OBJECTIVE: The up-regulation of matrix metalloproteinase-9 (MMP-9) expression is a characteristic feature observed across various malignancies, including nasopharyngeal carcinoma (NPC). Nevertheless, the influence of MMP-9 genotype in the context of NPC remains underexplored. This study examined the implications of MMP-9 promoter rs3918242 genotypes on the susceptibility to NPC in Taiwan.
METHODS: In a cohort comprising 208 NPC cases and 416 healthy controls, genotyping of MMP-9 rs3918242 was conducted utilizing polymerase chain reaction-restriction fragment length polymorphism methodology.
RESULTS: Individuals harbouring the variant CT or TT genotype of MMP-9 rs3918242 did not demonstrate a discernible alteration in NPC risk when compared to wild-type CC carriers [odds ratio (OR)=0.83 and 0.79, with 95% confidence intervals (95%CI)=0.56-1.24 and 0.27-2.29; p=0.4205 and 0.8675, respectively]. Moreover, the presence of the variant T allele did not confer a modified risk of NPC (OR=0.84, 95%CI=0.60-1.19, p=0.3761). Intriguingly, a protective effect associated with the MMP-9 rs3918242 CT genotype against NPC risk was discerned among individuals abstaining from betel quid chewing behaviour (OR=0.51, 95%CI=0.30-0.87, p=0.0166). Notably, no significant association was established between the MMP-9 rs3918242 CT or TT genotype and NPC risk among individuals with or without smoking or alcohol consumption habits.
CONCLUSIONS: Presence of the variant CT or TT genotype at MMP-9 rs3918242 did not appear to substantially contribute to an elevated risk of NPC. Notably, a protective effect against NPC risk was observed in individuals carrying the CT genotype, particularly in those abstaining from betel quid chewing.

Early metastasis of pancreatic cancer (PaC) is a major cause of its high mortality rate. Previous studies have shown that AHNAK2 is involved in the progression of some tumors and is predicted to be an independent prognostic factor for PaC; however, the specific mechanisms through which AHNAK2 regulates PaC remain unclear. In this study, we examined the role of AHNAK2 in PaC and its potential molecular mechanisms. AHNAK2 mRNA and protein expression in PaC tissues and cells were measured using qRT-PCR and western blot analysis. After AHNAK2 knockdown using small interfering RNA, PaC cells were subjected to CCK-8 scratch, and Transwell assays to assess cell proliferation, migration, and invasion, respectively. Furthermore, the validation of the mechanistic pathway was achieved by western blot analysis. AHNAK2 mRNA and protein levels were up-regulated in PaC and silencing AHNAK2 significantly inhibited the proliferation, migration, and invasion of PaC cells. Mechanistically, AHNAK2 knockdown decreased the expression of phosphorylated p65, phosphorylated IκBα, and matrix metalloproteinase-9 (MMP-9), suggesting that activation of the NF-κB/MMP-9 signaling pathway was inhibited. Importantly, activation of NF-κB reversed the effects of AHNAK2 knockdown. Our findings indicate that AHNAK2 promotes PaC progression through the NF-kB/MMP-9 pathway and provides a theoretical basis for targeting AHNAK2 for the treatment of PaC.

