CMTM6 shapes antitumor T cell response through modulating protein expression of CD58 and PD-L1

Dual Ribosome Profiling reveals metabolic limitations of cancer and stromal cells in the tumor microenvironment

The tumor microenvironment (TME) influences cancer cell metabolism and survival. However, how immune and stromal cells respond to metabolic stress in vivo, and how nutrient limitations affect therapy, remains poorly understood. Here, we introduce Dual Ribosome Profiling (DualRP) to simultaneously monitor translation and ribosome stalling in multiple tumor cell populations. DualRP reveals that cancer-fibroblast interactions trigger an inflammatory program that reduces amino acid shortages during glucose starvation. In immunocompetent mice, we show that serine and glycine are essential for optimal T cell function and that their deficiency impairs T cell fitness. Importantly, immune checkpoint blockade therapy imposes amino acid restrictions specifically in T cells, demonstrating that therapies create distinct metabolic demands across TME cell types. By mapping codon-resolved ribosome stalling in a cell‑type‑specific manner, DualRP uncovers metabolic crosstalk that shapes translational programs. DualRP thus offers a powerful, innovative approach for dissecting tumor cell metabolic interplay and guiding combined metabolic-immunotherapeutic strategies.

A potential prognostic marker for hematologic neoplasms: CD58

CD58 is a glycoprotein receptor widely distributed on histiocytes that binds to CD2, that takes part in constituting the Immunological Synapses (IS) and activating T/NK cells. Aberrant expression of CD58 has been demonstrated to exert a significant impact on the prognosis of hematological tumors, including leukemia and lymphoma. Furthermore, this aberrant expression has been associated with drug resistance and immune rejection in CAR cell therapy. In this article, we will explore the future of CD58 in hematological oncology by describing its function in immune cells, its impact on hematological oncology and immunotherapies such as CAR cell therapy.

CMTM3 Promotes Colitis-associated Carcinogenesis Via CLTC Stabilization and Modulation of VE-cadherin

BACKGROUND & AIMS

Inflammatory bowel disease leads to increased risk of developing colitis-associated colon cancer (CAC). CMTM3 has a higher methylation level in colon cancer, and accumulating evidence suggests that chemokine-like factor-like MARVEL transmembrane domain-containing member 3 (CMTM3) participates in inflammation and cancer development.

METHODS

We explored the signs of azoxymethane (AOM)/dextran sulfate sodium (DSS)-induced CAC in wild-type (WT) and Cmtm3 deficiency (Cmtm3-/-) mice. Experimental colitis was induced in Cmtm3-/- mice as well as mice with endothelial cell-specific deletion of Cmtm3. Disease phenotypes were investigated by body weight, disease activity index (DAI), colon length, histology, immune cell infiltration, and intestinal permeability. The mechanism was analyzed using bone marrow reconstitution, immunofluorescent staining, Western blot, immunoprecipitation, and pull-down experiments.

RESULTS

We found CMTM3 promoted CAC by aggravating colitis. Further, we revealed endothelial cell-specific deletion of Cmtm3 inhibited the colitis development. In vitro and in vivo mechanistic studies revealed that CMTM3 drove colitis by increasing clathrin-dependent downregulation of vascular endothelial-cadherin, thus causing vascular permeability. We further identified that CMTM3 interacted with clathrin heavy chain and inhibited clathrin heavy chain ubiquitination and proteasome-dependent degradation. Interestingly, Cmtm3 knockout and imatinib mesylate both targeted vascular permeability and had comparable efficacy.

CONCLUSIONS

Our study indicates that CMTM3 promotes CAC by aggravating colitis through causing vascular permeability, providing insights into targets for development of future therapies.

Comprehensive analysis of CMTM family and immune infiltration in esophageal carcinoma

OBJECTIVE

Esophageal carcinoma (ESCA) is one of the most common malignant diseases and contributes to the annual burden of death worldwide. A better understanding of the underlying molecular changes is urgently required to identify early diagnostic biomarkers and effective therapeutics. The chemokine-like factor (CKLF)-like MARVEL transmembrane domain-containing family (CMTMs) is reported to be entangled in many human cancers. However, the role of CMTMs in ESCA remains unclear.

METHODS

The differential expressions of CMTMs between ESCA and normal tissues were analyzed using TCGA database. The relationships between CMTMs and immune infiltration in the tumor microenvironment (TME) were also evaluated to explore their underlying values in the diagnosis and prognosis of ESCA.

