Gal-1-mediated cytochrome p450 activation promotes fibroblast into myofibroblast differentiation in pulmonary fibrosis

Pulmonary fibrosis (PF) results from excessive extracellular matrix (ECM) deposition and tissue remodeling after activation of fibroblasts into myofibroblasts. Abnormally deposited fibrotic ECM, in turn, promotes fibroblast activation and accelerates loss of lung structure and function. However, the molecular mediators and exact mechanisms by which fibrotic ECM promotes fibroblast activation are unclear. In a bleomycin-induced PF mouse model, we found Galectin-1 (Gal-1) expression was significantly increased in lung tissue, and overexpression of Gal-1 plasmid-transfected fibroblasts were activated into myofibroblasts. Using the decellularization technique to prepare decellularized fibrotic ECM and constructing a 3D in vitro co-culture system with fibroblasts, we found that decellularized fibrotic ECM induced a high expression of Gal-1 and promoted the activation of fibroblasts into myofibroblasts. Therefore, Gal-1 has been identified as a pivotal mediator in PF. Further, we found that decellularized fibrotic ECM delivered mechanical signals to cells through the Gal-1-mediated FAK-Src-P130Cas mechanical signalling pathway, while the CYP450 enzymes (mainly involved in CYP1A1, CYP24A1, CYP3A4, and CYP2D6 isoforms) acted as a chemical signalling pathway to receive mechanical signals transmitted from upstream Gal-1, thereby promoting fibroblast activation. The Gal-1 inhibitor OTX008 or the CYP1A1 inhibitor 7-Hydroxyflavone prevented PF in mice and inhibited the role of fibrotic ECM in promoting fibroblast activation into myofibroblasts, preventing PF. These results reveal novel molecular mechanisms of lung fibrosis formation and identify Gal-1 and its downstream CYP1A1 as potential therapeutic targets for PF disease treatmnts.

Diosgenin upregulates axonal guidance partner molecules, Galectin-1 and Secernin-1

Galectin-1, a β-galactosides-binding protein, is widely expressed in various tissues and exhibits diverse biological activities. We previously obtained following findings; 1) Diosgenin, a steroid sapogenin, promoted axonal regeneration in the brain and recovered memory deficits in a model of Alzheimer's disease (AD), 5XFAD mouse; 2) Neuron-specific overexpression of Galectin-1 protein in the hippocampus recovered memory impairment and promoted axonal regeneration in the brain in 5XFAD mice; 3) Secernin-1, a counterpart and axonal guidance molecule for Galectin-1-expressing axons, was secreted from the prefrontal cortical neurons to promote axonal guidance from the hippocampus to the prefrontal cortex. However, it has never been elucidated that diosgenin signaling increase Galectin-1 and Secernin-1 or not. Here, we found that diosgenin treatment upregulated the protein level of Galectin-1 in the hippocampus both in primary cultured neurons and in 5XFAD mouse brains. In addition, diosgenin-induced upregulation of Galectin-1 was diminished by treatment of a neutralizing antibody of 1,25D3-membrane-associated rapid response steroid-binding receptor (1,25D3-MARRS), a direct binding receptor for diosgenin. Importantly, knockdown of Galectin-1 in hippocampal neurons inhibited axonal growth activity of diosgenin. Furthermore, the expression level of Secernin-1 was also increased in prefrontal cortical neurons by administration of diosgenin to 5XFAD mice. These findings suggest that diosgenin is a suitable compound to facilitate Galectin-1-Secernin-1-mediated axonal growth in AD brains.

Ganoderic acid T, a Ganoderma triterpenoid, modulates the tumor microenvironment and enhances the chemotherapy and immunotherapy efficacy through downregulating galectin-1 levels

Ganoderic acid T (GAT), a triterpenoid molecule of Ganoderma lucidum, exhibits anti-cancer activity; however, the underlying mechanisms remain unclear. Therefore, in this study, we aimed to investigate the anti-cancer molecular mechanisms of GAT and explore its therapeutic applications for cancer treatment. GAT exhibited potent anti-cancer activity in an ES-2 orthotopic ovarian cancer model in a humanized mouse model, leading to significant alterations in the tumor microenvironment (TME). Specifically, GAT reduced the proportion of α-SMA+ cells and enhanced the infiltration of tumor-infiltrating lymphocytes (TILs) in tumor tissues. After conducting proteomic analysis, it was revealed that GAT downregulates galectin-1 (Gal-1), a key molecule in the TME. This downregulation has been confirmed in multiple cancer cell lines and xenograft tumors. Molecular docking suggested a theoretical direct interaction between GAT and Gal-1. Further research revealed that GAT induces ubiquitination of Gal-1. Moreover, GAT significantly augmented the anti-cancer effects of paclitaxel, thereby increasing intratumoral drug concentrations and reducing tumor size. Combined with immunotherapy, GAT enhanced the tumor-suppressive effects of the anti-programmed death-ligand 1 antibody and increased the proportion of CD8+ cells in the EMT6 syngeneic mammary cancer model. In conclusion, GAT inhibited tumor growth, downregulated Gal-1, modulated the TME, and promoted chemotherapy and immunotherapy efficacy. Our findings highlight the potential of GAT as an effective therapeutic agent for cancer.

