Localization and quantification of mRNA for matrix metalloproteinase-2 (MMP-2) and tissue inhibitor of matrix metalloproteinase-2 (TIMP-2) in human benign and malignant prostatic tissue

Metalloproteinase 9 immunostaining profile is positively correlated with tumor grade, extraprostatic extension and biochemical recurrence in prostate cancer

Metastasis is the main problem in the treatment of prostate cancer (PCa), and for it to occur, proteolytic enzymes must remodel the extracellular matrix (ECM) surrounding the tumor. The most important group of enzymes with this action include the matrix metalloproteinases (MMPs), which act on various substrates cleaving ECM components. The present study aimed to evaluate the protein immunostaining profiles of matrix metalloproteinase 2 (MMP-2) and 9 (MMP-9) in PCa Brazilian patients using the indirect immunohistochemical methodology. The tissue samples (n = 178), 60 from malignant tumor, 58 from adjacent non-tumor, and 60 from ECM, were evaluated according to the immunostaining intensity. The malignant tumor cytoplasmic MMP-2 immunostaining was more intense than in ECM (p = 0.001), but it did not correlate with any clinical-pathological parameter. The MMP-9 staining was similar in tumor cytoplasm, adjacent non-tumor cytoplasm and ECM, but showed significant positive correlations with ISUP grade (p = 0.044; Tau=0.249), extraprostatic extension (p = 0.025; Tau=0.309), and biochemical recurrence (p = 0.048; Tau=0.306). A significant positive correlation was also observed between MMP-2 and MMP-9 in all cell compartments analyzed. Although further research is warranted to elucidate the precise mechanisms underlying these observations, our findings suggest MMP-9 as a promising candidate marker for tissue invasion that could be used in predicting the progression and prognosis of PCa.

The Role of the Metzincin Superfamily in Prostate Cancer Progression: A Systematic-Like Review

Prostate cancer remains a leading cause of cancer-related morbidity in men. Potentially important regulators of prostate cancer progression are members of the metzincin superfamily of proteases, principally through their regulation of the extracellular matrix. It is therefore timely to review the role of the metzincin superfamily in prostate cancer and its progression to better understand their involvement in this disease. A systematic-like search strategy was conducted. Articles that investigated the roles of members of the metzincin superfamily and their key regulators in prostate cancer were included. The extracted articles were synthesized and data presented in tabular and narrative forms. Two hundred and five studies met the inclusion criteria. Of these, 138 investigated the role of the Matrix Metalloproteinase (MMP) subgroup, 34 the Membrane-Tethered Matrix Metalloproteinase (MT-MMP) subgroup, 22 the A Disintegrin and Metalloproteinase (ADAM) subgroup, 8 the A Disintegrin and Metalloproteinase with Thrombospondin Motifs (ADAMTS) subgroup and 53 the Tissue Inhibitor of Metalloproteinases (TIMP) family of regulators, noting that several studies investigated multiple family members. There was clear evidence that specific members of the metzincin superfamily are involved in prostate cancer progression, which can be either in a positive or negative manner. However, further understanding of their mechanisms of action and how they may be used as prognostic indicators or molecular targets is required.

Spirit-Quieting Traditional Chinese Medicine may Improve Survival in Prostate Cancer Patients with Depression

Depression is associated with higher mortality in prostate cancer. However, whether traditional Chinese medicine (TCM) for depression improves outcomes in patients with prostate cancer is unclear. This retrospective cohort study evaluated the association between TCM for depression and mortality in patients with prostate cancer. During the period 1998⁻2012, a total of 248 prostate cancer patients in Taiwan with depression were enrolled and divided into three groups: TCM for depression (n = 81, 32.7%), TCM for other purposes (n = 53, 21.3%), and no TCM (n = 114, 46.0%). During a median follow-up of 6.2 years, 12 (14.8%), 13 (24.5%), and 36 (31.6%) deaths occurred in the TCM for depression, TCM for other purposes, and no TCM groups, respectively. After adjusting age at diagnosis, urbanization, insured amount, comorbidity disease, and prostate cancer type, TCM for depression was associated with a significantly lower risk of overall mortality based on a multivariate-adjusted Cox proportional-hazards model (hazard ratio 0.42, 95% confidence interval: 0.21⁻0.85, p = 0.02) and Kaplan⁻Meier survival curve (log-rank test, p = 0.0055) compared to no TCM. In conclusion, TCM for depression may have a positive association with the survival of prostate cancer patients with depression.

miR-618: possible control over TIMP-1 and its expression in localized prostate cancer

BACKGROUND

The imbalance between the action of the tissue inhibitors of matrix metalloproteinases (TIMPs) and the matrix metalloproteinases (MMPs) is one component of metastasis physiology. TIMP-1 overrides MMP-9 activity in cancer and might be regulated by miR-618. The aims of this study were to clarify whether TIMP-1 expression is modified by miR-618 and to clarify the effect of miR-618 expression on the invasion of prostate cancer cells. We also studied miR-618 expression in surgical specimens of patients with localized prostate cancer submitted to open radical prostatectomy.

METHODS

After transfection of miR-618 or its antagonist in DU145 cells, qRT-PCR for TIMP-1/MMP-9 and both ELISA and zymography for MMP-9 were performed. Total miRNA was extracted from surgical specimens of PCa, and miR-618 expression was examined for correlations with Gleason score, pathological status and biochemical recurrence.

RESULTS

DU145 cells transfected with miR-618 had a 76% reduction in TIMP-1 expression relative to control cells (p = 0.003). miR-618 inhibition reduced MMP-9 expression by 31% (p = 0.032) and MMP-9 absorbance evaluated with ELISA assay (p = 0.06).Zymography suggested higher MMP-9 activity in DU145 cells transfected with miR-618 than those transfected with miR-618 inhibitor, but the difference was not significant (p = 0.55). However, miR-618 expression was lower in surgical specimens of patients with Gleason score > 7 (p = 0.08) and more advanced disease (p = 0.07).

CONCLUSIONS

In vitro, miR-618 overexpression decreases TIMP-1 and miR-618 inhibition decreases MMP-9, suggesting that miR-618 might be an oncomiR. However, the analysis of clinical samples of localized prostate cancer revealed an inconsistent pattern, as increased miR-618 expression was associated with lower Gleason score and pathological status. Further studies are needed to address whether miR-618 is a context-dependent miRNA.

Matrix Metalloproteinases: A challenging paradigm of cancer management

Matrix metalloproteinases (MMPs) are members of zinc-dependent endopeptidases implicated in a variety of physiological and pathological processes. Over the decades, MMPs have been studied for their role in cancer progression, migration, and metastasis. As a result, accumulated evidence of MMPs incriminating role has made them an attractive therapeutic target. Early generations of broad-spectrum MMP inhibitors exhibited potent inhibitory activities, which subsequently led to clinical trials. Unexpectedly, these trials failed to meet the desired goals, mainly due to the lack of efficacy, poor oral bioavailability, and toxicity. In this review, we discuss the regulatory role of MMPs in cancer progression, current strategies in targeting MMPs for cancer treatment including prodrug design and tumor imaging, and therapeutic value of MMPs as biomarkers in breast, lung, and prostate cancers.

Expression and prognostic impact of matrix metalloproteinase-2 (MMP-2) in astrocytomas

Astrocytomas are the most frequent primary brain tumors in adults, and despite aggressive treatment patients often experience recurrence. Survival decreases with increasing tumor grade, and especially patients with grade IV glioblastoma have poor prognosis due to the aggressive character of this tumor. Matrix metalloproteinase-2 (MMP-2) is an extracellular matrix degrading enzyme which has been shown to play important roles in different cancers. The aim of this study was to investigate the expression and prognostic potential of MMP-2 in astrocytomas. Tissue samples from 89 patients diagnosed with diffuse astrocytoma, anaplastic astrocytoma and glioblastoma were stained immunohistochemically using a monoclonal MMP-2 antibody. The MMP-2 intensity in cytoplasm/membrane was quantified by a trained software-based classifier using systematic random sampling in 10% of the tumor area. We found MMP-2 expression in tumor cells and blood vessels. Measurements of MMP-2 intensity increased with tumor grade, and MMP-2 expression was found to be significantly higher in glioblastomas compared to normal brain tissue (p<0.001), diffuse astrocytomas (p<0.001) and anaplastic astrocytomas (p<0.05). MMP-2 expression was associated with shorter overall survival in patients with grade II-IV astrocytic tumors (HR 1.60; 95% CI 1.03–2.48; p = 0.036). In glioblastoma, high MMP-2 was associated with poorer prognosis in patients who survived longer than 8.5 months independent of age and gender (HR 2.27; 95% CI 1.07–4.81; p = 0.033). We found a positive correlation between MMP-2 and tissue inhibitor of metalloproteinases-1 (TIMP-1), and combined MMP-2 and TIMP-1 had stronger prognostic value than MMP-2 alone also when adjusting for age and gender (HR 2.78; 95% CI 1.30–5.92; p = 0.008). These findings were validated in bioinformatics databases. In conclusion, this study indicates that MMP-2 is associated with aggressiveness in astrocytomas and may hold an unfavorable prognostic value in patients with glioblastoma.

