Significance of collagenase 3 (matrix metalloproteinase 13) in invasive bladder cancer: correlation with pathological parameters

The role of matrix metalloproteinase MMP-9 and TIMP-2 tissue inhibitor of metalloproteinases as serum markers of bladder cancer

INTRODUCTION

The diagnosis and molecular staging of bladder cancer based on the detection of gelatinases mRNA (MMP-2 and MMP-9) in peripheral blood circulating and mononuclear cells have shown promising results. We analyze if the determination of the corresponding protein synthesis products makes it possible to diagnose and characterize patients with bladder cancer.

MATERIAL AND METHOD

Quantification of the serum levels of MMP-2, MMP-9 and TIMP-2 in a series of 42 individuals (31 patients with bladder cancer in different stages and 11 healthy controls) using the ELISA technique was carried out. The determinations were compared between cases and controls (Mann-Whitney U) and between different groups of tumors (Mann-Whitney U or Kruskal-Wallis), according to the clinical-pathological characteristics (age, gender, T category, M category or grade). Diagnostic yield of these markers was evaluated by analysis of the ROC curves.

RESULTS

There is a correlation between the determinations of MMP-2 and TIMP-2 (R=.699; P>.0001) and MMP-9 and TIMP-2 (R=.305; P=.049). Patients with bladder cancer have higher levels of MMP-9 (p<0.0001) and TIMP-2 (P=.047) than the controls. Furthermore, the MMP-9/TIMP-2 ratio is also superior in cancer patients (P<.001). Differences were not detected between cancer and controls regarding age (P=.64) or gender (P=.64). Differences were also not detected regarding MMP-2 (P=.35) or MMP-2/TIMP-2 rate (P=.45). Within the cancer patient population, the MMP-2 and MMP-9 values differ according to T category (P=.022 and P=.038, respectively) and those of the TIMP-2 according to M category (P=.036). ROC curve analysis showed that both MMP-9 and the MMP-9/TIMP-2 ratio discriminate patients with cancer and controls, with equivalent diagnostic accuracy (ABC 0.953) and cut offs of 3.93 ng/mL (S 90%; Sp 81%) and 0.053 ng/mL (S 96%; Sp 84%), respectively.

CONCLUSIONS

The results obtained suggest that both serum MMP-9 and TIMP-2 would have an application in the prediction of the development and progression of bladder cancer, and a potential utility as clinical markers of the disease. Multicenter, prospective studies that confirm their preliminary results are necessary.

Matrix Metalloproteinases and Bladder Cancer: What is New?

Urothelial bladder cancer represents a heterogeneous disease with divergent pathways of tumorigenesis. Tumor invasion and progression are a multifactorial process promoted by microenvironmental changes that include overexpression of matrix metalloproteinases (MMPs). Recent data clearly challenge the classic dogma that MMPs promote metastasis only by modulating the remodeling of extracellular matrix. Indeed, MMPs have also been attributed as an impact on tumor cell behavior in vivo as a consequence of their ability to cleave growth factors, cell surface receptors, cell adhesion molecules, and chemokines/cytokines. Levels of the different MMPs can be measured in several sample types, including tissue, blood (serum and plasma), and urine, and using different methodologies, such as immunohistochemistry, real-time PCR, western and northern blot analyses, enzyme-linked immunosorbent assay, and zymography. Several MMPs have been identified as having potential diagnostic or prognostic utility, whether alone or in combination with cytology. Although MMP inhibitors have shown limited efficacy, advances in the understanding of the complex physiologic and pathologic roles of MMPs might permit the development of new MMP-specific and tumor-specific therapies. In this paper we update the understanding of MMPs based on a systematic PubMed search encompassing papers published up to December 2011.

Matrix metalloproteinases and their clinical relevance in urinary bladder cancer

Matrix metalloproteinases (MMPs) have important roles in several cancer-supporting cellular processes, such as extracellular matrix (ECM) remodeling, angiogenesis, apoptosis, epithelial-to-mesenchymal transition and cell proliferation. This broad range of activity has led to considerable interest in the use of MMPs in the clinical setting as diagnostic or prognostic biomarkers and as therapeutic targets. Levels of the different MMPs can be measured in several sample types, including paraffin-embedded or fresh frozen tissue, serum, plasma and urine, and by various analytical methodologies, such as immunohistochemistry, real-time PCR, western and northern blot analyses, enzyme-linked immunosorbent assay and zymography. Several MMPs have been identified as having potential diagnostic or prognostic utility, whether alone or in combination with currently available diagnostic tests or imaging modalities. Although the early broad-spectrum anti-MMP agents showed a lack of efficacy, our continually improving understanding of the complex physiologic and pathologic roles of MMPs might enable the development of new MMP-specific and tumor-specific therapies. Accordingly, MMPs will continue to be the subjects of intensive research in bladder cancer.

