Galectin-3 Research Articles

Prognostic biomarkers in and selection of surgical patients with hepatocellular carcinoma.

Prognostic biomarkers in and selection of surgical patients with hepatocellular carcinoma.

Immunohistochemical study of CD147 and matrix metalloproteases in meningiomas

Background/Aim: Expression of extracellular matrix proteins and metalloproteases (MMPs) has been implicated in neoplasm recurrence. Some recent studies have suggested a correlation between matrix modifier proteins and recurrence or invasion of meningiomas. Based on previous data, the aim of this study was to find a correlation between the immunohistochemical (IHC) expression patterns of a group of matrix modifier proteins, including CD147, Matrix Metalloprotease 2 and 9 (MMP2 and 9, respectively), Epithelial Cadherin (ECAD), and Galectin-3 (GAL3) with World Health Organization (WHO)-defined grade, brain invasion, recurrence, and other clinicopathological features. Methods: This study was a cohort study. All patients with meningioma who underwent resection over a 10-year period were identified from the electronic pathology archives. Tissue microarrays (TMAs) were created for IHC studies, and IHC staining was performed using standard methodology. Results: A total of 231 cases fulfilled the study criteria. Histological review identified 198 grade 1 tumors (85.3%), 28 grade 2 tumors (12.6%), and five grade 3 tumors (2.2%). CD147 was determined to be positively correlated with WHO-defined grade (P=0.009). ECAD, MMP2, MMP9, GAL3 were not found to be correlated with brain invasion, recurrence, or WHO grade. Conclusion: The study results demonstrated that CD147 could be a target for diagnosis, prognosis, and treatment of meningiomas.

Candida albicans Promotes Oral Cancer via IL-17A/IL-17RA-Macrophage Axis.

The association between Candida albicans (C. albicans) and oral cancer (OC) has been noticed for a long time, but the mechanisms for C. albicans promoting OC are rarely explored. In this study, we determined that C. albicans infection promoted OC incidence in a 4-nitroquinoline 1-oxide (4NQO)-induced mouse tongue carcinogenesis model as well as promoted OC progression in a tongue tumor-bearing mouse model (C3H/HeN-SCC VII). We then demonstrated that tumor-associated macrophage (TAMs) infiltration was elevated during C. albicans infection. Meanwhile, the attracted TAMs polarized into M2-like macrophages with high expression of programmed death ligand 1 (PD-L1) and galectin-9 (GAL-9). Further analysis suggested that the interleukin (IL)-17A/IL-17RA pathway activated in OC cells was a contributor to the excessive TAMs infiltration in C. albicans-infected mice. Thus, we constructed IL-17A neutralization and macrophage depletion experiments in C3H/HeN-SCC VII mice to explore the role of IL-17A/IL-17RA and TAMs in OC development caused by C. albicans infection. The results showed that both IL-17A neutralization and macrophage depletion tended to reduce the TAMs number and tumor size in mice with C. albicans infection. Collectively, our finding revealed that C. albicans promoted OC development via the IL-17A/IL-17RA-macrophage axis, opening perspectives for revealing C. albicans-tumor immune microenvironment links. IMPORTANCE The relationship between fungi and cancer is gradually receiving attention. Among them, some clinical evidence has shown that Candida may be a contributor to gastrointestinal cancers, especially oral cancer. However, the underlying mechanisms for Candida promoting oral cancer need to be explored. For this reason, this study demonstrated the role of C. albicans in oral cancer development. Moreover, this study revealed the underlying mechanisms for C. albicans promoting oral cancer from the perspective of the tumor immune microenvironment.

Estrogen receptors regulate galectin‑3 in androgen‑independent DU‑145 prostate cancer cells.