Complementary traditional Chinese medicine therapy improves survival in patients with metastatic prostate cancer

More than 50% of prostate cancer patients have used traditional Chinese medicine (TCM) in Taiwan. However, the long-term clinical efficacy of TCM in prostate cancer patients remains unclear. Here, we investigated the relationship between TCM use and the survival of prostate cancer patients.A retrospective nationwide cohort study of prostate cancer patients was conducted between 1998 and 2003 using the Taiwan National Health Insurance Research Database. Patients were classified as TCM users or nonusers, and monitored from the day of prostate cancer diagnosis to death or end of 2012. The association between death risk and TCM use was determined using Cox proportional-hazards models and Kaplan-Meier curves.Of the 1132 selected prostate cancer patients, 730 (64.5%) and 402 (35.5%) were TCM users and nonusers, respectively. The mean follow-up period was 8.38 years, and 292 (25.8%) deaths were reported. TCM users had a decreased mortality rate (21.9%) compared with nonusers (32.8%). A lower death risk was observed with longer TCM use, especially in patients who used TCM for ≧200 days (adjusted hazard ratio [aHR] 0.61, 95% confidence interval [CI] 0.44-0.84). TCM users with metastatic prostate cancer had a significant lower HR than nonusers (aHR 0.70, 95% CI 0.51-0.95). Chai-Hu-Jia-Long-Gu-Mu-Li-Tang was the most significant TCM formulae for improving survival in metastatic prostate cancer (aHR 0.18, 95% CI 0.04-0.94).The result suggested that complementary TCM therapy might be associated with a reduced risk of death in metastatic prostate cancer patients.

Roles of matrix metalloproteinases and their natural inhibitors in prostate cancer progression

Matrix metalloproteinases (MMPs), a group of zinc-dependent endopeptidases involved in the degradation of the extracellular matrix, play an important role in tissue remodeling associated with various physiological processes such as morphogenesis, angiogenesis, and tissue repair, as well as pathological processes including cirrhosis, arthritis and cancer. The MMPs are well established as mediators of tumor invasion and metastasis by breaking down connective tissue barriers. Although there has been a vast amount of literature on the role of MMPs in invasion, metastasis and angiogenesis of various cancers, the role of these endopeptidases in prostate cancer progression has not been systematically reviewed. This overview summarizes findings on the tissue and blood expression of MMPs, their function, regulation and prognostic implication in human prostate cancer, with a focus on MMP-2, -7, -9, MT1-MMP and tissue inhibitor of metalloproteinase 1 (TIMP-1). This review also summarizes the efficacy and failure of early-generation matrix metalloproteinase inhibitors (MMPIs) in the treatment of metastatic prostate cancer and highlights the lessons and challenges for next generation MMPIs.

O-phenyl carbamate and phenyl urea thiiranes as selective matrix metalloproteinase-2 inhibitors that cross the blood-brain barrier

Brain metastasis occurs in 20-40% of cancer patients. Treatment is mostly palliative, and the inability of most drugs to penetrate the brain presents one of the greatest challenges in the development of therapeutics for brain metastasis. Matrix metalloproteinase-2 (MMP-2) plays important roles in invasion and vascularization of the central nervous system and represents a potential target for treatment of brain metastasis. Carbonate, O-phenyl carbamate, urea, and N-phenyl carbamate derivatives of SB-3CT, a selective and potent gelatinase inhibitor, were synthesized and evaluated. The O-phenyl carbamate and urea variants were selective and potent inhibitors of MMP-2. Carbamate 5b was metabolized to the potent gelatinase inhibitor 2, which was present at therapeutic concentrations in the brain. In contrast, phenyl urea 6b crossed the blood-brain barrier, however, higher doses would result in therapeutic brain concentrations. Carbamate 5b and urea 6b show potential for intervention of MMP-2-dependent diseases such as brain metastasis.

Matrix metalloproteinases and angiogenic factors: predictors of survival after radical prostatectomy for clinically organ-confined prostate cancer?

The aim of the present study was to investigate whether biomarkers improve the prediction of recurrence-free, disease-specific, and overall survival in patients with clinically localized prostate cancer. A tissue microarray was constructed from prostate specimens of 278 patients who underwent open radical retropubic prostatectomy for clinically localized prostate cancer. For immunohistochemical studies, antibodies were used against matrix metalloproteinase (MMP)-2, MMP-3, MMP-7, MMP-9, MMP-13, and MMP-19, as well as against vascular endothelial growth factor, hypoxia-induced factor 1α, basic fibroblast growth factor, and cluster of differentiation 31. Univariate and multivariable analyses were performed to evaluate the potential predictors of overall, disease-specific, and recurrence-free survival. In univariate analysis of patients with clinically organ-confined prostate cancer, only higher expression levels of MMP-9 (hazard ratio [0.6], 95% CI 0.45-0.8) had a protective effect in terms of overall survival. This positive effect of high MMP-9 expression was also observed for recurrence-free (HR 0.88, 95% CI 0.78-0.99) and disease-specific survival (HR 0.5, 95% CI 0.36-0.73). In multivariable analysis, none of these potential markers was found to be an independent prognostic factor of survival. Of all MMPs and angiogenic factors tested, MMP-9 expression has the potential as a prognostic marker in patients undergoing radical prostatectomy for clinically organ-confined cases of prostate cancer.

Clinical and biological significance of CXCR5 expressed by prostate cancer specimens and cell lines

Chemokines and chemokine receptors have been shown to be involved in metastatic process of prostate cancer (PCa). In this study, we show primary PCa tissues and cell lines (LNCaP and PC3) express CXCR5, a specific chemokine receptor for CXCL13. Expression of CXCR5 was significantly higher (p < 0.001) in PCa cases than compared to normal match (NM) tissues. CXCR5 intensity correlated (R(2) = 0.97) with Gleason score. While prostate tumor tissues with Gleason scores >or= 7, displayed predominantly nuclear CXCR5 expression patterns, PCa specimens with Gleason scores <or= 6 showed predominantly membrane and cytoplasmic expression patterns that were comparable to benign prostatic hyperplasia (BPH). Similar to tissue expression, PCa cell lines expressed significantly more CXCR5 than normal prostatic epithelial cells (PrECs), and CXCR5 expression was distributed among intracellular and extracellular compartments. Functional in vitro assays showed higher migratory and invasive potentials toward CXCL13, an effect that was mediated by CXCR5. In both PCa cell lines, CXCL13 treatment increased the expression of collagenase-1 or matrix metalloproteinase-1 (MMP-1), collagenase-3 (MMP-13), stromelysin-1 (MMP-3), stromelysin-2 (MMP-10) and stromelysin-3 (MMP-11). These data demonstrate the clinical and biological relevance of the CXCL13-CXCR5 pathway and its role in PCa cell invasion and migration.

The ratio of matrix metalloproteinase to E-cadherin expression: a pilot study to assess mRNA and protein expression among African American prostate cancer patients

BACKGROUND

We assessed the expression of Matrix Metalloproteinase (MMP) to E-cadherin (M/E ratio) to determine the correlation of gene expression with pathologic variables and outcome in a cohort of African American (AA) prostate cancer patients.

METHODS

Tumors from formalin-fixed, paraffin embedded RP specimens were examined. Gleason scores were 6, 7, and >or=8 in 7, 16, 13 tumors, respectively. Pathologic stage was organ confined (pT2) in 18 and advanced (>pT2) in 18 tumors. A colorimetric mRNA in situ hybridization (ISH) assay was performed using biotinylated anti-sense oligonucleotide probes for MMP 2 and 9, as well as for E-cadherin gene transcripts. Immunohistochemistry (IHC) was performed utilizing specific monoclonal antibodies to detect the above genes. Image analysis was performed to determine the intensity of both mRNA and protein expression. Two reviewers analyzed ISH gene expression independently.

RESULTS

The M/E expression ratio was significantly increased at the invasive edge (but not the center) of tumors of higher Gleason score (P = 0.02 and 0.0008) and pathologic stage (P = 0.0001 and <0.0001) when examined by both ISH and IHC. Significant variability in ISH staining interpretation was noted within and among the two study reviewers. An M/E ratio >2.5 was associated with biochemical recurrence after radical prostatectomy in addition to tumor pathologic stage subsequent to univariate statistical analysis.

CONCLUSIONS

The M/E ratio characterizes an important aspect of the molecular phenotype associated with the histologic progression of prostate cancer among African American prostate cancer patients. A larger comparative study is required to determine potential racial variation and prognostic significance of gene expression.

