The expression of tumor-derived and stromal-derived matrix metalloproteinase 2 predicted prognosis of ovarian cancer

Exploring natural anthraquinones as potential MMP2 inhibitors: A computational study

OBJECTIVE

Matrix metalloproteinase-2 (MMP2) plays a significant role in cleaving extracellular matrix components, leading to many cancer cells' progression and invasion behavior. Therefore, MMP2 inhibition may hold promise for cancer treatment. Anthraquinones have shown antineoplastic effects, some of which have been used in clinical practice as anticancer drugs. This study used a computational drug discovery approach to assess the possible inhibitory effects of selected anthraquinones on MMP2. The results were then compared with that of Captopril, which was considered a standard drug.

METHODS

This study used the AutoDock 4.0 tool to evaluate the binding affinity of 21 anthraquinones to the MMP2 catalytic domain. The most favorable scores based on the Gibbs free binding energy scores were given to the highest-ranked ligands. The Discovery Studio Visualizer tool illustrated interactions between MMP2 residues and top-ranked anthraquinones.

RESULTS

A total of 12 anthraquinones were identified with ΔGbinding scores less than - 10 kcal/mol. Pulmatin (Chrysophanol-8-glucoside) was the most potent MMP2 inhibitor, with a ΔGbinding score of - 12.91 kcal/mol. This anthraquinone was able to restrict MMP2 activity within a picomolar range.

CONCLUSION

MMP2 inhibition by anthraquinones, notably Pulmatin, may be a useful therapeutic approach for cancer treatment.

Molecular, cellular and systemic aspects of epithelial ovarian cancer and its tumor microenvironment

Ovarian cancer encompasses a heterogeneous group of malignancies that involve the ovaries, fallopian tubes and the peritoneal cavity. Despite major advances made within the field of cancer, the majority of patients with ovarian cancer are still being diagnosed at an advanced stage of the disease due to lack of effective screening tools. The overall survival of these patients has, therefore, not substantially improved over the past decades. Most patients undergo debulking surgery and treatment with chemotherapy, but often micrometastases remain and acquire resistance to the therapy, eventually leading to disease recurrence. Here, we summarize the current knowledge in epithelial ovarian cancer development and metastatic progression. For the most common subtypes, we focus further on the properties and functions of the immunosuppressive tumor microenvironment, including the extracellular matrix. Current and future treatment modalities are discussed and finally we provide an overview of the different experimental models used to develop novel therapies.

A Subset of Secreted Proteins in Ascites Can Predict Platinum-Free Interval in Ovarian Cancer

The time between the last cycle of chemotherapy and recurrence, the platinum-free interval (PFI), predicts overall survival in high-grade serous ovarian cancer (HGSOC). To identify secreted proteins associated with a shorter PFI, we utilized machine learning to predict the PFI from ascites composition. Ascites from stage III/IV HGSOC patients treated with neoadjuvant chemotherapy (NACT) or primary debulking surgery (PDS) were screened for secreted proteins and Lasso regression models were built to predict the PFI. Through regularization techniques, the number of analytes used in each model was reduced; to minimize overfitting, we utilized an analysis of model robustness. This resulted in models with 26 analytes and a root-mean-square error (RMSE) of 19 days for the NACT cohort and 16 analytes and an RMSE of 7 days for the PDS cohort. High concentrations of MMP-2 and EMMPRIN correlated with a shorter PFI in the NACT patients, whereas high concentrations of uPA Urokinase and MMP-3 correlated with a shorter PFI in PDS patients. Our results suggest that the analysis of ascites may be useful for outcome prediction and identified factors in the tumor microenvironment that may lead to worse outcomes. Our approach to tuning for model stability, rather than only model accuracy, may be applicable to other biomarker discovery tasks.

A thioredoxin reductase 1 inhibitor pyrano [3,2-a] phenazine inhibits A549 cells proliferation and migration through the induction of reactive oxygen species production

BACKGROUND

Thioredoxin reductase 1 (TrxR1) inhibitor, pyrano [3,2-a] phenazine, named CPUL-1, was synthesized with potential anticancer activity. The aim of the present work was to explore the potential anti-proliferative and anti-metastatic ability of CPUL-1 against A549 cancer cell lines in vitro.

