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PubMed2025

Immune landscape and novel therapeutic targets of epidermal growth factor receptor and anaplastic lymphoma kinase wild type never-smoker lung adenocarcinoma.

BACKGROUND: Never-smoker lung adenocarcinoma (NSLA) exhibits distinct immunosuppressive profiles and a lower tumor mutation burden compared with lung adenocarcinoma in smokers. These correlate with poor responses to immune checkpoint inhibitors. In this study, we aimed to elucidate the tumor-immune microenvironment of NSLA without epidermal growth factor receptor (EGFR) or anaplastic lymphoma kinase (ALK) alterations and identify novel therapeutic targets. METHODS: We analyzed genome, transcriptome, and proteomic data from 102 NSLA tumor samples and 16 normal adjacent tissues. We classified tumors into distinct immune clusters (IC) based on gene signatures by profiling the tumor-infiltrating immune cells. RESULTS: The tumors were stratified into three ICs: hot, intermediate, and cold. Notably, only 21 (20.6%) patients exhibited hot IC enriched in cytotoxic T cells, natural killer cells, and B-cell signatures, which correlated with improved recurrence-free survival. Cold ICs (37.3%) exhibited higher myeloid-derived suppressor cell (MDSC) levels and M2 macrophage signatures, with poor immune cell infiltration and relatively low stimulatory cytokines and chemokines expression. CEACAM1, and NECTIN2 were upregulated in intermediate and cold ICs and correlated with MDSC and M2 macrophage infiltration. High expression of these genes was associated with poor survival outcomes. Protein-protein network analysis of 20 upregulated molecules associated with cancer- and driver-related proteins in cold IC identified XPO 1 as a key component. CONCLUSION: Our proteogenomic analysis highlighted the immunosuppressive properties of NSLA without EGFR and ALK alterations and identified novel therapeutic targets. These findings may provide novel treatment strategies that could improve the clinical outcomes of patients with NSLA.

Humans↗

PubMed2026

Distinct spatial immune microenvironment features of different EGFR mutation subtypes in early-stage lung adenocarcinoma.

Epidermal growth factor receptor (EGFR) mutations are common in lung adenocarcinoma (LUAD), yet their influence on the spatial tumor immune microenvironment (TIME) in early-stage disease remains unclear. We characterized the spatial TIME in 144 treatment-naïve, early-stage LUADs using integrated genomic sequencing and multiplex immunohistochemistry (mIHC). Although EGFR-mutant tumors overall displayed reduced CD8 + T-cell infiltration compared with EGFR-wild-type tumors, substantial heterogeneity was observed among EGFR subtypes. Specifically, L858R and rare-variant subtypes exhibited higher tumor mutational burden, greater CD8 + T-cell density, and enrichment of T-cell-dominant cellular neighborhoods relative to 19del subtype, consistent with a comparatively immune-infiltrated phenotype. In contrast, 19del tumors showed lower T-cell infiltration. TP53 co-mutation was also associated with enhanced CD8 + T-cell infiltration. These cross-sectional findings identify hypothesis-generating spatial immune phenotypes across EGFR-mutant LUAD subtypes; their potential relevance to perioperative treatment selection requires prospective validation in outcome-annotated treatment cohorts.

Humans↗

PubMed2026

Manual, digital, and AI tumour-infiltrating lymphocyte scoring: a secondary analysis of the APHINITY randomised trial.