The aim of the present study was to investigate the role of estrogen receptor (ER)α and ERβ, and galectin‑3 (GAL‑3) in migration and invasion of androgen‑independent DU‑145 prostate cancer cells, and to examine the regulation of the expression of GAL‑3 by the activation of these receptors. Wound healing and cell invasion assays were performed using the control (basal level of cellular function) and treated DU‑145 cells. At 24h of treatment, 17β‑estradiol (E2), the ERα‑selective agonist, 4,4',4"‑(4‑propyl‑(1H)‑pyrazole‑1,3,5‑triyl)trisphenol (PPT), or the ERβ‑selective agonist, 2,3‑bis(4‑hydroxyphenyl)‑propionitrile (diarylprepionitrile; DPN), increased the migration and invasion of the DU‑145 cells. Pre‑treatment with the ERα‑ and ERβ‑selective antagonists blocked these effects, indicating that ERα and ERβ are upstream receptors regulating these processes. Western blot analysis and immunofluorescence staining for the detection of the GAL‑3 were performed using the control and treated DU‑145 cells. Treatment of the DU‑145 cells with E2, PPT or DPN for 24h increased the expression of the GAL‑3 compared to the control. Furthermore, a specific inhibitor of GAL‑3 (VA03) inhibited the migration and invasion of DU‑145 cells, indicating the involvement of the complex ERα/GAL‑3 and ERβ/GAL‑3 in the regulation of these processes. On the whole, the present study demonstrates that the activation of both ERs increases the expression and signaling of GAL‑3, and promotes the migration and invasion of DU‑145 cells. The findings of the present study provide novel insight into the signatures and molecular mechanisms of ERα and ERβ in DU‑145 cells.

Niche-expressed Galectin-1 is involved in pre-B acute lymphoblastic leukemia relapse through pre-B cell receptor activation

B-cell acute lymphoblastic leukemia (B-ALL) reflects the malignant counterpart of developing B cells in the bone marrow (BM). Despite tremendous progress in B-ALL treatment, the overall survival of adults at diagnosis and patients at all ages after relapse remains poor. Galectin-1 (GAL1) expressed by BM supportive niches delivers proliferation signals to normal pre-B cells through interaction with the pre-B cell receptor (pre-BCR). Here, we asked whether GAL1 gives non-cell autonomous signals to pre-BCR+ pre-B ALL, in addition to cell-autonomous signals linked to genetic alterations. In syngeneic and patient-derived xenograft (PDX) murine models, murine and human pre-B ALL development is influenced by GAL1 produced by BM niches through pre-BCR-dependent signals, similarly to normal pre-B cells. Furthermore, targeting pre-BCR signaling together with cell-autonomous oncogenic pathways in pre-B ALL PDX improved treatment response. Our results show that non-cell autonomous signals transmitted by BM niches represent promising targets to improve B-ALL patient survival.

Mechanistic Insights into the Role of OPN in Mediating Brain Damage via Triggering Lysosomal Damage in Microglia/Macrophage.

We previously found that osteopontin (OPN) played a role in hypoxia-ischemia (HI) brain damage. However, its underlying mechanism is still unknown. Bioinformatics analysis revealed that the OPN protein was linked to the lysosomal cathepsin B (CTSB) and galectin-3 (GAL-3) proteins after HI exposure. In the present study, we tested the hypothesis that OPN was able to play a critical role in the lysosomal damage of microglia/macrophages following HI insult in neonatal mice. The results showed that OPN expression was enhanced, especially in microglia/macrophages, and colocalized with lysosomal-associated membrane protein 1 (LAMP1) and GAL-3; this was accompanied by increased LAMP1 and GAL-3 expression, CTSB leakage, as well as impairment of autophagic flux in the early stage of the HI process. In addition, the knockdown of OPN expression markedly restored lysosomal function with significant improvements in the autophagic flux after HI insult. Interestingly, cleavage of OPN was observed in the ipsilateral cortex following HI. The wild-type OPN and C-terminal OPN (Leu152-Asn294), rather than N-terminal OPN (Met1-Gly151), interacted with GAL-3 to induce lysosomal damage. Furthermore, the secreted OPN stimulated lysosomal damage by binding to CD44 in microglia in vitro. Collectively, this study demonstrated that upregulated OPN in microglia/macrophages and its cleavage product was able to interact with GAL-3, and secreted OPN combined with CD44, leading to lysosomal damage and exacerbating autophagosome accumulation after HI exposure.