Moyamoya disease (MMD) is a chronic, progressive cerebrovascular occlusive disease. Ring finger protein 213 (RNF213) is a susceptibility gene of MMD. Previous studies have shown that the expression levels of angiogenic factors increase in MMD patients, but the relationship between the susceptibility gene RNF213 and these angiogenic mediators is still unclear. The aim of the present study was to investigate the pathogenesis of MMD by examining the effect of RNF213 gene knockdown on the expression of matrix metalloproteinase-9 (MMP-9) and basic fibroblast growth factor (bFGF) in rat bone marrow-derived mesenchymal stem cells (rBMSCs). Firstly, 40 patients with MMD and 40 age-matched normal individuals (as the control group) were enrolled in the present study to detect the levels of MMP-9 and bFGF in serum by ELISA. Secondly, Sprague-Dawley male rat BMSCs were isolated and cultured using the whole bone marrow adhesion method, and subsequent phenotypic analysis was performed by flow cytometry. Alizarin red and oil red O staining methods were used to identify osteogenic and adipogenic differentiation, respectively. Finally, third generation rBMSCs were transfected with lentivirus recombinant plasmid to knockout expression of the RNF213 gene. After successful transfection was confirmed by reverse transcription-quantitative PCR and fluorescence imaging, the expression levels of bFGF and MMP-9 mRNA in rBMSCs and the levels of bFGF and MMP-9 protein in the supernatant of the culture medium were detected on the 7th and 14th days after transfection. There was no significant difference in the relative expression level of bFGF among the three groups on the 7th day. For the relative expression level of MMP-9, there were significant differences on the 7th day and 14th day. In addition, there was no statistically significant difference in the expression of bFGF in the supernatant of the RNF213 shRNA group culture medium, while there was a significant difference in the expression level of MMP-9. The knockdown of the RNF213 gene affects the expression of bFGF and MMP-9. However, further studies are needed to determine how they participate in the pathogenesis of MMD. The findings of the present study provide a theoretical basis for clarifying the pathogenesis and clinical treatment of MMD.

OBJECTIVE: To investigate the effect of early vascular embolization for intracranial aneurysms and the effect of matrix metalloproteinase-9 (MMP-9) and nuclear factor-kappa B (NF-κB) on nerve function.
METHODS: This is a retrospective analysis study. A total of 90 patients with intracranial aneurysms admitted to our hospital from January 2017 to December 2021 were selected as research subjects. The patients were divided into a control group (n=47) and an observation group (n=43) according to different embolization timing. Both groups were treated with vascular embolization, the observation group received vascular embolization within 72 h after onset, while the control group received vascular embolization after 72 h. In addition, both groups were given clopidogrel bisulfate tablets and enteric-coated aspirin tablets from the day after operation for 3 months. The embolization at 3 months after operation, the occurrence of complications, the daily activities and neurological function before and 3 months after operation, serum levels of MMP-9 and NF-κB, the protein expression of MMP-9 and NF-κB, and the prognosis at 3 months after operation were compared between the two groups.
RESULTS: The complete embolization rate (90.70%) in observation group was higher than that of the control group (72.34%) at 3 months after operation (P<0.05). The postoperative complications in the observation group (9.30%) were lower than those of the control group (27.66%) (P<0.05). The improvement in Modified Barthel index score, as well as serum levels of MMP-9 and NF-κB were better in the observation group than those of the control group 3 months after operation (P<0.05). The prognosis of patients in the observation group was better than those of the control group 3 months after operation (P<0.05).
CONCLUSIONS: Early vascular embolization is an effective approach for intracranial aneurysm. It helps improve patients\' neurological function, and reduce their serum and protein levels of both MMP-9 and NF-κB, thereby leading to favorable prognosis.

