Immune Proteins Research Articles

Distinct phenotypes of salivaricin-producing Ligilactobacillus salivarius isolated from the gastrointestinal tract of broiler chickens and laying hens: SALIVARICIN-PRODUCING LIGILACTOBACILLUS SALIVARIUS

Ligilactobacillus salivarius harbors bacteriocin genes in its repA-type megaplasmid, specifically salivaricin P (salP), a class IIb bacteriocin. This study aimed to differentiate 25 salP-positive Lig. salivarius strains isolated from the gastrointestinal tract (GIT) of broilers and laying hens. Results showed that 12 isolates were classified as Type A, with active bacteriocins, while the rest were Type B, with no active bacteriocins. In vitro and in silico characterization of salP bacteriocins revealed narrow-spectrum antibacterial activity against Listeria monocytogenes and Enterococcus faecalis. SalP bacteriocins were predicted as positively-charged, hydrophobic, small molecular weight (α, 4.097 kDa; ß, 4.285 kDa) bacteriocins with characteristic GXXXG motif. Investigation of the salP gene cluster based on genomic data revealed that Type B strains lacked the lanT and hlyD genes that encode export proteins dedicated to the modification and extracellular transport of mature salP peptides. However, two Type B strains (B4311 and B5258) showed inhibitory activity against L. monocytogenes ATCC19114. Multiplex PCR analysis and synteny mapping analysis revealed that B4311 and B5258 strains harbored the lanT gene, highlighting the importance of LanT protein in the cleavage of leader peptide and excretion of mature peptides. Further analysis revealed that the resistance of Type B strains to salP was attributable to the presence of a dedicated immunity protein, blurring the evolutionary significance of producing active bacteriocins for competitive advantage. Additionally, the loss of export proteins occurred in a polyphyletic manner, consistent with the genetic plasticity of the repA-type megaplasmid. This suggests that the loss of lanT and hlyD is likely in the presence of limited nutritional competitors. In conclusion, the observed differences in salivaricin production of Lig. salivarius exists independent of isolation host and that Type A and Type B strains can co-exist in the same environment. Finally, the functional characterization of active salP allows for a better understanding of its potential to control specific bacteria in human food and animal production.

A small microcin plays a big role in V. cholerae interbacterial competition

Microcins are antibacterial small proteins secreted by gram-negative bacteria. In this issue of Cell Host & Microbe, Kim etal. report the discovery of a V.cholerae microcin, MvcC. MvcC shows antibacterial activity against non-self V.cholerae strains, which do not encode the cognate immunity protein.

The antibacterial activity of a prophage-encoded fitness factor is neutralized by two cognate immunity proteins

The antibacterial activity of a prophage-encoded fitness factor is neutralized by two cognate immunity proteins

Compression force promotes glioblastoma progression through the Piezo1‑GDF15‑CTLA4 axis.

Glioma, a type of brain tumor, is influenced by mechanical forces in its microenvironment that affect cancer progression. However, our understanding of the contribution of compression and its associated mechanisms remains limited. The objective of the present study was to create an environment in which human brain glioma H4 cells experience pressure and thereby investigate the compressive mechanosensors and signaling pathways. Subsequent time‑lapse imaging and wound healing assays confirmed that 12 h of compression significantly increased cell migration, thereby linking compression with enhanced cell motility. Compression upregulated the expression of Piezo1, a mechanosensitive ion channel, and growth differentiation factor 15 (GDF15), a TGF‑β superfamily member. Knockdown experiments targeting PIEZO1 or GDF15 using small interfering RNA resulted in reduced cell motility, with Piezo1 regulating GDF15 expression. Compression also upregulated CTLA4, a critical immune checkpoint protein. The findings of the present study therefore suggest that compression enhances glioma progression by stimulating Piezo1, promoting GDF15 expression and increasing CTLA4 expression. Thus, these findings provide important insights into the influence of mechanical compression on glioma progression and highlight the involvement of the Piezo1‑GDF15 signaling pathway. Understanding tumor responses to mechanical forces in the brain microenvironment may guide the development of targeted therapeutic strategies to mitigate tumor progression and improve patient outcomes.

