Density Of Immune Cells Research Articles

GPER1 signaling restricts macrophage proliferation and accumulation in human hepatocellular carcinoma

BackgroundSex hormones and their related receptors have been reported to impact the development and progression of tumors. However, their influence on the composition and function of the tumor microenvironment is not well understood. We aimed to investigate the influence of sex disparities on the proliferation and accumulation of macrophages, one of the major components of the tumor microenvironment, in hepatocellular carcinoma (HCC).MethodsImmunohistochemistry was applied to assess the density of immune cells in HCC tissues. The role of sex hormone related signaling in macrophage proliferation was determined by immunofluorescence and flow cytometry. The underlying regulatory mechanisms were examined with both in vitro experiments and murine HCC models.ResultsWe found higher levels of macrophage proliferation and density in tumor tissues from male patients compared to females. The expression of G protein–coupled estrogen receptor 1 (GPER1), a non-classical estrogen receptor, was significantly decreased in proliferating macrophages, and was inversely correlated with macrophage proliferation in HCC tumors. Activation of GPER1 signaling with a selective agonist G-1 suppressed macrophage proliferation by downregulating the MEK/ERK pathway. Additionally, G-1 treatment reduced PD-L1 expression on macrophages and delayed tumor growth in mice. Moreover, patients with a higher percentage of GPER1+ macrophages exhibited longer overall survival and recurrence-free survival compared to those with a lower level.ConclusionsThese findings reveal a novel role of GPER1 signaling in regulating macrophage proliferation and function in HCC tumors and may offer a potential strategy for designing therapies based on understanding sex-related disparities of patients.

Multi-platform biomarkers of response to an immune checkpoint inhibitor in the neoadjuvant I-SPY 2 trial for early-stage breast cancer.

Only a subset of patients with breast cancer responds to immune checkpoint blockade (ICB). To better understand the underlying mechanisms, we analyze pretreatment biopsies from patients in the I-SPY 2 trial who receive neoadjuvant ICB using multiple platforms to profile the tumor microenvironment. A variety of immune cell populations and markers of immune/cytokine signaling associate with pathologic complete response (pCR). Interestingly, these differ by breast cancer receptor subtype. Measures of the spatial distributions of immune cells within the tumor microenvironment, in particular colocalization or close spatial proximity of PD-1+ Tcells with PD-L1+ cells (immune and tumor cells), are significantly associated with response in the overall cohort as well as the in the triple negative (TN) and HR+HER2- subtypes. Our findings indicate that biomarkers associated with immune cell signaling, immune cell densities, and spatial metrics are predictive of neoadjuvant ICB efficacy in breast cancer.

CD248 cleaved form in human colorectal cancer stroma: implications for tumor behavior and prognosis.

CD248 (Endosialin/TEM-1) is upregulated in cancer, including colorectal cancer (CRC), but its exact role in tumor progression remains to be elucidated. Previous studies have shown that the extracellular domain of CD248 mediates the interaction between tumor cells and extracellular matrix proteins and that interfering with this interaction may reduce tumor invasion and migration activities. We have examined the expression of CD248 in 117 human CRC samples by immunohistochemistry and investigated the association with various clinicopathological features, including the occurrence of metastasis intra-tumoral immune cell density, and overall survival. Out of the 117 specimens analyzed, 76.1% (89/117) exhibited CD248-high stromal expression, while 23.1% (28/117) demonstrated CD248-low stromal expression. Interestingly, we detected the presence of a cleaved form of CD248, which appears to accumulate in the stromal extracellular matrix. A higher metastasis rate (lymph node and distant) was observed in the CD248-low group (21/28, 75.0% versus 44/89, 49.4%, p=0.02). In addition, CD248-low tumors had fewer CD163-positive macrophages and FoxP3-positive regulatory T cells (p<0.05) with no significant difference in CD8-positive T-cell infiltration and PD-L1 expression between the groups (p>0.05). Finally, overall survival was lower in CD248-low tumors than in CD248-high tumors, with 5-year survival rates of 35.7% and 57.3%, respectively (p=0.01). In a multivariate analysis, the hazard ratio of CD248-low tumors versus CD248-high tumors was 1.93 (95% confidence interval: 1.09 - 3.40; p=0.02). Our findings suggest that CD248 stromal expression may influence the TME, impacting tumor behavior and prognosis, and can serve as a promising prognostic biomarker in CRC.

Inhibition of PIM kinase in tumor associated macrophages suppresses inflammasome activation and sensitizes prostate cancer to immunotherapy.

