Cancer cell-expressed BTNL2 facilitates tumour immune escape via engagement with IL-17A-producing γδ T cells

Progress of research on γδ T cells in colorectal cancer (Review)

Colorectal cancer (CRC) ranks as the third most prevalent malignancy and second leading cause of cancer‑related fatalities worldwide. Immunotherapy alone or in combination with chemotherapy has a favorable survival benefit for patients with CRC. Unlike αβ T cells, which are prone to drug resistance, γδ T cells do not exhibit major histocompatibility complex restriction and can target tumor cells through diverse mechanisms. Recent research has demonstrated the widespread involvement of Vδ1T, Vδ2T, and γδ T17 cells in tumorigenesis and progression. In the present review, the influence of different factors, including immune checkpoint molecules, the tumor microenvironment and microorganisms, was summarized on the antitumor/protumor effects of these cells, aiming to provide insights for the development of more efficient and less toxic immunotherapy‑based anticancer drugs.

PD-1 regulation of pathogenic IL-17-secreting γδ T cells in experimental autoimmune encephalomyelitis

The PD-1-PD-L1 immune checkpoint helps to maintain self-tolerance and prevent the development of autoimmune diseases. Immune checkpoint inhibitors are successful immunotherapeutics for several cancers, but responding patients can develop immune-mediated adverse events. It is well established that PD-1 regulates CD4 and CD8 T-cell responses, but its role in controlling the activation of pathogenic γδ T cells is less clear. Here we examined the role of PD-1 in regulating γδ T cells in experimental autoimmune encephalomyelitis (EAE), a mouse model of multiple sclerosis. We found that PD-1 was highly expressed on CD27- Vγ4 γδ T cells in the lymph node (LN) and CNS of mice with EAE. Treatment of mice with anti-PD-1 significantly augmented IL-17A-producing CD27- Vγ4 γδ T cells in the LN and CNS and enhanced the severity of EAE. The exacerbating effect of anti-PD-1 on EAE was lost in Tcrd-/- mice. Conversely, ligation of PD-1 suppressed Il17a and Rorc gene expression and IL-17A production by purified Vγ4 γδ T cells stimulated via the TCR, but not with IL-1β and IL-23. Our study demonstrates that PD-1 regulates TCR-activated CD27- Vγ4 γδ T cells, but that cytokine-activated IL-17A producing γδ T cells escape the regulatory effects of the PD-1-PD-L1 pathway.

Pan-cancer exploration of PNO1: A prospective prognostic biomarker with ties to immune infiltration

The partner of NOB1 homolog (PNO1) is an RNA-binding protein that participates in ribosome biogenesis and protein modification. The functions of this molecule are largely unknown in cancers, particularly breast cancer. We employed bioinformatics methods to probe the putative oncogenic functions of PNO1 based on expression profiles and clinical data from the cancer genome atlas (TCGA), genotype-tissue expression project (GTEx), human protein atlas (HPA), cancer cell line encyclopedia (CCLE), UALCAN, drug sensitivity in cancer (GDSC) and UCSC XENA databases. Our analyses revealed that PNO1 was overexpressed in 31 malignancies, which excluded kidney chromophobe (KICH) and acute myeloid leukemia (LAML). Prognostic assessments have demonstrated that high PNO1 expression was significantly correlated with poor overall and disease-specific survival in various cancers. The promoter methylation level of PNO1 is significantly decreased in breast invasive carcinoma (BRCA), head and neck squamous cell carcinoma (HNSC), kidney renal papillary cell carcinoma (KIRP), prostate adenocarcinoma (PRAD), thyroid carcinoma (THCA) and uterine corpus endometrial carcinoma (UCEC). Furthermore, inhibition of PNO1 decreased the viability, migration and invasion of breast cancer cells, and these results were confirmed by mouse xenograft models of breast cancer. In addition, we discovered that tumor microenvironment (TME), immune infiltration, and chemotherapy sensitivity were influenced by PNO1 expression. Concordantly, our analyses revealed a significant positive correlation between PNO1 and programmed cell death ligand 1 (PD-L1) expression across breast carcinoma samples. In conclusion, these findings indicate that PNO1 could act as a promising prognostic biomarker and adjunct diagnostic indicator, because it affects tumor growth and invasion. Our study offers valuable new perspectives on the oncogenic role of PNO1 in various types of cancers.

