The Paradoxical Roles of Inflammation during PD-1 Blockade in Cancer

PD-1: A critical player and target for immune normalization

Immune system imbalances contribute to the pathogenesis of several different diseases, and immunotherapy shows great therapeutic efficacy against tumours and infectious diseases with immune-mediated derivations. In recent years, molecules targeting the programmed cell death protein 1 (PD-1) immune checkpoint have attracted much attention, and related signalling pathways have been studied clearly. At present, several inhibitors and antibodies targeting PD-1 have been utilized as anti-tumour therapies. However, increasing evidence indicates that PD-1 blockade also has different degrees of adverse side effects, and these new explorations into the therapeutic safety of PD-1 inhibitors contribute to the emerging concept that immune normalization, rather than immune enhancement, is the ultimate goal of disease treatment. In this review, we summarize recent advancements in PD-1 research with regard to immune normalization and targeted therapy.

Preclinical development and clinical studies of targeted JAK/STAT combined Anti-PD-1/PD-L1 therapy

Programmed cell death protein 1 (PD-1) binds to its ligand to help tumours evade the immune system and promote tumour progression. Although anti-PD-1/PD-L1 therapies show powerful effects in some patients, most patients are unable to benefit from this treatment due to treatment resistance. Therefore, it is important to overcome tumour resistance to PD-1/PD-L1 blockade. There is substantial evidence suggesting that the JAK/STAT signalling pathway plays a significant role in PD-1/PD-L1 expression and anti-PD-1/PD-L1 treatment. Herein, we describe the effects of the JAK/STAT signalling pathway on PD-1/PD-L1. Subsequently, the relationship between molecular mutations in the JAK/STAT signalling pathway and immune resistance was analysed. Finally, the latest advancements in drugs targeting the JAK/STAT pathway combined with PD1/PD-L1 inhibitors are summarised.

Research Progress of Nanomaterials Acting on NK Cells in Tumor Immunotherapy and Imaging

The prognosis for cancer patients has declined dramatically in recent years due to the challenges in treating malignant tumors. Tumor immunotherapy, which includes immune target inhibition and chimeric antigen receptor cell treatment, is currently evolving quickly. Among them, natural killer (NK) cells are gradually becoming another preferred cell immunotherapy after T cell immunotherapy due to their unique killing effects in innate and adaptive immunity. NK cell therapy has shown encouraging outcomes in clinical studies; however, there are still some problems, including limited efficacy in solid tumors, inadequate NK cell penetration, and expensive treatment expenses. Noteworthy benefits of nanomaterials include their chemical specificity, biocompatibility, and ease of manufacturing; these make them promising instruments for enhancing NK cell anti-tumor immune responses. Nanomaterials can promote NK cell homing and infiltration, participate in NK cell modification and non-invasive cell tracking and imaging modes, and greatly increase the effectiveness of NK cell immunotherapy. The introduction of NK cell-based immunotherapy research and a more detailed discussion of nanomaterial research in NK cell-based immunotherapy and molecular imaging will be the main topics of this review.

Regulators of G-Protein Signaling (RGS) in Sporadic and Colitis-Associated Colorectal Cancer

Colorectal cancer (CRC) is one of the most common neoplasms worldwide. Among the risk factors of CRC, inflammatory bowel disease (IBD) is one of the most important ones leading to the development of colitis-associated CRC (CAC). G-protein coupled receptors (GPCR) are transmembrane receptors that orchestrate a multitude of signaling cascades in response to external stimuli. Because of their functionality, they are promising targets in research on new strategies for CRC diagnostics and treatment. Recently, regulators of G-proteins (RGS) have been attracting attention in the field of oncology. Typically, they serve as negative regulators of GPCR responses to both physiological stimuli and medications. RGS activity can lead to both beneficial and harmful effects depending on the nature of the stimulus. However, the atypical RGS-AXIN uses its RGS domain to antagonize key signaling pathways in CRC development through the stabilization of the β-catenin destruction complex. Since AXIN does not limit the efficiency of medications, it seems to be an even more promising pharmacological target in CRC treatment. In this review, we discuss the current state of knowledge on RGS significance in sporadic CRC and CAC with particular emphasis on the regulation of GPCR involved in IBD-related inflammation comprising opioid, cannabinoid and serotonin receptors.