BMP-6 over-expression in prostate cancer is associated with increased Id-1 protein and a more invasive phenotype

Bone morphogenetic protein-6 (BMP-6) has been strongly implicated in prostate cancer development and bone metastasis. Our previous data showed that BMP-6 mRNA was absent in patients with benign prostatic hyperplasia, but evident in primary tumours with established secondary skeletal metastases. To examine the role of BMP-6 in prostate cancer progression, we have developed a BMP-6-regulatable, doxycycline-inducible gene expression system. BMP-6 induction by doxycycline addition led to increased levels of BMP-6 RNA and protein, associated with nuclear translocation of SMADs and activation of the downstream target gene Id-1. BMP-6 protein did not enhance the proliferation rate of PC3M cells but did significantly increase the rate of migration and invasion in both PC3M and DU145 cells. Increased metalloproteinase (MMP-1 and MMP-9) mRNA levels were also observed following BMP-6 induction. Luciferase reporter assays confirmed BMP-6-mediated activation of MMP-1 and MMP-9 promoters, indicating direct transcriptional activation of MMPs by BMP-6. BMP-6 stimulation also led to an increase in phosphorylation levels of MAPK proteins. We next examined the effects of BMP-6 on the downstream gene Id-1 in a cohort of prostate cancer patients. A tissue microarray (TMA) was constructed and samples stained for BMP-6 and Id-1 expression. We observed a significant increase in the intensity of staining of epithelial BMP-6 in the cancer cases compared to the benign cases (Mann-Whitney U test, p < 0.0005) and in the intensity of staining of epithelial Id-1 in the cancer cases compared to the benign cases (Mann-Whitney U test, p = 0.015). We further observed a significant positive correlation between epithelial staining for Id-1 and BMP-6 (p = 0.001) across all samples for both benign and cancer cases. These data demonstrate that BMP-6 promotes migration and invasion of prostate cancer cells, potentially through activation of Id-1 and MMP activation.

Brain derived metastatic prostate cancer DU-145 cells are effectively inhibited in vitro by guava (Psidium gujava L.) leaf extracts

The aqueous extract of Psidium guajava L. (PE) inhibited the cancer cell DU-145 in a dose- and time-dependent manner. At 1.0 mg/mL, PE reduced the viability of PCa DU-145 (the androgen independent PCa cells) to 36.1 and 3.59%, respectively after 48 h and 72 h of incubations. The absolute cell viability suppressing capability (VSC)(AC) could reach 262.5 cells-mL-h/mg on exposure to PE for 72 h, corresponding to the safe ranges, i.e. the percent viability suppressing rates (PVSR) of 2.72 and 2.41 folds for DU-145 comparing to PZ-HPV-7 cells when treated with PE at 0.5 and 1.0 mg/mL respectively for 72 h. In addition, the colony forming capability of DU-145 cells was apparently lowered. The suppressing rates of which reached 8.09 and 5.96 colony/mg/day for D-145 and PZ-HPV-7 cells, respectively within the concentration range of PE at 0.1 asymptotically equal to 0.25 mg/mL. Cell cycle arrests at G0/G1 phase in both cells were observed by TUNEL assay and flow cytometric analysis, yet more prominently evident in DU-145. In addition, suppression of the matrix metalloproteinases MMP-2 and MMP-9, and the upregulation of active caspase-3 at 0.10 to 1.0 mg/mL in DU-145 were also effected in a dose-dependent manner by PE at 0.25 to 1.0 mg/mL, implicating a potent anti-metastasis power of PE. Conclusively, we ascribe the anticancer activity of PE to its extraordinarily high polyphenolic (165.61 +/- 10.39 mg/g) and flavonoid (82.85 +/- 0.22 mg/g) contents. Furthermore, PE might be useful for treatment of brain derived metastatic cancers such as DU-145, acting simultaneously as both a chemopreventive and a chemotherapeutic.

Influence of genistein isoflavone on matrix metalloproteinase-2 expression in prostate cancer cells

We investigated the expression of matrix metalloproteinase (MMP)-2 in human LNCaP and PC3 prostate cancer cell lines in response to genistein exposure. Initially we studied the phytosensitivity of the cells to genistein using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay to determine percentage cell viability/inhibition and the terminal deoxynucleotidyl transferase-mediated fluorescein-dUTP nick end-labeling apoptosis assay to assess the type of cell death. The results revealed that genistein inhibited growth and proliferation in both PC3 (hormone-dependent) and LNCaP (hormone-independent) prostate cancer cell lines, that there was no significant difference in sensitivity to genistein between PC3 and LNCaP cells, and that the effect of genistein on the cells was dose- and time-dependent. The results also revealed that inhibition of cell growth in both PC3 and LNCaP cells was predominantly due to apoptotic cell death. These results were consistent with data in previous studies. This was followed by determination of the MMP-2 profile in response to genistein treatment. The results indicated a significant dose- and time-dependent inhibition of MMP-2 expression levels in both cells, with a highly significant negative correlation between MMP-2 levels and concentration of genistein. This is of phytotherapeutic significance in view of the pivotal role of MMP-2 expression in the pathogenesis of prostate cancer. Increasing expression of MMPs has been identified in many human cancers, including prostate cancer. Our findings indicate that genistein could be a potent therapeutic inhibitor of MMP-2 in line with current concepts of targeted treatment.

Terazosin Modifies the Content of Glycosaminoglycans and the Activity of Matrix Metalloproteinase 2 in the Rat Ventral Prostate

OBJECTIVES

We have investigated the effects of terazosin on the content of glycosaminoglycans (GAGs), the activity of matrix metalloproteinase 2 (MMP-2) and MMP-9, and the content of tissue inhibitors of MMP (TIMP) in the ventral prostate of Wistar rats.

METHODS

Rats were treated with terazosin (0.12, 1.2mg/kg orally every second day) for 120 d. GAGs were isolated and purified from ventral prostate homogenates by lipid extraction, ethanol precipitation, and extensive digestion with pronase and DNAse, separated by electrophoresis, and characterised using specific enzymes. The activity of MMP-2 and MMP-9 was estimated using gelatin zymography and TIMP-1 and TIMP-2 were measured by enzyme-linked immunosorbent assay.

RESULTS

Terazosin treatment did not affect the weight of the ventral prostate gland. The prostate contains hyaluronic acid, chondroitin sulfate (CS), dermatan sulfate (DS), and heparan sulfate (HS), MMP-2, TIMP-1, and TIMP-2, but not MMP-9. Terazosin caused a significant increase in the relative content of DS and a significant decrease in the relative content of CS and to a lesser extent of HS. Terazosin evoked a significant increase in the activity of proMMP-2 and MMP-2 but did not affect TIMP.

CONCLUSIONS

The differential effect of terazosin treatment in GAG molecules of the rat prostate may be beneficial because CS is known to induce and DS to inhibit cell proliferation. The effect of terazosin on GAGs and MMP-2 may contribute in the molecular mechanisms of terazosin-induced apoptosis because HS and CS have a proapoptotic effect, whereas DS and MMP-2 are antiapoptotic.

The role of matrix metalloproteinases-2, -7 and -9 and ?-catenin in high grade endometrial carcinoma

AIMS

To determine the expression of matrix metalloproteinases (MMPs)-2, -7 and -9 and beta-catenin in uterine serous carcinoma (USC) and endometrioid endometrial carcinoma (EEC) and to investigate any difference in expression between EEC and USC which might explain the mechanism of invasion and aggressive behaviour of USC.

METHODS AND RESULTS

Tissue microarrays were created from the viable central part and from the invasive edge of 20 cases of grade 3 EEC and 73 cases of USC. Immunohistochemistry was performed using antibodies to MMPs-2, -7 and -9 and beta-catenin. MMPs-2, -7 and -9 and beta-catenin were present in both tumour types; there was significantly higher expression of MMPs-2 and -9 in EEC compared with USC and significantly increased expression of MMPs-2 and -9 by carcinoma cells at the invasive edge of USC.

CONCLUSIONS

MMPs-2, -7 and -9 and beta-catenin are present in EEC and USC. The increased expression of MMPs-2 and -9 by carcinoma cells at the invasive edge of USC is possibly due to increased binding of MMPs secreted by the stromal cells to carcinoma cells, thus equipping the USC carcinoma cells with proteases for invasion.

Depsipeptide a histone deacetlyase inhibitor down regulates levels of matrix metalloproteinases 2 and 9 mRNA and protein expressions in lung cancer cells (A549)

BACKGROUND

A novel histone deacetylase inhibitor, depsipeptide FR901228 (FK228), is a promising anticancer and antiproliferative agent and has been proposed to regulate gene transcription and reported to lower the risk of several cancers in different cell lines. Depsipeptide showed therapeutic efficacy in Phase I trial of patients with malignant lymphoma. Based on the recognition that basement membrane disruption occurs in acute lung injury and that matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9) can degrade type IV collagen, one of the major components of the basement membrane and known to involve in tumor invasion and metastases. We hypothesized that depsipeptide would modulate MMP-2 and MMP-9 production in lung adenocarcinoma cells line (A549).

