HH1-1, a novel Galectin-3 inhibitor, exerts anti-pancreatic cancer activity by blocking Galectin-3/EGFR/AKT/FOXO3 signaling pathway

RN0D, a galactoglucan from Panax notoginseng flower induces cancer cell death via PINK1/Parkin mitophagy

Metabolic alterations within mitochondria, encompassing processes such as autophagy and energy metabolism, play a pivotal role in facilitating the swift proliferation, invasion, and metastasis of cancer cells. Despite this, there is a scarcity of currently available medications with proven anticancer efficacy through the modulation of mitochondrial dysfunction in a clinical setting. Here, we introduce the structural characteristics of RN0D, a galactoglucan isolated and purified from Panax notoginseng flowers, mainly composed of β-1,4-galactan and β-1,3/1,6-glucan. RN0D demonstrates the capacity to induce mitochondrial impairment in cancer cells, leading to the accumulation of reactive oxygen species, initiation of mitophagy, and reduction in both mitochondrial number and size. This sequence of events ultimately results in the inhibition of mitochondrial and glycolytic bioenergetics, culminating in the demise of cancer cells due to adenosine triphosphate (ATP) deprivation. Notably, the observed bioactivity is attributed to RN0D's direct targeting of Galectin-3, as affirmed by surface plasmon resonance studies. Furthermore, RN0D is identified as an activator of the PTEN-induced kinase 1 (PINK1)/Parkin pathway, ultimately instigating cytotoxic mitophagy in tumor cells. This comprehensive study substantiates the rationale for advancing RN0D as a potentially efficacious anticancer therapeutic.

Modified Citrus Pectin (MCP) Confers a Renoprotective Effect on Early-Stage Nephropathy in Type-2 Diabetic Mice

Diabetic nephropathy (DN) is a significant global health concern with a high morbidity rate. Accumulating evidence reveals that Galectin-3 (Gal-3), a β-galactoside-binding lectin, is a biomarker in kidney diseases. Our study aimed to assess the advantageous impacts of modified citrus pectin (MCP) as an alternative therapeutic strategy for the initial and ongoing progression of DN in mice with type 2 diabetes mellitus (T2DM). The animal model has been split into four groups: control group, T2DM group (mice received intraperitoneal injections of nicotinamide (NA) and streptozotocin (STZ), T2DM+MCP group (mice received 100 mg/kg/day MCP following T2DM induction), and MCP group (mice received 100 mg/kg/day). After 4 weeks, kidney weight, blood glucose level, serum kidney function tests, histopathological structure alterations, oxidative stress, inflammation, apoptosis, and fibrosis parameters were determined in renal tissues. Our findings demonstrated that MCP treatment reduced blood glucose levels, renal histological damage, and restored kidney weight and kidney function tests. Additionally, MCP reduced malondialdehyde level and restored glutathione level, and catalase activity. MCP demonstrated a notable reduction in inflammatory and apoptosis mediators TNF-α, iNOS, TGF-βRII and caspase-3. Overall, MCP could alleviate renal injury in an experimental model of DN by suppressing renal oxidative stress, inflammation, fibrosis, and apoptosis mediators.

XQZ3, a Chlorella pyrenoidosa polysaccharide suppresses cancer progression by restraining mitochondrial bioenergetics via HSP90/AKT signaling pathway

The mitochondria are known to exert significant influence on various aspects of cancer cell physiology. The suppression of mitochondrial function represents a novel avenue for the advancement of anti-cancer pharmaceuticals. The heat shock protein HSP90 functions as a versatile regulator of mitochondrial metabolism in cancer cells, rendering as a promising target for anticancer interventions. In this work, a novel acid polysaccharide named as XQZ3 was extracted from Chlorella pyrenoidosa and purified by DEAE-cellulose and gel-filtration chromatography. The structural characteristic of XQZ3 was evaluated by monosaccharides composition, methylation analysis, TEM, FT-IR, and 2D-NMR. It was found that XQZ3 with a molecular weight of 29.13 kDa was a complex branched polysaccharide with a backbone mainly composed of galactose and mannose. It exhibited good antitumor activity in vitro and in vivo by patient-derived 3D organoid models and patient-derived xenografts models. The mechanistic investigations revealed that XQZ3 specifically interacted with HSP90, impeding the activation of the HSP90/AKT/mTOR signaling cascade. This, in turn, led to the induction of mitochondrial dysfunction, autophagy, and apoptosis, ultimately resulting in the demise of cancer cells due to nutrient deprivation. This study offers a comprehensive theoretical foundation for the advancement of XQZ3, a novel polysaccharide inhibitor targeting HSP90, with potential as an effective therapeutic agent against cancer.

Interplay in galectin expression predicts patient outcomes in a spatially restricted manner in PDAC

BACKGROUND

Galectins (Gal's) are a family of carbohydrate-binding proteins that are known to support the tumour microenvironment through their immunosuppressive activity and ability to promote metastasis. As such they are attractive therapeutic targets, but little is known about the cellular expression pattern of galectins within the tumour and its neighbouring stromal microenvironment. Here we investigated the cellular expression pattern of Gals within pancreatic ductal adenocarcinoma (PDAC).

METHODS

Galectin gene and protein expression were analysed by scRNAseq (n=4) and immunofluorescence imaging (n=19) in fibroblasts and epithelial cells of pancreatic biopsies from PDAC patients. Galectin surface expression was also assessed on tumour adjacent normal fibroblasts and cancer associated primary fibroblasts from PDAC biopsies using flow cytometry.

RESULTS

scRNAseq revealed higher Gal-1 expression in fibroblasts and higher Gal-3 and -4 expression in epithelial cells. Both podoplanin (PDPN+, stromal/fibroblast) cells and EpCAM+ epithelial cells expressed Gal-1 protein, with highest expression seen in the stromal compartment. By contrast, significantly more Gal-3 and -4 protein was expressed in ductal cells expressing either EpCAM or PDPN, when compared to the stroma. Ductal Gal-4 cellular expression negatively correlated with ductal Gal-1, but not Gal-3 expression. Higher ductal cellular expression of Gal-1 correlated with smaller tumour size and better patient survival.

CONCLUSIONS

In summary, the intricate interplay and cell-specific expression patterns of galectins within the PDAC tissue, particularly the inverse correlation between Gal-1 and Gal-4 in ducts and its significant association with patient survival, highlights the complex molecular landscape underlying PDAC and provides valuable insights for future therapeutic interventions.

Recent chemical synthesis of plant polysaccharides

Here, chemical syntheses of long, branched and complex glycans over 10-mer from plants are summarized, which highlights amylopectin 20-mer from starch, 17-mer from carthamus tinctorius, α-glucan 30-mer from Longan, 19-mer from psidium guajava and 11-mer from dendrobium huoshanense. The glycans assembly strategies, protecting groups utilization and glycosylation methods discussed here will inspire the efficient synthesis of diverse complex glycans with many 1,2-cis glycosidic linkages.

