Modulation Of Immune Microenvironment Research Articles

Lysyl oxidase-responsive anchoring nanoparticles for modulation of the tumor immune microenvironment

In the tumor microenvironment, lysyl oxidase (LOX) is known to play a key role in stabilizing the tumor extracellular matrix. Here, we designed LOX-responsive nanoparticles to interact with the collagen matrix of the tumor microenvironment. Collagen-coated and imiquimod-loaded polydopamine nanoparticles (CPN/IQ) could form crosslinked structures with the collagen matrix via LOX. In vitro, anchoring of CPN/IQ nanoparticles was observed with LOX-secreting CT26 cells, but this was blocked by a LOX inhibitor. In CT26 tumor-bearing mice, co-administration of nanoparticles plus the LOX inhibitor did not significantly alter the antitumor efficacy among nanoparticles. In the absence of the LOX inhibitor, however, a single administration of CPN/IQ could provide sustained responsiveness to near-infrared irradiation and ablation of primary tumors. In the primary tumor microenvironment, CPN/IQ lowered the Treg cell population but increased the cytotoxic CD3+CD8+ T cell population. In splenic dendritic cells, CPN/IQ treatment significantly increased the CD11c+CD86+ and CD11c+CD80+ cell populations. In a CT26 distant tumor-rechallenge model, CPN/IQ treatment increased the cytotoxic CD3+CD8+ T cell population and provided 100% survival of mice until 64 days. This study indicates the feasibility of tumor immune microenvironment modulation using LOX-responsive size-transforming nanoparticles. Although we tested the concept in a CT26 cell-derived tumor model, the concept of LOX-responsive collagen matrix- anchoring nanoparticles may be broadly applied to other tumor tissues with LOX-rich tumor microenvironments.

Role of Interleukins in Inflammation-Mediated Tumor Immune Microenvironment Modulation in Colorectal Cancer Pathogenesis.

Tumor cells invade and spread through a procedure termed as epithelial-to-mesenchymal cell transition (EMT). EMT is triggered by any alterations in the genes that encode the extracellular matrix (ECM) proteins, the enzymes that break down the ECM, and the activation of the genes that causes the epithelial cell to change into a mesenchymal type. The transcription factors NF-κB, Smads, STAT3, Snail, Zeb, and Twist are activated by inflammatory cytokines, for instance, Tumor Necrosis Factor, Tumor Growth Factors, Interleukin-1, Interleukin-8, and Interleukin-6, which promotes EMT. The current piece of work has been reviewed from the literature works published in last 10 years on the role interleukins in inflammation-mediated tumor immune microenvironment modulation in colorectal cancer pathogenesis utilizing the databases like Google Scholar, PubMed, Science Direct. Recent studies have demonstrated that pathological situations, such as epithelial malignancies, exhibit EMT characteristics, such as the downregulation of epithelial markers and the overexpression of mesenchymal markers. Several growing evidence have also proved its existence in the human colon during the carcinogenesis of colorectal cancer. Most often, persistent inflammation is thought to be one factor contributing to the initiation of human cancers, such as colorectal cancer (CRC). Therefore, according to epidemiologic and clinical research, people with ulcerative colitis and Crohn's disease have a greater probability of developing CRC. A substantial amount of data points to the involvement of the NF-κB system, SMAD/STAT3 signaling cascade, microRNAs, and the Ras-mitogen-activated protein kinase/Snail/Slug in the epithelial-to-mesenchymal transition-mediated development of colorectal malignancies. As a result, EMT is reported to play an active task in the pathogenesis of colorectal cancer, and therapeutic interventions targeting the inflammation-mediated EMT might serve as a novel strategy for treating CRC. The illustration depicts the relationship between interleukins and their receptors as a driver of CRC development and the potential therapeutic targets.

Integrated analysis of single-cell RNA-seq and bulk RNA-seq unravels T cell-related prognostic risk model and tumor immune microenvironment modulation in triple-negative breast cancer

Triple negative breast cancer (TNBC) is an aggressive and fatal malignancy. The current success of tumor immunotherapy has focused attention on intermediate T-cell subsets and the tumor microenvironment, which are essential for activation of the anti-tumor response. Therefore, both areas require further research to accelerate progress in developing tailored immunotherapeutic approaches for patients with TNBC. We obtained scRNA-seq data of TNBC from the GEO database. A multiplex strategy was used to analyze and identify the T-cell heterogeneity of TNBC. By combining the METABRIC and GEO databases, a prognostic risk model for T-cell marker genes was constructed and validated. In addition, the immune-infiltrating cells of TNBC was analyzed using CIBERSORT, and the association between the risk model and response to immunotherapy was investigated. Based on scRNA-seq data, 25,932cells were identified for multiple analyzes. T cells were studied with a focus on 2 subtypes, including CD8+ and CD4+. There were also communication relationships between T cells and multiple cell types. The results of the enrichment analysis showed that the T-cell marker genes were focused in pathways related to the immune system. In addition, OPTN, TMEM176A, PKM and HES1 deserve attention as prognostic markers in TNBC. The immune infiltration results showed that the high-risk group had significant immune cell infiltration and immunosuppression status. This study provides a resource for understanding T-cell heterogeneity and the associated prognostic risk model for TNBC. The results show that the model helps predict prognosis and response to treatment in breast cancer.

