Leucine-rich Α-2-glycoprotein 1 Research Articles

The importance of leucine-rich α-2 glycoprotein-1 in acute calculus cholecystitis.

The aim of this prospective, single-center cohort study was to analyze serum leucine-rich α-2-glycoprotein-1 (LRG1) expression in patients with acute cholecystitis (AC) and to investigate its variation depending on symptom duration. Participants were divided into patients with AC and a healthy control group. At the time of diagnosis, blood samples were collected, and symptom onset times were questioned. Collected serum LRG1 levels were measured. 30 patients and 30 healthy volunteers were included in the study. LRG1 (p=0.008), white blood cells (WBC) (p<0.001), platelet (p=0.003), neutrophil (p<0.001), lymphocyte (p=0.001), and CRP (p=0.014) were significantly different in AC patients vs. the control group. When the correlations of serum laboratory values with the time of onset of symptoms were compared, LRG1 (p<0.001) was significantly correlated, while no significant correlation was observed in C-reactive protein (CRP) (p=0.572), WBC (p=0.155), and neutrophil (p=0.155). LRG1 expression increases after 24 hours in AC patients. Due to its correlation with symptom duration, we believe it can be helpful for timing cholecystectomy.

Quantitative Proteomic Analysis Reveals Functional Alterations of the Peripheral Immune System in Colorectal Cancer

Colorectal cancer (CRC) is characterized by high morbidity, high mortality, and limited response to immunotherapies. The peripheral immune system is an important component of tumor immunity, and enhancements of peripheral immunity help to suppress tumor progression. However, the functional alterations of the peripheral immune system in CRC are unclear. Here, we used mass spectrometry-based quantitative proteomics to establish a protein expression atlas for the peripheral immune system in CRC, including plasma and five types of immune cells (CD4+ T cells, CD8+ T cells, monocytes, natural killer cells, and B cells). Synthesizing the results of the multidimensional analysis, we observed an enhanced inflammatory phenotype in CRC, including elevated expression of plasma inflammatory proteins, activation of the inflammatory pathway in monocytes, and increased inflammation-related ligand-receptor interactions. Notably, we observed tumor effects on peripheral T cells, including altered cell subpopulation ratios and suppression of cell function. Suppression of CD4+ T cell function is mainly mediated by high expression levels of protein tyrosine phosphatases. Among them, the expression of protein tyrosine phosphatase receptor type J (PTPRJ) gradually increased with CRC progression; knockdown of PTPRJ in vitro could promote T cell activation, thereby enhancing peripheral immunity. We also found that the combination of leucine-rich α-2 glycoprotein 1 (LRG1) and apolipoprotein A4 (APOA4) had the best predictive ability for colorectal cancer and has the potential to be a biomarker. Overall, this study provides a comprehensive understanding of the peripheral immune system in CRC. It also offers insights regarding the potential clinical utilities of these peripheral immune characteristics as diagnostic indicators and therapeutic targets.

The disruptive role of LRG1 on the vasculature and perivascular microenvironment.

The establishment of new blood vessels, and their subsequent stabilization, is a critical process that facilitates tissue growth and organ development. Once established, vessels need to diversify to meet the specific needs of the local tissue and to maintain homeostasis. These processes are tightly regulated and fundamental to normal vessel and tissue function. The mechanisms that orchestrate angiogenesis and vessel maturation have been widely studied, with signaling crosstalk between endothelium and perivascular cells being identified as an essential component. In disease, however, new vessels develop abnormally, and existing vessels lose their specialization and function, which invariably contributes to disease progression. Despite considerable research into the vasculopathic mechanisms in disease, our knowledge remains incomplete. Accordingly, the identification of angiocrine and angiopathic molecules secreted by cells within the vascular microenvironment, and their effect on vessel behaviour, remains a major research objective. Over the last decade the secreted glycoprotein leucine-rich α-2 glycoprotein 1 (LRG1), has emerged as a significant vasculopathic molecule, stimulating defective angiogenesis, and destabilizing the existing vasculature mainly, but not uniquely, by altering both canonical and non-canonical TGF-β signaling in a highly cell and context dependent manner. Whilst LRG1 does not possess any overt homeostatic role in vessel development and maintenance, growing evidence provides a compelling case for LRG1 playing a pleiotropic role in disrupting the vasculature in many disease settings. Thus, LRG1 has now been reported to damage vessels in various disorders including cancer, diabetes, chronic kidney disease, ocular disease, and lung disease and the signaling processes that drive this dysfunction are being defined. Moreover, therapeutic targeting of LRG1 has been widely proposed to re-establish a quiescent endothelium and normalized vasculature. In this review, we consider the current status of our understanding of the role of LRG1 in vascular pathology, and its potential as a therapeutic target.

