CD8+ T cell states in human cancer: insights from single-cell analysis

Research on the mechanism of exosomes from different sources influencing the progression of lung cancer

As a key regulator of intercellular communication, exosomes are essential for tumor cells. In our study, we will explore the mechanisms of exosomes from different sources on lung cancer. We isolated CD8+T cells and cancer-associated fibroblasts (CAFs) from venous blood and tumor tissues of lung cancer patients, and isolated exosomes. MiR-2682 was high expression in CD8+T-derived exosomes, and lncRNA-FOXD3-AS1 was upregulated in CAF-derived exosomes. Online bioinformatics database analysis showed that RNA Binding Motif Protein 39 (RBM39) was identified as the target of miR-2682, and eukaryotic translation initiation factors 3B (EIF3B) was identified as the RNA binding protein of FOXD3-AS1. CD8+T-derived exosomes inhibited the growth of A549 cells and promoted apoptosis, while miR-2682 inhibits reversed these effects of CD8+T-derived exosomes. CAF-derived exosomes promoted the growth of A549 cells and inhibited apoptosis, while FOXD3-AS1 siRNA reversed the effect of CAF-derived exosomes. Mechanism studies have found that miR-2682 inhibits the growth of lung cancer cells by inhibiting the expression of RBM39. FOXD3-AS1 promoted the growth of lung cancer cells by binding to EIF3B. In vivo experiments showed that CD8+T cell-derived exosome miR-2682 inhibited lung cancer tumor formation, while CAF-derived exosome FOXD3-AS1 promoted lung cancer tumor formation. This study provides mechanistic insights into the role of miR-2682 and FOXD3-AS1 in lung cancer progression and provides new strategies for lung cancer treatment.

Myeloid-T cell interplay and cell state transitions associated with checkpoint inhibitor response in melanoma

BACKGROUND

The treatment of melanoma, the deadliest form of skin cancer, has greatly benefited from immunotherapy. However, many patients do not show a durable response, which is only partially explained by known resistance mechanisms.

METHODS

We performed single-cell RNA sequencing of tumor immune infiltrates and matched peripheral blood mononuclear cells of 22 checkpoint inhibitor (CPI)-naive stage III-IV metastatic melanoma patients. After sample collection, the same patients received CPI treatment, and their response was assessed.

FINDINGS

CPI responders showed high levels of classical monocytes in peripheral blood, which preferentially transitioned toward CXCL9-expressing macrophages in tumors. Trajectories of tumor-infiltrating CD8+ T cells diverged at the level of effector memory/stem-like T cells, with non-responder cells progressing into a state characterized by cellular stress and apoptosis-related gene expression. Consistently, predicted non-responder-enriched myeloid-T/natural killer cell interactions were primarily immunosuppressive, while responder-enriched interactions were supportive of T cell priming and effector function.

CONCLUSIONS

Our study illustrates that the tumor immune microenvironment prior to CPI treatment can be indicative of response. In perspective, modulating the myeloid and/or effector cell compartment by altering the described cell interactions and transitions could improve immunotherapy response.

FUNDING

This research was funded by Roche Pharma Research and Early Development.

Unraveling pancreatic ductal adenocarcinoma immune prognostic signature through a naive B cell gene set

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC), a leading cause of cancer mortality, has a complex pathogenesis involving various immune cells, including B cells and their subpopulations. Despite emerging research on the role of these cells within the tumor microenvironment (TME), the detailed molecular interactions with tumor-infiltrating immune cells (TIICs) are not fully understood.

METHODS

We applied CIBERSORT to quantify TIICs and naive B cells, which are prognostic for PDAC. Marker genes from scRNA-seq and modular genes from weighted gene co-expression network analysis (WGCNA) were integrated to identify naive B cell-related genes. A prognostic signature was constructed utilizing ten machine-learning algorithms, with validation in external cohorts. We further assessed the immune cell diversity, ESTIMATE scores, and immune checkpoint genes (ICGs) between patient groups stratified by risk to clarify the immune landscape in PDAC.

RESULTS

Our analysis identified 994 naive B cell-related genes across single-cell and bulk transcriptomes, with 247 linked to overall survival. We developed a 12-gene prognostic signature using Lasso and plsRcox algorithms, which was confirmed by 10-fold cross-validation and showed robust predictive power in training and real-world cohorts. Notably, we observed substantial differences in immune infiltration between patients with high and low risk.

CONCLUSION

Our study presents a robust prognostic signature that effectively maps the complex immune interactions in PDAC, emphasizing the critical function of naive B cells and suggesting new avenues for immunotherapeutic interventions. This signature has potential clinical applications in personalizing PDAC treatment, enhancing the understanding of immune dynamics, and guiding immunotherapy strategies.

Human effector CD8+ T cells with an activated and exhausted-like phenotype control tumour growth in vivo in a humanized tumour model

BACKGROUND

Humanized tumour models could be particularly valuable for cancer immunotherapy research, as they may better reflect human-specific aspects of the interfaces between tumour and immune system of human cancer. However, endogenous antitumour immunity in humanized models is still largely undefined.

METHODS

We established an autologous humanized mouse tumour model by using NSG mice reconstituted with human immune cells from hematopoietic progenitors and tumours generated from transformed autologous human B cells. We demonstrate growth of solid lymphoid tumours after subcutaneous implantation, infiltration by endogenous human immune cells and immunocompetence of the model.

FINDINGS

We found human T cell subsets described in human cancer, including progenitor exhausted (Tpex), terminally exhausted (Tex-term) and tissue-resident (TRM) cells in tumour-bearing humanized mice with accumulation of Tex-term and TRM in the tumour. In addition, we identified tumour-reactive CD8+ T cells through expression of CD137. This subpopulation of de novo arising human CD137+ CD8+ T cells displayed a highly proliferative, fully activated effector and exhausted-like phenotype with enhanced expression of activation and exhaustion markers like PD-1, CD39, CD160, TIM-3, TIGIT and TOX, the senescence marker CD57 (B3GAT1) and cytolytic effector molecules such as PRF1, GZMH and NKG7. Moreover, these CD137+ CD8+ T cells exhibited tumour-specific clonal expansion and presented signature overlap with tumour-reactive CD8+ T cells described in human cancer. We demonstrate superior anticancer activity of this activated and exhausted-like human CD8+ T cell subset by adoptive transfer experiments using recipients bearing autologous human tumours. Mice adoptively transferred with CD137+ CD8+ T cells showed reduced tumour growth and higher CD8+ T cell tumour infiltration, correlating with control of human tumours.

INTERPRETATION

We established an immunocompetent humanized tumour model, providing a tool for immunotherapy research and defined effective anticancer activity of human effector CD8+ T cells with an activated and exhausted-like phenotype, supporting clinical exploration of such cells in adoptive T cell therapies.

FUNDING

Swiss Cancer Research foundation.

Spatiotemporal single-cell analysis decodes cellular dynamics underlying different responses to immunotherapy in colorectal cancer

Expanding the efficacy of immune checkpoint blockade (ICB) in colorectal cancer (CRC) presses for a comprehensive understanding of treatment responsiveness. Here, we analyze multiple sequential single-cell samples from 22 patients undergoing PD-1 blockade to map the evolution of local and systemic immunity of CRC patients. In tumors, we identify coordinated cellular programs exhibiting distinct response associations. Specifically, exhausted T (Tex) or tumor-reactive-like CD8+ T (Ttr-like) cells are closely related to treatment efficacy, and Tex cells show correlated proportion changes with multiple other tumor-enriched cell types following PD-1 blockade. In addition, we reveal the less-exhausted phenotype of blood-associated Ttr-like cells in tumors and find that their higher abundance suggests better treatment outcomes. Finally, a higher major histocompatibility complex (MHC) II-related signature in circulating CD8+ T cells at baseline is linked to superior responses. Our study provides insights into the spatiotemporal cellular dynamics following neoadjuvant PD-1 blockade in CRC.

An immune biomarker associated with EMT serves as a predictor for prognosis and drug response in bladder cancer

BACKGROUND

Bladder cancer (BLCA), which develops from the upper endometrial of the bladder, is the sixth most prevalent cancer across the globe. WDHD1 (WD repeat and HMG-box DNA binding protein 1 gene) directly affects signaling, the cell cycle, and the development of the cell skeleton. Uncertainty surrounds WDHD1's function in BLCA immunity and prognosis, though.

MATERIALS AND METHODS

Using weighed gene co-expression network analysis (WGCNA), initially, we first identified 32 risk factors in genes with differential expression for this investigation. Then, using a variety of bioinformatic techniques and experimental validation, we examined the connections between WDHD1 and BLCA expression, clinical pathological traits, WDHD1-related proteins, upper-skin-intermediate conversion (EMT), immune cell immersion, convergence factors, immune markers, and drug sensitivity.