Soluble immune checkpoints associated with disease activity and treatment response in GD and TED.

Soluble immune checkpoints play an important role in peripheral tolerance that has seldom been investigated in Graves' disease (GD) and thyroid eye disease (TED). The objective of this work is to examine the alteration of soluble immune checkpoints in GD and TED. We performed a quantitative multiplex analysis of 17 immune checkpoint proteins in serum from 50 GD patients without TED, 28 GD patients with TED and 40 healthy controls. The association with demographical, serological, clinical features and 27 cytokines was analyzed. A follow-up was conducted in GD patients without TED. Functional outcomes of sLAG-3 and sGITR were assessed in cell cultures using rh-LAG3, rh-GITR, an antagonistic LAG-3 antibody and an antagonistic GITR antibody. GD patients with TED had distinct sICP and cytokine profiles compared with GD patients without TED. Active TED patients exhibited elevation in the levels of sBTLA, sLAG-3, sGITR, sCD80, sCD86 and sPD-L1. Further, GD patients without TED with high sBTLA, sCD27 and sCD40 levels at baseline showed a better improvement in thyrotropin receptor antibody (TRAb) titers after antithyroid drug (ATD) treatment. Adding recombinant human GITR and LAG-3 to PBMC cultures resulted in increased inflammatory cytokine secretion and decreased anti-inflammatory cytokine secretion. The present study uncovers disturbed soluble immune checkpoints and cytokines in GD patients with and without TED, and may pave the way for novel immunological screening, allowing for identification of TED patients at higher risk of developing active disease and GD patients with better treatment response after ATD treatment.

Development of a PD-L1 Overexpression System in HEK293T Cells: A Platform for Studying Immune Evasion Mechanisms

Programmed death-ligand 1 (PD-L1) is a key immune checkpoint protein that facilitates tumor immune evasion by interacting with PD-1 receptors on T cells, making the PD-1/PD-L1 axis a critical target in cancer immunotherapy. However, resistance to these therapies remains a challenge, necessitating further exploration of PD-L1’s functions and regulatory mechanisms. In this study, we amplified the PD-L1 coding sequence (CDS) from human cDNA, cloned it into a pcDNA3.1 vector, and transfected it into HEK293T cells to establish a robust in vitro PD-L1 overexpression system. Quantitative RT-qPCR demonstrated a 300-400 fold increase in PD-L1 mRNA expression compared to controls. These results confirm the successful construction of the PD-L1 overexpression plasmid and validate its application as a tool for studying PD-L1’s role in immune modulation and its potential implications in overcoming resistance to immunotherapy. This system provides a valuable platform for future investigations into PD-L1-mediated mechanisms of immune evasion and cancer progression.

Low plasma levels of BTLA and LAG-3 before HCV therapy are associated with metabolic disorders after HCV eradication in persons with HIV/HCV coinfection: a retrospective study.

Understanding the predictors of metabolic disorders in persons with HIV/HCV coinfection post-HCV therapy is crucial for improving patient outcomes. Since immune checkpoint proteins are usually upregulated in these persons with HIV/HCV coinfection, we aimed to evaluate the association between plasma immune checkpoint proteins at baseline (before HCV therapy) and metabolic disturbances during the follow-up (about 5years after successful HCV treatment) in persons with HIV/HCV coinfection. We performed a retrospective study on 80 persons with HIV/HCV coinfection with advanced fibrosis or cirrhosis who cleared HCV infection after successful HCV therapy and were followed for about 5 years after completion of HCV treatment. Plasma samples were collected at baseline. Immune checkpoint proteins were analyzed using a Luminex 200™ analyzer. Outcomes were the development of a metabolic event (type 2 diabetes mellitus and/or dyslipidemia) and the change in Triglycerides and glucose (TyG) index. During follow-up, 21 (26%) patients developed metabolic events (type 2 diabetes mellitus/dyslipidemia), and 29 (46.0%) patients had an increase in TyG during the follow-up. Low baseline values of BTLA and LAG-3, two immune checkpoint proteins, were associated with the development of metabolic events (aAMR = 0.69 and aAMR = 0.71, respectively) and with increases in TyG values (aAMR = 0.72 and aAMR = 0.70, respectively). In addition, other immune checkpoint proteins were also inversely associated with increases in TyG. We discovered that low plasma levels of BTLA and LAG-3 before HCV therapy significantly correlate with an increased risk of developing metabolic disorders after treatment.