Plasma leucine-rich α-2 glycoprotein 1 in ST-elevation myocardial infarction: vertical variation, correlation with T helper 17/regulatory T ratio, and predictive value on major adverse cardiovascular events.

Leucine-rich α-2 glycoprotein 1 (LRG1) promotes inflammation and myocardial injury, but its clinical role in ST-elevation myocardial infarction (STEMI) is rarely disclosed. Herein, this prospective study aimed to explore the value of plasma LRG1 at different time points to predict major adverse cardiovascular event (MACE) risk in patients with STEMI. In total, 209 patients with STEMI were enrolled for determining plasma LRG1 at admission and on day (D)1/D7/D30 after admission via enzyme-linked immunosorbent assay, as well as for determination of peripheral blood T helper 17 (Th17) cells and regulatory T (Treg) cells by flow cytometry. In addition, plasma LRG1 was obtained from 30 healthy controls at enrollment. LRG1 was increased in patients with STEMI at admission compared with healthy controls (P < 0.001). In patients with STEMI, LRG1 varied at different time points (P < 0.001), which elevated from admission to D1, and gradually declined thereafter. LRG1 at admission was positively associated with Th17 cells (P = 0.001) and Th17/Treg ratio (P = 0.014). LRG1 at admission (P = 0.013), D1 (P = 0.034), D7 (P = 0.001), and D30 (P = 0.010) were increased in patients with MACE compared with those without. LRG1 at D7 exhibited good ability to estimate MACE risk (area under curve = 0.750, 95% confidence interval = 0.641-0.858). LRG1 at admission > 60 μg/ml (P = 0.031) and D7 > 60 μg/ml (P = 0.018) were linked with increased accumulating MACE. Importantly, LRG1 at D7 > 60 μg/ml was independently correlated with increased MACE risk (hazard ratio = 5.216, P = 0.033). Plasma LRG1 increases from admission to D1 and gradually declines until D30, which positively links with Th17 cells and MACE risk in patients with STEMI.

Leucine-rich alpha-2-glycoprotein 1 affects bone destruction via IL-6 in mouse periodontitis model.

To investigate the production of leucine-rich α-2-glycoprotein-1 (LRG1) in periodontitis patients and its effectiveness as a new diagnostic marker for periodontitis. In vitro experiments were conducted to analyze LRG1 mRNA expression in human gingival epithelial cells and fibroblasts via quantitative real-time PCR. Invivo experiments were conducted to analyze LRG1 localization in periodontitis patients. The correlation between the serum LRG1 levels and alveolar bone resorption in the mouse periodontitis model was also investigated. A positive correlation existed between the periodontal inflamed surface area and serum LRG1 levels (Spearman's rank correlation coefficient: 0.60). LRG1 mRNA expression in human gingival epithelial cells and fibroblasts was upregulated by Porphyromonas gingivalis stimulation or tumor necrosis factor-α stimulation. Interleukin-6 in human gingival epithelial cells and fibroblasts induced the production of LRG1 and transforming growth factor-β. LRG1 levels in the periodontal tissue and serum in the periodontitis model were higher than those in control mice. LRG1 local administration resulted in alveolar bone resorption, whereas the administration of interleukin-6R antibody inhibited bone resorption. LRG1 levels in serum and periodontal tissue are upregulated in periodontitis and are implicated in periodontal tissue destruction through interleukin-6 production.

High serum levels of leucine-rich α-2 glycoprotein 1 (LRG-1) are associated with poor survival in patients with early breast cancer.