RESULT

The findings demonstrated that we constructed a 32-gene risk-predicting model where WDHD1 was elevated as a representative gene expression in BLCA and related to a range of clinical traits. Furthermore, high WDHD1 expression was a standalone predictor associated with a worse survival rate. The most commonly recruited cells and their evolutionary patterns were highlighted to better comprehend WDHD1's function in cancer. High WDHD1 expression was associated with many aspects of immunology. Finally, the study found that individuals with high expression of WDHD1 were drug-sensitive to four different broad-spectrum anti-cancer drugs.

CONCLUSION

These results describe dynamic changes in the tumor microenvironment in BLCA and provide evidence for the hypothesis that WDHD1 is a novel biomarker of tumor development. WDHD1 may therefore be a useful target for the detection and management of BLCA.

Establishment of an ovarian cancer exhausted CD8+T cells-related genes model by integrated analysis of scRNA-seq and bulk RNA-seq

Ovarian cancer (OC) was the fifth leading cause of cancer death and the deadliest gynecological cancer in women. This was largely attributed to its late diagnosis, high therapeutic resistance, and a dearth of effective treatments. Clinical and preclinical studies have revealed that tumor-infiltrating CD8+T cells often lost their effector function, the dysfunctional state of CD8+T cells was known as exhaustion. Our objective was to identify genes associated with exhausted CD8+T cells (CD8TEXGs) and their prognostic significance in OC. We downloaded the RNA-seq and clinical data from the Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. CD8TEXGs were initially identified from single-cell RNA-seq (scRNA-seq) datasets, then univariate Cox regression, the least absolute shrinkage and selection operator (LASSO), and multivariate Cox regression were utilized to calculate risk score and to develop the CD8TEXGs risk signature. Kaplan-Meier analysis, univariate Cox regression, multivariate Cox regression, time-dependent receiver operating characteristics (ROC), nomogram, and calibration were conducted to verify and evaluate the risk signature. Gene set enrichment analyses (GSEA) in the risk groups were used to figure out the closely correlated pathways with the risk group. The role of risk score has been further explored in the homologous recombination repair deficiency (HRD), BRAC1/2 gene mutations and tumor mutation burden (TMB). A risk signature with 4 CD8TEXGs in OC was finally built in the TCGA database and further validated in large GEO cohorts. The signature also demonstrated broad applicability across various types of cancer in the pan-cancer analysis. The high-risk score was significantly associated with a worse prognosis and the risk score was proven to be an independent prognostic biomarker. The 1-, 3-, and 5-years ROC values, nomogram, calibration, and comparison with the previously published models confirmed the excellent prediction power of this model. The low-risk group patients tended to exhibit a higher HRD score, BRCA1/2 gene mutation ratio and TMB. The low-risk group patients were more sensitive to Poly-ADP-ribose polymerase inhibitors (PARPi). Our findings of the prognostic value of CD8TEXGs in prognosis and drug response provided valuable insights into the molecular mechanisms and clinical management of OC.

Path to bacteriotherapy: From bacterial engineering to therapeutic perspectives

The major reason for the failure of conventional therapies is the heterogeneity and complexity of tumor microenvironments (TMEs). Many malignant tumors reprogram their surface antigens to evade the immune surveillance, leading to reduced antigen-presenting cells and hindered T-cell activation. Bacteria-mediated cancer immunotherapy has been extensively investigated in recent years. Scientists have ingeniously modified bacteria using synthetic biology and nanotechnology to enhance their biosafety with high tumor specificity, resulting in robust anticancer immune responses. To enhance the antitumor efficacy, therapeutic proteins, cytokines, nanoparticles, and chemotherapeutic drugs have been efficiently delivered using engineered bacteria. This review provides a comprehensive understanding of oncolytic bacterial therapies, covering bacterial design and the intricate interactions within TMEs. Additionally, it offers an in-depth comparison of the current techniques used for bacterial modification, both internally and externally, to maximize their therapeutic effectiveness. Finally, we outlined the challenges and opportunities ahead in the clinical application of oncolytic bacterial therapies.

Deep pan-cancer analysis and multi-omics evidence reveal that ALG3 inhibits CD8+ T cell infiltration by suppressing chemokine secretion and is associated with 5-fluorouracil sensitivity

BACKGROUND

α-1,3-mannosyltransferase (ALG3) holds significance as a key member within the mannosyltransferase family. Nevertheless, the exact function of ALG3 in cancer remains ambiguous. Consequently, the current research aimed to examine the function and potential mechanisms of ALG3 in various types of cancer.

METHODS

Deep pan-cancer analyses were conducted to investigate the expression patterns, prognostic value, genetic variations, single-cell omics, immunology, and drug responses associated with ALG3. Subsequently, in vitro experiments were executed to ascertain the biological role of ALG3 in breast cancer. Moreover, the link between ALG3 and CD8+ T cells was verified using immunofluorescence. Lastly, the association between ALG3 and chemokines was assessed using qRT-PCR and ELISA.

RESULTS

Deep pan-cancer analysis demonstrated a heightened expression of ALG3 in the majority of tumors based on multi-omics evidence. ALG3 emerges as a diagnostic and prognostic biomarker across diverse cancer types. In addition, ALG3 participates in regulating the tumor immune microenvironment. Elevated levels of ALG3 were closely linked to the infiltration of bone marrow-derived suppressor cells (MDSC) and CD8+ T cells. According to in vitro experiments, ALG3 promotes proliferation and migration of breast cancer cells. Moreover, ALG3 inhibited CD8+ T cell infiltration by suppressing chemokine secretion. Finally, the inhibition of ALG3 enhanced the responsiveness of breast cancer cells to 5-fluorouracil treatment.

CONCLUSION

ALG3 shows potential as both a prognostic indicator and immune infiltration biomarker across various types of cancer. Inhibition of ALG3 may represent a promising therapeutic strategy for tumor treatment.

CD8-Targeted IL2 Unleashes Tumor-Specific Immunity in Human Cancer Tissue by Reviving the Dysfunctional T-cell Pool

Tumor-specific CD8+ T cells are key effectors of antitumor immunity but are often rendered dysfunctional in the tumor microenvironment. Immune-checkpoint blockade can restore antitumor T-cell function in some patients; however, most do not respond to this therapy, often despite T-cell infiltration in their tumors. We here explored a CD8-targeted IL2 fusion molecule (CD8-IL2) to selectively reactivate intratumoral CD8+ T cells in patient-derived tumor fragments. Treatment with CD8-IL2 broadly armed intratumoral CD8+ T cells with enhanced effector capacity, thereby specifically enabling reinvigoration of the dysfunctional T-cell pool to elicit potent immune activity. Notably, the revival of dysfunctional T cells to mediate effector activity by CD8-IL2 depended on simultaneous antigen recognition and was quantitatively and qualitatively superior to that achieved by PD-1 blockade. Finally, CD8-IL2 was able to functionally reinvigorate T cells in tumors resistant to anti-PD-1, underscoring its potential as a novel treatment strategy for patients with cancer. Significance: Reinvigorating T cells is crucial for response to checkpoint blockade therapy. However, emerging evidence suggests that the PD-1/PD-L1 axis is not the sole impediment for activating T cells within tumors. Selectively targeting cytokines toward specific T-cell subsets might overcome these barriers and stimulate T cells within resistant tumors. See related article by Moynihan et al., p. 1206 (32).

CAFs and T cells interplay: The emergence of a new arena in cancer combat

The interaction between the immune system and the tumor matrix has a huge impact on the progression and treatment of cancer. This paper summarizes and discusses the crosstalk between T cells and cancer-associated fibroblasts (CAFs). CAFs can also produce inhibitors that counteract the function of T cells and promote tumor immune escape, while T cells can also engage in complex two-way interactions with CAFs through direct cell contact, the exchange of soluble factors such as cytokines, and the remodeling of the extracellular matrix. Precise targeted intervention can effectively reverse tumor-promoting crosstalk between T cells and CAFs, improve anti-tumor immune response, and provide a new perspective for cancer treatment. Therefore, it is important to deeply understand the mechanism of crosstalk between T cells and CAFs. This review aims to outline the underlying mechanisms of these interactions and discuss potential therapeutic strategies that may become fundamental tools in the treatment of cancer, especially hard-to-cure cancers.

Anti-VEGFR2-Interferon α Promotes the Infiltration of CD8+ T Cells in Colorectal Cancer by Upregulating the Expression of CCL5

SUMMARY

Immunocytokines are a promising immunotherapeutic approach in cancer therapy. Anti-VEGFR2-interferon α (IFNα) suppressed colorectal cancer (CRC) growth and enhanced CD8 + T-cell infiltration in the tumor microenvironment, exhibiting great clinical translational potential. However, the mechanism of how the anti-VEGFR2-IFNα recruits T cells has not been elucidated. Here, we demonstrated that anti-VEGFR2-IFNα suppressed CRC metastasis and enhanced CD8 + T-cell infiltration. RNA sequencing revealed a transcriptional activation of CCL5 in metastatic CRC cells, which was correlated with T-cell infiltration. IFNα but not anti-VEGFR2 could further upregulate CCL5 in tumors. In immunocompetent mice, both IFNα and anti-VEGFR2-IFNα increased the subset of tumor-infiltrating CD8 + T cells through upregulation of CCL5. Knocking down CCL5 in tumor cells attenuated the infiltration of CD8 + T cells and dampened the antitumor efficacy of anti-VEGFR2-IFNα treatment. We, therefore, propose upregulation of CCL5 is a key to enhance infiltration of CD8 + T cells in metastatic CRC with IFNα and IFNα-based immunocytokine treatments. These findings may help the development of IFNα related immune cytokines for the treatment of less infiltrated tumors.