Dendritic Cell-Hitchhiking In Vivo for Vaccine Delivery to Lymph Nodes

Therapeutic cancer vaccines are among the first FDA-approved cancer immunotherapies. Among them, it remains a major challenge to achieve robust lymph-node (LN) accumulation. However, delivering cargo into LN is difficult owing to the unique structure of the lymphatics, and clinical responses have been largely disappointing. Herein, inspired by the Migrated-DCs homing from the periphery to the LNs, an injectable hydrogel-based polypeptide vaccine system is described for enhancing immunostimulatory efficacy, which could form a local niche of vaccine "hitchhiking" on DCs. The OVA peptide modified by lipophilic DSPE domains in the hydrogel is spontaneously inserted into the cell membrane to achieve "antigen anchoring" on DCs in vivo. Overall, OVA peptide achieves active access LNs through recruiting and "hitchhiking" subcutaneous Migrated-DCs. Remarkably, it is demonstrated that the composite hydrogel enhances LNs targeting efficacy by approximately six-fold compared to free OVA peptide. Then, OVA peptide can be removed from the cell surface under a typical acidic microenvironment within the LNs, further share them with LN-resident APCs via the "One-to-Many" strategy (One Migrated-DC corresponding to Many LN-resident APCs), thereby activating powerful immune stimulation. Moreover, the hydrogel vaccine exhibits significant tumor growth inhibition in melanoma and inhibits pulmonary metastatic nodule formation.

Pro- and antitumorigenic functions of γδ T cells

γδ T cells are a subset of T cells that are characterized by the expression of a TCR-γδ instead of a TCR-αβ. Despite being outnumbered by their αβ T cell counterpart in many tissues, studies from the last 20 years underline their important and non-redundant roles in tumor and metastasis development. However, whether a γδ T cell exerts pro- or antitumorigenic effects seems to depend on a variety of factors, many of them still incompletely understood today. In this review, we summarize mechanisms by which γδ T cells exert these seemingly contradictory effector functions in mice and humans. Furthermore, we discuss the current view on inducing and inhibiting factors of γδ T cells during cancer development.

The use of peripheral CD3+γδ+Vδ2+ T lymphocyte cells in combination with the ALBI score to predict immunotherapy response in patients with advanced hepatocellular carcinoma: a retrospective study

BACKGROUND

Currently, there is a lack of effective indicators for predicting the efficacy of immunotherapy in patients with advanced hepatocellular carcinoma (HCC). This study aimed to investigate the expression and prognostic value of peripheral T lymphocyte subsets in advanced HCC.

METHODS

Patients with advanced HCC who were treated with immune checkpoint inhibitors (ICIs) from December 2021 to December 2023 were included in the study. Flow cytometry was used to detect lymphocyte subsets before treatment. The patients were divided into disease control (DC) and nondisease control (nDC) groups based on treatment efficacy. Relationships between the clinical characteristics/peripheral T lymphocytes and immunotherapy efficacy were analyzed. The effectiveness of peripheral T lymphocyte subsets in predicting immunotherapy efficacy for patients with advanced HCC was analyzed using receiver operating characteristic (ROC) curves.

RESULTS

A total of 40 eligible patients were included in this study. Non-DC was significantly associated with higher albumin-bilirubin (ALBI) scores. The percentages of γδ+Vδ2+PD1+ T cells and γδ+Vδ2+Tim3+ T cells were greater in the nDC group than in the DC group. Multivariable regression analysis revealed that the ALBI score and T lymphocytes expressing γδ+Vδ2+PD1+ and γδ+Vδ2+Tim3+ were founded to be independent influencing factors. The area under the ROC curve (AUC) values for these combinations was 0.944 (95% CI, 0.882 ~ 1.000).

CONCLUSIONS

The calculation of the ALBI score and determination of the percentages CD3+γδ+Vδ2+PD1+ T lymphocytes and CD3+γδ+Vδ2+Tim3+ T lymphocytes in the peripheral blood of patients with advanced HCC are helpful for predicting the patients' responses to ICIs, helping to screen patients who may clinically benefit from immunotherapy. RETROSPECTIVELY REGISTERED: number: ChiCTR2400080409, date of registration: 2024-01-29.