RESULTS

The results showed that ESCA showed significantly higher expressions of CMTM1,3,6,7 and lower expressions of CMTM4,5 than normal tissue (P < 0.05). Meanwhile, CMTM3,4,8 expressions were correlated with the tumor stage of ECSA patients. The analysis on immune infiltrations (CD8 + T, Tregs, NK and macrophages) showed that M2 macrophages was dominant in TME, with significantly higher levels than the other cells (F = 326.93, P < 0.001). The higher abundance of M2 macrophages and Tregs significantly shortened the survival time of patients with ESCA (P = 0.01). Interestingly, the expression levels of CMTM1,3,5,7 were comparable to the abundance of M2 macrophages (CMTM1: r = 0.172168; CMTM3: r = 0.313221; CMTM5: r = 0.130669; CMTM7: r = 0.119922; P < 0.05). CMTM2,4,5,7,8 positively correlated with Tregs (P < 0.05). Moreover, we found positive associations between the expression of CMTMs and the signatures of M2 macrophages (MS4A4A, VSIG4 and CD163).

CONCLUSION

There were differential expressions of CMTMs between ESCA and normal tissues. Furthermore, the expression of CMTMs was positively correlated with M2 macrophages, indicating a possibility that CMTMs may become a new immunotherapy target for ESCA.

CMTM4 promotes the motility of colon cancer cells under radiation and is associated with an unfavorable neoadjuvant chemoradiotherapy response and patient survival in rectal cancer

Neoadjuvant chemoradiotherapy (nCRT) is the standard treatment for locally advanced rectal cancer (LARC). Pathological complete regression is closely linked to disease outcomes. However, biomarkers predicting nCRT response and patient survival are lacking for LARC. In the present study, the clinical characteristics and follow-up information of 228 patients with LARC were retrospectively collected. Immunohistochemistry (IHC), reverse transcription-quantitative PCR (RT-qPCR), Kaplan-Meier and multivariate analyses were used to evaluate the expression and predict the role of CKLF-like MARVEL transmembrane domain member 4 (CMTM4) in LARC. Additionally, lentiviral short hairpin (sh)RNA was used to interfere with CMTM4 expression. The phenotype of CMTM4-knockdown LoVo cells was determined by colony formation, migration and invasion assays under irradiation (IR) treatment. RNA-sequencing (RNA-seq) analysis was also used to explore the CMTM4-regulated genes in LoVo-shCMTM4 cells compared with control cells. RT-qPCR was then used to confirm the expression of these CMTM4-regulated genes. CMTM4 expression in pre-nCRT tissues indicated an unfavorable response and a short disease-free survival (DFS) with LARC. The expression of CMTM4 significantly increased following nCRT treatment. Additionally, CMTM4 knockdown increased the proliferation, migration and invasion of colon cancer cells; however, IR disrupted the cell migration and invasion induced by CMTM4 knockdown. RNA-seq analysis, the Tumor Immune Estimation Resource database and RT-qPCR indicated that CMTM4 was involved in different signaling pathways and regulated immune-related genes such as cluster of differentiation 66b, chemokine (CXC motif) ligand 8 (CXCL8) and programmed cell death 1. Furthermore, CXCL8 expression was found to be negatively associated with CMTM4 expression in patients with LARC by IHC and RT-qPCR. CXCL8 expression on invasion margin regions in post-operative tissues was also an inferior predictor of DFS in patients with LARC. In conclusion, CMTM4 may predict the nCRT response and outcomes in patients with LARC.

Cancer immunotherapeutic challenges from autophagy-immune checkpoint reciprocal regulation

Multiple strategies have been clinically employed as combination partners to enhance the therapeutic efficacy of immune checkpoint inhibitors (ICIs). Although these combinations have demonstrated improved effectiveness in some instances, each presents its own limitations. Autophagy-targeting therapy offers several advantages when combined with ICIs, including enhanced tumor immunogenicity, reduced side effects, and broader applicability to diverse patient populations. However, emerging evidence reveals complex reciprocal regulation between autophagy and immune checkpoints which may complicate combination treatments targeting these two systems. This review focuses on the reciprocal interplay between autophagy and immune checkpoints, and provides valuable guidelines for the determination and adjustment of therapeutic regimens in the future.

Preclinical in vitro models of HNSCC and their role in drug discovery - an emphasis on the cancer microenvironment and microbiota

INTRODUCTION

Head and neck squamous cell carcinoma (HNSCC) is the seventh most common cancer worldwide. Treatment options and patient outcomes have not improved significantly over the past decades, increasing the need for better preclinical models. Holistic approaches that include an intact and functional immune compartment along with the patient's individual tumor microbiome will help improve the predictive value of novel drug efficacy.

AREAS COVERED

In this review, we describe the challenges of modeling the complex and heterogeneous tumor landscape in HNSCC and the importance of sophisticated patient-specific 3D in vitro models to pave the way for clinical trials with novel immunomodulatory drugs. We also discuss the impact of the tumor microbiome and the potential implications for prospective drug screening and validation trials.