BACKGROUND: Stromal tumour-infiltrating lymphocytes (sTILs) are prognostic in early-stage HER2-positive breast cancer, but their role in the context of dual HER2 blockade remains undefined. We evaluated manual, digital, and artificial intelligence (AI)-based sTIL quantification, together with AI-derived spatial metrics, for prognostic and treatment-benefit stratification using tumour samples from the phase 3 APHINITY trial. METHODS: In the APHINITY trial, 4805 patients were randomly assigned to receive chemotherapy plus trastuzumab with pertuzumab or chemotherapy plus trastuzumab with placebo. Median follow-up was 74·1 months (IQR 68·3-75·4). We analysed 4262 haematoxylin and eosin-stained images using manual assessment, an automated digital approach, AI-based lymphocyte quantification (AI percentage lymphocytes), and two AI-derived spatial features (AI-TIL and immune hotspot). Interobserver reproducibility was assessed in 262 randomly chosen tumour samples scored independently by five pathologists. Multivariable Cox models were used to assess associations between TIL levels and invasive disease-free survival (primary outcome in APHINITY), distant recurrence-free interval, and overall survival. The heterogeneity of pertuzumab benefit was evaluated using subgroup analyses, subpopulation treatment effect pattern plot analyses, and nested Cox models with treatment-by-biomarker interaction terms. FINDINGS: Manual scoring showed high interobserver reproducibility (intraclass correlation coefficient 0·84 [95% CI 0·79-0·88]). Concordance between manual and automated methods was modest. AI-based scoring (AI percentage lymphocytes) reclassified 120 (11·6%) of 1035 node-positive tumours from immune-low (by manual scoring) to immune-high; this subgroup of patients showed greater separation of 5-year invasive disease-free survival curves between pertuzumab and placebo groups compared with patients whose tumours were concordantly classified as immune-low by both manual and AI-based approaches. Higher levels of TILs were associated with improved invasive disease-free survival for all sTIL measurement approaches and spatial measurements (hazard ratios [HRs] 0·41-0·93). Pertuzumab was associated with improved invasive disease-free survival at higher sTIL levels across all measurement approaches (HRs 0·36-0·48), but was not associated with higher values of spatial measures. The largest 6-year absolute improvements with pertuzumab were observed in patients with node-positive disease whose tumours scored in the highest level of immune infiltration of manual sTIL scoring (≥70·0%; mean absolute improvement 12·1 percentage points [SD 2·8]). In nested prognostic and predictive models, AI-based immune hotspot scores provided the most consistent additional information when combined with any sTIL measurement (all p<0·010). INTERPRETATION: Standardised manual sTIL scoring was reproducible, and digital and AI-based methods showed consistent prognostic stratification and potential for treatment-benefit stratification despite only modest correlation between platforms. AI spatial metrics provided complementary information beyond sTIL density and could support more scalable immune assessment. Future studies are needed to validate these approaches in independent cohorts and to clarify their clinical utility for stratifying contemporary HER2-directed therapies. FUNDING: None.

Humans↗

PubMed2026

Artificial intelligence-based tumour infiltrating lymphocyte quantification in patients with triple-negative breast cancer: an independent validation study.

BACKGROUND: Tumour-infiltrating lymphocytes (TILs) are a robust prognostic marker in patients with triple-negative breast cancer. Artificial intelligence (AI)-derived computational tools assessing TILs could improve efficiency, but require independent validation against clinical outcomes. We aimed to compare the prognostic performance of AI-derived TIL scores with pathologist-scored TILs in a large, prospectively collected dataset pooled from randomised controlled trials. METHODS: CATALINA was an independent, external validation study using prospectively collected long-term clinical outcome data pooled from seven randomised clinical trials conducted at multiple sites. We independently evaluated two previously validated AI pipelines that generate five computationally assessed tumour-infiltrating lymphocyte (cTIL) scores by masked, independent deployment of locked models. cTIL scores were correlated with the mean of the pathologist-scored stromal TILs (sTILs) in 220 digitised haematoxylin and eosin whole slide images in a cohort of patients with early-stage triple-negative or HER-2 positive breast cancer, previously scored by trained pathologists in a TIL-reproducibility study. Prognostic performance was assessed in a separate cohort of patients with early triple-negative breast cancer pooled from seven prospective, randomised adjuvant trials. Multivariable Cox regression models adjusted for clinicopathological factors and study heterogeneity assessed associations of cTIL score and sTIL score with invasive disease-free survival, distant disease-free survival, and overall survival. 5-year discrimination was estimated using time-dependent area under the receiver operating characteristic curve (AUC). FINDINGS: Individual data were collated from 1759 patients, of whom 1356 had complete clinicopathological data, pathologist sTIL scores, and cTIL scores available. Modest correlation (r 0·375-0·473) was observed between cTIL scores and the mean pathologist sTIL score. Both sTIL and cTIL were independently associated with 5-year invasive disease-free survival, distant disease-free survival, and overall survival after adjustment for clinicopathological factors (hazard ratio for invasive disease-free survival was 0·73 [95% CI 0·66-0·82]; q<0·0001, distant disease-free survival was 0·70 [0·61-0·79]; q<0·0001, and overall survival was 0·72 [0·63-0·82]; q<0·0001 for sTIL scores and 0·80 [0·73-0·89]; q<0·0001, 0·77 [0·69-0·86]; q<0·0001, and 0·79 [0·70-0·88]; q=0·0002, respectively, for percentage_lymphocyte scores). In models adjusted for clinicopathological variables and sTIL score, cTIL score did not maintain a statistically significant prognostic association. Both sTIL and cTIL scores improved the 5-year AUC over clinicopathological variables alone, while cTIL score did not significantly further improve AUC when combined with clinicopathological variables and sTIL score. INTERPRETATION: Two cTIL models deployed entirely without retraining or modification provided statistically significant prognostic information and improved risk discrimination compared with clinicopathological variables alone in this large, platform-based, independent validation study. Although cTIL score did not incrementally improve prognostication compared with models combining clinicopathological variables with sTIL score, these findings support the application of cTILs as a reproducible prognostic biomarker, particularly in settings where routine or widespread pathologist assessment is unavailable. FUNDING: Breast Cancer Research Foundation (USA).

