Pharmacological inhibition of EZH2 using a covalent inhibitor suppresses human ovarian cancer cell migration and invasion

Metastasis is the cause of poor prognosis in ovarian cancer (OC). Enhancer of Zeste homolog 2 (EZH2), a histone-lysine N-methyltransferase enzyme, promotes OC cell migration and invasion by regulating the expression of tissue inhibitor of metalloproteinase-2 (TIMP2) and matrix metalloproteinases-9 (MMP9). Hence, we speculated that EZH2-targeting therapy might suppress OC migration and invasion. In this study, the expression of EZH2, TIMP2, and MMP9 in OC tissues and cell lines was analyzed using The Cancer Genome Atlas (TCGA) database and western blotting, respectively. The effects of SKLB-03220, an EZH2 covalent inhibitor, on OC cell migration and invasion were investigated using wound-healing assays, Transwell assays, and immunohistochemistry. TCGA database analysis confirmed that the EZH2 and MMP9 mRNA expression was significantly higher in OC tissues, whereas TIMP2 expression was significantly lower than that in normal ovarian tissues. Moreover, EZH2 negatively correlated with TIMP2 and positively correlated with MMP9 expression. In addition to the anti-tumor activity of SKLB-03220 in a PA-1 xenograft model, immunohistochemistry results showed that SKLB-03220 markedly increased the expression of TIMP2 and decreased the expression of MMP9. Additionally, wound-healing and Transwell assays showed that SKLB-03220 significantly inhibited the migration and invasion of both A2780 and PA-1 cells in a concentration-dependent manner. SKLB-03220 inhibited H3K27me3 and MMP9 expression and increased TIMP2 expression in PA-1 cells. Taken together, these results indicate that the EZH2 covalent inhibitor SKLB-03220 inhibits metastasis of OC cells by upregulating TIMP2 and downregulating MMP9, and could thus serve as a therapeutic agent for OC.

Association of TIMP2 418 G/C and MMP Gene Polymorphism with Risk of Urinary Cancers: Systematic Review and Meta-analysis

Aim: The matrix metalloproteinases (MMPs) inhibit tissue inhibitors of metalloproteinases (TIMPs), playing a notable role in various biological processes, and mutations in TIMP2 genes impact a variety of urinary cancers. In this study, we analyze and evaluate the potential involvement of the TIMP2 418 G/C and MMP gene polymorphism in the etiology of urinary cancer. Methodology: For suitable case-control studies, a literature search was undertaken from various database sources such as PubMed, EMBASE, and Google Scholar. Incorporated into the analysis were case-control or cohort studies that documented the correlation between TIMP2 418 G/C and urological cancers. MetaGenyo served as the tool for conducting the meta-analysis, employing a fixed-effects model. The collective odds ratios, along with their corresponding 95% confidence intervals, were calculated and presented to assess the robustness of the observed associations. Results: A total of seven studies involving controls and cases out of recorded 1265 controls and 1154 cases were analyzed to ascertain the significant association of the TIMP2 gene with urologic cancer. No statistically significant correlation was observed between allelic, recessive, dominant, and overdominant models for the genetic variant under investigation. A 95% confidence interval (CI) and odds ratio (OR) were computed for each model, considering p-values <0.05. The OR and 95% CI for the allelic model were 0.99 and 0.77-1.27, respectively, whereas the respective values were 1.00 and 0.76-1.32 for the recessive model. In the dominant contrast model, OR and 95% CI were 1.09 and 0.62-1.90, while the same were 0.93 and 0.77-1.12 for the overdominant model. A funnel plot was used to reanalyze and detect the results as statically satisfactory. Conclusions: As a result of the data obtained, the TIMP2 gene polymorphism does not correlate statistically with cancer risk. The significance of this finding can only be confirmed using a large population, extensive epidemiological research, a comprehensive survey, and a better understanding of the molecular pathways associated.

The association between activation of the ERK1/2-NF-κB signaling pathway by TIMP2 expression and chronic renal allograft dysfunction in the CRAD rat model

PURPOSE

The tissue inhibitor of metalloproteinase 2 (TIMP2), a natural inhibitor of matrix metalloproteinase (MMP), regulates inflammation, fibrosis, and cell proliferation. Chronic renal allograft dysfunction (CRAD) is a primary factor affecting the long-term survival of renal allografts. We assessed whether up-regulation of TIMP2 expression may affect the ERK1/2-NF-κB signaling pathway and CRAD development.

METHODS

Lewis rats received orthotopic F344 kidney allografts to establish the classical CRAD model. The treatment group was injected with a lentivirus encoding a TIMP2-targeting small hairpin (sh)RNA (LTS) at 5 × 108 TU/ml monthly after kidney transplantation. A second CRAD group was injected with a lentivirus TIMP2-control vector (LTC). After 12 weeks, blood, urine, and kidney tissue were harvested to evaluate renal function and pathological examinations. Hematoxylin and eosin staining, Masson staining, and Periodic acid-Schiff staining were performed for renal histopathological evaluation according to the Banff criteria. TIMP2, phospho (p)-ERK1/2, p-p65 (NF-κB) expression levels were measured via immunohistochemical and Western blot analyses.

RESULTS

Compared to the F344 and Lewis control groups, the expression of TIMP2, p-ERK1/2, and p-p65 were significantly higher in the CRAD and CRAD+LTC renal tissues (p < 0.05). There were also increased levels of serum creatinine, nitrogen, and 24 h urinary protein in these two groups (p < 0.05). Typical histopathological changes of CRAD were observed in the CRAD and CRAD+LTC groups. Administration of LTS effectively decreased the expression of TIMP2, p-ERK1/2, and p-P65, and reduced interstitial fibrosis and macrophage infiltration in the treatment group (p < 0.05). Additionally, MCP1 and ICAM-1, which are downstream cytokines of the NF-κB pathway, were also inhibited in the renal rat kidney from the LTS group (p < 0.05). Furthermore, renal function was well preserved in the LTS group compared to the CRAD group and CRAD+LTC group.

CONCLUSION

A decrease of TIMP2 can alleviate the progression of inflammation in CRAD via inhibition of the ERK1/2-NF-κB signaling pathway.

Is the Synovium the First Responder to Posttraumatic Knee Joint Stress? The Molecular Pathogenesis of Traumatic Cartilage Degeneration

OBJECTIVE

The aim of this study was to evaluate if a similar catabolic and inflammatory gene pattern exists between the synovium, hyaline cartilage, and blood of patients with the knee joint tissues and if one precedes the other.

DESIGN

A total of fifty-eight patients (34 females and 24 males) with a mean age of 44.7 years (range, 18-75) underwent elective knee arthroscopy due to previously diagnosed pathology. Full blood samples were collected preoperatively from synovium and cartilage samples intraoperatively. Real time PCR with spectrophotometric analysis was performed. Following genes taking part in ECM (extracellular matrix) remodeling were selected for analysis: MMP-1, MMP-2, MMP-8, MMP-9, MMP-13, MMP-14, ADAMTS-4 (Agg1) and ADAMTS-5 (Agg2) proteases, TIMP-1, and TIMP-2 - their inhibitors - and IL-1 and TNF-α cytokines.

RESULTS

Analysis revealed a strong and significant correlation between gene expression in synovial and systemic blood cells (p <0.05 for all studied genes) with ADAMTS-4, ADAMTS-5, IL-1, TNF-α and TIMP-2 expression most positively correlated with an R>0.8 for each. An analysis between chondrocytes and systemic blood gene expression shown no significant correlation for all genes. Bivariate correlation of International Cartilage Repair Society grading and genes expression revealed significant associations with synovial MMP-1, MMP-2, MMP-8, MMP-9, IL-1, TNF-α and TIMP-2.

CONCLUSION

We suggest that the synovial tissue is the first responder for knee joint stress factors in correlation with the response of blood cells. The chondrocyte's genetic response must be further investigated to elucidate the genetic program of synovial joints, as an organ, during OA development and progression.

Trophoblast cellular adhesion molecule expression regulated by different genes and their correlation with pregnancy-induced hypertension

It was to study trophoblast cell (TC) adhesion molecules regulated by different genes in the placental tissue (PT) of patients with pregnancy-induced hypertension (PIH), and the correlation with the severity of PIH. 42 patients with PIH (13 cases in the mild PIH group, 11 cases in the moderate PIH group, and 18 cases in the severe PIH group) and 40 patients with normal pregnancy (NP group) were included. mRNA and protein levels in matrix metalloproteinase (MMP)-9, MMP-2, tissue inhibitor of metalloproteinases (TIMP)-1, and TIMP-2 of all patients were determined by semi-quantitative polymerase chain reaction (PCR) and Western blotting (WB), respectively. Compared to the NP group, MMP-9 and MMP-2 mRNA levels as well as their proteins in PT significantly decreased in PIH groups (P<0.05). MMP-9 mRNA was greatly lower in the severe PIH group than mild PIH group (P<0.05). MMP-2 mRNA in moderate and severe PIH groups was much lower than NP and mild PIH groups, and that in the severe PIH group was considerably lower than the moderate PIH group (P<0.05). TIMP-1 mRNA and its protein highly increased in PT in PIH groups than NP group (P<0.05). TIMP-2 mRNA was remarkably higher in the severe PIH group than in the NP group (P<0.05). mRNA and proteins of MMP-9 and MMP-2 decreased in PT of PIH patients, while TIMP-1 mRNA and its protein increased, which were correlated with the severity of PIH. MMP-9, MMP-2, and TIMP-1 were involved in the pathogenesis of PIH by regulating the infiltration of TCs.

