IN SITU GELATINOLYTIC ACTIVITY CORRELATES WITH TUMOR PROGRESSION AND PROGNOSIS IN PATIENTS WITH BLADDER CANCER

Prognostic Value of Membrane Type 1 and 2 Matrix Metalloproteinase Expression and Gelatinase a Activity in Bladder Cancer

Purpose

To analyze the behavior of matrix metalloproteinases (MMPs) in their active state in patients with bladder cancer.

Method

A retrospective study of 50 patients with localized bladder cancer who underwent tumor resection between June 2006 and June 2007 at the National Cancer Institute in Cairo, Egypt was carried out. Tissue samples were collected and the expression of membrane type 1 (MT1) and type 2 (MT2) MMPs was determined by Western blotting. Gelatinase A (MMP-2) activity was estimated by zymographic analysis in tissue samples of each patient and the values were correlated with clinical tumor stage and lymph node status.

Result

The behavior of MMP-2 showed statistical significance in 90% of tumor tissues compared with 22% of adjacent normal tissues (p<0.001). MT1-MMP was expressed in 88% of tumor tissues compared with 24% of normal tissues (p<0.001); MT2-MMP was expressed in 74% of tumor tissues compared with 12% of normal tissues (p<0.001). While there was a highly significant association between MMP-2 activity and MT1-MMP expression in tumor tissues (p<0.001), there was a moderately significant association between MMP-2 activity and MT2-MMP expression (p=0.018). The results also revealed an association between MT1-MMP and MT2-MMP expression in tumor tissues (p<0.001). MMP-2 activity and MT2-MMP expression in tumor tissues were statistically associated with high tumor stage (p=0.039 and p=0.014, respectively), while the expression of MT1-MMP showed no association with tumor stage (p=0.139).

Conclusion

MMP-2 activity is associated with an increase in MT2-MMP expression and with lymph node metastasis. No association was found between MT1-MMP expression and lymph node metastasis.

CD147 stimulates hepatoma cells escaping from immune surveillance of T cells by interaction with Cyclophilin A

T cells play an important role in tumor immune surveillance. CD147 is a member of immunoglobulin superfamily present on the surface of many tumor cells and mediates malignant cell behaviors. Cyclophilin A (CypA) is an intracellular protein promoting inflammation when released from cells. CypA is a natural ligand for CD147. In this study, CD147 specific short hairpin RNAs (shRNA) were transfected into murine hepatocellular carcinoma Hepa1-6 cells to assess the effects of CD147 on hepatoma cells escaping from immune surveillance of T cells. We found extracellular CypA stimulated cell proliferation through CD147 by activating ERK1/2 signaling pathway. Downregulation of CD147 expression on Hepa1-6 cells significantly suppressed tumor progression in vivo, and decreased cell viability when co-cultured with T cells in vitro. Importantly, knockdown of CD147 on Hepa1-6 cells resulted in significantly increased T cells chemotaxis induced by CypA both in vivo and in vitro. These findings provide novel mechanisms how tumor cells escaping from immune surveillance of T cells. We provide a potential therapy for hepatocellular carcinoma by targeting CD147 or CD147-CypA interactions.

MicroRNA-20b inhibits the proliferation, migration and invasion of bladder cancer EJ cells via the targeting of cell cycle regulation and Sp-1-mediated MMP-2 expression

MicroRNAs (miRs) serve either as oncogenes or tumor-suppressor genes in tumor progression. MicroRNA-20b (miR‑20b) is known to be involved with the oncomirs of several types of cancers. However, in the present study we describe how miR-20b inhibits the proliferation, migration and invasion of bladder cancer EJ cells. In the present study, miR-20b was downregulated in bladder cancer cell lines, and its overexpression resulted in a significant reduction in the proliferation of EJ cells. In addition, via a bioinformatics approach, we identified cell cycle-regulated genes that are the putative targets of miR-20b. The transfection of miR-20b into EJ cells induced G1 phase cell cycle arrest via the decreased expression of cyclin D1, CDK2 and CDK6 without affecting another G1 phase cell cycle regulator, cyclin E. The cell cycle inhibitor p21WAF1 was upregulated in the miR-20b transfected cells. Moreover, the enforced expression of miR-20b resulted in impaired wound-healing migration and invasion in the EJ cells. Based on our target prediction analysis of miRs, we confirmed that miR-20b overexpression strongly impedes MMP-2 expression via suppressive activation of the Sp-1 binding motif, an important transcription factor present in the MMP-2 promoter. Herein, we report the novel concept that miR-20b exerts a suppressive effect on both cell cycle-modulated proliferation and MMP-2-mediated migration and invasion in bladder cancer EJ cells.