METHODS AND RESULTS

First, Cell Counting Kit-8 (CCK8) assay was used to assess cell proliferation. The A549 cell migration was evaluated by wound healing assay and transwell assay. Second, the epithelial-mesenchymal transition (EMT)-related proteins in A549 cells treated with CPUL-1 were analyzed by western blot methods. Then, TrxR1 enzyme activity assay and reactive oxygen species (ROS) assay were conducted to evaluate the effect of CPUL-1 on TrxR1 inhibition and ROS levels. Finally, western blotting was used to explore the mechanism of CPUL-1. The study results revealed that the ability of cell proliferation and migration was decreased under CPUL-1 treatment. CPUL-1 could distinctly restrain the migration and invasion of A549 cells through inhibiting EMT process. The results of TrxR1 enzyme activity assay, ROS assay and western blotting showed that CPUL-1 influenced EMT via inducing ROS-mediated ERK/JNK signaling by inhibiting TrxR1 enzyme activity.

CONCLUSIONS

Together, proliferation suppression and anti-metastasis activity of CPUL-1 in A549 cells were demonstrated by all the evidence. Our findings highlight the great potential of phenazine compound CPUL-1 to suppress A549 cells proliferation and metastasis.

Expression of metalloproteinases MMP-2 and MMP-9 is associated to the presence of androgen receptor in epithelial ovarian tumors

BACKGROUND

The current study evaluated the metalloproteinases MMP-2 and MMP-9 expression in epithelial cells and the surrounding stroma in ovarian tumors and the association of MMPs with the histological subtypes, the clinical stage and the presence of steroid hormone receptors. Tumor samples were obtained from 88 patients undergoing surgical cytoreduction of primary ovarian tumors in Instituto Nacional de Cancerología, from México City. The formalin fixed and paraffin embedded samples were processed in order to demonstrate the presence of androgen receptor,estrogen receptor alpha, progesterone receptor, MMP-2,MMP-9 and collagen IV by immunohistochemistry and/or immunofluorescence.

RESULTS

MMP-2 and MMP-9 were differentially expressed in the epithelium and the stroma of ovarian tumors associated to histological subtype, clinical stage and sexual steroid hormone receptor expression. Based on Cox proportional hazard regression model we demonstrated that MMP-2 located in the epithelium and the stroma are independent prognostic biomarkers for overall survival in epithelial ovarian tumors. Kaplan Meir analysis of the combination of AR (+) with MMP-2 (+) in epithelium and AR (+) with MMP-2 (-) in stroma displayed a significant reduction of survival.

CONCLUSIONS

The presence of MMP-2 in the stroma of the tumor was a protective factor while the presence of MMP-2 in the epithelium indicated an adverse prognosis. The presence of AR associated with MMP-2 in the tumor cells was a risk factor for overall survival in epithelial ovarian cancer.

circPUM1 Promotes Tumorigenesis and Progression of Ovarian Cancer by Sponging miR-615-5p and miR-6753-5p

Circular RNAs (circRNAs) have been reported to participate in the molecular mechanism of human cancers. The PUM1 gene has been confirmed to be closely related to tumorigenesis and progression of ovarian cancer. In the present study, we explored the function and underlying molecular mechanism of circPUM1 in ovarian cancer. qRT-PCR analysis showed upregulation of circPUM1 in ovarian cancer tissues compared with normal ovaries. Gain- and loss-of-function experiments indicated that circPUM1 increased cell proliferation, migration, and invasion and inhibited cell apoptosis. Intraperitoneal injection of circPUM1-knockout tumor cells in nude mice resulted in a decrease in the metastatic ability of the tumor. Bioinformatics analysis and dual-luciferase reporter assays revealed that circPUM1 upregulated the expression of nuclear factor kappa B (NF-κB) and MMP2 by sponging miR-615-5p and miR-6753-5p. Further studies showed that exosomal circPUM1 acted on peritoneal mesothelial cells and increased tumor metastasis. In conclusion, our study indicates that circPUM1 not only promotes ovarian cancer proliferation, migration and invasion, but also acts on the peritoneum and contributes to metastasis of cancer in the form of cancer-derived exosomes.