TIMP2 ameliorates blood-brain barrier disruption in traumatic brain injury by inhibiting Src-dependent VE-cadherin internalization

Blood-brain barrier (BBB) disruption is a serious pathological consequence of traumatic brain injury (TBI), for which there are limited therapeutic strategies. Tissue inhibitor of metalloproteinase-2 (TIMP2), a molecule with dual functions of inhibiting MMP activity and displaying cytokine-like activity through receptor binding, has been reported to inhibit VEGF-induced vascular hyperpermeability. Here, we investigate the ability of TIMP2 to ameliorate BBB disruption in TBI and the underlying molecular mechanisms. Both TIMP2 and AlaTIMP2, a TIMP2 mutant without MMP-inhibiting activity, attenuated neurological deficits and BBB leakage in TBI mice; they also inhibited junctional protein degradation and translocation to reduce paracellular permeability in human brain microvascular endothelial cells (ECs) exposed to hypoxic plus inflammatory insult. Mechanistic studies revealed that TIMP2 interacted with α3β1 integrin on ECs, inhibiting Src activation-dependent VE-cadherin phosphorylation, VE-cadherin/catenin complex destabilization, and subsequent VE-cadherin internalization. Notably, localization of VE-cadherin on the membrane was critical for TIMP2-mediated EC barrier integrity. Furthermore, TIMP2-mediated increased membrane localization of VE-cadherin enhanced the level of active Rac1, thereby inhibiting stress fiber formation. All together, our studies have identified an MMP-independent mechanism by which TIMP2 regulates EC barrier integrity after TBI. TIMP2 may be a therapeutic agent for TBI and other neurological disorders involving BBB breakdown.

Expression analysis of MMP14: Key enzyme action in modulating visceral adipose tissue plasticity in patients with obesity

Compromised adipose tissue plasticity is a hallmark finding of obesity orchestrated by the intricate interplay between various extracellular matrix components. Collagen6 (COL6) is well characterized in obese visceral adipose tissue (VAT), not much is known about MMP14 which is hypothesized to be the key player in matrix reorganization. Subjects with obesity (BMI ≥40; n = 50) aged 18-60 years undergoing bariatric surgery and their age-matched controls (BMI < 25; n = 30) were included. MMP14, Col6A3 and Tissue inhibitor of metalloproteinase 2 (TIMP2) mRNA expression was assessed in VAT and their serum levels along with endotrophin were estimated in both groups preoperatively and post-operatively in the obese group. The results were analysed statistically and correlated with anthropometric and glycaemic parameters, namely fasting glucose and insulin, HbA1c, HOMA-IR, HOMA-β and QUICKI. Circulating levels as well as mRNA expression profiling revealed significant differences between the individuals with and without obesity (p < .05), more so in individuals with diabetes and obesity (p < .05). Follow-up serum analysis revealed significantly raised MMP14 (p < .001), with decreased Col6A3, endotrophin and TIMP2 levels (p < .01, p < .001 and p < .01, respectively). A rise in serum MMP14 protein, simultaneous with post-surgical weight loss and decreased serum levels of associated extracellular matrix (ECM) remodellers, suggests its crucial role in modulating obesity-associated ECM fibrosis and pliability of VAT.

Neuronal TIMP2 regulates hippocampus-dependent plasticity and extracellular matrix complexity

Functional output of the hippocampus, a brain region subserving memory function, depends on highly orchestrated cellular and molecular processes that regulate synaptic plasticity throughout life. The structural requirements of such plasticity and molecular events involved in this regulation are poorly understood. Specific molecules, including tissue inhibitor of metalloproteinases-2 (TIMP2) have been implicated in plasticity processes in the hippocampus, a role that decreases with brain aging as expression is lost. Here, we report that TIMP2 is highly expressed by neurons within the hippocampus and its loss drives changes in cellular programs related to adult neurogenesis and dendritic spine turnover with corresponding impairments in hippocampus-dependent memory. Consistent with the accumulation of extracellular matrix (ECM) in the hippocampus we observe with aging, we find that TIMP2 acts to reduce accumulation of ECM around synapses in the hippocampus. Moreover, its deletion results in hindrance of newborn neuron migration through a denser ECM network. A novel conditional TIMP2 knockout (KO) model reveals that neuronal TIMP2 regulates adult neurogenesis, accumulation of ECM, and ultimately hippocampus-dependent memory. Our results define a mechanism whereby hippocampus-dependent function is regulated by TIMP2 and its interactions with the ECM to regulate diverse processes associated with synaptic plasticity.

Dznep, a histone modification inhibitor, inhibits HIF1α binding to TIMP2 gene and suppresses TIMP2 expression under hypoxia

Epidemiological studies have shown that patients who recovered from acute kidney injury (AKI) may subsequently develop chronic kidney disease (CKD). AKI is primarily caused by renal hypoxia, and it causes epigenetic alterations, known as hypoxic memory. 3-Deazaneplanocin A (Dznep), an inhibitor of histone modification, suppresses renal fibrosis and the expression of tissue inhibitor of metalloproteinases-2 (TIMP2), a profibrotic factor, in mouse ischemia-reperfusion models. The current study investigated the epigenetic regulation of TIMP2 in human kidney 2 (HK-2) cells. The expression of TIMP2 was upregulated in HK-2 cells under hypoxic conditions and was suppressed by Dznep. ChIP-qPCR showed that Dznep reduced the amount of H3K4me3 at the promoter region of the TIMP2 gene under hypoxic condition. Formaldehyde-assisted isolation of regulatory elements-qPCR of the TIMP2 gene showed that Dznep reduced open chromatin area. In addition, based on ChIP-qPCR of hypoxia-inducible factor 1 alpha (HIF1α), Dznep inhibited the binding of HIF1α to the TIMP2 gene under hypoxic conditions. The reporter assays for the binding region of HIF1α showed enhanced transcriptional activity by hypoxia. Dznep suppresses the expression of TIMP2 under hypoxic conditions by inhibiting the binding of HIF1α to the TIMP2 gene.

TIMP2 facilitates CIRI through activating NLRP3-mediated pyroptosis

This study aimed to investigate the underlying mechanisms of cerebral ischemia-reperfusion injury (CIRI) in mice using CIR and hypoxia/reoxygenation (H/R) cell models. The study evaluated brain tissue weight, pathological injury, and changes in the expression levels of TIMP2, p-ERK1/2 and NLRP3-mediated pyroptosis-related proteins in brain tissues and hippocampal neurons of CIR mice using established methods such as dry/wet weight measurement, HE staining, qPCR, TUNEL assay, and Western blotting. The results demonstrated a significant increase in brain water content and neuronal apoptosis rate in the experimental groups compared with those in the control group. In particular, the I/R+TIMP2 group showed the highest increase. Additionally, the control group exhibited a clear brain tissue structure, neatly and densely arranged cells with normal morphology, and evenly stained and clear hippocampal tissues. However, the I/R group showed hippocampal structure disorders, interstitial edema, deep nuclear staining, karyopyknosis, and karyorrhexis in brain tissues. The study results further revealed that TIMP2 could aggravate the pathological damage of brain tissues in the I/R+TIMP2 group compared with the I/R group and significantly reduced it in the TIMP2-KD group. Furthermore, the Western blotting results demonstrated that the protein expression levels of TIMP2, p-ERK1/2, t-ERK1/2, NLRP3, IL-1β, IL-18, GSDMD, Caspase-1, and ASC in brain tissues and hippocampal neurons were significantly higher in the experimental groups than those in the control group. The I/R+TIMP2 group displaying the highest increase and the TIMP2-KD group showing a significant decrease. In conclusion, TIMP2 can contribute to the occurrence and progression of CIRI by activating NLRP3-mediated pyroptosis.

Poly-L-Lactic acid increases collagen gene expression and synthesis in cultured dermal fibroblast (Hs68) through the TGF-β/Smad pathway

OBJECTIVE

Poly-L-Lactic Acid (PLLA) is a synthetic polymer which possesses biocompatible and biodegradable properties, and is widely used in the clinical filler material. This study focuses on the potential role of PLLA on the collagen production of dermal fibroblasts and its mechanism.

METHODS

The dermal fibroblast Hs60 was treated with different concentration of PLLA. RT-qPCR was conducted for the determination of mRNA levels of collagen type I (COL1) alpha 1 (COL1A1), COL1 alpha 2 (COL1A2), elastin, matrix metalloproteinase 1 (MMP-1), tissue inhibitor of metalloproteinase 1 (TIMP-1), and TIMP-2. Procollagen Type I C-peptide (PIP) enzyme immunoassay (EIA) Kit assay was carried out to analyze procollagen production. Western Blot was employed to examine the effect of PLLA and transforming frown factor (TGF-β) receptor-specific inhibitor (SB431542) on protein levels of COL1A1 and TGF-β/Smad signaling pathway related proteins.

RESULTS

With the increase of PLLA concentration, the production of procollagen gradually increased, and both protein and mRNA levels of COL1A1 and COL1A2 gradually increased (p < 0.001). Elevated PLLA concentrations increased elastin, TIMP-1, and TIMP-2 levels and attenuated MMP-1 expression. PLLA increased TGF-β levels in a dose-dependently manner. p-Smad2 and p-Smad3 protein levels were also increased by PLLA, but the influences were reversed by SB431542 (p < 0.001). Similarly, increased levels of COL1A1, COL1A2, TIMP-1, and TIMP-2 caused by PLLA were significantly inhibited by SB431542, whereas MMP-1 was typically elevated (p < 0.001).

CONCLUSION

Poly-L-Lactic Acid promotes the collagen production of dermal fibroblasts by activating the TGF-β/Smad signaling pathway. The findings may lay a foundation for clinical material applications of PLLA.