Leucine-rich α-2 glycoprotein 1 (LRG-1) is a secreted glycoprotein that is mainly produced in the liver. Elevated levels of LRG-1 are found in a multitude of pathological conditions including eye diseases, diabetes, infections, autoimmune diseases, and cancer. In patients with early breast cancer (BC), high intratumoral LRG-1 protein expression levels are associated with reduced survival. In this study, we assessed serum levels of LRG-1 in patients with early BC and investigated its correlation with the presence of disseminated tumor cells (DTCs) in the bone marrow and survival outcomes. Serum LRG-1 levels of 509 BC patients were determined using ELISA and DTCs were assessed by immunocytochemistry using the pan-cytokeratin antibody A45-B/B3. We stratified LRG-1 levels according to selected clinical parameters. Using the log-rank (Mantel-Cox) test and multivariate Cox regression analysis, Kaplan-Meier survival curves and prognostic relevance were assessed. Mean serum levels of LRG-1 were 29.70 ± 8.67µg/ml. Age was positively correlated with LRG-1 expression (r = 0.19; p < 0.0001) and significantly higher LRG-1 levels were found in patients over 60years compared to younger ones (30.49 ± 8.63µg/ml vs. 28.85 ± 8.63µg/ml; p = 0.011) and in postmenopausal patients compared to premenopausal patients (30.15 ± 8.34µg/ml vs. 26.936.94µg/ml; p = 0.002). Patients with no DTCs showed significantly elevated LRG-1 levels compared to the DTC-positive group (30.51 ± 8.69µg/ml vs. 28.51 ± 8.54µg/ml; p = 0.004). Overall and BC-specific survival was significantly lower in patients with high serum LRG-1 levels (above a cut-off of 33.63µg/ml) compared to patients with lower LRG-1 levels during a mean follow-up of 8.5years (24.8% vs. 11.1% BC-specific death; p = 0.0003; odds ratio 2.63, 95%CI: 1.56-4.36). Multivariate analyses revealed that LRG-1 is an independent prognostic marker for BC-specific survival (p = 0.001; hazard ratio 2.61). This study highlights the potential of LRG-1 as an independent prognostic biomarker in patients with early BC.

Proteomic Biomarkers for the Prediction of Transition to Psychosis in Individuals at Clinical High Risk: A Multi-cohort Model Development Study.

Psychosis risk prediction is one of the leading challenges in psychiatry. Previous investigations have suggested that plasma proteomic data may be useful in accurately predicting transition to psychosis in individuals at clinical high risk (CHR). We hypothesized that an a priori-specified proteomic prediction model would have strong predictive accuracy for psychosis risk and aimed to replicate longitudinal associations between plasma proteins and transition to psychosis. This study used plasma samples from participants in 3 CHR cohorts: the North American Prodrome Longitudinal Studies 2 and 3, and the NEURAPRO randomized control trial (total n = 754). Plasma proteomic data were quantified using mass spectrometry. The primary outcome was transition to psychosis over the study follow-up period. Logistic regression models were internally validated, and optimism-corrected performance metrics derived with a bootstrap procedure. In the overall sample of CHR participants (age: 18.5, SD: 3.9; 51.9% male), 20.4% (n = 154) developed psychosis within 4.4 years. The a priori-specified model showed poor risk-prediction accuracy for the development of psychosis (C-statistic: 0.51 [95% CI: 0.50, 0.59], calibration slope: 0.45). At a group level, Complement C8B, C4B, C5, and leucine-rich α-2 glycoprotein 1 (LRG1) were associated with transition to psychosis but did not surpass correction for multiple comparisons. This study did not confirm the findings from a previous proteomic prediction model of transition from CHR to psychosis. Certain complement proteins may be weakly associated with transition at a group level. Previous findings, derived from small samples, should be interpreted with caution.

Association between Plasma LRG1 and Lower Cognitive Function in Asians with Type 2 Diabetes Mellitus.

Leucine-rich α-2-glycoprotein 1 (LRG1) has been implicated in the pathogenesis of diabetic complications, but its association with cognitive function remains unclear. Our primary objective is to investigate the longitudinal association between LRG1 and cognitive function in patients with type 2 diabetes mellitus (T2DM). Secondarily, we determine the causal relationship using Mendelian Randomization (MR), and the role of arterial stiffness as a potential mediator. T2DM patients (n = 1039; age = 64.1 ± 6.4 years) were followed-up for 5.3 ± 1.2 years. Plasma LRG1 was measured at baseline using enzyme-linked immunosorbent assay. Baseline and follow-up cognitive function was assessed using Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). One-sample MR was performed with rs4806985 as plasma LRG1-associated single-nucleotide polymorphism (SNP). Mediation analysis was performed to examine if pulse wave velocity (PWV), an arterial stiffness index, mediated the association between plasma LRG1 and follow-up cognitive function. Elevated baseline natural log (Ln)-transformed LRG1 was inversely associated with baseline and follow-up RBANS total score with adjusted coefficients -1.38 (95%CI -2.55 to -0.21; p = 0.021) and -1.38 (95%CI -2.70 to -0.07; p = 0.039), respectively. Genetically-predicted higher levels of plasma LRG1 was associated with lower follow-up RBANS total score with coefficient -7.44 (95%CI -14.14 to -0.74; p = 0.030) per unit increase in LnLRG1. Higher PWV accounted for 27.7% of the association between LnLRG1 and follow-up RBANS total score. Baseline plasma LRG1 was associated with lower cognitive function at follow-up in patients with T2DM, mediated by PWV. MR analysis provided evidence of an association between genetically influenced plasma LRG1 and lower cognitive function at follow-up.