Landscape and prognostic values of lymphocytes in patients with hepatocellular carcinoma undergoing transarterial embolization

Transarterial embolization, the first-line treatment for hepatocellular carcinoma, does not always lead to promising outcomes in all patients. A better understanding of how the immune lymphocyte changes after transarterial embolization might be the key to improve the efficacy of transarterial embolization. However, there are few studies evaluating immune lymphocytes in transarterial embolization patients. Therefore, we aimed to evaluate the short- and long-term effects of transarterial embolization on lymphocyte subsets in patients with hepatocellular carcinoma to identify those that predict transarterial embolization prognosis. Peripheral blood samples were collected from 44 patients with hepatocellular carcinoma at the following time points: 1 d before the initial transarterial embolization, 3 d after the initial transarterial embolization, and 1 mo after the initial transarterial embolization and subjected to peripheral blood mononuclear cell isolation and flow cytometry. Dynamic changes in 75 lymphocyte subsets were recorded, and their absolute counts were calculated. Tumor assessments were made every 4 to 6 wk via computed tomography or magnetic resonance imaging. Our results revealed that almost all lymphocyte subsets fluctuated 3 d after transarterial embolization, but only Tfh and B cells decreased 1 mo after transarterial embolization. Univariate and multivariate Cox regression showed that high levels of Th2 and conventional killer Vδ2 cells were associated with longer progressive-free survival after transarterial embolization. Longer overall survival after transarterial embolization was associated with high levels of Th17 and viral infection-specific Vδ1 cells and low levels of immature natural killer cells. In conclusion, transarterial embolization has a dynamic influence on the status of lymphocytes. Accordingly, several lymphocyte subsets can be used as prognostic markers for transarterial embolization.

Escape from T-cell-targeting immunotherapies in acute myeloid leukemia

ABSTRACT

Single-cell and spatial multimodal technologies have propelled discoveries of the solid tumor microenvironment (TME) molecular features and their correlation with clinical response and resistance to immunotherapy. Computational tools are incessantly being developed to characterize tumor-infiltrating immune cells and to model tumor immune escape. These advances have led to substantial research into T-cell hypofunctional states in the TME and their reinvigoration with T-cell-targeting approaches, including checkpoint inhibitors (CPIs). Until recently, we lacked a high-dimensional picture of the acute myeloid leukemia (AML) TME, including compositional and functional differences in immune cells between disease onset and postchemotherapy or posttransplantation relapse, and the dynamic interplay between immune cells and AML blasts at various maturation stages. AML subgroups with heightened interferon gamma (IFN-γ) signaling were shown to derive clinical benefit from CD123×CD3-bispecific dual-affinity retargeting molecules and CPIs, while being less likely to respond to standard-of-care cytotoxic chemotherapy. In this review, we first highlight recent progress into deciphering immune effector states in AML (including T-cell exhaustion and senescence), oncogenic signaling mechanisms that could reduce the susceptibility of AML cells to T-cell-mediated killing, and the dichotomous roles of type I and II IFN in antitumor immunity. In the second part, we discuss how this knowledge could be translated into opportunities to manipulate the AML TME with the aim to overcome resistance to CPIs and other T-cell immunotherapies, building on recent success stories in the solid tumor field, and we provide an outlook for the future.

Pan-cancer mapping of single CD8+ T cell profiles reveals a TCF1:CXCR6 axis regulating CD28 co-stimulation and anti-tumor immunity

CD8+ T cells must persist and function in diverse tumor microenvironments to exert their effects. Thus, understanding common underlying expression programs could better inform the next generation of immunotherapies. We apply a generalizable matrix factorization algorithm that recovers both shared and context-specific expression programs from diverse datasets to a single-cell RNA sequencing (scRNA-seq) compendium of 33,161 CD8+ T cells from 132 patients with seven human cancers. Our meta-single-cell analyses uncover a pan-cancer T cell dysfunction program that predicts clinical non-response to checkpoint blockade in melanoma and highlights CXCR6 as a pan-cancer marker of chronically activated T cells. Cxcr6 is trans-activated by AP-1 and repressed by TCF1. Using mouse models, we show that Cxcr6 deletion in CD8+ T cells increases apoptosis of PD1+TIM3+ cells, dampens CD28 signaling, and compromises tumor growth control. Our study uncovers a TCF1:CXCR6 axis that counterbalances PD1-mediated suppression of CD8+ cell responses and is essential for effective anti-tumor immunity.

Prognostic Role of Tumor-Infiltrating Lymphocytes in Oral Squamous Cell Carcinoma

BACKGROUND

In oral squamous cell carcinoma (OSCC), the tumor-node-metastasis (TNM) staging system is a significant factor that influences prognosis and treatment decisions for OSCC patients. Unfortunately, TNM staging does not consistently predict patient prognosis and patients with identical clinicopathological characteristics may have vastly different survival outcomes. Host immunity plays an important role in tumor progression but is not included in the TNM staging system. Tumor-infiltrating lymphocytes (TILs) are part of the host immune response that recognizes tumor cells; and the presence of TILs has emerged as potential candidates for prognostic markers for many types of cancers. The present study aims to determine the association of T cell-specific markers (CD3, CD4, CD8, and FOXP3) with clinicopathological characteristics and survival outcomes in OSCC patients. The prognostic value of CD3, CD4, and CD8 will also be evaluated based on tumor stage.

METHODS

Tissue microarrays were constructed containing 231 OSCC cases and analyzed by immunohistochemical staining for the expression of CD3, CD4, CD8, and FOXP3. The expression scores for each marker were correlated with clinicopathological parameters and survival outcomes. The prognostic impact of CD3, CD4 and CD8 were further analyzed based on tumor stage (early or advanced).

RESULTS

CD3, CD4, and CD8 were found to be significantly associated with both overall survival and progression-free survival using univariate analysis. However, none of these markers were found to independently predict the survival outcomes of OSCC using multivariate analysis. Only conventional factors such as nodal status, tumor differentiation and perineural invasion (PNI) were independent predictors of survival outcomes, with nodal status being the strongest independent predictor. Additionally, low CD4 (but not CD3 or CD8) expression was found to identify early-stage OSCC patients with exceptionally poor prognosis which was similar to that of advanced staged OSCC patients.

CONCLUSIONS

TIL markers such as CD3, CD4, CD8, and FOXP3 can predict the survival outcomes of OSCC patients, but do not serve as independent prognostic markers as found with conventional factors (i.e. nodal status, tumor differentiation and PNI). CD4 expression may assist with risk stratification in early-stage OSCC patients which may influence treatment planning and decision making for early-stage OSCC patients.

Deciphering extracellular vesicles protein cargo in pancreatic cancer

Pancreatic ductal adenocarcinoma (PDAC) presents a significant therapeutic challenge as it is frequently diagnosed at advanced inoperable stages. Therefore, the development of a reliable screening tool for PDAC is crucial for effective prevention and treatment. Extracellular vesicles (EVs), characterized by their cup-shaped lipid bilayer structure and ubiquitous release from various cell types, offer notable advantages as an emerging liquid biopsy technique that is rapid, minimally invasive, easily sampled, and cost-effective. While EVs play a substantial role in cancer progression, EV proteins serve as direct mediators of diverse cellular behaviors and have immense potential as biomarkers for PDAC diagnosis and prognostication. This review provides an overview of EV proteins regarding PDAC diagnosis and prognostic implications as well as disease progression.

Tumor initiation and early tumorigenesis: molecular mechanisms and interventional targets

Tumorigenesis is a multistep process, with oncogenic mutations in a normal cell conferring clonal advantage as the initial event. However, despite pervasive somatic mutations and clonal expansion in normal tissues, their transformation into cancer remains a rare event, indicating the presence of additional driver events for progression to an irreversible, highly heterogeneous, and invasive lesion. Recently, researchers are emphasizing the mechanisms of environmental tumor risk factors and epigenetic alterations that are profoundly influencing early clonal expansion and malignant evolution, independently of inducing mutations. Additionally, clonal evolution in tumorigenesis reflects a multifaceted interplay between cell-intrinsic identities and various cell-extrinsic factors that exert selective pressures to either restrain uncontrolled proliferation or allow specific clones to progress into tumors. However, the mechanisms by which driver events induce both intrinsic cellular competency and remodel environmental stress to facilitate malignant transformation are not fully understood. In this review, we summarize the genetic, epigenetic, and external driver events, and their effects on the co-evolution of the transformed cells and their ecosystem during tumor initiation and early malignant evolution. A deeper understanding of the earliest molecular events holds promise for translational applications, predicting individuals at high-risk of tumor and developing strategies to intercept malignant transformation.