Utilizing genetic code expansion to modify N-TIMP2 specificity towards MMP-2, MMP-9, and MMP-14

Matrix metalloproteinases (MMPs) regulate the degradation of extracellular matrix (ECM) components in biological processes. MMP activity is controlled by natural tissue inhibitors of metalloproteinases (TIMPs) that non-selectively inhibit the function of multiple MMPs via interaction with the MMPs' Zn2+-containing catalytic pocket. Recent studies suggest that TIMPs engineered to confer MMP specificity could be exploited for therapeutic purposes, but obtaining specific TIMP-2 inhibitors has proved to be challenging. Here, in an effort to improve MMP specificity, we incorporated the metal-binding non-canonical amino acids (NCAAs), 3,4-dihydroxyphenylalanine (L-DOPA) and (8-hydroxyquinolin-3-yl)alanine (HqAla), into the MMP-inhibitory N-terminal domain of TIMP2 (N-TIMP2) at selected positions that interact with the catalytic Zn2+ ion (S2, S69, A70, L100) or with a structural Ca2+ ion (Y36). Evaluation of the inhibitory potency of the NCAA-containing variants towards MMP-2, MMP-9 and MMP-14 in vitro revealed that most showed a significant loss of inhibitory activity towards MMP-14, but not towards MMP-2 and MMP-9, resulting in increased specificity towards the latter proteases. Substitutions at S69 conferred the best improvement in selectivity for both L-DOPA and HqAla variants. Molecular modeling provided an indication of how MMP-2 and MMP-9 are better able to accommodate the bulky NCAA substituents at the intermolecular interface with N-TIMP2. The models also showed that, rather than coordinating to Zn2+, the NCAA side chains formed stabilizing polar interactions at the intermolecular interface with MMP-2 and MMP-9. Our findings illustrate how incorporation of NCAAs can be used to probe-and possibly exploit-differential tolerance for substitution within closely related protein-protein complexes as a means to improve specificity.

Ex Vivo Analysis of an Association of Mechanical Strength of Dilated Ascending Aorta with Tissue Matrix Metalloproteinases and Cytokines

We analyzed the associations of the mechanical strength of dilated ascending aorta wall (intraoperative samples from 30 patients with non-syndromic aneurysms) with tissue MMPs and the cytokine system. Some samples were stretched to break on an Instron 3343 testing machine and the tensile strength was calculated; others were homogenized and the concentrations of MMP-1, MMP-2, MMP-7, their inhibitors (TIMP-1 and TIMP-2), and pro- and anti-inflammatory cytokines were determined by ELISA. Direct correlations between aortic tensile strength and concentrations of IL-10 (r=0.46), TNFα (r=0.60), and vessel diameter (r=0.67) and an inverse correlation with patient's age (r=-0.59) were revealed. Compensatory mechanisms supporting the strength of the ascending aortic aneurysm are possible. No associations of MMP-1, MMP-7, TIMP-1, and TIMP-2 with tensile strength and aortic diameter were found.

Effects of TIMP-2 Polymorphisms on Retinopathy of Prematurity Risk, Severity, Recurrence, and Treatment Response

Tissue inhibitors of metalloproteinases (TIMPs) play a crucial role in endogenous angiogenesis besides the regulation of matrix metalloproteinase (MMP) activity. Associations between TIMP-2 gene polymorphisms and the risk of retinopathy of prematurity (ROP) were examined. Premature infants born between 2009 and 2018 were included. Five single-nucleotide polymorphisms (SNPs) of TIMP-2 were analyzed with real-time polymerase chain reaction (PCR). Multivariate logistic regression was applied to model associations between TIMP-2 polymorphisms and ROP susceptibility and severity. The GA+AA genotype in individuals with the TIMP-2 polymorphism of rs12600817 was associated with a higher risk of ROP (odds ratio [OR]: 1.518, 95% confidence interval [CI]: 1.028-2.242) compared with their wild-type genotypes. The AA genotype (OR: 1.962, 95% CI: 1.023-3.762) and the AA+GA genotype (OR: 1.686, 95% CI: 1.030-2.762) in individuals with the rs12600817 polymorphism had higher risks of severe, treatment-requiring ROP relative to their wild-type counterparts. In patients with treatment-requiring ROP, the AG+GG genotypes in the TIMP-2 polymorphism of rs2889529 were correlated with the treatment response (p = 0.035). The TIMP-2 polymorphism of rs12600817 help in predicting ROP risks in preterm infants, while the polymorphism of rs2889529 can serve as a genetic marker in evaluating the ROP treatment response.

TIMP-1 expression in coronary thrombi associate with myocardial injury in ST-elevation myocardial infarction patients

BACKGROUND

Matrix metalloproteinases (MMPs) and their inhibitors (TIMPs) are considered important both in atherosclerosis and remodeling after acute myocardial infarction (AMI). We aimed to study genetic expression and presence of MMP-2, MMP-9, TIMP-1, TIMP-2 and the extracellular MMP-inducer (EMMPRIN) in coronary thrombi. Circulating levels and genetic expression in circulating leukocytes were also assessed, and relations to degree of myocardial injury measured by troponin T and time from symptom to PCI were explored. Expression of cell markers were also analyzed, indicating relations to cell types.

METHODS

Intracoronary thrombi were aspirated from 33 patients with ST-elevation myocardial infarction (STEMI). Blood samples with Pax-gene tubes were drawn at end of PCI and the next day. RNA was isolated from thrombi and leukocytes, and genes were relatively quantified by RT-PCR. Each thrombus was preserved for histology and immunohistochemistry analyzes.

RESULTS

Genes coding for the five markers were present in 84-100% of thrombi and immunohistochemically stained in 96-100%. Expression of TIMP-1 in thrombi and in leukocytes correlated significantly to peak troponin T ( r = 0.393 P = 0.026, r = 0.469 P = 0.006, respectively). No significant correlations between genes expressed in thrombi and time from symptom to PCI were observed. TIMP-1 was connected mainly to monocytes/macrophages in the thrombi.

CONCLUSION

MMP-2, MMP-9, TIMP-1, TIMP-2 and EMMPRIN were highly expressed in human coronary thrombi. The correlation between troponin T and the expression of TIMP-1 both in thrombi and in leukocytes at time of PCI indicates that TIMP-1 plays a role in myocardial damage early post-MI.

The Role of Tissue Inhibitor of Metalloproteinase-1 and 2 in Echinococcus granulosus senso lato-Induced Human Hepatic Fibrosis

INTRODUCTION

The main mechanism underlying hepatic fibrosis is the imbalance between tissue Matrix Metalloproteinases (MMPs) and Tissue Inhibitors of Metalloproteinases (TIMPs). This study aimed to investigate the potential role of TIMP-1 and TIMP-2 in the process of hepatic fibrosis caused by Echinococcus granulosus senso lato (E. granulosus s.l.).

METHODS

The expressions levels of TIMP-1 and TIMP-2 mRNAs were evaluated in fibrotic and normal hepatic tissues of 30 patients with Cystic Echinococcus (CE) using qRT-PCR. Moreover, their serum levels of TIMP-1 were assessed before CE cyst removal and 6 months after surgery using ELISA.

RESULTS

The qRT-PCR results showed that the expression levels of TIMP-1 and TIMP-2 mRNAs were significantly higher in the fibrotic hepatic tissue compared to the normal liver tissue, in a way that the TIMP-1 and TIMP-2 mRNA expression levels were 19.07 and 6.58 folds higher in the fibrotic tissue compared to the normal liver tissue. Among these TIMPs, TIMP-1 exhibited the higher area under the curve (AUC) value for predicting liver fibrosis. However, we could not find a significant difference in the serum levels of TIMP-1 before and after the cyst removal procedure (p = 0.48).

CONCLUSIONS

For the first time, our study showed that the significant overexpression of both TIMP mRNAs in the fibrotic liver tissue of the CE patients may be due to the increased expression of MMPs in the peri-cystic tissue. However, we could not find a significant difference in the pre- and post-operative TIMP-1 levels, which may be due to recurrence or heterogeneity in the cyst type. Therefore, performing further studies with a larger sample size of the CE patients is recommended.

USP7 inhibits TIMP2 by up-regulating the expression of EZH2 to activate the NF-κB/PD-L1 axis to promote the development of cervical cancer

BACKGROUND

Cervical cancer belongs to the most common gynecological malignant cancers. EZH2 has been found to be dysregulated in different kinds of tumors and acts as an oncogene to promote cancer development. However, its upstream regulators and downstream targets in cervical cancer remain unclear. PD-L1 is a surface marker of cancer cells, facilitating the immunosuppressive microenvironment for escape from immunity attack. The molecular mechanism of increased PD-L1 expression in cervical cancer is needed to be explored.

METHODS

The expression levels of USP7, EZH2 and TIMP2 in cervical cancer patients' samples and cell lines were detected by qRT-PCR and histopathology staining. The functions of USP7, EZH2 and TIMP2 were evaluated by MTT, cell migration and invasion assays after knocking down or overexpression of indicated genes. The tumor microenvironment was determined by testing of PD-L1 expression and cytotoxicity when co-cultured with NK-92 cells. Xenograft model was used to test the function of USP7 in vivo.

RESULTS

Our data demonstrated that USP7 and EZH2 were upregulated in cervical cancer, while TIMP2 was downregulated. Inhibition of USP7 and EZH2, or overexpression of TIMP2 suppressed proliferation, migration, invasion and immune escape ability of cervical cancer cells. USP7 could increase EZH2 level, which in turn inhibited TIMP2 expression via methylation in its promoter. TIMP2 was able to mediate PD-L1 expression via NF-κB signaling pathway. Knocking down of USP7 could inhibit tumor development in vivo of cervical cancer.

CONCLUSIONS

The study discovered the function and mechanism of USP7 and highlighted its oncogenic role in cervical cancer development. Our results indicated that targeting USP7 could be a therapeutic strategy the treatment of cervical cancer.

[The myocardial protective effect of propofol on rats with experimental myocardial infarction and its mechanism]

The aim of the present study was to investigate the protective effect of propofol on the experimental myocardial infarction in rats. The myocardial infarction model was established by ligating the anterior descending branch of left coronary artery in rats. Model rats were treated with propofol. Cardiac function was evaluated by echocardiography. Cardiac hemodynamic changes were detected by multiconductor biorecorder. Pathological changes in the infarcted myocardia were detected by HE staining. The expression levels of cardiac hypertrophy marker genes and fibrosis marker proteins were analyzed by real-time quantitative PCR and Western blot. The results showed that, compared with the sham surgery group, the model group exhibited larger infarct size (> 40%), impaired heart function, and significantly increased left ventricular end-diastolic pressure (LVEDP). Propofol reduced cardiac function impairment and decreased LVEDP in the model group. Propofol significantly reduced lung weight/body weight ratio, heart weight/body weight ratio, left ventricular weight/body weight ratio and left atrial weight/body weight ratio in the model group. Furthermore, after myocardial infarction, the administration of propofol significantly improved the diastolic strain rate, down-regulated the mRNA expression levels of myocardial hypertrophy markers, atrial natriuretic peptide and β-myosin heavy chain, and reversed the up-regulation of matrix metalloproteinase 2 (MMP2), MMP9 and tissue inhibitor of metalloproteinase-2 (TIMP-2) induced by myocardial infarction. These results suggest propofol can reduce adverse ventricular remodeling, cardiac dysfunction, myocardial hypertrophy and fibrosis after myocardial infarction, and has protective effect against the experimental myocardial infarction induced by coronary artery ligation in rats.