Simultaneous demonstration of gelatinolytic activity, morphology, and immunohistochemical reaction using zymography film

In situ zymography has been used to assess gelatinolytic activity, which is mainly due to matrix metalloproteinases (MMPs) in cancer tissues. MMPs play an important role in cancer invasion and metastasis. Film in situ zymography (FIZ) enables the in situ evaluation of gelatinolytic activity with high reproducibility. In this article, we report a study of FIZ, in a case of breast cancer with an invasive carcinoma component showing clear gelatinolytic activity, and in a non-invasive carcinoma component showing little gelatinolytic activity. Immunohistochemistry on FIZ was also performed. The simultaneous detection of gelatinolytic activity and immunohistochemical reaction was established in a single film. Immunohistochemistry on FIZ may have good potential for the investigation of cancer microenvironment.

TG-interacting factor-induced superoxide production from NADPH oxidase contributes to the migration/invasion of urothelial carcinoma

Urothelial carcinoma (UC) of the bladder is the fourth most common cancer and the ninth leading cause of death from cancer among men in the United States. However, higher recurrence, resistance to therapy, and poor diagnostic/prognostic biomarkers of UC prompt us to identify novel targets to improve the clinical applications. TG-interacting factor (TGIF), a transcriptional corepressor to modulate the TGF-β signaling, is associated with various types of human cancer. In the present study, we found that cellular migration activity, reactive oxygen species production, AKT(S473) phosphorylation, TGIF, and p67(phox) expression were higher in invasive T24 cells than in noninvasive RT4 cells. In addition, overexpression of TGIF in RT4 cells enhanced cellular migration/invasion ability; it involved NADPH oxidase 2 (Nox2)/p67(phox) complex activation, reactive oxygen species production, and AKT(S473) phosphorylation. In contrast, the migration/invasion ability of T24 cells was suppressed by the knockdown of TGIF or p67(phox), respectively. Overexpression of AKT1 could increase cellular superoxide production and invasion. Moreover, by using the PI3K/AKT inhibitor wortmannin or shRNA of AKT1, the TGIF-induced Nox activation and superoxide production were significantly inhibited. Accordingly, we suggest that PI3K/AKT signaling mediates TGIF-induced Nox2/p67(phox) complex activation and the resultant superoxide production which reinforces the PI3K/AKT signaling to promote the cellular migration/invasion ability of UC.

The importance of integrin-linked kinase in the regulation of bladder cancer invasion

It is important to understand the molecular mechanisms of bladder cancer progression not only to prevent cancer progression but also to detect new therapeutic targets against advanced bladder cancer. The integrin-linked kinase (ILK) is a major signaling integrator in mammalian cells and plays an important role in epithelial-mesenchymal transition (EMT) of human cancers, but its mechanisms are not completely understood. In this study, we investigated the importance and mechanisms of ILK in bladder cancer progression. When the expression of ILK in bladder cancer cell lines and N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN)-induced murine bladder cancer was evaluated, ILK has a tendency to be overexpressed in invasive cell lines and invasive BBN-induced murine bladder cancer. Overexpression of ILK in 253J bladder cancer cells suppressed E-cadherin expression, resulting in the promotion of cell invasion. Conversely, ILK knockdown by siRNA suppresses cell invasion in invasive bladder cancer cells through the regulation of E-cadherin or matrix metalloprotease 9 (MMP-9). To regulate E-cadherin expression, our results showed that the glycogen synthase kinase 3β (GSK3β)-Zeb1 pathway may play an important role downstream of ILK. Finally, the results of a human bladder tissue microarray (TMA) showed that ILK expression correlates with the invasiveness of human bladder cancer. Our study suggests that ILK is overexpressed in invasive bladder cancer and plays an important role in the EMT of bladder cancer via the control of E-cadherin and MMP-9 expression. ILK may be a new molecular target to suppress tumor progression in advanced and high-risk bladder cancer patients.