Unveiling the potential of galectin-3 as a diagnostic biomarker for pancreatic cancer: a review

Early detection of pancreatic cancer is crucial for improving patient outcomes, and identifying reliable biomarkers is a critical research area in this field. Galectin-3 (Gal-3) is a promising candidate for utilisation as a diagnostic biomarker in early-stage pancreatic cancer. This review aims to explore the potential of Gal-3 in pancreatic cancer diagnosis and its implications for precision medicine. Rigorous validation studies are essential to establish the clinical utility of Gal-3, including large-scale investigations to assess its sensitivity, specificity, and predictive value. Combining Gal-3 with existing biomarkers and advanced imaging techniques may enhance the accuracy of early detection. Moreover, Gal-3 holds promise for risk stratification, enabling the identification of high-risk individuals who could benefit from intensified surveillance and early interventions. However, challenges in standardised testing protocols, establishing reference ranges, assay reliability, workflow integration, cost-effectiveness, and healthcare provider education must be addressed for successful implementation. Despite these challenges, Gal-3 presents significant implications for precision medicine in pancreatic cancer management. By unravelling its potential and overcoming the hurdles, Gal-3 could revolutionise early detection, risk stratification, and personalised approaches in pancreatic cancer care. Collaborative efforts and continued research will be crucial in harnessing the full potential of Gal-3 as a diagnostic biomarker for early-stage pancreatic cancer.

Galectin-3's Complex Interactions in Pancreatic Ductal Adenocarcinoma: From Cellular Signaling to Therapeutic Potential

Galectin-3 (Gal-3) plays a multifaceted role in the development, progression, and prognosis of pancreatic ductal adenocarcinoma (PDAC). This review offers a comprehensive examination of its expression in PDAC, its interaction with various immune cells, signaling pathways, effects on apoptosis, and therapeutic resistance. Additionally, the prognostic significance of serum levels of Gal-3 is discussed, providing insights into its potential utilization as a biomarker. Critical analysis is also extended to the inhibitors of Gal-3 and their potential therapeutic applications in PDAC, offering new avenues for targeted treatments. The intricate nature of Gal-3's role in PDAC reveals a complex landscape that demands a nuanced understanding for potential therapeutic interventions and monitoring.

Therapeutic efficacy and underlying mechanisms of Gastrodia elata polysaccharides on dextran sulfate sodium-induced inflammatory bowel disease in mice: Modulation of the gut microbiota and improvement of metabolic disorders

Inflammatory bowel disease (IBD) is a chronic inflammatory gastrointestinal disease, and an imbalance in the gut microbiota is a critical factor in its development. Gastrodia elata (G. elata), an Orchidaceae plant, is recognized for its nutritional and medicinal value. Studies have shown that G. elata polysaccharides (GBP) have anti-inflammatory properties that may ameliorate IBD. However, the therapeutic effects of GBP on gut microbiota metabolism remain unknown. Therefore, we aimed to examine the therapeutic potential of G. elata extract and GBP in dextran sulfate sodium (DSS)-induced IBD mice. GBP demonstrated the best therapeutic effect by reducing IBD symptoms in mice to the greatest extent. Administering GBP resulted in significant increases in the relative abundances of bacteria with potential anti-inflammatory effects, such as Ligilactobacillus and Alloprevotella, and decreases in the levels of bacteria associated with proinflammatory responses, such as Bacteroides and Escherichia-Shigella. Furthermore, 36 significant differential metabolites between the model and GBP groups were identified in feces, which were mainly enriched in amino acid metabolism, including tryptophan and cysteine, vitamin B6 metabolism and steroid hormone biosynthesis. Consequently, investigating the metabolic regulation of the gut microbiota is a promising approach to evaluate the therapeutic effect of GBP on IBD.

Catalpol Prevents Glomerular Angiogenesis Induced by Advanced Glycation End Products via Inhibiting Galectin-3

OBJECTIVE

The main characteristics of diabetic nephropathy (DN) at the early stage are abnormal angiogenesis of glomerular endothelial cells (GECs) and macrophage infiltration. Galectin-3 plays a pivotal role in the pathogenesis of DN via binding with its ligand, advanced glycation end products (AGEs). Catalpol, an iridoid glucoside extracted from Rehmannia glutinosa, has been found to ameliorate vascular inflammation, reduce endothelial permeability, and protect against endothelial damage in diabetic milieu. However, little is known about whether catalpol could exert an anti-angiogenesis and anti-inflammation effect induced by AGEs.

METHODS

Mouse GECs (mGECs) and RAW 264.7 macrophages were treated with different concentrations of AGEs (0, 50, 100, 200 and 400 µg/mL) for different time (0, 6, 12, 24 and 48 h) to determine the optimal concentration of AGEs and treatment time. Cells were treated with catalpol (10 µmol/L), GB1107 (1 µmol/L, galectin-3 inhibitor), PX-478 (50 µmol/L, HIF-1α inhibitor), adenovirus-green fluorescent protein (Ad-GFP) [3×107 plaque-forming unit (PFU)/mL] or Ad-galectin-3-GFP (2×108 PFU/mL), which was followed by incubation with 50 µg/mL AGEs. The levels of galectin-3, vascular endothelial growth factor A (VEGFA) and pro-angiogenic factors angiopoietin-1 (Ang-1), angiopoietin-2 (Ang-2), tunica interna endothelial cell kinase-2 (Tie-2) were detected by enzymelinked immunosorbent assay (ELISA). Cell counting kit-8 (CCK-8) assay was used to evaluate the proliferation of these cells. The expression levels of galectin-3, vascular endothelial growth factor receptor 1 (VEGFR1), VEGFR2, and hypoxia-inducible factor-1α (HIF-1α) in mGECs and those of galectin-3 and HIF-1α in RAW 264.7 macrophages were detected by Western blotting and immunofluorescence (IF) staining. The rat DN model was established. Catalpol (100 mg/kg) or GB1107 (10 mg/kg) was administered intragastrically once a day for 12 weeks. Ad-galectin-3-GFP (6×107 PFU/mL, 0.5 mL) or Ad-GFP (6×106 PFU/mL, 0.5 mL) was injected into the tail vein of rats 48 h before the sacrifice of the animals. The expression of galectin-3, VEGFR1, VEGFR2, and HIF-1α in renal cortices was analyzed by Western blotting. The expression of galectin-3, F4/80 (a macrophage biomarker), and CD34 (an endothelium biomarker) in renal cortices was detected by IF staining, and collagen accumulation by Masson staining.

RESULTS

The expression levels of galectin-3 and VEGFA were significantly higher in mGECs and RAW 264.7 macrophages treated with 50 µg/mL AGEs for 48 h than those in untreated cells. Catalpol and GB1107 could block the AGEs-induced proliferation of mGECs and RAW 264.7 macrophages. Over-expression of galectin-3 was found to reduce the inhibitory effect of catalpol on the proliferation of cells. Catalpol could significantly decrease the levels of Ang-1, Ang-2 and Tie-2 released by AGEs-treated mGECs, which could be reversed by over-expression of galectin-3. Catalpol could significantly inhibit AGEs-induced expression of galectin-3, HIF-1α, VEGFR1, and VEGFR2 in mGECs. The inhibitory effect of catalpol on galectin-3 in AGEs-treated mGECs was impaired by PX-478. Moreover, catalpol attenuated the AGEs-activated HIF-1α/galectin-3 pathway in RAW 264.7 macrophages, which was weakened by PX-478. Additionally, catalpol significantly inhibited the expression of galectin-3, macrophage infiltration, collagen accumulation, and angiogenesis in the kidney of diabetic rats. Over-expression of galectin-3 could antagonize these inhibitory effects of catalpol.