Matrix Metalloproteinase Expressions Play Important role in Prediction of Ovarian Cancer Outcome

Ovarian cancer has a high death rate and is often not detected until late stages. While some studies found high expressions of MMPs correlated with cancer invasion, metastasis, and poor prognosis, however, several other studies indicated MMPs might inhibit cancer rather than promote cancer in certain situations. Thus, the role of different MMPs in different cancer types needs a systematic re-evaluation. In this study, we used RNA-Seq and corresponding clinical data downloaded from TCGA and analyzed the correlations between MMP expressions and the clinicopathologic characteristics and outcome in ovarian serous cystadenocarcinoma (OSC) patients. Among the MMPs investigated, MMP-3 was significantly increased in high-grade and high-stage tumors compared with low-grade and low-stage ones. Using univariate analysis and multivariate Cox model, high expressions of MMP-19 and -20 were found to associate with poor overall survival independent of clinicopathologic characteristics. Moreover, using in vitro studies, we found ovarian cancer cell lines with higher MMP-19 and -20 protein expressing levels were associated with anti-cancer drugs resistance, while knockdown of MMP-19 or -20 increased ovarian cancer cell sensitivities to several clinical using chemotherapy agents. Finally, knockdown of MMP-19 or -20 also decreased the invasion abilities of several ovarian cancer cell lines. These in vitro studies provided potential mechanisms of high MMP-19 and -20 expressions in the poor prognosis of ovarian cancer.

Matrix metalloproteinase-2: Not (just) a "hero" of the past

The 72-kDa type IV collagenase or gelatinase A is the second member of the matrix metalloproteinase family, MMP-2. Since the discovery of its first two substrates within components of the extracellular matrix, denatured interstitial type I collagen and native type IV collagen, the roles and various levels of regulation of MMP-2 have been intensively studied, mainly in vitro. Its (over)expression in most if not all tumors was considered a hallmark of cancer aggressiveness and boosted investigations aiming at its inhibition. Unfortunately, the enthusiasm subsided like a soufflé after clinical trial failures, mostly because of insufficient knowledge of in vivo MMP-2 activities and detrimental side effects of broad-spectrum MMP inhibition. Nowadays, MMP-2 remains a major topic of interest in research, the second in the MMP family after MMP-9. This review presents a broad overview of the major features of this protease. This knowledge is crucial to identify diagnostic or therapeutic strategies focusing on MMP-2. In this sense, recent publications and clinical trials underline the potential value of measuring circulating or tissular MMP-2 levels as diagnostic or prognostic tools, or as a useful secondary outcome for therapies against other primary targets. Direct MMP-2 inhibition has benefited from substantial progress in the design of more specific inhibitors but their in vivo application remains challenging but certainly worth the efforts it receives.

The prognostic values of matrix metalloproteinases in ovarian cancer

Objective

To investigate the prognostic significance of 23 matrix metalloproteinase (MMP) genes in patients diagnosed with ovarian carcinoma.

Methods

The prognostic significance of 23 MMP genes in patients diagnosed with ovarian carcinoma was investigated using the Kaplan–Meier plotter (KM plotter), which uses the gene expression data and overall survival information of patients with ovarian cancer that were downloaded from the Gene Expression Omnibus, Cancer Biomedical Informatics Grid and The Cancer Genome Atlas cancer datasets. The correlation between mRNA levels of individual MMPs (MMP2, MMP9, MMP10, MMP12, MMP13 and MMP25) and clinicopathological features (histological subtype, pathological grade and clinical stage) were investigated. The MMP protein level profiles in normal ovarian tissues and ovarian cancer tissues were examined using the Human Protein Atlas database.

Results

The results showed that high mRNA levels of MMP2 and MMP13 were associated with a worse overall survival in patients with ovarian cancer, whereas high mRNA levels of MMP9, MMP10, MMP12 and MMP25 were associated with a better overall survival. The protein levels of MMP2, MMP9, MMP10 and MMP25 in ovarian cancer tissues were elevated compared with normal ovarian tissues.

Conclusions

This study demonstrated that MMPs can be a reliable prognostic biomarker for ovarian cancer.

