumour invasion and metastasis. Several matrix metalloproteinases (MMPs) have been shown to be increased in various human carcinomas. We assessed the levels of MMP-2 (gelatinase A) and MMP-9 (gelatinase B) in 50 gastric carcinomas and corresponding mucosa using quantitative gelatin zymography. Both MMP levels were significantly enhanced in gastric carcinomas compared with adjacent mucosal tissue, showed a relatively poor intercorrelation and no relation was found with histopathological carcinoma classifications according to Laurén, WHO and tumour-node-metastasis (TNM). Coxs multivariate proportional hazards analyses revealed that high carcinomatous MMP values are of prognostic significance for a poor overall survival of the patients, independent of the major clinicopathological parameters.

Clinical impact of MMP and TIMP gene polymorphisms in gastric cancer

Gastric cancers express enhanced levels of matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs). Single-nucleotide polymorphisms (SNPs) in MMP and TIMP genes may be associated with disease susceptibility and might also affect their antigen expression. We studied the genotype distribution and allele frequencies of SNPs of MMP-2, -7, -8 and -9 and TIMP-1 and -2 in gastric cancer patients in relation to tumour progression, patient survival and tissue antigen expression. The genotype distribution and allele frequencies were similar in gastric cancer patients and controls, except for MMP-7−181A>G. In addition, the genotype distribution of MMP-7−181A>G was associated with Helicobacter pylori status (χ2 7.8, P=0.005) and tumour-related survival of the patients. Single-nucleotide polymorphism TIMP-2303C>T correlated significantly with the WHO classification (χ2 5.9, P=0.03) and also strongly with tumour-related survival (log rank 11.74, P=0.0006). Single-nucleotide polymorphisms of MMP-2, -8, -9 and TIMP-1 were not associated with tumour-related survival. Only the gene promoter MMP-2−1306C>T polymorphism correlated significantly with the protein level within the tumours. First-order dendrogram cluster analysis combined with Cox analysis identified the MMP-7−181A>G and TIMP-2303C>T polymorphism combination to have a major impact on patients survival outcome. We conclude that MMP-related SNPs, especially MMP-7−181A>G and TIMP-2303C>T, may be helpful in identifying gastric cancer patients with a poor clinical outcome.

Matrix metalloproteinase-2 is a consistent prognostic factor in gastric cancer.

In a pioneer study, we showed 10 years ago that enhanced tissue levels of the matrix metalloproteinases (MMPs) MMP-2 and MMP-9 in gastric cancers, as determined by zymography, were related with worse overall survival of the patients. To corroborate these observations, we now assessed MMP-2 and MMP-9 with new techniques in an expanded group of gastric cancer patients (n=81) and included for comparison MMP-7, MMP-8 and the tissue inhibitors of MMPs, TIMP-1 and -2. All MMPs and TIMP-1 were significantly increased in tumour tissue compared to normal gastric mucosa. Matrix metalloproteinase-7, -8 and -9, and the TIMPs showed some correlations with the clinicopathologic parameters TNM, WHO and Laurén classification, but their levels were not related with survival. Regardless of the determination method used, that is, enzyme-linked immunosorbent assay or bioactivity assay, an enhanced tumour MMP-2 level did not show a significant correlation with any of the clinicopathological parameters, but was confirmed to be an independent prognostic factor in gastric cancer.

Tissue level, activation and cellular localisation of TGF-β1 and association with survival in gastric cancer patients

Transforming growth factor-β1 (TGF-β1), a tumour suppressing as well as tumour-promoting cytokine, is stored as an extracellular matrix-bound latent complex. We examined TGF-β1 activation and localisation of TGF-β1 activity in gastric cancer. Gastric tumours showed increased stromal and epithelial total TGF-β1 staining by immunohistochemistry. Active TGF-β1 was present in malignant epithelial cells, but most strongly in smooth muscle actin expressing fibroblasts. Normal gastric mucosa from the same patient showed some staining for total, and little for active TGF-β1. Active TGF-β1 levels were determined by ELISA on tissue homogenates, confirming a strong increase in active TGF-β1 in tumours compared to corresponding normal mucosa. Moreover, high tumour TGF-β1 activity levels were significantly associated with clinical parameters, including worse survival of the patients. Total and active TGF-β1 levels were not correlated, suggesting a specific activation process. Of the different proteases tested, active TGF-β1 levels were only correlated with urokinase activity levels. The correlation with urokinase activity suggests a role for plasmin in TGF-β1 activation in the tumour microenvironment, resulting in transformation of resident fibroblasts to tumour promoting myofibroblasts. In conclusion we have shown localisation and clinical relevance of TGF-β1 activity levels in gastric cancer.

MMP-2 geno-phenotype is prognostic for colorectal cancer survival, whereas MMP-9 is not

The prognostic significance of single-nucleotide polymorphisms (SNPs) and tumour protein levels of MMP-2 and MMP-9 was evaluated in 215 colorectal cancer patients. Single-nucleotide polymorphism MMP-2−1306T and high MMP-2 levels were significantly associated with worse survival. Extreme tumour MMP-9 levels were associated with poor prognosis but SNP MMP-9−1562C>T was not. Tumour MMP levels were not determined by their SNP genotypes.

MMP-2 and MMP-9 in normal mucosa are independently associated with outcome of colorectal cancer patients.

Background:Upregulation of the matrix metalloproteinases MMP-2 and MMP-9 in various cancers has been associated with worse survival of the patients.Methods:We assessed MMP-2 and MMP-9 levels in normal colorectal mucosa from colorectal cancer patients in relation to the course of the disease.Results:A high protein expression of MMP-2 as well as MMP-9 in normal mucosa was found to be correlated with worse 5-year survival. The combination of both parameters was an even stronger prognostic factor. These protein levels were found not to be related to the corresponding single nucleotide polymorphisms of MMP-2 (−1306C>T) and MMP-9 (−1562C>T). Multivariate analyses indicated that the MMP-2 and MMP-9 levels in normal mucosa are prognostic for survival, independent of TNM classification.Conclusion:MMP-2 and MMP-9 levels in normal mucosa are indicative of the course of disease in colorectal cancer patients.

Clinical Applications of the Urokinase Receptor (uPAR) for Cancer Patients

Since decades the urokinase plasminogen activator (uPA) system has been associated with the invasion of malignant cells. The receptor of urokinase (uPAR) is one of the key players in this proteolytic cascade, because it focuses uPAs proteolytic activity to the cell surface and in addition functions as a signaling receptor. uPAR is highly expressed in virtually all human cancers, suggesting possible clinical applications as diagnostic marker, predictive tool of survival or clinical response, and as a target for therapy and imaging. This review summarizes the possibilities of uPAR in clinical applications for cancer patients.

Eradication of Helicobacter pylori infection favourably affects altered gastric mucosal MMP-9 levels.

Background:  Helicobacter pylori gastritis is recognized as an important pathogenetic factor in peptic ulcer disease and gastric carcinogenesis, and is accompanied by strongly enhanced gastric mucosal matrix metalloproteinase‐9 (MMP‐9) levels.