Interplay between inflammasomes and PD-1/PD-L1 and their implications in cancer immunotherapy

The inflammasomes play crucial roles in inflammation and cancer development, while the PD-1/PD-L1 pathway is critical for immune suppression in the tumor microenvironment (TME). Recent research indicates a reciprocal regulatory relationship between inflammasomes and PD-1/PD-L1 signaling in cancer development and PD-1 blockade treatment. By activating in diverse cells in tumor tissues, inflammasome upregulates PD-L1 level in the TME. Moreover, the regulation of PD-1/PD-L1 activity by inflammasome activation involves natural killer cells, tumor-associated macrophages and myeloid-derived suppressor cells. Conversely, PD-1 blockade can activate the inflammasome, potentially influencing treatment outcomes. The interplay between inflammasomes and PD-1/PD-L1 has profound and intricate effects on cancer development and treatment. In this review, we discuss the crosstalk between inflammasomes and PD-1/PD-L1 in cancers, exploring their implications for tumorigenesis, metastasis and immune checkpoint inhibitor (ICI) resistance. The combined therapeutic strategies targeting both inflammasomes and checkpoint molecules hold promising potential as treatments for cancer.

Timing of Adjuvant Immunotherapy in Stage III Melanoma, Does it Matter?

BACKGROUND

The optimal time to initiate adjuvant immune checkpoint inhibitors (ICI) following resection remains undefined. Herein, we investigated the impact of time to adjuvant ICI on survival in patients with stage III melanoma.

METHODS

Patients with resected stage III melanoma receiving adjuvant immune therapy were identified within a multi-institutional retrospective cohort. Patients were stratified by time to adjuvant ICI: within 6 weeks, 6-12 weeks, and greater than 12 weeks from surgery. Recurrence-free survival (RFS) was compared among time strata with Kaplan-Meier and Cox proportional hazards methods in the multi-institutional cohort.

RESULTS

Altogether, 626 patients were identified within the multi-institutional cohort: 39% of patients initiated adjuvant ICI within 6 weeks, 42.2% within 6-12 weeks, and 18.8% greater than 12 weeks from surgery. In a multivariate Cox model, adjusting for histology, nodal tumor burden, and pathologic stage, we found that increased time to adjuvant ICI was associated with improved RFS. Patients who initiated adjuvant ICI within 6 weeks of surgery had worse RFS. These findings were preserved in a conditional landmark analysis and separate subgroups of patients with (1) new melanoma diagnoses, (2) occult stage III disease, and (3) those receiving anti-PD-1 monotherapy.

CONCLUSIONS

Outcomes for patients with stage III melanoma are not compromised when adjuvant ICI is initiated beyond 6 weeks from resection. Additional work is needed to better understand the underlying mechanisms and implications of timing of adjuvant ICI on long-term outcomes.

JK5G postbiotics attenuate immune-related adverse events in NSCLC patients by regulating gut microbiota: a randomized controlled trial in China

Scope

This study aimed to evaluate the effects of JK5G postbiotics to regulate imbalanced gut microbiota and its impacts on the efficacy and incidence rate of immune-related adverse events (irAEs) in non-small-cell lung cancer (NSCLC) patients treated with immune checkpoint inhibitors (ICIs).

Methods

This randomized, double-blind, placebo-controlled trial was conducted in China and included non-squamous or squamous NSCLC patients without EGFR, ROS1, and ALK alteration, treatment-naive, and stage IIIb-IV. Patients were randomly (1:1) divided into two groups to receive four cycles (three weeks for each cycle) of programmed cell death-1 (PD-1) plus chemotherapy plus placebo (control group, n = 30) or to receive PD-1 plus chemotherapy plus JK5G postbiotics (JK5G group, n = 30). The primary endpoint was objective response rate. The secondary endpoints were quality of life (QoL), adverse effects, and the 16S DNA sequencing of gut microbiota, blood inflammatory cytokines, and lymphocyte subsets. This study was registered at www.chictr.org.cn (ChiCTR2200064690).