A Ménage à trois: NLRC5, immunity, and metabolism

The nucleotide-binding and oligomerization domain-like receptors (NLRs) NLR family CARD domain-containing protein 5 (NLRC5) and Class II Major Histocompatibility Complex Transactivator (CIITA) are transcriptional regulators of major histocompatibility complex (MHC) class I and class II genes, respectively. MHC molecules are central players in our immune system, allowing the detection of hazardous 'non-self' antigens and, thus, the recognition and elimination of infected or transformed cells from the organism. Recently, CIITA and NLRC5 have emerged as regulators of selected genes of the butyrophilin (BTN) family that interestingly are located in the extended MHC locus. BTNs are transmembrane proteins exhibiting structural similarities to B7 family co-modulatory molecules. The family member BTN2A2, which indeed contributes to the control of T cell activation, was found to be transcriptionally regulated by CIITA. NLRC5 emerged instead as an important regulator of the BTN3A1, BTN3A2, and BTN3A3 genes. Together with BTN2A1, BTN3As regulate non-conventional Vγ9Vδ2 T cell responses triggered by selected metabolites of microbial origin or accumulating in hematologic cancer cells. Even if endogenous metabolites conform to the canonical definition of 'self', metabolically abnormal cells can represent a danger for the organism and should be recognized and controlled by immune system cells. Collectively, new data on the role of NLRC5 in the expression of BTN3As link the mechanisms regulating canonical 'non-self' presentation and those marking cells with abnormal metabolic configurations for immune recognition, an evolutionary parallel that we discuss in this perspective review.

Shared genetic factors and causal association between chronic hepatitis C infection and diffuse large B cell lymphoma

BACKGROUND

Epidemiological research and systematic meta-analyses indicate a higher risk of B-cell lymphomas in patients with chronic hepatitis C virus (HCV) compared to non-infected individuals. However, the genetic links between HCV and these lymphomas remain under-researched.

METHODS

Mendelian randomization analysis was employed to explore the association between chronic hepatitis C (CHC) and B-cell lymphomas as well as chronic lymphocytic leukemia (CLL). Approximate Bayes Factor (ABF) localization analysis was conducted to find shared genetic variants that might connect CHC with B-cell lymphomas and chronic lymphocytic leukemia (CLL). Furthermore, The Variant Effect Predictor (VEP) was utilized to annotate the functional effects of the identified genetic variants.

RESULTS

Mendelian randomization revealed a significant association between CHC and increased diffuse large B cell lymphoma (DLBCL) risk (OR: 1.34; 95% CI: 1.01-1.78; P = 0.0397). Subsequent colocalization analysis pinpointed two noteworthy variants, rs17208853 (chr6:32408583) and rs482759 (chr6:32227240) between these two traits. The annotation of these variants through the VEP revealed their respective associations with the butyrophilin-like protein 2 (BTNL2) and notch receptor 4 (NOTCH4) genes, along with the long non-coding RNA (lncRNA) TSBP1-AS1.

CONCLUSION

This research provides a refined genetic understanding of the CHC-DLBCL connection, opening avenues for targeted therapeutic research and intervention.

The B7:CD28 family and friends: Unraveling coinhibitory interactions

Immune responses must be tightly regulated to ensure both optimal protective immunity and tolerance. Costimulatory pathways within the B7:CD28 family provide essential signals for optimal T cell activation and clonal expansion. They provide crucial inhibitory signals that maintain immune homeostasis, control resolution of inflammation, regulate host defense, and promote tolerance to prevent autoimmunity. Tumors and chronic pathogens can exploit these pathways to evade eradication by the immune system. Advances in understanding B7:CD28 pathways have ushered in a new era of immunotherapy with effective drugs to treat cancer, autoimmune diseases, infectious diseases, and transplant rejection. Here, we discuss current understanding of the mechanisms underlying the coinhibitory functions of CTLA-4, PD-1, PD-L1:B7-1 and PD-L2:RGMb interactions and less studied B7 family members, including HHLA2, VISTA, BTNL2, and BTN3A1, as well as their overlapping and unique roles in regulating immune responses, and the therapeutic potential of these insights.