Abstract P5-02-51: Single-cell transcriptome reveals distinct peripheral blood immune landscapes associated with sensitivity to anti-HER2 treatment in HER2-positive metastatic breast cancer patients

Abstract Background: Different immune cell states reflect distinct tumor microenvironment and led to various clinical outcomes for cancer patients. However, very few studies examined the contribution of peripheral blood (PB) immune landscapes to the treatment response due to the limited applications. This study aimed to explore the circulating immune cell landscapes associated the sensitivity to cytotoxic chemotherapy with trastuzumab in HER2 positive metastatic breast cancer patients. Methods: Whole blood were drawn at baseline and after 2 cycles of trastuzumab plus cytotoxic chemotherapy from six patients (3 responders and 3 non-responders). Approximately 3,500 to 10,000 peripheral blood mononuclear cells per patients were profiled using single-cell RNA sequencing (scRNA-seq). scRNA-seq data were further processed and analyzed using Seurat package version 3.1. Cell populations were clustered using the Louvain algorithm and subsequently annotated using known marker genes. Differential abundance in cell population was quantified using MiloR and differentially expressed genes were detected using MAST between responders and non-responders. Results: After removing low quality cells, a total of 65,295 cells were clustered into 18 clusters. CD8 Effector T, CD4 Naïve T, CD4 Effector T, Cytotoxic NK, Naïve B, Plasma B and Monocytes were significantly enriched in responders compared to non-responders. Especially, CD8 Effector T, NK, Plasma B and Classical Monocytes showed distinct patterns that those cells were enriched in pre-treatment than post-treatment of responder but not in non-responder. From the differentially expressed gene analysis, cytotoxic or costimulatory marker genes (GZMK, GZMA, GNLY, CCL5, NKG7, PRF1) were enriched in responders. While, exhausted or coinhibitory marker genes (DNAJB1, LGALS9, HAVCR2) were enriched in non-responders. Gene set enrichment analysis revealed four pathways associated with T cell, B cell receptor signaling, NK cell mediated cytotoxicity and Cytokine-cytokine receptor interaction which showed differences between responders and non-responders following chemotherapy. Finally, validation with flow cytometry using independent cohort showed that constant expression manner in HAVCR2, LGALS9 and LGALS3 genes. Conclusions: Single-cell transcriptome analysis identified distinct PB immune landscapes associated with treatment response in HER2-positive metastatic breast cancer patients. Differential abundance and unique gene expression programs of immune cell populations could serve as potential predictive biomarkers for anti-HER2 therapy. Citation Format: Jongwon Lee, Jungmin Choi, In Hae Park. Single-cell transcriptome reveals distinct peripheral blood immune landscapes associated with sensitivity to anti-HER2 treatment in HER2-positive metastatic breast cancer patients [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P5-02-51.

Targeting galectin-driven regulatory circuits in cancer and fibrosis.

Galectins are a family of endogenous glycan-binding proteins that have crucial roles in a broad range of physiological and pathological processes. As a group, these proteins use both extracellular and intracellular mechanisms as well as glycan-dependent and independent pathways to reprogramme the fate and function of numerous cell types. Given their multifunctional roles in both tissue fibrosis and cancer, galectins have been identified as potential therapeutic targets for these disorders. Here, we focus on the therapeutic relevance of galectins, particularly galectin 1 (GAL1), GAL3 and GAL9 to tumour progression and fibrotic diseases. We consider an array of galectin-targeted strategies, including small-molecule carbohydrate inhibitors, natural polysaccharides and their derivatives, peptides, peptidomimetics and biological agents (notably, neutralizing monoclonal antibodies and truncated galectins) and discuss their mechanisms of action, selectivity and therapeutic potential in preclinical models of fibrosis and cancer. We also review the results of clinical trials that aim to evaluate the efficacy of galectin inhibitors in patients with idiopathic pulmonary fibrosis, nonalcoholic steatohepatitis and cancer. The rapid pace of glycobiology research, combined with the acute need for drugs to alleviate fibrotic inflammation and overcome resistance to anticancer therapies, will accelerate the translation of anti-galectin therapeutics into clinical practice.

Spatial regulation of the glycocalyx component podocalyxin is a switch for prometastatic function.

The glycocalyx component and sialomucin podocalyxin (PODXL) is required for normal tissue development by promoting apical membranes to form between cells, triggering lumen formation. Elevated PODXL expression is also associated with metastasis and poor clinical outcome in multiple tumor types. How PODXL presents this duality in effect remains unknown. We identify an unexpected function of PODXL as a decoy receptor for galectin-3 (GAL3), whereby the PODXL-GAL3 interaction releases GAL3 repression of integrin-based invasion. Differential cortical targeting of PODXL, regulated by ubiquitination, is the molecular mechanism controlling alternate fates. Both PODXL high and low surface levels occur in parallel subpopulations within cancer cells. Orthotopic intraprostatic xenograft of PODXL-manipulated cells or those with different surface levels of PODXL define that this axis controls metastasis in vivo. Clinically, interplay between PODXL-GAL3 stratifies prostate cancer patients with poor outcome. Our studies define the molecular mechanisms and context in which PODXL promotes invasion and metastasis.