Abstract 1478: Broad downregulation of normal-specific super-enhancer associated genes in lung adenocarcinoma

Abstract Background Lung adenocarcinoma (LUAD) is the most common histologic subtype of lung cancer and a highly heterogeneous disease whose mechanism is not fully uncovered. Recently, Super-enhancers (SEs), tissue-specific clusters of enhancer elements, were found to drive cell identity genes and play an important role in tumorigenesis. However, current studies focus on SE in lung tumors but largely neglect those specific in normal lung tissues, which also provide critical data for understanding transformation of normal cells into cancer cells. For the first time, this study characterized normal-specific SE-associated genes (SEGs) in LUAD by dysregulation in tumor, prognostic significance and tumor microenvironment (TME) interactions via a comprehensive analysis of 22 bulk and single-cell transcriptomic datasets. Methods We analyzed TCGA datasets of 10 cancer types, and additional datasets comprising 4 datasets of LUAD tumor and normal paired samples, 5 datasets of LUAD tumors with survival information, and 3 single-cell transcriptomic datasets. For each dataset, standard methods were used for data preprocessing and normalization according to its generation platforms (e.g., microarray, bulk RNA-seq and scRNA-seq). For downstream analyses, paired t-test and linear model were used to identify dysregulated SEGs; Cox Proportional Hazards Regression was used to evaluate their prognostic significance and LASSO was used to select features for building multivariate prognostic models; bulk data deconvolution and correlation analysis were applied to assess the association of TME cell composition and SEG expression; Gene set enrichment analysis was applied for functional analysis. Results We found normal-lung SEGs were significantly disproportionally downregulated in LUAD tumors (Chi-squared test, p < 0.01), and associated with poor prognosis of patients. The patterns were consistently found in discovery (TCGA) and independent validation datasets. Interestingly, the effect appears specific to lung as such downregulation of normal-lung SEGs was also found in lung squamous cell carcinoma but not observed in most of other 8 cancer types. The downregulated SEGs were significantly involved in cell differentiation, apoptosis, proliferation, and stem cell pluripotency, and were enriched in tumor suppressors. Also, their downregulation correlate with reduced endothelial cells and lower immune activity with reduced B and CD8 T cells and inhibited immune target genes. Conclusions Our study characterized the genes associated to normal-specific SEs in LUAD, shedding sheds light on their role in tumorigenesis of lung cancers. Their broad downregulation indicates a significant effect of SE aberrancy in the transformation of normal cell into cancer cells with a modulation of immune microenvironment; further functional studies are needed to elucidate the underlying mechanism. Citation Format: Guoshuai Cai, Yihan Liu, Xiang Cui, Christopher Amos, Feifei Xiao. Broad downregulation of normal-specific super-enhancer associated genes in lung adenocarcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 1478.

MUC1 Expression Affects the Immunoflogosis in Renal Cell Carcinoma Microenvironment through Complement System Activation and Immune Infiltrate Modulation

Mucin1 (MUC1), a glycoprotein associated with an aggressive cancer phenotype and chemoresistance, is aberrantly overexpressed in a subset of clear cell renal cell carcinoma (ccRCC). Recent studies suggest that MUC1 plays a role in modulating cancer cell metabolism, but its role in regulating immunoflogosis in the tumor microenvironment remains poorly understood. In a previous study, we showed that pentraxin-3 (PTX3) can affect the immunoflogosis in the ccRCC microenvironment by activating the classical pathway of the complement system (C1q) and releasing proangiogenic factors (C3a, C5a). In this scenario, we evaluated the PTX3 expression and analyzed the potential role of complement system activation on tumor site and immune microenvironment modulation, stratifying samples in tumors with high (MUC1H) versus tumors with low MUC1 expression (MUC1L). We found that PTX3 tissue expression was significantly higher in MUC1H ccRCC. In addition, C1q deposition and the expressions of CD59, C3aR, and C5aR were extensively present in MUC1H ccRCC tissue samples and colocalized with PTX3. Finally, MUC1 expression was associated with an increased number of infiltrating mast cells, M2-macrophage, and IDO1+ cells, and a reduced number of CD8+ T cells. Taken together, our results suggest that expression of MUC1 can modulate the immunoflogosis in the ccRCC microenvironment by activating the classical pathway of the complement system and regulating the immune infiltrate, promoting an immune-silent microenvironment.