Integrated Multi-Omics Investigations of Metalloproteinases in Colon Cancer: Focus on MMP2 and MMP9

Colorectal cancer (CRC) develops by genetic and epigenetic alterations. However, the molecular mechanisms underlying metastatic dissemination remain unclear and could benefit from multi-omics investigations of specific protein families. Matrix metalloproteinases (MMPs) are proteolytic enzymes involved in ECM remodeling and the processing of bioactive molecules. Increased MMP expression promotes the hallmarks of tumor progression, including angiogenesis, invasion, and metastasis, and is correlated with a shortened survival. Nevertheless, the collective role and the possible coordination of MMP members in CRC are poorly investigated. Here, we performed a multi-omics analysis of MMP expression in CRC using data mining and experimental investigations. Several databases were used to deeply mine different expressions between tumor and normal tissues, the genetic and epigenetic alterations, the prognostic value as well as the interrelationships with tumor immune-infiltrating cells (TIICs). A special focus was placed on to MMP2 and MMP9: their expression was correlated with immune markers and the interaction network of co-expressed genes disclosed their implication in epithelial to mesenchymal transition (EMT) and immune response. Finally, the activity levels of MMP2 and MMP9 in a cohort of colon cancer samples, including tissues and the corresponding sera, was also investigated by zymography. Our findings suggested that MMPs could have a high potency, as they are targeted in colon cancer, and might serve as novel biomarkers, especially for their involvement in the immune response. However, further studies are needed to explore the detailed biological functions and molecular mechanisms of MMPs in CRC, also in consideration of their expression and different regulation in several tissues.

ESR1 mediated circ_0004018 suppresses angiogenesis in hepatocellular carcinoma via recruiting FUS and stabilizing TIMP2 expression

Angiogenesis has been certified to account for tumor pathobiology. Circular RNAs (circRNAs) have been demonstrated to be involved in angiogenesis-related diseases, including hepatocellular carcinoma (HCC). Nevertheless, the regulatory roles of most circRNAs remain obscure. This study aims to uncover the function of hsa_circ_0004018 on angiogenesis in HCC. Firstly, quantitative real-time RT-PCR (RT-qPCR) analyzed that circ_0004018 was definitely down-regulated in HCC. Western blot analysis was conducted to detect the protein level of fused protein in sarcoma (FUS) and TIMP metallopeptidase inhibitor 2 (TIMP2). Functional assays were carried out to assess the impacts of circ_0004018 on HCC. From the experimental results, we found that overexpression of circ_0004018 significantly inhibited angiogenesis in HCC. The regulatory mechanism of circ_0004018 in HCC was determined by chromatin immunoprecipitation (ChIP), luciferase reporter assays and RNA immunoprecipitation (RIP) assay. Therefore, we proved that estrogen receptor 1 (ESR1) mediated circ_0004018 regulated TIMP2 by recruiting FUS. A series of rescue assays verified that circ_0004018 participated in angiogenesis in HCC via modulating TIMP2. In summary, this paper disclosed that ESR1 activated circ_0004018 inhibited angiogenesis in HCC via binding to FUS and stabilizing TIMP2 expression.

Effect of sugar metabolite methylglyoxal on equine lamellar explants: An ex vivo model of laminitis

Laminitis is one of the most devastating diseases in equine medicine, and although several etiopathogenetic mechanisms have been proposed, few clear answers have been identified to date. Several lines of evidence point towards its underlying pathology as being metabolism-related. In the carbonyl stress pathway, sugars are converted to methylglyoxal (MG)-a highly reactive α-oxoaldehyde, mainly derived during glycolysis in eukaryotic cells from the triose phosphates: D-glyceraldehyde-3-phosphate and dihydroxyacetone phosphate. One common hypothesis is that MG could be synthesized during the digestive process in horses, and excessive levels absorbed into peripheral blood could be delivered to the foot and lead to alterations in the hoof lamellar structure. In the present study, employing an ex vivo experimental design, different concentrations of MG were applied to hoof explants (HE), which were then incubated and maintained in a specific medium for 24 and 48 h. Macroscopic and histological analyses and a separation force test were performed at 24 and 48 h post-MG application. Gene expression levels of matrix metalloproteinase (MMP)-2 and -14 and tissue inhibitor of metalloproteinase (TIMP)-2 were also measured at each time point for all experimental conditions. High concentrations of MG induced macroscopic and histological changes mimicking laminitis. The separation force test revealed that hoof tissue samples incubated for 24 h in a high concentration of MG, or with lower doses but for a longer period (48 h), demonstrated significant weaknesses, and samples were easily separated. All results support that high levels of MG could induce irreversible damage in HEs, mimicking laminitis in an ex vivo model.

Small extracellular vesicles secreted by vaginal fibroblasts exert inhibitory effect in female stress urinary incontinence through regulating the function of fibroblasts

Stress urinary incontinence (SUI) is a common condition in women and associated with extra-cellular matrix (ECM) reconstruction, which is mainly regulated by fibroblasts. However, the underlying mechanism remains obscure. Small extracellular vesicles (sEVs) play fundamental biological roles in various cellular functions. Some studies suggested that the sEVs were involved in the metabolism of ECM and the function of fibroblasts. The purpose of our study was to investigate the effect of sEVs secreted by vaginal fibroblasts on the pathogenesis of SUI. We showed that the fibroblasts of female anterior vaginal wall secreted sEVs. Moreover, fibroblasts of females with SUI had significantly elevated secretion of sEVs. The collagen contents, proliferation and migration capacity of fibroblasts were decreased when fibroblasts were co-cultured with fibroblasts-derived sEVs (fibroblast-sEVs) from SUI patients. Proteomic analysis revealed that fibroblast-sEVs contained various differentially expressed proteins including TIMP2, TGF-β and ABCC4, which were involved in signaling pathways of fibroblasts regulation. Therefore, we suggested that fibroblast-sEVs contributed to the pathogenesis of SUI through various proteins including TIMP2, TGF-β and ABCC4.

Effect of TIMP2/TIMP3 genes on the risk of osteosarcoma in Zhejiang population

Osteosarcoma is a malignant tumor that develops from a mesenchymal cell line and is caused by gene-environment interactions. This study aimed to explore whether TIMP2/TIMP3 polymorphisms influenced the osteosarcoma risk.The expression of the TIMP2 and TIMP3 genes in osteosarcoma histiocytes was analyzed by immunohistochemistry. In this case-control study, which includes samples from 499 patients and 500 healthy controls, 10 single-nucleotide polymorphisms (SNPs) in TIMP2 and TIMP3 were selected. Furthermore, we used the Agena MassARRAY platform for genotyping. The statistical analysis was performed using χ2 test/Fisher exact test, and logistic regression analysis.The immunohistochemistry results showed that the expression of TIMP2 is obvious higher in osteosarcoma histiocytes than in the normal histiocytes. The association study indicated that the allele of rs2277698 and rs4789936 were protective SNPs reducing the risk of osteosarcoma (odds ratios  > 1, P < .05) by the χ2 test. In the genetic model, logistic regression analyses revealed that the rs2277698 and rs4789936 were associated with decreasing the risk of osteosarcoma under the codominant model, dominant model, and log-additive model. Stratification analysis revealed that 2 SNPs (rs2277698 and rs4789936) were significantly associated with a reduced risk of osteosarcoma in allele and genetic model after stratification by gender or age (P < .05). In addition, the haplotype "Trs2277698Crs2009169Crs7342880" of TIMP2 was associated with decreasing the osteosarcoma risk. The "Ars9609634Trs11547635" of TIMP3 was associated with reducing the osteosarcoma risk.This finding shed new light on the high expression of TIMP2 polymorphisms may contribute to decreasing the osteosarcoma risk in Zhejiang populations.

HNRNPA1-mediated exosomal sorting of miR-483-5p out of renal tubular epithelial cells promotes the progression of diabetic nephropathy-induced renal interstitial fibrosis

Diabetic nephropathy (DN) is a serious complication in type 1 and type 2 diabetes, and renal interstitial fibrosis plays a key role in DN progression. Here, we aimed to probe into the role and potential mechanism of miR-483-5p in DN-induced renal interstitial fibrosis. In this study, we corroborated that miR-483-5p expression was lessened in type 1 and type 2 diabetic mice kidney tissues and high glucose (HG)-stimulated tubular epithelial cells (TECs), and raised in the exosomes derived from renal tissues in type 1 and type 2 diabetic mice. miR-483-5p restrained the expressions of fibrosis-related genes in vitro and renal interstitial fibrosis in vivo. Mechanistically, miR-483-5p bound both TIMP2 and MAPK1, and TIMP2 and MAPK1 were bound up with the regulation of miR-483-5p on renal TECs under HG conditions. Importantly, HNRNPA1-mediated exosomal sorting transported cellular miR-483-5p out of TECs into the urine. Our results expounded that HNRNPA1-mediated exosomal sorting transported cellular miR-483-5p out of TECs into the urine, thus lessening the restraint of cellular miR-483-5p on MAPK1 and TIMP2 mRNAs, and ultimately boosting extracellular matrix deposition and the progression of DN-induced renal interstitial fibrosis.

Fucoxanthin extracted from Laminaria Japonica inhibits metastasis and enhances the sensitivity of lung cancer to Gefitinib

ETHNOPHARMACOLOGICAL RELEVANCE

Laminaria japonica, a brown seaweed, has been used in Traditional Chinese Medicine (TCM) to treat a variety of diseases including lung cancer.