Immunoproteomics: Approach to Diagnostic and Vaccine Development.

The study of large protein sets (proteomics) involved in the immunological reaction is known as immunoproteomics. The methodology of immunoproteomics plays a major role in identifying possible vaccine candidates that could protect against pathogenic infection. The study of immunogenic proteins that are expressed during the outset of infection is the focus of the crosstalk between proteomics and immune protection antigens utilizing serum. Peptide presentation by MHC provides the new 'window' into changes that occur in the cell. Thus, there is strong, intense pressure on the pathogen that has been mutated in such an unusual manner that it can bypass the MHC peptide presentation by the MHC molecule. The pathogen's ability to evade the immune system is strongly restricted by the two unique distinct properties of MHC molecules, i.e., polygenic and polymorphic properties. MHC-I restriction epitope identification has traditionally been accomplished using genetic motif prediction. The study of immune system proteins and their interactions is the main emphasis of the specialist field of immunoproteomics within proteomics. Methodologies include mass spectrometry (MS), SRM assay, MALDI-TOF, Chromatography, ELISA, 2DG PAGE, and bioinformatics tools. Challenges are the complexity of the immune system, protein abundance and dynamics, sample variability, post-translational modifications (PTMs), and data integration. Current advancements are enhanced mass spectrometry techniques, single-cell proteomics, artificial intelligence and machine learning, advanced protein labeling techniques, integration with other omics technologies, and functional proteomics. However, the recently emerging field of immunoproteomics has more promising possibilities in the field of peptide-based vaccines and virus-like particle vaccines. The importance of immunoproteomics technologies and methodologies, as well as their use in the field of vaccinomics, are the main topics of this review. Here, we have discussed immunoproteomics in relation to a step towards the future of vaccination.

Immunohistochemical Expression of Immune Regulatory Proteins in Interface Dermatoses.

Cutaneous immune-related adverse events (irAEs) of immunotherapies, such as anti-programmed cell death protein-1 (PD-1), suggest that immune checkpoint factors may contribute to the pathobiology of lichenoid interface dermatitis in immunotherapy-naïve patients. Our study aimed to describe innate and adaptive immune markers via immunohistochemical (IHC) staining of lichenoid interface dermatoses. We studied the staining patterns of PD-L1, STING, IL-36 gamma, CD8, PD-1, and LAG-3 in five interface dermatoses: oral lichen planus (LP) (n = 10), cutaneous LP (n = 10), chronic cutaneous lupus erythematosus (CLE) (n = 11), erythema multiforme (EM) (n = 11), and toxic epidermal necrolysis (TEN) (n = 13), by immunohistochemistry (IHC) analysis. Expression was evaluated semi-quantitively according to the percentage of keratinocytes and dermal lymphocytes stained compared to keratinocytes and resident pericapillary lymphocytes in normal human skin. All interface dermatoses evaluated showed increased expression of PD-L1 on keratinocytes and LAG-3 in lymphocytes. STING was increased on the keratinocytes of most specimens. Expression of IL-36 gamma, in basal layer keratinocytes was more extensive in oral LP and cutaneous LP and varied in CLE, EM, and TEN. Lymphocytic infiltration expressing PD-1 was elevated in oral LP, cutaneous LP, and CLE. Current thinking is that interface dermatitis is the result of a cell-mediated immune reaction involving cytotoxic CD8+ T-cell-mediated apoptosis of keratinocytes. The findings of this study suggest that in addition to cell-mediated immunity, innate immune factors may contribute to pathobiology.