Nicotinamide metabolism face-off between macrophages and fibroblasts manipulates the microenvironment in gastric cancer

Immune checkpoint blockade has led to breakthroughs in the treatment of advanced gastric cancer. However, the prominent heterogeneity in gastric cancer, notably the heterogeneity of the tumor microenvironment, highlights the idea that the antitumor response is a reflection of multifactorial interactions. Through transcriptomic analysis and dynamic plasma sample analysis, we identified a metabolic "face-off" mechanism within the tumor microenvironment, as shown by the dual prognostic significance of nicotinamide metabolism. Specifically, macrophages and fibroblasts expressing the rate-limiting enzymes nicotinamide phosphoribosyltransferase and nicotinamide N-methyltransferase, respectively, regulate the nicotinamide/1-methylnicotinamide ratio and CD8+ T cell function. Mechanistically, nicotinamide N-methyltransferase is transcriptionally activated by the NOTCH pathway transcription factor RBP-J and is further inhibited by macrophage-derived extracellular vesicles containing nicotinamide phosphoribosyltransferase via the SIRT1/NICD axis. Manipulating nicotinamide metabolism through autologous injection of extracellular vesicles restored CD8+ T cell cytotoxicity and the anti-PD-1 response in gastric cancer.

Single-cell multiomics profiling reveals heterogeneous transcriptional programs and microenvironment in DSRCTs

Desmoplastic small round cell tumor (DSRCT) is a rare, aggressive sarcoma driven by the EWSR1::WT1 chimeric transcription factor. Despite this unique oncogenic driver, DSRCT displays a polyphenotypic differentiation of unknown causality. Using single-cell multi-omics on 12 samples from five patients, we find that DSRCT tumor cells cluster into consistent subpopulations with partially overlapping lineage- and metabolism-related transcriptional programs. In vitro modeling shows that high EWSR1::WT1 DNA-binding activity associates with most lineage-related states, in contrast to glycolytic and profibrotic states. Single-cell chromatin accessibility analysis suggests that EWSR1::WT1 binding site variability may drive distinct lineage-related transcriptional programs, supporting some level of cell-intrinsic plasticity. Spatial transcriptomics reveals that glycolytic and profibrotic states specifically localize within hypoxic niches at the periphery of tumor cell islets, suggesting an additional role of tumor cell-extrinsic microenvironmental cues. We finally identify a single-cell transcriptomics-derived epithelial signature associated with improved patient survival, highlighting the clinical relevance of our findings.

A Role of Effector CD 8 + T Cells Against Circulating Tumor Cells Cloaked with Platelets: Insights from a Mathematical Model

Cancer metastasis accounts for a majority of cancer-related deaths worldwide. Metastasis occurs when the primary tumor sheds cells into the blood and lymphatic circulation, thereby becoming circulating tumor cells (CTCs) that transverse through the circulatory system, extravasate the circulation and establish a secondary distant tumor. Accumulating evidence suggests that circulating effector CD 8 + T cells are able to recognize and attack arrested or extravasating CTCs, but this important antitumoral effect remains largely undefined. Recent studies highlighted the supporting role of activated platelets in CTCs's extravasation from the bloodstream, contributing to metastatic progression. In this work, a simple mathematical model describes how the primary tumor, CTCs, activated platelets and effector CD 8 + T cells participate in metastasis. The stability analysis reveals that for early dissemination of CTCs, effector CD 8 + T cells can present or keep secondary metastatic tumor burden at low equilibrium state. In contrast, for late dissemination of CTCs, effector CD 8 + T cells are unlikely to inhibit secondary tumor growth. Moreover, global sensitivity analysis demonstrates that the rate of the primary tumor growth, intravascular CTC proliferation, as well as the CD 8 + T cell proliferation, strongly affects the number of the secondary tumor cells. Additionally, model simulations indicate that an increase in CTC proliferation greatly contributes to tumor metastasis. Our simulations further illustrate that the higher the number of activated platelets on CTCs, the higher the probability of secondary tumor establishment. Intriguingly, from a mathematical immunology perspective, our simulations indicate that if the rate of effector CD 8 + T cell proliferation is high, then the secondary tumor formation can be considerably delayed, providing a window for adjuvant tumor control strategies. Collectively, our results suggest that the earlier the effector CD 8 + T cell response is enhanced the higher is the probability of preventing or delaying secondary tumor metastases.

The role of transforming growth factor-β (TGF-β) in the formation of exhausted CD8 + T cells

CD8 + T cells exert a critical role in eliminating cancers and chronic infections, and can provide long-term protective immunity. However, under the exposure of persistent antigen, CD8 + T cells can differentiate into terminally exhausted CD8 + T cells and lose the ability of immune surveillance and disease clearance. New insights into the molecular mechanisms of T-cell exhaustion suggest that it is a potential way to improve the efficacy of immunotherapy by restoring the function of exhausted CD8 + T cells. Transforming growth factor-β (TGF-β) is an important executor of immune homeostasis and tolerance, inhibiting the expansion and function of many components of the immune system. Recent studies have shown that TGF-β is one of the drivers for the development of exhausted CD8 + T cells. In this review, we summarized the role and mechanisms of TGF-β in the formation of exhausted CD8 + T cells and discussed ways to target those to ultimately enhance the efficacy of immunotherapy.

Preclinical Evaluation of 131I/18F-Labeled Covalent Small-Molecule Inhibitors for STING Status Imaging

The stimulator of interferon genes (STING) is a vital protein to the immune surveillance of the tumor microenvironment. In this study, we develop novel inhibitor-based radioligands and evaluate their feasibility for noninvasive visualization of STING expression in tumor-bearing mice. Analogous compounds to STING inhibitors C170 and C176 were synthesized and labeled with 131I and 18F to attain [131I]I-NFIP and [18F]F-NFEP, respectively. The radiosynthesis was achieved with high radiochemical purity (>95%) and molar activity (28.56-48.89 GBq/μmol). The affinity and specificity of tracers were assessed through cell uptake and docking experiments, demonstrating that [131I]I-NFIP exhibited high specificity for STING, with a cell-based IC50 value of 7.56 nM. Small-animal PET/SPECT imaging and biodistribution studies in tumor-bearing mice models were performed to verify the tracers' pharmacokinetics and tumor-targeting capabilities (n = 3/group). SPECT imaging demonstrated that [131I]I-NFIP rapidly accumulated in the Panc02 tumor quickly at 30 min post-injection, with a tumor-to-muscle (T/M) ratio of 2.03 ± 0.30. This ratio significantly decreased in the blocking group (1.10 ± 0.14, **P < 0.01, n = 3). Furthermore, tumor uptake and the T/M ratio of [131I]I-NFIP were positively associated with STING expression. In summary, [131I]I-NFIP is the first STING-specific inhibitor-based radioligand offering the potential for visualizing STING status in tumors.

Development of prognostic signatures and risk index related to lipid metabolism in ccRCC

Background

Clear cell renal cell carcinoma (ccRCC) is a metabolic disorder characterized by abnormal lipid accumulation in the cytoplasm. Lipid metabolism-related genes may have important clinical significance for prognosis prediction and individualized treatment.

Methods

We collected bulk and single-cell transcriptomic data of ccRCC and normal samples to identify key lipid metabolism-related prognostic signatures. qPCR was used to confirm the expression of signatures in cancer cell lines. Based on the identified signatures, we developed a lipid metabolism risk score (LMRS) as a risk index. We explored the potential application value of prognostic signatures and LMRS in precise treatment from multiple perspectives.

Results

Through comprehensive analysis, we identified five lipid metabolism-related prognostic signatures (ACADM, ACAT1, ECHS1, HPGD, DGKZ). We developed a risk index LMRS, which was significantly associated with poor prognosis in patients. There was a significant correlation between LMRS and the infiltration levels of multiple immune cells. Patients with high LMRS may be more likely to respond to immunotherapy. The different LMRS groups were suitable for different anticancer drug treatment regimens.

Conclusion

Prognostic signatures and LMRS we developed may be applied to the risk assessment of ccRCC patients, which may have potential guiding significance in the diagnosis and precise treatment of ccRCC patients.

Mechanistic insights into super-enhancer-related genes as prognostic signatures in colon cancer

BACKGROUND

Colon cancer (CC) is the most frequently occurring digestive system malignancy and is associated with a dismal prognosis. While super-enhancer (SE) genes have been identified as prognostic markers in several cancers, their potential as practical prognostic markers for CC patients remains unexplored.

METHODS

We obtained super-enhancer-related genes (SERGs) from the Human Super-Enhancer Database (SEdb). Transcriptome and relevant clinical data for colon cancer (CC) were sourced from the Gene Expression Omnibus (GEO) database. Subsequently, we identified up-regulated SERGs by the Weighted Gene Co-expression Network Analysis (WGCNA). Prognostic signatures were constructed via univariate and multivariate Cox regression analysis. We then delved into the mechanisms of these predictive genes by examining immune infiltration. We also assessed differential sensitivities to chemotherapeutic drugs between high- and low-SERGs risk patients. The critical gene was further validated using external datasets and finally confirmed by qRT PCR.