METHODS

In this study, we observed the precise involvement of depsipeptide role on cancer metastasis. A549 cells were treated with depsipeptide at various concentrations (50 and 100nm), for 24h period and then subjected to mRNA levels with RT-PCR and protein levels with Western blot analysis to investigate the impact of depsipeptide on MMP-2 and MMP-9 expressions and further confirmed by using immunocytochemistry.

RESULTS

The results showed that depsipeptide treatment decreased the expressions of MMP-2 and MMP-9 in dose-dependent manner. The level of mRNA and proteins expressions were significantly decreased in depsipeptide treated A549 cells in a dose-dependent manner and the level of pro-MMP-9 was found to be high in the 100nm depsipeptide-treated cell lysate of A549 cells, suggesting inhibitory role of depsipeptide on pro-MMP-9 activation. Further immunocytochemistry studies showed the weak expression of MMP-2 and MMP-9 in depsipeptide treated cells.

CONCLUSION

We speculate that inhibition of metastasis-specific MMPs in cancer cells may be one of the targets for anticancer function of depsipeptide, and thus provides the molecular basis for the development of depsipeptide as a novel chemopreventive agent for metastatic lung cancer.

The p75(NTR) metastasis suppressor inhibits urokinase plasminogen activator, matrix metalloproteinase-2 and matrix metalloproteinase-9 in PC-3 prostate cancer cells

The p75 neurotrophin receptor (p75(NTR)) has been characterized as a metastasis and tumor suppressor in prostate cancer. In order to investigate the mechanism(s) by which the p75(NTR) functions as a metastasis suppressor in prostate cancer cells, we characterized the ectopic expression of p75(NTR) on the urokinase plasminogen activator (uPA) and the type IV collagen matrix metalloproteinases (MMP-2 and MMP-9) in PC-3 human prostate cancer cells. Rank-order expression of p75(NTR) greatly reduced protein levels and enzymatic activities of uPA, MMP-2, and MMP-9 as shown by immunoblot and zymography analyses. Conversely, expression of the MMP-9 antagonist, tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) exhibited an increase in protein levels with an increase in p75(NTR) levels, whereas TIMP-2 was not detected. Transient transfection with an inducible dominant negative antagonist Deltap75(NTR) rescued uPA, MMP-2, and MMP-9 protein levels and protease activities, and conversely suppressed TIMP-1 levels. Since p75(NTR) signal transduction occurs via the NFkappaB and JNK pathways, antagonism of signaling intermediates in these pathways, using dominant negative IKKbeta or dominant negative MKK-4, respectively, was shown to further decrease expression of uPA, MMP-2, and MMP-9 protein and enzymatic activity levels, and conversely up-regulate levels of TIMP-1. These results indicate that expression of uPA, MMP-2, MMP-9, and TIMP-1 are directly regulated by expression of p75(NTR) and its downstream signal transduction cascade. These results suggest that the metastasis suppressor activity of p75(NTR) is mediated, in part, by down-regulation of specific proteases (uPA, type IV collagenases) implicated in cell migration and metastasis.

Decreased RECK expression indicating proteolytic imbalance in prostate cancer is associated with higher tumor aggressiveness and risk of prostate-specific antigen relapse after radical prostatectomy

OBJECTIVES

Decreased expression of reversion-inducing cysteine-rich protein with Kazal motifs (RECK) was recently shown in several cancer types. To evaluate its potential role for prostate carcinoma, we investigated RECK expression in prostate cancer (pCA) samples.

METHODS

RECK messenger RNA levels in 15 microdissected normal/tumor matches were determined by quantitative reverse transcriptase-polymerase chain reaction. Protein expression of RECK was evaluated by immunohistochemical staining in tissue samples of adenomectomies (n=24) and pCA samples after radical prostatectomy (n=247). RECK expression was related to preoperative prostate-specific antigen (PSA), tumor stage and grade, surgical margin status, and PSA relapse-free time after radical prostatectomy.

RESULTS

Consistent with lower RECK messenger RNA by 24%, RECK protein expression was decreased in pCA, compared with adjacent normal tissue and prostatic intraepithelial neoplasia. RECK expression in samples of benign prostatic hyperplasia from adenomectomy specimens was higher than in normal adjacent tissue of prostate carcinomas. Decreased RECK expression was associated with higher Gleason score (> or =7) and higher tumor stage. Multivariate analysis using the Cox proportional hazards model revealed that negative RECK expression was an independent prognostic factor for an increased risk of PSA relapse, especially in patients with higher tumor grades (Gleason score > or =7).

CONCLUSIONS

Decreased RECK expression correlating with the aggressiveness of pCA and the PSA relapse-free time could become an adjunct tissue biomarker to improve the follow-up and treatment decision for these pCA patients.

Expression and functional role of CCR9 in prostate cancer cell migration and invasion

PURPOSE

Metastasis is responsible for most cancer-related deaths; hence, therapies designed to minimize metastasis are greatly needed. The precise cellular and molecular mechanisms used by cancer cells for metastasis are not fully understood; however, the metastatic spread of neoplastic cells is probably related to the ability of these cells to migrate, invade, home, and survive locally. The migration of tumor cells shares many similarities with leukocyte trafficking, which is regulated by chemokine receptor-ligand interactions. The current study evaluates the molecular mechanisms of CCL25 and CCR9 in prostate cancer cell migration and invasion.

EXPERIMENTAL DESIGN

In the current study, real-time quantitative polymerase chain reaction, flow cytometry analysis, and in vitro migration as well as invasion chamber analysis (with and without antibody-mediated inhibition) were used to ascertain the biological and functional significance of CCR9 expression by normal prostatic epithelial cells (PrEC) or prostate cancer cell lines (LNCaP-10995 and PC3).

RESULTS

We report that functional CCR9 is highly expressed by LNCaP cells and modestly, yet significantly, expressed by PC3 cells when compared with PrEC cells. Neutralization of CCL25-CCR9 interactions impaired the migration and invasion potential of the LNCaP and PC3 cell lines. CCL25 differentially modulated the expression of collagenase-1 or matrix metalloproteinase (MMP)-1, collagenase-3 (MMP-13), stromalysin-2 (MMP-10), stromalysin-3 (MMP-11), and gelatinase-A (MMP-2), but not MMP-3, MMP-7, MMP-8, MMP-9, MMP-12, or MMP-14 in prostate cancer cells.

CONCLUSIONS

These studies suggest that the expression and activation of CCR9 affect cancer cell migration, invasion, and MMP expression, which together may affect prostate cancer metastasis.

Identification of degradome components associated with prostate cancer progression by expression analysis of human prostatic tissues

Extracellular proteases of the matrix metalloproteinase (MMP) and serine protease families participate in many aspects of tumour growth and metastasis. Using quantitative real-time RT–PCR analysis, we have undertaken a comprehensive survey of the expression of these enzymes and of their natural inhibitors in 44 cases of human prostate cancer and 23 benign prostate specimens. We found increased expression of MMP10, 15, 24, 25 and 26, urokinase plasminogen activator-receptor (uPAR) and plasminogen activator inhibitor-1 (PAI1), and the newly characterised serine proteases hepsin and matriptase-1 (MTSP1) in malignant tissue compared to benign prostate tissue. In contrast, there was significantly decreased expression of MMP2 and MMP23, maspin, and the protease inhibitors tissue inhibitor of metalloproteinase 3 (TIMP3), TIMP4 and RECK (reversion-inducing cysteine-rich protein with Kazal motifs) in the cancer specimens. The expression of MMP15 and MMP26 correlated positively with Gleason score, whereas TIMP3, TIMP4 and RECK expression correlated negatively with Gleason score. The cellular localisation of the expression of the deregulated genes was evaluated using primary malignant epithelial and stromal cell cultures derived from radical prostatectomy specimens. MMP10 and 25, hepsin, MTSP1 and maspin showed predominantly epithelial expression, whereas TIMP 3 and 4, RECK, MMP2 and 23, uPAR and PAI1 were produced primarily by stromal cells. These data provide the first comprehensive and quantitative analysis of the expression and localisation of MMPs and their inhibitors in human prostate cancer, leading to the identification of several genes involved in proteolysis as potential prognostic indicators, in particular hepsin, MTSP1, MMP26, PAI1, uPAR, MMP15, TIMP3, TIMP4, maspin and RECK.