Cancer-Associated Fibroblasts Build and Secure the Tumor Microenvironment

Tumor cells reside in a highly complex and heterogeneous tumor microenvironment (TME), which is composed of a myriad of genetically stable non-cancer cells, including fibroblasts, immune cells, endothelial cells, and epithelial cells, and a tumor-specific extracellular matrix (ECM). Cancer-associated fibroblasts (CAFs), as an abundant and active stromal cell population in the TME, function as the signaling center and remodeling machine to aid the creation of a desmoplastic tumor niche. Although there is no denial that the TME and CAFs may have anti-tumor effects as well, a great deal of findings reported in recent years have convincingly revealed the tumor-promoting effects of CAFs and CAF-derived ECM proteins, enzymes, chemical factors and other downstream effectors. While there is growing enthusiasm for the development of CAF-targeting therapies, a better understanding of the complexities of CAF-ECM and CAF-cancer cell interactions is necessary before novel therapeutic strategies targeting the malignant tumor “soil” can be successfully implemented in the clinic.

The Air Sac Primordium of Drosophila: A Model for Invasive Development

The acquisition of invasive properties preceding tumor metastasis is critical for cancer progression. This phenomenon may result from mutagenic disruption of typical cell function, but recent evidence suggests that cancer cells frequently co-opt normal developmental programs to facilitate invasion as well. The signaling cascades that have been implicated present an obstacle to identifying effective therapeutic targets because of their complex nature and modulatory capacity through crosstalk with other pathways. Substantial efforts have been made to study invasive behavior during organogenesis in several organisms, but another model found in Drosophilamelanogaster has not been thoroughly explored. The air sac primordium (ASP) appears to be a suitable candidate for investigating the genes and morphogens required for invasion due to the distinct overlap in the events that occur during its normal growth and the development of metastatic tumor cells. Among these events are the conversion of larval cells in the trachea into a population of mitotically active cells, reduced cell–cell contact along the leading edge of the ASP, and remodeling of the extracellular matrix (ECM) that surrounds the structure. Here, we summarize the development of ASPs and invasive behavior observed therein.

Clinical significance of matrix metalloproteinase-2 in endometrial cancer: A systematic review and meta-analysis

BACKGROUND

Matrix metalloproteinase-2 (MMP-2), a member of the zinc-dependent metalloproteinase gene family, plays a vital role in cancer invasion, metastasis, and progression. This systematic review and meta-analysis aims to explore the clinical significance of MMP-2 expression in endometrial cancer.

METHODS

PubMed, Embase, Cochrane Library, and China National Knowledge Infrastructure databases were systematically searched up to September 30, 2017, supplemented by manual searches of bibliographies. Two reviewers independently identified articles, extracted data, assessed quality, and cross-checked the results. Meta-analysis was conducted to explore the difference in the positive rate of MMP-2 expression between patients with endometrial cancer and those with endometriosis or normal endometrium, and to investigate the associations of MMP-2 expression with clinicopathologic characteristics of patients with endometrial cancer. Weighted mean differences and risk ratios (RRs) with 95% confidence interval (CI) were calculated for continuous and dichotomous variables, respectively.

RESULTS

Totally 20 studies were selected for this systematic review and meta-analysis. Compared with those with endometriosis or normal endometria, the positive rate of MMP-2 expression is significantly higher in patients with endometrial cancer (RR = 2.31, 95% CI: 1.78-3.00, P < .01). MMP-2 expression was significantly associated with Federation of Gynecology and Obstetrics stage (RR = 1.19, 95% CI: 1.09-1.31, P < .01), histologic grade (RR = 1.10, 95% CI: 1.01-1.19, P = .02), lymph node metastasis (RR = 1.32, 95% CI: 1.15-1.51, P < .01), and myometrial invasion (RR = 1.25, 95% CI: 1.12-1.38, P < .01).

CONCLUSION

The results showed that MMP-2 was expressed in high percentage of endometrial cancer and its expression may be associated closely with clinical stage, and tumor invasion and metastasis, indicating that MMP-2 overexpression may serve as a predictive factor for poor prognosis of endometrial cancer.

PAX1 Methylation as a Potential Biomarker to Predict the Progression of Cervical Intraepithelial Neoplasia: A Meta-analysis of Related Studies

OBJECTIVE

The methylation of paired box gene 1 (PAX1) has a great influence on the process of cervical lesion. However, available evidence for the association between PAX1 methylation and cervical intraepithelial neoplasia (CIN) are inconsistent. Here, we systematically reviewed and analyzed PAX1 methylation in progress of CIN.