Keratinocyte-to-macrophage communication exacerbate psoriasiform dermatitis via LRG1-enriched extracellular vesicles.

Rationale: Macrophage-associated inflammation and keratinocytes excessive proliferation and inflammatory cytokines secretion induced by stimulation play an important role in the progression of psoriasiform dermatitis. However, how these two types of cells communicate remains obscure. Methods: We induced a mouse model with experimental psoriasiform dermatitis by Imiquimod (IMQ). To investigate whether damaged keratinocytes promote macrophage polarization and accelerate skin lesions by releasing extracellular vesicle (EV), purified EV were isolated from the primary epidermis of 5-day IMQ-induced psoriasiform dermatitis model mice, and then fluorescence-labeled the EV with PKH67. The EV was injected into the skin of mice treated with IMQ or vehicle 2 days in situ. In addition, we established a co-culture system of the human monocytic cell line (THP-1) and HaCaT, and THP-1/HaCaT conditioned media culture model in vitro respectively. Subsequently, we evaluated the effect of Leucine-rich α-2-glycoprotein 1 (LRG1)-enriched EV on macrophage activation. Results: We demonstrated macrophages can significantly promote keratinocyte inflammation and macrophage polarization may be mediated by intercellular communication with keratinocytes. Interestingly, IMQ-induced 5-day, keratinocyte-derived EV recruited macrophage and enhanced the progression of skin lesions. Similar to results in vivo, EV released from M5-treated HaCaT significantly promotes Interleukin 1β (IL-1β) and Tumor necrosis factor α (TNF-α) expression of THP-1 cells. Importantly, we found that LRG1-enriched EV regulates macrophages via TGF beta Receptor 1 (TGFβR1) dependent process. Conclusion: Our findings indicated a novel mechanism for promoting psoriasiform dermatitis, which could be a potential therapeutic target.

Leucine-Rich Alpha-2 Glycoprotein 1 Accumulates in Complicated Atherosclerosis and Promotes Calcification.

Atherosclerosis is the primary cause of cardiovascular disease. The development of plaque complications, such as calcification and neo-angiogenesis, strongly impacts plaque stability and is a good predictor of mortality in patients with atherosclerosis. Despite well-known risk factors of plaque complications, such as diabetes mellitus and chronic kidney disease, the mechanisms involved are not fully understood. We and others have identified that the concentration of circulating leucine-rich α-2 glycoprotein 1 (LRG1) was increased in diabetic and chronic kidney disease patients. Using apolipoprotein E knockout mice (ApoE-/-) (fed with Western diet) that developed advanced atherosclerosis and using human carotid endarterectomy, we showed that LRG1 accumulated into an atherosclerotic plaque, preferentially in calcified areas. We then investigated the possible origin of LRG1 and its functions on vascular cells and found that LRG1 expression was specifically enhanced in endothelial cells via inflammatory mediators and not in vascular smooth muscle cells (VSMC). Moreover, we identified that LRG1 was able to induce calcification and SMAD1/5-signaling pathways in VSMC. In conclusion, our results identified for the first time that LRG1 is a direct contributor to vascular calcification and suggest a role of this molecule in the development of plaque complications in patients with atherosclerosis.

Relationship between plasma leucine-rich α-2-glycoprotein 1 and urinary albumin excretion in patients with type 2 diabetes.

To explore the relationship between plasma leucine-rich α-2-glycoprotein 1 (LRG1) level and the degree of urinary albumin excretion in patients with type 2 diabetes. We evaluated 332 patients with type 2 diabetes in a cross-sectional study. The plasma LRG1 level differed significantly according to the quartiles of urinary albumin excretion (Q1 [<7.7 mg/g], 17.1 μg/mL; Q2 [7.7-15.0 mg/g], 17.5 μg/mL; Q3 [15.1-61.4 mg/g], 18.6 μg/mL; Q4 [≥61.5 mg/g], 22.3 μg/mL; p for trend = 0.003) under adjustment with other covariates. A positive correlation was found between plasma LRG1 level and urinary albumin excretion (ρ = 0.256, p <0.001). According to a multivariate model, the association between LRG1 and urinary albumin excretion remained significant, under adjustment for confounding factors (β = 0.285, p <0.001). Plasma LRG1 level was independently associated with urinary albumin excretion in patients with type 2 diabetes. This study suggests that LRG1 may be associated with increased excretion of urinary albumin in the early stages of diabetic nephropathy.

Biomarkers in the Pathogenesis, Diagnosis, and Treatment of Systemic Sclerosis.