Gelatinases (MMP-2 and -9) and their natural inhibitors as prognostic indicators in solid cancers

Neoplastic growth and dissemination involve increased proteolytic activity that is able to escape the regulative elements. Matrix metalloproteinases (MMPs), particularly gelatinases A and B (MMP-2 and -9), play a role in tumor invasion and angiogenesis, and they participate in cancer progression in several neoplasias. The expression of tissue inhibitors of gelatinases, TIMPs-1 and -2, has also been shown to be associated with the clinical course in some cancers. The prognostic value of these markers, however, seems to vary a great deal in different neoplastic diseases. In this review, the impact of the gelatinases and their inhibitors on the clinical course in several solid cancers is evaluated based on the growing data from recent clinical studies. The clinical data most often explore the overexpression of mRNA or immunoreactive protein in tumor tissue, or measure the concentration of the circulating proteinase or its inhibitor in pretreatment or follow-up serum samples. The growing amount of recent clinical data suggests that the impact of gelatinases on treatment decisions should be tested in clinical trials.

Limited processing of pro-matrix metalloprotease-2 (gelatinase A) overexpressed by transfection in PC-3 human prostate tumor cells: association with restricted cell surface localization of membrane-type matrix metalloproteinase-1

The expression and activation of matrix metalloproteinases (MMPs) by tumor cells is correlated with progression to invasive and metastatic status. The purpose of this study was to examine the role of increased MMP-2 (gelatinase A) expression in prostate cancer progression utilizing human prostate PC-3 cancer cells that overexpress MMP-2 using gene transfection. PC-3 cells were transfected with pCR-3 vector only and pCR-3 MMP-2 plasmids employing the LipofectAMINE method, and stable transfectants were selected with G418. The expression of MMP-2, tissue inhibitor of metalloproteinase-2 (TIMP-2), and membrane-type MMP 1 (MT1-MMP) in PC-3 parental and transfected cells under serum-free conditions was determined by zymography, immunoblotting, immunofluorescent microscopy, Northern blotting, and/or reverse transcriptase-polymerase chain reaction (RT-PCR). MMP-2 transfected cells produced primarily the proenzyme form of MMP-2; the parental and vector control transfected PC-3 cells did not express any MMP-2 that was detectable by the methods we employed. Treatment of PC-3 MMP-2 transfected cells with Concanavalin A (Con A), in contrast to HT-1080 cells, processed only a small amount of the secreted 72-kd proenzyme to a 62-kd intermediate and a cell-associated 59-kd active form. The low level of secreted pro-MMP-2 processing induced by Con A was inhibited by serine protease inhibitors and was unaffected by cyclic adenosine monophosphate (cAMP). Immunoblotting showed that these cells produced abundant TIMP-2 and lower amounts of MT1-MMP in comparison with Con A-responding HT-1080 cells. HT-1080 cells respond to Con A by translocating MT1-MMP from intracellular localization sites to the plasma membrane, an effect not observed in PC-3 cells. The molecular basis for the low level of processing of pro-MMP-2 by PC-3 cells may be due to an overabundance of TIMP-2 and/or a low level of cell surface active MT1-MMP.

Upregulation of the tissue inhibitor of metalloproteinase-1 protein is associated with progression of human non-small-cell lung cancer

PURPOSE

Tissue inhibitors of metalloproteinases (TIMPs) are naturally occurring inhibitors of matrix metalloproteinases (MMPs). It has been shown that TIMP-1 may be a multifunctional protein. Little is known about the role of TIMP-1 in progression and metastasis of human lung cancer (tumor inhibiting or tumor promoting), although studies using a variety of techniques have analyzed the expression of TIMP-1 mRNA and/or protein in human cancers.

PATIENTS AND METHODS

We examined the expression of TIMP-1 protein by immunohistochemistry in patients (n = 160) with primary respectable (stage I to IIIA) non-small-cell lung cancer (NSCLC).

RESULTS

Twenty-seven percent of the tumors (43 of 160) demonstrated elevated expression of this protein. We demonstrate that overexpression of TIMP-1 protein is associated with an adverse outcome. In addition, disease stage, patient's age, and performance status were all significantly related to survival. In multivariate analyses, patients with high TIMP-1 expression had a 90% increased risk of death when compared with those with low expression (relative risk, 1.92; 95% CI, 1.19 to 3.09; P =.008). TIMP-1 expression did not correlate with expression of MMP-2 and MMP-9.

CONCLUSION

These results suggest that TIMP-1, independent of its inhibiting activity of MMPs, may have other function(s) critical for NSCLCs. The significance of our results is two-fold. The adverse outcome in patients with overexpression of TIMP-1 indicates its potential prognostic value in NSCLC. Thus, TIMP-1 overexpression may serve to help identify patients with particularly aggressive disease for adjuvant treatments. In addition, the TIMP-1 molecule may represent a novel therapeutic target for treatment of some NSCLCs.

High mobility group protein HMGI(Y) enhances tumor cell growth, invasion, and matrix metalloproteinase-2 expression in prostate cancer cells

BACKGROUND

The high mobility group protein HMGI(Y) has oncogenic properties and correlates with an aggressive phenotype in prostate cancer. The molecular mechanisms involved in transformation associated with HMGI(Y) overexpression remain unknown.

METHODS

The HMG-I isoform was transfected and overexpressed in nonmetastatic Dunning prostate cancer cells (G cells) without detectable HMGI(Y). The assays of cell proliferation, tumor formation, in vitro invasion, and cDNA microarray were performed to assess the effect of HMGI(Y) overexpression in the transfected G cells.

RESULTS

Overexpression of HMG-I in G cells significantly increases cell proliferation and tumor growth and also modestly enhances in vitro invasion compared to mock transfectant. cDNA microarray revealed that expression of the matrix metalloproteinase-2 (MMP-2) proform was increased eightfold in G cells overexpressing HMG-I.

CONCLUSIONS

Overexpression of HMG-I in prostate cancer cells enhances cell growth, invasion, and expression of the proform of MMP-2, which may initiate early steps involved in the metastatic cascade.

Up-regulation of cathepsin X in prostate cancer and prostatic intraepithelial neoplasia

BACKGROUND

Evidence is accumulating that several proteases are involved in prostate cancer progression. A locus which is often amplified in prostate cancer is the chromosomal region 20q13. Interestingly, one of the genes encoding the cysteine protease cathepsin X maps to this region. The aim of this study was to assess the expression pattern of cathepsin X in malignant and non-malignant prostatic tissue samples.

METHODS

Matched malignant and non-malignant tissue specimens were obtained from 56 men after radical prostatectomy. Cathepsin X was quantified at both protein and mRNA levels using several detection methods: Western blotting, immunohistochemistry, quantitative RT-PCR, and in situ hybridization. Furthermore, genomic DNA was analyzed by PCR for possible gene amplification.

RESULTS

Immunohistochemical analysis of formalin-fixed, paraffin-embedded sections of radical prostatectomy specimens was performed utilizing a polyclonal antibody against human procathepsin X and revealed staining of acinar basal cells in normal prostate glands. Prostatic intraepithelial neoplasias (PINs) and prostate carcinomas stained highly positive for cathepsin X, showing a significant difference to the staining of normal prostate glands. In contrast, relatively weak and heterogeneous staining was observed for cathepsins F, B, and L. Up-regulation of cathepsin X at the protein level was confirmed by Western blotting. No statistically significant difference was observed at the mRNA level. PCR of genomic DNA revealed that cathepsin X up-regulation most likely occurs in the absence of genomic amplification.

CONCLUSIONS

The high expression levels of cathepsin X both in PIN and invasive adenocarcinomas of the prostate suggest that cathepsin X may play a role in the early tumorigenesis of prostate cancer. Further studies are needed to define the utility of this cysteine protease as a diagnostic marker for the early detection of prostate cancer.

The metalloproteinase inhibitor TIMP-2 is down-regulated by androgens in LNCaP prostate carcinoma cells

Tissue inhibitors of metalloproteinases (TIMPs) have been shown to perform several biological functions in tumor promotion, principally by their action of inhibiting matrix metalloproteinases (MMPs) at different steps of the metastatic process. In particular, TIMP-2 is involved in a functional complex with the membrane-type 1 (MT1) MMP to convert the secreted MMP-2 progelatinase into the fully active proteolytic enzyme. We used the human, androgen-sensitive prostate carcinoma cell line LNCaP in coculture with the human osteosarcoma cell line OHS to experimentally address the possibility of androgen-dependent regulatory effects on the functional MT1-MMP/TIMP-2/MMP-2 complex upon interaction between prostate carcinoma and osteoblastic cells in metastasis of prostate cancer to bone. In the LNCaP cells a gradual, time-dependent decline in TIMP-2 mRNA expression was observed in the presence of the synthetic androgen analogue R1881 (100 nM), reaching approximately 25% of the control level after 48 h of incubation. Consistent with this, the accumulation of secreted TIMP-2 in media from R1881-treated cells was significantly inhibited already after 3 h. Neither MMP-2 gelatinolytic activity nor expression of MT1-MMP was detected in LNCaP cells. In contrast, the OHS cells showed membrane-associated MT1-MMP expression as well as MMP-2 secretion. However, R1881 treatment of the LNCaP/OHS coculture model did not seem to change the overall proteolytic activity of the MT1 -MMP/TIMP-2/MMP-2 complex. Hormonal control of TIMP-2 expression in prostate carcinoma cells has not been previously reported, but whether such regulation has any functional role in the development of osteoblastic metastases in prostate cancer is still unclear.