CONCLUSION

Catalpol prevented the angiogenesis of mGECs and macrophage proliferation via inhibiting galectin-3. It could prevent the progression of diabetes-induced renal damage.

Plant type II arabinogalactan: Structural features and modification to increase functionality

Type II arabinogalactans (AGs) are a highly diverse class of plant polysaccharides generally encountered as the carbohydrate moieties of certain extracellular proteoglycans, the so-called arabinogalactan-proteins (AGPs), which are found on plasma membranes and in cell walls. The basic structure of type II AG is a 1,3-β-D-galactan main chain with 1,6-β-D-galactan side chains. The side chains are further decorated with other sugars such as α-l-arabinose and β-d-glucuronic acid. In addition, AGs with 1,6-β-D-galactan as the main chain, which are designated as 'type II related AG' in this review, can also be found in several plants. Due to their diverse and heterogenous features, the determination of carbohydrate structures of type II and type II related AGs is not easy. On the other hand, these complex AGs are scientifically and commercially attractive materials whose structures can be modified by chemical and biochemical approaches for specific purposes. In the current review, what is known about the chemical structures of type II and type II related AGs from different plant sources is outlined. After that, structural analysis techniques are considered and compared. Finally, structural modifications that enhance or alter functionality are highlighted.

Galectins and galectin-mediated autophagy regulation: new insights into targeted cancer therapy

Galectins are animal lectins with specific affinity for galactosides via the conserved carbohydrate recognition domains. Increasing studies recently have identified critical roles of galectin family members in tumor progression. Abnormal expression of galectins contributes to the proliferation, metastasis, epithelial-mesenchymal transformation (EMT), immunosuppression, radio-resistance and chemoresistance in various cancers, which has attracted cumulative clinical interest in galectin-based cancer treatment. Galectin family members have been reported to participate in autophagy regulation under physiological conditions and in non-tumoral diseases, and implication of galectins in multiple processes of carcinogenesis also involves regulation of autophagy, however, the relationship between galectins, autophagy and cancer remains largely unclear. In this review, we introduce the structure and function of galectins at the molecular level, summarize their engagements in autophagy and cancer progression, and also highlight the regulation of autophagy by galectins in cancer as well as the therapeutic potentials of galectin and autophagy-based strategies. Elaborating on the mechanism of galectin-regulated autophagy in cancers will accelerate the exploitation of galectins-autophagy targeted therapies in treatment for cancer.

Polysaccharides from Chinese materia medica: Perspective towards cancer management

Cancer has always been a focus of global attention, and the difficulty of treatment and poor prognosis have always plagued humanity. Conventional chemotherapeutics and treatment with synthetic disciplines will cause adverse side effects and drug resistance. Therefore, searching for a safe, valid, and clinically effective drug is necessary. At present, some natural compounds have proved to have the potential to fight cancer. Polysaccharides obtained from Chinese materia medica are good anti-cancer ingredients. Polysaccharides are macromolecular compounds of equal or distinct monosaccharides with an α- or β-glycosidic bonds. The anti-cancer activity has been fully demonstrated in vivo and in vitro. However, Chinese materia medica polysaccharides are only used as adjuvant therapy for cancer-related diseases. Hence, this review mainly discusses the chemical composition, biological activity, absorption in vivo, and clinical application of Chinese materia medica polysaccharides. Also, we discussed the anti-cancer mechanism. We also discussed the current research's limitations on treating cancer with Chinese materia medica polysaccharides and insights into future research.

Galectins Are Central Mediators of Immune Escape in Pancreatic Ductal Adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal cancers and is highly immune tolerant. Although there is immune cell infiltration in PDAC tissues, most of the immune cells do not function properly and, therefore, the prognosis of PDAC is very poor. Galectins are carbohydrate-binding proteins that are intimately involved in the proliferation and metastasis of tumor cells and, in particular, play a crucial role in the immune evasion of tumor cells. Galectins induce abnormal functions and reduce numbers of tumor-associated macrophages (TAM), natural killer cells (NK), T cells and B cells. It further promotes fibrosis of tissues surrounding PDAC, enhances local cellular metabolism, and ultimately constructs tumor immune privileged areas to induce immune evasion behavior of tumor cells. Here, we summarize the respective mechanisms of action played by different Galectins in the process of immune escape from PDAC, focusing on the mechanism of action of Galectin-1. Galectins cause imbalance between tumor immunity and anti-tumor immunity by coordinating the function and number of immune cells, which leads to the development and progression of PDAC.

Galectin-3 in Microglia-Mediated Neuroinflammation: Implications for Central Nervous System Diseases

Microglial activation is one of the common hallmarks shared by various central nervous system (CNS) diseases. Based on surrounding circumstances, activated microglia play either detrimental or neuroprotective effects. Galectin-3 (Gal-3), a group of β-galactoside-binding proteins, has been cumulatively revealed to be a crucial biomarker for microglial activation after injuries or diseases. In consideration of the important role of Gal-3 in the regulation of microglial activation, it might be a potential target for the treatment of CNS diseases. Recently, Gal-3 expression has been extensively investigated in numerous pathological processes as a mediator of neuroinflammation, as well as in cell proliferation. However, the underlying mechanisms of Gal-3 involved in microgliamediated neuroinflammation in various CNS diseases remain to be further investigated. Moreover, several clinical studies support that the levels of Gal-3 are increased in the serum or cerebrospinal fluid of patients with CNS diseases. Thus, we summarized the roles and underlying mechanisms of Gal-3 in activated microglia, thus providing a better insight into its complexity expression pattern, and contrasting functions in CNS diseases.

Convergent Synthesis and Anti-Pancreatic Cancer Cell Growth Activity of a Highly Branched Heptadecasaccharide from Carthamus tinctorius

Bioactive polysaccharides from natural resources target various biological processes and are increasingly used as potential target molecules for drug development. However, the accessibility of branched and long complex polysaccharide active domains with well-defined structures remains a major challenge. Herein we describe an efficient first total synthesis of a highly branched heptadecasaccharide moiety of the native bioactive galectin-3-targeting polysaccharide from Carthamus tinctorius L. as well as shorter fragments of the heptadecasaccharide. The key feature of the approach is that a photo-assisted convergent [6+4+7] one-pot coupling strategy enables rapid assembly of the heptadecasaccharide, whereby a photoremovable o-nitrobenzyl protecting group is used to generate the corresponding acceptor for glycosylation in situ upon ultraviolet radiation. Biological activity tests suggest that the heptadecasaccharide can target galectin-3 and inhibit pancreatic cancer cell growth.