Comprehensive Analysis Identified Glycosyltransferase Signature to Predict Glioma Prognosis and TAM Phenotype.

Glycosylation is the most common posttranslational modification of proteins. Glycosyltransferase gene differential expression dictates the glycosylation model and is epigenetically regulating glioma progression and immunity. This study is aimed at identifying the glycosyltransferase gene signature to predict the prognosis and immune characteristics of glioma. The glycosyltransferase gene signature of glioma was identified in the TCGA database and validated in the CGGA database. Glioma patients were then divided into high- and low-risk groups based on risk scores to compare survival differences and predictive capacity. Subsequently, validation of glycosyltransferase gene signature merits by comparing with other signatures and utility in clinical judgment. The immune cell infiltration, immune pathways, and immune checkpoint expression level were also analyzed and compared in the high- and low-risk groups. Finally, the signature and its gene function were tested in our cohort and in vitro experiments. Eight glycosyltransferase genes were identified to establish the glycosyltransferase signature to predict the prognosis of glioma patients. The survival time was shorter in the high-risk group compared to the low-risk group based on glycosyltransferase signature and was confirmed in an independent external cohort. The glycosyltransferase signature displayed outstanding predictive capacity than other signatures in the TCGA and CGGA database cohorts. Furthermore, patients in the high-risk group were positively correlated with TAM infiltration, immune checkpoint expression level, and protumor immune pathways in TCGA cohorts. Validation of clinical tissue specimens revealed that the high-risk group was closely associated with infiltration of M2 TAMs. High-risk genes in the signature promote glioma proliferation, invasion, and macrophage recruitment in an in vitro validation of U87 and U251 cell lines. This carefully constructed that glycosyltransferase signature can predict the prognosis and immune profile of gliomas and help us evaluate subsequent macrophage-targeted therapies as well as other immune microenvironment modulation therapeutic strategies.

Novel cellular senescence-related risk model identified as the prognostic biomarkers for lung squamous cell carcinoma.

Lung cancer is one of the top causes of cancer-related death worldwide. Cellular senescence is a characteristic of cell cycle arrest that plays a role in carcinogenesis and immune microenvironment modulation. Despite this, the clinical and immune cell infiltration features of senescence in lung squamous cell carcinoma (LUSC) are unknown. The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) were used to get RNA-seq data and clinical information for LUSC. The least absolute shrinkage and selection operator (LASSO)-Cox regression, receiver operating characteristic (ROC), and Kaplan-Meier analysis were used to evaluate a risk model for predicting overall survival based on six differentially expressed genes. The tumor microenvironment (TME) and immunotherapy response were also studied. To discriminate LUSC into high- and low-risk subgroups, a risk model comprised of six cellular senescence-related genes (CDKN1A, CEBPB, MDH1, SIX1, SNAI1, and SOX5) was developed. The model could stratify patients into high-risk and low-risk groups, according to ROC and Kaplan-Meier analysis. In the TCGA-LUSC and GSE73403 cohorts, the high-risk group had a worse prognosis (P<0.05), and was associated with immune cell inactivation and being insensitive to immunotherapy in IMvigor210. We discovered a new LUSC classification based on six cellular senescence-related genes, which will aid in identifying patients who will benefit from anti-PD-1 treatment. Targeting senescence-related genes appears to be another option for improving clinical therapy for LUSC.

FLASH Modulation of Immune Microenvironment in Diffuse Midline Glioma (DMG) at Single-Cell Resolution