N-terminal ectodomain of BTNL2 inhibits T cell activation via a non-canonical interaction with its putative receptor that results in a delayed progression of DSS-induced ulcerative colitis

Butyrophilin-like 2 (BTNL2) is a T cell inhibitory molecule that interacts with unknown binding partners to modulate the immune response in a number of inflammatory and autoimmune diseases. In this study, we found that the inhibitory effects of BTNL2 on T cell activation and effector functions can be executed by its N-terminal IgV domain (BTNL2 IgV1) alone. Structure-guided mutation of key residues on BTNL2 IgV1 based on known receptor-ligand interfaces involving immunoglobulin superfamily members revealed that BTNL2 uses a non-canonical binding interface with its putative receptor. A high avidity BTNL2 IgV1 probe revealed that in an inducible model of ulcerative colitis, severe colitis was accompanied by a selective enrichment of BTNL2-receptor expressing effector-memory CD4+ and CD8+ T cells in the Peyer's patches. Intraperitoneal administration of BTNL2 IgV1 resulted in a significant delay in the progression of DSS-induced colitis and also showed reduced activation of the BTNL2-receptor-expressing T cells in the Peyer's patches. Thus, this study demonstrates that the BTNL2-receptor-expressing T cells in the Peyer's patches participate in the disease pathogenesis and can serve as a novel therapeutic target in ulcerative colitis, which can be modulated by BTNL2 IgV1.

γδ T cells: Major advances in basic and clinical research in tumor immunotherapy

ABSTRACT

γδ T cells are a kind of innate immune T cell. They have not attracted sufficient attention because they account for only a small proportion of all immune cells, and many basic factors related to these cells remain unclear. However, in recent years, with the rapid development of tumor immunotherapy, γδ T cells have attracted increasing attention because of their ability to exert cytotoxic effects on most tumor cells without major histocompatibility complex (MHC) restriction. An increasing number of basic studies have focused on the development, antigen recognition, activation, and antitumor immune response of γδ T cells. Additionally, γδ T cell-based immunotherapeutic strategies are being developed, and the number of clinical trials investigating such strategies is increasing. This review mainly summarizes the progress of basic research and the clinical application of γδ T cells in tumor immunotherapy to provide a theoretical basis for further the development of γδ T cell-based strategies in the future.

Interleukin-17A Promotes Proliferation and Osteogenic Differentiation of Human Ligamentum Flavum Cells Through Regulation of β-Catenin Signaling

STUDY DESIGN

A basic experimental study.

OBJECTIVE

To elucidate the role and mechanism of interleukin (IL)-17A in thoracic ossification of the ligamentum flavum (TOLF).

SUMMARY OF BACKGROUND DATA

TOLF is characterized by the replacement of the thoracic ligamentum flavum with ossified tissue and is one of the leading causes of thoracic spinal stenosis. IL-17A is an important member of the IL-17 family that has received widespread attention for its key contributions to the regulation of bone metabolism and heterotopic ossification. However, it is unclear whether IL-17A is involved in TOLF.

MATERIALS AND METHODS

Cell counting kit-8 assay and 5-ethynyl-2'-deoxyuridine staining were performed to assess the proliferation of ligamentum flavum cells (LFCs). Alkaline phosphatase activity assay, Alizarin red staining, and protein level expression of osteogenic-related genes were used to evaluate the osteogenic differentiation potential of LFCs. The effect of IL-17A on the proliferation and osteogenic differentiation of LFCs was further assessed after silencing β-catenin by transfection with small interfering RNA. In addition, the possible source of IL-17A was further demonstrated by coculture assays of T helper 17 (Th17) cells with LFCs. Student t test was used for comparisons between groups, and the one-way analysis of variance, followed by the Tukey post hoc test, was used for comparison of more than two groups.

RESULTS

IL-17A was elevated in TOLF tissue compared with normal ligamentum flavum. IL-17A stimulation promoted the proliferation and osteogenic differentiation of LFCs derived from patients with TOLF. We found that IL-17A promoted the proliferation and osteogenic differentiation of LFCs by regulating the β-catenin signaling. Coculture of Th17 cells with LFCs enhanced β-catenin signaling-mediated proliferation and osteogenic differentiation of LFCs. However, these effects were markedly attenuated after the neutralization of IL-17A.

