Tumor-infiltrating Cells Research Articles

Bulk and single-cell transcriptome profiling reveal the metabolic heterogeneity in gastric cancer

Metabolic reprogramming has been defined as a key hall mark of human tumors. However, metabolic heterogeneity in gastric cancer has not been elucidated. Here we separated the TCGA-STAD dataset into two metabolic subtypes. The differences between subtypes were elaborated in terms of transcriptomics, genomics, tumor-infiltrating cells, and single-cell resolution. We found that metabolic subtype 1 is predominantly characterized by low metabolism, high immune cell infiltration. Subtype 2 is mainly characterized by high metabolism and low immune cell infiltration. From single-cell resolution, we found that the high metabolism of subtype 2 is dominated by epithelial cells. Not only epithelial cells, but also various immune cells and stromal cells showed high metabolism in subtype 2 and low metabolism in subtype 1. Our study established a classification of gastric cancer metabolic subtypes and explored the differences between subtypes from multiple dimensions, especially the single-cell resolution.

SOX9 drives KRAS-induced lung adenocarcinoma progression and suppresses anti-tumor immunity.

The SOX9 transcription factor ensures proper tissue development and homeostasis and has been implicated in promoting tumor progression. However, the role of SOX9 as a driver of lung adenocarcinoma (LUAD), or any cancer, remains unclear. Using CRISPR/Cas9 and Cre-LoxP gene knockout approaches in the KrasG12D-driven mouse LUAD model, we found that loss of Sox9 significantly reduces lung tumor development, burden and progression, contributing to significantly longer overall survival. SOX9 consistently drove organoid growth in vitro, but SOX9-promoted tumor growth was significantly attenuated in immunocompromised mice compared to syngeneic mice. We demonstrate that SOX9 suppresses immune cell infiltration and functionally suppresses tumor associated CD8+ T, natural killer and dendritic cells. These data were validated by flow cytometry, gene expression, RT-qPCR, and immunohistochemistry analyses in KrasG12D-driven murine LUAD, then confirmed by interrogating bulk and single-cell gene expression repertoires and immunohistochemistry in human LUAD. Notably, SOX9 significantly elevates collagen-related gene expression and substantially increases collagen fibers. We propose that SOX9 increases tumor stiffness and inhibits tumor-infiltrating dendritic cells, thereby suppressing CD8+ T cell and NK cell infiltration and activity. Thus, SOX9 drives KrasG12D-driven lung tumor progression and inhibits anti-tumor immunity at least partly by modulating the tumor microenvironment.

Toxic and infectious lung injury differential diagnosis specifics in oncohematological patients