<h3>Purpose/Objective(s)</h3> Diffuse Midline Glioma with H3K27M mutation (DMG) is a universally fatal tumor primarily treated with radiotherapy (RT) and typically unresponsive to immune-based therapies. FLASH is a novel RT technique associated with decreased toxicity and effective tumor control in glioma models as well as immune-sparing properties in other cancer models. However, the effect of FLASH on the DMG tumor immune microenvironment (TIME) has not yet been explored. <h3>Materials/Methods</h3> Using a syngeneic murine brainstem DMG, we performed single-cell RNA sequencing on CD45+ cells isolated from tumors 4 days after posterior fossa irradiation (15Gy x 1, 9MeV), utilizing either ultra-high dose rate (90Gy/sec, FLASH) or conventional (2Gy/min, CONV) RT, and compared to unirradiated tumor (SHAM). For differential gene expression analysis, we compared CONV to SHAM (CvS) and FLASH to SHAM (FvS). We also performed single cell gene set enrichment scores (ssGSEA) for evaluation of immune signatures from gene ontology (GO); ssGSEA scores were deemed significant by a p<0.05 using Mann-Whitney U test. We validated our most robust immune markers with dual immunofluorescence. <h3>Results</h3> Unsupervised clustering of 23,165 CD45+ cells revealed 16 immune clusters, including subtypes of resident microglia (MG, 78.2% of total cells), lymphocytes (6.4%), macrophages (MPs, 5.2%), monocytes (1.8%), and dendritic cells (DCs, 1.7%). MG consisted of four distinct subtypes representing a spectrum of homeostatic to activated cellular states. In the most activated MG subtype, both CONV and FLASH showed an upregulation of interferon (IFN) genes such as Isg15 (Fold Change (FC) 1.03 CvS, 0.94 FvS) and Ifit3 (FC 0.77 CvS, 0.66 FvS) when compared to SHAM. Furthermore, ssGSEA of MG found IFN scores increased in both FvS (p < 0.0001) and CvS (p < 0.0001) while TGFbR signaling score was increased in FvS (p < 0.0001) and decreased in CvS (p < 0.0001). In non-resident myeloid clusters, the most differential response was found in MPs and DCs with robust upregulation of IFN genes for CvS (Isg15 FC 2.30 MPs, 2.67 DCs; Ifit3 FC 2.02 MPs, 2.06 DCs), while this response was not seen with FvS. This was confirmed with ssGSEA with increased IFN scores in both MPs (CvS p<0.0001, p=0.04) and DCs (CvS p<0.0001, FvS p=0.69). FLASH showed an increase in anti-inflammatory MP markers such as Mrc1, Cd163, and Maf (FC 1.40, 1.11, 1.19) and an upregulated myeloid-derived suppressor cell signature in monocytes (FvS, p < 0.0001), not seen in CvS (p = 0.09). <h3>Conclusion</h3> Our work is the first to map CONV and FLASH immune alterations with single-cell resolution in the DMG TIME. FLASH induces IFN differentially across microglia and non-resident myeloid subsets. Further exploration is warranted to understand how FLASH impacts tumor growth through differential cytokine signaling, inflammatory responses and immune checkpoint expression within the DMG TIME.

CXCL8 Up-Regulated LSECtin through AKT Signal and Correlates with the Immune Microenvironment Modulation in Colon Cancer.

The role of CXCL8 and LSECtin in colon cancer liver metastasis and immune checkpoint inhibitors (ICIs) treatment effect were widely recognized. However, the regulatory role of CXCL8 on LSECtin is still unclear. The expression of CXCL8 or LSECtin was analyzed by TCGA database, and verified by GES110225 and clinical samples. The relationship between the expression of CXCL8 or LSECtin and immune cells infiltration, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway, Gene Ontology (GO) items, stromal score, Estimation of STromal and Immune cells in MAlignant Tumours (ESTIMAT) immune score, tumor mutation burden (TMB), mismatch repair gene and immune checkpoints expression were analyzed by Spearman. The effects of CXCL8 on LSECtin expression, proliferation, and invasion ability were clarified by recombinant CXCL8 or CXCL8 interfering RNA. In colon cancer, the expression of CXCL8 was higher, but LSECtin was lower than that in normal mucosa. The expression of CXCL8 or LSECtin was significantly positively correlated with immune cells infiltration, stromal score, ESTIMATE immune score, TMB, and immune checkpoints expression. The expression of LSECtin was closely related to the cytokine-cytokine receptor interaction pathway and response of chemokine function, such as CXCL8/CXCR1/2 pathway. There was a significant positive correlation between the expression of CXCL8 and LSECtin in colon cancer. CXCL8 up-regulated LSECtin through AKT signal and promoted the proliferation and invasion ability of colon cancer. CXCL8 up-regulated LSECtin by activating AKT signal and correlated with the immune microenvironment modulation in colon cancer.