Results

Sixty patients were enrolled. The objective response rate was 36.67% (11/30) in the control group and 50.00% (15/30) in the JK5G group (p = 0.297). The JK5G group had better QoL and nutritional levels, as well as lower depression symptoms than the control group (all p < 0.05). Moreover, the JK5G group had a lower incidence of anemia (63.33% vs. 13.33%, p < 0.001), decreased lymphocyte count (20.00% vs. 0%, p = 0.010), decreased appetite (53.33% vs. 16.67%, p = 0.003), nausea (33.33% vs. 6.67%, p = 0.010), and asthenia (30.00% vs. 6.67%, p = 0.017) than the control group. Moreover, JK5G attenuated gut microbiota imbalance, accompanied by increased Faecalibacterium, Ruminococcaceae, and fecal butyrate concentration, and diminished Escherichia-Shigella. Furthermore, JK5G administration significantly decreased the levels of pro-inflammatory markers, including TNF-α, IL-2, and C-reactive protein (CRP) (all p < 0.05). Significant increases in CD3+CD4+ T cells and CD4/CD8 ratio were observed in the peripheral blood of JK5G group patients (all p < 0.05). The enterotype data showed that patients were clustered into Blautia (E1) and Escherichia-Shigella (E2) enterotypes, and JK5G postbiotics intervention might be related to enterotype modulations.

Conclusion

Our current findings indicated that JK5G postbiotics might attenuate irAEs, and enhance the QoL and nutrition levels of advanced NSCLC patients who received ICIs. JK5G postbiotics could also improve the gut microbiota structures and ameliorate the tumor microenvironment and inflammation.

Clinical trial registration

www.chictr.org.cn, identifier ChiCTR2200064690.

Predictive impact of prognostic nutritional index in patients with cancer treated with immune checkpoint inhibitors: a systematic review and meta-analysis

A few previous studies have investigated the prognostic value of the prognostic nutritional index (PNI) in patients treated with immune checkpoint inhibitors (ICIs); however, the results are inconsistent. Therefore, this study aimed to clarify the prognostic significance of PNI. The PubMed, Embase, and Cochrane Library databases were searched. A meta-analysis of the impact of PNI on overall survival (OS), progression-free survival (PFS), objective response rate (ORR), disease control rate (DCR), and rate of adverse events (AEs) in patients treated with ICIs was performed. Twenty-three studies involving 2,386 patients were included. Low PNI was associated with significantly poor OS (hazard ratio [HR] = 2.26, 95% confidence interval [CI]: 1.81-2.82, P < .001) and short PFS (HR = 1.75, 95% CI: 1.54-1.99, P < .001). Patients with low PNI tended to have a low ORR (odds ratio [OR] = 0.47, 95% CI: 0.34-0.65, P < .001) and DCR (OR = 0.43, 95% CI: 0.34-0.56, P < .001). However, the subgroup analysis demonstrated no significant association between PNI and survival time in patients receiving a programmed death ligand-1 inhibitor. PNI was significantly associated with survival time and treatment efficacy in patients treated with ICIs.

The intracellular cation channel TMEM176B as a dual immunoregulator

Characterizing immune regulatory pathways is critical to understand physiological and pathophysiological processes as well as to identify novel immunotherapeutic targets. The cation channel TMEM176B has emerged in the last years as a potential new immunoregulatory player and pharmacological target. Here, we review how expression data, clinical associations of genetic variants and functional studies support a dual role for TMEM176B in regulating immune responses. Thus, TMEM176B can inhibit effector immune responses in some settings whereas it may also promote immunity by supporting antigen presentation in others. We also discuss a potential role for TMEM176B in regulating type 2 and 3 immunity and comment recent data on modulation of DC biology and inflammasome activation as well as CD8⁺ T cell responses. Understanding the role of TMEM176B in immunity is critical to propose rational pharmacological approaches targeting this channel.

Therapeutic Targets and Prognostic Biomarkers Among CXC Chemokines in Pancreatic Ductal Adenocarcinoma Microenvironment

OBJECTIVES

Pancreatic ductal adenocarcinoma (PDAC) is characterized by occult onset, rapid progression, and poor prognosis. CXC chemokines play an important role in tumor microenvironment and development. However, the potential mechanistic values of CXC chemokines as clinical biomarkers and therapeutic targets in PDAC have not been fully clarified.

METHODS

The altered expression, interaction network, and clinical data of CXC chemokines in patients with PDAC were analyzed by the data from the Gene Expression Omnibus and the Tumor Cancer Genome Atlas.

RESULTS

CXCL5 transcriptional level was significantly elevated in PDAC tissues. A significant correlation was found between the expression of CXC1/3/5/8 and the pathological stage of PDAC patients. The PDAC patients with low transcriptional levels of CXCL5/9/10/11/17 were associated with a significantly better prognosis. The functions of differentially expressed CXC chemokines are primarily related to the chemokine signaling pathway, cytokine-cytokine receptor interaction, and viral protein interaction with cytokine and cytokine receptor. RELA, NFKB1, and SP1 are key transcription factors for CXC chemokines, and the SRC family of tyrosine kinases, mitogen-activated protein kinases, CDK5, PRKCQ, ROCK1, ITK, IKBKE, JAK3, and NTRK2 are CXC chemokine targets.