An oleanolic acid derivative, K73-03, inhibits pancreatic cancer cells proliferation in vitro and in vivo via blocking EGFR/Akt pathway

Oleanolic acid (OA) and its derivatives show potent anticancer function. Pancreatic cancer (PC) is the fourth core motive of cancer-related deaths worldwide. Epidermal growth factor receptor (EGFR) has been implicated in PC and has been validated as a therapeutic target. Our study demonstrated that K73-03, an OA derivative, was identified as a potent inhibitor of EGFR by using reverse pharmacophore screening and molecular dynamics simulation assays. Moreover, Western blot analysis showed that K73-03 markedly suppressed the levels of phosphorylated-EGFR (p-EGFR) and phosphorylated-Akt (p-Akt). The inhibitory effect of K73-03 on PC cells was assessed in vitro and in vivo. Mechanistically, K73-03 effectively inhibited the cell proliferation of PC cells, and induced apoptosis and autophagy of ASPC-1 cells in a dose-dependent manner. Additionally, pretreatment with chloroquine, an autophagy inhibitor, significantly inhibited K73-03-induced autophagy and enhanced K73-03-induced apoptotic cell death. K73-03 also strongly repressed ASPC-1 cells xenograft growth in vivo. Thus, all these findings provided new clues about OA analog K73-03 as an effective anticancer agent targeted EGFR against ASPC-1 cells, it is worth further evaluation in the future.

Antibody-mediated blockade for galectin-3 binding protein in tumor secretome abrogates PDAC metastasis

The major challenges in pancreatic ductal adenocarcinoma (PDAC) management are local or distant metastasis and limited targeted therapeutics to prevent it. To identify a druggable target in tumor secretome and to explore its therapeutic intervention, we performed a liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based proteomic analysis of tumors obtained from a patient-derived xenograft model of PDAC. Galectin-3 binding protein (Gal-3BP) is identified as a highly secreted protein, and its overexpression is further validated in multiple PDAC tumors and primary cells. Knockdown and exogenous treatment of Gal-3BP showed that it is required for PDAC cell proliferation, migration, and invasion. Mechanistically, we revealed that Gal-3BP enhances galectin-3-mediated epidermal growth factor receptor signaling, leading to increased cMyc and epithelial-mesenchymal transition. To explore the clinical impact of these findings, two antibody clones were developed, and they profoundly abrogated the metastasis of PDAC cells in vivo. Altogether, our data demonstrate that Gal-3BP is an important therapeutic target in PDAC, and we propose its blockade by antibody as a therapeutic option for suppressing PDAC metastasis.

MG-Pe: A Novel Galectin-3 Ligand with Antimelanoma Properties and Adjuvant Effects to Dacarbazine

Melanoma is a highly metastatic and rapidly progressing cancer, a leading cause of mortality among skin cancers. The melanoma microenvironment, formed from the activity of malignant cells on the extracellular matrix and the recruitment of immune cells, plays an active role in the development of drug resistance and tumor recurrence, which are clinical challenges in cancer treatment. These tumoral metabolic processes are affected by proteins, including Galectin-3 (Gal-3), which is extensively involved in cancer development. Previously, we characterized a partially methylated mannogalactan (MG-Pe) with antimelanoma activities. In vivo models of melanoma were used to observe MG-Pe effects in survival, spontaneous, and experimental metastases and in tissue oxidative stress. Analytical assays for the molecular interaction of MG-Pe and Gal-3 were performed using a quartz crystal microbalance, atomic force microscopy, and contact angle tensiometer. MG-Pe exhibits an additive effect when administered together with the chemotherapeutic agent dacarbazine, leading to increased survival of treated mice, metastases reduction, and the modulation of oxidative stress. MG-Pe binds to galectin-3. Furthermore, MG-Pe antitumor effects were substantially reduced in Gal-3/KO mice. Our results showed that the novel Gal-3 ligand, MG-Pe, has both antitumor and antimetastatic effects, alone or in combination with chemotherapy.

Th1 immune maturation effects of

Nocardia rubra cell-wall skeleton (Nr-CWS) is reported as an external immunotherapeutic enhancer with the advantage of antitumor effect on human cancers. However, the immune regulatory role of Nr-CWS is not fully illustrated. We studied mouse CD4+ T lymphocytes isolated from mice spleen were induced by Nr-CWS and observed that the differentiation of Th1 CD4+ T cells and the cytokines of IL-2, TNF-α, IFN-γ were all enhanced by Nr-CWS. Furthermore, RNA sequencing was conducted to investigate the different mRNA profiling induced by Nr-CWS. We observed that paired box 8 (PAX8) was significantly up-regulated in Nr-CWS-treated Th1 cells compared to control. As a transcription factor, chromatin immunoprecipitation sequencing was carried out to study the genome-wide distribution of PAX8. Interestingly, we found that the binding domain of PAX8 was elevated by Nr-CWS, and the target genes associated with these binding sites showed a positive correlation between their transcription and PAX8 binding strength. Finally, we determined that Nr-CWS could enhance the activity of the PI3 K/Akt signaling pathway. Akt agonist could mimic the effect of Nr-CWS for PAX8 up-regulation, while Akt inhibitor compromised the expression of PAX8. Taken together, we determined a novel role of Nr-CWS in boosting the activity of Th1 maturation via the PI3 K/Akt/PAX8 axis.

Pancreatic cancer-associated diabetes mellitus is characterized by reduced β-cell secretory capacity, rather than insulin resistance

AIMS

The early distinction of pancreatic cancer associated diabetes (PaCDM) in patients with elderly diabetes is critical. However, PaCDM and type 2 diabetes mellitus (T2DM) remain indistinguishable. We aim to address the differences between the pancreatic and gut endocrine hormones of patients with PaCDM and T2DM.

METHODS

A total of 44 participants underwent mixed meal tolerance test (MMTT). Fasting and postprandial concentrations of insulin, C-peptide, glucagon, pancreatic polypeptide (PP), glucagon-like peptide-1 (GLP-1), and gastric inhibitory peptide (GIP) were measured. Insulin sensitivity and secretion indices were calculated. One-way ANOVA with post-hoc analysis was used for statistical analysis.

RESULTS

Insulin and C-peptide responses to MMTT were blunted in PaCDM patients compared with T2DM. Baseline concentrations and AUCs differed. PaCDM patients showed lower insulin secretion capacity but better insulin sensitivity than T2DM patients. The peak concentration and AUC of PP in T2DM group were higher than healthy controls, but in accordance with PaCDM. PaCDM patients presented lower baseline GLP-1 concentration than T2DM patients. No between-group differences were found for glucagon and GIP.

CONCLUSIONS

PaCDM patients had a lower baseline and postprandial insulin and C-peptide secretion than T2DM patients. Reduced insulin secretion and improved peripheral sensitivity were found in PaCDM patients compared with T2DM.

Human umbilical cord mesenchymal stem cell-derived exosomes carrying hsa-miRNA-128-3p suppress pancreatic ductal cell carcinoma by inhibiting Galectin-3

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is one of the most fatal malignant tumors of the digestive system. Many patients are diagnosed at an advanced stage and lose eligibility for surgery. Moreover, there are few effective methods for treating pancreatic ductal cell carcinoma. Increasing attention has been given to microRNAs (miRNAs) and their regulatory roles in tumor progression. In this study, we investigated the effects of exosomes extracted from human umbilical cord mesenchymal stem cells (HUCMSCs) carrying hsa-miRNA-128-3p on pancreatic cancer cells.