Antibody blockade of the PSGL-1 immune checkpoint enhances T-cell responses to B-cell lymphoma.

Despite advancements in cancer immunotherapy, most lymphomas remain unresponsive to checkpoint inhibitors. P-selectin glycoprotein ligand-1 (PSGL-1), recently identified as a promoter of T-cell exhaustion in murine melanoma models, has emerged as a novel immune checkpoint protein and promising immunotherapeutic target. In this study, we investigated the potential of PSGL-1 antibody targeting in B-cell lymphoma. Using allogeneic co-culture systems, we demonstrated that targeted antibody interventions against human PSGL-1 enhanced T-cell activation and effector cytokine production in response to lymphoma cells. Moreover, in vitro treatment of primary lymphoma cell suspensions with PSGL-1 antibody resulted in increased activation of autologous lymphoma-infiltrating T cells. Using the A20 syngeneic B-cell lymphoma mouse model, we found that PSGL-1 antibody treatment significantly slowed tumor development and reduced the endpoint tumor burden. This antitumoral effect was accompanied by augmented tumor infiltration of CD4+ and CD8+ T cells and reduced infiltration of regulatory T cells. Finally, anti-PSGL-1 administration enhanced the expansion of CAR T cells previously transferred to mice bearing the aggressive Eμ-Myc lymphoma cells and improved disease control. These results demonstrate that PSGL-1 antibody blockade bolsters T-cell activity against B-cell lymphoma, suggesting a potential novel immunotherapeutic approach for treating these malignancies.

Impairment of spinal CSF flow precedes immune cell infiltration in an active EAE model

Accumulation of immune cells and proteins in the subarachnoid space (SAS) is found during multiple sclerosis and in the animal model experimental autoimmune encephalomyelitis (EAE). Whether the flow of cerebrospinal fluid (CSF) along the SAS of the spinal cord is impacted is yet unknown. Combining intravital near-infrared (NIR) imaging with histopathological analyses, we observed a significantly impaired bulk flow of CSF tracers within the SAS of the spinal cord prior to EAE onset, which persisted until peak stage and was only partially recovered during chronic disease. The impairment of spinal CSF flow coincided with the appearance of fibrin aggregates in the SAS, however, it preceded immune cell infiltration and breakdown of the glia limitans superficialis. Conversely, cranial CSF efflux to cervical lymph nodes was not altered during the disease course. Our study highlights an early and persistent impairment of spinal CSF flow and suggests it as a sensitive imaging biomarker for pathological changes within the leptomeninges.

Toxoplasma gondii ROP5 Enhances Type I IFN Responses by Promoting Ubiquitination of STING.

Toxoplasma gondii is a widely spread opportunistic pathogen that can infect nearly all warm-blooded vertebrates and cause serious toxoplasmosis in immunosuppressed animals and patients. However, the relationship between the host's innate immune system and effector proteins is poorly understood, particularly with regard to how effectors antagonize cGAS-STING signaling during T. gondii infection. In this study, the ROP5 from the PRU strain of T. gondii was found to promote cGAS-STING-mediated immune responses. Mechanistically, ROP5 interacted with STING through predicted domain 2 and modulated cGAS-STING signaling in a predicted domain 3-dependent manner. Additionally, ROP5 strengthened cGAS-STING signaling by enhancing the K63-linked ubiquitination of STING. Consistently, ROP5 deficient PRU (PRUΔROP5) induced fewer type I IFN-related immune responses and replicated faster than the parental strain in RAW264.7 cells. Taken together, this study provides new insights into the mechanism by which ROP5 regulates T. gondii infection and provides new clues for strategies to prevent and control toxoplasmosis.