Background. Assessment of lung injury in oncohematological patients is a relevant problem, since the spectrum of pathological changes is wide and includes pulmonary infections, tumor cell infiltration, cardiogenic and non-cardiogenic pulmonary edema, bronchiolitis obliterans, interstitial pneumonitis, post-radiation and post-inflammatory pneumofibrosis, pulmonary vasculopathy and pleural effusion. At the moment there are no approved recommendations with criteria of differential diagnosis for these conditions, in particular, with differences between the most common therapy complication represented by pulmonary infections and poorly explored drug-induced toxic lesions.Aim. Identification of criteria for pneumotoxicity, allowing for differential diagnosis with pulmonary infections developing during chemotherapy, according to data routinely obtained in real clinical practice.Materials and methods. The study group included 38 patients with cytotoxic and autoimmune lung injury caused by specific therapy (group 1); the comparison group included 38 patients with infectious lesions receiving the same antitumor drugs (group 2). The data of the anamnesis, clinical course, instrumental studies and standard laboratory tests was studied retrospectively. For statistical analysis, the Mann–Whitney, χ2, Kruskal–Wallis tests were used. ROC analysis was performed to assess the sensitivity and specificity of various factors in relation to toxic damage.Results. Patients with lymphomas predominated in group of toxic lung injury (63 %). In patients who underwent allogeneic hematopoietic stem cells transplantation, toxic complications developed in the period from 35 to 1289 days, infectious – from 4 to 43 days. Statistically significant differences were obtained in the presence of a concomitant state of an altered immune response: 32 % of patients in the toxic lesion group versus 5 % in the infectious group had a history of allergy, and, in contrast to the infectious lesion group, in the toxic lesion group autoimmune diseases were detected. The main symptom in patients of the first group was shortness of breath, which was observed in 68 % of cases, of the second – an increased body temperature, observed in 92 % of cases; cough was also a common symptom – in 19 % and 13 % of patients respectively. In 58 % of patients of the second group, concomitant mucositis was detected, while in the first group this complication did not occur in any of them. The most common radiological pattern (71 % of cases in each group) was ground-glass opacities, in patients of the second group often combined with infiltrative changes and thickening of the bronchial walls (in 53 and 42 % of cases respectively). Among laboratory results, the largest differences between groups were observed in the leukocyte levels (with an average level of 2.5 . 109 / L in the infectious group versus 6 . 109 / L in the toxic group), eosinophils (with an average of 3.6 % in the toxic group versus 1.75 % in the infectious group), C-reactive protein (with an average level of 146.7 mg / L in the infectious group versus 52.4 mg / L in the toxic group), and creatinine (with an average of 0.085 mmol / L in the toxic group versus 0.071 mmol / L in the infectious group).Conclusion. The data obtained in this research indicates the value of taking an anamnesis and the importance of performing additional studies in patients with suspected drug-induced lung injury, as well as identifies risk groups. Based on the revealed differences, a scale for the differential diagnosis of drug-induced toxic and infectious lung damage, which includes the results of publicly available research methods, with high sensitivity and specificity, was proposed. Further research for more specific, but, at the same time, universal for various drugs, criteria for toxic lung damage is relevant.

Everolimus combined with PD-1 blockade inhibits progression of triple-negative breast cancer

Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer. Due to rapid progression and a lack of targetable receptors, TNBC is exceptionally difficult to treat. Available treatment options are nonspecific cytotoxic agents, which have had modest success; thus, there is a need for novel therapies for TNBC. The mammalian/mechanistic target of rapamycin (mTOR) signaling pathway is aberrantly activated in TNBC, and this pathway has been shown to promote cancer cell survival and chemoresistance. As such, mTOR inhibition has been considered a potential therapeutic strategy for TNBC. The mTOR inhibitor everolimus (EVE) has been approved for the treatment of estrogen positive breast cancer; however, its efficacy in TNBC is still undetermined. In this study, we evaluated the effects of EVE monotherapy and the mechanism of EVE resistance in the 4T1 model of TNBC. Whereas EVE monotherapy inhibited mTOR signaling activity, it did not attenuate tumor progression. Additionally, tumors from EVE-treated mice had abnormal vasculature characterized by disorganized architecture and hyperpermeability. We also found that treatment with EVE increased PD-L1 expression in intratumoral vascular endothelial cells, and this increase in endothelial cell-associated PD-L1 corresponded to reduced CD8 + T cell tumor infiltration. Importantly, combination treatment with anti-PD-1 antibody and EVE normalized the tumor vasculature, rescued CD8 + T cell tumor infiltration, and reduced tumor growth. Taken together, our findings improve our current understanding of mechanisms underlying mTOR inhibition resistance in TNBC and identify a novel combination treatment strategy in the treatment of mTOR resistant tumors.

Prognostic, Immunological, and Mutational Analysis of MTA2 in Pan-Cancer and Drug Screening for Hepatocellular Carcinoma.