A self-assembled bilayer polypeptide-engineered hydrogel for spatiotemporal modulation of bactericidal and anti-inflammation process in osteomyelitis treatment

BackgroundDrug resistance of pathogens and immunosuppression are the main causes of clinical stagnation of osteomyelitis. The ideal treatment strategy for osteomyelitis is to achieve both efficient antibacterial and bone healing through spatiotemporal modulation of immune microenvironment.MethodsIn this study, a bilayer hydrogel based on genetically engineered polypeptide AC10A and AC10ARGD was prepared by self-assembly. Ag2S QDs@DSPE-mPEG2000-Ce6/Aptamer (AD-Ce6/Apt) was loaded in the top layer AC10A hydrogel (AA) for antibacterial, and bone marrow-derived mesenchymal stem cells (BMSCs) were loaded in the lower layer AC10ARGD hydrogel (MAR) for bone healing. The AD-Ce6/Apt can be released from the AA hydrogel to target S. aureus before bacterial biofilm formation and achieved significant bactericidal effect under irradiation with a 660 nm laser. Moreover, AD-Ce6/Apt can induce M1 type polarization of macrophages to activate the immune system and eliminate residual bacteria. Subsequently, BMSCs released from the MAR hydrogel can differentiate into osteoblasts and promote the formation of an anti-inflammatory microenvironment by regulating the M2 type polarization of macrophages. The bilayer AA-MAR hydrogel possessed good biocompatibility.ResultsThe in vitro and in vivo results showed that the AA-MAR hydrogel not only realized efficient photodynamic therapy of S. aureus infection, but also promoted the transformation of immune microenvironment to fulfill the different needs of each stage, which ultimately improved bone regeneration and mechanical properties post-surgery.ConclusionThis work presents an approach for spatiotemporal modulation of immune microenvironment in the treatment of osteomyelitis.Graphical

OS08.4.A Analysis of melanoma brain metastasis immune microenvironment through multiplex gene expression profiling

Abstract Background Novel immunotherapies based on targeting of specific immune checkpoints enabled a significant improvement of melanoma outcome, but melanoma brain metastases (BM) remain an unmet oncological need with an overall 2-year survival rate lower than 10%. Tumour immune microenvironment has been demonstrated to play a key role in BM establishment and development, but data regarding the specific milieu of melanoma BM is limited. Material and Methods Gene expression profiles of 55 samples of primary melanoma and BM were evaluated using the nCounter PanCancer IO 360 Panel (NanoString Technologies) targeting 770 mRNA involved in tumor immune microenvironment modulation. The case series consisted of 10 primary melanomas and their 10 matched BM, 25 unmatched BM, and 10 locally advanced control melanomas without evidence of BM after &amp;gt;5 year follow up. Results Among BM samples, most patients (25/45) were males and median age at BM diagnosis was 61,2 years with a median time to BM development of 2,1 years. Median OS from BM diagnosis was 1,3 years. Several genes resulted significantly downregulated in BM compared to primary melanomas, including SERPINB5 (p&amp;lt;0.001), ARG1 (p=0.0067), S100A8 (p&amp;lt;0.001), S100A9 (p&amp;lt;0.001), S100A12 (p=0.0037), IL1RN (p=0.0012), CCL21 (p=0.0012), CCL22 (p=0.0012) and CCL13 (p=0.037) and SELE (p=0.026); conversely, C7 was upregulated (p&amp;lt;0.001). Downregulated signatures in BM involved those associated with multiple immune cell populations, including neutrophils, dendritic cells, mast cells and Treg, as well as inflammatory chemokines, the CTLA4 immune checkpoint and ARG1 enzyme function; conversely, MAGEs-related signature was upregulated. Comparison between primary melanomas which developed BM and those which did not showed a significant overexpression of RRM2 (p=0.0247) and TNFRSF1A (p=0.032) genes in the latter group and an upregulation of the PD-1 pathway. Analysis according to tumour mutational status showed an upregulation of signatures associated with inflammatory chemokines, dendritic and myeloid cells and neutrophils. No differences were observed according to time to BM development and survival from BM diagnosis. Conclusion Our findings show that melanoma BM harbor distinct immunosuppressive mechanisms compared to primary tumors: this data elicits the importance of investigating the heterogeneity of BM microenvironment. Genes and pathways selectively overexpressed or downregulated in melanoma BM should be validated to be possibly considered as novel therapeutic targets.

Tumor immune microenvironment modulation by cholesterol in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is considered one of the most aggressive tumors worldwide. The consumption of lipid-enriched diets, mainly high cholesterol, induces oxidative stress and chronic inflammation, leading to HCC progression. Moreover, fatty acids and cholesterol could display differential responses on immune cells inside the tumor immune microenvironment (TIME). Tumor-associated macrophages (TAMs) represent one of the most critical leukocytes in the tumor microenvironment (TME) displaying pro-tumoral responses and one of the mainly cholesterol donors to cancer cells. Immunotherapy or cholesterol regulators, alone or combined, would represent an effective strategy for HCC treatment. Nonetheless, steatotic etiology from non-alcoholic fatty liver disease (NAFLD)-HCC tumors has been unexpectedly resulting in highly aggressive behavior.

Construction and Validation of an Epigenetic Regulator Signature as A Novel Biomarker For Prognosis, Immunotherapy, And Chemotherapy In Hepatocellular Carcinoma.