High galectin expression in Helicobacter pylori-infected gastric mucosa in childhood

BACKGROUND

Mild Th1 and Th17 immune responses in childhood against Helicobacter pylori are presumed to be responsible for H. pylori colonization and mucosal atrophy reduction. However, the mechanism remains unclear. In this study, we aimed to investigate the childhood-specific immune responses observed after H. pylori infection by analyzing galectin expression in the gastric mucosa. We focused on galectin-1 (Gal-1) and galectin-9 (Gal-9), which function to suppress Th1 and Th17 immune responses.

METHODS

We analyzed changes in the expression of Gal-1 and Gal-9 in the gastric mucosa of pediatric patients with H. pylori infection. Ten pediatric patients with and ten patients without H. pylori infection who underwent biopsy to assess the cause of chronic abdominal symptoms using esophagogastroduodenoscopy were evaluated. Gal-1 and Gal-9 expression in the biopsy tissues of the gastric antrum and corpus was analyzed by immunohistochemical staining.

RESULTS

Gal-1 expression was significantly increased in the stromal cells of the corpus owing to H. pylori infection. No alterations in Gal-1 expression due to H. pylori infection were observed in the antral tissue. Helicobacter pylori infection considerably increased Gal-9 expression in all tissues. According to previous reports, the increased expression of Gal-9 associated with H. pylori infection is not observed in adults. Therefore, the increased expression of Gal-9 associated with H. pylori infection is specific to pediatric patients.

CONCLUSION

The increased expression of Gal-1 and Gal-9 may suppress Th1 and Th17 immune responses against H. pylori infection during childhood, promote H. pylori colonization, and reduce inflammation in the gastric mucosa of pediatric patients.

"Inhibitory immune checkpoints predict 7-day, in-hospital and 1-year mortality of internal medicine patients admitted with bacterial sepsis"

BACKGROUND

Sepsis is a life-threatening syndrome with complex pathophysiology and great clinical heterogeneity which complicates the delivery of personalized therapies. Our goals were to demonstrate that some biomarkers identified as regulatory immune checkpoints in preclinical studies could 1)improve sepsis prognostication based on clinical variables and 2)guide the stratification of septic patients in subgroups with shared characteristics of immune response or survival outcomes.

METHODS

We assayed the soluble counterparts of 12 biomarkers of immune response in 113 internal medicine patients with bacterial sepsis.

RESULTS

IL-1 receptor-associated kinase M (IRAK-M) exhibited the highest hazard ratios (HRs) for increased 7-day (1.94 [1.17-3.20]) and 30-day mortality (1.61 [1.14-2.28]). HRs of IRAK-M and Galectin-1 for predicting 1-year mortality were 1.52 (1.20-1.92) and 1.64 (1.13-2.36), respectively. A prognostic model including IRAK-M, Galectin-1, and clinical variables (Charlson Comorbidty Index, multiple source of sepsis, and SOFA score) had high discrimination for death at 7 days and 30 days (area under the curve 0.90 [0.82-0.99]) and 0.86 [0.79-0.94], respectively). Patients with elevated serum levels of IRAK-M and Galectin-1 had clinical traits of immune suppression and low survival rates. None of the 12 biomarkers were independent predictors of 2-year mortality.

CONCLUSIONS

Two inhibitory immune checkpoint biomarkers (IRAK-M and Galectin-1) helped identify 3 distinct sepsis phenotypes with distinct prognoses. These biomarkers shed light on the interplay between immune dysfunction and prognosis in patients with bacterial sepsis and may prove to be useful prognostic markers, therapeutic targets, and biochemical markers for targeted enrollment in targeted therapeutic trials.

Galectin-1 Promotes Gastric Carcinoma Progression and Cisplatin Resistance Through the NRP-1/c-JUN/Wee1 Pathway

PURPOSE

Gastric cancer (GC) is among the deadliest malignancies and the third leading cause of cancer-related deaths worldwide. Galectin-1 (Gal-1) is a primary protein secreted by cancer-associated fibroblasts (CAFs); however, its role and mechanisms of action of Gal-1 in GC remain unclear. In this study, we stimulated GC cells with exogenous human recombinant galectin-1 protein (rhGal-1) to investigate its effects on the proliferation, migration, and resistance to cisplatin.

MATERIALS AND METHODS

We used simulated rhGal-1 protein as a paracrine factor produced by CAFs to induce GC cells and investigated its promotional effects and mechanisms in GC progression and cisplatin resistance. Immunohistochemical (IHC) assay confirmed that Gal-1 expression was associated with clinicopathological parameters and correlated with the expression of neuropilin-1 (NRP-1), c-JUN, and Wee1.

