Distinct role of antigen-specific T helper type 1 (Th1) and Th2 cells in tumor eradication in vivo

A Tc1- and Th1-T-lymphocyte-rich tumor microenvironment is a hallmark of MSI colorectal cancer

Microsatellite instability is a strong predictor of response to immune checkpoint therapy and patient outcome in colorectal cancer. Although enrichment of distinct T-cell subpopulations has been determined to impact the response to immune checkpoint therapy and patient outcome, little is known about the underlying changes in the composition of the immune tumor microenvironment. To assess the density, composition, degree of functional marker expression, and spatial interplay of T-cell subpopulations, 79 microsatellite instable (MSI) and 1,045 microsatellite stable (MSS) colorectal cancers were analyzed. A tissue microarray and large sections were stained with 19 antibodies directed against T cells, antigen-presenting cells, functional markers, and structural proteins using our BLEACH&STAIN multiplex-fluorescence immunohistochemistry approach. A deep learning-based framework comprising >20 different convolutional neuronal networks was developed for image analysis. The composition of Type 1 (T-bet+), Type 2 (GATA3+), Type 17 (RORγT+), NKT-like (CD56+), regulatory (FOXP3+), follicular (BCL6+), and cytotoxic (CD3+CD8+) or helper (CD3+CD4+) T cells showed marked differences between MSI and MSS patients. For instance, the fraction of Tc1 and Th1 was significantly higher (p < 0.001 each), while the fraction of Tregs, Th2, and Th17 T cells was significantly lower (p < 0.05) in MSI compared to MSS patients. The degree of TIM3, CTLA-4, and PD-1 expression on most T-cell subpopulations was significantly higher in MSI compared to MSS patients (p < 0.05 each). Spatial analysis revealed increased interactions between Th1, Tc1, and dendritic cells in MSI patients, while in MSS patients the strongest interactions were found between Tregs, Th17, Th2, and dendritic cells. The additional analysis of 12 large sections revealed a divergent immune composition at the invasive margin. In summary, this study identified a higher fraction of Tc1 and Th1 T cells accompanied by a paucity of regulatory T-cell, Th17, and Th2 T-cell subpopulations, along with a distinct interaction profile, as a hallmark of MSI compared to MSS colorectal cancers. © 2025 The Author(s). The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

Development of a nano-vaccine for high-grade serous ovarian cancer

High-Grade Serous Carcinoma (HGSC) is characterised by aggressive malignant tumours and poor prognosis accounting for 75% of ovarian cancer. Conventional treatments often result in relapse, with a need for innovative therapeutic approaches. This study aimed to develop and evaluate a DNA vaccine targeting the preferentially expressed antigen of melanoma, PRAME, a cancer tumour antigen (CTA) overexpressed in HGSC. PRAME demonstrated the highest differential gene expression between normal fallopian tubes and HGSC tumour tissues in a range of patient datasets. The PRAME DNA was condensed by the cationic cell-penetrating peptide RALA to form nanoparticles (NPs). These self-assembling NPs exhibited a mean hydrodynamic size <150 nm and zeta potential >10 mV at N : P ratios ≥4 with ≤3% free DNA. The NPs successfully transfected NCTC-929 and DC 2.4 cells with PRAME overexpression, with negligible cytotoxicity. Vaccination with the NPs in vivo elevated CD4+ and CD8+ T-cell activation with increased expression of INF-γ and IL-2 cytokines. Vaccination also significantly improved survival rates in a PRAME-expressing tumour model in vivo. This study demonstrated the utility of a PRAME-targeted DNA vaccine for HGSC treatment which warrants further investigation.

Selective H2-O tissue expression reduces risk for graft-versus-host disease in an in vivo transplantation model

BACKGROUND

Allogeneic stem cell transplantation (aSCT) is frequently used to treat patients with hematological malignancies. The therapeutic effect relies mainly on the graft-versus-leukemia (GvL) effect, in which donor T-cells eliminate residual malignant cells. Unfortunately, the beneficial GvL is often accompanied by detrimental graft-versus-host disease (GvHD). A successful separation of both effects could not yet be achieved. In previous work, we identified two groups of HLA-class II restricted antigens depending on their behavior towards HLA-DM. DM-resistant antigens are presented in the presence of HLA-DM, whereas presentation of DM-sensitive antigens relies on the inhibitory molecule HLA-DO. Due to the unique expression pattern of HLA-DO, DM sensitive antigens cannot be presented efficiently by non-hematopoietic cells even under inflammatory conditions. This suggests that CD4+ T-cells directed against DM-sensitive antigens may be able to separate GvL from GvHD.