Immunotherapy has changed the treatment paradigm for many types of cancer, but immune checkpoint inhibitors (ICIs) have not shown benefit in prostate cancer (PCa). Chronic inflammation contributes to the immunosuppressive prostate tumor microenvironment (TME) and is associated with poor response to ICIs. The primary source of inflammatory cytokine production is the inflammasome. Here, we identify PIM kinases as important regulators of inflammasome activation in tumor associated macrophages (TAMs). Analysis of clinical data from a cohort of treatment naïve, hormone responsive PCa patients revealed that tumors from patients with high PIM1/2/3 display an immunosuppressive TME characterized by high inflammation (IL-1β and TNFα) and a high density of repressive immune cells, most notably TAMs. Strikingly, macrophage-specific knockout of PIM reduced tumor growth in syngeneic models of prostate cancer. Transcriptional analyses indicate that eliminating PIM from macrophages enhanced the adaptive immune response and increased cytotoxic immune cells. Combined treatment with PIM inhibitors and ICIs synergistically reduced tumor growth. Immune profiling revealed that PIM inhibitors sensitized PCa tumors to ICIs by increasing tumor suppressive TAMs and increasing the activation of cytotoxic T cells. Collectively, our data implicate macrophage PIM as a driver of inflammation that limits the potency of ICIs and provides preclinical evidence that PIM inhibitors are an effective strategy to improve the efficacy of immunotherapy in prostate cancer.

Low PD-L1 expression, MAP2K2 alterations, and enriched HPV gene signatures characterize brain metastases in head and neck squamous cell carcinoma

BackgroundBrain metastasis (BM) is a rare but severe complication of head and neck squamous cell carcinoma (HNSCC), with limited knowledge of molecular characteristics and immunogenicity.MethodsWe analyzed 61 cases of HNSCC-BM from three academic institutions (n = 24) and Foundation Medicine Inc (FMI, n = 37). A subset of cases underwent next-generation sequencing, multiple immunofluorescence, and proximity ligation sequencing. Gene enrichment analysis compared alterations in FMI BM samples (n = 37) with local samples (n = 4082).ResultsDemographics included: median age of 59 years, 75% male, 55% current/former smokers, 75% oropharyngeal primary, and 67% human papillomavirus (HPV) +. ATM (54%), KMT2A (54%), PTEN (46%), RB1 (46%), and TP53 (46%) were frequently altered in BM samples from academic centers (62% HPV/p16+). Structural rearrangements ranged from 9 to 90 variants by proximity ligation sequencing. BMs had low densities of CD8+, PD-1+, PD-L1+, and FOXP3 + cells, and 92% had PD-L1 combined positive scores < 1%. CDKN2A (40.5%), TP53 (37.8%), and PIK3CA (27.0%) alterations were common in the FMI BMs (51% HPV+). MAP2K2 alterations and HPV + signature were enriched in FMI BMs compared to local tumors (11.8% vs. 6.4%, P = 0.005 and 51.25% vs. 26.11%, P = 0.001 respectively), and pathogenic TSC1 inactivating mutations were enriched in local tumors (67.3% vs. 37.8%, P = 0.008). Median overall survival from BM diagnosis was 9 months (range 0–27).ConclusionsHNSCC patients with BM frequently have oropharyngeal primary sites and are HPV+. Common molecular alterations in BM samples, including targetable PIK3CA and ATM, were identified. MAP2K2 alterations were enriched and densities of immune cells were low, highlighting potential targets for further research and immunotherapy considerations.

Cancer cell-extrinsic STING shapes immune-active microenvironment and predicts clinical outcome in gastric cancer.

The activation of cGAS-STING pathway can be triggered by cytosolic double-stranded DNA (dsDNA) in tumor and non-tumor compartments. We aim to assess the constitutive expression of dsDNA-cGAS-STING axis in different cellular contexts and compare their relative contribution to clinical outcomes. A cohort of 154 cases of patients with newly diagnosed gastric cancer were enrolled in this study to evaluate the histo-score of cytosolic dsDNA, cGAS, and STING via immunohistochemistry as well as the types and densities of tumor-infiltrating immune cells. Kaplan-Meier method, multivariable regression, and receiver operating characteristic curve were implemented to analyze the prognostic efficacy of dsDNA-cGAS-STING axis in distinct compartments. The supra-normal concentration of cytosolic dsDNA correlated with the constitutive expression of cGAS-STING pathway in tumor compartments. In contrast to the lack of STING within cancer cells, the higher STING expression in non-tumor compartments indicated a transcellular cGAS-STING activation. Cancer cell-extrinsic STING was supported to potentiate nucleic acid immunity by sensing tumor-derived dsDNA fragments. Compartmental analyses also confirmed that the level of STING expressed in non-tumor cells was associated with the infiltration of protective immune cells, leading to the prolonged overall survival. Multivariate analysis further identified the independent prognostic value of cancer cell-extrinsic STING and its predictive accuracy could be significantly improved in combination with the immune cell infiltration. Cancer cell-extrinsic STING facilitates the remodeling of immune-active tumor microenvironment and acts as an independent prognostic factor in gastric cancer.