METHODS

Two investigators independently searched eligible studies of PAX1 methylation and CIN that were published in PubMed, Cochrane Library, EMBASE, and Web of Science databases until November 30, 2016. We extracted clinicopathologic features of CIN and cervical cancel relevant to PAX1 methylation. Odds ratios (ORs) with their 95% confidence intervals (CIs) were used to assess the association between PAX1 methylation and progression of patients with CIN.

RESULTS

Seven studies composed of 1055 patients with various stages of CIN and cervical cancel were eventually included. The results revealed that PAX1 methylation was associated with transition of CIN I to CIN II/III (OR, 0.09; 95% CI, 0.04-0.19) and CIN II/III to cervical cancer (OR, 0.16; 95% CI, 0.05-0.46), and similar results were produced in sensitivity analysis. Also, we found that the OR value was associated with average age and number of patients, publication year, and study location of included articles.

CONCLUSIONS

PAX1 gene methylation was associated with the transition of CIN I to CIN II/III and CIN II/III to cervical cancer, so that it could be an auxiliary biomarker to estimate the risk of CIN progress. Moreover, PAX1 may help to determine appropriate reexaminations and treatment for patients with various stages of CIN.

The Many Facets of Metzincins and Their Endogenous Inhibitors: Perspectives on Ovarian Cancer Progression

Approximately sixty per cent of ovarian cancer patients die within the first five years of diagnosis due to recurrence associated with chemoresistance. The metzincin family of metalloproteinases is enzymes involved in matrix remodeling in response to normal physiological changes and diseased states. Recently, there has been a mounting awareness of these proteinases and their endogenous inhibitors, the tissue inhibitors of metalloproteinases (TIMPs), as superb modulators of cellular communication and signaling regulating key biological processes in cancer progression. This review investigates the role of metzincins and their inhibitors in ovarian cancer. We propose that understanding the metzincins and TIMP biology in ovarian cancer may provide valuable insights in combating ovarian cancer progression and chemoresistance-mediated recurrence in patients.

The effect of the Progesterone-Induced Blocking Factor (PIBF) on E-cadherin expression, cell motility and invasion of primary tumour cell lines

In addition to being immunomodulatory, Progesterone-Induced Blocking Factor (PIBF) plays a role in cell cycle regulation and invasion. The full length protein is associated with the pericentriolar satellites and as such, it is crucial for maintaining the integrity of spindle poles during mitosis. Another suggestive evidence for the involvement of PIBF in tumour progression is the fact that the PIBF gene has been identified on chromosome 13 in the region associated with breast cancer susceptibility. Earlier we showed that PIBF differentially regulates the invasiveness of trophoblast and tumour cell lines. The aim of the present study was to further investigate the role of PIBF in tumour development, using primary ovarian- (OC) and primary lung carcinoma (LC) cell cultures, and JEG-3 choriocarcinoma cell line. In the cultured cells PIBF was knocked down by siRNA treatment, and the impact of PIBF deficiency on MMP-9 activity and E-cadherin expression as well as on invasive and migratory capacity of the cells was tested. In conditioned media of PIBF-deficient JEG-3 cells, LC cells and OC cells MMP-9 activity was reduced to 36% 35%, and 65% respectively compared to controls. Though PIBF knock down did not affect migration, in JEG-3 cells, LC primary cells and OC primary cells PIBF deficiency resulted 20%, 50% and 50% decrease of invasion respectively. PIBF silencing resulted in increased E-cadherin expression, suggesting that by down regulating E-cadherin expression, PIBF might interfere with the cell-cell adhesion mechanisms and by increasing MMP activity induced extracellular matrix degradation, facilitates the invasion of tumour cells.

Relationship between matrix metalloproteinases and the occurrence and development of ovarian cancer

Ovarian cancer is one of the most malignant genital cancers, with a high mortality rate. Many researchers have suggested that matrix metalloproteinases (MMPs) have remarkably high expression in ovarian cancer tissues. MMPs are considered to be related to the occurrence, development, invasion and metastasis of ovarian cancer. Moreover, some studies have discovered that the unbalance between MMPs and tissue inhibitor of metalloproteinases (TIMPs) are associated with the malignant phenotype of tumors. This review summarizes the latest research progress of MMPs in ovarian cancer. The investigation of MMP mechanism in ovarian cancer will facilitate the development of effective anti-tumor drugs, and thereby improve the survival rate of patients with ovarian cancer.