OBJECTIVE

In this study, we wanted to demonstrate convincingly that HLA-DO expression strongly influences the severity of GvHD in allogeneic stem cell transplantation.

METHODS

Therefore, we generated a modified CD4 donor lymphocyte infusion (DLI) depleted of CD4+ T-cells directed against DM resistant antigens to address its potential to induce GvHD in an in vivo MHC mismatch transplantation model in dependency on selective tissue expression of H2-O using H2-O wildtype, knockout and transgenic recipients.

RESULTS

Intriguingly, we could demonstrate that our modified CD4 DLI targeting DM-sensitive antigens only induced mild GvHD in wildtype recipients with endogenous selective H2-O expression and none in H2-O knockouts, while assessing the immunogenic potential of DM-sensitive antigens in H2-O transgenic recipients.

CONCLUSION

The results of the present work provide evidence that DM-resistant antigens are main targets of GvHD and addressing DM-sensitive antigens might be a promising tool to improve outcome after aSCT by separating GvL from GvHD.

Low type-2 immune effectors modulate atopic diseases' protective role in pancreatic cancer risk

Studies reported that atopic individuals exhibit a 36% reduced risk of developing pancreatic ductal adenocarcinoma (PDAC); however, the underlying molecular mechanisms remain unclear. This study examines the specific role of type-2 immune response in the atopy-PDAC inverse association. To endotype atopic conditions using type-2 immune effectors (i.e., eosinophils and immunoglobulin-E[IgE]) and investigate their protective effect against PDAC risk, IgE levels were measured in 688 PDAC cases and 558 controls from the PanGenEU case-control study. 'IgE-sensitization' was defined as having >100 kU/L total IgE with lab-tested sensitization to ≥1 food- or aeroallergens. Atopic conditions were determined using the European Community Respiratory Health Survey questionnaire. The UK Biobank cohort's 544 PDAC cases and 92,038 nested controls were categorized based on a threshold of 0.15 × 109 eosinophil cells/L plus self-reported atopy. Odds ratios (ORs) with 95% confidence intervals (CIs) were estimated using multivariable logistic regression. Restricted cubic splines were applied to examine the nonlinear relationship between type-2 immune effectors and PDAC risk. PDAC risk was not linearly associated with type-2 immune effectors levels. Compared to low IgE-sensitized non-atopic individuals, the low IgE-sensitized atopic population had significantly reduced PDAC risk (OR = 0.56, 95% CI: 0.35-0.84). Similar trends were observed among atopic individuals with low eosinophil counts (OR = 0.67, 95% CI: 0.47-0.95). Atopic conditions were inversely associated with PDAC risk, particularly among those with low levels of type-2 immune effectors. This indicates the protective effect of atopy against PDAC risk is modulated by low type-2 immune response.

Levental K, Leen AM, Mamonkin M, Carisey A, Varadarajan N, Hegde M, Joseph SK, Levental I, Mukherjee M, Ahmed N. Molecular dynamics at immune synapse lipid rafts influence the cytolytic behavior of CAR T cells

Chimeric antigen receptor T cells (CART) targeting CD19 through CD28.ζ signaling induce rapid lysis of leukemic blasts, contrasting with persistent tumor control exhibited by 4-1BB.ζ-CART. We reasoned that molecular dynamics at the CART immune synapse (CARIS) could explain differences in their tumor rejection kinetics. We observed that CD28.ζ-CART engaged in brief highly lethal CARIS and mastered serial killing, whereas 4-1BB.ζ-CART formed lengthy CARIS and relied on robust expansion and cooperative killing. We analyzed CARIS membrane lipid rafts (mLRs) and found that, upon tumor engagement, CD28.ζ-CAR molecules rapidly but transiently translocated into mLRs, mobilizing the microtubular organizing center and lytic granules to the CARIS. This enabled fast CART recovery and sensitivity to low target site density. In contrast, gradual accumulation of 4-1BB.ζ-CAR and LFA-1 molecules at mLRs built mechanically tonic CARIS mediating chronic Fas ligand-based killing. The differences in CD28.ζ- and 4-1BB.ζ-CARIS dynamics explain the distinct cytolytic behavior of CART and can guide engineering of more adaptive effective cellular products.