METHODS

Based on existing experimental and database information, we selected Galectin-3, which is associated with pancreatic cancer, and the corresponding upstream hsa-miRNA-128-3p. We extracted HUCMSCs from a fresh umbilical cord, hsa-miRNA-128-3p was transfected into HUCMSCs, and exosomes containing hsa-miRNA-128-3p were extracted and collected. The effect of exosomes rich in hsa-miRNA-128-3p on pancreatic cancer cells was analyzed.

RESULTS

The expression of Galectin-3 in normal pancreatic duct epithelial cells was significantly lower than that in PDAC cell lines. We successfully extracted HUCMSCs from the umbilical cord and transfected hsa-miRNA-128-3p into HUCMSCs. Then we demonstrated that HUCMSC-derived exosomes with hsa-miRNA-128-3p could suppress the proliferation, invasion, and migration of PANC-1 cells in vitro by targeting Galectin-3.

CONCLUSION

Hsa-miRNA-128-3p could be considered as a potential therapy for pancreatic cancer. We provided a new idea for targeted therapy of PDAC.

Comparative transcriptome analysis of human and murine choroidal neovascularization identifies fibroblast growth factor inducible-14 as phylogenetically conserved mediator of neovascular age-related macular degeneration

BACKGROUND

Visual outcome of patients with neovascular age-related macular degeneration has significantly improved during the last years following the introduction of anti-vascular endothelial growth factor (VEGF) therapy. However, about one third of patients show persistent exudation and decreasing visual acuity despite recurrent anti-VEGF treatment, which implies a role of other, still unknown proangiogenic mediators.

METHODS

The present study applied transcriptional profiling of human and mouse (C57BL/6J wildtype) choroidal neovascularization (CNV) membranes each with reference to healthy control tissue to identify yet unrecognized mediators of CNV formation. Key factors were further investigated by immunohistochemistry as well as by intravitreal inhibition experiments and multiplex protein assays in the laser-induced CNV mouse model.

FINDINGS

Transcriptional profiles of CNV membranes were characterized by enhanced activation of blood vessel development, cytoskeletal organization, and cytokine production, with angiogenesis and wound healing processes predominating in humans and activation of immune processes in mice. Besides several species-specific factors, 95 phylogenetically conserved CNV-associated genes were detected, among which fibroblast growth factor inducible-14 (FN14), a member of the tumor necrosis factor (TNF) receptor family, was identified as a key player of CNV formation. Blocking the pathway by intravitreal injection of a FN14 decoy receptor modulated the cytokine profile - most notably IL-6 - and led to a significant reduction of CNV size in vivo.

INTERPRETATION

This study characterizes the transcriptome of human and mouse CNV membranes in an unprejudiced manner and identifies FN14 as a phylogenetically conserved mediator of CNV formation and a promising new therapeutic target for neovascular AMD.

FUNDING

This study was funded by the Helmut Ecker Foundation and the Volker Homann Foundation.

Natural Products: A Promising Therapeutics for Targeting Tumor Angiogenesis

Tumor-associated angiogenesis is a key target for anti-cancer therapy. The imbalance between pro-angiogenic and anti-angiogenic signals elicited by tumor cells or tumor microenvironment always results in activating "angiogenic switch". Tumor angiogenesis functions in multi-aspects of tumor biology, including endothelial cell apoptosis, tumor metastasis, and cancer stem cell proliferation. Numerous studies have indicated the important roles of inexpensive and less toxic natural products in targeting tumor angiogenesis-associated cytokines and apoptotic signaling pathways. Our current knowledge of tumor angiogenesis is based mainly on experiments performed on cells and animals, so we summarized the well-established models for angiogenesis both in vitro and in vivo. In this review, we classified and summarized the anti-angiogenic natural agents (Polyphenols, Polysaccharides, Alkaloids, Terpenoids, Saponins) in targeting various tumor types according to their chemical structures at present, and discussed the mechanistic principles of these natural products on regulating angiogenesis-associated cytokines and apoptotic signaling pathways. This review is to help understanding the recent progress of natural product research for drug development on anti-tumor angiogenesis.

Extraction, Structures, Bioactivities and Structure-Function Analysis of the Polysaccharides From Safflower (Carthamus tinctorius L.)

Safflower (Carthamus tinctorius L.) is a herbal plant with a long history of clinical application worldwide, such as coronary heart disease, hypertension, dysmenorrhea and amenorrhea. It is also extensively used as an important oilseed plant for hundreds of years in some countries, like China, India, Mexico and the United States. Therefore, safflower is believed as a crop with dual values of medicine and economy as well. Safflower polysaccharides (SPS), from the plant, are believed as one of the most important biologically active components with multiple pharmacological properties, including anti-tumor, immune regulation, anti-oxidation, and anti-cerebral ischemia reperfusion injury effects. The polysaccharides, from bee pollen of safflower, named PBPC, also attract the attention of researchers because of their particular origin and bioactivities. Although the extraction, purification, structure and biological activities of SPS and PBPC have been studied for decades, there is not any available review both concerning SPS and PBPC. In this condition, this paper aims to systematically review the research progress in extraction, purification, structural characteristics, and bioactivities of SPS and PBPC, and provide basis for the in-depth study about their structure-bioactivity relationship. It will serve as a methodological outline for further research in fields of new drug discovery and clinical application of SPS or PBPC, and simultaneously remind us of unresolved problems noted in the polysaccharide research.

Novel Galectin-3 Roles in Neurogenesis, Inflammation and Neurological Diseases

Galectin-3 (Gal-3) is an evolutionarily conserved and multifunctional protein that drives inflammation in disease. Gal-3's role in the central nervous system has been less studied than in the immune system. However, recent studies show it exacerbates Alzheimer's disease and is upregulated in a large variety of brain injuries, while loss of Gal-3 function can diminish symptoms of neurodegenerative diseases such as Alzheimer's. Several novel molecular pathways for Gal-3 were recently uncovered. It is a natural ligand for TREM2 (triggering receptor expressed on myeloid cells), TLR4 (Toll-like receptor 4), and IR (insulin receptor). Gal-3 regulates a number of pathways including stimulation of bone morphogenetic protein (BMP) signaling and modulating Wnt signalling in a context-dependent manner. Gal-3 typically acts in pathology but is now known to affect subventricular zone (SVZ) neurogenesis and gliogenesis in the healthy brain. Despite its myriad interactors, Gal-3 has surprisingly specific and important functions in regulating SVZ neurogenesis in disease. Gal-1, a similar lectin often co-expressed with Gal-3, also has profound effects on brain pathology and adult neurogenesis. Remarkably, Gal-3's carbohydrate recognition domain bears structural similarity to the SARS-CoV-2 virus spike protein necessary for cell entry. Gal-3 can be targeted pharmacologically and is a valid target for several diseases involving brain inflammation. The wealth of molecular pathways now known further suggest its modulation could be therapeutically useful.