The tumor immune microenvironment of SCLC is not associated with its molecular subtypes

IntroductionSmall-cell lung carcinoma (SCLC) is a high-grade neuroendocrine carcinoma of poor prognosis. Although immune checkpoint blockers have shown promising results in advanced SCLC, the tumor immune microenvironment (TME) remains poorly understood, with no validated prognostic or predictive biomarkers of efficacy. MethodsThis retrospective study included surgically samples from 48 SCLC patients between 2009 and 2018. We assessed the TME using two quantitative 7-plex immunofluorescence panels focusing on T and B cells, and compared it to NSCLC (N = 10). Molecular subtypes were determined by assessing the expression of ASCL1, NEUROD1 and YAP1 using immunohistochemistry. ResultsImmune-hot SCLC were defined as those exhibiting the highest immune cell and immune-related marker densities. They were associated with longer overall survival, significantly more frequently detected at early stages, and exhibited high PD-L1 expression in immune cells, but were not associated with molecular subtypes. Compared to NSCLC, SCLC had significantly lower densities of CD20 + cells and higher density of PD1 + cells, with no significant differences in CD4 + , CD8 + and plasma cell densities. In univariate analysis, the highest OS was significantly associated with early stage (p < 0.001), low expression of NEUROD1 (p = 0.047), high PD1 + cell density (p < 0.001) and high PD-L1 immune cell expression (p = 0.04). Only stage and PD1 + cell density emerged as independent prognostic markers. ConclusionSCLC TME is highly heterogeneous. Immune-hot tumors were associated with OS but not with molecular classification. PD1 expression and PD-L1 expression by immune cells may thus serve as a prognostic marker.

Myocardial inflammatory cells in cardiac amyloidosis

Background: Immunoglobulin derived AL amyloidosis and transthyretin derived ATTR amyloidosis are the most common forms of cardiac amyloidosis. Both may present with cardiac arrhythmias, heart failure, and extracardiac symptoms. Disease outcome is often fatal. Recently, it was proposed that amyloid may cause cardiac inflammation. Here we tested the hypothesis that immune cell infiltration in cardiac tissue correlates with clinicopathological patient characteristics. Patients and methods: Myocardial biopsies from 157 patients with cardiac amyloidosis (46.5% AL, 53.3% ATTR) were immunohistochemically assessed for the presence and amount of T lymphocytes (CD3), macrophages (CD68) and neutrophils (MPO). Amyloid load, cardiomyocyte diameter, apoptosis (Caspase 3), necrosis (complement 9), and various clinical parameters were assessed and correlated with immune cell density. Results: Myocardial tissue was infiltrated with T lymphocytes (CD3), macrophages (CD68) and neutrophils (MPO) with variable amounts. Significant correlations were found between the number of macrophages and NYHA class. No correlations were found between the presence and amount of T lymphocytes, neutrophils and clinicopathological patient characteristics. Conclusion: The significant correlation between cardiac macrophage density and heart failure points towards a significant role of macrophages in disease pathology.

Pulmonary epithelial wound healing and the immune system. Mathematical modelling and bifurcation analysis of a bistable system