AIM OF THE STUDY

To demonstrate the effects of Fucoxanthin (FX), a major active component extracted from Laminaria japonica on metastasis and Gefitinib (Gef) sensitivity in human lung cancer cells both in vitro and in vivo.

MATERIALS AND METHODS

Invasion and migration of lung cancer cells were detected using the wound healing assay and transwell assay. Epithelial-to-mesenchymal transition (EMT) factors and PI3K/AKT/NF-κB pathways were analyzed by western blotting. RNA interference (RNAi) technology was used to silence TIMP-2 gene expression in A549 cells. The anti-metastatic effect of FX was evaluated in vivo in an experimental lung metastatic tumor model. On the other hand, cell counting kit-8 assay was used to study the cell viability of human lung cancer PC9 cells and Gef resistant PC9 cells (PC9/G) after Gef, FX or FX combined with Gef treatment. PC9 xenograft model was established to explore the anti-tumor effect of FX or combined with Gef. Immunohistochemistry staining assay and immunofluorescence staining assay were used to reveal the effects of FX on lung cancer cell proliferation and apoptosis.

RESULTS

FX was able to significantly inhibit lung cancer cells migration and invasion in vitro. FX suppressed the expressions of Snail, Twist, Fibronectin, N-cadherin, MMP-2, PI3K, p-AKT and NF-κB, and increased the expression of TIMP-2. Furthermore, knockdown of TIMP-2 attenuated FX-mediated invasion inhibition. Additionally, we demonstrated that FX inhibited lung cancer cells metastasis in vivo. The anti-metastatic effects of FX on lung cancer cells might be attributed to inhibition of EMT and PI3K/AKT/NF-κB pathway. We further demonstrated that the anti-tumor activity of FX was not only limited to the drug sensitive cell lines, but also prominent on lung cancer cells with Gef resistant phenotype. Furthermore, in vivo xenograft assay confirmed that FX inhibited tumor growth and enhanced the sensitivity of lung cancer cells to Gef and this effect may be due to inhibition of tumor cell proliferation and activation of apoptosis.

CONCLUSION

Collectively, our findings suggested that FX suppresses metastasis of lung cancer cells and overcomes EGFR TKIs resistance. Thus, FX is worthy of further investigation as a drug candidate for the treatment of lung cancer.

The Imbalance of MMP-2/TIMP-2 and MMP-9/TIMP-1 Contributes to Collagen Deposition Disorder in Diabetic Non-Injured Skin

The importance of the early diagnosis and treatment of diabetes and its cutaneous complications has become increasingly recognized. When diabetic non-injured skin was stained with Masson's trichrome, its dermal collagen was found to be disordered, its density was variable, and it was dispersed or arranged in vague fascicles. The collagen type I sequencing results of RNA sequencing-based transcriptome analysis of three primary human skin cell types-dermal fibroblasts, dermal microvascular endothelial cells, and epidermal keratinocytes-under high glucose were analyzed. The results showed that both COL1A1 and COL1A2 mRNA expressions were reduced in human dermal fibroblasts (HDFs). The ratio of matrix metalloproteinase (MMP)-2/tissue inhibitors of metalloproteinase (TIMP)-2 and MMP-9/TIMP-1 in HDFs increased when treated with high glucose. By inhibiting MMP-2 and MMP-9 with SB-3CT, collagen deposition disorder of the skin in streptozotocin-induced diabetes mice was alleviated. The imbalance of MMP2/TIMP2 and MMP9/TIMP1 contributes to the non-injured skin disorder of collagen deposition in diabetes, suggesting a possibility for early treatment of diabetes skin complications.

Methylation of MMP2, TIMP2, MMP9 and TIMP1 in abdominal aortic aneurysm

OBJECTIVES

Abdominal aortic aneurysm (AAA) and its complications are among the most serious cardiovascular diseases and its occurrence has risen sharply in recent years. The aim of this pilot study is to explore the relationship between the methylation of matrix metalloproteinases and tissue inhibitors of the metalloproteinases genes' promoter region, and abdominal aortic aneurysm (AAA) through the detection of the methylation status of MMP2, TIMP2, TIMP1, and MMP9 genes in peripheral blood.

METHODS

The study included 43 males with verified AAA (case group) and 34 healthy males (control group). The methylation status of the genes' promoter region was detected by methylation-specific polymerase chain reaction (MS-PCR).

RESULTS

In adominal aortic aneurysm patients, the methylation ratio of MMP2 gene was positive in 9.3 % (4 cases), 2.3 % (1 case) had methylated TIMP2 gene, 7.0 % (3 cases) had methylated TIMP1 gene, while the methylation ratio of MMP9 gene was positive in 93.0 % (40 cases). In the control group, MMP2 gene was found to be methylated in 5.9 % (2 cases), 5.9 % of cases had methylated TIMP2 and TIMP1 genes (2 cases), and MMP9 gene was found to be methylated in 91.2 % (31 cases).

CONCLUSION

In our pilot study, we found no association between DNA methylation of gelatinases and their tissue inhibitors, and the development of an abdominal aortic aneurysm (Tab. 2, Fig. 1, Ref. 27).

Mechanisms underlying dimethyl sulfoxide-induced cellular migration in human normal hepatic cells

Numerous studies have reported that low-dose dimethyl sulfoxide (DMSO, <1.5%, v/v) can interfere with various cellular processes, such as cell proliferation, differentiation, apoptosis, and cycle. By contrast, minimal information is available about the effect of low-dose DMSO on cell migration. Here, we report the effect of DMSO (0.0005%-0.5%, v/v) on cellular migration in human normal hepatic L02 cells. We used the Cell Counting Kit-8 assay to measure cell viability, scratch wound healing assay to observe cellular migration, flow cytometry to analyze cell cycle and death pattern, reverse transcription quantitative polymerase chain reaction to evaluate mRNA expression, and Western blot to detect protein levels. After treatment with 0.0005% (v/v) DMSO, more cells entered S phase arrest, the MMP1/TIMP1 ratio increased, and HSP27 expression was elevated. After treatment with 0.1% (v/v) DMSO, more cells entered G0/G1 phase arrest, the MMP2/TIMP2 ratio increased, the p-p38 and p-Smad3 signaling pathways were activated, and neuropilin-1 expression was elevated. These results showed that cells migrate when their MMP1/TIMP1 and MMP2/TIMP2 ratios are imbalanced. Such migration is modulated by the p38/HSP27 signaling pathway and TGF-β/Smad3 dependent signaling pathway.

ANALYSIS OF POLYMORPHISM OF MATRIX METALLOPROTEINASE-2 (C-1306 → T) AND TISSUE INHIBITORS OF METALLOPROTEINASE-2 (G303 → A) GENES IN PATIENTS WITH ANASTOMOTIC LEAK IN HOLLOW DIGESTIVE ORGANS

To analyze the frequency of polymorphic variants of MMP-2 (C-1306 → T) and TIMP-2 (G303 → A) genes in patients with anastomotic leak in hollow digestive organs. The object of the study comprises 61 patients with anastomotic leak and connective tissue pathology, all treated at the Shalimov National Institute of Surgery and Transplantology during 2016-2019. Laboratory, genetic, histological studies and statistical analysis were performed. As a result of genetic and statistical analysis of the MMP-2 (C-1306 → T) and TIMP-2 (G303 → A) gene polymorphisms, genotype variants have been identified that are associated with the risk of anastomotic leak in hollow digestive organs. Significant differences in the distribution of genotypes in the studied groups were revealed. Analysis of the multiplicative model of inheritance of MMP-2 and TIMP-2 genes showed compliance of genotype distribution with Hardy-Weinberg's law. All models of inheritance were analyzed and the best model with the lowest Akaike Information Criterion, which turned out to be a recessive model, has been determined. Anastomotic leak in hollow digestive organs is 1.36 times more common in carriers of homozygous CC genotype of the MMP-2 gene and twice less common in minor homozygotes of TT (5.9% vs. 10%, p>0.05). It is statistically significant that in the group of patients with anastomotic leak in hollow digestive organs the GG variant of the TIMP-2 gene was detected 1.6 times more often. Carriers of minor homozygotes of AA genotype in the group with suture failure were not detected, while a similar genotype in the control group was found in 10% (p<0.05).

Resveratrol inhibits the tumor migration and invasion by upregulating TET1 and reducing TIMP2/3 methylation in prostate carcinoma cells

BACKGROUND

Recently, resveratrol (Res) has been suggested to suppress the migration and invasion of prostate cancer (PCa). In the present study, we aimed to investigate the effects of Res on genomic DNA methylation, as well as the migration and invasion of PCa cells.

METHODS

The suppression by Res of the growth of PCa cells was verified through a cytotoxicity assay. In addition, the effects of Res on 5-methylcytosine (5mC), 5-hydroxymethylcytosine (5hmC), and ten-eleven translocation 1 (TET1) levels were assessed, and the cell migration and invasion were also determined. The expressions of TET1, tissue inhibitor of metalloproteinases (TIMP) 2, TIMP3, MMP2, and MMP9 were detected through Western blot analysis. Afterward, TET1 was silenced using lentiviral short hairpin RNA to examine the effect of TET1 on the Res-triggered inhibition of migration and invasion of PCa cells.

RESULTS

Our results showed that Res upregulated the 5hmC and TET1 levels and downregulated the 5mC level. Moreover, Res also inhibited the migration and invasion of PCa cells, promoted the demethylation of TIMP2 and TIMP3 to upregulate their expressions, and suppressed the expressions of MMP2 and MMP9. The silencing of TET1 in the presence of Res showed that Res could exert its effect through TET1.

CONCLUSIONS

Our findings indicated that Res inhibited the migration and invasion of PCa cells via the TET1/TIMP2/TIMP3 pathway, which might potentially serve as a target for the treatment of PCa.