A percolation-type criticality threshold controls immune protein coating of surfaces.

When a material enters the body, it is immediately attacked by hundreds of proteins, organized into complex networks of binding interactions and reactions. How do such complex systems interact with a material, "deciding" whether to attack? We focus on the "complement" system of ∼40 blood proteins that bind microbes, nanoparticles, and medical devices, initiating inflammation. We show a sharp threshold for complement activation upon varying a fundamental material parameter, the surface density of potential complement attachment points. This sharp threshold manifests at scales spanning single nanoparticles to macroscale pathologies, shown here for diverse engineered and living materials. Computational models show these behaviors arise from a minimal subnetwork of complement, manifesting percolation-type critical transitions in the complement response. This criticality switch explains the "decision" of a complex signaling network to interact with a material, and elucidates the evolution and engineering of materials interacting with the body.

Immunoproteomics Reveal Different Characteristics for the Prognostic Markers of Intratumoral-Infiltrating CD3+ T Lymphocytes and Immunoscore in Colorectal Cancer

Tumor-infiltrating lymphocytes (TILs) and immunoscoring based on densities of CD3+ and CD8+ TILs are both favorable prognostic markers in colorectal cancer (CRC). However, determination of the molecular features of TILs, particularly their immunoproteomic signatures would require the development of large scale in situ spatiotemporal technologies. Recently, a multiplex in situ digital spatial proteomic profiling (DSP) tool GeoMx DSP has been applied to identify biomarkers predictive of therapeutic responses and to understand disease mechanisms and progression. Taking advantage of this tool, we simultaneously characterized the spatial distribution and interactions of 42 immune proteins in tumor cells (TCs), CD3+ T stromal TILs (sTILs), and CD20+ B sTILs using tissue microarrays, and further studied their associations with CD3+ T TILs and immunoscores in CRC. First, our data showed that well-known immune checkpoints, such as PD-L1, PD-L2, and LAG3, were expressed at low levels, whereas some other immune proteins, such as CD11c, CD68, STING, and CD44, were highly expressed. Second, 8 spatial interactions were identified, including 5 interactions between TC and CD20+ B sTILs, 2 interactions between CD3+ T sTILs and CD20+ B sTILs, and 1 interaction among TC, CD3+ T sTILs, and CD20+ B sTILs. Third, the differential immune microlandscape in the spatial compartments was identified in tissues with positive CD3+ T intratumoral TILs and high immunoscores. Collectively, to our knowledge, our study is the first to provide in situ spatial immune characteristics at the proteomic level. Moreover, our findings provide direct evidence supporting the infiltration of CD3+ T sTILs from stoma to TC and shed important insights into better understanding and treating CRC patients related to different immune prognostic markers.

Discovery of small molecules for autophagy-lysosome degradation of immune checkpoint proteins

Targeted protein degradation (TPD) technologies, particularly proteolysis targeting chimeras (PROTACs), have emerged as a promising branch of targeted therapy. Current ubiquitin-proteasome-dependent TPD technologies are limited to targeting intracellular proteins. Although the blockade of immune checkpoints has achieved great clinical success, most immune checkpoints are transmembrane proteins, which are difficult to be ubiquitinated and degraded by PROTACs. Herein, we developed a novel discovery strategy of bifunctional small molecules, which could mediate autophagy-lysosome degradation of immune checkpoints. F-1 was demonstrated to activate the autophagy-lysosome system, and conjugation of F-1 with inhibitors targeting programmed cell death-ligand 1 (PD-L1) or V-domain Ig suppressor of T-cell activation (VISTA) generated a new class of small molecules that effectively induce the degradation of PD-L1 or VISTA in tumor cells. The most promising PD-L1 degrader B3 significantly induced PD-L1 degradation in RKO cells through the autophagy-lysosome system and exhibited good tumor-inhibiting effects in vivo. Our work could expand the development of degraders targeting immune checkpoints and provide a promising discovery strategy for future autophagy-lysosome targeting degradation technology.