Respiratory diseases such as asthma, acute respiratory distress syndrome (ARDS), influenza or COVID-19 often directly target the epithelium. Elevated immune levels and a ‘cytokine storm’ are directly associated with defective healing dynamics of lung diseases such as COVID-19 or ARDS. The infected cells leave wounded regions in the epithelium which must be healed for the lung to return to a healthy state and carry out its main function of gas-exchange. Due to the complexity of the various interactions between cells of the lung epithelium and surrounding tissue, it is necessary to develop models that can complement experiments to fully understand the healing dynamics. In this mathematical study we model the mechanism of epithelial regeneration. We assume that healing is exclusively driven by progenitor cell proliferation, induced by a chemical activator such as epithelial growth factor (EGF) and cytokines such as interleukin-22 (IL22). Contrary to previous studies of wound healing, we consider the immune system, specifically the T effector cells TH1, TH17, TH22 and Treg to strongly contribute to the healing process, by producing IL22 or regulating the immune response. We therefore obtain a coupled system of two ordinary differential equations for the epithelial and immune cell densities and two functions for the levels of chemicals that either induce epithelial proliferation or recruit immune cells. These functions link the two cell equations. We find that to allow the epithelium to regenerate to a healthy state, the immune system must not exceed a threshold value at the onset of the healing phase. This immune threshold is supported experimentally but was not explicitly built into our equations. Our assumptions are therefore sufficient to reproduce experimental results concerning the ratio TH17/Treg cells as a threshold to predict higher mortality rates in patients. This immune threshold can be controlled by parameters of the model, specifically the base-level growth factor concentration. This conclusion is based on a mathematical bifurcation analysis and linearization of the model equations. Our results suggest treatment of severe cases of lung injury by reducing or suppressing the immune response, in an individual patient, assessed by their disease parameters such as course of lung injury and immune response levels.

Clinical prognosticators and targets in the immune microenvironment of intrahepatic cholangiocarcinoma

ABSTRACT Background Intrahepatic cholangiocarcinoma (ICC) is a disease with poor prognosis and limited therapeutic options. We investigated the tumor immune microenvironment (TIME) to identify predictors of disease outcome and to explore targets for therapeutic modulation. Methods Liver tissue samples were collected during 2008–2019 from patients (n = 139) diagnosed with ICC who underwent curative intent surgery without neoadjuvant chemotherapy. Samples from the discovery cohort (n = 86) were immunohistochemically analyzed on tissue microarrays (TMAs) for the expression of CD68, CD3, CD4, CD8, Foxp3, PD-L1, STAT1, and p-STAT1 in tumor core and stroma areas. Results were digitally analyzed using QuPath software and correlated with clinicopathological characteristics. For validation of TIME-related biomarkers, we performed multiplex imaging mass cytometry (IMC) in a validation cohort (n = 53). Results CD68+ cells were the predominant immune cell type in the TIME of ICC. CD4+high T cell density correlated with better overall survival (OS). Prediction modeling together with validation cohort confirmed relevance of CD4+ cells, PD-L1 expression by immune cells in the stroma and N-stage on overall disease outcome. In turn, IMC analyses revealed that silent CD3+CD4+ clusters inversely impacted survival. Among annotated immune cell clusters, PD-L1 was most relevantly expressed by CD4+FoxP3+ cells. A subset of tumors with high density of immune cells (“hot” cluster) correlated with PD-L1 expression and could identify a group of candidates for immune checkpoint inhibition (ICI). Ultimately, higher levels of STAT1 expression were associated with higher lymphocyte infiltration and PD-L1 expression. Conclusions These results highlight the importance of CD4+ T cells in immune response against ICC. Secondly, a subset of tumors with “hot” TIME represents potential candidates for ICI, while stimulation of STAT1 pathway could be a potential target to turn “cold” into “hot” TIME in ICC.

CD8+ T cells infiltrating into tumors were controlled by immune status of pulmonary lymph nodes and correlated with non-small cell lung cancer (NSCLC) patients’ prognosis treated with chemoimmunotherapy

PurposeNeoadjuvant chemoimmunotherapy has the potential to reduce tumor burden, improve the pathological complete response (pCR) rate, and significantly prolong patients’ disease-free survival (DFS). However, the treatment’s effectiveness varies among NSCLC patients. The immunological mechanisms contributing to tumor regression still require further exploration and elucidation. MethodsThe immune status of patients’ local tumor microenvironment (TME) before and after neoadjuvant chemoimmunotherapy, their paired pulmonary lymph nodes (11th LNs) after therapy, including infiltrating immune cell densities and their correlations, were analyzed using multiplex immunofluorescence. ResultsFifty-six NSCLC patients undergoing neoadjuvant chemoimmunotherapy were enrolled and subsequently underwent surgical resection and pathological evaluation. Among these, 19 patients achieved a pCR, 6 patients exhibited a major pathological response (MPR), and 31 patients did not achieve MPR. There were no significant difference in the densities of CD8+ T cell, Treg and Dendritic cell (DC) in patients’ TME before neoadjuvant therapy (n = 26, P = 0.091, P = 0.753, P = 0.905, respectively), but after treament, these immune cells’ dynamics were significantly different between different response group. CD8+ T cell densities were increased in pCR gourp (P = 0.006), but not in non-pCR group (P = 0.389); the densities of Treg were increased in non-pCR gourp (P = 0.0004), but DC were significantly decreased in non-pCR gourp (P = 0.005). After surgery, the TME were also significantly different: patients achieving pCR typically demonstrated high densities of CD8+ T cell, DC and low densities of Tregs (P = 0.0001, P < 0.0001 and P = 0.0004). The immune status of 11th LNs also exhibited significant differences. DC densities were much higher in pCR patients, whereas Treg in the pCR group were significantly lower than those in the non-pCR group (P = 0.0008 and P = 0.003). Furthermore, the densities of DC in the TME showed a moderate positive correlation with DC in 11th LNs (P = 0.0002), while the densities of Tregs in the TME exhibited a moderate negative correlation with DC densities in 11th LNs (P = 0.03). Patients who had high densities of CD8+ T cell in the resection tissues and DC in the LNs, experienced longer DFS (P = 0.048 and P = 0.024). ConclusionImmune cells in both pulmonary LNs and the TME collectively influence the remodeling of the NSCLC patient’s TME, thus impacting treatment response and prognosis.