[Detection and molecular staging of bladder cancer using real-time RT-PCR for gelatinases (MMP-2, MMP-9) and TIMP-2 in peripheral blood]

INTRODUCTION

Molecular staging of bladder cancer based on the detection of mRNA of urothelial specific genes in circulating cancer cells has been inconclusive. We analyze whether real-time RT-PCR evaluation of gelatinases (MMP-9, MMP-2) and TIMP-2 in peripheral blood to diagnose and characterize patients with bladder neoplasm.

MATERIAL AND METHOD

Total RNA is extracted from circulating blood cells in 42 individuals (11 healthy controls, 31 patients with bladder cancer of different stages) and real-time RT-PCR performed using specific primers for MMP-9, MMP-2, TIMP-2 and ribosomal 18S. The quantification values of mRNA are described as relative to 18S mRNA (ΔΔCt method) and the results are blindly compared with data obtained from histological diagnosis and clinical staging.

RESULTS

Normalized levels of MMP-9 and MMP-2 mRNA are higher in patients with cancer than controls (1.82±0.6-fold and 2.7±0.6-fold, respectively; P<.05). Patients with metastatic disease also have increased MMP-9, MMP-2 and TIMP-2 mRNA levels (9.6±0,20-fold, 5.22±0.26-fold and 1,97±0,22-fold, respectively; P<.05). MMP-9 and MMP-2 are also associated with advanced clinical stage and grade (P<.05). A ratio between variables that increases the ability to segregate patients with Ta, T1, T2-4M0 and T2-4M1 tumours is proposed.

CONCLUSIONS

Both non-invasive bladder tumor recognition and molecular staging of the disease is possible using real-time RT-PCR-based detection of gelatinases and TIMP-2 in peripheral blood. The ability to distinguish metastatic disease is higher for MMP-9 but MMP-2 discriminates better levels of tumour invasion. Further investigation in this field could yield promising results regarding molecular evaluation of bladder neoplasia.

Plasma MMP1 and MMP8 expression in breast cancer: protective role of MMP8 against lymph node metastasis

BACKGROUND

Elevated levels of matrix metalloproteinases have been found to associate with poor prognosis in various carcinomas. This study aimed at evaluating plasma levels of MMP1, MMP8 and MMP13 as diagnostic and prognostic markers of breast cancer.

METHODS

A total of 208 breast cancer patients, of which 21 with inflammatory breast cancer, and 42 healthy controls were included. Plasma MMP1, MMP8 and MMP13 levels were measured using ELISA and correlated with clinicopathological characteristics.

RESULTS

Median plasma MMP1 levels were higher in controls than in breast cancer patients (3.45 vs. 2.01 ng/ml), while no difference was found for MMP8 (10.74 vs. 10.49 ng/ml). ROC analysis for MMP1 revealed an AUC of 0.67, sensitivity of 80% and specificity of 24% at a cut-off value of 4.24 ng/ml. Plasma MMP13 expression could not be detected. No correlation was found between MMP1 and MMP8 levels. We found a trend of lower MMP1 levels with increasing tumour size (p = 0.07); and higher MMP8 levels with premenopausal status (p = 0.06) and NPI (p = 0.04). The median plasma MMP1 (p = 0.02) and MMP8 (p = 0.007) levels in the non-inflammatory breast cancer patients were almost twice as high as those found in the inflammatory breast cancer patients. Intriguingly, plasma MMP8 levels were positively associated with lymph node involvement but showed a negative correlation with the risk of distant metastasis. Both controls and lymph node negative patients (pN0) had lower MMP8 levels than patients with moderate lymph node involvement (pN1, pN2) (p = 0.001); and showed a trend for higher MMP8 levels compared to patients with extensive lymph node involvement (pN3) and a strong predisposition to distant metastasis (p = 0.11). Based on the hypothesis that blood and tissue protein levels are in reverse association, these results suggest that MMP8 in the tumour may have a protective effect against lymph node metastasis.

CONCLUSION

In summary, we observed differences in MMP1 and MMP8 plasma levels between healthy controls and breast cancer patients as well as between breast cancer patients. Interestingly, our results suggest that MMP8 may affect the metastatic behaviour of breast cancer cells through protection against lymph node metastasis, underlining the importance of anti-target identification in drug development.