Humans↗

PubMed2025

Progressive T cell exhaustion and predominance of aging tissue associated macrophages with advancing disease stage in penile squamous cell carcinoma.

Penile squamous cell carcinoma (PSCC) is a rare malignancy with limited understanding of the tumor immune microenvironment (TIME). The interplay between PSCC and the immune system across disease progression and HPV infection status remains poorly characterized. This study aims to assess the TIME changes from localized to advanced disease and between HPV-positive versus negative tumors to identify potential immune evasion mechanisms in advanced PSCC. scRNA-seq was performed on ten PSCC tissue samples from penile, lymph node and distant metastatic sites with four matched penile and lymph node samples to understand the cellular heterogeneity within PSCC tumors. Analysis of immune cell populations and transcriptional hallmarks were performed stratified by localized (pT1-3, N0) versus advanced (N1-3, M0 or any N, M1) disease states and HPV infection status. We observed significant differences in immune cell infiltration between localized and advanced PSCC disease states and by HPV status. Advanced disease states demonstrated an exhausted immune phenotype, characterized by terminally exhausted CD8+ T cells, M2-like macrophages and hypoxic signature, while localized disease states demonstrated an active innate immune system characterized by increased DCs. HPV-negative tumors displayed low immune cell infiltration while HPV-positive tumors demonstrated an immune exhausted phenotype. These findings offer valuable insights into the evolving PSCC immune landscape, paving the way for the development of potential therapeutic approaches for advanced PSCC.

Humans↗

PubMed1992

Gamma-interferon enhances the cytotoxic activity of interleukin-2-induced peripheral blood lymphocyte (LAK) cells, tumor infiltrating lymphocytes (TIL), and effusion associated lymphocytes.

The effect of gamma-interferon (IFN-gamma) on the induction of interleukin-2 (IL-2) activated killer cell activity was studied: (I) in peripheral blood lymphocytes (LAK cells) from cancer patients and healthy donors, (II) in lymphocytes infiltrating solid tumors (TIL) from melanoma and breast cancer patients, and (III) in pleural effusion associated lymphocytes (EAL) from patients with lung adenocarcinoma. The coculture of LAK, TIL and pleural effusion mononuclear cells (MNC) with several doses of IFN-gamma (10, 50, 250, and 1250 U/ml) and a low dose of IL-2 (10 U/ml) for 5 days resulted in a synergistic effect on the cytotoxicity of these cells against several tumor cell lines. Furthermore there was a potentiation in the proliferation of MNC after a 5-day culture. The induction of lymphocyte cytotoxicity by a combination of IFN-gamma with low doses of IL-2 may be helpful in designing more effective cancer immunotherapeutic protocols with LAK, TIL or EAL.

Cytotoxicity, Immunologic↗

PubMed2026

PSMA1, PSMA5, and PSMB2 serve as prognostic biomarkers and are correlated with tumor-infiltrating leukocytes in HCC.