BLT2 promotes the invasion and metastasis of aggressive bladder cancer cells through a reactive oxygen species-linked pathway

Aggressive bladder cancer is a major cause of morbidity and mortality. Despite the fact that metastatic disease results in death in the majority of bladder cancer cases, the molecular events regulating the invasive phenotype of aggressive bladder cancer are not well understood. In this study, immunohistochemical examination showed that the leukotriene B(4) receptor BLT2 is overexpressed in advanced malignant bladder cancers (human transitional cell carcinomas) in proportion to advancing stages, with high prognostic significance (p<0.001). Blockade of BLT2 with the specific antagonist LY255283 or siRNA knockdown significantly suppressed the invasiveness of highly aggressive 253J-BV bladder cancer cells. Moreover, our results demonstrated that BLT2 mediates invasiveness through a signaling pathway dependent on NAD(P)H oxidase (Nox) 1- and Nox4-induced generation of reactive oxygen species (ROS) and subsequent NF-kappaB stimulation. Metastasis of 253J-BV cells in mice was also dramatically suppressed by inhibition of BLT2 or its signaling. These findings suggest that a BLT2-Nox-ROS-NF-kappaB cascade plays a critical role in bladder cancer invasion and metastasis.

CD147/basigin promotes progression of malignant melanoma and other cancers

CD147/basigin, a transmembrane protein belonging to the immunoglobulin super family, was originally cloned as a carrier of Lewis X carbohydrate antigen. CD147 is strongly related to cancer progression; it is highly expressed by various cancer cells including malignant melanoma (MM) cells and it plays important roles in tumor invasiveness, metastasis, cellular proliferation, and in vascular endothelial growth factor (VEGF) production, tumor cell glycolysis, and multi-drug resistance (MDR). CD147 on cancer cells induces matrix metalloproteinase expression by neighboring fibroblasts, leading to tumor cell invasion. In a nude mouse model of pulmonary metastasis from MM, the metastatic potential of CD147-expressing MM cells injected into the tail vein is abolished by CD147 silencing. CD147 enhances cellular proliferation and VEGF production by MM cells; it promotes tumor cell glycolysis by facilitating lactate transport in combination with monocarboxylate transporters, resulting in tumor progression. CD147 is responsible for the MDR phenotype via P-glycoprotein expression. These findings strongly suggest CD147 as a possible therapeutic target for overcoming metastasis and MDR, major obstacles to the effective treatment of malignant cancers.

Bladder cancer angiogenesis and metastasis--translation from murine model to clinical trial

In the majority of cases, death from bladder cancer results from metastatic disease. Understanding the closely linked mechanisms of invasion, metastasis and angiogenesis in bladder cancer has allowed us to develop new therapeutic strategies that harbor the promise of decisive improvements in patient survival. The essential link between cell based experiments and the translation of novel agents into human patients with bladder cancer is the animal model. With emphasis on the orthotopic xenograft model, this review outlines some key mechanisms relevant to angiogenesis and the development of metastasis in bladder cancer. We highlight especially pathways related to MMP-9, IL-8, VEGF and EGFR. Most commonly, expression patterns of these markers in patients have correlated to disease progression and patient survival, which has led to laboratory investigations of these markers and eventually novel targeted therapies that are translated back into the clinic by means of clinical trials. Although imperfect in their translatability into clinical efficacy, animal models remain a critical tool in bladder cancer research.

CD147 immunoglobulin superfamily receptor function and role in pathology

The immunoglobulin superfamily member CD147 plays an important role in fetal, neuronal, lymphocyte and extracellular matrix development. Here we review the current understanding of CD147 expression and protein interactions with regard to CD147 function and its role in pathologic conditions including heart disease, Alzheimer's disease, stroke and cancer. A model linking hypoxic conditions found within the tumor microenvironment to upregulation of CD147 expression and tumor progression is introduced.

Inhibition of matrix metalloproteinase-2 secretion and invasion by human ovarian cancer cell line SK-OV-3 with lysine, proline, arginine, ascorbic acid and green tea extract

AIMS

Based on the poor prognosis associated with ovarian cancer and reported anticancer properties of specific nutrients, we investigated the effect of a nutrient mixture (NM) containing lysine, proline, arginine, ascorbic acid and epigallocatechin gallate on human ovarian cancer cells SK-OV-3 by measuring: cell proliferation, modulation of matrix metalloproteinase (MMP)-2 and -9 expression, and cancer cell invasive potential.

METHODS

Cell proliferation was evaluated by MTT assay, MMP activity by gelatinase zymography, and invasion through Matrigel.

RESULTS

Human ovarian cancer cell growth was not significantly affected by the NM. Zymography demonstrated inhibition of MMP-2 secretion in a dose-dependent fashion with virtual total inhibition at 50 microg/mL NM concentration. Invasion of human ovarian cancer cells through Matrigel decreased in a dose-dependent fashion, with 90% inhibition at 500 microg/mL NM and 100% inhibition at 1000 microg/mL NM (P < 0.0001).