Metastasis-associated protein 2 (MTA2) is a member of the metastasis-associated transcriptional regulator family and is a core component of the nucleosome remodeling and histone deacetylation complex. Despite growing evidence that MTA2 plays a crucial role in the tumorigenesis of certain cancers, no systematic pan-cancer analysis of MTA2 is available to date. Therefore, the aim of our study is to explore the prognostic value of MTA2 in 33 cancer types and to investigate its potential immune function. by comprehensive use of databases from TCGA, GTEx, GEO, UCSC xena, cBioPortal, comPPI, GeneMANIA, TCIA, MSigDB, and PDB, we applied various bioinformatics approaches to investigate the potential role of MTA2, including analyzing the association of MTA2 with MSI, prognosis, gene mutation, and immune cell infiltration in different tumors. We constructed a nomogram in TCGA-LIHC, performed single-cell sequencing (scRNA-seq) analysis of MTA2 in hepatocellular carcinoma (HCC), and screened drugs for the treatment of HCC. Finally, immunohistochemical experiments were performed to verify the expression and prognostic value of MTA2 in HCC. In vitro experiments were employed to observe the growth inhibition effects of MK-886 on the HCC cell line HepG2. The results suggested that MTA2 was highly expressed in most cancers, and MTA2 expression was associated with the prognosis of different cancers. In addition, MTA2 expression was associated with Tumor Mutation Burden (TMB) in 12 cancer types and MSI in 8 cancer types. Immunoassays indicated that MTA2 positively correlated with activated memory CD4 T cells and M0 macrophage infiltration levels in HCC. ScRNA-seq analysis based on the GEO dataset discovered that MTA2 was significantly expressed in T cells in HCC. Finally, the eXtreme Sum (Xsum) algorithm was used to screen the antitumor drug MK-886, and the molecular docking technique was utilized to reveal the binding capacity between MK-886 and the MTA2 protein. The results demonstrated excellent binding sites between them, which bind to each other through Π-alkyl and alkyl interaction forces. An immunohistochemistry experiment showed that MTA2 protein was highly expressed in HCC, and high MTA2 expression was associated with poor survival in HCC patients. MK-886 significantly inhibited the proliferation and induced cell death of HepG2 cells in a dose-dependent manner. Our study demonstrated that MTA2 plays crucial roles in tumor progression and tumor immunity, and it could be used as a prognostic marker for various malignancies. MK-886 might be a powerful drug for HCC.

Polydatin radiosensitizes lung cancer while preventing radiation injuries by modulating tumor-infiltrating B cells

BackgroundAcquired radio-resistance and the undesired normal tissue radiation injuries seriously discount the therapeutic effect of lung cancer radiotherapy. In this study, we aimed to explore the role and potential mechanism of polydatin in simultaneously decreasing radioresistance and radiation injuries.MethodsThe tumor-bearing model of nude mice was used to investigate the tumor inhibition of polydatin on lung cancer and its effect on radiosensitivity, and the effect of polydatin on B cell infiltration in cancerous tissue was investigated. In addition, we performed systemic radiotherapy on BABL/C mice and evaluated the protective effect of polydatin on radiation injury by the Kaplan–Meier survival curve. Moreover, the regulation of polydatin on proliferation and apoptosis of A549 cells was also investigated in vitro.ResultsIn this study, it is first found that polydatin inhibits the growth and promotes the radiosensitivity of lung cancer while reducing the radiation damage of the healthy tissue. Further, it is evidenced that the major mechanism relies on its regulation on body’s immune function, and in particular, the inhibition of radiation-induced B cell infiltration in tumor tissue.ConclusionThese findings show that in addition to tumor inhibition, polydatin also promotes the sensitivity and reduces the adverse reactions of radiotherapy, making itself a promising candidate for boosting lung cancer radiotherapy efficacy.

Identification of cuproptosis‐related subtypes and tumor microenvironment characteristics in colon cancer

AbstractCuproptosis is a form of regulated cell death, which is characterized by the lethal accumulation of excessive copper in cells. However, its role in colon adenocarcinoma (COAD) remains elusive. Our study aimed to decipher the biological function of cuproptosis‐related genes (CRGs) in patients with COAD. The expression data were obtained from The Cancer Genome Atlas, while the Gene Expression Omnibus database was used to verify the results. A total of eight differentially expressed CRGs were selected from patients with COAD. Subsequently, patients were stratified into three subtypes with distinct clinical and biological features. In view of the huge differences in the prognosis between subtypes A and C, we selected them for further study, including the variations in clinical progressions, oncogenic pathways, and immune cell infiltration. For the sake of better evaluation, we also established a cuproptosis index (CI) to quantify the heterogeneity of CRGs expression. Enrichment analysis showed that the high‐CI group was enriched in immune activation pathways. Meanwhile, the immunosuppressive cell infiltration and immune checkpoints were elevated in the high‐CI group. The CI we constructed had its predicting function in different clinical groups. Besides, we noticed that CRGs, especially CDKN2A, were closely related to the clinical progression in patients with COAD and immune cell infiltration in tumors. Moreover, CDKN2A could become a potential novel target for immunotherapy in the setting of COAD.