RESULTS

Our study reveals Gal-1 expression was significantly associated with poor outcomes. Gal-1 boosts the proliferation and metastasis of GC cells by activating the NRP-1/C-JUN/Wee1 pathway. Gal-1 notably increases GC cell resistance to cisplatin The NRP-1 inhibitor, EG00229, effectively counteracts these effects.

CONCLUSIONS

These findings revealed a potential mechanism by which Gal-1 promotes GC growth and contributes to chemoresistance, offering new therapeutic targets for the treatment of GC.

Baseline levels of circulating galectin-1 associated with radiographic hand but not radiographic knee osteoarthritis at a two-year follow-up

Objective

We tested the potential of circulating galectin-1, interleukin (IL)-1 beta, IL-6, and tumour necrosis factor alpha (TNF alpha) levels at baseline in individuals with knee pain as biomarkers for development of radiographic knee and/or hand osteoarthritis (OA).

Design

This study comprised 212 individuals with knee pain from the Halland osteoarthritis cohort (HALLOA). Clinical characteristics and serum/plasma levels of galectin-1, IL-1 beta, IL-6, and TNF alpha were measured at baseline, and knee and hand radiographs were obtained at a two-year follow-up. The predictive value of circulating inflammatory markers and clinical variables at baseline was assessed using multinominal logistic regression for those who developed radiographic OA in knees only (n ​= ​25), in hands only (n ​= ​40), and in both knees and hands (n ​= ​43); the group who did not develop OA (n ​= ​104) was used as reference. Correlations were assessed using Spearman's correlation coefficients.

Results

As expected, age was identified as a risk factor for having radiographic knee and/or hand OA at the two-year follow-up. Baseline circulating galectin-1 levels did not associate with developing radiographic knee OA but associated with developing radiographic hand OA (odds ratio (OR) for a 20% increased risk: 1.14, 95% confidence interval (CI) 1.01-1.29) and both radiographic knee and hand OA (OR for a 20% increased risk: 1.18, 95% CI 1.05-1.30). However, baseline IL-1 beta, IL-6, and TNF alpha did not associate with developing radiographic knee and/or hand OA.

Conclusion

Non-age adjusted circulating galectin-1 is superior to IL-6, IL-1 beta, and TNF alpha in predicting radiographic hand but not knee OA.

Regulation of Nrf2/Keap1 signaling pathway in cancer drug resistance by galectin-1: cellular and molecular implications

Oxidative stress is characterized by the deregulation of the redox state in the cells, which plays a role in the initiation of various types of cancers. The activity of galectin-1 (Gal-1) depends on the cell redox state and the redox state of the microenvironment. Gal-1 expression has been related to many different tumor types, as it plays important roles in several processes involved in cancer progression, such as apoptosis, cell migration, adhesion, and immune response. The erythroid-2-related factor 2 (Nrf2)/Kelch-like ECH-associated protein 1 (Keap1) signaling pathway is a crucial mechanism involved in both cell survival and cell defense against oxidative stress. In this review, we delve into the cellular and molecular roles played by Gal-1 in the context of oxidative stress onset in cancer cells, particularly focusing on its involvement in activating the Nrf2/Keap1 signaling pathway. The emerging evidence concerning the anti-apoptotic effect of Gal-1, together with its ability to sustain the activation of the Nrf2 pathway in counteracting oxidative stress, supports the role of Gal-1 in the promotion of tumor cells proliferation, immuno-suppression, and anti-tumor drug resistance, thus highlighting that the inhibition of Gal-1 emerges as a potential strategy for the restraint and regression of tumor progression. Overall, a deeper understanding of the multi-functionality and disease-specific expression profiling of Gal-1 will be crucial for the design and development of novel Gal-1 inhibitors as anticancer agents. Excitingly, although it is still understudied, the ever-growing knowledge of the sophisticated interplay between Gal-1 and Nrf2/Keap1 will enable researchers to gain valuable insights into the underlying causes of carcinogenesis and metastasis.

Galectin inhibitors and nanoparticles as a novel therapeutic strategy for glioblastoma multiforme

Over the past two decades, the gold standard of glioblastoma multiforme (GBM) treatment is unchanged and adjunctive therapy has offered little to prolong both quality and quantity of life. To improve pharmacotherapy for GBM, galectins are being studied provided their positive correlation with the malignancy and disease severity. Despite the use of galectin inhibitors and literature displaying the ability of the lectin proteins to decrease tumor burden and decrease mortality within various malignancies, galectin inhibitors have not been studied for GBM therapy. Interestingly, anti-galectin siRNA delivered in nanoparticle capsules, assisting in blood brain barrier penetrance, is well studied for GBM, and has demonstrated a remarkable ability to attenuate both galectin and tumor count. Provided that the two therapies have an analogous anti-galectin effect, it is hypothesized that galectin inhibitors encapsuled within nanoparticles will likely have a similar anti-galectin effect in GBM cells and further correlate to a repressed tumor burden.