CONCLUSIONS

The results indicated that CXC chemokines might serve as therapeutic targets and prognostic biomarkers in PDAC.

PD-1/PD-L1 blockade abrogates a dysfunctional innate-adaptive immune axis in critical β-coronavirus disease

Severe COVID-19 is associated with hyperinflammation and weak T cell responses against SARS-CoV-2. However, the links between those processes remain partially characterized. Moreover, whether and how therapeutically manipulating T cells may benefit patients are unknown. Our genetic and pharmacological evidence demonstrates that the ion channel TMEM176B inhibited inflammasome activation triggered by SARS-CoV-2 and SARS-CoV-2-related murine β-coronavirus. Tmem176b^-/- mice infected with murine β-coronavirus developed inflammasome-dependent T cell dysfunction and critical disease, which was controlled by modulating dysfunctional T cells with PD-1 blockers. In critical COVID-19, inflammasome activation correlated with dysfunctional T cells and low monocytic TMEM176B expression, whereas PD-L1 blockade rescued T cell functionality. Here, we mechanistically link T cell dysfunction and inflammation, supporting a cancer immunotherapy to reinforce T cell immunity in critical β-coronavirus disease.

Therapeutic targets and biomarkers of tumor immunotherapy: response versus non-response

Cancers are highly complex diseases that are characterized by not only the overgrowth of malignant cells but also an altered immune response. The inhibition and reprogramming of the immune system play critical roles in tumor initiation and progression. Immunotherapy aims to reactivate antitumor immune cells and overcome the immune escape mechanisms of tumors. Represented by immune checkpoint blockade and adoptive cell transfer, tumor immunotherapy has seen tremendous success in the clinic, with the capability to induce long-term regression of some tumors that are refractory to all other treatments. Among them, immune checkpoint blocking therapy, represented by PD-1/PD-L1 inhibitors (nivolumab) and CTLA-4 inhibitors (ipilimumab), has shown encouraging therapeutic effects in the treatment of various malignant tumors, such as non-small cell lung cancer (NSCLC) and melanoma. In addition, with the advent of CAR-T, CAR-M and other novel immunotherapy methods, immunotherapy has entered a new era. At present, evidence indicates that the combination of multiple immunotherapy methods may be one way to improve the therapeutic effect. However, the overall clinical response rate of tumor immunotherapy still needs improvement, which warrants the development of novel therapeutic designs as well as the discovery of biomarkers that can guide the prescription of these agents. Learning from the past success and failure of both clinical and basic research is critical for the rational design of studies in the future. In this article, we describe the efforts to manipulate the immune system against cancer and discuss different targets and cell types that can be exploited to promote the antitumor immune response.

Prognostic value of inflammation-immunity-nutrition score in patients with hepatocellular carcinoma treated with anti-PD-1 therapy

BACKGROUND

There are no validated biomarkers that can predict the clinical benefit of immune checkpoint blockers against the programmed cell death protein 1 (PD-1) treatments in hepatocellular carcinoma (HCC). This study aimed to investigate the prognostic value of inflammation-immunity-nutrition score (IINS) in patients with HCC treated with anti-PD-1 therapy.

METHODS

A consecutive series of 101 HCC patients treated with PD-1 inhibitors in Sichuan Provincial People's Hospital between January 2018 and August 2020 were enrolled in the retrospective study. IINS (0-6) was constructed based on pretreatment high-sensitivity C-reactive protein (hsCRP), lymphocyte (LYM), and albumin (ALB). The patients were divided into high and low IINS groups according to IINS values. Prognostic values of each variable were evaluated with univariate and multivariate time-dependent Cox regression analyses. Survival curves were calculated and compared using the Kaplan-Meier method and log-rank test. The prognostic performance of IINS was further compared with that of other traditional prognostic indicators by receiver operating characteristic (ROC) curve and the areas under the ROC curve.

RESULTS

Patients with low IINS had longer overall survival (OS) (HR: 4.711, 95% CI: 1.80-12.37, p = .001) and progression-free survival (HR: 3.411, 95% CI: 1.79-6.51, p < .0001) than those with high IINS. The multivariate analysis identified IINS (HR: 3.746, 95% CI: 1.05-13.38, p = .042) and tumor number (HR: 5.111, 95% CI: 1.075-24.299, p = .04) as independent prognostic factors. According to ROC analysis, IINS (AUC =0.729, 95% CI: 0.597-0.861, p = .002) presented better prognostic performance than other traditional prognostic indicators. The area of the IINS-CA19-9 under the ROC curve (AUC) was higher than that of the IINS or CA19-9 levels for the prediction of OS.