Awakening Allies for Breaking Microenvironment Barriers: NIR-II Guided Orthogonal Activation of Tumor-infiltrating Mast Cells for Efficient Nano-drug Delivery.

Mast cells (MCs), powerful immune cells that heavily infiltrate cancer cells, play a crucial role in tumor formation. Activated MCs can release histamine and a family of proteases through degranulation effects, concurrently achieving endothelial junction weakening and stromal degradation of the tumor microenvironment, thereby clearing the obstacles for nano-drug infiltration. To achieve precise activation of tumor-infiltrating MCs, orthogonally excited rare earth nanoparticles (ORENP), with two channels, have been introduced for the controllable stimulating drugs release wrapped in "photocut tape." The ORENP can emit near-infrared II (NIR-II) for image tracing for tumor localization in Channel 1 (808/NIR-II) and allows energy upconversion to emit ultraviolet (UV) light for releasing drugs for MCs stimulation in Channel 2 (980/UV). Finally, the combined use of chemical and cellular tools enables clinical nano-drugs to achieve a significant increase in tumor infiltration, thereby enhancing the efficacy of nano-chemotherapy. This article is protected by copyright. All rights reserved.

Association of Tumor Cell Metabolic Subtype and Immune Response With the Clinical Course of Hepatocellular Carcinoma.

Tumor metabolism plays an important role in tumorigenesis and tumor progression. This study evaluated the potential association of tumor cell metabolism and immune cell tumor infiltration with the clinical course of hepatocellular carcinoma (HCC). Gene-wise normalization and principal component analysis were performed to evaluate the metabolic system. A tumor microenvironment score system of tumor immune cell infiltration was constructed to evaluate its association with metabolic subtypes. Finally, we analyzed the impact of metabolism and immune cell infiltration on the clinical course of HCC. A total of 673 HCC patients were categorized into cholesterogenic (25.3%), glycolytic (14.6%), mixed (10.4%), and quiescent (49.8%) types based on glycolysis and cholesterol biosynthesis gene expression. The subgroups including the glycolytic genotyping expression (glycolytic and mixed types) showed a higher mortality rate. The glycolytic, cholesterogenic, and mixed types were positively correlated with M0 macrophage, resting mast cell, and naïve B-cell infiltration (P = .013, P = .019, and P = .006, respectively). In TCGA database, high CD8+ T cell and low M0 macrophage infiltration were associated with prolonged overall survival (OS, P = .0017 and P < .0001, respectively). Furthermore, in glycolytic and mixed types, patients with high M0 macrophage infiltration had a shorter OS (P = .03 and P = .013, respectively), and in quiescent type, patients with low naïve B-cell infiltration had a longer OS (P = .007). Tumor metabolism plays a prognostic role and correlates with immune cell infiltration in HCC. M0 macrophage and CD8+ T cell appear to be promising prognostic biomarker for HCC. Finally, M0 macrophages may represent a useful immunotherapeutic target in patients with HCC.

A novel PD-1/PD-L1 pathway molecular typing-related signature for predicting prognosis and the tumor microenvironment in breast cancer

BackgroundCurrently, the development of breast cancer immunotherapy based on the PD-1/PD-L1 pathway is relatively slow, and the specific mechanism affecting the immunotherapy efficacy in breast cancer is still unclear.MethodsWeighted correlation network analysis (WGCNA) and the negative matrix factorization (NMF) were used to distinguish subtypes related to the PD-1/PD-L1 pathway in breast cancer. Then univariate Cox, least absolute shrinkage and selection operator (LASSO), and multivariate Cox regression were used to construct the prognostic signature. A nomogram was established based on the signature. The relationship between the signature gene IFNG and breast cancer tumor microenvironment was analyzed.ResultsFour PD-1/PD-L1 pathway-related subtypes were distinguished. A prognostic signature related to PD-1/PD-L1 pathway typing was constructed to evaluate breast cancer’s clinical characteristics and tumor microenvironment. The nomogram based on the RiskScore could be used to accurately predict breast cancer patients’ 1-year, 3-year, and 5-year survival probability. The expression of IFNG was positively correlated with CD8+ T cell infiltration in the breast cancer tumor microenvironment.ConclusionA prognostic signature is constructed based on the PD-1/PD-L1 pathway typing in breast cancer, which can guide the precise treatment of breast cancer. The signature gene IFNG is positively related to CD8+ T cell infiltration in breast cancer.