Protective Effects of Fuziline on Dobutamine-Induced Heart Damage in Mice.

Fuziline is one of the many antioxidants currently being tested to treat cardiac damage. In our study, histopathological and biochemical effects of fuziline were investigated in mice with dobutamine-induced heart damage in vitro. Thirty-two adult male BALB/c mice, average weight of 18-20 g, were randomly divided into four groups - Group 1 (sham, n=8), Group 2 (control, dobutamine, n=8), Group 3 (treatment 1, dobutamine + fuziline, n=8), and Group 4 (treatment 2, fuziline, n=8). Biochemical parameters and total antioxidant status (TAS), total oxidant status (TOS), and oxidative stress index (OSI) values were measured. Interleukin 1 beta (IL-1β), NLR family, pyrin domain containing protein 3 (NLRP3), 8-hydroxy-deoxyguanosine (8-OHDG), gasdermin D (GSDMD), and galectin 3 (GAL-3) levels were analyzed by enzyme-linked immunosorbent assay method, and histopathological examination of heart tissues was performed. When dobutamine + fuziline and fuziline groups were compared, troponin-I (P<0.05), NLRP3 (P<0.001), GSDMD (P<0.001), 8-OHDG (P<0.001), IL-1β (P<0.001), and GAL-3 (P<0.05) were found to be statistically significant. TOS level was the highest in the dobutamine group (P<0.001) and TAS level was the highest in the fuziline group (P<0.001). OSI level was statistically significant between the groups (P<0.001). In histopathological examination, focal necrosis areas were smaller in the dobutamine + fuziline group than in the dobutamine group, and cardiac myocytes were better preserved. Fuziline markedly reduced cardiac damage and pyroptosis in mice with dobutamine-induced heart damage by lowering the levels of GSDMD, 8-OHDG, IL-1β, and GAL-3. It also prevented necrosis of cardiac myocytes in histopathological evaluation.

Nipple fluid for breast cancer diagnosis using the nanopore of Phi29 DNA-packaging motor

Detection of cancer in its early stage is a challenging task for oncologists. Inflammatory breast cancer has symptoms that are similar to mastitis and can be mistaken for microbial infection. Currently, the differential diagnosis between mastitis and Inflammatory breast cancer via nipple aspirate fluid (NAF) is difficult. Here, we report a label-free and amplification-free detection platform using an engineered nanopore of the phi29 DNA-packaging motor with biomarker Galectin3 (GAL3), Thomsen-Friedenreich (TF) binding peptide as the probe fused at its C-terminus. The binding of the biomarker in NAF samples from breast cancer patients to the probe results in the connector's conformational change with a current blockage of 32 %. Utilization of dwell time, blockage ratio, and peak signature enable us to detect basal levels of biomarkers from patient NAF samples at the single-molecule level. This platform will allow for breast cancers to be resolved at an early stage with accuracy and thoroughness.

Plasma levels of galectin-3 in residents of the Podillya region of Ukraine without signs of cardiovascular pathology carriers of different variants of the coding gene (LGALS-3, rs 2274273)