BackgroundEpigenetic modification regulates various aspects of cancer biology, from tumor growth and invasion to immune microenvironment modulation. Whether epigenetic regulators (EGRs) can decide tumor malignant degree and risk of immune evasion in liver hepatocellular carcinoma (LIHC) remains unclear.MethodAn EGR signature called “EGRscore” was constructed based on bulk RNA-seq data of EGR in hepatocellular carcinoma (HCC). The correlation between EGRscore and overall survival (OS) was validated in HCC cohorts and other tumor cohorts. Mutation profiles, copy number alterations (CNAs), enriched pathways, and response to immunotherapy and chemotherapy were compared between EGRscore-high and EGRscore-low patients.ResultsWe found that EGRscore was associated with OS in HCC as well as several tumors including glioma, uveal melanoma (UVM), and kidney tumors. A mechanism study demonstrated that the distinct mutation profile of TP53 was present in EGRscore-high and EGRscore-low patients. Meanwhile, EGRscore-low patients were characterized with immune cells that promote killing tumors. Furthermore, EGRscore was associated with genes regulating drug resistance in HCC. Finally, we indicated that EGRscore-low patients had higher response rates to immunotherapy and targeted therapy.ConclusionsEGRscore could be used to distinguish OS, tumor progression, mutation pattern, and immune microenvironment. The present study contributes to improving hepatocellular carcinoma patient prognosis and predicting response to immunotherapy.

Oral antimicrobial peptide-EGCG nanomedicines for synergistic treatment of ulcerative colitis.

The pathogenesis of ulcerative colitis (UC) is associated with severe inflammation, damaged colonic barriers, increased oxidative stress, and intestinal dysbiosis. The majority of current medications strive to alleviate inflammation but fail to target additional disease pathologies. Addressing multiple symptoms using a single 'magic bullet' remains a challenge. To overcome this, a smart epigallocatechin-3-gallate (EGCG)-loaded silk fibroin-based nanoparticle (NP) with the surface functionalization of antimicrobial peptides (Cathelicidin-BF, CBF) was constructed, which could be internalized by Colon-26 cells and RAW 264.7 macrophages with high efficiencies. The resulting CBF-EGCG-NPs efficiently restored colonic epithelial barriers by relieving oxidative stress and promoting epithelium migration. They also alleviated immune responses through downregulation of pro-inflammatory factors, upregulation of anti-inflammatory factors, M2 macrophage polarization, and lipopolysaccharide (LPS) elimination. Interestingly, oral administration of hydrogel (chitosan/alginate)-embedding CBF-EGCG-NPs could not only retard progression and treat UC, but also modulate intestinal microbiota by increasing their overall diversity and richness and augmenting the abundance of beneficial bacteria (e.g., Firmicutes and Lactobacillaceae). Our work provides a "many birds with one stone" strategy for addressing UC symptoms using a single NP-based oral platform that targets immune microenvironment modulation, LPS clearance, and microbial remodeling.

Intratumoral injection of TLR9 agonist promotes an immunopermissive microenvironment transition and causes cooperative antitumor activity in combination with anti-PD1 in pancreatic cancer

BackgroundComplex tumor and immune microenvironment render pancreatic ductal adenocarcinoma (PDAC) resistant to immune checkpoint inhibitors (ICIs). Therefore, a strategy to convert the immune hostile into an immunopermissive tumor is required....

Abstract LB061: On-target peripheral and tumor immune microenvironment modulation in patients treated with lacnotuzumab (anti-CSF1, MCS110) + spartalizumab