Hepatocellular carcinoma (HCC) ranks as the third leading cause of cancer-related death. Proteasome (PSM) is the main intracellular proteolytic system in higher eukaryotic cells. It has been reported to be involved in the tumor's onset, metabolism, and survival, and it has been recognized as a therapeutic target for many human cancers. The 20S proteasome subunits, specifically proteasome 20S subunit alpha 1 (PSMA1), proteasome 20S subunit alpha 5 (PSMA5), and proteasome 20S subunit beta 2 (PSMB2), are overexpressed in various malignancies, including HCC. Nevertheless, the exact role of these genes in HCC prognosis remains only partially understood. Moreover, a reliable predictive biomarker for HCC is essential for supporting the implementation of personalized therapies. Therefore, this study employed a comprehensive bioinformatics approach, integrating data from cBioPortal, Human Protein Atlas (HPA), Oncomine, STRING Viruses, Kaplan-Meier plotter, and other established high-throughput databases and tools. The current study thoroughly examined the expression levels, methylation, and genomic alterations of PSM and their correlation with tumor-infiltrating leukocytes. PSMA1, PSMA5, and PSMB2 are overexpressed in various cancers, including HCC, and their expression levels are associated with tumor grade and stage. The abundance of these genes is linked to diminished DNA methylation levels and genome alterations. Moreover, there was a significant association between the expression levels of these genes and poor prognosis and immune cell infiltration. In conclusion, this study proposes PSMA1, PSMA5, and PSMB2 as biomarkers for HCC.

Humans↗

PubMed2026

Profiling tumor immune microenvironment of epithelial ovarian carcinoma.

BACKGROUND: Epithelial ovarian carcinoma (EOC) comprises five main histological subtypes: high-grade serous (HGSOC), low-grade serous (LGSOC), clear cell (CCOC), mucinous (MOC), and endometrioid (ENOC). Each histotype harbors specific genomic alterations and clinical outcome. Few studies systematically compared the tumor immune microenvironment across the five subtypes. METHODS: We performed 7-plex (CD45, CD8, CD68, CD163, FoxP3, CD20, and cytokeratin) sequential immunohistochemistry on a clinically annotated tissue microarray including 139 EOC representing the five subtypes and 26 borderline tumors (serous and mucinous). Digital pathology was used to quantify immune cell abundance, their spatial distribution (stroma vs tumor core), and correlation with survival. RESULTS: Immune cells were dominated by macrophages and more abundant in the stroma than tumor core across the five subtypes, consistent with immune excluded pattern. Compared to HGSOC, CCOC displayed the highest infiltration by CD45+ leukocytes and CD68+ macrophages, particularly M2-like CD163+ cells, suggesting a macrophage-rich, immunosuppressive phenotype. LGSOC exhibited the highest infiltration by intraepithelial FoxP3+ regulatory T cells. Comparison of borderline tumors with invasive carcinoma (LGOSC and MOC) revealed that malignant progression is accompanied by loss of CD8+ T cells, enrichment in regulatory T cells and increase of CD163+/CD68+ ratio, consistent with immune evasion during tumorigenesis. There was a trend toward better survival in HGSOC highly infiltrated by lymphocytes, either intraepithelial (CD8+ and FoxP3+) or stromal (FoxP3+ and CD20+). CONCLUSIONS: EOC is characterized by histotype-specific immune milieux defined by macrophage dominance, epithelial immune exclusion and dynamic immune remodeling during progression from borderline tumors to invasive carcinomas.

Humans↗

PubMed2026

Tumour-infiltrating lymphocytes differ across MammaPrint® classifications in breast cancer.