Galectins in Cancer and the Microenvironment: Functional Roles, Therapeutic Developments, and Perspectives

Changes in cell growth and metabolism are affected by the surrounding environmental factors to adapt to the cell’s most appropriate growth model. However, abnormal cell metabolism is correlated with the occurrence of many diseases and is accompanied by changes in galectin (Gal) performance. Gals were found to be some of the master regulators of cell–cell interactions that reconstruct the microenvironment, and disordered expression of Gals is associated with multiple human metabolic-related diseases including cancer development. Cancer cells can interact with surrounding cells through Gals to create more suitable conditions that promote cancer cell aggressiveness. In this review, we organize the current understanding of Gals in a systematic way to dissect Gals’ effect on human disease, including how Gals’ dysregulated expression affects the tumor microenvironment’s metabolism and elucidating the mechanisms involved in Gal-mediated diseases. This information may shed light on a more precise understanding of how Gals regulate cell biology and facilitate the development of more effective therapeutic strategies for cancer treatment by targeting the Gal family.

MASTL regulates EGFR signaling to impact pancreatic cancer progression

Pancreatic cancer (PC) remains a major cause of cancer-related deaths primarily due to its inherent potential of therapy resistance. Checkpoint inhibitors have emerged as promising anti-cancer agents when used in combination with conventional anti-cancer therapies. Recent studies have highlighted a critical role of the Greatwall kinase (microtubule-associated serine/threonine-protein kinase-like (MASTL)) in promoting oncogenic malignancy and resistance to anti-cancer therapies; however, its role in PC remains unknown. Based on a comprehensive investigation involving PC patient samples, murine models of PC progression (Kras;PdxCre-KC and Kras;p53;PdxCre-KPC), and loss and gain of function studies, we report a previously undescribed critical role of MASTL in promoting cancer malignancy and therapy resistance. Mechanistically, MASTL promotes PC by modulating the epidermal growth factor receptor protein stability and, thereupon, kinase signaling. We further demonstrate that combinatorial therapy targeting MASTL promotes the efficacy of the cell-killing effects of Gemcitabine using both genetic and pharmacological inhibitions. Taken together, this study identifies a key role of MASTL in promoting PC progression and its utility as a novel target in promoting sensitivity to the anti-PC therapies.

The structure elucidation of novel arabinogalactan LRP1-S2 against pancreatic cancer cells growth in vitro and in vivo

The fruit of Lycium ruthenicum Murr is used as traditional medicine and functional food. Previously we reported that one RG-I pectin from this fruit might inhibit pancreatic cancer cells growth. We further hypothesized that there might be other type of polysaccharides in this fruit also have anti-tumor effect. Here, we showed novel structure of a homogeneous polysaccharide named LRP1-S2 from this fruit and its anti-pancreatic cancer effect. Structure analyses suggested that LRP1-S2 was a novel arabinogalactan with the molecular weight (Mw) of 17.0 kDa. Bioactivity test showed that LRP1-S2 might attenuate the proliferation of pancreatic cancer cells in vitro and in vivo without significant cytotoxicity to normal pancreatic HPDE6-C7 cells and LO2 liver cells. Mechanism study indicated that it might induce apoptosis of BxPC-3 by inactivating P38 MAPK/NF-κB and GSK-3β/β-Catenin signaling pathways. These results suggested that LRP1-S2 could be a potential anti-tumor leading compound for functional food and new drug development. CHEMICAL COMPOUNDS: arabinogalactan, pectin, galactan, arabinan, RN-1, HH1-1, LRP1-S2, LRP3-S1.

Characterization and functional study of a chimera galectin from yellow drum Nibea albiflora

Galectins are protein that participates in a variety of immune responses in the process of pathogenic infections. In the present study, a chimera galectin gene was screened from the transcriptome database of Nibea albiflora, which was named as YdGal-3. The results of qRT-PCR showed that the mRNA transcripts of YdGal-3 were ubiquitously distributed in all the detected tissues. After infection with Vibrio harveyi, the expression of YdGal-3 in liver, spleen, and head kidney increased significantly. Immunohistochemistry showed that YdGal-3 protein was widely expressed in the head kidney. The purified YdGal-3 protein by prokaryotic expression agglutinated red blood cells. Sugar inhibition assay showed that the agglutinating activity of YdGal-3 protein was inhibited by different sugars including lactose, D-galactose, and lipopolysaccharide. In addition, we mutated YdGal-3 His 294 into proline (P), alanine (A), glycine (G), and aspartic acid (D), it was further proved that the residue plays a key role in agglutination. YdGal-3 agglutinated some gram-negative bacteria including Pseudomonas plecoglossicida, Vibrio parahemolyticus, V. harveyi, and Aeromonas hydrophila, and exhibited antibacterial activity. These results suggested that YdGal-3 protein played an important role in the innate immunity of N. albiflora.

Crataegus pinnatifida polysaccharide alleviates colitis via modulation of gut microbiota and SCFAs metabolism

Inflammatory bowel disease (IBD) afflicted individual and most medications have side-effects. Crataegus pinnatifida (Hawthorn), which is a safe medicine and food homolog plant, has been reported to prevent colitis in murine. Yet the bioactivity component and the underlying molecular mechanism remain unclear. Here, we established a direct link between colitis induced by dextran sulphate sodium (DSS) in mice and polysaccharide HAW1-2 isolated from hawthorn. Our results showed HAW1-2 restored the pathological lesions in colon and inhibited the expression of inflammatory cytokines including IL-1β, IL-6 and TNF-α. Meanwhile, IKKα/β, IκBα, NF-κB and the phosphorylation levels were inhibited significantly. These findings suggested HAW1-2 could alleviate the inflammation of colon. Further, we found the composition of gut microbiota was modified and Bacteroides including Alistipes and Odoribacter were significantly enriched. Besides, we showed Alistipes and Odoribacter were positively co-related with acetic acid and propionic acid while were negatively co-related with inflammatory cytokines. Finally, we demonstrated the anti-inflammation activity of HAW1-2 might be induced by acetic acid. Together, the present data revealed HAW1-2 could directly modify the gut microbiota, especially for Bacteroides, and generate SCFAs to inhibit colitis. It also implies microbiota-directed intervention in IBD patients should be particularly given more attention.

Galectin-3 is modulated in pancreatic cancer cells under hypoxia and nutrient deprivation

Pancreatic ductal adenocarcinoma is one of the most aggressive tumors with a microenvironment marked by hypoxia and starvation. Galectin-3 has been evaluated in solid tumors and seems to present both pro/anti-tumor effects. So, this study aims to characterize the expression of Galectin-3 from pancreatic tumor cells and analyze its influence for cell survive and motility in mimetic microenvironment. For this, cell cycle and cell death were accessed through flow cytometry. Characterization of inside and outside Galectin-3 was performed through Real-Time Quantitative Reverse Transcription PCR (qRT-PCR), immunofluorescence, Western blot, and ELISA. Consequences of Galectin-3 extracellular inhibition were investigated using cell death and scratch assays. PANC-1 showed increased Galectin-3 mRNA expression when cultivated in hypoxia for 24 and 48 h. After 24 h in simultaneously hypoxic/deprived incubation, PANC-1 shows increased Galectin-3 protein and secreted levels. For Mia PaCa-2, cultivation in deprivation was determinant for the increasing in Galectin-3 mRNA expression. When cultivated in simultaneously hypoxic/deprived condition, Mia PaCa-2 also presented increasing for the Galectin-3 secreted levels. Treatment of PANC-1 cells with lactose increased the death rate when cells were incubated simultaneously hypoxic/deprived condition. Therefore, it is possible to conclude that the microenvironmental conditions modulate the Galectin-3 expression on the transcriptional and translational levels for pancreatic cancer cells.