Immune Cell Densities Predict Response to Immune Checkpoint-Blockade in Head and Neck Cancer.

Pre-ICB tumor tissue sections were obtained from 9 responders (complete response, partial response, or stable disease) and 11 non-responders (progressive disease) classified via RECISTv1.1. A custom multi-immunofluorescence (mIF) staining assay was designed, optimized, and applied to characterize tumor cells (pan-cytokeratin), T cells (CD4, CD8), B cells (CD19, CD20), myeloid cells (CD16, CD56, CD163), dendritic cells (LAMP3), fibroblasts (alpha-Smooth Muscle Actin), proliferative status (Ki67) and immunoregulatory molecules (PD1). Spatial metrics were compared among groups. Serial tissue sections were scored for TLS in both H&E and mIF slides. A machine learning model was employed to measure the effect of these metrics on achieving a response to ICB (SD, PR, or CR). A higher density of B lymphocytes (CD20+) was found in responders compared to non-responders to ICB (p=0.022). A positive correlation was observed between mIF and pathologist identification of TLS (R2= 0.66, p-value= <0.0001). TLS trended toward being more prevalent in responders to ICB (p=0.0906). The presence of TLS within 100 um of the tumor was associated with improved overall (p=0.04) and progression-free survival (p=0.03). A multivariate machine learning model identified TLS density as a leading predictor of response to ICB with 80% accuracy. Immune cell densities and TLS spatial location within the tumor microenvironment play a critical role in the immune response to HNSCC and may potentially outperform CPS as a predictor of ICB response.

Integrative genomics unveils basement membrane-related diagnostic markers and therapeutic targets in esophageal squamous cell carcinoma

BackgroundEsophageal squamous cell carcinoma (ESCC) is often diagnosed at advanced stages due to the inherent limitations of current screening methodologies. Central to evaluating tumor invasion and prognostic assessment in ESCC is the integrity of the basement membrane (BM). However, current research on the implications of BM-related genes (BMRGs) in diagnosing ESCC remains sparse.MethodsWe performed a comprehensive analysis using single-cell RNA-sequencing (scRNA-seq) data from the Gene Expression Omnibus (GEO) database, alongside gene expression profiles acquired from GEO and The Cancer Genome Atlas (TCGA) databases. This identified differentially expressed BMRGs in ESCC. Employing LASSO, RF, and SVM-RFE, we selected potential BM biomarkers and crafted a diagnostic nomogram for ESCC, validated by ROC curves and AUC values. We also explored immune infiltration and biological mechanisms through consensus clustering and GSVA, and utilized single cell trajectory analysis and GSCALite to study gene distributions and pathways. In vitro experiments further elucidated the role of these genes in ESCC carcinogenesis.ResultsHere, we discovered that ESCC cell types exhibited markedly elevated BM-related scores. Our analysis pinpointed seven BM genes upregulated and linked to immune infiltration, showcasing unique gene expression profiles and varying immune cell densities across the BM-related subtypes. Furthermore, a robust positive correlation was observed between these genes expression and EMT activity. The knockdown of BGN significantly suppressed cell proliferation, migration, invasion, while also augmenting cell viability following chemotherapy drug treatment.ConclusionOur study identified seven key BMRGs (BGN, LAMB3, SPARC, MMP1, LUM, COL4A1, and NELL2) and established a diagnostic nomogram for ESCC. Of noteworthy significance is the discovery of BGN as a promising drug target, indicating a novel strategy for future clinical combination therapies in ESCC.