MammaPrint® refines risk stratification in early oestrogen receptor-positive, HER2-negative breast cancer, evolving from a binary to a four-tier classification (UltraLow-Risk, Low-Risk, High-Risk 1, and High-Risk 2). The relationship between routine histopathological features, immune infiltration, and genomic risk within this framework remains incompletely characterized in luminal disease. We retrospectively analysed 492 luminal breast carcinomas with available MammaPrint® results. Clinicopathological variables (including histological subtype, grade, Ki-67, hormone receptor expression, lymphovascular invasion (LVI), and HER2-low status) were recorded. Stromal tumour-infiltrating lymphocytes (TILs) were quantified according to the criteria of Salgado et al. and spatially categorized as immune-deserted, stromal-restricted, immune-excluded, or inflamed patterns. CD4 and CD8 infiltration was assessed by immunohistochemistry on tissue microarrays. Associations with binary and four-tier MammaPrint® categories were examined using multivariable models. High-Risk tumours (41%) were enriched for increased grade, Ki-67, and LVI and lower PR expression. In High-Risk tumours, inflamed spatial patterns were more frequent and median TIL levels were significantly higher compared with Low-Risk tumours (15% vs 5%, P < 0.001). CD4 and CD8 infiltration increased with genomic risk, and CD4 retained a modest but statistically significant association after adjustment for conventional pathological variables. In the four-tier model, UltraLow-Risk/Low-Risk tumours showed minimal TILs and were enriched for invasive lobular carcinoma, whereas High-Risk 1/High-Risk 2 tumours displayed progressively higher proliferative and immune features. No association was observed between HER2-low status and genomic risk. Immune infiltration parallels proliferative and genomic risk gradients in luminal breast cancer. These findings indicate that immune descriptors align with the genomic risk continuum, although their independent prognostic contribution beyond established genomic assays requires further evaluation.

Humans↗

PubMed2024

A comprehensive meta-analysis of tissue resident memory T cells and their roles in shaping immune microenvironment and patient prognosis in non-small cell lung cancer.

Tissue-resident memory T cells (TRM) are a specialized subset of long-lived memory T cells that reside in peripheral tissues. However, the impact of TRM-related immunosurveillance on the tumor-immune microenvironment (TIME) and tumor progression across various non-small-cell lung cancer (NSCLC) patient populations is yet to be elucidated. Our comprehensive analysis of multiple independent single-cell and bulk RNA-seq datasets of patient NSCLC samples generated reliable, unique TRM signatures, through which we inferred the abundance of TRM in NSCLC. We discovered that TRM abundance is consistently positively correlated with CD4+ T helper 1 cells, M1 macrophages, and resting dendritic cells in the TIME. In addition, TRM signatures are strongly associated with immune checkpoint and stimulatory genes and the prognosis of NSCLC patients. A TRM-based machine learning model to predict patient survival was validated and an 18-gene risk score was further developed to effectively stratify patients into low-risk and high-risk categories, wherein patients with high-risk scores had significantly lower overall survival than patients with low-risk. The prognostic value of the risk score was independently validated by the Cancer Genome Atlas Program (TCGA) dataset and multiple independent NSCLC patient datasets. Notably, low-risk NSCLC patients with higher TRM infiltration exhibited enhanced T-cell immunity, nature killer cell activation, and other TIME immune responses related pathways, indicating a more active immune profile benefitting from immunotherapy. However, the TRM signature revealed low TRM abundance and a lack of prognostic association among lung squamous cell carcinoma patients in contrast to adenocarcinoma, indicating that the two NSCLC subtypes are driven by distinct TIMEs. Altogether, this study provides valuable insights into the complex interactions between TRM and TIME and their impact on NSCLC patient prognosis. The development of a simplified 18-gene risk score provides a practical prognostic marker for risk stratification.

Humans↗

PubMed1992

[Malignant lymphomas of soft tissues].

Among annually 1000 consultation cases of soft tissue tumors, minimally 1.2% to maximally 2% malignant lymphomas could be identified, which presented as (primary) soft tissues tumor. Thus malignant lymphoma as soft tissue tumor is rare, however, it has to be considered in differential diagnosis not only of cellular round cell sarcoma, but also with undifferentiated carcinomas (large cell Ki-1 lymphomas) and various myxoid spindle cell sarcomas (sarcomatoid lymphoma). Decisive in differential diagnosis were decorations with pan-leucocyte antibody, as well as, B- and T-cell markers. All cases turned out to be non-Hodgkin lymphomas, the majority of B-cell type, with large cells which qualified as centroblasts (according to Kiel classification). Similar findings, predominance of B-cell non-Hodgkin lymphomas with large cells, were reported in the few series published of malignant lymphomas as soft tissue tumors. Remarkable were relatively good prognosis with "highly malignant" morphology and preference for involvement of soft tissue even after dissemination. Future studies are requested to shed light on possible specific cellular findings as to phenotype and genotype in malignant lymphoma presenting as soft tissue tumors, as already had been done with subcutaneous T-cell lymphoma and primary lymphoma of the bone.