Characterization of expression of matrix metalloproteinases and tissue inhibitors of metalloproteinases in prostate cancer cell lines

Stromal expression of some matrix metalloproteinases (MMPs) has been associated with increasing tumour burden in prostate cancer. We investigated the expression of mRNA (by RT-PCR) and protein (by zymography and western blotting) of MMPs and endogenous inhibitors (tissue inhibitors of metalloproteinases, TIMPs) in two parent epithelial prostate cancer cell lines and sublines of increasing invasive/metastatic potential. Expression of membrane type MMPs, MT1-MMP and MT3-MMP mRNA was higher in PC3-derived than in LNCaP-derived lines, whereas MT2-MMP mRNA expression was higher in the LNCaPderived than in PC3-derived cell lines. Active MT1, MT2 and MT3-MMP protein levels were similar in all lines, but processed MT-MMPs, indicative of latent MMP activation, were increased in more aggressive sublines. Expression of MMP-1, MMP-13 and TIMP-1 was higher in the more aggressive sublines and may be implicated in invasive/metastatic ability. Regulation of MMP-1 and MMP-13 expression may offer important therapeutic options for treating patients with prostate cancer.

Pathogenesis and significance of collagenous micronodules of the prostate

Collagenous micronodules, also known as mucinous fibroplasia, are microscopic structures characterized by the presence of small eosinophilic nodules in areas immediately adjacent to prostatic glandular epithelium. The pathogenesis of collagenous micronodules is unknown, although their relation with mucin has been suggested. The objective of our study was to analyze the structural characteristics of collagenous micronodules by using histochemistry, immunohistochemistry, and electron microscopy to elucidate the pathogenesis of this lesion. We analyzed 15 cases of prostate adenocarcinoma (12 prostatectomy specimens and 3 biopsy specimens) with collagenous micronodules. The collagenous micronodules were closely associated with well-formed malignant glands, where tumor cells exhibited basophilic to amphophilic cytoplasm. Occasionally, intraluminal collagen fragments were observed within malignant but not benign glands. Collagenous micronodules were not associated with mucin, confirmed by negative stainings of mucicarmin or alcian blue in all the collagenous micronodules analyzed in this study. Therefore, the term "mucinous fibroplasia" may not be accurate. Collagenous micronodules stained weakly positive for periodic acid-Schiff. Trichrome stain highlighted the presence of collagenous micronodules as distinct blue structures. Collagen IV and laminin immunostaining performed in 12 cases outlined the micronodules with minimal staining in the center. These findings indicated that collagenous micronodules consisted of predominantly collagen fragments admixed with basement membrane material. Ultrastructurally, they were composed of fragmented banded collagen fibrils surrounded by the basement membrane material. Collagenous micronodules are formed by subepithelial accumulations of fragmented collagen fibers, possibly related to the digestion by collagenase produced by prostatic adenocarcinoma cells.

Prognostic significance of matrix metalloproteinase 2 and tissue inhibitor of metalloproteinase 2 expression in prostate cancer

Matrix metalloproteinases (MMPs) are proteolytic enzymes capable of degrading the structural support network for normal and malignant cells, promoting neoplastic cell invasion and metastasis. Tissue inhibitors of metalloproteinases (TIMPs) maintain connective tissue integrity by modulating MMP activity. Formalin-fixed paraffin-embedded tissue sections from 138 prostatic adenocarcinomas (PACs) were immunostained by a combined automated/manual method using monoclonal antibodies against MMP2 and TIMP2. Immunoreactivity was semiquantitatively scored based on stain intensity and distribution, and results were correlated with Gleason grade, pathologic stage, ploidy status, and disease recurrence. One hundred five of 138 (76%) and 113/138 (82%) PACs expressed MMP2 and TIMP2, respectively. Co-expression was observed in 94/138 (68%) of PACs (P =.01), correlated with advanced tumor stage (P =.05), and tended to be associated with disease recurrent cases (P =.07). TIMP2 expression individually correlated with advanced tumor stage (P =.04) and reached near significance with disease recurrence (P =.06). MMP2 expression was also more frequent in recurrent PACs, although this value did not reach statistical significance (P =.07). However, on multivariate analysis, only pathologic stage (P =.009) and ploidy status (P =.03) independently predicted disease recurrence. In conclusion, MMP2 and TIMP2 are co-expressed in a majority of PACs and correlate with prognostic variables. Interestingly, contrary to the previously documented anti-tumor effects of TIMPs, TIMP2 expression appears to have a tumor-promoting role in PACs and warrants further investigation.

Plasma matrix metalloproteinase 9 as biomarker of prostate cancer progression in Dunning (Copenhagen) rats

BACKGROUND

Matrix metalloproteinases (MMPs) play an important role in invasion and metastatic spread of cancer cells. The objective of this study was to assess MMPs in plasma of Dunning tumor rats as indicators of the progression of prostate cancer and follow-up parameters after treatment.

METHODS

Prostate cancer was induced in male Copenhagen rats by either subcutaneous or orthotopic implantation of R3327-MatLyLu cells. During the development of the tumor, plasma MMP-2, and MMP-9 were measured by gelatin-substrate zymography and Western blot technique with densitometry in untreated animals, rats treated with laser-induced hyperthermia, or with the new synthetic MMP inhibitor RO 28-2653.

RESULTS

Normal prostatic tissue of the Copenhagen rats predominantly expressed proMMP-2 but not proMMP-9 whereas MMP-9 was only found in cancerous tissue. Elevated plasma MMP-9 values were demonstrated in rats with subcutaneous or orthotopic tumors. Animals with tumors and treated with the MMP inhibitor RO 28-2653 had both a lower tumor volume and a lower plasma MMP-9 concentration compared with controls.

CONCLUSIONS

The determination of plasma MMP-9 in Dunning tumor rats is a useful tool to monitor the progression of prostate cancer and to assess the efficacy of drugs like MMP inhibitors or other treatment protocols.

Different mRNA and protein expression of matrix metalloproteinases 2 and 9 and tissue inhibitor of metalloproteinases 1 in benign and malignant prostate tissue

OBJECTIVE

The aim of this study was to assess the behavior of the matrix metalloproteinases (MMPs) 2 and 9 and the tissue inhibitor of metalloproteinases 1 (TIMP-1) in human prostate cancer.

METHODS

mRNA and protein expression patterns of MMP-2, MMP-9, and TIMP-1 were studied in cancerous and noncancerous parts of 17 prostates removed by radical prostatectomy. Competitive RT-PCR, gelatin-substrate zymography, and ELISA techniques were used for quantification.

RESULTS

On the mRNA level, MMP-2 expression was decreased and MMP-9, TIMP-1, the ratios of MMP-2 and MMP-9 to TIMP-1 were unchanged in cancerous tissue compared to the normal counterparts. On the protein level, expression of MMP-9 was significantly higher and TIMP-1 expression was significantly lower, MMP-2 was unchanged and the ratios of MMP-2 and MMP-9 to TIMP-1 were increased in tumor tissue.

CONCLUSIONS

The higher concentration of MMP-9 as well as the increased ratios of MMP-2 and MMP-9 to TIMP-1 in malignant tissue prove the proteolytic dysbalance in prostate cancer, which does not seem to be associated with the stage and grade of the tumor. Comparison of mRNA and protein expression of MMP-2, MMP-9 and TIMP-1, respectively, did not show any significant relationships illustrating the necessity to study these components at both molecular levels.

