Enhanced Expression but Decreased Specific Activity of Matrix Metalloproteinase 10 (MMP-10) in Comparison with Matrix Metalloproteinase 3 (MMP-3) in Human Urinary Bladder Carcinoma

The Significance of Matrix Metalloproteinase 9 (MMP-9) and Metalloproteinase 2 (MMP-2) in Urinary Bladder Cancer

INTRODUCTION

Urinary bladder cancer is a serious oncological problem that is the cause of many deaths worldwide. The processes of metastasis and origination of local tumor invasion depend on the extracellular matrix (ECM) degradation. The cancer microenvironment, particularly the ECM, may be considered a key factor in cancer progression. Matrix metalloproteinases (MMPs) are classified as the main factors responsible for the degradation of ECM components. Therefore, the aim of the study was to evaluate the expression and activity of matrix metalloproteinase 2 and 9 (MMP-2 and MMP-9) in urinary bladder cancer according to different stages.

MATERIAL AND METHODS

Urinary bladder tissue samples were analyzed. Cancer patients were divided into two groups: low-grade tumors (LG; Group I) and high-grade tumors (HG; Group II). Control tissue was obtained from the opposite site to the tumor. MMPs content and activity (actual and specific) were evaluated using ELISA and Western blot methods, respectively.

RESULTS

Both MMPs are present in high and low molecular complexes in healthy or bladder cancer tissues. The content of MMP-9 is enhanced in comparison with MMP-2, particularly in HG cancer tissue. The actual activity of MMP-2 was highest in LG cancer tissue whereas the actual activity of MMP-9 was highest in HG cancer. Specific activity of both MMPs was highest in LG cancer, but the activity of MMP-9 was higher in comparison with MMP-2.

CONCLUSIONS

In conclusion, the content and specific activity of MMP-9 were increased in comparison with MMP-2. The revealed differences in content and activity of both MMPs demonstrate their different participation in ECM remodeling at different stages of cancer development. Moreover, it seems that MMP-9 has higher clinical utility than MMP-2 as a potential therapeutic option and a diagnostic biomarker of urinary bladder cancer.

Higher Content but Not Activity of Stromelysin-2 (MMP-10) in Comparison to Stromelysin-1 (MMP-3) in Human Renal Carcinoma

Stromelysin-1 and stromelysin-2 (matrix metalloproteinase 3; MMP-3 and matrix metalloproteinase 10; MMP-10, respectively) are enzymes that activate other metalloproteinases. Apart from collagen, they also degrade elastin, fibronectin, gelatin and laminin. In carcinogenic processes, they are involved in angiogenesis and metastasis. Therefore, the aim of this study was to evaluate the DNA content, expression and activity of both stromelysines in cancers of human kidney. Renal carcinoma tissue samples were analyzed. Low- and high-grade cancer tissues were collected. Control material was collected from part of the kidney opposite to the tumor. DNA content, stromelysines content and stromelysin-1 and stromelysin-2 activity were measured using ELISA and Western blot methods. A higher content of deoxyribonucleic acid in low- and high-grade cancer tissues in comparison to the respective control tissue was observed. Both stromelysines were presented in control and cancer tissues in high-molecular-weight complexes. The content of MMP-10 was significantly higher in comparison to MMP-3 in all investigated tissues. Moreover, the content of stromelysin-2 was significantly higher in high-grade (G3) tissues compared to grade 2 (G2) kidney cancer. A significant decrease in the actual and specific activities of both stromelysines was observed with the increase in renal cancer grade. The presented results may indicate that the degradation of extracellular matrix increases with a higher grade of cancer. Moreover, the elevated content and decreased specific activity of stromelysin-2 in cancer tissue indicate that MMP-10 is mainly present in an inactive form in renal carcinoma. Detailed knowledge of the mechanism and participation of stromelysines in extracellular matrix degradation may be important in understanding the pathomechanism of renal cancer development. Therefore, the potential application of stromelysines in the monitoring or prognosis of kidney cancer should be discussed.

Gardnerella Exposures Alter Bladder Gene Expression and Augment Uropathogenic Escherichia coli Urinary Tract Infection in Mice

The anaerobic actinobacterium Gardnerella was first isolated from the bladder by suprapubic aspiration more than 50 years ago. Since then, Gardnerella has been increasingly recognized as a common and often abundant member of the female urinary microbiome (urobiome). Some studies even suggest that the presence of Gardnerella is associated with urological disorders in women. We recently reported that inoculation of Gardnerella into the bladders of mice results in urothelial exfoliation. Here, we performed whole bladder RNA-seq in our mouse model to identify additional host pathways involved in the response to Gardnerella bladder exposure. The transcriptional response to Gardnerella reflected the urothelial turnover that is a consequence of exfoliation while also illustrating the activation of pathways involved in inflammation and immunity. Additional timed exposure experiments in mice provided further evidence of a potentially clinically relevant consequence of bladder exposure to Gardnerella-increased susceptibility to subsequent UTI caused by uropathogenic Escherichia coli. Together, these data provide a broader picture of the bladder's response to Gardnerella and lay the groundwork for future studies examining the impact of Gardnerella on bladder health.

DNA Methylome Changes of Muscle- and Neuronal-Related Processes Precede Bladder Cancer Invasiveness

Bladder cancer (BC) is the ninth leading cause of cancer death with one of the highest recurrence rates among all cancers. One of the main risks for BC development is exposure to nitrosamines present in tobacco smoke or in other products. Aberrant epigenetic (DNA methylation) changes accompanied by deregulated gene expression are an important element of cancer pathogenesis. Therefore, we aimed to determine DNA methylation signatures and their impacts on gene expression in mice treated with N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN), a carcinogen similar to compounds found in tobacco smoke. Following BBN administration mice developed non-invasive or invasive bladder cancers. Surprisingly, muscle- and neuronal-related pathways emerged as the most affected in those tumors. Hypo- and hypermethylation changes were present within non-invasive BC, across CpGs mapping to the genes involved in muscle- and neuronal-related pathways, however, methylation differences were not sufficient to affect the expression of the majority of associated genes. Conversely, invasive tumors displayed hypermethylation changes that were linked with alterations in gene expression profiles. Together, these findings indicate that bladder cancer progression could be revealed through methylation profiling at the pre-invasive cancer stage that could assist monitoring of cancer patients and guide novel therapeutic approaches.