Annotation. The purpose of the study is to investigate the plasma level of galectin-3 in postmenopausal women without signs of cardiovascular pathology and its possible association with the structural and functional parameters of the myocardium in carriers of different polymorphic variants of the coding gene (LGALS-3, rs2274273). 67 women of postmenopausal age (average age 56.43±0.64 years) without signs of cardiovascular pathology residents of the Podillya region of Ukraine were examined. In addition to the general clinical examination, the research used the enzyme immunoassay method to determine the level of galectin-3 in blood plasma, genotyping of the LGALS3 gene at the rs2274273 locus by means of polymerase chain reaction, and ultrasound of the heart. Statistical processing of the obtained results was carried out using the package of statistical programs SPSS, STATISTICA v. 10.0. By means of correlation analysis with the calculation of Spearman's rank correlation coefficients (r), an assessment of the possible association of the plasma level of the biomarker and the structural and functional indicators of the heart was carried out. The critical value of the significance level (p) was ≤0.05. In the examined population of women, there was no significant difference between the frequency of occurrence of the GA and GG genotypes carriers of the galectin-3 gene locus rs2274273: 49.25% (n=33) and 40.30% (n=27), respectively (p&gt;0.05). The AA genotype variant was found in 10.45% (n=7) of individuals, which is significantly less frequent than both the GA and GG genotypes (p&lt;0.01). The frequency of distribution of genotypes corresponded to the Hardy-Weinberg equilibrium. The average level of galletin-3 in blood plasma in women was 6.68±0.30 ng/ml, it was within the generally accepted norms and did not reliably differ from the corresponding indicators in men of the same region. No significant difference in plasma concentrations of galectin-3 was found in carriers of different polymorphic variants of the galectin-3 gene. Correlation between the level of galectin-3 in the blood plasma and most indicators of intracardiac and systemic hemodynamics in women without cardiovascular pathology was not found. In the future, it is planned to study the formation of prerequisites for chronic heart failure (CHF) in women with EH based on indicators of the plasma level of galectin-3 in carriers of polymorphic variants of the coding gene (LGALS-3, rs2274273).

DC-SIGN and Galectin-3 individually and collaboratively regulate H5N1 and H7N9 avian influenza A virus infection via interaction with viral envelope hemagglutinin protein.

DC-SIGN and Galectin-3 are two different lectins and have been reported to participate in regulation of several virus infections. WHO has pointed that H5N1 and H7N9 avian influenza viruses (AIVs) play continuous threats to global health. AIV hemagglutinin (HA) protein-a highly glycosylated protein-mediates influenza infection and was proposed to have DC-SIGN and Gal3 interactive domains. This study aims to address the individual and collaborative roles of DC-SIGN and Gal3 toward AIVs infection. Firstly, A549 cells with DC-SIGN expression or Gal3-knockdown, via lentiviral vector-mediated CD209 gene expression or LGALS-3 gene knockdown, respectively were generated. Quantitative reverse transcription PCR (qRT-PCR) results indicated that DC-SIGN expression and Gal3 knockdown in A549 cells significantly promoted and ameliorated HA or NP gene expression, respectively after H5N1 and H7N9-reverse genetics (RG) virus postinfections (P<0.05). Similar results observed in immunoblotting, indicating that DC-SIGN expression significantly facilitated H5N1-RG and H7N9-RG infections (P<0.05), whereas Gal3 knockdown significantly reduced both viral infections (P<0.05). Furthermore, we found that DC-SIGN and Gal3 co-expression significantly enhanced infectivity of both H5N1-RG and H7N9-RG viruses (P<0.01) and higher regulatory capabilities by DC-SIGN and Gal3 in H5N1-RG than H7N9-RG were noted. The promoting effect mainly relied on exogenous Gal3 and DC-SIGN directly interacting with the HA protein of H5N1 or H7N9 AIVs, subsequently enhancing virus infection. This study sheds light on two different lectins individually and collaboratively regulating H5N1 and H7N9 AIVs infection and suggests that inhibitors against DC-SIGN and Gal3 interacting with HA could be utilized as alternative antiviral strategies.

Increased Expression of Galectin-3 in Skin Fibrosis: Evidence from In Vitro and In Vivo Studies.

Skin fibrosis is a hallmark of a wide array of dermatological diseases which can greatly impact the patients' quality of life. Galectin-3 (GAL-3) has emerged as a central regulator of tissue fibrosis, playing an important pro-fibrotic role in numerous organs. Various studies are highlighting its importance as a skin fibrotic diseases biomarker; however, there is a need for further studies that clarify its role. This paper aims to ascertain whether the expression of GAL-3 is increased in relevant in vitro and in vivo models of skin fibrosis. We studied the role of GAL-3 in vitro using normal human dermal fibroblasts (NHDF) and fibrocytes. In addition, we used a skin fibrosis murine model (BALB/c mice) and human biopsies of healthy or keloid tissue. GAL-3 expression was analyzed using real time PCR, Western blot and immunostaining techniques. We report a significantly increased expression of GAL-3 in NHDF and fibrocytes cell cultures following stimulation with transforming growth factor β1 (TGFβ1). In vivo, GAL-3 expression was increased in a murine model of systemic sclerosis and in human keloid biopsies. In sum, this study underlines the involvement of GAL-3 in skin fibrosis using several models of the disease and highlights its role as a relevant target.