Abstract Background: The CSF-1/CSF-1R (colony-stimulating factor-1) pathway plays a significant role in the tumor microenvironment via regulation of tumor-associated macrophages (TAMs). Lacnotuzumab (MCS110) is a humanized monoclonal antibody against CSF-1. Lacnotuzumab may counteract the tumor suppressive microenvironment induced by CSF-1, potentially enhancing the efficacy of PD-1 inhibition. Methods: MCS110Z2102 is a phase 1b/2 study in cancer patients with advanced malignancies treated by lacnotuzumab combined with the PD-1 inhibitor spartalizumab. Eligible patients with previously treated advanced/metastatic solid tumors received 1, 3, 5, 7.5 and 10 mg/kg intravenous doses of lacnotuzumab in dose escalation combined with 100 mg or 300 mg of spartalizumab administered every 3 weeks. Then, the selected recommended phase 2 dose (RP2D, 7.5 mg/kg lacnotuzumab in combination with 300 mg spartalizumab every 3 weeks) was explored in 4 expansion groups of pancreatic cancer, triple-negative breast cancer (TNBC), endometrial cancer (EC) and malignant melanoma. Here, we report flow cytometric, circulating total CSF1 in plasma and gene expression profiling analyses as evidence of on-target pharmacodynamic effects of lacnotuzumab + spartalizumab in treated patients. Results: The combination of lacnotuzumab and spartalizumab increased the levels of circulating total CSF-1 in plasma, thereby suggesting target engagement and selectively decreased peripheral CSF-1R-expressing intermediate and nonclassical monocytes, at all doses tested. Gene expression profiling by RNA-sequencing in paired biopsies showed down-regulation of macrophage associated genes in patients treated with lacnotuzumab + spartalizumab. In addition, the upregulation of cytotoxic T cell gene signatures was observed. A limited antitumor activity was observed: 2 pancreatic cancer, 1 TNBC and 2 EC patients had a confirmed partial response over 141 patients treated. Conclusions: Flow cytometric, circulating total CSF1 in plasma and gene expression profiling results demonstrated that targeting CSF-1 with lacnotuzumab in the periphery and tumor microenvironment leads to decrease in monocytes and reduced expression of macrophage associated genes in patients with advanced cancers. Unfortunately, in the heavily pretreated patient populations studied in this trial, only a limited clinical efficacy was demonstrated. Citation Format: Jincheng Wu, Shuqi Chen, Guillaume Baneyx, Anne-Laure Marchal, David S. Quinn, Miguel Martin, Andres Cervantes, Janna Sand-Dejmek, Jennifer Marie Mataraza. On-target peripheral and tumor immune microenvironment modulation in patients treated with lacnotuzumab (anti-CSF1, MCS110) + spartalizumab [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr LB061.

Gene fusion neoantigens: Emerging targets for cancer immunotherapy.

Tumor neoantigens play an important role in current cancer immunotherapies. The most commonly studied class of tumor neoantigens contains those derived from single-nucleotide variants (SNVs) and insertions or deletions (Indels). However, gene fusions are also ideal sources of tumor neoantigens, as they can form new open reading frames (ORFs). Compared with SNV and Indel (SNV&Indel) neoantigens, fusion gene neoantigens tend to be more immunogenic, have more targets per mutation, and are more broadly shared across different cancer types. As a result, they are an important class of tumor neoantigens and emerging targets for cancer immunotherapies, with uses as prognostic biomarkers of immune checkpoint blockade (ICB) and in the development of tumor vaccines, adoptive cell therapies and tumor immune microenvironment modulation. In this review, we introduce the chromosomal basis and characteristics of gene fusions. Then, we summarize the predictive tools, mutation burden and immunogenicity of gene fusion neoantigens. Further, we discuss applications and future improvements of gene fusion neoantigens with respect to current cancer immunotherapies and novel developments in cancer treatment.

Adipose Extracellular Vesicles in Intercellular and Inter-Organ Crosstalk in Metabolic Health and Diseases.

Adipose tissue (AT) is a highly heterogeneous and dynamic organ that plays important roles in regulating energy metabolism and insulin sensitivity. In addition to its classical roles in nutrient sensing and energy storage/dissipation, AT secretes a large number of bioactive molecules (termed adipokines) participating in immune responses and metabolic regulation through their paracrine and/or endocrine actions. Adipose-derived extracellular vesicles (ADEVs), including exosomes, microvesicles (MVs), and apoptotic bodies, have recently emerged as a novel class of signal messengers, mediating intercellular communications and inter-organ crosstalk. In AT, ADEVs derived from adipocytes, immune cells, mesenchymal stem cells, endothelial cells are actively involved in modulation of immune microenvironment, adipogenesis, browing of white adipose tissue, adipokine release and tissue remodeling. Furthermore, ADEVs exert their metabolic actions in distal organs (such as liver, skeletal muscle, pancreas and brain) by sending genetic information (mainly in the form of microRNAs) to their target cells for regulation of gene expression. Here, we provide an updated summary on the nature and composition of ADEVs, and their pathophysiological functions in regulating immune responses, whole-body insulin sensitivity and metabolism. Furthermore, we highlight the latest clinical evidence supporting aberrant production and/or function of ADEVs as a contributor to obesity-related chronic inflammation and metabolic complications and discuss the opportunities and challenges in developing novel therapies by targeting ADEVs.