EXPERT OPINION

The repertoire of well-characterized preclinical 3D in vitro models continues to grow. With the increasing attention to the complex cellular, immunological, molecular, and spatio-temporal characteristics of tumors, well-designed proof-of-concept studies to test novel drug efficacy are on the verge of providing valuable, practice-changing insights for clinical trials. Bringing together expertise and improving collaboration between clinicians, academics, and regulatory agencies will facilitate the translation of preclinical findings into clinically meaningful outcomes.

Phase separation of chimeric antigen receptor promotes immunological synapse maturation and persistent cytotoxicity

Major challenges of chimeric antigen receptor (CAR)-T cell therapy include poor antigen sensitivity and cell persistence. Here, we report a solution to these issues by exploiting CAR phase separation. We found that incorporation of an engineered T cell receptor CD3ε motif, EB6I, into the conventional 28Z or BBZ CAR induced self-phase separation through cation-π interactions. EB6I CAR formed a mature immunological synapse with the CD2 corolla to transduce efficient antigen and costimulatory signaling, although its tonic signaling remained low. Functionally, EB6I CAR-T cells exhibited improved signaling and cytotoxicity against low-antigen tumor cells and persistent tumor-killing function. In multiple primary and relapsed murine tumor models, EB6I CAR-T cells exerted better antitumor functions than conventional CAR-T cells against blood and solid cancers. This study thus unveils a CAR engineering strategy to improve CAR-T cell immunity by leveraging molecular condensation and signaling integration.

The Atlantic Cod MHC I compartment has the properties needed for cross-presentation in the absence of MHC II

Atlantic cod has a peculiar immune system, characterized by the loss of Major Histocompatibility Complex (MHC) class II pathway, and an extreme expansion of the MHC class I gene repertoire. This has led to the hypothesis that some of the MHC I variants have replaced MHC II by presenting exogenous-peptides in a process similar to cross-presentation. In mammals, MHC I loads endogenous antigens in the endoplasmic reticulum, but we recently found that different Atlantic cod MHC I gene variants traffic to endolysosomes. There, they colocalize with Tapasin and other components of the peptide-loading complex, indicating a plausible peptide-loading system outside the endoplasmic reticulum. In this study, we further characterize the identity of the Atlantic cod MHC I compartment (cMIC). We found that, similarly to mammalian MHC II compartment, cMIC contains late endosomal markers such as Rab7, LAMP1 and CD63. Furthermore, we identified Hsp90b1 (also known as grp94) and LRP1 (also known as CD91) as interactors of MHC I by mass spectrometry. As these two proteins are involved in cross-presentation in mammals, this further suggests that Atlantic cod MHC I might use a similar mechanism to present exogenous peptides, thus, compensating for the absence of MHC II.

Revisiting T-cell adhesion molecules as potential targets for cancer immunotherapy: CD226 and CD2

Cancer immunotherapy aims to initiate or amplify immune responses that eliminate cancer cells and create immune memory to prevent relapse. Immune checkpoint inhibitors (ICIs), which target coinhibitory receptors on immune effector cells, such as CTLA-4 and PD-(L)1, have made significant strides in cancer treatment. However, they still face challenges in achieving widespread and durable responses. The effectiveness of anticancer immunity, which is determined by the interplay of coinhibitory and costimulatory signals in tumor-infiltrating immune cells, highlights the potential of costimulatory receptors as key targets for immunotherapy. This review explores our current understanding of the functions of CD2 and CD226, placing a special emphasis on their potential as novel agonist targets for cancer immunotherapy. CD2 and CD226, which are present mainly on T and NK cells, serve important functions in cell adhesion and recognition. These molecules are now recognized for their costimulatory benefits, particularly in the context of overcoming T-cell exhaustion and boosting antitumor responses. The importance of CD226, especially in anti-TIGIT therapy, along with the CD2‒CD58 axis in overcoming resistance to ICI or chimeric antigen receptor (CAR) T-cell therapies provides valuable insights into advancing beyond the current barriers of cancer immunotherapy, underscoring their promise as targets for novel agonist therapy.