A prototype galectin-1 (also known as galecin-2) from large yellow croaker (Larimichthys crocea): Molecular and function study

Galectin-1 (also known as galecin-2), one member of galectins family, has multiple functions as a pattern recognition receptor (PRR) in innate immune defense system. In the present study, LcGal-1, a prototype galectin, was identified and function investigated in large yellow croaker (Larimichthys crocea). LcGal-1 consists of one carbohydrate recognition domain (CRD), which contains two carbohydrate binding motifs HFNPR and WG-E-R. LcGal-1 had a ubiquitous tissues profile with the highest and lowest expression in spleen and muscle, respectively. Moreover, it was in cytoplasm and nucleus of head-kidney cells in large yellow croaker. RT-qRCR showed that P. plecoglossicida induced LcGal-1 up-regulated expression in liver and gills, and the results were validated by immunohistochemistry analysis. Additionally, the recombinant LcGal-1 (rLcGal-1) showed agglutinate activity on erythrocytes, and the histidine (His) in the HFNPR motif was a key locus to the activity. The agglutination effect of rLcGal-1 on erythrocytes could be inhibited by LPS, α-lactase and d-galactose. The rLcGal-1 was able to bind and agglutinate Gram+ and Gram-bacteria, and damage bacterial membrane as confirmed by PI staining and SEM observation. Transcriptome analysis showed that the overexpressed LcGal-1 in HEK 293T cells could induce 176 DGEs, including 172 boosting genes and 4 falling genes. Collectively, LcGal-1 was a key immune gene involved in the recognition, conjunction, and elimination of pathogens in L. crocea, as well as multiple physiological and pathological regulatory processes.

Serum Galectin-1, Galectin-9, and YKL-40 levels in bipolar disorder and their relationship with cognitive functions

PURPOSE

The number of studies conducted on the role of neuroinflammation in the etiopathogenesis of bipolar disorder has been increasing in recent years. The role of Galectin-1, Galectin-9, and YKL-40, which are considered to play roles in neuroinflammation and the etiopathogenesis of bipolar disorder, and the relationship of these parameters with cognitive functions were investigated in the present study.

METHOD

Serum Galectin-1, Galectin-9, and YKL-40 levels were measured with the ELISA Method in 64 bipolar euthymic patients and 64 healthy controls. The Stroop and trail-making tests were administered to assess cognitive functions in all participants.

RESULTS

Serum Galectin-1, Galectin-9, and YKL-40 levels were statistically and significantly lower in the patient group when compared to the healthy control group. The scores of the Stroop test and trail-making tests were statistically higher in the patient group than in the healthy control group. There was a weak and positive correlation between serum Galectin-1, Galectin-9, and YKL-40 levels and cognitive performance in all participants.

DISCUSSION AND CONCLUSION

Statistically significant low levels of serum Galectin-1, Galectin-9, and YKL-40 detected in the patient group suggest that these parameters have important roles in neuroinflammation. The statistically higher Stroop and trail-making test scores of the patient group compared to the control group indicates that the cognitive performance of the patient group was weaker. Also, the positive correlation between Galectin-1, Galectin-9, and YKL-40 levels and cognitive performance suggests that these molecules may have a neuroprotective role. We think that the present study will contribute to this field where there is very limited data in the literature.

Myeloid leukemia-derived galectin-1 downregulates CAR expression to hinder cytotoxicity of CAR T cells

BACKGROUND

Chimeric antigen receptor (CAR) T cells have shown significant activity in B-lineage malignancies. However, their efficacy in myeloid leukemia has not been successful due to unclear molecular mechanisms.

METHODS

We conducted in vitro and in vivo experiments to investigate whether myeloid leukemia cells directly induce CAR down-regulation. Furthermore, we designed a CD33 CARKR in which all lysines in the cytoplasmic domain of CAR were mutated to arginine and verified through in vitro experiments that it could reduce the down-regulation of surface CARs and enhance the killing ability. Transcriptome sequencing was performed on various AML and ALL cell lines and primary samples, and the galectin-1-specific inhibitory peptide (anginex) successfully rescued the killing defect and T-cell activation in in vitro assays.

RESULTS

CAR down-regulation induced by myeloid leukemia cells under conditions of low effector-to-tumor ratio, which in turn impairs the cytotoxicity of CAR T cells. In contrast, lysosomal degradation or actin polymerization inhibitors can effectively alleviate CAR down-regulation and restore CAR T cell-mediated anti-tumor functions. In addition, this study identified galectin-1 as a critical factor used by myeloid leukemia cells to induce CAR down-regulation, resulting in impaired T-cell activation.

CONCLUSION

The discovery of the role of galectin-1 in cell surface CAR down-regulation provides important insights for developing strategies to restore anti-tumor functions.