RESULTS

We established a ten-gene risk score prognostic model (S100A11, LZTS2, CYP2S1, ZNF552, PSMG1, GJC1, NXN, and DCBLD2), which can effectively predict patient survival rates. This model demonstrated effective prediction capabilities in survival rates at 1, 3, and 5 years and was successfully validated using external datasets. Furthermore, we detected significant differences in immune cell infiltration between high- and low-SERGs risk groups. Notably, high-risk patients exhibited heightened sensitivity to four chemotherapeutic agents, suggesting potential benefits for precision therapy in CC patients. Finally, qRT-PCR validation revealed a significant upregulation of LZTS2 mRNA expression in CC cells.

CONCLUSION

These findings reveal that the SERGs model could effectively predict the prognosis of CC.

Stabilizing Tumor-Resident Mast Cells Restores T-Cell Infiltration and Sensitizes Sarcomas to PD-L1 Inhibition

PURPOSE

To explore the cellular cross-talk of tumor-resident mast cells (MC) in controlling the activity of cancer-associated fibroblasts (CAF) to overcome tumor microenvironment (TME) abnormalities, enhancing the efficacy of immune-checkpoint inhibitors in sarcoma.

EXPERIMENTAL DESIGN

We used a coculture system followed by further validation in mouse models of fibrosarcoma and osteosarcoma with or without administration of the MC stabilizer and antihistamine ketotifen. To evaluate the contribution of ketotifen in sensitizing tumors to therapy, we performed combination studies with doxorubicin chemotherapy and anti-PD-L1 (B7-H1, clone 10F.9G2) treatment. We investigated the ability of ketotifen to modulate the TME in human sarcomas in the context of a repurposed phase II clinical trial.

RESULTS

Inhibition of MC activation with ketotifen successfully suppressed CAF proliferation and stiffness of the extracellular matrix accompanied by an increase in vessel perfusion in fibrosarcoma and osteosarcoma as indicated by ultrasound shear wave elastography imaging. The improved tissue oxygenation increased the efficacy of chemoimmunotherapy, supported by enhanced T-cell infiltration and acquisition of tumor antigen-specific memory. Importantly, the effect of ketotifen in reducing tumor stiffness was further validated in sarcoma patients, highlighting its translational potential.

CONCLUSIONS

Our study suggests the targeting of MCs with clinically administered drugs, such as antihistamines, as a promising approach to overcome resistance to immunotherapy in sarcomas.

Tumor-Infiltrating T Cells in Skin Basal Cell Carcinomas and Squamous Cell Carcinomas: Global Th1 Preponderance with Th17 Enrichment-A Cross-Sectional Study

Basal cell carcinomas (BCCs) and squamous cell carcinomas (SCCs) are high-incidence, non-melanoma skin cancers (NMSCs). The success of immune-targeted therapies in advanced NMSCs led us to anticipate that NMSCs harbored significant populations of tumor-infiltrating lymphocytes with potential anti-tumor activity. The main aim of this study was to characterize T cells infiltrating NMSCs. Flow cytometry and immunohistochemistry were used to assess, respectively, the proportions and densities of T cell subpopulations in BCCs (n = 118), SCCs (n = 33), and normal skin (NS, n = 30). CD8+ T cells, CD4+ T cell subsets, namely, Th1, Th2, Th17, Th9, and regulatory T cells (Tregs), CD8+ and CD4+ memory T cells, and γδ T cells were compared between NMSCs and NS samples. Remarkably, both BCCs and SCCs featured a significantly higher Th1/Th2 ratio (~four-fold) and an enrichment for Th17 cells. NMSCs also showed a significant enrichment for IFN-γ-producing CD8+T cells, and a depletion of γδ T cells. Using immunohistochemistry, NMSCs featured denser T cell infiltrates (CD4+, CD8+, and Tregs) than NS. Overall, these data favor a Th1-predominant response in BCCs and SCCs, providing support for immune-based treatments in NMSCs. Th17-mediated inflammation may play a role in the progression of NMSCs and thus become a potential therapeutic target in NMSCs.

The diagnostic value of selected immune parameters in peripheral blood of dogs with malignant mammary tumours - a preliminary study

Introduction

The main adaptive immune cells are T and B lymphocytes and they play key roles in the induction of immune responses against canine mammary tumours. Investigating these cell subpopulations may lead to more precise diagnosis of these malignancies.

Material and Methods

The percentages of CD3+, CD4+ and CD8+ T cells and of CD21+ B cells in the peripheral blood of bitches with malignant mammary tumours were compared with those in the blood of healthy animals. The phenotypic features of peripheral blood leukocytes were evaluated by flow cytometry.

Results

There was a significant difference in the mean percentages of CD3+ lymphocytes between healthy (66.7%) and metastatic dogs (46.1%), and between tumour-bearing non-metastatic (66.6%) and metastatic dogs. There was also a significant difference in CD4+ T helper cell percentages between healthy dogs (40.4%) and dogs with metastases (23.2%), and between the latter and dogs without them (35.5%). In the case of CD21+ lymphocyte subsets, a significant difference was noted between healthy animals (10.9%) and those with metastases (20.1%), and between the latter and patients without metastases (8.5%). There were also significant differences in CD3+/CD21+ ratios between the group with metastases (3.0), the healthy group (7.8), and the group without metastases (8.5). Similarly, a significant difference was noted in CD4+/CD8+ ratios between animals with metastases (1.4), bitches in the control group (2.2), and dogs without metastases (1.9).

Conclusion

Peripheral blood leukocyte phenotypic characteristics are putative novel biomarkers. These findings may be useful in future studies improving mammary tumour diagnostic procedures, especially in metastasis detection.

Treatment strategies and molecular mechanism of radiotherapy combined with immunotherapy in colorectal cancer

Radiotherapy (RT) remodels the tumor immune microenvironment (TIME) and modulates the immune response to indirectly destroy tumor cells, in addition to directly killing tumor cells. RT combined with immunotherapy may significantly enhance the efficacy of RT in colorectal cancer by modulating the microenvironment. However, the molecular mechanisms by which RT acts as an immunomodulator to modulate the immune microenvironment remain unclear. Further, the optimal modalities of RT combined with immunotherapy for the treatment of colorectal cancer, such as the time point of combining RT and immunization, the fractionation pattern and dosage of radiotherapy, and other methods to improve the efficacy, are also being explored parallelly. To address these aspects, in this review, we summarized the mechanisms by which RT modulates TIME and concluded the progress of RT combined with immunization in preclinical and clinical trials. Finally, we discussed heavy ion radiation therapy and the efficacy of prediction markers and other immune combination therapies. Overall, combining RT with immunotherapy to enhance antitumor effects will have a significant clinical implication and will help to facilitate individualized treatment modalities.

CELSR3 is a prognostic marker in HNSCC and correlates with immune cell infiltration in the tumor microenvironment

PURPOSE

To look at the diagnostic value of the CELSR receptor 3 (CELSR3) gene in head and neck squamous cell carcinoma (HNSCC) and its effect on tumor immune invasion, which is important for enhancing HNSCC treatment.

METHODS

Several bioinformatics tools were employed to investigate CELSR3's putative oncogenic pathway in HNSCC, and datasets from The Tumor Genome Atlas (TCGA), Tumor Immune Estimation Resource (TIMER), Gene Expression Profile Interaction Analysis (GEPIA) and LinkedOmics were extracted and evaluated. CELSR3 has been linked to tumor immune cell infiltration, immunological checkpoints, and immune-related genes. CELSR3's putative roles were investigated using Gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and pathway enrichment analysis. The expression level of CELSR3 in HNSCC tissues and cells was detected by RT-qPCR. The effects of CELSR3 on proliferation of HNSCC cells were detected by CCK-8 assay.

RESULTS

CELSR3 was shown to be expressed differently in different types of cancer and normal tissues. CELSR3 gene expression was linked to pN-stage and pM-stage. Patients with high CELSR3 expression also have a well prognosis. CELSR3 expression was found to be an independent predictive factor for HNSCC in both univariate and multivariate Cox regression analyses. We discovered the functional network of CELSR3 in HNSCC using GO and KEGG analysis. CELSR3 expression levels were found to be favorably associated with immune cell infiltration levels. Furthermore, CELSR3 expression levels were significantly correlated with the expression levels of many immune molecules, such as MHC genes, immune activation genes, chemokine receptors, and chemokines. CELSR3 is highly expressed in HNSCC tissues and cells. CELSR3 overexpression significantly inhibited the proliferation of HNSCC cells. CELSR3 expression may affect the immune microenvironment and, as a result, the prognosis of HNSCC.

CONCLUSION

CELSR3 expression is elevated in HNSCC tumor tissues, and high CELSR3 expression is associated with well prognosis, which inhibited the proliferation of NHSCC cells. CELSR3 has the potential to influence tumor formation by controlling tumor-infiltrating cells in the tumor microenvironment (TME). As a result, CELSR3 may have diagnostic significance in HNSCC.