Carotid Sheath Dissection and Histopathology During Neck Dissection in Head and Neck Carcinomas.

To investigate the carotid sheath in neck dissection (ND) specimens histopathologically in patients with head and neck carcinomas who had no evidence of previous neck surgery or direct involvement of the carotid sheath in their pre- or intra-operative evaluations. In this study, carotid sheath (CS) specimens of 40 patients with head and neck carcinomas (HNCA) who, depending on the condition of the primary tumor, required unilateral or bilateral elective or therapeutic selective neck dissection were histopathologically investigated by an expert head and neck pathologist to find any lymphoid or thyroid like tissue or tumor cells infiltration. A total of 50 carotid sheath (CS) specimens were investigated. None of the samples showed any evidence of tumor infiltration or accumulation of lymphatic tissue. We conclude that in patients with no histopathologic involvement of the carotid sheath in pre-operative or intra-operative tumor invasion, it is not necessary to remove CS in routine neck dissection.

Location and condition based reconstruction of colon cancer microbiome from human RNA sequencing data

BackgroundThe association between microbes and cancer has been reported repeatedly; however, it is not clear if molecular tumour properties are connected to specific microbial colonisation patterns. This is due mainly to the current technical and analytical strategy limitations to characterise tumour-associated bacteria.MethodsHere, we propose an approach to detect bacterial signals in human RNA sequencing data and associate them with the clinical and molecular properties of the tumours. The method was tested on public datasets from The Cancer Genome Atlas, and its accuracy was assessed on a new cohort of colorectal cancer patients.ResultsOur analysis shows that intratumoural microbiome composition is correlated with survival, anatomic location, microsatellite instability, consensus molecular subtype and immune cell infiltration in colon tumours. In particular, we find Faecalibacterium prausnitzii, Coprococcus comes, Bacteroides spp., Fusobacterium spp. and Clostridium spp. to be strongly associated with tumour properties.ConclusionsWe implemented an approach to concurrently analyse clinical and molecular properties of the tumour as well as the composition of the associated microbiome. Our results may improve patient stratification and pave the path for mechanistic studies on microbiota-tumour crosstalk.

CD69 on Tumor-Infiltrating Cells Correlates With Neuroblastoma Suppression by Simultaneous PD-1 and PD-L1 Blockade

IntroductionTumor-infiltrating cells play an important role in tumor immunology, and tumor-infiltrating lymphocytes (TILs) are critical in antitumor reaction related to immune checkpoint inhibition targeting programmed cell death protein 1 (PD-1) and programmed cell death ligand 1 (PD-L1). MethodsIn nude mice, which are immune deficient because they lack T cells, and inbred A/J mice, which are syngeneic to neuroblastoma cells (Neuro-2a) and have normal T cell function, we investigated the importance of T lymphocytes in immune checkpoint inhibition in mouse neuroblastoma and analyzed the immune cells in the tumor microenvironment. Then, we subcutaneously injected mouse Neuro-2ainto nude mice and A/J mice, administered anti-PD-1 and anti-PD-L1 antibodies by intraperitoneal injection, and evaluated tumor growth. At 16 d after Neuro-2a cells injection, mice were euthanized, tumors and spleens were harvested, and immune cells were analyzed by flow cytometry. ResultsThe antibodies suppressed tumor growth in A/J but not in nude mice. The co-administration of antibodies did not affect regulatory T cells (culster of differentiation [CD]4+CD25+FoxP3+ cells) or activated CD4+ lymphocytes (expressing CD69). No changes in activated CD8+ lymphocytes (expressing CD69) were observed in spleen tissue. However, increased infiltration of activated CD8+ TILs was seen in tumors weighing less than 300 mg, and the amount of activated CD8+ TILs was negatively correlated with tumor weight. ConclusionsOur study confirms that lymphocytes are essential for the antitumor immune reaction induced by blocking PD-1/PD-L1 and raises the possibility that promoting the infiltration of activated CD8+ TIL into tumors may be an effective treatment for neuroblastoma.