CONCLUSIONS

This is the first work we are aware of to highlight the importance of IL-17A in TOLF. IL-17A secreted by Th17 cells in the ligamentum flavum may be involved in the ossification of the microenvironment by regulating β-catenin signaling to promote the proliferation and osteogenic differentiation of LFCs.

Butyrophilins: Dynamic Regulators of Protective T Cell Immunity in Cancer

The efficacy of current immunotherapies remains limited in many solid epithelial malignancies. Recent investigations into the biology of butyrophilin (BTN) and butyrophilin-like (BTNL) molecules, however, suggest these molecules are potent immunosuppressors of antigen-specific protective T cell activity in tumor beds. BTN and BTNL molecules also associate with each other dynamically on cellular surfaces in specific contexts, which modulates their biology. At least in the case of BTN3A1, this dynamism drives the immunosuppression of αβ T cells or the activation of Vγ9Vδ2 T cells. Clearly, there is much to learn regarding the biology of BTN and BTNL molecules in the context of cancer, where they may represent intriguing immunotherapeutic targets that could potentially synergize with the current class of immune modulators in cancer. Here, we discuss our current understanding of BTN and BTNL biology, with a particular focus on BTN3A1, and potential therapeutic implications for cancer.

BTNL2 promotes colitis-associated tumorigenesis in mice by regulating IL-22 production

Interleukin 22 (IL-22) has an important role in colorectal tumorigenesis and many colorectal diseases such as inflammatory bowel disease and certain infections. However, the regulation of IL-22 production in the intestinal system is still unclear. Here, we present evidence that butyrophilin-like protein 2 (BTNL2) is required for colorectal IL-22 production, and BTNL2 knockout mice show decreased colonic tumorigenesis and more severe colitis phenotypes than control mice due to defective production of IL-22. Mechanistically, BTNL2 acts on group 3 innate lymphoid cells (ILC3s), CD4+ T cells, and γδ T cells to promote the production of IL-22. Importantly, we find that a monoclonal antibody against BTNL2 attenuates colorectal tumorigenesis in mice and that the mBTNL2-Fc recombinant protein has a therapeutic effect in a dextran sulfate sodium (DSS)-induced colitis model. This study not only identifies a regulatory mechanism of IL-22 production in the colorectal system but also provides a potential therapeutic target for the treatment of human colorectal cancer and inflammatory bowel diseases.

Gamma delta T-cell-based immune checkpoint therapy: attractive candidate for antitumor treatment

As a nontraditional T-cell subgroup, γδT cells have gained popularity in the field of immunotherapy in recent years. They have extraordinary antitumor potential and prospects for clinical application. Immune checkpoint inhibitors (ICIs), which are efficacious in tumor patients, have become pioneer drugs in the field of tumor immunotherapy since they were incorporated into clinical practice. In addition, γδT cells that have infiltrated into tumor tissues are found to be in a state of exhaustion or anergy, and there is upregulation of many immune checkpoints (ICs) on their surface, suggesting that γδT cells have a similar ability to respond to ICIs as traditional effector T cells. Studies have shown that targeting ICs can reverse the dysfunctional state of γδT cells in the tumor microenvironment (TME) and exert antitumor effects by improving γδT-cell proliferation and activation and enhancing cytotoxicity. Clarification of the functional state of γδT cells in the TME and the mechanisms underlying their interaction with ICs will solidify ICIs combined with γδT cells as a good treatment option.

Prognostic role of soluble PD-1 and BTN2A1 in overweight melanoma patients treated with nivolumab or pembrolizumab: finding the missing links in the symbiotic immune-metabolic interplay