Evulation of prolidase enzyme, and galectin levels as a marker for fibrosis in patients with chronic hepatitis B.

The fibrosis can be detected using non-invasive methods including prolidase activity, proline levels and galectin-3 (GAL-3) detection in the serum. The aim of this study was to investigate the liver fibrosis through non-invasive methods in chronic hepatitis B patients. This prospective case control study includes 56 patients with Chronic Active Hepatitis B (CAHB), 57 patients with Inactive Hepatitis B (IHB), and 60 healthy matched control subjects. The first group included the CAHB [hepatitis B surface antigen (HBsAg): positive; HBV DNA >2,000 IU/mL; normal or high alanine aminotransferase (ALT) value] undergo a liver biopsy, while the second group included the IHB (HBsAg: positive; HBV DNA: negative; normal ALT value). The third group comprised the healthy controls. Serum prolidase enzyme activities (SPEA), proline and galectin-3 levels were measured for each group. Patients with CAHB had significantly higher SPEA levels (1,004.3±186.8 IU/L) than did the controls (196.5±306 IU/L) (p<0.001). Significantly higher serum GAL-3 levels were found in the CHB group compared with HBV carrier and the control groups (27.4±32.2 ng/mL, 6.5±13.4 ng/mL, 3.1±5.7 ng/mL, respectively, p<0.001). The relationship between serum prolidase activity, hidroxiprolyne and fibrosis (p<0.05). There were no significant differences in ALT levels between inactive HBV carriers and the control groups (p>0.05). We suppose that hidroxiprolyne levels and prolidase enzyme activity might be an indicator as a marker for fibrosis in CAHB and the evaluation of response to treatment.

Lyt-200, a Humanized Anti-Galectin-9 Antibody, Exhibits Preclinical Efficacy in Models of Hematological Malignancies

Patients with relapse and refractory (R/R) hematological malignancies typically have 5-year overall survival rates of less than 50% when receiving chimeric antigen receptor (CAR) T-cell therapy and less than 30% after receiving hematopoietic stem cell transplantation (HSCT). Human leukemia cells utilize a variety of biochemical mechanisms, which allow them to escape host immune surveillance. These molecular pathways cause impairment of the anti-cancer activities of immune cells, which could attack and kill leukemia cells. These dismal outcomes for patients with R/R disease highlight the need for novel treatment regimens when current therapeutic options are exhausted. Galectins are s-type lectins that promote diverse biological processes including adhesion, signaling, and immunosuppression. In acute myeloid leukemia (AML), galectin-9 (GAL-9) maintains the leukemia initiating cell (LIC) population and plays an important role in treatment resistance. We recently tested LYT-200, a fully humanized IgG4 αGAL-9 monoclonal antibody, developed by PureTech Health, which has so far been well tolerated with no dose limiting toxicities in a Phase I clinical trial for solid tumors (NCT04666688). We tested LYT-200 in vitro and in vivo across multiple hematological malignancies. Flow cytometry was used to assess the surface expression of GAL-9 on human B-ALL, AML, T-cell acute lymphoblastic leukemia (T-ALL), and diffuse large B-cell lymphoma (DLBCL) cell lines relative to receptor T-cell immunoglobulin and mucin domain-containing protein-3 (TIM-3) and Programmed cell death protein-1 (PD-1) expression. Compared to healthy human peripheral blood mononuclear cells (PBMCs), where GAL-9 surface expression was low or absent depending on the immune cell, GAL-9 was highly expressed on the surface of all human blood cancer cell lines tested (>100-fold increase). Notably, GAL-9 expression was comparable to PD-1 surface expression and higher than that of TIM-3 on AML, B-ALL, T-ALL, and DLBCL cells. Treating all cell lines with LYT-200 relative to control immunoglobulin resulted in extensive cell death, which occurred after 48 and 72 hours of treatment. Furthermore, a side-by-side comparison with αTIM-3 antibody treatment at equivalent concentrations, revealed that LYT-200 treatment was significantly more effective at killing blood cancer cells at low doses of 10-100 ng/mL in vitro. The in vitro efficacy of LYT-200 against multiple blood cancer subtypes extended to in vivo protection and survival benefit in murine models of T-ALL and AML, both in immunocompromised and immunocompetent mice. When immunocompromised mice were transplanted with human T-ALL cell lines or patient-derived samples, single-agent treatment with LYT-200 (1.5 mg/kg/weekly) was comparable to survival results obtained with methotrexate (0.75 mg/kg/weekly) administration. Notably, the combination of LYT-200 and methotrexate treatments led to the best survival outcomes in both contexts. Similar results were obtained in xenograft studies of AML, where single-agent LYT-200 (1.5 mg/kg/weekly) treatment was more effective at protecting mice than cytarabine (100 mg/kg/weekly). However, combining both treatments resulted in the best survival outcomes with greater than 80% of mice surviving over 2 months after disease appearance. In all, our results demonstrate that GAL-9 is an important driver of multiple blood cancer subtypes and that targeting GAL-9 with LYT-200 represents a potential novel treatment strategy which warrants additional pre-clinical and clinical testing.