Quantitative mapping of binding specificity landscapes for homologous targets by using a high-throughput method

To facilitate investigations of protein-protein interactions (PPIs), we developed a novel platform for quantitative mapping of protein binding specificity landscapes, which combines the multi-target screening of a mutagenesis library into high- and low-affinity populations with sophisticated next-generation sequencing analysis. Importantly, this method generates accurate models to predict affinity and specificity values for any mutation within a protein complex, and requires only a few experimental binding affinity measurements using purified proteins for calibration. We demonstrated the utility of the approach by mapping quantitative landscapes for interactions between the N-terminal domain of the tissue inhibitor of metalloproteinase 2 (N-TIMP2) and three matrix metalloproteinases (MMPs) having homologous structures but different affinities (MMP-1, MMP-3, and MMP-14). The binding landscapes for N-TIMP2/MMP-1 and N-TIMP2/MMP-3 showed the PPIs to be almost fully optimized, with most single mutations giving a loss of affinity. In contrast, the non-optimized PPI for N-TIMP2/MMP-14 was reflected in a wide range of binding affinities, where single mutations exhibited a far more attenuated effect on the PPI. Our new platform reliably and comprehensively identified not only hot- and cold-spot residues, but also specificity-switch mutations that shape target affinity and specificity. Thus, our approach provides a methodology giving an unprecedentedly rich quantitative analysis of the binding specificity landscape, which will broaden the understanding of the mechanisms and evolutionary origins of specific PPIs and facilitate the rational design of specific inhibitors for structurally similar target proteins.

TIMP-2 suppresses tumor growth and metastasis in murine model of triple-negative breast cancer

Metastasis is the primary cause of treatment failures and mortality in most cancers. Triple-negative breast cancer (TNBC) is refractory to treatment and rapidly progresses to disseminated disease. We utilized an orthotopic mouse model that molecularly and phenotypically resembles human TNBC to study the effects of exogenous, daily tissue inhibitor of metalloproteinase-2 (TIMP-2) treatment on tumor growth and metastasis. Our results demonstrated that TIMP-2 treatment maximally suppressed primary tumor growth by ~36-50% and pulmonary metastasis by >92%. Immunostaining assays confirmed disruption of the epithelial to mesenchymal transition (EMT) and promotion of vascular integrity in primary tumor tissues. Immunostaining and RNA sequencing analysis of lung tissue lysates from tumor-bearing mice identified significant changes associated with metastatic colony formation. Specifically, TIMP-2 treatment disrupts periostin localization and critical cell-signaling pathways, including canonical Wnt signaling involved in EMT, as well as PI3K signaling, which modulates proliferative and metastatic behavior through p27 phosphorylation/localization. In conclusion, our study provides evidence in support of a role for TIMP-2 in suppression of triple-negative breast cancer growth and metastasis through modulation of the epithelial to mesenchymal transition, vascular normalization, and signaling pathways associated with metastatic outgrowth. Our findings suggest that TIMP-2, a constituent of the extracellular matrix in normal tissues, may have both direct and systemic antitumor and metastasis suppressor effects, suggesting potential utility in the clinical management of breast cancer progression.

Expression of Matrix Metalloproteinases and Their Inhibitors in Endometrium: High Levels in Endometriotic Lesions

Endometriosis is a condition defined as presence of endometrium outside of the uterine cavity. These endometrial cells are able to attach and invade the peritoneum or ovary, thus forming respectively the deep infiltrating endometriosis (DIE) and the ovarian endometrioma (OMA), the ectopic lesions feature of this pathology. Endometriotic cells display high invasiveness and share some features of malignancy with cancer cells. Indeed, the tissue remodeling underlining lesion formation is achieved by matrix metalloproteinases (MMPs) and their inhibitors. Therefore, these molecules are believed to play a key role in development and pathogenesis of endometriosis. This study investigated the molecular profile of metalloproteinases and their inhibitors in healthy (n = 15) and eutopic endometrium (n = 19) in OMA (n = 10) and DIE (n = 9); moreover, we firstly validated the most reliable housekeeping genes allowing accurate gene expression analysis in these tissues. Gene expression, Western blot, and immunofluorescence analysis of MMP2, MMP3, and MMP10 and their tissue inhibitors TIMP1 and TIMP2 demonstrated that these enzymes are finely tuned in these tissues. In OMA lesions, all the investigated MMPs and their inhibitors were significantly increased, while DIE expressed high levels of MMP3. Finally, in vitro TNFα treatment induced a significant upregulation of MMP3, MMP10, and TIMP2 in both healthy and eutopic endometrial stromal cells. This study, shedding light on MMP and TIMP expression in endometriosis, confirms that these molecules are altered both in eutopic endometrium and endometriotic lesions. Although further studies are needed, these data may help in understanding the molecular mechanisms involved in the extracellular matrix remodeling, a crucial process for the endometrial physiology.

Expression of Metalloproteinases and Type I and III Collagens during Healing of Excisional Skin Wound on the Abdomen and Back in Rats

The study was carried out using a novel rat model developed in our laboratory, namely16 mm diameter circular excisional wounds were generated on the abdomen which resulted in minimal scarring. Restoration of the skin integrity was completed by day 60 after the wounding surgery. By this time, regenerates on the abdomen were stronger than on the back (at, respectively, 58 and 17.4 % of the tensile strength of the intact skin at corresponding location) and the ratio of type I and type III collagens in regenerates on the abdomen reached the level of intact skin at the same location. On days 3 to 14, the ratio of Mmp9/Timp1 expression levels on the abdomen was higher than on the back. On days 20 and 30, the Mmp9/Timp1 ratio on the abdomen was identical to the level of intact skin, whereas the increased MMPs expression levels on the back were maintained until day 30. It has been shown for the first time that according to functional and molecular characteristics, wound healing on the abdomen of an adult rat is more similar to complete regeneration than scarring repair of the back skin.

RECK and TIMP-2 mediate inhibition of MMP-2 and MMP-9 by Annona muricata

Up-regulation of MMP-2 and MMP-9 plays a significant role in promoting cancer progression by degrading the components of the extracellular matrix, thereby enhancing the migration of tumor cells. Although the antiproliferative and apoptotic effect of Annona muricata is well established, its effect on MMP-2 and MMP-9, a major target in several types of cancers, has not been studied. Powdered samples of various parts of A. muricata like fruit, stem, seed, and twig extracted using aqueous methanol showed significant dose-dependent inhibition of MMP-2 and MMP-9 in a highly metastatic fibrosarcoma cell line, HT1080. Additionally, these extracts also up-regulated the expression of several endogenous inhibitors of MMP-2 and MMP-9 like REversion-inducing Cysteine-rich protein with Kazal motifs (RECK) and Tissue Inhibitor of Metalloproteinase- 2 (TIMP-2). Furthermore, primary cells developed from tumor tissues obtained from patients not exposed to chemotherapy, also exhibited similar results. Remarkably, the inhibition of MMP-2 and MMP-9 observed was tumor specific, with the A. muricata fruit extract showing only 2% inhibition in cells obtained from normal tissues, when compared to 60% inhibition observed in cells obtained from tumor samples. The present study elucidates a novel mechanism by which A. muricata extracts selectively exhibit their anti-cancer activity in tumor cells by down-regulating MMP-2 and MMP-9 that are important biomarkers in cancer.

Tissue inhibitor of metalloproteinase-2 (TIMP-2) from red seabream (Pagrus major): Molecular cloning and biochemical characterization of highly expressed recombinant protein

The tissue inhibitor of metalloproteinase-2 (TIMP-2) is originally characterized as an endogenous inhibitor of matrix metalloproteinases (MMPs) to response collagenolysis associated with immune challenge. In this study, the cDNA encoding TIMP-2a gene from red seabream (Pagrus major) muscle was cloned. It was 585 bp encoding a putative protein of 194 amino acids, which comprised all recognized functional domains and showed the high identity to TIMP-2as from other teleost fishes, revealing it belongs to TIMP-2a family. Soluble rTIMP-2a was efficiently expressed using a new constructed pPIC9K-rTIMP-2a vector with high inhibitory activity against to MMP-2 and MMP-9. The recombinant TIMP-2a tagged with 6 histidine residues showed the molecular mass of 23 kDa and isoelectric point of 6.50. Furthermore, the 6 disulfide bonds formed by 12 conserved cysteine residues were identified as functional motifs for its structural stability. In addition, rTIMP-2a possessed the high inhibitory activity against gelatinolytic hydrolysis and degradation of type I collagen which induced by endogenous MMPs in muscle. The results revealed the properties and inhibitory function of rTIMP-2a, which may be a pivotal role in regulation gelatinolytic MMPs metabolization during defense mechanism.

Relationship of common variants in MPP7, TIMP2 and CASP8 genes with the risk of chronic achilles tendinopathy

Previous etiologic studies have indicated that both environmental and genetic factors play important roles in the occurrence and development of chronic Achilles tendinopathy (AT). A recent study documented the results of the largest genome-wide association study for chronic AT to date, indicating that MPP7, TIMP2 and CASP8 may be involved in the occurrence and development of chronic AT. In this study, we aimed to investigate whether MPP7, TIMP2 and CASP8 were associated with susceptibility to chronic AP in a Han Chinese population. A total of 3,680 study subjects comprised 1,288 chronic AT cases, and 2,392 healthy controls were recruited. Forty-four tag SNPs (7 from CASP8, 20 from MPP7, and 17 from TIMP2) were genotyped in the study. Genetic association analyses were performed at both single marker and haplotype levels. Functional consequences of significant SNPs were examined in the RegulomeDB and GTEx databases. Two SNPs, SNP rs1937810 (OR [95%CI] = 1.20 [1.09-1.32], χ2 = 13.50, P = 0.0002) in MPP7 and rs4789932 (OR [95%CI] = 1.24 [1.12-1.37], χ2 = 17.98, P = 2.23 × 10-5) in TIMP2, were significantly associated with chronic AT. Significant eQTL signals for SNP rs4789932 on TIMP2 were identified in human heart and artery tissues. Our results provide further supportive evidence for the association of the TIMP2 and MPP7 genes with chronic AT, which supports important roles for TIMP2 and MPP7 in the etiology of chronic AT, adding to the current understanding of the susceptibility of chronic AT.