UNASSIGNED: To analyzes the changes in serum levels of matrix metalloproteinase-9 (MMP-9), neuroenolase (NSE), myeloperoxidase (MPO) and prognostic factors in patients with intracranial aneurysm (IA) undergoing interventional embolization at different treatment times.
UNASSIGNED: A retrospective analysis was made of 200 IA patients admitted to our department from January 2018 to June 2021 was performed. All patients underwent interventional embolization. According to the timing of surgery, the patients were divided into an early group (n=120, onset to surgery ≤72 h) and a delayed group (n=80, onset to surgery >72 h). The effect of embolization, complications and neurological deficit scale (NDS) scores were compared between the two groups. Serum MMP-9, NSE and MPO levels were compared before and after surgery, and the prognosis of all patients within 2 years after surgery was assessed by the Glasgow outcome scale (GOS) and divided accordingly into the good prognosis group (n=147) and the poor prognosis group (n=53) accordingly, and the prognostic factors influencing the patients were analyzed univariately and multifactorially.
UNASSIGNED: Cilj je bio da se analiziraju promene u serumskim nivoima matriks metaloproteinaze-9 (MMP-9), neuroenolaze (NSE), mijeloperoksidaze (MPO) i prognostičkih faktora kod pacijenata sa intrakranijalnom aneurizmom (IA) koji su podvrgnuti interventnoj embolizaciji u različitim vremenima lečenja.
UNASSIGNED: Urađena je retrospektivna analiza 200 pacijenata sa IA koji su primljeni na naše odeljenje od januara 2018. do juna 2021. godine. Svi pacijenti su podvrgnuti interventnoj embolizaciji. Prema vremenu operacije, pacijenti su podeljeni u ranu grupu (n=120, početak operacije ≤72 h) i odloženu grupu (n=80, početak operacije >72 h). Efekat embolizacije, komplikacije i rezultati skale neurološkog deficita (NDS) su upoređeni između dve grupe. Nivoi MMP-9, NSE i MPO u serumu su upoređeni pre i posle operacije, a prognoza svih pacijenata u roku od 2 godine nakon operacije procenjena je Glasgov skalom ishoda (GOS) i prema tome podeljena u grupu sa dobrom prognozom (n=147) i grupa sa lošom prognozom (n=53) shodno tome, a prognostički faktori koji utiču na pacijente analizirani su univarijantno i multifaktorski.
UNASSIGNED: Nakon operacije, stopa potpune embolije bila je veća u ranoj grupi nego u odloženoj grupi (P<0,05). Nakon operacije, nije bilo statističke značajnosti u poređenju pojedinačnih stopa komplikacija u obe grupe (P>0,05). U 3d, 1 mesec i 6 meseci nakon operacije, rezultati NDS pacijenata u obe grupe su bili niži od onih pre operacije, a poređenje NDS rezultata pacijenata u obe grupe u različitim vremenskim tačkama je bilo statistički značajno ( P<0,05). Posle operacije, nivoi MMP-9, NSE i MPO u serumu su bili niži u obe grupe nego pre operacije, a bili su niži u ranoj grupi nego u odloženoj grupi (P<0,05). Rezultati GOS-a su pokazali da je u roku od 2 godine nakon operacije bilo 97 i 23 slučaja sa dobrom i lošom prognozom u ranoj grupi i 54 i 26 slučajeva sa dobrom i lošom prognozom u odloženoj grupi, respektivno, a stopa dobre prognoze u ranoj grupi grupa je bila veća od one u odloženoj grupi (P<0,05). Multifaktorska analiza je pokazala da su odložena operacija, aneurizma u zadnjoj cirkulaciji, širina vrata aneurizme >4,5 mm, stepen III-IV po Fisheru, stepen III-IV Hunt-Hess i hipertenzija nezavisni faktori rizika za lošu prognozu nakon interventne embolizacije IA (P <0,05).
UNASSIGNED: Rana interventna embolizacija kod pacijenata sa IA može poboljšati njihovu potpunu stopu embolizacije i smanjiti nivoe MMP-9, NSE i MPO u serumu; odložena operacija, aneurizma u zadnjoj cirkulaciji, širina vrata aneurizme >4,5 mm, Fisher stepen III-IV, Hunt-Hess stepen III-IV i hipertenzija su snažno povezani sa lošom prognozom nakon interventne embolizacije kod pacijenata sa IA.