Knockdown of astrocyte elevated gene-1 inhibited cell growth and induced apoptosis and suppressed invasion in ovarian cancer cells

Emerging evidence has demonstrated that AEG-1 (astrocyte elevated gene-1) plays a pivotal oncogenic role in tumorigenesis. However, the molecular mechanism by which AEG-1 exerts its oncogenic function is elusive in ovarian cancer. To explore the role and molecular insight on AEG-1-mediated tumorigenesis in ovarian cancer, multiple approaches are performed including MTT assay, flow cytometry for apoptosis and cell cycle assay, gene transfection, real-time RT-PCR, Western blotting, and Transwell assay. Our MTT assay showed that knockdown of AEG-1 by its siRNA significantly inhibited cell growth in ovarian cancer cells. Moreover, AEG-1 siRNA treatment induced G₀/G₁ cell cycle arrest and triggered cell apoptosis in ovarian cancer cells. Notably, inhibition of AEG-1 suppressed cell migration and invasion in ovarian cancer cells. Intriguingly, we identified that knockdown of AEG-1 remarkably inhibited the activation of Akt pathway. Our results also validated that knockdown of AEG-1 inhibited the expression of MMP-2 and VEGF, which could lead to inhibition of cell migration and invasion. These data suggest that AEG-1 could be a potential therapeutic target for the treatment of ovarian cancer.

A pan-cancer analysis of secreted Frizzled-related proteins: re-examining their proposed tumour suppressive function

Secreted frizzled-related proteins (SFRPs), containing five family members (SFRPs 1-5) are putative extracellular Wnt inhibitors. Given their abilities to inhibit Wnt signalling, as well as the loss of SFRP1 in many cancers, this family is generally considered to be tumour suppressive. In this study we analyzed gene expression, promoter methylation and survival data from over 8000 tumour and normal samples from 29 cancers in order to map the context-specific associations of SFRPs 1-5 with patient survival, gene silencing and gene expression signatures. We show that only SFRP1 associates consistently with tumour suppressive functions, and that SFRP2 and SFRP4 typically associate with a poor prognosis concomitant with the expression of genes associated with epithelial-to-mesenchymal transition. Moreover, our results indicate that while SFRP1 is lost in cancer cells via the process of DNA methylation, SFRP2 and 4 are likely derived from the tumour stroma, and thus tend to increase in tumours as compared to normal tissues. This in-depth analysis highlights the need to study each SFRP as a separate entity and suggests that SFRP2 and SFRP4 should be approached as complex matricellular proteins with functions that extend far beyond their putative Wnt antagonistic ability.

Promotion of breast cancer cells MDA-MB-231 invasion by di(2-ethylhexyl)phthalate through matrix metalloproteinase-2/-9 overexpression

Di(2-ethylhexyl)phthalate (DEHP) is an estrogenic chemical that is widely used in polyvinyl products. We aimed to determine the mechanisms behind the effects of DEHP on ERα-negative breast cancer cells MDA-MB-231 invasion and matrix metalloproteinases-2/-9 (MMP-2/-9) up-regulation in this study. Transwell assay indicated that DEHP exposure (>50 μg/ml) significantly enhanced the invasion ability of MDA-MB-231 cells. Quantitative real-time PCR (qPCR) and western blotting revealed that MMP-2/-9 is overexpressed in mRNA and protein levels after DEHP treatment. Gelatin zymography consistently demonstrated that DEHP exposure also enhances the activity of MMP-2/-9. Immunofluorescence assay showed that DEHP could accelerate NF-kappaB (NF-κB) subunits-p65 translocation into the nucleus, which is confirmed by western blotting assay, suggesting that the ratio of nuclear/cytosolic level of p65 was significantly increased. Furthermore, the invasion and MMP-2/-9 overexpression of MDA-MB-231 cells after DEHP-treated were reversed by the NF-κB chemical inhibitor JSH-23 via drug inhibition assay. This study suggested that DEHP could promote ERα-negative breast cancer cells MDA-MB-231 invasion through activating NF-κB and MMP-2/-9 overexpression.