All trans retinoic acid modulates TNF-α and CYP2E1 pathways and enhances regression of ethanol-induced fibrosis markers in hepatocytes and HSCs in abstaining rodent model

Context: Our previous studies showed that all trans retinoic acid (ATRA) ameliorates alcohol-induced toxicity. Hence, we evaluated the efficacy of ATRA and abstention in the regression of alcohol-induced hepatotoxicity. Materials and methods: After ethanol administration to rats for 90 days, the regression of alcohol-induced toxicity was studied by supplementing ATRA at a dose of 100 μg/kg body weight for 30 days. It was also compared with animals in abstention. Results and discussion: Ethanol administration enhanced oxidative stress, activated HSCs and increased collagen deposition. All these alterations were reversed to a certain extent by ATRA supplementation. Conclusions: ATRA had better efficacy than just abstention in reducing ethanol-induced toxicity. The mechanism might be downregulation of CYP2E1, leading to reduced oxidative stress in the hepatocytes and thus impeding NFκB activation, cytokine production, activation of HSC and resulting in the reduction of inflammation and remodelling of fibrosis by modulating MMP and TIMP.

Additional evidence supports association of common genetic variants in MMP3 and TIMP2 with increased risk of chronic Achilles tendinopathy susceptibility

OBJECTIVES

To systematically evaluate the effects of matrix metalloproteinase-3 (MMP3) and tissue inhibitor of metalloproteinase-2 (TIMP2) on chronic Achilles tendinopathy (AT) susceptibility. Chronic AT is one of the most prevalent and severe injuries in athletes. Early studies suggested that tendon extracellular matrix (ECM) may be involved in the pathogenesis of chronic AT. MMP3 is an important member of the MMP family and is important to ECM integrity. In addition, tissue inhibitor of metalloproteinase-2 (TIMP2) can indirectly limit the activity of MMP3 activity.

DESIGN

Case-control genetic association study.

METHODS

A total of 1084 chronic AT patients and 2188 controls with Chinese Han ancestry were recruited. Twenty-one SNPs, 4 mapped to MMP3 and 17 mapped to TIMP2, were selected and genotyped. Genetic association analyses and eQTL analyses were performed. In addition, we also examined the potential effects of epistasis using a case-only study design.

RESULTS

Two SNPs, rs679620 (OR=0.82, P=0.0006, MMP3) and rs4789932 (OR=1.2, P=0.0002, TIMP2) were identified to be significantly associated with chronic AT risk. No significant results were obtained from epistasis analyses. SNP rs4789932 was identified to be strongly associated with the gene expression level of TIMP2 in two types of human tissues: atrial appendage (P=0.0003) and tibial artery (P=0.0009).

CONCLUSIONS

We have identified genetic polymorphisms in MMP3 and TIMP2 to be significantly associated with chronic AT risk. Further eQTL analyses indicated that SNP rs4789932 of TIMP2 was related to the gene expression levels of TIMP2. These results suggest important roles for MMP3 and TIMP2 in the pathophysiology of chronic AT.

Role of MMP-2(-1306 C/T) and TIMP-2(-418G/C) Polymorphism in Chinese Han Patients with Acne Vulgaris

Acne is the most common chronic inflammatory skin diseases. Multiple factors, such as hormonal, environmental, immunological, and genetic factors, are thought to be involved in acne. However, genetic studies have yet to elucidate the full mechanism of acne. The aim of this study was to investigate the association of MMP-2 (-1306C/T) and TIMP-2 (-418G/C) polymorphisms with the risk of acne vulgaris in a Chinese Han population. We also analyzed the correlation of clinical parameters and family history in patients with acne vulgaris. This study included 251 acne patients and 121 age- and sex-matched healthy controls. Genomic DNA was extracted from peripheral blood, and genotyping was performed by PCR and DNA sequencing techniques. There is a significant correlation between the MMP-2 (-1306C/T) polymorphism and the acne vulgaris (P<0.001). Although no association was found between the TIMP-2 (-418G/C) polymorphism and the acne vulgaris, patients with the MMP-2 CT/TIMP-2 GG or GC allele are at higher risk of acne vulgaris. There is also a significant difference in the severity of the disease between acne vulgaris patients with and without family history (P<0.001). This study indicated that the MMP-2 (-1306C/T) polymorphism, in combination with the TIMP-2 (-418G/C) polymorphism, contributes to acne vulgaris susceptibility in the Chinese Han population.

Association between tissue inhibitor of metalloproteinase (TIMP) genetic polymorphisms and primary ovarian insufficiency (POI)

BACKGROUND

Until now, an association between tissue inhibitor of metalloproteinase (TIMP) polymorphisms and primary ovarian insufficiency (POI) has not been identified. The aim of our study was to investigate whether the TIMP polymorphisms TIMP1T > C (rs4898), TIMP1G > A (rs6609533), TIMP2G > C (rs8179090), TIMP2G > A (rs2277698), TIMP3G > A (rs135029), and TIMP4T > C (rs3755724), which regulate matrix metalloproteinases (MMPs), confer a risk for primary ovarian insufficiency (POI) in Korean women (further studies would be required to evaluate the associations between TIMP polymorphisms and POI in other populations).

METHODS

We genotyped 137 POI patients and 236 controls for the single nucleotide polymorphism sites using PCR-RFLP analysis. Differences in the frequencies of the TIMP1T > C (rs4898), TIMP1G > A (rs6609533), TIMP2G > C (rs8179090), TIMP2G > A (rs2277698), TIMP3G > A (rs135029), and TIMP4T > C (rs3755724) genotypes between patients and controls were compared, and odds ratios and 95% confidence intervals were determined to measure of the strength of the association between the genotypes and POI.

RESULTS

The TIMP1T > C (rs4898), TIMP1G > A (rs6609533), TIMP2G > C (rs8179090), TIMP2G > A (rs2277698), TIMP3G > A (rs135029), and TIMP4T > C (rs3755724) genotypes, but especially the TIMP2 genotypes, were found more frequently in POI patients than in control subjects. Among the four TIMP loci, the TIMP1T > C (rs4898), TIMP1G > A (rs6609533), TIMP2G > C (rs8179090), TIMP2G > A (rs2277698), TIMP3G > A (rs135029), and TIMP4T > C (rs3755724) haplotypes were identified more frequently in POI patients than in control subjects and conferred susceptibility to POI (P <0.0001).

CONCLUSIONS

The TIMP2G > C (rs8179090) and G > A (rs2277698) alleles were strongly associated with POI. Our data suggest that the minor TIMP2 alleles may increase POI risk in Korean women.

Synergistic effects of TIMP2-418G/C and MMP9-1562C/T variants on the male infertility risk

Matrix metalloproteinases (MMPs) and their inhibitors (TIMPs) involve in the degradation of the extracellular matrix (ECM) that imbalances their activity and may lead to various diseases. The present study aims to evaluate the association between MMP9-1562C/T and TIMP2-418G/C variants and synergistic effects of both variants on male infertility in an Iranian population. We analyzed these polymorphisms in 101 infertile men and 106 fertile men as a control group using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique. Based on the obtained results, no considerable association was observed in MMP9-1562C/T polymorphism frequency between infertile men and controls while frequencies of TIMP2-418G/C variant were significantly different in infertile and control groups (P = 0.028). Men with CC, GC and CC + GC genotypes for TIMP2-418G/C polymorphism had an increased risk of infertility compared to men with GG genotype [OR = 1.85, 95% CI (0.917-3.734, P = 0.086), OR = 1.94, 95% CI (1.098-3.437, P = 0.023) and OR = 2.053 95% CI (1.179-3.577, P = 0.011), respectively]. Also, in the presence of both TIMP2-418C and MMP9-1562T alleles the male infertility risk was significantly increased (P = 0.032). The current study suggests that the variation of TIMP2 gene and its interaction with MMP9 gene might be associated with male infertility. However, to confirm these findings, further studies are required in different ethnicities and with a larger sample size.

Inhibition of microRNA‑939 suppresses the development of human non‑small cell lung cancer via the upregulation of tissue inhibitor of metalloproteinases 2

Numerous microRNAs (miRNA/miRs) have been reported to be associated with the initiation and progression of non‑small cell lung cancer (NSCLC). The aim of the present study was to examine the expression and biological role of miR‑939 in human NSCLC, in vitro. Reverse transcription‑quantitative polymerase chain reaction analysis was used to evaluate the expression of miR‑939 in NSCLC tissues. Cell Counting Kit‑8, 5‑ethynyl‑29‑deoxyuridine and Transwell assays were also used to determine the effects of miR‑939 on tumor cell proliferation and invasion in two human NSCLC cell lines (H1299 and SPCA1). Furthermore, tissue inhibitor of metalloproteinases 2 (TIMP2) was confirmed to be a target of miR‑939 by luciferase reporter assay, western blotting and bioinformatics analysis. Following downregulation of miR‑939 expression, cell proliferative and invasive abilities were significantly suppressed. Collectively, these findings indicated that the knockdown of miR‑939 may inhibit cell proliferation and invasion by regulating the expression of TIMP2 in NSCLC cells. Thus, miR‑939 may be a potential target in the treatment of NSCLC, although this requires further investigation.

Effects of glucocorticoid on the eye development in guinea pigs

Glucocorticoid (GC) has been widely used in clinic. However, the effect of GC on normal and myopic development of eyes is still unknown. In this study, 3-week-old guinea pigs were randomly divided into four groups: No-Lens (control), GC+No-Lens, negative lens-induced myopia (LIM), and GC+LIM. To induce myopia, right eyes were covered with a -10 D lens in GC+LIM and LIM groups. GC+No-Lens and GC+LIM groups received intraperitoneal injections of hydrocortisone (10 mg/kg) once daily for 2 weeks, and then received intragastric hydrocortisone (32.5 mg/kg) every other day for the next 4 weeks, while No-Lens (control) and LIM groups were injected intraperitoneally with saline for 2 weeks, and then given saline by intragastric administertion for the next 4 weeks. Several parameters were assessed: ocular axial length and refractive error, sclera thickness, matrix metalloprotein-2 (MMP-2) and tissue inhibitor metalloprotease-2 (TIMP-2) expressions and localization of the posterior sclera, plasma concentrations of free triiodothyronine (FT3), free thyroxine (FT4), testosterone (T), and oestradiol (E2). Results indicated that: (1) in normal eye development, hydrocortisone could inhibit both the axial elongation and the myopic shift; whereas (2) in LIM eye development, hydrocortisone (a) enhanced the axial elongation, myopic shift and sclera thinning; (b) enhanced the MMP-2 expression and decreased TIMP-2 expression, and (c) elevated the plasma concentration of E2 but decreased the levels of FT3, FT4, and T. In conclusion, glucocorticoid may influence both normal and LIM eye development. The balance of the hormones is fundamental for the eye development.