CONCLUSION

The combination of lysine, proline, arginine, ascorbic acid and green tea extract tested inhibited critical steps in cancer development and spread, such as MMP expression and invasion, indicating its potential as a treatment modality against ovarian cancer.

Suppression of human cervical cancer cell lines Hela and DoTc2 4510 by a mixture of lysine, proline, ascorbic acid, and green tea extract

Cervical cancer, the second most common cancer in women, once metastasized, leads to poor prognosis. We investigated the antitumor effect of a nutrient mixture (NM) containing lysine, proline, arginine, ascorbic acid, and green tea extract on human cervical cancer cells Hela (CCL-2) and DoTc2 4510 by measuring cell proliferation (MTT assay), modulation of matrix metalloproteinases (MMP)-2 and MMP-9) expression (gelatinase zymography), and cancer cell invasive potential (Matrigel). NM showed significant antiproliferative effect on CCL-2 and DoTc2 4510 cancer cells. The NM inhibited CCL-2 expression of MMP-2 and MMP-9 in a dose-dependent fashion, with virtual total inhibition of MMP-2 at 1000 microg/mL and MMP-9 at 500 microg/mL NM. Untreated DoTc2 4510 cells showed MMP-9 expression, which was enhanced with phorbol 12-myristate 13-acetate treatment. NM inhibited MMP-9 expression in a dose-dependent fashion, with virtual inhibition at 500 microg/mL. Invasion of human cervical cancer cells CCL-2 and DoTc2 4510 through Matrigel decreased in a dose-dependent fashion, with 100% inhibition at 500 microg/mL NM (P < 0.0001) and 1000 microg/mL NM (P < 0.0001), respectively. Our results suggest that the mixture of lysine, proline, arginine, ascorbic acid, and green tea extract has potential in the treatment of cervical cancer by inhibiting critical steps in cancer development and spread.

The activity of matrix metalloproteinases (MMPS) and tissue inhibitors of metalloproteinases (TIMPs) in mammary tumors of dogs and rats

We conducted zymography for detecting the activity of matrix metalloproteinases (MMPs) and reverse zymography for the activity of tissue inhibitors of metalloproteinases (TIMPs) in canine spontaneous and rat 7, 12-dimethylbenz(a)anthracene (DMBA)-induced mammary tumor tissues. The activities of MMPs of canine mammary tumors were quite higher than those of the rat chemically induced tumors. The activities of MMPs were significantly higher in malignant tissues than in benign ones of canine tumors, whereas the activity of only MMP-2 was higher in both benign and malignant rat tumors compared to normal tissues. There were no differences of MMPs activities between benign and malignant rat tumors. The results of reverse zymography indicated that the activities of TIMP-1, -2 and -3 were strikingly higher in rat tumors than in canine tumors. The activities were higher in malignant tissues than in benign ones of dogs, and higher in tumor tissues than in normal mammary tissues of rats. The results of film in situ zymography for tissue localization of gelatinolytic activity showed that the digested area was more extended in malignant tumors than in benign ones of dogs. However, the area was similarly extended in both benign and malignant rat tumors. These results may indicate that the canine spontaneous malignant mammary tumors possess more aggressive nature than the rat chemically induced counterpart, resulting from the high level of MMPs and low level of TIMPs activities of the tumor tissues.

Local proteolytic activity in tumor cell invasion and metastasis

Proteolytic cleavage of extracellular matrix (ECM) is a critical regulator of many physiological and pathological events. It affects fundamental processes such as cell growth, differentiation, apoptosis and migration. Most proteases are produced as inactive proenzymes that undergo proteolytic cleavage for activation. Proteolytic activity is additionally modified by endogenous inhibitors. Mechanisms that localize and concentrate protease activity in the pericellular microenvironment of cells are prerequisites for processes like angiogenesis, bone development, inflammation and tumor cell invasion. Methods that enable real-time, high-resolution imaging and precise quantification of local proteolytic activity in vitro and in vivo remain major challenges. These methods will play an important role in the understanding of basic principles e.g. in cancer cell invasion, the identification of new therapeutical targets and hence drug design. This review highlights mechanisms and functions of local proteolytic activity with special emphasis on tumor cell invasion and metastasis, and focuses on techniques for the investigation of this process.