The Potential of Immunotherapy for SMARCA4-Deficient Undifferentiated Uterine Sarcoma (SDUS).

(1) Background: SMARCA4-deficient undifferentiated uterine sarcoma (SDUS) is a rare and aggressive cancer that urgently requires novel therapeutic strategies. Despite the proven efficacy of immunotherapy in various cancer types, its application in SDUS remains largely unexplored. This study aims to investigate the immune microenvironment of SDUS to evaluate the feasibility of utilizing immunotherapy. (2) Methods: Multiplex immunofluorescence (mIF) was employed to examine the immune microenvironment in two cases of SDUS in comparison to other subtypes of endometrial stromal sarcomas (ESSs). This research involved a comprehensive evaluation of immune cell infiltration, cellular interactions, and spatial organization within the tumor immune microenvironment (TiME). Statistical analysis was performed to assess differences in immune cell densities and interactions between SDUS and other ESSs. (3) Results: SDUS exhibited a significantly higher density of cytotoxic T lymphocytes (CTLs), T helper (Th) cells, B cells, and macrophages compared to other ESSs. Notable cellular interactions included Th-CTL and Th-B cell interactions, which were more prominent in SDUS. The spatial analysis revealed distinct immune niches characterized by lymphocyte aggregation and a vascular-rich environment, suggesting an active and engaged immune microenvironment in SDUS. (4) Conclusions: The results suggest that SDUS exhibits a highly immunogenic TiME, characterized by substantial lymphocyte infiltration and dynamic cellular interactions. These findings highlight the potential of immunotherapy as an effective treatment approach for SDUS. However, given the small number of samples evaluated, these conclusions should be drawn with caution. This study underscores the importance of additional investigation into immune-targeted therapies for this challenging cancer subtype, with a larger sample size to validate and expand upon these preliminary findings.

Effect of tumor-immune microenvironment (TIME) on disparate ascending (A) and descending (D) subtypes of nasopharyngeal carcinoma (NPC).

145 Background: Endemic NPC is invariably linked to Epstein-Barr virus infection, and often presents as locoregionally-advanced (LA-) disease. Nonetheless, it is acknowledged that LA-NPC is clinically heterogeneous, with disparate clinical presentations of ascending (A) and descending (D) subtypes that are characterized by T3-4N0-1 and T1-2N2-3 disease, respectively. Here, we investigated the TIME between these distinct NPC phenotypes using whole transcriptome sequencing and digital pathology. Methods: We utilized a cohort of 111 patients with NPC from 2 institutions – NCCS (n=68) and JXCH (n=43) as test and validation datasets, respectively. Whole transcriptome profiling using RNAseq (Illumina, CA) was performed in the NCCS cohort, while spatial analyses of hematoxylin and eosin-stained whole slide images (WSIs) were undertaken in the NCCS cohort (35 A- and 33 D-subtypes), and validated in the JXCH cohort (26 A- and 17 D-subtypes). A customized pipeline was developed to analyze the spatial relationships between tumor-rich and immune-rich regions (tiles) within the WSIs. Mean distances between each tumor-rich and its nearest immune-rich tiles were computed for each WSI. Highest and lowest quartiles of the mean distances in the test cohort were used as thresholds to classify NPC tumors into 3 immune classes of differing immune cell density. Results: Transcriptomic profiling revealed an enrichment of immune-related genesets and differentially expressed genes in D- relative to A-subtype tumors. This corresponded to observations of higher overall immune, T and B cell scores in D- than A-subtypes by deconvolution analyses (ESTIMATE and CIBERSORT). Through spatial analyses of our WSIs, we defined three immune classes – immune-dense, -sparse, and -desert, which corresponded to mean distances of &lt;88 μm, 88-208 μm, and &gt;208 μm between tumour- to immune-rich tiles, respectively. D-subtype NPC had significantly more immune-rich regions compared with A-subtypes in both NCCS and JXCH cohorts ( P=0.02 [NCCS]; P=0.01 [JXCH]). This corresponded to shorter median distances between tumor-rich to immune-rich tiles in D- than A-subtypes (103 μm vs 200 μm, P=0.01 [NCCS]; 123 μm vs250 μm, P=0.01 [JXCH]). Based on our novel spatial-based classification, we observed a higher proportion of immune dense tumors in D- than A-subtypes in the NCCS cohort, with only 3/33 (9%) D-subtypes being classified as immune desert. Using the same distance thresholds, we derived a consistent trend in the JXCH cohort, where a higher proportion of D-subtypes were classified as immune dense and sparse than A-subtypes (59% vs 31%, P=0.01). Conclusions: Our results support a model where the TIME delineates the biology underpinning the disparate clinical presentations of distinct A- and D-subtypes of LA-NPC.