Evaluation of the effect of GSK-3β on liver cancer based on the PI3K/AKT pathway

The PI3K/AKT/GSK-3β signaling pathway plays a pivotal role in numerous physiological and pathological processes, including cell proliferation, apoptosis, differentiation, and metabolic regulation. Aberrant activation of the PI3K/AKT pathway is intricately linked to development of tumor. GSK-3β, belonging to the serine/threonine protein kinase family, is crucial in the pathogenesis of liver cancer. As a key rate-limiting enzyme in the glucose metabolism pathway, GSK-3β significantly impacts the growth, proliferation, metastasis, and apoptosis of liver cancer cells. It is also implicated in chemotherapy resistance. Elevated expression of GSK-3β diminishes the sensitivity of liver cancer cells to chemotherapeutic agents, thereby playing a substantial role in the development of drug resistance. Consequently, targeting of GSK-3β, particularly within the PI3K/AKT signaling pathway, is regarded as a promising therapeutic strategy for liver cancer. The precise identification and subsequent modulation of this pathway represent a substantial potential for innovative clinical interventions in the management of liver cancer.

Impact of high-salt diet in health and diseases and its role in pursuit of cancer immunotherapy by modulating gut microbiome

Cancer chemotherapy remains an area of concern, as many of the therapies are uncomfortable involving side effects and unpleasant experiences. These factors could further reduce patient's quality of life, and even endanger their life. Many therapeutic strategies have been tried to reduce the unpleasant side effects and increase the treatment effectiveness; however, none have shown to have promising effects. One of the main hindrances to cancer therapy is the escape strategies by tumor cells to the immune attack. Promoting inflammation in the tumor microenvironment is the cornerstone and key therapeutic target in cancer chemotherapy. High-salt diet (HSD) intake, though it has deleterious effects on human health by promoting chronic inflammation, is found to be advantageous in the tumor microenvironment. Studies identified HSD favors an increased abundance of Bifidobacterium species in the tumor environment due to gut barrier alteration, which, in turn, promotes inflammation and favors improved response to cancer chemotherapy. A review of the literature was carried out to find out the effects of an HSD on health and diseases, with special mention of its effect on cancer chemotherapy. Studies emphasized HSD would block the myeloid-derived suppressor cells which will enhance the tumor immunity. Exploration of the precise mechanism of simple HSD regime/ingestion of specific bacterial species as probiotics will be effective and essential to formulate the game-changing cancer chemotherapy. With the modern era of healthcare moving toward precision medicine where the physician can choose the treatment option suitable for the individual, HSD regime/ingestion of specific bacterial species can be considered.

Clinical significance of immune-related antigen CD58 in gliomas and analysis of its potential core related gene clusters

Background

The clinical significance of immune-related antigen CD58 in gliomas remains uncertain. The aim of this study was to examine the clinical importance and possible core related genes of CD58 in gliomas.

Methods

Pan-cancer analysis was to observe the association between CD58 and different tumors, glioma RNA sequencing data and clinical sample analyses were used to observe the relationship between CD58 and glioma, shRNA interference models were to observe the impact of CD58 on glioma cell function, and four glioma datasets and two online analysis platforms were used to explore the core related genes affecting the correlation between CD58 and glioma.

Results

High CD58 expression was associated with worse prognosis in various tumors and higher malignancy in glioma. Down regulation of CD58 expression was linked to decreased proliferation, increased apoptosis, and reduced metastasis in glioma cells. The pathways involved in CD58-related effects were enriched for immune cell adhesion and immune factor activation, and the core genes were CASP1, CCL2, IL18, MYD88, PTPRC, and TLR2. The signature of CD58 and its core-related genes showed superior predictive power for glioma prognosis.

Conclusion

High CD58 expression is correlated with more malignant glioma types, and also an independent risk factor for mortality in glioma. CD58 and its core-related genes may serve as novel biomarkers for diagnosing and treating glioma.

From patient tissue correlates to molecular mechanisms of cancer immune evasion: the emerging role of CD58 and PD-L1 co-regulation via CMTM6

Immune evasion is a hallmark of cancer, yet the underlying mechanisms are often unknown in many patients. Using single-cell transcriptomics analysis, we previously identified the co-stimulator CD58 as part of a cancer cell-intrinsic immune checkpoint resistance signature in patient melanoma tissue. We subsequently validated CD58 loss as a driver of immune evasion using a patient-derived co-culture model of cancer and cytotoxic tumor-infiltrating lymphocytes in a pooled single-cell perturbation experiment, where we additionally observed concurrent upregulation of PD-L1 protein expression in melanoma cells with CD58 loss. In our most recent study, we uncovered the mechanisms of immune evasion mediated by CD58 loss, including impaired T cell activation and infiltration within tumors, as well as inhibitory signaling by PD-L1 via a shared regulator, CMTM6. Thus, cancer cell-intrinsic reduction of CD58 represents a multi-faceted determinant of immune evasion. Furthermore, its reciprocal interaction with PD-L1 via CMTM6 provides critical insights into how co-inhibitory and co-stimulatory immune cues are regulated.