Systemic sclerosis (SSc) is a complex autoimmune disease characterized by vascular damage, vasoinstability, and decreased perfusion with ischemia, inflammation, and exuberant fibrosis of the skin and internal organs. Biomarkers are analytic indicators of the biological and disease processes within an individual that can be accurately and reproducibly measured. The field of biomarkers in SSc is complex as recent studies have implicated at least 240 pathways and dysregulated proteins in SSc pathogenesis. Anti-nuclear antibodies (ANA) are classical biomarkers with well-described clinical classifications and are present in more than 90% of SSc patients and include anti-centromere, anti-Th/To, anti-RNA polymerase III, and anti-topoisomerase I antibodies. Transforming growth factor-β (TGF-β) is central to the fibrotic process of SSc and is intimately intertwined with other biomarkers. Tyrosine kinases, interferon-1 signaling, IL-6 signaling, endogenous thrombin, peroxisome proliferator-activated receptors (PPARs), lysophosphatidic acid receptors, and amino acid metabolites are new biomarkers with the potential for developing new therapeutic agents. Other biomarkers implicated in SSc-ILD include signal transducer and activator of transcription 4 (STAT4), CD226 (DNAX accessory molecule 1), interferon regulatory factor 5 (IRF5), interleukin-1 receptor-associated kinase-1 (IRAK1), connective tissue growth factor (CTGF), pyrin domain containing 1 (NLRP1), T-cell surface glycoprotein zeta chain (CD3ζ) or CD247, the NLR family, SP-D (surfactant protein), KL-6, leucine-rich α2-glycoprotein-1 (LRG1), CCL19, genetic factors including DRB1 alleles, the interleukins (IL-1, IL-4, IL-6, IL-8, IL-10 IL-13, IL-16, IL-17, IL-18, IL-22, IL-32, and IL-35), the chemokines CCL (2,3,5,13,20,21,23), CXC (8,9,10,11,16), CX3CL1 (fractalkine), and GDF15. Adiponectin (an indicator of PPAR activation) and maresin 1 are reduced in SSc patients. A new trend has been the use of biomarker panels with combined complex multifactor analysis, machine learning, and artificial intelligence to determine disease activity and response to therapy. The present review is an update of the various biomarker molecules, pathways, and receptors involved in the pathology of SSc.

Increased expression of leucine-rich α-2 glycoprotein 1 as a predictive biomarker of favorable progression-free survival in meningioma.

Most meningiomas, which are frequent central nervous system tumors, are classified as World Health Organization (WHO) grade 1 because of their slow-growing nature. However, the recurrence rate varies and is difficult to predict using conventional histopathological diagnoses. Leucine-rich α-2 glycoprotein 1 (LRG1) is involved in cell signal transduction, cell adhesion, and DNA repair and is a predictive biomarker in different malignant tumors; however, such a relationship has not been reported in meningiomas. We examined tissue microarrays of histological samples from 117 patients with grade 1 and 2 meningiomas and assessed their clinical and pathological features, including expression of LRG1 protein. LRG1-high meningiomas showed an increased number of vessels with CD3-positive cell infiltration (P = 0.0328) as well as higher CD105-positive vessels (P = 0.0084), as compared to LRG1-low cases. They also demonstrated better progression-free survival (hazard ratio [HR] 0.11, 95% confidence interval [CI] 0.016-0.841) compared to LRG1-low patients (P = 0.033). Moreover, multivariate analysis indicated that high LRG1 expression was an independent prognostic factor (HR, 0.13; 95% CI, 0.018-0.991; P = 0.049). LRG1 immunohistochemistry may be a convenient tool for estimating the prognosis of meningiomas in routine practice. Further studies are required to elucidate the key role of LRG1 in meningioma progression.