The glymphatic system plays a crucial role in maintaining optimal central nervous system (CNS) function by facilitating the removal of metabolic wastes. Aquaporin-4 (AQP4) protein, predominantly located on astrocyte end-feet, is a key pathway for metabolic waste excretion. β-Dystroglycan (β-DG) can anchor AQP4 protein to the end-feet membrane of astrocytes and can be cleaved by matrix metalloproteinase (MMP)-9 protein. Studies have demonstrated that hyperglycemia upregulates MMP-9 expression in the nervous system, leading to neuropathic pain. Ginkgolide B (GB) exerts an inhibitory effect on the MMP-9 protein. In this study, we investigated whether inhibition of MMP-9-mediated β-DG cleavage by GB is involved in the regulation of AQP4 polarity within the glymphatic system in painful diabetic neuropathy (PDN) and exerts neuroprotective effects. The PDN model was established by injecting streptozotocin (STZ). Functional changes in the glymphatic system were observed using magnetic resonance imaging (MRI). The paw withdrawal threshold (PWT) was measured to assess mechanical allodynia. The protein expressions of MMP-9, β-DG, and AQP4 were detected by Western blotting and immunofluorescence. Our findings revealed significant decreases in the efficiency of contrast agent clearance within the spinal glymphatic system of the rats, accompanied by decreased PWT, increased MMP-9 protein expression, decreased β-DG protein expression, and loss of AQP4 polarity. Notably, GB treatment demonstrated the capacity to ameliorate spinal cord glymphatic function by modulating AQP4 polarity through MMP-9 inhibition, offering a promising therapeutic avenue for PDN.

BACKGROUND: Reversion-inducing cysteine-rich protein with Kazal motifs (RECK), a recently discovered inhibitor of matrix metalloproteinase (MMP). There is a large number of chronic obstructive pulmonary disease (COPD) patients worldwide; however, the role of RECK on COPD has not been studied. This study explored the expression of RECK in COPD patients and its effect on neutrophil function to provide a new scientific basis for the prevention and treatment of COPD.
METHODS: Fifty patients with acute exacerbation of COPD and fifty healthy controls were enrolled in the study. RECK was detected in lung tissue, sputum, and plasma of subjects as well as in BEAS-2B cells stimulated with cigarette smoke extract (CSE) by immunohistochemistry, ELISA, and qRT-PCR. Meanwhile, lung function (FEV1%pred) and inflammatory cytokines (IL-6 and IL-8) were examined, and correlation analysis was performed with RECK expression. The effect of RECK on proliferation, apoptosis, migration, and inflammatory cytokines and its potential mechanism was further quantified by neutrophil stimulated with recombinant human RECK protein (rhRECK) combined with CSE using CCK8, flow cytometry, Transwell assay, qRT-PCR, ELISA, and Western analysis.
RESULTS: RECK was mainly expressed on airway epithelial cells in normal lung tissue and was significantly diminished in COPD patients. The levels of RECK in sputum and plasma were also significantly decreased in COPD patients. Pearson correlation analysis showed that RECK level in plasma was positively correlated with FEV1%pred (r = 0.458, p < 0.001) and negatively correlated with IL-6 and IL-8 (r = -0.386, -0.437; p = 0.006, 0.002) in COPD patients. The expression of RECK was decreased in BEAS-2B stimulated with CSE. The migration, inflammation, and MMP-9 expression of neutrophils were promoted by CSE, while inhibited by rhRECK.
CONCLUSIONS: RECK is low expressed in COPD patients and negatively correlated with inflammation. It may inhibit the inflammation and migration of neutrophils by downregulating MMP-9.

Studies have found that matrix metalloproteinase-9 (MMP-9) plays a significant role in cancer cell invasion, metastasis, and tumor growth. But it is a challenge to go for highly sensitive and selective detection and targeting of MMP-9 due to the similar structure and function of the MMP proteins family. Herein, a novel surface-enhanced Raman scattering (SERS) sensing strategy was developed based on the aptamer-induced SERS \"hot spot\" formation for the extremely sensitive and selective determination of MMP-9. To develop the nanosensor, one group of gold nanospheres was modified with MMP-9 aptamer and its complementary strand DNA1, while DNA2 (complementary to DNA1) and the probe molecule 5,5\'-dithiobis-(2-nitrobenzoic acid) (DTNB) were grafted on the surface of the other group of gold nanospheres. In the absence of MMP-9, DTNB located on the 13-nm gold nanospheres has only generated a very weak SERS signal. However, when MMP-9 is present, the aptamer preferentially binds to the MMP-9 to construct MMP-9-aptamer complex. The bare DNA1 can recognize and bind to DNA2, which causes them to move in close proximity and create a SERS hot spot effect. Due to this action, the SERS signal of DTNB located at the nanoparticle gap is greatly enhanced, achieving highly sensitive detection of MMP-9. Since the hot spot effect is caused by the aptamer that specifically recognizes MMP-9, the approach exhibits excellent selectivity for MMP-9 detection. Based on the benefits of both high sensitivity and excellent selectivity, this method was used to distinguish the difference in MMP-9 levels between normal and cancer cells as well as the expression of MMP-9 from cancer cells with different degrees of metastasis. In addition, this strategy can accurately reflect the dynamic changes in intracellular MMP-9 levels, stimulated by the MMP-9 activator and inhibitor. This strategy is expected to be transformed into a new technique for diagnosis of specific cancers related to MMP-9 and assessing the extent of cancer occurrence, development and metastasis.