Expression of matrix metalloproteinase-2 and -9 and their inhibitors, tissue inhibitor of metalloproteinase-1 and -2, in primary cultures of human prostatic stromal and epithelial cells

The production of matrix metalloproteinases (MMPs) by prostatic epithelial and/or neighboring stromal cells is considered to be a property that gives cells the capability to penetrate extracellular matrix barriers in normal or neoplastic growth. In order to examine the role of MMPs in the prostate, we evaluated the expression of MMP-2 and -9 and the tissue inhibitors of matrix metalloproteinases (TIMP)-1 and -2 in primary cultures of prostatic stromal and epithelial cells. These cells were isolated from normal tissues of the different zones of the prostate, from benign prostatic hyperplasia (BPH) and from cancer. Stromal cells, regardless of tissue of origin, secreted the 72-kDa proenzyme form of MMP-2, whereas conditioned media (CM) from epithelial cells demonstrated little/no pro-MMP-2 as examined by zymography. Either type of cell did not secrete MMP-9. RT-PCR evaluation showed stromal cells expressed transcripts for MMP-2, but not for MMP-9. Transcripts for MMP-9 were detected in epithelial cells, although no MMP-9 activity was detected in their CM. Treatment of stromal cells with 1 or 10 ng/ml of transforming growth factor-beta (TGF-beta) moderately increased secretion of pro-MMP-2 protein with little change in MMP-2 RNA. However, treatment of epithelial cells with TGF-beta induced expression and secretion of both MMP-2 and-9. The effect of TGF-beta on expression of MMPs by epithelial cells was not duplicated or affected by treatment with insulin-like growth factor (IGF)-1, epidermal growth factor (EGF), platelet-derived growth factor (PDGF), or basic fibroblast growth factor (bFGF). Stromal cells expressed transcripts of both TIMP-1 and -2. Epithelial cells expressed TIMP-1, but little TIMP-2. TGF-beta did not regulate the expression of TIMP-1 or -2 in either stromal or epithelial cells. Our results suggest that the elevated levels of MMP-2 and -9 observed in prostate development and cancer may be due to the elevated TGF-beta associated with these tissues.

Complex roles of tissue inhibitors of metalloproteinases in cancer

Matrix metalloproteinases (MMPs) is tightly associated with extracellular matrix (ECM) turnover, which plays a very active role in tumor invasion and metastasis. Tissue inhibitors of metalloproteinases (TIMPs) plays a critical role in the homeostasis of ECM by regulating the activity of MMPs. TIMPs are well-known for their ability to inhibit MMP activity thereby inhibiting tumor growth and metastasis. However, many evidences suggest that TIMPs are multifunctional proteins, which regulate cell proliferation, apoptosis, proMMP-2 activation, and angiogenesis. These effects may be through MMP-dependent or MMP-independent pathways. Recent data indicate that TIMPs have many paradoxical roles in tumorigenesis. In particular, both inhibitory effect and stimulatory effect on tumorigenesis have been demonstrated in many animal models in which TIMPs were overexpressed in cancer cells or in mice. Elevated TIMP levels are reported in association with cancer progression and identified as poor prognostic indicators in several human tumor types. Herein, we review the complex roles of TIMPs in cancer growth and metastasis.

The new synthetic matrix metalloproteinase inhibitor (Roche 28-2653) reduces tumor growth and prolongs survival in a prostate cancer standard rat model

The therapeutic efficacy of synthetic inhibitors of matrix-metalloproteinases (MMPs) in various cancers has been demonstrated. A novel inhibitor, Ro 28-2653, with high selectivity for MMP2, MMP9 and membrane type 1-MMP was evaluated in an orthotopic prostate cancer rat model. Efficacy was determined by recording tumor growth and survival endpoints. Prostate cancer was induced by inoculating R3327 Dunning tumor cells (MatLyLu) into the ventral lobe of the prostates of 148 Copenhagen rats. Daily oral treatment with Ro 28-2653 (10-300 mg/kg per day) was started on day 1 or on day 6 after tumor cell injection. Animals were sacrificed on day 20 for determination of tumor weights. For survival studies, rats received daily oral Ro 28-2653 (100 mg/kg per day) or vehicle for up to 30 days. Tumor induction was successful in 100% of the animals. Ro 28-2653 reproducibly reduced the tumor weights by up to 90% in a dose-dependent manner. In addition, an inhibitory effect in rats with established tumors (treatment start at day 6) was shown. A significantly prolonged survival of Ro 28-2653-treated rats was also demonstrated. Selective inhibition of MMP activity is a novel therapeutic approach, which bears promise for studies in patients with prostate cancer.

Presence of active gelatinases in endometrial carcinoma and correlation of matrix metalloproteinase expression with increasing tumor grade and invasion

BACKGROUND

The actions of the extracellular-matrix degrading enzymes, matrix metalloproteinases (MMPs), are implicated in tumorigenesis. The cellular localization of MMP-2, MMP-9, membrane type 1 (MT1)-MMP, tissue inhibitors of metalloproteinases (TIMPs) 1-3, and the presence of active gelatinases were investigated in endometrial carcinoma.

METHODS

Endometrial carcinomas were grouped according to histologic grade (Grades 1-3), depth of myometrial invasion (0, < 50%, > 50%) and the presence of vascular/lymphatic invasion. Twenty-nine endometrial carcinoma biopsies were investigated immunohistochemically to determine the tissue localization of MMP-2 (gelatinase A), MMP-9 (gelatinase B), MT1-MMP, and TIMPs 1-3. In situ hybridization was performed to localize MMP-2 and MMP-9 mRNA. The presence of active gelatinases was assessed using in situ zymography.

RESULTS

Epithelial tumor cells were the main site of MMP-2, MMP-9, and MT1-MMP protein. Variable stromal cell localization was also observed, particularly in areas adjacent to tumor nests. Semiquantitative analysis revealed increases in MMP-9 and MMP-2 but not MT1-MMP staining scores in tumor epithelial cells in the transition from histologic Grade 1 to Grades 2 and 3. Matrix metalloproteinase-9 and MT1-MMP staining scores in tumor cells were significantly associated with the presence of myometrial invasion and vascular/lymphatic invasion, while MMP-2 did not correlate with these factors. In addition, MT1-MMP was co-localized with MMP-2, supporting its role in the activation of proMMP-2. Tumor cells from all histologic grades stained intensely for TIMP-2 and TIMP-3 proteins, while variable stromal staining was observed. In Grade 1 carcinomas TIMP-1 was predominantly immunolocalized to the stromal compartment with variable tumor cell localization being observed in Grades 2 and 3 carcinomas. Matrix metalloproteinase-9 and MMP-2 mRNAs were predominantly observed in tumor epithelial cells as well as in the stroma to varying degrees. In situ zymography revealed active forms of gelatinases at the cellular surface and in association with tumor epithelial cells within endometrial carcinoma tissues.

CONCLUSIONS

These data suggest that increasing expression of MMPs and endometrial carcinoma progression are closely related. Active gelatinases are present in endometrial carcinoma, resulting in alterations to the microenvironment that promote tumor invasion and metastasis.

Differential expression of matrix metalloproteinases and their tissue inhibitors in human primary cultured prostatic cells and malignant prostate cell lines

BACKGROUND

The aim was to investigate the expression of matrix metalloproteinases (MMPs), membrane type MMPs (MT-MMPs), and their inhibitors (TIMPs) in human primary cultured prostatic cells and malignant prostate cell lines.

METHODS

Reverse transcription-polymerase chain reaction-based measurements of the mRNA levels of MMP-2, MMP-7, MT1-MMP, MT3-MMP, TIMP-1, and TIMP-2 in relation to the house-keeping gene glyceraldehyde phosphate dehydrogenase were performed in cancerous and non-cancerous prostatic tissue samples, in primary cell cultures of epithelial cells, in both fibroblasts, and smooth-muscle cells as stromal cells, and in the human malignant prostatic cell lines DU-145, LNCaP, and PC-3.

RESULTS

MMP-2 was mainly expressed in the stromal cells and MMP-7 showed their highest values in the epithelial cells. MT1-MMP, MT3-MMP, TIMP-1, and TIMP-2 were found both in the stromal and in the epithelial cells, but there were some differences between the expressions in fibroblasts and smooth-muscle cells. Different expressions were also observed between the cells deriving from the primary cell cultures, the benign cell line BPH-1, and the malignant cell lines LNCaP, D-145, and PC-3.

CONCLUSIONS

These exemplary results concerning different expressions of MMPs and TIMPs in cells from prostatic tissue suggest that a better insight into changes observed in prostatic tissue needs studies on cells cultured from the tissue.

Altered expression of extracellular matrix and proteinases in Noble rat prostate gland after long-term treatment with sex steroids

BACKGROUND

Interactions between the epithelial cells and stromal tissues, which include the epithelial basement membrane, extracellular matrix, inducible factors, and various cell types, are believed to play a significant role in prostate gland carcinogenesis. Remodeling of extracellular matrix and degradation of basement membrane are the prerequisites for tumor cell invasion, and these changes are correlated with the expression of various proteinases.

METHODS

The present study examined the alterations of epithelial basement membrane, extracellular matrix, and proteinase activities in the Noble rat prostate gland after long-term treatments with androgen and estrogen (T+DES or T+E(2) for 4-12 months) by histochemistry, immunohistochemistry, electron microscopy, and gelatin-gel zymography.