The Leucine-Rich α2-Glycoprotein-1 Levels in Patients with Multiple Myeloma

Introduction: Angiogenesis is considered important in the pathogenesis of multiple myeloma (MM), as well as in the targeted treatment of the disease. Leucine-rich α2-glycoprotein 1 (LRG1) is a protein that participates in angiogenesis and its effect on solid organ tumors has been investigated recently. This study aimed to investigate the relationship between MM and LRG1. Methods: The MM patients who admitted to Hatay Mustafa Kemal University Hematology Clinic between September 2021 and October 2022 were included in the study. The study consists of a total of 4 groups: newly diagnosed MM (NDMM), relapsed refractory MM (RRMM), MM in remission (Rem-MM), and control group. Demographic data were retrieved from hospital records. Blood samples of our study groups were centrifuged at 1,500 × g for 10 min and serum was collected. LRG1, IL-6, IL-8, TGF-β1, HIF-1α, FGF-2, and VEGF levels were analyzed in all groups by ELISA method, and statistical analysis was performed. Results: A total of 112 individuals, including NDMM (n: 27), RRMM (n: 18), Rem-MM (n: 42), and control group (n: 25), were enrolled in the study. Based on the analyses, the NDMM group exhibited significantly elevated levels of LRG1 (p < 0.001), TGF-1 (p < 0.001), and HIF-1α (p = 0.046, p < 0.001, and p = 0.003 compared to the RRMM, Rem-MM, and control groups, respectively) compared to the other groups. LRG1 levels were positively correlated with creatinine (r: 0.363, p = 0.001), calcium (r: 0.344, p = 0.001), total protein (r: 0.473, p < 0.001), erythrocyte sedimentation rate (r: 0.547, p < 0.001), lactate dehydrogenase (r: 0.321, p = 0.003), beta-2-microglobulin (r: 0.312, p = 0.017), IL-6 (r: 0.478, p < 0.001), IL-8 (r: 0.240, p = 0.03), TGF-β1 (r: 0.521, p < 0.001), and HIF-1α (r: 0.321, p = 0.003) levels and were negatively correlated with hemoglobin (r: −0.512, p < 0.001) and albumin (r: −0.549, p < 0.001) levels. Receiver operating characteristics (ROC) analysis revealed the association of LRG1 with the highest AUC value of 0.959 (95% CI: 0.904–1, p < 0.001) and the optimal cut-off value of 534.95 ng/mL (sensitivity: 93% and specificity: 99%) in the NDMM group compared to the control group. Conclusion: In this study, providing data for the first time on LRG1 levels in the setting of MM. LRG1 levels were found to be significantly higher in NDMM patients and in our study discriminate this patient population from RRMM, Rem-MM, and normal controls. Therefore, LRG1 seems to a potential biomarker that should be evaluated in future studies addressing the diagnosis, staging, follow-up, prognosis, and treatment target of MM.

Correlation of Leucine-Rich-α-2-Glycoprotein- 1 (LRG-1) Level in Urine with Cervical Cancer Stage, Histology Type and Histology Grading

Objective: To determine if the level of LRG-1 in urine correlates with cervical cancer stage, histology type and histology grading Method: This cross-sectional study using ELISA to test urinary LRG-1 of 59 cervical cancer patients. Data were analyzed using Kruskal-Wallis test. Results: From the total of 59 samples, LRG-1 in urine ranged from 0.48 ng/mL to 170.43 ng/mL, with median value 58.42 ng/mL. A median value of 21.42±52.29 ng/mL was found in the urine at early stage and 115.32±59.36 ng/mL at advanced stage. Most patients had cervical cancer at advanced stage (69.4%), squamous cell carcinoma (66.1%), and grade cannot be assessed (45.8%). Median LRG-1 levels were highest in squamous cell carcinoma (66.42±60.89 ng/mL) and poorly differentiated (127.74 ±54.13 ng/mL). LRG-1 levels were significantly correlated with cervical cancer stage (p-value=0.045) but not histological type (p-value=0.940) or histopathological grade (p-value=0.488). Conclusion: The more advanced the cervical cancer stage, the more elevated urinary LRG-1 levels. LRG-1 contributes to angiogenesis and antiapoptotic processes in cancer. Further studies are required to identify and evaluate LRG-1 in urine as an important biomarker for making clinical decisions and developing potential treatments.

Correlation of Leucine-Rich-α-2-Glycoprotein- 1 (LRG-1) Level in Urine with Cervical Cancer Stage, Histology Type and Histology Grading