Endogenously high Omega-3 levels lead to a less suppressive tumor microenvironment

Abstract Cellular transformation leading to cancer development involves multiple changes in the cellular pool of nutrients and macromolecules, including lipids. Tumors switch to the de novo lipid pathway and preferentially accumulate some lipids while excluding others, such as omega-3 (n-3) fatty acids and bioactive lipids derived from them, from the tumor microenvironment. These lipids, known as specialized pro-resolving lipids (SPM), may affect cancer development. Although their roles in decreased cancer risk and overall inflammation are well studied, their effects on anti-tumor immunity are still poorly understood. Here, we report the consequences of high n-3 levels on tumor growth and anti-tumor immunity. We have utilized a FAT-1 transgenic mouse model with an endogenously high n-3: n-6 ratio due to a transgenic enzyme making n-3 fatty acids and EO771 mammary tumor model. Our data show a decreased tumor growth rate in FAT-1 mice associated with increased tumor-infiltrating cells (TILs). In preliminary studies, we further discovered that CD8 and CD4 T-cells in TILs isolated from tumors growing in FAT-1 mice display a more active and proliferative phenotype. Also, the T-cells had decreased exhaustion markers such as TIM-3, LAG-3, and TIGIT in the TILs isolated from tumors growing in FAT-1 animals, and there were fewer FOXP-3 positive T-cells. Together our data suggest a less suppressive anti-tumor immune environment in FAT-1 animals. Currently, we are performing mechanistic studies to understand the role of high omega-3 in the expression and function of these exhaustion markers. We are also exploring the therapeutic benefit of checkpoint inhibitors and cancer vaccines in combination with high omega-3 fatty acids.

Tumor infiltrating natural killer cells in soft tissue sarcoma are predominantly CD56 dim: Implications for outcomes

Abstract Natural killer (NK) cells have been shown to be important mediators of anti-tumor responses, including in soft tissue sarcomas (STS). NK cells show significant heterogeneity, depending on maturation, tissue residency, and inflammatory environment. As previous studies have suggested that tumor-infiltrating NK cells (TiNKs) acquire a less cytotoxic CD56 brighttissue resident phenotype, we sought to compare blood versus tumor NK cell phenotype in STS and evaluate any association with survival. Blood and tumor from 27 STS patients undergoing surgery from 2018–2022 were collected prospectively for flow cytometry and retrospectively analyzed. 52% were female, the mean age was 59, and 74% were AJCC stage 3. Increasing absolute number of NK cells in the blood correlated with longer survival (P&amp;lt;0.005, r=0.6). As expected, CD56 dimNK cells predominated in the blood (91.5±5.8% of CD3-CD56+ lymphocytes compared to 80.1±13% in tumor, P&amp;lt;0.005). In contrast, CD56 brightcells were enriched in tumor representing 18.5±13% compared to 8.4±5.8% in blood (P&amp;lt;0.005). Although CD56 brightNK cells were approximately 2.4±3-fold higher in tumor compared to blood, CD56 dimNK cells still represented the majority of TiNKs. Higher proportions of both overall NK cells and CD56 dimNK cells in STS tumors were associated with better metastasis-free survival on Kaplan-Meier analysis (P&amp;lt;0.05). CD56 dimTiNKs had higher NKp46 expression than CD56 brights. In conclusion, both blood and intra-tumoral NK cells appear prognostic in STS. Although the proportion of CD56 brightTiNKs in STS is higher than blood the majority of TiNKs are CD56 dimconsistent with a cytotoxic phenotype. Better characterization of NK subsets in STS is likely to have translational significance.