Farm exposure is associated with human breast milk immune profile and microbiome.

Prenatal and early life farm exposure, and breastfeeding, are associated with protection from allergic diseases. We hypothesize that farm exposure influences the human breast milk microbiome and immune proteins. The immune protein profiles and microbial communities of 152 human breast milk samples were compared among three maternal farm exposure groups (traditional agrarian, farm, and non-farm) in rural Wisconsin to identify signatures associated with farm status and atopic disease. We found significant differences between farm groups for 23 immune proteins (p-adj<0.05), microbiome diversity (p=2.2E-05), and microbiome richness (p=8.0e-06). Traditional agrarian human breast milk had the highest immune protein levels and microbiome diversity and richness, followed by farm and non-farm human breast milk. Furthermore, Gram-positive bacterial species correlated with IL-23 mediated signaling events (p-adj<1.0E-05). These data suggest that increased farm exposures promotes human breast milk that is more microbially-diverse and rich in immune-associated proteins, ultimately influencing immune development in the infant.

HLA-G expression associates with immune evasion muscle-invasive urothelial cancer and drives prognostic relevance.

Urothelial bladder cancer is frequent and exhibits diverse prognoses influenced by molecular subtypes, urothelial subtype histology, and immune microenvironments. HLA-G, known for immune regulation, displays significant membranous expression in tumor tissues. We studied the protein expression of Human Leucocyte Antigen G (HLA-G) in 241 Muscle-Invasive Bladder Cancer (MIBC) patients, elucidating its potential clinical and biological significance. Protein expression levels were evaluated and correlated with molecular subtypes, histological characteristics, immune microenvironment markers, and survival outcomes. High HLA-G expression associates with poor overall survival (OS) and diseasespecific survival (DSS), independent of clinicopathological parameters. HLA-G expression varies among molecular subtypes and Urothelial Subtype Histology, e.g., elevated expression levels in basal/squamous MIBC and those with sarcomatoid differentiation. Notably, HLA-G is increased in MIBC with an immune evasive microenvironment (high PD-L1 tumor cell expression, NK cell depletion, granzyme B (GZMB)/CD8 ratio reduction, MHC class I (MHCI) expression reduction) that are characterized by immunosuppressive features and poor prognosis. Furthermore, HLA-G correlates with elevated levels of other immune checkpoint proteins (TIGIT, LAG3, CTLA-4), indicating its role in immune evasion. Our findings underscore HLA-G's role as a potential prognostic marker and interesting immunotherapeutic target in MIBC. Its impact on immune evasion mechanisms and broad expression, coupled with associations withpoor survival and distinct tumor phenotypes, positions HLA-G as a promising protein for further exploration in developing targeted immunotherapies for MIBC patients.

Candidate Molecular Biomarkers of Traumatic Brain Injury: A Systematic Review.

Traumatic brain injury (TBI) is one of the leading causes of mortality and disability among young and middle-aged individuals. Adequate and timely diagnosis of primary brain injuries, as well as the prompt prevention and treatment of secondary injury mechanisms, significantly determine the potential for reducing mortality and severe disabling consequences. Therefore, it is crucial to have objective markers that indicate the severity of the injury. A number of molecular factors-proteins and metabolites-detected in the blood immediately after trauma and associated with the development and severity of TBI can serve in this role. TBI is a heterogeneous condition with respect to its etiology, clinical form, and genesis, being accompanied by brain cell damage and disruption of blood-brain barrier permeability. Two oppositely directed flows of substances and signals are observed: one is the flow of metabolites, proteins, and nucleic acids from damaged brain cells into the bloodstream through the damaged blood-brain barrier; the other is the infiltration of immune cells (neutrophils and macrophages) and serological proteins. Both flows aggravate brain tissue damage after TBI. Therefore, it is extremely important to study the key signaling events that regulate these flows and repair the damaged tissues, as well as to enhance the effectiveness of treatments for patients after TBI.