Deep-learning based analysis of in-vivo confocal microscopy images of the subbasal corneal nerve plexus’ inferior whorl in patients with neuropathic corneal pain and dry eye disease

PurposeTo evaluate and compare subbasal corneal nerve parameters of the inferior whorl in patients with dry eye disease (DED), neuropathic corneal pain (NCP), and controls using a novel deep-learning-based algorithm to analyze in-vivo confocal microscopy (IVCM) images. MethodsSubbasal nerve plexus (SNP) images of the inferior whorl of patients with DED (n = 49, 77 eyes), NCP (n = 14, 24 eyes), and controls (n = 41, 59 eyes) were taken with IVCM and further analyzed using an open-source artificial intelligence (AI)-based algorithm previously developed by our group. This algorithm automatically segments nerves, immune cells, and neuromas in the SNP. The following parameters were compared between groups: nerve area density, average nerve thickness, average nerve segment tortuosity, junction point density, neuroma density, and immune cell density. Results160 eyes of 104 patients (63 % females), aged 56.8 ± 15.4 years, were included. The mean nerve area density was significantly lower in the DED (P = 0.012) and NCP (P < 0.001) groups compared to the control group. The junction point density was lower in the NCP group compared with control (P = 0.001) and DED (P = 0.004) groups. The immune cell density was higher in the DED group compared with controls (P < 0.001). ConclusionsDeep-learning-based analysis of IVCM images of the corneal SNP inferior whorl distinguished a decreased mean nerve area density in patients with DED and NCP compared with controls and an increased immune cell density in patients with oGVHD- and SS-associated DED. These findings suggest that the inferior whorl could be used as landmark to distinguish between patients with DED and NCP.

Intratumoral Heterogeneity Assessment of the Extracellular Bone Matrix and Immune Microenvironment in Osteosarcoma Using Digital Imaging to Predict Therapeutic Response

The assessment of chemotherapy response in osteosarcoma (OS) based on the average percentage of viable cells is limited, as it overlooks the spatial heterogeneity of tumor cell response (foci of resistant cells), immune microenvironment, and bone microarchitecture. Despite the resulting positive classification for response to chemotherapy, some patients experience early metastatic recurrence, demonstrating that our conventional tools for evaluating treatment response are insufficient. We studied the interactions between tumor cells, immune cells (lymphocytes, histiocytes, and osteoclasts), and bone extracellular matrix (ECM) in 18 surgical resection samples of OS using multiplex and conventional immunohistochemistry (IHC: CD8, CD163, CD68, and SATB2), combined with multiscale characterization approaches in territories of good and poor response (GRT/PRT) to treatment. GRT and PRT were defined as subregions with <10% and ≥10% of viable tumor cells, respectively. Local correlations between bone ECM porosity and density of immune cells were assessed in these territories. Immune cell density was then correlated to overall patient survival. Two patterns were identified for histiocytes and osteoclasts. In poor responder patients, CD68 osteoclast density exceeded that of CD163 histiocytes but was not related to bone ECM load. Conversely, in good responder patients, CD163 histiocytes were more numerous than CD68 osteoclasts. For both of them, a significant negative local correlation with bone ECM porosity was found (P < .01). Moreover, in PRT, multinucleated osteoclasts were rounded and intermingled with tumor cells, whereas in GRT, they were elongated and found in close contact with bone trabeculae. CD8 levels were always low in metastatic patients, and those initially considered good responders rapidly died from their disease. The specific recruitment of histiocytes and osteoclasts within the bone ECM, and the level of CD8 represent new features of OS response to treatment. The associated prognostic signatures should be integrated into the therapeutic stratification algorithm of patients after surgery.

Abstract Tu080: Unique Physiology of Fibroblast and Immune Cells in the Right Ventricle