Mass cytometry analysis of mouse nonclassical monocyte heterogeneity in breast tumors

Abstract Monocytes have emerged as important regulators of cancer progression. Our previous studies demonstrated the importance of nonclassical Ly6C lomonocytes in regulating cancer metastasis in mouse models. Here, we aimed to study monocyte heterogeneity in two different breast cancer tumors in mice using either 4T1 or EMT6 cells. 4T1 tumors exhibit an increased ability to metastasize in the lung in a BALB/c mouse breast cancer model compared to the less aggressive EMT6 tumor model. We evaluated 35 surface markers of tumor-infiltrated monocytes and dendritic cells in tumors isolated from each model using CyTOF mass cytometry. Analysis of monocytes and dendritic cells in the tumors using the Seurat package and the FlowSom algorithm identified 12 cell subsets. Significant differences were discovered between the two tumor types in frequencies of four of 12 identified subsets. However, only one of these subsets, a nonclassical monocyte subset, was higher in the less metastatic EMT6 tumors. This subset was 5-fold higher in EMT6 tumors versus more aggressive 4T1 tumors. This Ly6C lononclassical monocyte subset showed high expression of CD169 and CX3CR1, CD86 and CD80. These differentially expressed markers suggest a functional importance in this subset in migration to the tumor and antigen presentation, both of which are anti-tumoral functions. Ongoing studies are aimed towards understanding the role of this non-classical monocyte population in regulating breast cancer metastasis. This work was supported by NIH R01 CA202987, and P01 HL136275

Single-cell RNA sequencing reveals heterogeneous immune landscape of tumor-infiltrating lymphocytes in the glioblastoma tumor microenvironment in the absence of IFNAR

Abstract Glioblastoma (GBM) is known to be the most common malignant brain cancer with a very poor prognosis. Despite standard conventional therapies patient survival rates still remain poor and reasons for this may be due to the extensive tumor cellular heterogeneity of the tumor microenvironment. Type I interferons (IFNs) are a family of cytokines produced by multiple cell types and are known to play a role in anticancer immunity through their signaling via the interferon alpha receptor (IFNAR). We find that absence of IFNAR compromises anti-tumor immunity against GBM. Single-cell RNA analysis of the immune landscape of GBM tumor-bearing IfnαR−/−mice reveals that there is an overall decrease in tumor-infiltrating lymphocytes into the brain along with overall decreased expression of IFNγ, TNFα, and Granzyme A. Analysis of lymphoid cells including T cells and NK cells shows substantial decreased infiltration in the presence of GBM in IFNαR deficient mice. Notably, CD4 and CD8 T cell infiltration is considerably reduced, although how the functions of these cells are affected is yet unknown. Analysis of tumor-infiltrating myeloid cells in the absence of interferon signaling reveals decreased infiltration of monocytes and tumor-associated macrophages as well. Thus, in this study, we are able to see that the absence of type I interferon signaling affects the overall recruitment of lymphoid and myeloid cells during the progression of GBM and likely contributes to the exacerbation of anti-tumor immunity.

Immune modulations of the tumor microenvironment in response to phototherapy.

The tumor microenvironment (TME) promotes pro-tumor and anti-inflammatory metabolisms and suppresses the host immune system. It prevents immune cells from fighting against cancer effectively, resulting in limited efficacy of many current cancer treatment modalities. Different therapies aim to overcome the immunosuppressive TME by combining various approaches to synergize their effects for enhanced anti-tumor activity and augmented stimulation of the immune system. Immunotherapy has become a major therapeutic strategy because it unleashes the power of the immune system by activating, enhancing, and directing immune responses to prevent, control, and eliminate cancer. Phototherapy uses light irradiation to induce tumor cell death through photothermal, photochemical, and photo-immunological interactions. Phototherapy induces tumor immunogenic cell death, which is a precursor and enhancer for anti-tumor immunity. However, phototherapy alone has limited effects on long-term and systemic anti-tumor immune responses. Phototherapy can be combined with immunotherapy to improve the tumoricidal effect by killing target tumor cells, enhancing immune cell infiltration in tumors, and rewiring pathways in the TME from anti-inflammatory to pro-inflammatory. Phototherapy-enhanced immunotherapy triggers effective cooperation between innate and adaptive immunities, specifically targeting the tumor cells, whether they are localized or distant. Herein, the successes and limitations of phototherapy combined with other cancer treatment modalities will be discussed. Specifically, we will review the synergistic effects of phototherapy combined with different cancer therapies on tumor elimination and remodeling of the immunosuppressive TME. Overall, phototherapy, in combination with other therapeutic modalities, can establish anti-tumor pro-inflammatory phenotypes in activated tumor-infiltrating T cells and B cells and activate systemic anti-tumor immune responses.