TMIC-49. CHITINASE-3-LIKE 1 PROTEIN COMPLEXES REGULATE PD-1 SIGNALING-MEDIATED IMMUNOSUPPRESSION IN GLIOBLASTOMA

Abstract Glioblastoma (GBM), the most common and lethal brain tumor with a median survival rate of only 15 months, remains largely incurable despite intensive multimodal treatment, including immunotherapeutic strategies being tested in clinical trials. GBM is highly immunosuppressive and resistant to immunotherapy because glioma cells escape from effective antitumor immunity through programing the tumor microenvironment (TME). Owing to the tremendous heterogeneity and plasticity of tumor cells and the surrounding TME, understanding the mechanisms of immune evasion by GBM remains elusive. We have recently discovered that the Chitinase-3-like-1 (CHI3L1)-Galectin-3 (Gal3) protein binding complex can selectively promote tumor-associated macrophage migration and infiltration with a protumor M2-like phenotype and T cell-mediated immunosuppression, which are governed by a transcriptional program of NF-κB/CEBPβ in the CHI3L1/Gal3-PI3K/AKT/mTOR axis. The immunoprecipitation coupled to liquid chromatography-mass spectrometry analysis revealed that galectin 3–binding protein (Gal3BP) competes with Gal3 to bind with CHI3L1 for negative regulation of the CHI3L1-Gal3 mediated processes. Interestingly, a newly-developed Gal3BP mimetic peptide can disrupt CHI3L1-Gal3 interaction, resulting in decreasing migration of M2-like bone marrow-derived macrophages (BMDMs), increasing CD8+ T cell infiltration, reversing immunosuppression, and inhibiting tumor progression in vitro and in vivo. Analyzing PD-1 signaling activation, we found that the Gal3BP mimetic peptide significantly decreased PD-L1 expression in tumor cells. Correlation analysis showed that CHI31L and Gal3 (encoded by LGALS3 gene) are significantly associated with both PD-L1 and PD-L2 in GBM patient samples. Furthermore, overexpression of CHI3L1 increased expression levels of PD-L1 and PD-L2, and CHI3L1 deletion decreased their expression in GBM patient-derived neurosphere lines. The treatment with recombinant CHI3L1 protein significantly increased PD-L1 and PD-L2 expression in M2-like BMDMs (with high levels of endogenous Gal3). Collectively, these data suggest that CHI3L1 protein complexes control the GBM immunosuppressive microenvironment by PD-1/PD-L1/PD-L2 signaling, providing new immunotherapeutic strategies for this brain cancer.

The Correlation of Ten Immune Checkpoint Gene Expressions and Their Association with Gastric Cancer Development.