Introduction: Failure of the right ventricle (RV) is a main component of the morbidity and mortality of pulmonary hypertension (PH). There exists no specific treatment for RV dysfunction and failure and the only cure for many patients (especially in the case of pulmonary arterial hypertension) remains transplantation. This is partially due to the critical lack of understanding of RV biology; therapeutic strategies that are beneficial for LV failure have worse outcomes when applied to those with RV failure. RV dysfunction is characterized by exaggerated fibrosis and divergent contractile and hypertrophic responses to several drugs when compared to LV dysfunction. Thus, the RV may contain distinct cellular physiology compared to the LV that has high significance for the treatment of PH. Methods: Tissue digests from the RV and LV of Sprague Dawley rats were collected. We utilized digests to collect RNA for RNA-seq, and prepared cells for flow cytometry and fibroblast isolations. Fibroblasts were cultured for proliferation assays and cell signaling studies. Results: We found that the RV and LV have significant differences in expression of immune-related and fibrotic genes. The RV of control rats had an average of four-fold higher density of immune cells, namely macrophages/monocytes, compared to the LV (P&lt;0.05 via paired t-test). Fibroblasts from the RV of control rats, which had a higher proliferation rate and an alteration of metabolic genes than those from the LV (P&lt;0.05 via two-way ANOVA), also had a higher fold-change increase in periostin and CTGF expression upon treatment with TGFβ. Conclusions: The results demonstrate that in comparison to the LV, the RV is made up of a unique population of cells and has a unique capacity for fibrotic response that is reflected in its molecular makeup, which may contribute to its distinct response to PH. Future experiments will focus on determining the molecular mechanisms driving these differences. This knowledge is expected to yield new therapeutic approaches for RV dysfunction and failure occurring with PH, which currently have no specific treatment.

Organ-Specific Immune Setpoints Underlie Divergent Immune Profiles across Metastatic Sites in Breast Cancer.

Immune composition within the tumor microenvironment (TME) plays a central role in the propensity of cancer cells to metastasize and respond to therapy. Previous studies have suggested that the metastatic TME is immune-suppressed. However, limited accessibility to multiple metastatic sites within patients has made assessing the immune TME difficult in the context of multiorgan metastases. We utilized a rapid postmortem tissue collection protocol to assess the immune composition of numerous sites of breast cancer metastasis and paired tumor-free tissues. Metastases had comparable immune cell densities and compositions to paired tumor-free tissues of the same organ type. In contrast, immune cell densities in both metastatic and tumor-free tissues differed significantly between organ types, with lung immune infiltration being consistently greater than that in the liver. These immune profiling results were consistent between flow cytometry and multiplex immunofluorescence-based spatial analysis. Furthermore, we found that granulocytes were the predominant tumor-infiltrating immune cells in lung and liver metastases, and these granulocytes comprised most PD-L1-expressing cells in many tissue sites. We also identified distinct potential mechanisms of immunosuppression in lung and liver metastases, with the lung having increased expression of PD-L1+ antigen-presenting cells and the liver having higher numbers of activated regulatory T cells and HLA-DRlow monocytes. Together, these results demonstrate that the immune contexture of metastases is dictated by organ type and that immunotherapy strategies may benefit from unique tailoring to the tissue-specific features of the immune TME.

Platinum-Based Chemotherapy Induces Opposing Effects on Immunotherapy Response-Related Spatial and Stromal Biomarkers in the Bladder Cancer Microenvironment.

Platinum-based chemotherapy and immune checkpoint inhibitors are key components of systemic treatment for muscle-invasive and advanced urothelial cancer. The ideal integration of these two treatment modalities remains unclear as clinical trials have led to inconsistent results. Modulation of the tumor-immune microenvironment by chemotherapy is poorly characterized. We aimed to investigate this modulation, focusing on potential clinical implications for immune checkpoint inhibitor response. We assessed immune cell densities, spatial relations, and tumor/stromal components from 116 patients with urothelial bladder cancer (paired data for 95 patients) before and after platinum-based chemotherapy. Several published biomarkers for immunotherapy response changed upon chemotherapy treatment. The intratumoral CD8+ T-cell percentage increased after treatment and was associated with increased TNFα-via-NF-κB signaling. The percentage of PDL1+ immune cells was higher after chemotherapy. An increase in chemo-induced changes that potentially inhibit an antitumor immune response was also observed, including increased fibroblast-based TGFβ signaling and distances from immune cells to the nearest cancer cell. The latter two parameters correlated significantly in posttreatment samples, suggesting that TGFβ signaling in fibroblasts may play a role in spatially separating immune cells from cancer cells. We examined specific chemotherapy regimens and found that treatment with methotrexate, vinblastine, doxorubicin, and cisplatin was associated with an increase in the macrophage cell percentage. Gemcitabine-containing chemotherapy was associated with upregulation of fibroblast TGFβ signaling. The opposing effects of platinum-based chemotherapy on the immune cell composition and stromal context of the tumor-immune microenvironment may explain the inconsistent results of clinical trials investigating chemotherapy and immune checkpoint inhibitor combinations in bladder cancer.