Female↗

PubMed1992

[Demonstration of Epstein-Barr virus DNA and determination of immunoglobulin and T-cell receptor gene rearrangerments in diagnostic lymph node biopsies from patients with Hodgkin's disease].

Lymph node biopsies of 52 patients with Hodgkin's disease were analyzed by Southern blot hybridization for the presence of monoclonal rearrangements of immunoglobulin and T cell receptor genes. The same tissues were tested for Epstein-Barr virus DNA by the polymerase chain reaction using four different sets of primers. Monoclonal rearrangements were identified in only four tumors, whereas Epstein-Barr virus was present in 79% of biopsies. A correlation between the degree of infiltration by Reed-Sterberg cells, clonality and the presence of Epstein-Barr virus could not be found. These results are in agreement with similar studies reported in the literature. The nature of the malignant cell in Hodgkin's disease and the role of Epstein-Barr virus in the etiology of this tumor remains to be established.

Base Sequence↗

PubMed1992

[Hodgkin's disease--an entity?].

Since 26 years Hodgkins disease is classified according to the Rye classification into 4 types. This classification is based on morphology and has turned out to be clinically relevant. However, sometimes the classification on morphological and immunohistochemical ground can be difficult to put a special case in a defined category of the 4 types. In addition, there seems to be no sharp, or well defined borders between Hodgkin's disease and Non-Hodgkin's lymphomas, especially T-cell lymphomas. Immunophenotyping of small lymphocytes and detection of follicular dendritic cells can demonstrate typical patterns in different types of Hodgkin's disease. In all types of Hodgkin's disease there is the same amount of proliferating small T-cells present. Hodgkin cells are lymphoid cells with B- or T-cell markers. Hodgkin cells of nodular para-granuloma (lymphocyte predominant type of Hodgkin's disease) show m-RNA for one light chain in the cytoplasm which can be visualized by in situ-hybridization. A new technique called "molecular histology" is applied to Hodgkin's disease. This is a single cell PCR of immunostained cells extracted from tissue sections by a micromanipulator. This technique enables us for the first time to demonstrate light chain and heavy chain gene rearrangements in Hodgkin cells of nodular sclerosis and mixed cellularity type. Hodgkin's disease seems to be no single entity but a heterogenous group of B- and possibly T-cell lymphomas. In the B-cell types Hodgkin cells are probably pre-B and B-cells.

Chromosomes, Human, Pair 14↗

PubMed1992

[Autoimmune diseases and malignant lymphoma].

During the recent decade evidence accumulated, that autoantibodies exist with a high frequency in the normal B-cell repertoire. The autoreactive B-cell repertoire may undergo malignant transformation through the continuous challenge by autoantigen. Previous work on human paraproteins of plasmocytoma and immunocytoma has shown that a high proportion of paraproteins bind to self determinants. B-cell lymphoma may mimic the lesions in organotropic autoimmune disease, eg. Sjögren's disease, Hashimoto's thyroiditis and coeliac disease by the neoplastic expansion of autoimmune receptors. Considerable evidence has been obtained, that the specific receptor interactions of the lymphoma with the autoantigen may be of functional significance. More precise knowledge on receptor specificities would permit new approaches to the understanding and manipulation of autoimmune disease and lymphoma.

Autoantigens↗

PubMed1979

Functional activity of human tumor-infiltrating macrophages.

Explore the source record for details and available documents.

Breast Neoplasms↗

PubMed2026

MIF-CD74 axis facilitates MDSC infiltration in the tumor microenvironment of pancreatic ductal adenocarcinoma.