In the immunotherapy based on immune checkpoint inhibition (IC), additional ICs are being studied to increase its effectiveness. An almost unstudied feature is the possible co-expression of ICs, which can determine the therapeutic efficacy of their inhibition. For the selection of promising ICs, information on the association of their expression with cancer development may be essential. We have obtained data on the expression correlation of ADAM17, PVR, TDO2, CD274, CD276, CEACAM1, IDO1, LGALS3, LGALS9, and HHLA2 genes in gastric cancer (GC). All but one, TDO2, have other IC genes with co-expression at some stage. At the metastatic stage, the expression of the IDO1 does not correlate with any other gene. The correlations are positive, but the expressions of the CD276 and CEACAM1 genes are negatively correlated. The expression of TDO2 and LGALS3 is associated with GC metastasis. The expression of TDO2 four-fold higher in metastatic tumors than in non-metastatic tumors, but LGALS3 was two-fold lower. The differentiation is associated with IDO1. The revealed features of TDO2, with a significant increase in expression at the metastatic stage and the absence of other IC genes with correlated expression indicates that the prospect of inhibiting TDO2 in metastatic GC. IDO1 may be considered for inhibition in low-differentiated tumors.

The impact of myocardial fibrosis biomarkers in a heart failure population with atrial fibrillation—The HARVEST-Malmö study

Several studies suggest that circulating biomarkers of myocardial fibrosis are associated with worse prognosis in subjects with atrial fibrillation (AF). Here, we aimed to explore associations between fibrosis biomarkers, prevalent AF, and left atrial volume (LAV) enlargement in subjects with heart failure (HF). Additionally, we evaluated the prognostic impact of fibrotic biomarkers in HF with co-existing AF. Patients hospitalized for HF (n = 316, mean age 75 years; 30% women) were screened for AF. Seven proteins previously associated with myocardial fibrosis [metalloproteinase inhibitor 4 (TIMP-4), suppression of tumorigenicity 2 (ST-2), galectin-3 (GAL-3), growth/differentiation factor-15 (GDF-15), and matrix metalloproteinase 2, 3, and 9 (MMP-3, MMP-3, and MMP-9, respectively)] were analyzed using a proximity extension assay. Proteins with significant Bonferroni-corrected associations with mortality and re-hospitalization risk were taken forward to multivariable Cox regression analyses. Further, Bonferroni-corrected multivariable logistic regression models were used to study associations between protein plasma levels, prevalent AF, and severely enlarged left atrial volume index (LAVI ≥ 48 ml/m2). Prevalent AF was observed in 194 patients at the hospitalization of whom 178 (92%) were re-hospitalized and 111 (57%) died during the follow-up period. In multivariable logistic regression models, increased plasma levels of TIMP-4, GDF-15, and ST-2 were associated with the prevalence of AF, whereas none of the seven proteins showed any significant association with severely enlarged LAVI. Increased plasma levels of five proteins yielded significant associations with all-cause mortality in patients with co-existing AF; TIMP-4 (HR 1.33; CI95% 1.07-1.66; p = 0.010), GDF-15 (HR 1.30; CI95% 1.05-1.62; p = 0.017), GAL-3 (HR 1.29; CI95% 1.03-1.61; p = 0.029), ST-2 (HR 1.48; CI95% 1.18-1.85; p < 0.001), and MMP-3 (HR 1.33; CI95% 1.09-1.63; p = 0.006). None of the proteins showed any significant association with re-hospitalization risk. In this study, we were able to demonstrate that elevated levels of three plasma proteins previously linked to myocardial fibrosis are associated with prevalent AF in a HF population. Additionally, higher levels of five plasma proteins yielded an increased risk of mortality in the HF population with or without co-existing AF.

Neuroprotective Effect of Exogenous Galectin-1 in Status Epilepticus.

Intrahippocampal pilocarpine microinjection (H-PILO) induces status epilepticus (SE) that can lead to spontaneous recurrent seizures (SRS) and neurodegeneration in rodents. Studies using animal models have indicated that lectins mediate a variety of biological activities with neuronal benefits, especially galectin-1 (GAL-1), which has been identified as an effective neuroprotective compound. GAL-1 is associated with the regulation of cell adhesion, proliferation, programmed cell death, and immune responses, as well as attenuating neuroinflammation. Here, we administrated GAL-1 to Wistar rats and evaluated the severity of the SE, neurodegenerative and inflammatory patterns in the hippocampal formation. Administration of GAL-1 caused a reduction in the number of class 2 and 4 seizures, indicating a decrease in seizure severity. Furthermore, we observed a reduction in inflammation and neurodegeneration 24h and 15days after SE. Overall, these results suggest that GAL-1 has a neuroprotective effect in the early stage of epileptogenesis and provides new insights into the roles of exogenous lectins in temporal lobe epilepsy(TLE).