Molecular characterization and functional analysis of galectin-1 from silver pomfret (Pampus argenteus)

Galectins, as members of lectin families, exhibit a high affinity for β-galactosides and play diverse roles in biological processes. They function as pattern recognition receptors (PRRs) with important roles in immune defense. In this study, galectin-1, designated as SpGal-1, was identified and characterized from silver pomfret (Pampus argenteus). The SpGal-1 comprises an open reading frame (ORF) spanning 396 base pairs (bp) and encodes a deduced amino acid (aa) sequence containing a single carbohydrate recognition domain (CRD). Sublocalization analysis revealed that SpGal-1 was mainly expressed in the cytoplasm. The mRNA transcripts of SpGal-1 were ubiquitously detected in various tissues, with a higher expression level in the intestine. In addition, when exposed to Photobacterium damselae subsp. damselae (PDD) infection, both the liver and head kidney exhibited significantly increased SpGal-1 mRNA expression. The recombinant protein of SpGal-1 (named as rSpGal-1) demonstrated hemagglutination against red blood cells (RBCs) from Larimichthys crocea and P. argenteus in a Ca2+ or β-Mercaptoethanol (β-ME)-independent manner. Notably, rSpGal-1 could bind with various pathogen-associated molecular patterns (PAMPs) including D-galactose, D-mannose, lipopolysaccharide (LPS), and peptidoglycan (PGN), with highest affinity to PGN. Moreover, rSpGal-1 effectively interacted with an array of bacterial types encompassing Gram-positive bacteria (Staphylococcus aureus and Nocardia seriolae) and Gram-negative bacteria (PDD and Escherichia coli, among others), with the most robust binding affinity towards PDD. Collectively, these findings highlight that SpGal-1 is a crucial PRR with involvement in the host immune defense of silver pomfret.

Oxidized galectin-1 in SLE fails to bind the inhibitory receptor VSTM1 and increases reactive oxygen species levels in neutrophils

Inhibitory immune receptors set thresholds for immune cell activation, and their deficiency predisposes a person to autoimmune responses. However, the agonists of inhibitory immune receptors remain largely unknown, representing untapped sources of treatments for autoimmune diseases. Here, we show that V-set and transmembrane domain-containing 1 (VSTM1) is an inhibitory receptor and that its binding by the competent ligand soluble galectin-1 (Gal1) is essential for maintaining neutrophil viability mediated by downregulated reactive oxygen species production. However, in patients with systemic lupus erythematosus (SLE), circulating Gal1 is oxidized and cannot be recognized by VSTM1, leading to increased intracellular reactive oxygen species levels and reduced neutrophil viability. Dysregulated neutrophil function or death contributes significantly to the pathogenesis of SLE by providing danger molecules and autoantigens that drive the production of inflammatory cytokines and the activation of autoreactive lymphocytes. Interestingly, serum levels of glutathione, an antioxidant able to convert oxidized Gal1 to its reduced form, were negatively correlated with SLE disease activity. Taken together, our findings reveal failed inhibitory Gal1/VSTM1 pathway activation in patients with SLE and provide important insights for the development of effective targeted therapies.

Galectin-1 as a marker for microglia activation in the aging brain

Microglia cells, the immune cells residing in the brain, express immune regulatory molecules that have a central role in the manifestation of age-related brain characteristics. Our hypothesis suggests that galectin-1, an anti-inflammatory member of the beta-galactoside-binding lectin family, regulates microglia and neuroinflammation in the aging brain. Through our in-silico analysis, we discovered a subcluster of microglia in the aged mouse brain that exhibited increased expression of galectin-1 mRNA. In our Western blotting experiments, we observed a decrease in galectin-1 protein content in our rat primary cortical cultures over time. Additionally, we found that the presence of lipopolysaccharide, an immune activator, significantly increased the expression of galectin-1 protein in microglial cells. Utilizing flow cytometry, we determined that a portion of the galectin-1 protein was localized on the surface of the microglial cells. As cultivation time increased, we observed a decrease in the expression of activation-coupled molecules in microglial cells, indicating cellular exhaustion. In our mixed rat primary cortical cell cultures, we noted a transition of amoeboid microglial cells labeled with OX42(CD11b/c) to a ramified, branched phenotype during extended cultivation, accompanied by a complete disappearance of galectin-1 expression. By analyzing the transcriptome of a distinct microglial subpopulation in an animal model of aging, we established a correlation between chronological aging and galectin-1 expression. Furthermore, our in vitro study demonstrated that galectin-1 expression is associated with the functional activation state of microglial cells exhibiting specific amoeboid morphological characteristics. Based on our findings, we identify galectin-1 as a marker for microglia activation in the context of aging.

Selective modifications of lactose and N-acetyllactosamine with sulfate and aromatic bulky groups unveil unique structural insights in galectin-1-ligand recognition