Galectin-3 and Risk of Late Graft Failure in Kidney Transplant Recipients: A 10-year Prospective Cohort Study

BACKGROUND

Galectin-3 may play a causal role in kidney inflammation and fibrosis, which may also be involved in the development of kidney graft failure. With novel galectin-3-targeted pharmacological therapies increasingly coming available, we aimed to investigate whether galectin-3 is associated with risk of late graft failure in kidney transplant recipients (KTR).

METHODS

We studied adult KTR who participated in TransplantLines Insulin Resistance and Inflammation Biobank and Cohort Study, recruited in a university setting (2001-2003). Follow-up was performed for a median of 9.5 (interquartile range, 6.2-10.2) years. Overall and stratified (Pinteraction < 0.05) multivariable-adjusted Cox proportional-hazards regression analyses were performed to study the association of galectin-3 with risk of graft failure (restart of dialysis or retransplantation).

RESULTS

Among 561 KTR (age 52 ± 12 y; 54% males), baseline median galectin-3 was 21.1 (interquartile range, 17.0-27.2) ng/mL. During follow-up, 72 KTR developed graft failure (13, 18, and 44 events over increasing tertiles of galectin-3). Independent of adjustment for donor, recipient, and transplant characteristics, galectin-3-associated with increased risk of graft failure (hazard ratios [HR] per 1 SD change, 2.12; 95% confidence interval [CI], 1.63-2.75; P < 0.001), particularly among KTR with systolic blood pressure ≥140 mmHg (HR, 2.29; 95% CI, 1.80-2.92; P < 0.001; Pinteraction = 0.01) or smoking history (HR, 2.56; 95% CI, 1.95-3.37; P < 0.001; Pinteraction = 0.03). Similarly, patients in the highest tertile of galectin-3 were consistently at increased risk of graft failure.

CONCLUSIONS

Serum galectin-3 levels are elevated in KTR, and independently associated with increased risk of late graft failure. Whether galectin-3-targeted therapies may represent novel opportunities to decrease the long-standing high burden of late graft failure in stable KTR warrants further studies.

The complexity of tumour angiogenesis based on recently described molecules

Tumour angiogenesis is a crucial factor associated with tumour growth, progression, and metastasis. The whole process is the result of an interaction between a wide range of different molecules, influencing each other. Herein we summarize novel discoveries related to the less known angiogenic molecules such as galectins, pentraxin-3, Ral-interacting protein of 76 kDa (RLIP76), long non-coding RNAs (lncRNAs), B7-H3, and delta-like ligand-4 (DLL-4) and their role in the process of tumour angiogenesis. These molecules influence the most important molecular pathways involved in the formation of blood vessels in cancer, including the vascular endothelial growth factor (VEGF)-vascular endothelial growth factor receptor interaction (VEGFR), HIF1-a activation, or PI3K/Akt/mTOR and JAK-STAT signalling pathways. Increased expression of galectins, RLIP76, and B7H3 has been proven in several malignancies. Pentraxin-3, which appears to inhibit tumour angiogenesis, shows reduced expression in tumour tissues. Anti-angiogenic treatment based mainly on VEGF inhibition has proved to be of limited effectiveness, leading to the development of drug resistance. The newly discovered molecules are of great interest as a potential source of new anti-cancer therapies. Their role as targets for new drugs and as prognostic markers in neoplasms is discussed in this review.

Inhibition of galectin-3 augments the antitumor efficacy of PD-L1 blockade in non-small-cell lung cancer

Multiple clinical trials have shown that monoclonal antibodies (mAbs) against programmed death-ligand 1 (PD-1/PD-L1) can benefit patients with lung cancer by increasing their progression-free survival and overall survival. However, a significant proportion of patients do not respond to anti-PD-1/PD-L1 mAbs. In the present study, we investigated whether galectin (Gal)-3 inhibitors can enhance the antitumor effect of PD-L1 blockade. Using the NSCLC-derived cell line A549, we examined the expression of Gal-3 in lung cancer cells under hypoxic conditions and investigated the regulatory effect of Gal-3 on PD-L1 expression, which is mediated by the STAT3 pathway. We also explored whether Gal-3 inhibition can facilitate the cytotoxic effect of T cells induced by PD-L1 blockade. The effects of combined use of a Gal-3 inhibitor and PD-L1 blockade on tumor growth and T-cell function were also investigated, and we found that hypoxia increased the expression and secretion of Gal-3 by lung cancer cells. Gal-3 increased PD-L1 expression via the upregulation of STAT3 phosphorylation, and administration of a Gal-3 inhibitor enhanced the effect of PD-L1 blockade on the cytotoxic activity of T cells against cancer cells in vitro. In a mouse xenograft model, the combination of a Gal-3 inhibitor and PD-L1 blockade synergistically suppressed tumor growth. Furthermore, the administration of a Gal-3 inhibitor enhanced T-cell infiltration and granzyme B release in tumors. Collectively, our results show that Gal-3 increases PD-L1 expression in lung cancer cells and that the administration of a Gal-3 inhibitor as an adjuvant enhanced the antitumor activity of PD-L1 blockade.

EGFR/FOXO3A/LXR-α Axis Promotes Prostate Cancer Proliferation and Metastasis and Dual-Targeting LXR-α/EGFR Shows Synthetic Lethality

Prostate cancer is the second leading cause of cancer-related death in men. Early prostate cancer has a high 5-year survival rate. However, the five-year survival rate is low in progressive prostate cancer, which manifests as bone metastasis. The EGF receptor overexpression increases during disease progression and in the development of castration-resistant disease, and may be a potential therapeutic target. Liver X receptors (LXRs) are ligand-dependent nuclear receptor transcription factors and consist of two subtypes, LXR-α and LXR-β, which can inhibit tumor growth in various cancer cells. We revealed that LXR-α, but not LXR-β, was reduced in prostate cancer tissues compared with adjacent normal tissues. LXRs' agonist GW3965 enhanced the inhibitory action of LXR-α on the proliferation and metastasis of prostate cancer cells. Furthermore, our results support the notion that LXR-α is regulated by the EGFR/AKT/FOXO3A pathway. As an EGFR inhibitor, Afatinib could weaken AKT activation and increase the expression level of FOXO3A in prostate cancer. In addition, we indicated that the combination of Afatinib and GW3965 simultaneously increased and activated LXR-α, which led to an increase of tumor suppressors, and eventually inhibited tumor progression. Therefore, the combination of EGFR inhibitor and LXRs agonist may become a potential treatment strategy for prostate cancer, especially metastatic prostate cancer.