RESULTS

After hormonal treatments, defects of epithelial basement membranes, such as focal disruption, diffuse staining and multilayering, were observed by histochemistry and immunohistochemistry in the dysplastic and neoplastic lesions induced in the lateral (LP) and ventral prostates (VP) but not in dorsal prostate (DP). An increase in the amount of extracellular matrix components, including hyaluronan (HA), chondroitin sulfate proteoglycan (CSPG) and tenascin, in the stroma of hormone-treated LP and VP was revealed by histochemistry and immunohistochemistry. Positive immunolabeling of matrix metalloproteinases 2 (MMP-2) and 9 (MMP-9) was detected in the fibromuscular layer surrounding the adenoma and adenocarcinoma induced in LP and VP after treatments with steroids for over 9-12 months. Zymography also detected an increase in activities of proteinases of apparent MW 120, 90, 86 and 68 kDa in the hormone-treated LP and VP, and these proteinases were characterized as metalloproteinases. In addition, two serine proteinases of MW 100 and 30 kDa were identified as being overexpressed in the hormone-treated LP and VP. Compared to LP and VP, there was no significant change in the proteinase activities in the hormone-treated DP.

CONCLUSIONS

The present study demonstrated that the epithelial basement membrane and stromal extracellular matrix were altered in dysplastic and neoplastic Noble rat prostates. Since HA and CSPG (or their complexes) are highly anionic molecules, their increased accumulation in the altered prostatic stroma would tend to hydrate this tissue. This would create an environment more favorable for tumor growth and invasion. These morphological changes were also correlated with the concurrent increase in gelatinolytic proteinase activities induced in these prostates. The results suggest that the remodeling of the stromal tissue might play a role in the early stage of prostate carcinogenesis as shown in the Noble rat model.

Ratio of cathepsin B to stefin A identifies heterogeneity within Gleason histologic scores for human prostate cancer

BACKGROUND

Cathepsin B (CB), a lysosomal cysteine protease, is involved in degradation of extracellular matrix proteins and progression of tumor cells from one biological compartment to another in many solid organ cancers, including prostate cancer. Our objective was to identify patterns of distribution of CB and its endogenous cellular inhibitor stefin A in cryostat sections of frozen BPH and prostate cancer tissue samples and to define these patterns in relation to Gleason histologic scores, clinical stages, and serum total PSA levels.

METHODS

We localized CB and stefin A in the same sections using polyclonal and monoclonal antibody immunoglobulin G (IgGs) against CB and stefin A using immunofluorescence and confocal microscopic techniques. Only cryostat sections of frozen prostates were used in localizations of CB and stefin A.

RESULTS

Benign prostatic hyperplasia (BPH) showed similar localization patterns for CB and stefin A and a ratio of 1 was indicated by CB = stefin A. Confocal studies indicated that most CB and stefin A sites in BPH glandular cells overlapped as shown by the yellow fluorescence of their co-localization. We found considerable variability in individual localization of CB and stefin A within and between Gleason histologic scores for prostate cancers. This variability was also found in Gleason score 6 tumors that are otherwise considered similar histologically and morphologically. Negative control sections did not show localization of CB by FITC, stefin A by Cy3 or yellow fluorescence for co-localization. Our analysis of the ratio of CB to stefin A showed three patterns, namely CB = stefin A, CB > stefin A, and CB < stefin A, within each Gleason score evaluated by us. Confocal microscopy showed more sites of yellow fluorescence when the ratio was CB = stefin A than those found in CB > stefin A or CB < stefin A. Statistical analyses showed prostate cancer cases with ratios of CB > stefin A (P < 0.05) and CB < stefin A (P < 0.05) significantly different from normal prostate and BPH which had ratios of CB = stefin A. Regression analysis did not show any specific relationship between the ratio of CB to stefin A and Gleason scores, clinical stages, and serum total prostate specific antigen (PSA) levels in prostate cancers. Analysis of our data indicates that the homeostatic balance between the enzyme and inhibitor was altered even in Gleason histologic score 6 tumors that are usually considered histologically similar by glandular differentiation.

CONCLUSIONS

We have shown that prostate cancer is a heterogeneous tumor within each Gleason histological score regardless of the progression indicated by lower to higher Gleason score tumors. The ratio of CB > stefin A would indicate a preponderance of enzyme that would favor degradation of extracellular matrix proteins and progression of tumor cells in biological compartments. These tumors are expected to be aggressive prostate cancers. In contrast, prostate tumors showing ratios of CB < stefin A and CB = stefin A are expected to be less aggressive prostate cancers. This is the first report to define heterogeneity within any Gleason score for prostate cancers by the ratios of CB to stefin A.

Differential regulation of matrix metalloproteinase-9, tissue inhibitor of metalloproteinase-1 (TIMP-1) and TIMP-2 expression in co-cultures of prostate cancer and stromal cells

Tumor-stromal interactions have been suggested to be a critical factor in both tumor invasion and tumor metastasis. Here, we examined the role of tumor-stromal interactions using co-cultures of prostate cancer (PC) cells derived from primary and metastatic tumors with primary or immortalized stromal (fibroblast and smooth muscle) cells and their effect on matrix metalloproteinase (MMP) and tissue inhibitor of metalloproteinase (TIMP) expression. Co-cultures of PC and stromal cells showed enhanced levels of pro-MMP-9 and reduced levels of TIMP-1 and TIMP-2. Whereas enhanced expression of pro-MMP-9 occurred in PC cells, the TIMPs were down-regulated in stromal cells. Induction of pro-MMP-9 and reduction of TIMP expression did not require cell-cell contact and were mediated by a soluble factor(s) present in the conditioned medium of the effector cell. Collagen I is a potent inducer of pro-MMP-9 in PC cells. Consistently, preliminary characterization of the soluble factor in the fibroblast conditioned medium revealed m.w. of approximately 100 to 250 kDa, and its effect on pro-MMP-9 expression was partly inhibited by an anti-alpha2 integrin antibody, a major collagen I receptor. Expression of pro-MMP-9 protein and mRNA was also induced in metastatic PC-3 cells grown in human fetal bone implants in SCID mice. Together, these findings demonstrate the importance of tumor-stromal interactions in the regulation of MMP and TIMP expression and their potential role in PC progression.

Prognostic and predictive factors in prostate cancer

Prostate cancer is a major public health problem in the Western world, and the second most common male malignancies in the European Union. Detection of the disease is possible at an early stage, using serum prostate specific antigen measurement and prostatic biopsies. To date, however, screening for prostate cancer has not been shown to be of benefit to patients in improving outcome. This is compounded by uncertainties surrounding treatment efficacy, as more men appear to die with prostate cancer than from it. Studies addressing these issues are underway in Europe and the U.S.A. Clinicians are currently unable to advise their patients with any degree of certainty as to the appropriateness of treatment for prostate cancer, because of their inability to differentiate tumours that will progress from those that will remain quiescent. This article reviews the various clinical, pathological and experimental markers available, and their value in providing prognostic information, which may assist clinicians and patients in making management decisions. Further research is still required to understand the biological behaviour of prostate cancer and to assess the value of screening and treatment efficacy in order to advise patients, clinicians and health care systems accordingly.

Matrix metalloproteinases (MMPs) in fresh human prostate tumour tissue and organ-cultured prostate tissue: levels of collagenolytic and gelatinolytic MMPs are low, variable and different in fresh tissue versus organ-cultured tissue

Prostate tissue was obtained from 22 radical prostatectomies (performed for clinical management of prostate carcinoma) immediately after surgery. A small piece of tissue was fixed immediately in formalin and used for routine histology while a second piece was frozen in OCT and used for immuno-histochemistry. Another small piece was used for isolation of epithelial and stromal cells. The remainder of the tissue was cut into 2 x 2 mm pieces and incubated in organ culture for 8 days. In organ culture, non-malignant, basal epithelial cells underwent a proliferative response. This was accompanied by de-differentiation of glandular structures and by migration of epithelial cells across the surface of the tissue. Erosion of the basement membrane could also be seen in places, but was not widespread. Invasion of epithelial cells into the adjacent stroma was not evident. Production of matrix metalloproteinases (MMPs) with gelatinolytic activity or collagenolytic activity was assessed in organ culture and compared to expression patterns in fresh tissue. MMP-1 (interstitial collagenase) and MMP-9 (92-kDa gelatinase B) were undetectable or low in fresh tissue specimens. Both enzymes were detected in organ culture and both increased over time. Even after 6 days, however, there was only a low level of gelatin-hydrolytic activity and no measurable collagen-hydrolytic activity. In past studies we used organ cultures of normal skin and malignant skin tumours (basal cell carcinomas) to help elucidate the role of collagenolytic and gelatinolytic MMPs in epithelial cell invasion (Varani et al, 2000). Compared to MMP levels observed in skin, levels of these enzymes in prostate are low. The low level of collagenolytic and gelatinolytic MMPs in fresh prostate tissue and in organ-cultured prostate tissue may help explain why there is little tissue destruction in many primary prostate tumours and why the majority of such tumours remain confined to the prostate for extended periods.