Objective: To determine if the level of LRG-1 in urine correlates with cervical cancer stage, histology type and histology gradingMethod: This cross-sectional study using ELISA to test urinary LRG-1 of 59 cervical cancer patients. Data were analyzed using Kruskal-Wallis test.Results: From the total of 59 samples, LRG-1 in urine ranged from 0.48 ng/mL to 170.43 ng/mL, with median value 58.42 ng/mL. A median value of 21.42±52.29 ng/mL was found in the urine at early stage and 115.32±59.36 ng/mL at advanced stage. Most patients had cervical cancer at advanced stage (69.4%), squamous cell carcinoma (66.1%), and grade cannot be assessed (45.8%). Median LRG-1 levels were highest in squamous cell carcinoma (66.42±60.89 ng/mL) and poorly differentiated (127.74 ±54.13 ng/mL). LRG-1 levels were significantly correlated with cervical cancer stage (p-value=0.045) but not histological type (p-value=0.940) or histopathological grade (p-value=0.488).Conclusion: The more advanced the cervical cancer stage, the more elevated urinary LRG-1 levels. LRG-1 contributes to angiogenesis and antiapoptotic processes in cancer. Further studies are required to identify and evaluate LRG-1 in urine as an important biomarker for making clinical decisions and developing potential treatments.Hubungan Kadar Protein Leucine-Rich-α-2-Glycoprotein-1 (LRG-1) Urine dengan Stadium, Tipe Histologis, dan Derajat Diferensiasi Kanker ServiksAbstrakTujuan: Untuk mengetahui hubungan kadar LRG-1 dalam urine dengan stadium, tipe histologis, dan derajat diferensiasi kanker serviks.Metode: Studi ini menggunakan desain penelitian cross-sectional pada 59 perempuan yang telah didiagnosis kanker serviks, kemudian diperiksa kadar protein LRG-1 dalam urine dengan metode ELISA. Uji statistik menggunakan Kruskal Wallis. Hasil: Dari total 59 sampel didapatkan kadar LRG-1 dalam urine terendah 0,48 ng/mL dan tertinggi 170,43 ng/mL, nilai median 58,42 ng/mL. Nilai median pada stadium awal 21,42±52,29 ng/mL dan stadium lanjut 115,32±59,36 ng/mL. Lebih banyak penderita mengalami kanker serviks pada stadium lanjut (69,4%), tipe histopatologis Squamous Cell Carcinoma (66,1%), derajat diferensiasi tidak dapat ditentukan (45,8%). Median tertinggi kadar LRG-1 pada tipe Squamous Cell Carcinoma (66,42±60,89 ng/mL), dan derajat diferensiasi yang buruk (127,74±54,13 ng/mL). Terdapat hubungan yang signifikan antara kadar LRG-1 dan stadium kanker serviks (nilai p = 0,045), tetapi tidak dengan tipe histologis (nilai p=0,940) dan derajat diferensiasi (nilai p=0,488).Kesimpulan: Semakin tinggi stadium maka semakin tinggi kadar protein LRG-1 dalam urine. LRG-1 berperan dalam proses angiogenesis dan antiapoptosis pada kanker. Diperlukan penelitian lebih lanjut agar identifikasi dan evaluasi biomarker LRG-1 urine dapat menjadi penanda penting yang membantu dalam pengambilan keputusan klinis, serta pengembangan terapi.Kata Kunci: Derajat diferensiasi, Kanker serviks, LRG-1, Stadium, Tipe histologis

LRG1 Associates with Iron Deficiency Anemia Markers in Adolescents.

Leucine-rich α-2 glycoprotein1 (LRG1) has been shown to be associated with several health conditions; however, its association with iron deficiency anemia, especially in children, has not been previously explored. In this study, we investigated the association between LRG1 and several iron deficiency anemia markers, including hemoglobin (Hb), albumin, red cell distribution width (RDW), iron, ferritin, and Hb transferrin saturation. A total of 431 participants were included in this analysis aged between 11 and 14 years. Higher LRG1 levels were observed in children diagnosed with anemia [31.1 (24.6, 43.2) µg/mL] compared to non-anemic children [29.2 (22.7-35.95) µg/mL]. Statistically significant differences of LRG1 level across the three groups (tertiles) of Hb, iron, transferrin saturation, albumin, RDW, ferritin, and WBC were observed. Strong negative correlations were observed between LRG1 and Hb (Spearman's rho = -0.11, p = 0.021), albumin (Spearman's rho = -0.24, p < 0.001), iron (Spearman's rho = -0.25, p < 0.001), and Hb transferrin saturation (Spearman's rho = -0.24, p < 0.001), whereas circulating LRG1 levels were positively associated with RDW (Spearman's rho = 0.21, p < 0.001). In conclusion, our findings demonstrate for the first time the strong association between iron deficiency anemia markers and LRG1 in otherwise healthy school-aged children. However, further studies are needed to corroborate those results and to look for similar associations in other population subgroups.

Plasma leucine-rich α-2-glycoprotein 1 - a novel marker of diabetic kidney disease in children and adolescents with type 1 diabetes mellitus?