Immune checkpoint inhibitors show insufficient efficacy against pancreatic ductal adenocarcinoma (PDAC). The tumor microenvironment (TME) has a remarkable influence on responsiveness to cancer immunotherapy. The aim of this study was to investigate immunosuppressive characteristics of TME in PDAC tissues. The flow cytometry (FCM) of PDAC surgical specimens revealed that the profile of tumor-infiltrating leukocytes was classified into myeloid cell- and T-cell-dominant subtypes; the myeloid subtype was associated with poorer patient outcomes. Myeloid-derived suppressor cells (MDSCs) showed the highest hazard ratio among various myeloid cell types. Single-cell RNA sequencing and FCM revealed that most MDSCs, but not lymphocytes, in PDAC tissues characteristically express CD74. Macrophage migration inhibitory factor (MIF), a CD74 ligand, was highly expressed in cancer-associated fibroblasts (CAFs) and cancer cells. Spatial transcriptomics demonstrated that the MIF-CD74+ myeloid cell interaction was recognized in CAF-dominant areas in PDAC tissue. CAFs expressing immune suppressor molecules such as MFAP5 and LRRC15 were consistent with MIF+ CAFs. Furthermore, MIF+ CAFs enhanced the migratory activity of MDSCs and promoted MDSC induction and activation. In the murine model, MDSCs were significantly increased in MIF-expressing PDAC tumors, as were CD74+ M-MDSCs per M-MDSC, confirming in vivo interaction between CD74 and MIF. MDSCs play a crucial role in creating an immunosuppressive TME in PDAC; the MIF-CD74 axis drives interactions between MDSCs and CAFs.

Humans↗

PubMed2026

In vivo genome-wide CRISPR screens identify FOXR1 as a suppressor of CD8+ T cell antitumor immunity.

T cell dysfunction critically limits the efficacy of T cell-based immunotherapies in solid tumors, yet the intrinsic regulators of T cell dysfunction remain incompletely understood. Through an in vivo genome-wide CRISPR screen in tumor-infiltrating CD8+ T cells, we identified Forkhead Box R1 (FOXR1) as a potent transcriptional suppressor of CD8+ T cell effector functions. Genetic ablation of FOXR1 significantly enhanced cytokine production and cytotoxic capacity in both murine and human CD8+ T cells, whereas its overexpression impaired T cell activation and effector molecule expression. Mechanistically, multiomics integration of RNA-seq, CUT&Tag-seq, and ATAC-seq revealed that FOXR1 binds directly to promoter regions of key effector genes, including IL2, GZMB, and PRF1, and represses their expression. Importantly, FOXR1 deletion in human anti-CD19 CAR T cells improved their efficacy against solid tumors, demonstrating that FOXR1 is a checkpoint of T cell effector function and targeting FOXR1 is a promising strategy to enhance CAR T cell efficacy against solid tumors.

Animals↗

PubMed2026

A Phase II Feasibility Study Combining Pembrolizumab and Metformin in Patients with Metastatic Head and Neck Cancer.

PURPOSE: Survival for recurrent/metastatic head and neck squamous cell carcinoma (R/M HNSCC) remains low with <20% immunotherapy response. Metformin increases tumor-infiltrating CD8+ T and natural killer (NK) cells, which harbor PD-1. In this phase II clinical trial (NCT04414540), we combined metformin and pembrolizumab to evaluate the overall response rate (ORR) in R/M HNSCC and assess NK-cell activity. PATIENTS AND METHODS: Eligible patients were randomized 1:1 into two arms: (i) metformin extended-release (ER) dose escalation to 2,000 mg over 14 days followed by combination with pembrolizumab 200 mg every 3 weeks or (ii) pembrolizumab 200 mg every 3 weeks followed by combination with metformin ER 2,000 mg daily. The primary endpoint was ORR per RECIST 1.1. Nineteen evaluable patients were planned to estimate the proportion of approximately 32% ORR. Safety was evaluated according to Common Terminology Criteria for Adverse Events v5.0. The distribution, activation, and cytotoxic function of NK cells were analyzed via flow cytometry. RESULTS: Twenty-one patients were enrolled; 76% were male, 52% were smokers, and the median age was 64 years. Ten patients had oropharyngeal tumors, of which nine were p16+. Eighteen patients were evaluable for response, including four complete and five partial responses for an ORR of 50% [95% confidence interval (29-71)]. Combination therapy was well tolerated with no unexpected adverse events (AE). Five grade 3 AEs occurred: nausea, diarrhea, fatigue, and weight loss. Metformin led to increased peripheral NK-cell maturation and cytotoxic ability. CONCLUSIONS: The combination of metformin and pembrolizumab was well tolerated with mild gastrointestinal AEs and promising activity, warranting further investigation in a randomized trial.

Humans↗