Galectins, a family of endogenous glycan-binding proteins, play crucial roles in a broad range of physiological and pathological processes. Galectin-1 (Gal-1), a proto-type member of this family, is overexpressed in several cancers and plays critical roles in tumor-immune escape, angiogenesis and metastasis. Thus, generation of high-affinity Gal-1 inhibitors emerges as an attractive therapeutic approach for a wide range of neoplastic conditions. Small-molecule carbohydrate inhibitors based on lactose (Lac) and N-acetyllactosamine (LacNAc) structures have been tested showing different results. In this study, we evaluated Lac- and LacNAc-based compounds with specific chemical modifications at key positions as Gal-1 ligands by competitive solid-phase assays (SPA) and isothermal titration calorimetry (ITC). Both assays showed excellent correlation, highlighting that lactosides bearing bulky aromatic groups at the anomeric carbon and sulfate groups at the O3' position exhibited the highest binding affinities. To dissect the atomistic determinants for preferential affinity of the different tested Gal-1 ligands, molecular docking simulations were conducted and PRODIGY-LIG structure-based method was employed to predict binding affinity in protein-ligand complexes. Notably, calculated binding free energies derived from the molecular docking were in accordance with experimental values determined by SPA and ITC, showing excellent correlation between theoretical and experimental approaches. Moreover, this analysis showed that 3'-O-sulfate groups interact with residues of the Gal-1 subsite B, mainly with Asn33, while the ester groups of the aromatic anomeric group interact with Gly69 and Thr70 at Gal-1 subsite E, extending deeper into the pocket, which could account for the enhanced binding affinity. This study contributes to the rational design of highly optimized Gal-1 inhibitors to be further studied in cancer models and other pathologic conditions.

Galectin-1 in Pancreatic Ductal Adenocarcinoma: Bridging Tumor Biology, Immune Evasion, and Therapeutic Opportunities

Pancreatic Ductal Adenocarcinoma (PDAC) remains one of the most challenging malignancies to treat, with a complex interplay of molecular pathways contributing to its aggressive nature. Galectin-1 (Gal-1), a member of the galectin family, has emerged as a pivotal player in the PDAC microenvironment, influencing various aspects from tumor growth and angiogenesis to immune modulation. This review provides a comprehensive overview of the multifaceted role of Galectin-1 in PDAC. We delve into its contributions to tumor stroma remodeling, angiogenesis, metabolic reprogramming, and potential implications for therapeutic interventions. The challenges associated with targeting Gal-1 are discussed, given its pleiotropic functions and complexities in different cellular conditions. Additionally, the promising prospects of Gal-1 inhibition, including the utilization of nanotechnology and theranostics, are highlighted. By integrating recent findings and shedding light on the intricacies of Gal-1's involvement in PDAC, this review aims to provide insights that could guide future research and therapeutic strategies.

Generation and characterization of a monoclonal antibody that binds to Galectin-1

Galectin-1 is a β-galactoside-binding lectin that has been implicated as a suppressive molecule in cancer and autoimmune diseases. Gal-1 has known immunomodulatory activity and was found to be expressed on regulatory T cells, leading to the potential for targeted immunotherapies. Anti-Gal-1 monoclonal antibodies were generated in this study using classical hybridoma techniques. MAb 6F3 was found to bind to Gal-1 by Western blot and ELISA. Flow cytometry was used to determine cell surface and intracellular binding of mAb 6F3 to Gal-1 in PBMC-derived Tregs and tumor cells, including Treg-like cell lines. These results suggest mAb 6F3 may be used to further study Gal-1 protein expression and function.

Expression and Significance of Galectin-1 and Galectin-3 in the Serum and Placental Tissues of Patients with Intrahepatic Cholestasis of Pregnancy

Background

Intrahepatic cholestasis of pregnancy (ICP) is a pregnancy-specific liver disease, usually occurring in the third trimester of pregnancy. Its typical clinical manifestations are itching and elevated serum total bile acid levels, which are more harmful to the fetus, and can lead to a variety of adverse pregnancy outcomes. This paper discusses the expressions of galectin -1 and 3 in the serum and placenta of ICP patients and their relationship with the effect of the incidence of ICP.

Methods

Galectin-1 and 3 in serum and placenta were detected in 22 pregnant women with ICP and 20 healthy pregnant women admitted to the obstetrics Department of Northern Jiangsu People's Hospital from May 2021 to February 2022.

Results

Serum levels of galectin-1 and galectin-3 in ICP pregnant women were significantly higher than those in controls, with significant differences (P<0.05). Placental galectin-1 and 3 were higher in normal pregnant women, and there were statistical differences between groups (P<0.05).

Conclusion

In ICP, the maternal serum and placental galectin-1 and 3 levels were significantly increased, both of which may play an important role in the development of ICP, which may be the initiation factor of ICP pathophysiology, a marker of ICP prediction, and a target of ICP prevention strategies.

Galectin-1-mediated MET/AXL signaling enhances sorafenib resistance in hepatocellular carcinoma by escaping ferroptosis