The prognostic significance of non-lymphoid immune cells of the tumor microenvironment, including neutrophils, eosinophils, and mast cells in breast carcinomas

Background and objectiveThe prognostic importance of lymphoid cells in the tumor microenvironment and their effect on treatment response have been demonstrated in many cancer types. However, there are limited studies on non-lymphoid immune cells. Conflicting results have been obtained regarding the effects of these cells on prognosis. Materials and methodsA total of 331 patients who underwent surgery for breast cancer were included. Patients that received neoadjuvant chemotherapy and those with distant metastasis were excluded. CD 15 immunohistochemistry was performed to detect tumor-infiltrating neutrophils (TINs) and eosinophils (TIEs), while Toluidine Blue histochemistry was performed to detect tumor-infiltrating mast cells (TIMs). ResultsHigh TINs were statistically associated with low ER expression (p < 0.001), low PR expression (p = 0.001), high Ki-67 proliferation index (p = 0.008), and HER2/TN molecular subtypes (p = 0.001). High TIEs were associated with low ER expression (p = 0.001), high Ki67 proliferation index (p = 0.005), and HER2/TN molecular subtype (p = 0.002). High TIMs were associated with high PR expression (p = 0.024), low Ki-67 proliferation index (p = 0.003), and high survival rate (p = 0.006). TIMs and TIEs were good prognostic factors for overall survival in Luminal A and Luminal B subtypes, while TINs and TIEs were found to be independent risk factors for disease-free survival. ConclusionThe evaluation of components of the tumor microenvironment including TINs, TIEs, and TIMs is easy and practical. High TIMs and TIEs are independent prognostic factors, especially in luminal molecular subtype of invasive breast carcinoma. However, to use this parameter in routine pathology practice, more studies from different centers and standard evaluation are needed.

COPS6 promotes tumor progression and reduces CD8+ T cell infiltration by repressing IL-6 production to facilitate tumor immune evasion in breast cancer.

Due to poor T cell infiltration, tumors evade immune surveillance. Increased CD8+ T cell infiltration in breast cancer suggests a satisfactory response to immunotherapy. COPS6 has been identified as an oncogene, but its role in regulating antitumor immune responses has not been defined. In this study, we investigated the impact of COPS6 on tumor immune evasion in vivo. Tumor transplantation models were established in C57BL/6 J mice and BALB/c nude mice. Flow cytometry was conducted to identify the role of COPS6 on tumor-infiltrating CD8+ T cells. By analyzing the TCGA and GTEx cohort, we found that COPS6 expression was significantly up-regulated in a variety of cancers. In human osteosarcoma cell line U2OS and non-small cell lung cancer cell line H1299, we showed that p53 negatively regulated COPS6 promoter activity. In human breast cancer MCF-7 cells, COPS6 overexpression stimulated p-AKT expression as well as the proliferation and malignant transformation of tumor cells, whereas knockdown of COPS6 caused opposite effects. Knockdown of COPS6 also significantly suppressed the growth of mouse mammary cancer EMT6 xenografts in BALB/c nude mice. Bioinformatics analysis suggested that COPS6 was a mediator of IL-6 production in the tumor microenvironment and a negative regulator of CD8+ T cell tumor infiltration in breast cancer. In C57BL6 mice bearing EMT6 xenografts, COPS6 knockdown in the EMT6 cells increased the number of tumor-infiltrating CD8+ T cells, while knockdown of IL-6 in COPS6KD EMT6 cells diminished tumor infiltrating CD8+ T cells. We conclude that COPS6 promotes breast cancer progression by reducing CD8+ T cell infiltration and function via the regulation of IL-6 secretion. This study clarifies the role of p53/COPS6/IL-6/CD8+ tumor infiltrating lymphocytes signaling in breast cancer progression and immune evasion, opening a new path for development of COPS6-targeting therapies to enhance tumor immunogenicity and treat immunologically "cold" breast cancer.