Exploring the role of disulfidptosis-related signatures in immune microenvironment, prognosis and therapeutic strategies of cervical cancer

BACKGROUND

Cervical cancer is characterized by a complex immunosuppressive tumor microenvironment (TME). Disulfidptosis is a recently identified form of programmed cell death that has emerged as a crucial factor in tumorigenesis. However, the research on the specific involvement of disulfidptosis within the TME is still in its early stages.

METHODS

Under glucose starvation, SiHa and HeLa cells underwent experiments employing diverse cell death inhibitors and SLC7A11 knockdown to observe their impact on cell survival. TCGA-CESC cohort was subjected to consensus clustering for disulfidptosis-related clusters. Prognosis, function, immune infiltration, and differentially expressed genes (DEGs) evaluations among clusters were compared. A prognostic model based on DEGs and disulfidptosis regulator genes (DRGs) was constructed and internally and externally validated. The correlation between YWHAG and clinicopathological characteristics in cervical cancer patients was investigated at both the mRNA and protein levels. Proliferation and migration assays were performed to uncover the roles of YWHAG in cervical cancer.

RESULTS

Experimental validation confirmed disulfidptosis in cervical cancer cell lines. Cervical cancer patients were classified into three clusters based on DRGs, showing notably improved prognosis and increased immune infiltration in cluster B. The developed disulfidptosis-related prognostic model effectively stratified patients into high- and low-risk groups. Low-risk patients exhibited more favorable responses to immunotherapy and improved overall prognosis. Additionally, YWHAG, recognized as a tumor-promoting gene, demonstrated active roles in enhancing the growth, migration, and invasion of cervical cancer cells.

CONCLUSION

Our research proposed a prognostic model for cervical cancer, probably contributing to tumor microenvironment traits and more potent immunotherapy strategy exploration.

Identification of clinically relevant subsets CD39+PD-1+CD8+ T cells and CD39+ regulatory T cells in intrahepatic cholangiocarcinoma using single-cell CyTOF

Intrahepatic cholangiocarcinoma (iCCA) is an aggressive liver malignancy with limited treatment options and a dismal prognosis. The tumor immune microenvironment (TIME) is crucial for iCCA progression, yet its comprehensive characterization remains incomplete. This study utilized mass cytometry by time of flight (CyTOF) to comprehensively analyze immune cell populations in fresh iCCA tumor samples and adjacent peritumor liver tissues. Notably, NK cell percentages significantly decreased in iCCA lesions compared to peritumor liver tissues. Conversely, an enrichment of immunosuppressive CD39+Foxp3+CD4+ regulatory T cells (CD39+T-regs) and exhausted-like CD8+T cells (with pronounced CD39 and PD-1 expression) within TIME was identified and confirmed by multiplex immunofluorescence staining in an independent patient cohort (n = 140). Crucially, tumor-infiltrating CD39+T-regs and CD39+PD-1+CD8+T cells emerged as independent prognostic indicators associated with an unfavorable prognosis in iCCA. These findings unveil the intricate immune landscape within iCCA, offering valuable insights for disease management and novel cancer immunotherapies.

Unveiling HOXB7 as a novel diagnostic and prognostic biomarker through pan-cancer computer screening

We attempted to investigate the role of HOXB7 in tumor progression and evolution by means of an extensive computer screening analysis of various cancer types. We performed univariate Cox regression and Kaplan-Meier survival analyses to assess the impact of HOXB7 on overall survival (OS), disease-specific survival (DSS), and progression-free interval (PFI) in different types of cancer. Furthermore, we examined the relationship between HOXB7 and several clinical features: tumor microenvironment, immune regulatory genes, immune checkpoints, tumor mutational burden (TMB), and microsatellite instability (MSI). We performed gene set enrichment analysis to gain deeper insights into the potential molecular mechanisms of HOXB7, and validated our findings through functional assays in cells, including methyl thiazolyl tetrazolium cytotoxicity and Transwell invasion assays. HOXB7 expression was associated with different clinical characteristics in numerous malignancies. Higher HOXB7 expression was associated with worse OS, DSS, and PFI in some cancer types. In particular, HOXB7 expression was favorably associated with immune cell infiltration, immune regulatory genes, immunological checkpoints, TMB, and MSI in malignancies. Furthermore, we identified a strong link between copper death-associated gene expression and HOXB7 expression. According to the findings of this study, HOXB7 might serve as an appealing focus for tumor diagnosis and immunotherapy and a prospective indicator of prognosis.

Allogeneic chimeric antigen receptor T cells for children with relapsed/refractory B-cell precursor acute lymphoblastic leukemia

Chimeric antigen receptor (CAR) T-cell therapy has emerged as a breakthrough cancer therapy over the past decade. Remarkable outcomes in B-cell lymphoproliferative disorders and multiple myeloma have been reported in both pivotal trials and real-word studies. Traditionally, the use of a patient's own (autologous) T cells to manufacture CAR products has been the standard practice. Nevertheless, this approach has some drawbacks, including manufacturing delays, dependence on the functional fitness of the patient's T cells, which can be compromised by both the disease and prior therapies, and contamination of the product with blasts. A promising alternative is offered by the development of allogeneic CAR-cell products. This approach has the potential to yield more efficient drug products and enables the use of effector cells with negligible alloreactive potential and a significant CAR-independent antitumor activity through their innate receptors (i.e., natural killer cells, γδ T cells and cytokine induced killer cells). In addition, recent advances in genome editing tools offer the potential to overcome the primary challenges associated with allogeneic CAR T-cell products, namely graft-versus-host disease and host allo-rejection, generating universal, off-the-shelf products. In this review, we summarize the current pre-clinical and clinical approaches based on allogeneic CAR T cells, as well as on alternative effector cells, which represent exciting opportunities for multivalent approaches and optimized antitumor activity.

Histone Lactylation Drives CD8 T Cell Metabolism and Function

The activation and functional differentiation of CD8 T cells are linked to metabolic pathways that result in the production of lactate. Lactylation is a lactate-derived histone post-translational modification (hPTM); however, the relevance of histone lactylation in the context of CD8 T cell activation and function is not known. Here, we show the enrichment of H3K18-lactylation (H3K18la) and H3K9-lactylation (H3K9la) in human and murine CD8 T cells which act as transcription initiators of key genes regulating CD8 T cell phenotype and function. Further, we note distinct impacts of H3K18la and H3K9la on CD8 T cell subsets linked to their specific metabolic profiles. Importantly, we demonstrate that modulation of H3K18la and H3K9la by targeting metabolic and epigenetic pathways regulates CD8 T cell effector function including anti-tumor immunity in preclinical models. Overall, our study uncovers the unique contributions of H3K18la and H3K9la in modulating CD8 T cell phenotype and function intricately associated with metabolic state.

T cell exhaustion initiates tertiary lymphoid structures and turbocharges cancer-immunity cycle

Immune therapies represented by immune checkpoint blockade (ICB) have significantly transformed cancer treatment. However, the effectiveness of these treatments depends on the status of T cells. T cell exhaustion, characterized by diminished effector function, increased expression of co-inhibitory receptors, and clonal deletion, emerges as a hypofunctional state resulting from chronic exposure to antigens, posing an obstacle to ICB therapy. Several studies have deeply explored T cell exhaustion, providing innovative insights and correlating T cell exhaustion with tertiary lymphoid structures (TLS) formation. TLS, lymphocyte aggregates formed in non-lymphoid tissues amid chronic inflammation, serve as pivotal reservoirs for anti-tumour immunity. Here, we underscore the pivotal role of T cell exhaustion as a signalling mechanism in reinvigorating anti-tumour immunity by turbocharging cancer-immunity (CI) cycle, particularly when tumour becomes unmanageable. Building upon this concept, we summarize emerging immunotherapeutic strategies aimed at enhancing the response rate to ICB therapy and improving patient prognosis.

Revolutionizing tumor immunotherapy: unleashing the power of progenitor exhausted T cells

In exploring persistent infections and malignancies, a distinctive subgroup of CD8+ T cells, progenitor exhausted CD8+ T (Tpex) cells, has been identified. These Tpex cells are notable for their remarkable self-renewal and rapid proliferation abilities. Recent strides in immunotherapy have demonstrated that Tpex cells expand and differentiate into responsive exhausted CD8+ T cells, thus underscoring their critical role in the immunotherapeutic retort. Clinical examinations have further clarified a robust positive correlation between the proportional abundance of Tpex cells and enhanced clinical prognosis. Tpex cells have found noteworthy applications in the formulation of inventive immunotherapeutic approaches against tumors. This review describes the functions of Tpex cells in the tumor milieu, particularly their potential utility in tumor immunotherapy. Precisely directing Tpex cells may be essential to achieving successful outcomes in immunotherapy against tumors.