Sorafenib, a small-molecule inhibitor targeting several tyrosine kinase pathways, is the standard treatment for advanced hepatocellular carcinoma (HCC). However, not all patients with HCC respond well to sorafenib, and 30% of patients develop resistance to sorafenib after short-term treatment. Galectin-1 modulates cell-cell and cell-matrix interactions and plays a crucial role in HCC progression. However, whether Galectin-1 regulates receptor tyrosine kinases by sensitizing HCC to sorafenib remains unclear. Herein, we established a sorafenib-resistant HCC cell line (Huh-7/SR) and determined that Galectin-1 expression was significantly higher in Huh-7/SR cells than in parent cells. Galectin-1 knockdown reduced sorafenib resistance in Huh-7/SR cells, whereas Galectin-1 overexpression in Huh-7 cells increased sorafenib resistance. Galectin-1 regulated ferroptosis by inhibiting excessive lipid peroxidation, protecting sorafenib-resistant HCC cells from sorafenib-mediated ferroptosis. Galectin-1 expression was positively correlated with poor prognostic outcomes for HCC patients. Galectin-1 overexpression promoted the phosphorylation of AXL receptor tyrosine kinase (AXL) and MET proto-oncogene, receptor tyrosine kinase (MET) signaling, which increased sorafenib resistance. MET and AXL were highly expressed in patients with HCC, and AXL expression was positively correlated with Galectin-1 expression. These findings indicate that Galectin-1 regulates sorafenib resistance in HCC cells through AXL and MET signaling. Consequently, Galectin-1 is a promising therapeutic target for reducing sorafenib resistance and sorafenib-mediated ferroptosis in patients with HCC.

Elevated Serum Galectin-1 and Galectin-3 Levels in Children With Specific Learning Disorder: A Case Control Study

OBJECTIVE

Specific learning disorder (SLD) is a neurodevelopmental disorder in which underlying pathogenesis and etiological factors are not fully understood. Neuroinflammatory response (measured with serum levels of galectin-1 and galectin-3), which is associated with learning and memory, may play an important role in the etiopathogenesis of SLD. Aim of the present study is to examine whether serum galectin-1 and galectin-3 levels are related to SLD.

METHODS

The current study consisted of 42 treatment-naive children with SLD and 42 control subjects. All of the subjects were assessed using semi-structured psychiatric examination to diagnose SLD and exclude attention-deficit hyperactivity disorder. Serum galectin-1 and galectin-3 levels were measured via venous blood samples.

RESULTS

The SLD and control group did not differ significantly in terms of age, sex, and body mass index (BMI). The SLD group had significantly higher serum levels of galectin-1 (8.78±2.97 vs. 7.40±2.03, p=0.019) and galectin-3 (1.86±0.93 vs. 1.32±0.69, p=0.003) than the control group when controlled for age, sex, and BMI.

CONCLUSION

Higher serum levels of galectin-1 and galectin-3 in children with SLD may indicate the role of neuroinflammatory response in the pathogenesis of SLD. Other mechanisms involving galectin-1 and galectin-3 related to learning may play a part in the etiology of SLD.

Galectin-1 promotes gastric cancer peritoneal metastasis through peritoneal fibrosis

BACKGROUND

Peritoneal metastasis is one of the main causes of death in patients with gastric cancer (GC). Galectin-1 regulates various undesirable biological behaviors in GC and may be key in GC peritoneal metastasis.

METHODS

In this study, we elucidated the regulatory role of galectin-1 in GC cell peritoneal metastasis. GC and peritoneal tissues underwent hematoxylin-eosin (HE), immunohistochemical (IHC), and Masson trichrome staining to analyze the difference in galectin-1 expression and peritoneal collagen deposition in different GC clinical stages. The regulatory role of galectin-1 in GC cell adhesion to mesenchymal cells and in collagen expression was determined using HMrSV5 human peritoneal mesothelial cells (HPMCs). Collagen and corresponding mRNA expression were detected with western blotting and reverse transcription PCR, respectively. The promoting effect of galectin-1 on GC peritoneal metastasis was verified in vivo. Collagen deposition and collagen I, collagen III, and fibronectin 1 (FN1) expression in the peritoneum of the animal models were detected by Masson trichrome and IHC staining.

RESULTS

Galectin-1 and collagen deposition in the peritoneal tissues was correlated with GC clinical staging and were positively correlated. Galectin-1 enhanced the ability of GC cells to adhere to the HMrSV5 cells by promoting collagen I, collagen III, and FN1 expression. The in vivo experiments confirmed that galectin-1 promoted GC peritoneal metastasis by promoting peritoneal collagen deposition.

CONCLUSION

Galectin-1-induced peritoneal fibrosis may create a favorable environment for GC cell peritoneal metastasis.

Galectin-1-mediated high NCAPG expression correlates with poor prognosis in gastric cancer

Galectin-1 (Gal1) and non-SMC condensin I complex, subunit G (NCAPG) are associated with metastasis in several malignant tumors. However, their precise roles in gastric cancer (GC) remain uncertain. This study explored the clinical significance and relationship of Gal1 and NCAPG in GC. Gal1 and NCAPG expressions were significantly up-regulated in GC compared to adjacent non-cancerous tissues by immunohistochemistry (IHC) and Western blotting. Besides, methods including stable transfection, quantitative real-time reverse transcription PCR, Western blotting, Matrigel invasion and wound-healing assays in vitro, were also conducted. IHC scores for Gal1 and NCAPG had a positive correlation in GC tissues. High Gal1 or NCAPG expression significantly correlated with poor prognosis in GC, and Gal1 combined with NCAPG had a synergetic effect on the prediction of GC prognosis. Gal1 overexpression in vitro enhanced NCAPG expression, cell migration, and invasion in SGC-7901 and HGC-27 cells. Simultaneous Gal1 overexpression and NCAPG knockdown in GC cells partly rescued the migrative and invasive abilities. Thus, Gal1 promoted GC invasion through increased NCAPG expression. The present study demonstrated the prognostic significance of the combination of Gal1 and NCAPG in GC for the first time.