Silence of Stomatin-Like Protein 2 Represses Migration and Invasion Ability of Human Liver Cancer Cells via Inhibiting the Nuclear Factor Kappa B (NF-κB) Pathway

BACKGROUND Liver cancer is the third leading cause of tumor-related deaths worldwide. Stomatin-like protein 2 (STOML2) is obviously upregulated in various tumors. In this study, we explored the potential roles and mechanisms of si-STOML2 in the migration and invasion of human hepatoma LM3 cells. MATERIAL AND METHODS The expression levels of STOML2 in tissues and cells were separately analyzed with quantitative real-time PCR (qRT-PCR) and Western blotting. The viability, migration, and invasion of cells were assessed by cell counting kit-8 (CCK-8), wound healing, and transwell analysis, respectively. The mRNA and protein levels of various factors were separately measured using qRT-PCR and Western blotting. Correlation analysis between the expression of STOML2 and the clinicopathological features of liver cancer patients was evaluated using the chi-square test. RESULTS Surprisingly, our results showed that STOML2 was upregulated in liver cancer tissue and cells, and this upregulation was linked to tumor size, histologic grade, and metastasis, but was not associated with sex, age, or TNM stage. The knockdown of STOML2 significantly repressed the viability, migration, and invasion of LM3 cells. We also observed that silencing STOML2 markedly downregulated the expression levels of matrix metalloproteinase-2 (MMP-2), MMP-9, metastatic tumor antigen 1 (MTA1), and nuclear factor kappa B (NF-κB), and upregulated levels of E-cadherin, tissue inhibitor of metalloproteinases 2 (TIMP2), and the inhibitor of kappa B (IκB). CONCLUSIONS STOML2 has a vital role in the progression of liver cancer. STOML2 silencing in LM3 cells obviously repressed the abilities of migration and invasion via suppressing the NF-κB pathway.

Involvement of matrix metalloproteinases (MMP-2, -7, -9) and their tissue inhibitors (TIMP-2, -3) in the regression of chicken postovulatory follicles

The study was undertaken to examine mRNA expression and localization of selected matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs), and the activity of MMPs in chicken postovulatory follicles (POFs) during their apoptotic regression. Apoptotic cells and apoptosis-related caspase expression and activity were examined as well. Chickens were sacrificed 2 h and 21 h after ovulation, and five POFs (POF1 to POF5) were isolated from the ovaries. It was found that the number of apoptotic cells (TUNEL-positive) increased along with follicle regression. The relative expression (RQ) of caspase-2, -3, -8 and -9 mRNA increased (P < 0.05) in POF5, while the activity of all examined caspases elevated gradually (approximately 80-150%) reaching the highest level in POF3, and then slowly decreased to the value noted in POF1 (P < 0.05 - P < 0.001). Real-time polymerase chain reaction revealed different expression of MMP-2, -7, -9 and TIMP-2 and -3 on mRNA levels, and activity assay showed the changes in activity of MMP-2 and -9 in the POFs. Regression of the follicles was accompanied predominantly by an increase in the relative expression of MMP-2, and a decrease in TIMP-2 and -3 mRNAs (P < 0.05 - P < 0.001). The activity levels of MMP-2 and -9 showed pronounced changes during the examined period. During follicle regression elevated activity of MMP-2 and -9 was found (P < 0.05 - P < 0.001). Immunohistochemistry demonstrated tissue- and follicle-dependent immunoreactivity of the examined members of the MMP system. In summary, the results showing the apoptotic regression-related changes as well as tissue-dependent differences in the expression of selected MMPs and TIMPs, and activity of MMP-2 and MMP-9, point to the significance that these molecules might participate in the complex orchestration of chicken POF regression.

Macromolecule-Network Electrostatics Controlling Delivery of the Biotherapeutic Cell Modulator TIMP-2

Tissue inhibitor of metalloproteinase 2 (TIMP-2) is an endogenous 22 kDa proteinase inhibitor, demonstrating antitumorigenic, antimetastatic and antiangiogenic activities in vitro and in vivo. Recombinant TIMP-2 is currently undergoing preclinical testing in multiple, murine tumor models. Here we report the development of an inert, injectable peptide hydrogel matrix enabling encapsulation and sustained release of TIMP-2. We studied the TIMP-2 release profile from four β-hairpin peptide gels of varying net electrostatic charge. A negatively charged peptide gel (designated AcVES3) enabling encapsulation of 4 mg/mL of TIMP-2, without effects on rheological properties, facilitated the slow sustained release (0.9%/d) of TIMP-2 over 28 d. Released TIMP-2 is structurally intact and maintains the ability to inhibit MMP activity, as well as suppress lung cancer cell proliferation in vitro. These findings suggest that the AcVES3 hydrogel will be useful as an injectable vehicle for systemic delivery of TIMP-2 in vivo for ongoing preclinical development.

Generation of Expression Plasmids for Angiostatin, Endostatin and Timp-2 for Cancer Gene Therapy

Antiangiogenic therapy may represent a promising approach to cancer treatment. Indeed, the efficacy of endogenous angiogenesis inhibitors, including angiostatin, endostatin and TIMPs, has been demonstrated in many types of solid tumors in animal models. In view of the possible problems associated with long-term administration of inhibitors as recombinant proteins, we propose their delivery as nucleic acids through a gene therapy approach. To this end, eukaryotic expression constructs for murine angiostatin and endostatin as well as human TIMP-2 were generated, and characterized in vitro. All constructs carry the relevant cDNAs under the control of the strong HCMV promoter/enhancer, and cleavable leader signals to allow protein secretion. Expression of the angiogenesis inhibitors was detected by in vitro transcription/translation experiments as well as transfection of 293T cells, followed by Western blotting (WB) or radioimmunoprecipitation analysis of both cell lysates and supernatants (SNs). These constructs might be used for in vivo intramuscular delivery of plasmid DNA and as a set of reagents for the development of retroviral as well as adeno-associated viral (AAV) vectors expressing angiogenesis inhibitors.

Hypoxia Activates Src and Promotes Endocytosis Which Decreases MMP-2 Activity and Aggravates Renal Interstitial Fibrosis

The aggravation of renal interstitial fibrosis in the advanced-stage of chronic kidney disease is related to decreased matrix metalloproteinase-2 (MMP-2) activity, which is induced by hypoxia in the kidney; however, the specific mechanism remains unclear. We previously demonstrated that inhibition of Caveolin-1, a key gene involved in endocytosis, increased MMP-2 activity in hypoxic HK-2 cells. It has been reported that activated Src (phospho-Src Tyr416) is a key molecule in multiple fibrotic pathways. However, whether Src functions on the regulation of Caveolin-1 and MMP-2 activity in hypoxic HK-2 cells remains poorly understood. To explore the underlying mechanism, a rat model of renal interstitial fibrosis was established, then we observed obvious hypoxia in fibrotic kidney tissue and the protein levels of phospho-Src and Caveolin-1 increased, while MMP-2 activity decreased. Next, we treated HK-2 cells with the phospho-Src inhibitor PP1. Compared with normal cells grown in hypoxia, in cells treated with PP1, the protein levels of phospho-Src and Caveolin-1 decreased, as did the protein levels of the MMP-2-activity-regulated molecules RECK (reversion-inducing-cysteine-rich protein with kazal motifs) and TIMP-2 (tissue inhibitor of metalloproteinase-2), while the protein level of MT1-MMP (membrane type 1-matrix metalloproteinase) increased and MMP-2 activity was enhanced. Therefore, hypoxia promotes the phosphorylation of Src and phospho-Src can enhance the endocytosis of HK-2 cells, which leads to decreased MMP-2 activity and aggravates renal interstitial fibrosis.

LncRNA GAS5 Represses Osteosarcoma Cells Growth and Metastasis via Sponging MiR-203a

BACKGROUND/AIMS

LncRNA GAS5, a growth suppressor, has been reported to exert anti-tumor actions in various cancers, whereas the exact mechanism underling the anti-tumor action is still unclear. This study was aimed to investigate the effect of lncRNA GAS5 on osteosarcoma and tried to decode the underling mechanisms.

METHODS

Expressions of lncRNA GAS5 in MG-63 cells were silenced by shRNA transfection, while were overexpressed by vector transfection. Cell viability, migration, invasion and apoptosis were respectively assessed by MTT, Transwell assay and flow cytometry. Regulations between lncRNA GAS5 and miR-203a, as well as between miR-203a and TIMP2 were detected by qPCR, western blot and dual luciferase activity assay.

RESULTS

LncRNA GAS5 was down-regulated in MG-63 and OS-732 cells compared to hFOB1.19 cells. Silence of lncRNA GAS5 significantly promoted MG-63 cells viability, migration and invasion, and up-regulated Cyclin D1, Cyclin B1, CDK1 and CDK4 expressions. miR-203a was negatively regulated by lncRNA GAS5. The promoting activities of lncRNA GAS5 silence on MG-63 cells growth and metastasis were reversed by miR-203a suppression. TIMP2 was a target of miR-203a and the anti-growth and anti-metastasis actions of miR-203a suppression were reversed by TIMP2 silence. Further, lncRNA GAS5 silence, miR-203a overexpression, and TIMP2 silence could activate PI3K/AKT/GSK3β signaling while block NF-κB signaling.

CONCLUSION

LncRNA GAS5 might be a tumor suppressor in osteosarcoma via sponging miR-203a, sequestering miR-203a away from TIMP2.