Individual response to immune checkpoint inhibitors (ICIs) is currently unpredictable in patients with melanoma. Recent findings highlight a striking improvement in the clinical outcomes of overweight/obese patients treated with ICIs, which seems driven, at least in part, by programmed cell death protein 1 (PD-1)-mediated T-cell dysfunction. A putative role of butyrophilins (BTNs) is under investigation as a novel mechanism of cancer immune evasion and obesity-associated inflammation. This study investigates the role of baseline plasma levels of soluble PD-1 (sPD-1), soluble programmed cell death ligand 1 (sPD-L1), BTN2A1 (sBTN2A1), BTN3A1 (sBTN3A1), along with body mass index (BMI), as predictive biomarkers of immunotherapy response in metastatic melanoma patients treated with nivolumab or pembrolizumab as first-line treatment. In all, 41 patients were included in the study. The baseline plasma level of sPD-1 was significantly lower, and the sBTN2A1 was significantly higher, in long-responder patients to nivolumab or pembrolizumab (median sPD-1: 10.3 ng/ml versus 16.6 ng/ml, p = 0.001; median sBTN2A1: 4.4 ng/ml versus 3.77 ng/ml, p = 0.004). Lower levels of sPD-1 and higher levels of sBTN2A1 were also significantly associated with better overall response rate. Notably, when we further stratified the study cohort using BMI along with sPD-1, patients with BMI ⩾ 25 and sPD-1 < 11.24 ng/ml had longer time to treatment failure after PD-1 inhibitor than other subgroups of patients (p < 0.001). Circulating sPD-1 and sBTN2A1 detection, along with BMI, could give more insights into the immune-metabolic interactions underlying the benefit observed in overweight/obese patients, improving the use of dynamic, noninvasive, biomarkers for patient selection.

CAR γδ T cells for cancer immunotherapy. Is the field more yellow than green?

Engineered immune cell therapy to treat malignancies refractory to conventional therapies is modernizing oncology. Although αβ T cells are time-tested chassis for CAR, potential graft versus host disease (GvHD) apart from cytokine toxicity and antigen escape pose limitations to this approach. αβ T cell malignancy challenges isolation and expansion of therapeutic T cells. Moreover, αβ T cells may pose toxicity risk to inflammation sensitive vital tissues bearing the tumor. The HLA independent, multivalent, versatile and systemic anti-tumor immunity increases the desirability of γδ T cells as an alternate chassis for CAR. Indeed, CD19 γδ CAR T cell therapy to treat advanced lymphoma reached a milestone with the fast track status by FDA. However, reduced tumor-toxicity, homing, in vivo persistence and heterogeneity limits the translation of this therapy. The field is gaining momentum in recent years with optimization of gene delivery approaches and mechanistic insights into co-signaling requirements in γδ T cells. There is a renewed interest in customizing design of CAR guided by the biology of the host immune cells. Progress has been made in the current good manufacturing practice compatible expansion and engineering protocols for the δ1 and δ2 T cells. γδ CAR T cells may find its niche in the clinical situations wherein conventional CAR therapy is less suitable due to propensity for cytokine toxicity or off-tumor effect. As the therapy is moving towards clinical trials, this review chronicles the hitherto progress in the therapeutic engineering of γδ T cells for cancer immunotherapy.

Cuprotosis Programmed-Cell-Death-Related lncRNA Signature Predicts Prognosis and Immune Landscape in PAAD Patients

In terms of mortality and survival, pancreatic cancer is one of the worst malignancies. Known as a unique type of programmed cell death, cuprotosis contributes to tumor cell growth, angiogenesis, and metastasis. Cuprotosis programmed-cell-death-related lncRNAs (CRLs) have been linked to PAAD, although their functions in the tumor microenvironment and prognosis are not well understood. This study included data from the TCGA-PAAD cohort. Random sampling of PAAD data was conducted, splitting the data into two groups for use as a training set and test set (7:3). We searched for differentially expressed genes that were substantially linked to prognosis using univariate Cox and Lasso regression analysis. Through the use of multivariate Cox proportional risk regression, a risk-rating system for prognosis was developed. Correlations between the CRL signature and clinicopathological characteristics, tumor microenvironment, immunotherapy response, and chemotherapy sensitivity were further evaluated. Lastly, qRT-PCR was used to compare CRL expression in healthy tissues to that in tumors. Some CRLs are thought to have strong correlations with PAAD outcomes. These CRLs include AC005332.6, LINC02041, LINC00857, and AL117382.1. The CRL-based signature construction exhibited outstanding predictive performance and offers a fresh approach to evaluating pre-immune effectiveness, paving the way for future studies in precision immuno-oncology.