Glomerular endothelial dysfunction and neoangiogenesis play a significant role in the pathogenesis of diabetic kidney disease (DKD). Leucine-rich α-2 glycoprotein 1 (LRG1) is a recently discovered protein that participates in the molecular pathway of inflammation and angiogenesis. We aimed to investigate efficacy of LRG1 to predict estimated glomerular filtration rate (eGFR) decrease in children and adolescents with type 1 diabetes mellitus (T1DM). The study comprised 72 participants with diabetes duration for ≥ 2years. At study initiation, LRG1, urine albumin, eGFR (cystatin C-based, and Schwartz), HbA1c, and lipid values were evaluated and diabetes-related clinical features and anthropometric measurements were collected. These results were compared with final control values after ≥ 1year. Patients were divided into subgroups according to presence of albuminuria progression, eGFR decrease, and metabolic control parameters. There was positive correlation between LRG1 level and Schwartz and cystatin C-based eGFR decline (r = 0.360, p = 0.003; r = 0.447, p = 0.001, respectively), and negative correlation between final cystatin C-based eGFR and LRG1 (p = 0.01, r = -0.345). Patients with cystatin C-based eGFR decrease > 10% had significantly higher LRG1 levels (p = 0.03), however, LRG1 was not different between albuminuria progression subgroups. A 0.282μg/ml increase in LRG1 correlated with a 1% decrease in eGFR in simple linear regression analysis (β = 0.282, %CI 0.11-0.45, p = 0.001) and LRG1 was an independent predictor of GFR decline even in the presence of covariates. Our study supports the relationship between plasma LRG1 and eGFR decline and suggests LRG1 may be an early marker of DKD progression in children with T1DM. A higher resolution version of the Graphical abstract is available as Supplementary information.

SIRT2 regulates extracellular vesicle-mediated liver–bone communication

The interplay between liver and bone metabolism remains largely uncharacterized. Here, we uncover a mechanism of liver-bone crosstalk regulated by hepatocyte SIRT2. We demonstrate that hepatocyte SIRT2 expression is increased in aged mice and elderly humans. Liver-specific SIRT2 deficiency inhibits osteoclastogenesis and alleviates bone loss in mouse models of osteoporosis. We identify leucine-rich α-2-glycoprotein 1 (LRG1) as a functional cargo in hepatocyte-derived small extracellular vesicles (sEVs). In SIRT2-deficient hepatocytes, LRG1 levels in sEVs are upregulated, leading to increased transfer of LRG1 to bone-marrow-derived monocytes (BMDMs), and in turn, to inhibition of osteoclast differentiation via reduced nuclear translocation of NF-κB p65. Treatment with sEVs carrying high levels of LRG1 inhibits osteoclast differentiation in human BMDMs and in mice with osteoporosis, resulting in attenuated bone loss in mice. Furthermore, the plasma level of sEVs carrying LRG1 is positively correlated with bone mineral density in humans. Thus, drugs targeting hepatocyte-osteoclast communication may constitute a promising therapeutic strategy for primary osteoporosis.

Diagnostic Utility of Serum Leucine-Rich α-2-Glycoprotein 1 for Acute Appendicitis in Children.

The aim of this study is to assess the diagnostic utility of serum leucine-rich α-2-glycoprotein 1 (LRG1) in pediatric patients with acute abdominal pain, admitted to the emergency surgical unit, in order to make a prompt and accurate diagnosis of acute appendicitis. Pediatric patients older than 5 years of age who presented to the emergency department from 15 October 2021 to 30 June 2022 with acute abdominal pain and suspected acute appendicitis were prospectively recruited in the study. Demographic and clinical data, as well as operative and postoperative data, were recorded. A total of 92 patients were equally distributed into two groups: children with acute appendicitis who underwent laparoscopic appendectomy and non-appendicitis patients, presenting with non-specific abdominal pain. LRG1 levels were determined using a commercially available LRG1 enzyme-linked immunosorbent assay (ELISA) kit. Serum LRG1 levels, as well as other inflammatory markers (white blood cell count (WBC), C-reactive protein (CRP) and absolute neutrophil count) were compared between groups. The median level of LRG1 in serum was significantly higher in the group of children with pathohistologically confirmed acute appendicitis than in the control group, at 350.3 µg/mL (interquartile range (IQR) 165.2-560.3) and 25.7 µg/mL (IQR 14.7-36.8) (p < 0.001), respectively. Receiver operating characteristic area under the curve for LRG1 from serum was 1.0 (95% CI 0.96-1.00; p < 0.001) and the value of >69.1 µg/mL was found to perfectly separate acute appendicitis cases from controls. Additionally, as expected, each of the examined laboratory inflammatory markers provided a significantly higher values in the acute appendicitis group compared to the control group: WBC 14.6 × 109/L (IQR 12.7, 18.7) vs. 7.0 × 109/L (IQR 5.4, 9.0) (p < 0.001), CRP 16.3 mg/dL (IQR 6.9, 50.4) vs. 2.2 mg/dL (IQR 2, 2) (p < 0.001) and absolute neutrophil count 84.6% (IQR 79.5, 89.0) vs. 59.5% (IQR 51.5, 68.6) (p < 0.001). LRG1 in the serum was found to be a promising novel biomarker, with excellent differentiation of acute appendicitis from non-appendicitis cases in children presenting with non-specific abdominal pain.