Mass-tagged self-assembled nanoprobe reveals the transport of PD-L1 from cancer cells to tumor-educated platelets

BackgroundThe expression level of immune checkpoint proteins detected by tissue biopsy is currently used as a predictive biomarker for immune checkpoint blockade (ICB) therapy. However, tissue biopsy is susceptible to invasive sample collection procedures, significant sampling heterogeneity, and the difficulty of repeated sampling. Therefore, liquid biopsy of blood samples is becoming an alternative choice for immune checkpoint protein detection. Among various vesicles in blood, platelets can obtain cancer information to form a specific group called tumor-educated platelets (TEPs). The platelet-derived proteins in TEPs may have a predictive potential in ICB therapy. ResultsIn this study, a photo-cleavable mass-tagged self-assembled (SAMT) nanoprobe with signal amplification was developed for the quantitative detection of PD-L1. The SAMT probe was assembled by photo-cleavable mass tags, PD-L1 aptamer, and amphiphilic polymer. After binding with PD-L1 on the platelet, the probe can release mass tags with UV light exposure. The amount of the mass tag, representing that of PD-L1, was subsequently determined by mass spectrometry. The assay sensitivity can be greatly improved by up to four orders of magnitude, achieving a detection limit of 10 fM. This assay was subsequently applied to cancer cells and platelet samples from non-small cell lung cancer (NSCLC) patients. The patients with higher tumor stages, higher degrees of lymph node invasion, and better ICB response had higher PD-L1 levels on platelets. Further investigation revealed that PD-L1 on the platelets was transported from cancer cells, providing evidence for the existence of TEPs. SignificanceThe SAMT probe can amplify the signal of the target molecule into that of multiple mass tags, achieving ultrasensitive ICB protein quantitative detection in platelets. Moreover, the employed SAMT assay not only revealed PD-L1 transport from cancer cells to platelets but also confirmed the presence of TEPs.

Effect and mechanism of novel HDAC inhibitor ZDLT-1 in colorectal cancer by regulating apoptosis and inflammation

BackgroundHistone deacetylase (HDAC) is a potential target for Colorectal Cancer (CRC) molecular target therapy, dehydroharmine derivative ZDLT-1 was designed to inhibit CRC cell proliferation by inhibiting HDAC target. This study aimed to explore the effect of ZDLT-1 could induce apoptosis in CRC in vitro and in vivo, and determine the mechanism of ZDLT-1. MethodsFirst, MTT assay, colony formation, wound healing, Transwell assay, Hoechst33342 staining and Annexin V-FITC/PI double staining assay were used to investigate the in vitro effect of ZDLT-1. Second, the toxicity and the anti-tumor effect of ZDLT-1 by subcutaneous tumorigenesis assay were used to determine the in vivo effect of ZDLT-1. In terms of mechanism, we evaluated the effect of ZDLT-1 on HDAC downstream proteins such as HIF-1α, NF-κB, Cleaved-Caspase-3/9, GSDMD and acetylated histone by immunofluorescence and Western blot assessments. ResultsThis study confirmed that ZDLT-1 had anti-tumor activity by inhibiting cell proliferation in vitro and solid tumor growth in vivo. Furthermore, ZDLT-1 can inhibit CRC cell invasion, migration and apoptosis in vitro. Moreover, ZDLT-1 can promote the expression of apoptosis proteins in HIF-1α/Caspase-3/Caspase-9 pathway and inhibit the expression of tumor-related immune proteins mainly in NF-κB/GSDMD/GSDME pathway. ConclusionZDLT-1 as HDAC inhibitor could suppresses CRC cell growth in vivo and in vitro by triggering HIF-1α/Caspase-3/Caspase-9 pathway in promoting apoptosis, and triggering NF-κB/GSDMD/GSDME pathway in inhibiting tumor inflammation. Our results propose dehydroharmine derivative ZDLT-1 as a promising therapeutic small molecular agent for CRC.