Prognosis analysis of necroptosis-related genes in colorectal cancer based on bioinformatic analysis

Background: Colorectal cancer (CRC) is one gastrointestinal malignancy, accounting for 10% of cancer diagnoses and cancer-related deaths worldwide each year. Therefore, it is urgent to identify genes involved in CRC predicting the prognosis.

Methods: CRC’s data were acquired from the Gene Expression Omnibus (GEO) database (GSE39582 and GSE41258 datasets) and The Cancer Genome Atlas (TCGA) database. The differentially expressed necroptosis-related genes (DENRGs) were sorted out between tumor and normal tissues. Univariate Cox regression analysis and least absolute shrinkage and selectionator operator (LASSO) analysis were applied to selected DENRGs concerning patients’ overall survival and to construct a prognostic biomarker. The effectiveness of this biomarker was assessed by the Kaplan–Meier curve and the receiver operating characteristic (ROC) analysis. The GSE39582 dataset was utilized as external validation for the prognostic signature. Moreover, using univariate and multivariate Cox regression analyses, independent prognostic factors were identified to construct a prognostic nomogram. Next, signaling pathways regulated by the signature were explored through the gene set enrichment analysis (GSEA). The single sample gene set enrichment analysis (ssGSEA) algorithm and tumor immune dysfunction and exclusion (TIDE) were used to explore immune correlation in the two groups, high-risk and low-risk ones. Finally, prognostic genes’ expression was examined in the GSE41258 dataset.

Results: In total, 27 DENRGs were filtered, and a necroptosis-related prognostic signature based on 6 DENRGs was constructed, which may better understand the overall survival (OS) of CRC. The Kaplan–Meier curve manifested the effectiveness of the prognostic signature, and the ROC curve showed the same result. In addition, univariate and multivariate Cox regression analyses revealed that age, pathology T, and risk score were independent prognostic factors, and a nomogram was established. Furthermore, the prognostic signature was most significantly associated with the apoptosis pathway. Meanwhile, 24 immune cells represented significant differences between two groups, like the activated B cell. Furthermore, 32 immune checkpoints, TIDE scores, PD-L1 scores, and T-cell exclusion scores were significantly different between the two groups. Finally, a 6-gene prognostic signature represented different expression levels between tumor and normal samples significantly in the GSE41258 dataset.

Conclusion: Our study established a signature including 6 genes and a prognostic nomogram that could significantly assess the prognosis of patients with CRC.

TCR-Vγδ usage distinguishes protumor from antitumor intestinal γδ T cell subsets

γδ T cells represent a substantial fraction of intestinal lymphocytes at homeostasis, but they also constitute a major lymphocyte population infiltrating colorectal cancers (CRCs); however, their temporal contribution to CRC development or progression remains unclear. Using human CRC samples and murine CRC models, we found that most γδ T cells in premalignant or nontumor colons exhibit cytotoxic markers, whereas tumor-infiltrating γδ T cells express a protumorigenic profile. These contrasting T cell profiles were associated with distinct T cell receptor (TCR)-Vγδ gene usage in both humans and mice. Longitudinal intersectional genetics and antibody-dependent strategies targeting murine γδ T cells enriched in the epithelium at steady state led to heightened tumor development, whereas targeting γδ subsets that accumulate during CRC resulted in reduced tumor growth. Our results uncover temporal pro- and antitumor roles for γδ T cell subsets.

Butyrophilins: γδ T Cell Receptor Ligands, Immunomodulators and More

Butyrophilins (BTN) are relatives of the B7 family (e.g., CD80, PD-L1). They fulfill a wide range of functions including immunomodulation and bind to various receptors such as the γδ T cell receptor (γδTCR) and small molecules. One intensively studied molecule is BTN3A1, which binds via its cytoplasmic B30.2 domain, metabolites of isoprenoid synthesis, designated as phosphoantigen (PAg), The enrichment of PAgs in tumors or infected cells is sensed by Vγ9Vδ2 T cells, leading to the proliferation and execution of effector functions to remove these cells. This article discusses the contribution of BTNs, the related BTNL molecules and SKINT1 to the development, activation, and homeostasis of γδ T cells and their immunomodulatory potential, which makes them interesting targets for therapeutic intervention.