Fibrosis is a process of tissue repair that results in the slow creation of scar tissue to replace healthy tissue and can affect any tissue or organ. Its primary feature is the massive deposition of extracellular matrix (mainly collagen), eventually leading to tissue dysfunction and organ failure. The progression of fibrotic diseases has put a significant strain on global health and the economy, and as a result, there is an urgent need to find some new therapies. Previous studies have identified that inflammation, oxidative stress, some cytokines, and remodeling play a crucial role in fibrotic diseases and are essential avenues for treating fibrotic diseases. Among them, matrix metalloproteinases (MMPs) are considered the main targets for the treatment of fibrotic diseases since they are the primary driver involved in ECM degradation, and tissue inhibitors of metalloproteinases (TIMPs) are natural endogenous inhibitors of MMPs. Through previous studies, we found that MMP-9 is an essential target for treating fibrotic diseases. However, it is worth noting that MMP-9 plays a bidirectional regulatory role in different fibrotic diseases or different stages of the same fibrotic disease. Previously identified MMP-9 inhibitors, such as pirfenidone and nintedanib, suffer from some rather pronounced side effects, and therefore, there is an urgent need to investigate new drugs. In this review, we explore the mechanism of action and signaling pathways of MMP-9 in different tissues and organs, hoping to provide some ideas for developing safer and more effective biologics.

Accumulating evidence has indicated that oxidative stress (OS) and matrix metalloproteinase-9 (MMP-9) may contribute to the mechanism of schizophrenia. In the present study, we aimed to evaluate the associations of OS parameters and MMP-9 levels with psychopathological symptoms in male chronic schizophrenia patients.
This study was an observational, cross-sectional, retrospective case-control study. Plasma hydrogen peroxide (H2O2), malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), serum matrix metalloproteinase-9 (MMP-9), and tissue inhibitors of metalloproteinases-1 (TIMP-1) levels were assayed in 80 male patients with chronic schizophrenia and 80 matched healthy controls. Schizophrenia symptoms were assessed by the Positive and Negative Syndrome Scale (PANSS). Multivariate regression was used to analyze relationships between OS parameters and MMP-9, and clinical symptoms.
Our results demonstrated that levels of antioxidant enzymes, SOD, GSH-Px, H2O2, and MDA were significantly decreased, whereas CAT and MMP-9 levels were increased in patients with schizophrenia, when compared with healthy controls (all P < 0.05). In schizophrenia patients, correlation analyses showed that H2O2 levels were significantly and positively correlated with PANSS positive scores, CAT and MDA levels were significant negatively correlated with PANSS negative scores and PANSS total scores, and MDA levels were significantly positively correlated with MMP-9 levels (all P < 0.05). However, we did not find that MMP-9 played an interaction role between OS parameters and PANSS total scores and subscales scores (all P > 0.05).
Our results showed that alterations of plasma OS parameters in male patients with chronic schizophrenia were associated with psychopathology and MMP-9, suggesting that OS and neuroinflammation may play important role in the mechanism of schizophrenia.