Single-cell RNA-seq Reveals Chemoradiotherapy-induced Immune Microenvironment Modulation in Locally Advanced Cervical Cancer

Single-cell RNA sequencing (scRNA-seq) could reshape cancer research by allowing comprehensive analysis of cellular heterogeneity and cell-type classification. We sought to investigate the immune microenvironment modulation induced by concurrent chemoradiotherapy (CCRT) in locally advanced cervical cancer at single-cell resolution. Using scRNA-seq and bioinformatics, we analyzed 3,674 and 6,541 CD45+ tumor-infiltrating immune cells from 3 pairs of tumor biopsies before and at the middle of CCRT in locally advanced cervical cancer patients. Immune cells were sorted by flow cytometry and sequenced by 10X genomics at single-cell resolution. Immunostaining and bulk sequencing dataset were used to validate our findings of scRNA-seq. A total of 14 clusters of tumor-infiltrating immune cells were observed in cervical cancer, including 6 subsets of macrophages, 2 subsets of natural killer (NK) cells, CD8+ T cells, regulatory T cells, proliferated T cells, B cells, dendritic cells, plasma cells. We found 2 transitional macrophages subsets between 2 subsets of M1 and 2 subsets of M2 macrophages in tumors. CCRT for cervical cancer induced the transition of macrophages from M2 to transitional-like to M1 macrophages. Interestingly, 2 subsets of M1 macrophages were predominant in tumors during CCRT, but not before CCRT. Additionally, most of NK cells undergoing exhaustion in pre-CCRT samples, while another cluster of NK cells with cytotoxic and activated phenotype were prevalent in tumors during CCRT. Our study reveals the anti-tumor immune response activated by CCRT at single-cell resolution in locally advanced cervical cancer, which may help further understand the mechanism of anti-tumor effect of CCRT and optimize treatment strategies.

Abstract CT172: Pharmacodynamic and gene expression profiling of patients treated with BLZ945 + spartalizumab demonstrates on-target peripheral and tumor immune microenvironment modulation

Abstract Background: The colony stimulating factor 1 receptor (CSF-1R) signaling pathway promotes tumor progression via the recruitment, differentiation, and survival of immuno-suppressive tumor-associated macrophages (TAMs). Blocking CSF-1R signaling may lead to the depletion of TAMs and increased T-cell activation. BLZ945 is an oral, highly selective and potent kinase inhibitor of CSF-1R, which can cross the blood-brain barrier. By reducing TAMs and promoting a pro-inflammatory microenvironment, BLZ945 may stimulate T-cell responses, thereby sensitizing solid tumors to anti–PD-1 therapy. Methods: BLZ945X2101 is an ongoing Ph I/II study investigating the use of BLZ945 as single agent and in combination with spartalizumab (anti–PD-1) in advanced solid tumors. Eligible pts (aged ≥18 years, ECOG 0–1) with advanced/metastatic solid tumors received BLZ945 (300 mg–1600 mg QD and 600 mg BID) Q1W, 7d on/7d off (150 mg–300 mg QD), or 4d on/10d off (300 mg–1200 mg QD and 600 mg BID); or BLZ945 (150 mg–1400 mg QD, 600 mg–800 mg BID) Q1W or 4d on/10d off (300 mg–1200 mg) plus spartalizumab at a fixed dose of 400 mg IV, Q4W. Baseline and on-treatment tumor samples were collected. Here we report flow cytometric, soluble ligand and gene expression profiling analyses as evidence of on-target pharmacodynamic effects of BLZ945 + spartalizumab in treated patients. Results: In total, paired samples for 61 pts for flow cytometry, samples from 30 pts for CSF-1 plasma and paired samples from 35 pts for RNAseq analysis were analyzed. BLZ945 (+/-spartalizumab) induced increases in plasma CSF-1 and decreased peripheral intermediate and nonclassical monocytes, at all doses and schedules tested. Gene expression profiling by RNAseq in paired biopsies showed downregulation of macrophage associated genes in patients treated with both single-agent BLZ945 and BLZ945 + spartalizumab. In patients treated with the BLZ945 + spartalizumab combination, upregulation of cytokine, chemokine, and HLA genes was observed. Signs of antitumor activity were observed in several tumor types including glioblastoma and head and neck cancer. Conclusions: Flow cytometric, soluble ligand and gene expression profiling demonstrated BLZ945-mediated CSF-1R blockade in the periphery and tumor microenvironment in patients with advanced cancers. Ongoing analyses include identification of transcriptomic signatures associated with response. These data support further clinical development of BLZ945 ± spartalizumab in advanced cancers (NCT02829723). Citation Format: Jincheng Wu, Chia-Chi Lin, Marta Gil-Martin, Aung Naing, Liqiong Fan, Fang Yang, David Quinn, Pei-Jung Tu, Cornelia Quadt, Jennifer Mataraza. Pharmacodynamic and gene expression profiling of patients treated with BLZ945 + spartalizumab demonstrates on-target peripheral and tumor immune microenvironment modulation [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr CT172.