CONCLUSION

The results suggest that IINS may be an independent prognostic indicator for HCC patients treated with anti-PD-1 therapy. IINS-CA19-9 classification may be more effective in predicting clinical benefit of anti-PD-1 therapy in HCC patients.

Prognosis and Sensitivity of Adjuvant Chemotherapy in Mucinous Colorectal Adenocarcinoma without Distant Metastasis

In colorectal cancer, whereas mucinous adenocarcinoma (MAC) has several poor clinical prognostic factors compared to adenocarcinoma (AC), the prognosis of MAC remains controversial. We evaluated the prognosis of MAC without distant metastasis and the effects of adjuvant chemotherapy using health insurance registry data managed by South Korea. Patients with colorectal cancer between January 2014 and December 2016 were included (AC, 22,050 [96.8%]; MAC, 729 [3.2%]). We observed no difference in overall survival (OS) between AC and MAC in stages I and II. However, MAC showed a worse OS than AC in stage III disease, especially in patients administered chemotherapy (p < 0.001). These findings persisted after propensity score matching of clinical characteristics between AC and MAC. In addition, transcriptome analysis of The Cancer Genome Atlas (TCGA) data showed increased chemoresistance-associated pathways in MAC compared to AC. In consensus molecular subtypes (CMS) classification, unlike in AC, CMSs 1, 3, and 4 comprised most of MAC and the proportions of CMSs 3 and 4 increased with stage progression. These results suggest clues to overcome resistance to chemotherapy and develop targeted treatments in MAC.

Diagnostic and Prognostic Implications of Caspase-1 and PD-L1 Co-Expression Patterns in Myelodysplastic Syndromes

Simple Summary

Myelodysplastic syndromes (MDS) originate from mutated hematopoietic stem and progenitor cells. Despite recent advances in genetics, the mechanisms involved in clonal progression remain largely unknown. We performed an exploratory, case-control study to identify immune-related biomarkers with diagnostic and prognostic utility. Our study suggests a combined Casp1/PD-L1 assessment to distinguish reactive conditions from lower- and higher-risk MDS. These immune-related biomarkers may help to personalize immuno-therapies but require further validation in prospective studies.

Abstract

Background: The inflammasome plays an essential role in lower risk MDS and immune subversion, with the up-regulation of immune checkpoint molecules in the progression to higher-risk disease. In this study, we explored the utility of immune-related biomarkers for the diagnosis and prognosis of MDS. Methods: We performed an exploratory, case-control study with 20 randomly selected MDS patients and nine controls with non-inflammatory (n = 3) and inflammatory conditions (n = 6). Patients were stratified in groups of lower (n = 10) and higher risk (n = 10) using IPSS-R. For the exploration of inflammasome and immune checkpoint activities, the expression of caspase-1 (Casp1), programmed cell death protein 1 (PD-1) and its ligand (PD-L1) were assessed in bone marrow samples using immunohistochemistry. Results: In multivariate analysis, we observed significant differences for Casp1 but not PD1/PD-L1 expression in our four conditions (p = 0.003). We found a discordant co-expression of Casp1/PD-L1 in MDS (rho = −0.41, p = 0.07) compared with a concordant co-expression in controls (rho = 0.64, p = 0.06). Neutrophil counts correlated directly with Casp1 (rho = 0.57, p = 0.009) but inversely with PD-L1 expression (rho = −0.58, p = 0.007). Conclusion: We identified characteristic discordant co-expression patterns in lower- (Casp1_high/PD-L1_low) and higher-risk MDS (Casp1_low/PD-L1_high), contrasting with concordant patterns in the non-inflammatory (Casp1_low/PD-L1_low) and inflammatory conditions (Casp1_high/PD-L1_high). Further validation is warranted in larger, prospective studies.

Comparison of the Prognostic Value of Inflammation-Based Scores in Patients with Hepatocellular Carcinoma After Anti-PD-1 Therapy

Background

Inflammatory response is related to cancer progression and patient survival. However, the value in predicting survival in hepatocellular carcinoma (HCC) patients who received anti-PD-1 therapy has not been elucidated. This study aimed to compare the predictive ability of inflammation-based scores for the prognosis of HCC patients after anti-PD-1 therapy.