Identification of the CD8+ T-cell Related Signature for Predicting the Prognosis of Gastric Cancer Based on Integrated Analysis of Bulk and Single-cell RNA Sequencing Data

The infiltration of CD8+ T cells in the tumor microenvironment is associated with better survival and immunotherapy response. However, their roles in gastric cancer have not been explored so far. In here, the profiles of GC gene expression were collected from The Cancer Genome Atlas database. Single-cell transcriptomic data originated from GSE134520. Cell clustering, annotation, and CD8+ T-cell differential genes were from the TISCH database. We determined 896 CD8+ T-cell differential genes by scRNA-seq analysis. After integrating immune-related genes, 174 overlapping genes were obtained and a novel risk model was subsequently built. The performance of CD8+ T-cell-associated gene signature was assessed in the training and external validation sets. The gene signature showed independent risk factors of overall survival for GC. A quantitative nomogram was built to enhance the clinical efficacy of this signature. Furthermore, low-risk individuals showed higher mutation status, higher immune checkpoint expression, low Tumour Immune Dysfunction and Exclusion (TIDE) scores, and higher IPS-PD-1 combined IPS-CTLA4 scores, indicating a greater response to immunotherapy. In addition, analysis of IMvigor210 immunotherapy cohort demonstrated that low-risk individuals had a favorable response to prognosis and immunotherapy. In conclusion, we generated a CD8+ T-cell-related signature that can serve as a promising tool for personalized prognosis prediction and guiding decisions regarding immunotherapy in GC patients.

Apoptosis, a Metabolic "Head-to-Head" between Tumor and T Cells: Implications for Immunotherapy

Induction of apoptosis represents a promising therapeutic approach to drive tumor cells to death. However, this poses challenges due to the intricate nature of cancer biology and the mechanisms employed by cancer cells to survive and escape immune surveillance. Furthermore, molecules released from apoptotic cells and phagocytes in the tumor microenvironment (TME) can facilitate cancer progression and immune evasion. Apoptosis is also a pivotal mechanism in modulating the strength and duration of anti-tumor T-cell responses. Combined strategies including molecular targeting of apoptosis, promoting immunogenic cell death, modulating immunosuppressive cells, and affecting energy pathways can potentially overcome resistance and enhance therapeutic outcomes. Thus, an effective approach for targeting apoptosis within the TME should delicately balance the selective induction of apoptosis in tumor cells, while safeguarding survival, metabolic changes, and functionality of T cells targeting crucial molecular pathways involved in T-cell apoptosis regulation. Enhancing the persistence and effectiveness of T cells may bolster a more resilient and enduring anti-tumor immune response, ultimately advancing therapeutic outcomes in cancer treatment. This review delves into the pivotal topics of this multifaceted issue and suggests drugs and druggable targets for possible combined therapies.

Immune cell patterns before and after neoadjuvant immune checkpoint blockade combined with chemoradiotherapy in locally advanced esophageal squamous cell carcinoma

BACKGROUND

Neoadjuvant immune checkpoint blockade (ICB) combined with chemoradiotherapy offers high pathologic complete response (pCR) rate for patients with locally advanced esophageal squamous cell carcinomas (ESCC). But the dynamic tumor immune microenvironment modulated by such neoadjuvant therapy remains unclear.

PATIENTS AND METHODS

A total of 41 patients with locally advanced ESCC were recruited. All patients received neoadjuvant toripalimab combined with concurrent chemoradiotherapy. Matched pre- and post-treatment tissues were obtained for fluorescent multiplex immunohistochemistry (mIHC) and IHC analyses. The densities and spatial distributions of immune cells were determined by HALO modules. The differences of immune cell patterns before and after neoadjuvant treatment were investigated.

RESULTS

In the pre-treatment tissues, more stromal CD3 + FoxP3 + Tregs and CD86+/CD163 + macrophages were observed in patients with residual tumor existed in the resected lymph nodes (pN1), compared with patients with pCR. The majority of macrophages were distributed in close proximity to tumor nest in pN1 patients. In the post-treatment tissues, pCR patients had less CD86 + cell infiltration, whereas higher CD86 + cell density was significantly associated with higher tumor regression grades (TRG) in non-pCR patients. When comparing the paired pre- and post-treatment samples, heterogeneous therapy-associated immune cell patterns were found. Upon to the treatment, CD3 + T lymphocytes were slightly increased in pCR patients, but markedly decreased in non-pCR patients. In contrast, a noticeable increase and a less obvious decrease of CD86 + cell infiltration were respectively depicted in non-pCR and pCR patients. Furthermore, opposite trends of the treatment-induced alterations of CD8 + and CD15 + cell infiltrations were observed between pN0 and pN1 patients.

CONCLUSIONS

Collectively, our data demonstrate a comprehensive picture of tumor immune landscape before and after neoadjuvant ICB combined with chemoradiotherapy in ESCC. The infiltration of CD86 + macrophage may serve as an unfavorable indicator for neoadjuvant toripalimab combined with chemoradiotherapy.

Immune Regulation and Immune Therapy in Melanoma: Review with Emphasis on CD155 Signalling

Melanoma is commonly diagnosed in a younger population than most other solid malignancies and, in Australia and most of the world, is the leading cause of skin-cancer-related death. Melanoma is a cancer type with high immunogenicity; thus, immunotherapies are used as first-line treatment for advanced melanoma patients. Although immunotherapies are working well, not all the patients are benefitting from them. A lack of a comprehensive understanding of immune regulation in the melanoma tumour microenvironment is a major challenge of patient stratification. Overexpression of CD155 has been reported as a key factor in melanoma immune regulation for the development of therapy resistance. A more thorough understanding of the actions of current immunotherapy strategies, their effects on immune cell subsets, and the roles that CD155 plays are essential for a rational design of novel targets of anti-cancer immunotherapies. In this review, we comprehensively discuss current anti-melanoma immunotherapy strategies and the immune response contribution of different cell lineages, including tumour endothelial cells, myeloid-derived suppressor cells, cytotoxic T cells, cancer-associated fibroblast, and nature killer cells. Finally, we explore the impact of CD155 and its receptors DNAM-1, TIGIT, and CD96 on immune cells, especially in the context of the melanoma tumour microenvironment and anti-cancer immunotherapies.

Netrin G1 Ligand is a new stromal immunomodulator that promotes pancreatic cancer

Understanding pancreatic cancer biology is fundamental for identifying new targets and for developing more effective therapies. In particular, the contribution of the stromal microenvironment to pancreatic cancer tumorigenesis requires further exploration. Here, we report the stromal roles of the synaptic protein Netrin G1 Ligand (NGL-1) in pancreatic cancer, uncovering its pro-tumor functions in cancer-associated fibroblasts and in immune cells. We observed that the stromal expression of NGL-1 inversely correlated with patients' overall survival. Moreover, germline knockout (KO) mice for NGL-1 presented decreased tumor burden, with a microenvironment that is less supportive of tumor growth. Of note, tumors from NGL-1 KO mice produced less immunosuppressive cytokines and displayed an increased percentage of CD8 + T cells than those from control mice, while preserving the physical structure of the tumor microenvironment. These effects were shown to be mediated by NGL-1 in both immune cells and in the local stroma, in a TGF-β-dependent manner. While myeloid cells lacking NGL-1 decreased the production of immunosuppressive cytokines, NGL-1 KO T cells showed increased proliferation rates and overall polyfunctionality compared to control T cells. CAFs lacking NGL-1 were less immunosuppressive than controls, with overall decreased production of pro-tumor cytokines and compromised ability to inhibit CD8 + T cells activation. Mechanistically, these CAFs downregulated components of the TGF-β pathway, AP-1 and NFAT transcription factor families, resulting in a less tumor-supportive phenotype. Finally, targeting NGL-1 genetically or using a functionally antagonistic small peptide phenocopied the effects of chemotherapy, while modulating the immunosuppressive tumor microenvironment (TME), rather than eliminating it. We propose NGL-1 as a new local stroma and immunomodulatory molecule, with pro-tumor roles in pancreatic cancer.

Statement of Significance

Here we uncovered the pro-tumor roles of the synaptic protein NGL-1 in the tumor microenvironment of pancreatic cancer, defining a new target that simultaneously modulates tumor cell, fibroblast, and immune cell functions. This study reports a new pathway where NGL-1 controls TGF-β, AP-1 transcription factor members and NFAT1, modulating the immunosuppressive microenvironment in pancreatic cancer. Our findings highlight NGL-1 as a new stromal immunomodulator in pancreatic cancer.

The diversity of inhibitory receptor co-expression patterns of exhausted CD8+ T cells in oropharyngeal carcinoma

Exhausted CD8+ T cells (Texs) are characterized by the expression of various inhibitory receptors (IRs), whereas the functional attributes of these co-expressed IRs remain limited. Here, we systematically characterized the diversity of IR co-expression patterns in Texs from both human oropharyngeal squamous cell carcinoma (OPSCC) tissues and syngeneic OPSCC model. Nearly 60% of the Texs population co-expressed two or more IRs, and the number of co-expressed IRs was positively associated with superior exhaustion and cytotoxicity phenotypes. In OPSCC patients, programmed cell death-1 (PD-1) blockade significantly enhanced PDCD1-based co-expression with other IR genes, whereas dual blockades of PD-1 and cytotoxic T lymphocyte-associated protein 4 (CTLA-4) significantly upregulated CTLA4-based co-expression with other IR genes. Collectively, our findings demonstrate that highly diverse IR co-expression is a leading feature of Texs and represents their functional states, which might provide essential clues for the rational selection of immune checkpoint inhibitors in treating OPSCC.