Galectin-1-dependent ceRNA network in HRMECs revealed its association with retinal neovascularization

BACKGROUND

Retinal neovascularization (RNV) is a leading cause of blindness worldwide. Long non-coding RNA (lncRNA) and competing endogenous RNA (ceRNA) regulatory networks play vital roles in angiogenesis. The RNA-binding protein galectin-1 (Gal-1) participates in pathological RNV in oxygen-induced retinopathy mouse models. However, the molecular associations between Gal-1 and lncRNAs remain unclear. Herein, we aimed to explore the potential mechanism of action of Gal-1 as an RNA-binding protein.

RESULTS

A comprehensive network of Gal-1, ceRNAs, and neovascularization-related genes was constructed based on transcriptome chip data and bioinformatics analysis of human retinal microvascular endothelial cells (HRMECs). We also conducted functional enrichment and pathway enrichment analyses. Fourteen lncRNAs, twenty-nine miRNAs, and eleven differentially expressed angiogenic genes were included in the Gal-1/ceRNA network. Additionally, the expression of six lncRNAs and eleven differentially expressed angiogenic genes were validated by qPCR in HRMECs with or without siLGALS1. Several hub genes, such as NRIR, ZFPM2-AS1, LINC0121, apelin, claudin-5, and C-X-C motif chemokine ligand 10, were found to potentially interact with Gal-1 via the ceRNA axis. Furthermore, Gal-1 may be involved in regulating biological processes related to chemotaxis, chemokine-mediated signaling, the immune response, and the inflammatory response.

CONCLUSIONS

The Gal-1/ceRNA axis identified in this study may play a vital role in RNV. This study provides a foundation for the continued exploration of therapeutic targets and biomarkers associated with RNV.

Galectin-1 promotes angiogenesis and chondrogenesis during antler regeneration

BACKGROUND

Deer antlers are the only known mammalian structure that undergoes full regeneration. In addition, it is peculiar because when growing, it contains vascularized cartilage. The differentiation of antler stem cells (ASCs) into chondrocytes while inducing endochondral extension of blood vessels is necessary to form antler vascularized cartilage. Therefore, antlers provide an unparalleled opportunity to investigate chondrogenesis, angiogenesis, and regenerative medicine. A study found that Galectin-1 (GAL-1), which can be used as a marker in some tumors, is highly expressed in ASCs. This intrigued us to investigate what role GAL-1 could play in antler regeneration.

METHODS

We measured the expression level of GAL-1 in antler tissues and cells by immunohistochemistry, WB and QPCR. We constructed antlerogenic periosteal cells (APCs, one cell type of ASCs) with the GAL-1 gene knocked out (APC^GAL-1-/-) using CRISPR-CAS9 gene editing system. The effect of GAL-1 on angiogenesis was determined by stimulating human umbilical vein endothelial cells (HUVECs) using APC^GAL-1-/- conditioned medium or adding exogenous deer GAL-1 protein. The effect of APC^GAL-1-/- on chondrogenic differentiation was evaluated compared with the APCs under micro-mass culture. The gene expression pattern of APC^GAL-1-/- was analyzed by transcriptome sequencing.

RESULTS

Immunohistochemistry revealed that GAL-1 was widely expressed in the antlerogenic periosteum (AP), pedicle periosteum (PP) and antler growth center. Western blot and qRT-PCR analysis using deer cell lines further supports this result. The proliferation, migration, and tube formation assays of human umbilical vein endothelial cells (HUVECs) showed that the proangiogenic activity of APC^GAL-1-/- medium was significantly decreased (P < 0.05) compared with the APCs medium. The proangiogenic activity of deer GAL-1 protein was further confirmed by adding exogenous deer GAL-1 protein (P < 0.05). The chondrogenic differentiation ability of APC^GAL-1-/- was impeded under micro-mass culture. The terms of GO and KEGG enrichment of the differentially expressed genes (DEGs) of APC^GAL-1-/- showed that down-regulated expression of pathways associated with deer antler angiogenesis, osteogenesis and stem cell pluripotency, such as the PI3K-AKT signaling pathway, signaling pathways regulating pluripotency of stem cells and TGF-β signaling pathway.

CONCLUSIONS

Deer GAL-1, has strong angiogenic activity, is widely and highly expressed in deer antler. The APCs can induce angiogenesis by secreting GAL-1. The knockout of GAL-1 gene of APCs damaged its ability to induce angiogenesis and differentiate into chondrocytes. This ability is crucial to the formation of deer antler vascularized cartilage. Moreover, Deer antlers offer a unique model to explore explore how angiogenesis at high levels of GAL-1 expression can be elegantly regulated without becoming cancerous.