Methods

A total of 442 patients who received anti-PD-1 therapy were included in the study. Representative inflammation-based prognostic scores, including the platelet-to-lymphocyte ratio (PLR), neutrophil-to-lymphocyte ratio (NLR), lymphocyte-to-C-reactive protein (CRP) ratio (LCR), lymphocyte-to-monocyte ratio (LMR), systemic immune inflammation index (SII), CRP-to-albumin ratio (CAR), prognostic nutritional index (PNI), Glasgow Prognostic Score (GPS), modified Glasgow Prognostic Score (mGPS), and prognostic index (PI), were assessed for prediction accuracy using Kaplan–Meier survival curves, time-dependent receiver operating characteristic (ROC) and Harrell’s concordance index (C-index) analyses.

Results

All the inflammation-based prognostic scores exhibited good discriminatory ability in overall survival (OS) (all P < 0.01), while the PNI score was a unique independent predictor for OS in multivariate analysis (hazard ratio, 1.770; confidence interval, 1.309–2.393; P < 0.001). The areas under the ROC curves at 6, 12, 18 and 24 months and the C-index (0.65) demonstrated that the predictive accuracy of the PNI score was superior to that of the other inflammation-based scores.

Conclusion

The PNI score is a discriminatory prognostic indicator for OS in HCC patients with anti-PD-1 therapy and is superior to the other inflammation-based prognostic scores in terms of predictive ability.

Hypoxia Supports Differentiation of Terminally Exhausted CD8 T Cells

Hypoxia, angiogenesis, and immunosuppression have been proposed to be interrelated events that fuel tumor progression and impair the clinical effectiveness of anti-tumor therapies. Here we present new mechanistic data highlighting the role of hypoxia in fine-tuning CD8 T cell exhaustion in vitro, in an attempt to reconcile seemingly opposite evidence regarding the impact of hypoxia on functional features of exhausted CD8 T cells. Focusing on the recently characterized terminally-differentiated and progenitor exhausted CD8 T cells, we found that both hypoxia and its regulated mediator, vascular endothelial growth factor (VEGF)-A, promote the differentiation of PD-1+ TIM-3+ CXCR5+ terminally exhausted-like CD8 T cells at the expense of PD-1+ TIM-3- progenitor-like subsets without affecting tumor necrosis factor (TNF)-α and interferon (IFN)-γ production or granzyme B (GZMB) expression by these subpopulations. Interestingly, hypoxia accentuated the proangiogenic secretory profile in exhausted CD8 T cells. VEGF-A was the main factor differentially secreted by exhausted CD8 T cells under hypoxic conditions. In this sense, we found that VEGF-A contributes to generation of terminally exhausted CD8 T cells during in vitro differentiation. Altogether, our findings highlight the reciprocal regulation between hypoxia, angiogenesis, and immunosuppression, providing a rational basis to optimize synergistic combinations of antiangiogenic and immunotherapeutic strategies, with the overarching goal of improving the efficacy of these treatments.

Tissue-specific control of galectin-1-driven circuits during inflammatory responses

The relevance of glycan-binding protein in immune tolerance and inflammation has been well established, mainly by studies of C-type lectins, siglecs and galectins both in experimental models and patient samples. Galectins, a family of evolutionarily conserved lectins, are characterized by sequence homology in the carbohydrate-recognition domain (CRD), atypical secretion via an ER-Golgi-independent pathway and the ability to recognize β-galactoside-containing saccharides. Galectin-1 (Gal-1), a prototype member of this family displays mainly anti-inflammatory and immunosuppressive activities, although, similar to many cytokines and growth factors, it may also trigger paradoxical pro-inflammatory effects under certain circumstances. These dual effects could be associated to tissue-, time- or context-dependent regulation of galectin expression and function, including particular pathophysiologic settings and/or environmental conditions influencing the structure of this lectin, as well as the availability of glycosylated ligands in immune cells during the course of inflammatory responses. Here, we discuss the tissue-specific role of Gal-1 as a master regulator of inflammatory responses across different pathophysiologic settings, highlighting its potential role as a therapeutic target. Further studies designed at analyzing the intrinsic and extrinsic pathways that control Gal-1 expression and function in different tissue microenvironments may contribute to design tailored therapeutic strategies aimed at positively or negatively modulate this glycan-binding protein in pathologic inflammatory conditions.