Macrophages in pancreatic cancer: An immunometabolic perspective

As one of the most fatal gastrointestinal cancers, pancreatic cancer (PC) has a long-term survival rate that has shown limited improvement during recent decades and remains dismal. The poor prognosis is attributed to challenges in early detection, low opportunity for radical resection and resistance to chemotherapy and radiation. Macrophages are one of the most abundant infiltrating immune cells in PC stroma, and they can crosstalk with cancer cells, adipocytes and other stromal cells to modulate metabolism, inflammation and immune status, create an immunosuppressive tumor microenvironment (TME), and ultimately facilitate tumor initiation and progression. In this review, we summarize recent advances in our understanding of macrophage origin, distribution and polarization, as well as provide a thorough review of the role macrophages in PC carcinogenesis and development, as well as the underlying molecular mechanism. Additionally, we investigated macrophage targets in preclinical and clinical trials to evaluate their potential therapeutic value in PC.

Quinoline-Pyrazole Scaffold as a Novel Ligand of Galectin-3 and Suppressor of TREM2 Signaling

Galectin-3 has been identified as a critical player in driving the neuroinflammatory responses in Alzheimer's disease (AD). A key feature of this function of galectin-3 is associated with its interaction with the triggering receptor expressed on myeloid cells-2 (TREM2). Herein, we report a high-throughput screening (HTS) platform that can be used for the identification of inhibitors of TREM2 and galectin-3 interaction. We have utilized this HTS assay to screen a focused library of compounds optimized for the central nervous system (CNS)-related diseases. MG-257 was identified from this screen as the first example of a small molecule that can attenuate TREM2 signaling based on its high affinity to galectin-3 (endogenous ligand of TREM2). Remarkably, MG-257 reduced the levels of proinflammatory cytokines in activated microglial cells, which highlights its ability to inhibit the neuroinflammatory response associated with AD.

Construction of a Stapled α-Helix Peptide Library Displayed on Phage for the Screening of Galectin-3-Binding Peptide Ligands

A stapled α-helix peptide library was designed and constructed using a chemically modified phage display system for screening stapled-peptide ligands against target proteins. The α-helix peptide library, with two cysteine residues on the opposite side of the randomized face, was modified with a rigid hydrocarbon staple linker on a phage. The stapled α-helix peptide phage library was screened against galectin-3 (Gal-3), a cancer-related galactose-binding protein. The obtained stapled peptides showed a high binding affinity (K _d = 0.45 μM) despite being nonsugar ligands. The stapled modification played important roles in stabilizing the α-helical structure that contributed to the high binding affinity to Gal-3. In addition, the best stapled peptide ligands showed specific binding to Gal-3 among various carbohydrate-binding proteins. Thus, the designed α-helix peptide phage library with a constrained structure by the staple linker will advance the discovery of peptide ligands with improved specificity and affinity.

The Galectin Family as Molecular Targets: Hopes for Defeating Pancreatic Cancer

Galectins are a family of proteins that bind β-galactose residues through a highly conserved carbohydrate recognition domain. They regulate several important biological functions, including cell proliferation, adhesion, migration, and invasion, and play critical roles during embryonic development and cell differentiation. In adults, different galectin members are expressed depending on the tissue type and can be altered during pathological processes. Numerous reports have shown the involvement of galectins in diseases, mostly inflammation and cancer. Here, we review the state-of-the-art of the role that different galectin family members play in pancreatic cancer. This tumor is predicted to become the second leading cause of cancer-related deaths in the next decade as there is still no effective treatment nor accurate diagnosis for it. We also discuss the possible translation of recent results about galectin expression and functions in pancreatic cancer into clinical interventions (i.e., diagnosis, prediction of prognosis and/or therapy) for this fatal disease.

Corn silk crude polysaccharide exerts anti-pancreatic cancer activity by blocking the EGFR/PI3K/AKT/CREB signaling pathway

S1, a crude polysaccharide from corn silk, may significantly inhibit pancreatic cancer cell proliferation in vitro and in vivo. It can induce apoptosis, arrest the cell cycle in S phase and impede pancreatic cancer cell migration and invasion.

Prognostic and diagnostic significance of galectins in pancreatic cancer: a systematic review and meta-analysis

Background

Galectins constitute a family of β-galactoside-binding proteins, which influence various hallmarks of pancreatic cancer, including cell proliferation, invasion and migration; immune escape; and angiogenesis. Although many studies have concentrated on the role of galectins in pancreatic cancer, the results remain controversial. Hence, we performed a comprehensive meta-analysis to clarify the precise diagnostic and prognostic value of galectins in pancreatic cancer.

Methods

PubMed/MEDLINE, EMBASE and Web of Science were used to search related published literature up to July 2019. Pooled hazard ratios (HRs), diagnostic accuracy variables and related 95% confidence intervals (CIs) were calculated using STATA 14.0 software.

Results

Eleven studies including 1227 participants met our inclusion criteria. High expression of galectin family was not correlated with overall survival (OS) in pancreatic cancer (HR, 1.19; 95% CI 0.67-2.11). According to subgroup analysis, high levels of galectin-1 were significantly correlated with worse OS in pancreatic cancer (HR, 4.77; 95% CI 2.47-9.21), while high levels of tandem-repeat galectins (galectin-4 or galectin-9) predicted both better OS (HR, 0.63; 95% CI 0.46-0.86) and disease-free survival (DFS) (HR, 0.63; 95% CI 0.48-0.83). The expression levels of galectin-3 did not directly correlate with prognosis (HR, 0.99; 95% CI 0.40-2.46). The pooled sensitivity, specificity, positive likelihood ratio, and negative likelihood ratios of galectin-3 were 0.64 (95% CI 0.41-0.82), 0.76 (95% CI 0.59-0.88), 2.70 (95% CI 1.21-6.1), and 0.47 (95% CI 0.23-0.98), respectively. The area under the curve (AUC) of galectin-3 was 0.77.

Conclusion

Taken together, our results suggest that high expression of galectin-1 and low levels of galectin-4 or galectin-9 are predictors of worse prognosis in pancreatic cancer patients. The expression of galectin-3 was not directly related to OS and other clinical characteristics. Although galectin-3 exhibited some diagnostic value in patients with pancreatic cancer in this meta-analysis, clinical application prospects remain to be validated. Further studies are warranted to confirm and strengthen these findings.

Evolving trends in pancreatic cancer therapeutic development

Despite advances in translational research, the overall 5-year survival for pancreatic cancer remains dismal and with rising incidence pancreatic cancer is predicted to be the second leading cause of cancer death for many developed countries. Surgical intervention followed by cytotoxic chemotherapy are currently the best options for treatment, but disease recurrence is very common. Efforts to develop new therapeutic agents and delivery systems are necessary to achieve better clinical efficacy with less toxicity. Promising prospects are arising with new preclinical and clinical therapeutic strategies using small molecule targeted therapies, RNAi, stromal therapies, and immunotherapies. With a better understanding of the biology to aid target selection and discovery of biomarkers to aid precision medicine, better opportunities will evolve to shape the therapeutic landscape, enhance patient quality of life and increase overall survival.