LRIG1 engages ligand VISTA and impairs tumor-specific CD8+ T cell responses

Immune checkpoint blockade is a promising approach to activate antitumor immunity and improve the survival of patients with cancer. V-domain immunoglobulin suppressor of T cell activation (VISTA) is an immune checkpoint target; however, the downstream signaling mechanisms are elusive. Here, we identify leucine-rich repeats and immunoglobulin-like domains 1 (LRIG1) as a VISTA binding partner, which acts as an inhibitory receptor by engaging VISTA and suppressing T cell receptor signaling pathways. Mice with T cell-specific LRIG1 deletion developed superior antitumor responses because of expansion of tumor-specific cytotoxic T lymphocytes (CTLs) with increased effector function and survival. Sustained tumor control was associated with a reduction of quiescent CTLs (TCF1+ CD62Lhi PD-1low) and a reciprocal increase in progenitor and memory-like CTLs (TCF1+ PD-1+). In patients with melanoma, elevated LRIG1 expression on tumor-infiltrating CD8+ CTLs correlated with resistance to immunotherapies. These results delineate the role of LRIG1 as an inhibitory immune checkpoint receptor and propose a rationale for targeting the VISTA/LRIG1 axis for cancer immunotherapy.

Upregulation of GOLPH3 mediated by Bisphenol a promotes colorectal cancer proliferation and migration: evidence based on integrated analysis

Background

The interaction between environmental endocrine-disrupting chemicals, such as Bisphenol A (BPA), and their influence on cancer progression, particularly regarding the GOLPH3 gene in colorectal cancer, remains unclear.

Methods

We performed an integrated analysis of transcriptional profiling, clinical data, and bioinformatics analyses utilizing data from the Comparative Toxicogenomics Database and The Cancer Genome Atlas. The study employed ClueGO, Gene Set Enrichment Analysis, and Gene Set Variation Analysis for functional enrichment analysis, alongside experimental assays to examine the effects of BPA exposure on colorectal cancer cell lines, focusing on GOLPH3 expression and its implications for cancer progression.

Results

Our findings demonstrated that BPA exposure significantly promoted the progression of colorectal cancer by upregulating GOLPH3, which in turn enhanced the malignant phenotype of colorectal cancer cells. Comparative analysis revealed elevated GOLPH3 protein levels in cancerous tissues versus normal tissues, with single-cell analysis indicating widespread GOLPH3 presence across various cell types in the cancer microenvironment. GOLPH3 was also associated with multiple carcinogenic pathways, including the G2M checkpoint. Furthermore, our investigation into the colorectal cancer microenvironment and genomic mutation signature underscored the oncogenic potential of GOLPH3, exacerbated by BPA exposure.

Conclusion

This study provides novel insights into the complex interactions between BPA exposure and GOLPH3 in the context of colorectal cancer, emphasizing the need for heightened awareness and measures to mitigate BPA exposure risks. Our findings advocate for further research to validate these observations in clinical and epidemiological settings and explore potential therapeutic targets within these pathways.

The cell cycle regulator p16 promotes tumor infiltrated CD8+ T cell exhaustion and apoptosis

The therapeutic efficacy of adoptive T cell therapy is largely restricted by reduced viability and dysfunction of CD8+ T cells. Continuous antigen stimulation disrupts the expansion, effector function, and metabolic fitness of CD8+ T cells, leading to their differentiation into an exhausted state within the tumor microenvironment (TME). While the function of the cell cycle negative regulator p16 in senescent cells is well understood, its role in T cell exhaustion remains unclear. In this study, we demonstrated that TCR stimulation of CD8+ T cells rapidly upregulates p16 expression, with its levels positively correlating with TCR affinity. Chronic TCR stimulation further increased p16 expression, leading to CD8+ T cell apoptosis and exhaustion differentiation, without inducing DNA damage or cell senescence. Mechanistic investigations revealed that p16 downregulates mTOR, glycolysis, and oxidative phosphorylation (OXPHOS) associated gene expression, resulting in impaired mitochondrial fitness, reduced T cell viability, and diminished effector function. Furthermore, the deletion of p16 significantly enhances the persistence of CD8+ T cells within tumors and suppresses the terminal exhaustion of tumor-infiltrating T cells. Overall, our findings elucidate how increased p16 expression reshapes T cell intracellular metabolism, drives T cell apoptosis and exhaustion differentiation, and ultimately impairs T cell anti-tumor function.

Tumor-neutrophil cross talk orchestrates the tumor microenvironment to determine the bladder cancer progression

The immune landscape of bladder cancer progression is not fully understood, and effective therapies are lacking in advanced bladder cancer. Here, we visualized that bladder cancer cells recruited neutrophils by secreting interleukin-8 (IL-8); in turn, neutrophils played dual functions in bladder cancer, including hepatocyte growth factor (HGF) release and CCL3highPD-L1high super-immunosuppressive subset formation. Mechanistically, c-Fos was identified as the mediator of HGF up-regulating IL-8 transcription in bladder cancer cells, which was central to the positive feedback of neutrophil recruitment. Clinically, compared with serum IL-8, urine IL-8 was a better biomarker for bladder cancer prognosis and clinical benefit of immune checkpoint blockade (ICB). Additionally, targeting neutrophils or hepatocyte growth factor receptor (MET) signaling combined with ICB inhibited bladder cancer progression and boosted the antitumor effect of CD8+ T cells in mice. These findings reveal the mechanism by which tumor-neutrophil cross talk orchestrates the bladder cancer microenvironment and provide combination strategies, which may have broad impacts on patients suffering from malignancies enriched with neutrophils.

Single-cell sequencing of tumour infiltrating T cells efficiently identifies tumour-specific T cell receptors based on the T cell activation score

Adoptively transferred T cell receptor-engineered T cells are a promising cancer treatment strategy, and the identification of tumour-specific TCRs is essential. Previous studies reported that tumour-reactive T cells and TCRs could be isolated based on the expression of activation markers. However, since T cells with different cell states could not respond uniformly to activation but show a heterogeneous expression profile of activation and effector molecules, isolation of tumour-reactive T cells based on single activation or effector molecules could result in the absence of tumour-reactive T cells; thus, combinations of multiple activation and effector molecules could improve the efficiency of isolating tumour-specific TCRs. We enrolled two patients with lung adenocarcinoma and obtained their tumour infiltrating lymphocytes (TILs) and autologous tumour cells (ATCs). TILs were cocultured with the corresponding ATCs for 12 h and subjected to single-cell RNA sequencing. First, we identified three TCRs with the highest expression levels of IFNG and TNFRSF9 mRNA for each patient, yet only the top one or two recognized the corresponding ATCs in each patient. Next, we defined the activation score based on normalized expression levels of IFNG, IL2, TNF, IL2RA, CD69, TNFRSF9, GZMB, GZMA, GZMK, and PRF1 mRNA for each T cell and then identified three TCRs with the highest activation score for each patient. We found that all three TCRs in each patient could specifically identify corresponding ATCs. In conclusion, we established an efficient approach to isolate tumour-reactive TCRs based on combinations of multiple activation and effector molecules through single-cell RNA sequencing.

Single-cell analysis of anti-BCMA CAR T cell therapy in patients with central nervous system autoimmunity

Chimeric antigen receptor (CAR) T cell immunotherapy for the treatment of neurological autoimmune diseases is promising, but CAR T cell kinetics and immune alterations after treatment are poorly understood. Here, we performed single-cell multi-omics sequencing of paired cerebrospinal fluid (CSF) and blood samples from patients with neuromyelitis optica spectrum disorder (NMOSD) treated with anti-B cell maturation antigen (BCMA) CAR T cells. Proliferating cytotoxic-like CD8+ CAR T cell clones were identified as the main effectors in autoimmunity. Anti-BCMA CAR T cells with enhanced features of chemotaxis efficiently crossed the blood-CSF barrier, eliminated plasmablasts and plasma cells in the CSF, and suppressed neuroinflammation. The CD44-expressing early memory phenotype in infusion products was potentially associated with CAR T cell persistence in autoimmunity. Moreover, CAR T cells from patients with NMOSD displayed distinctive features of suppressed cytotoxicity compared with those from hematological malignancies. Thus, we provide mechanistic insights into CAR T cell function in patients with neurological autoimmune disease.

Identification of clinically relevant T cell receptors for personalized T cell therapy using combinatorial algorithms

A central challenge in developing personalized cancer cell immunotherapy is the identification of tumor-reactive T cell receptors (TCRs). By exploiting the distinct transcriptomic profile of tumor-reactive T cells relative to bystander cells, we build and benchmark TRTpred, an antigen-agnostic in silico predictor of tumor-reactive TCRs. We integrate TRTpred with an avidity predictor to derive a combinatorial algorithm of clinically relevant TCRs for personalized T cell therapy and benchmark it in patient-derived xenografts.