Prognostic role of tumor-infiltrating lymphocytes in gastric cancer: A systematic review and meta-analysis

BACKGROUND

To analyze the relationship between tumor-infiltrating lymphocytes (TILs) subtypes and infiltration locations and the prognosis of gastric cancer (GC) patients.

METHODS

Eligible articles were obtained through systematic retrieval and rigorous screening, collecting study information and extracting hazard ratio (HR), 95 % confidence interval (CI) for pooled analyses of disease-free survival (DFS) and overall survival (OS).

RESULTS

Higher CD4+ TILs were correlated with favorable OS (HR=0.79, 95 %CI: 0.66-0.94, P = 0.009), the similar results were observed in tumor center and in infiltration margin. Higher CD8+ TILs prolonged DFS (HR=0.69, 95 %CI: 0.51-0.95, P = 0.02) and OS (HR=0.96, 95 %CI: 0.94-0.99, P = 0.006); For OS, tumor center and infiltration margin groups showed positive results. Neither the overall analysis nor the subgroup analyses indicated that the level of FOXP3+ TILs was associated with prognosis (DFS: HR=0.89, 95 %CI: 0.66-1.19, P = 0.42; OS: HR=0.98, 95 %CI: 0.85-1.13, P = 0.75). Pooled results revealed that higher CD3+ TILs were correlated with favorable DFS (HR=0.69, 95 %CI: 0.56-0.84, P = 0.0003) but not OS (HR=1.00, 95 %CI: 0.99-1.01, P = 0.48).

CONCLUSIONS

High infiltrating CD3+, CD4+, CD8+ T cells prolong survival, and FOXP3+ subset is not related to prognosis in GC. For CD4+ and CD8+, positive correlations between the infiltration level and OS were present in tumor center and infiltration margin groups.

Reinventing type 2 immunity in cancer

Our understanding of type 2 immunity has undergone a substantial transformation in recent years, revealing previously unknown functions. Beyond its canonical role in defence against parasitic helminth infections, type 2 immunity safeguards the host through additional mechanisms, including the suppression of excessive type 1 immune responses, regulation of tissue repair and maintenance of adipose tissue homeostasis. However, unlike type 1 immune responses, type 2 immunity is perceived as a potential promoter of tumorigenesis. Emerging evidence challenges this perspective, painting a more nuanced picture in which type 2 immunity might protect against or even actively suppress tumour growth and progression. In this Review, we explore discoveries that highlight the potential of type 2 immunity in reshaping the landscape of cancer immunotherapies.

Engineered mitochondria exert potent antitumor immunity as a cancer vaccine platform

The preferable antigen delivery profile accompanied by sufficient adjuvants favors vaccine efficiency. Mitochondria, which feature prokaryotic characteristics and contain various damage-associated molecular patterns (DAMPs), are easily taken up by phagocytes and simultaneously activate innate immunity. In the current study, we established a mitochondria engineering platform for generating antigen-enriched mitochondria as cancer vaccine. Ovalbumin (OVA) and tyrosinase-related protein 2 (TRP2) were used as model antigens to synthesize fusion proteins with mitochondria-localized signal peptides. The lentiviral infection system was then employed to produce mitochondrial vaccines containing either OVA or TRP2. Engineered OVA- and TRP2-containing mitochondria (OVA-MITO and TRP2-MITO) were extracted and evaluated as potential cancer vaccines. Impressively, the engineered mitochondria vaccine demonstrated efficient antitumor effects when used as both prophylactic and therapeutic vaccines in murine tumor models. Mechanistically, OVA-MITO and TRP2-MITO potently recruited and activated dendritic cells (DCs) and induced a tumor-specific cell-mediated immunity. Moreover, DC activation by mitochondria vaccine critically involves TLR2 pathway and its lipid agonist, namely, cardiolipin derived from the mitochondrial membrane. The results demonstrated that engineered mitochondria are natively well-orchestrated carriers full of immune stimulants for antigen delivery, which could preferably target local dendritic cells and exert strong adaptive cellular immunity. This proof-of-concept study established a universal platform for vaccine construction with engineered mitochondria bearing alterable antigens for cancers as well as other diseases.

Complete Cure of Inoperable Stage IV Locally Advanced Hypopharyngeal Squamous Cell Carcinoma by an Innovative Combination Cancer Immunotherapy Consisting of Radiation, Immune Checkpoint Inhibitors, and Dendritic Cell Vaccine

We report the case of a 68-year-old man with locally advanced (LA) head and neck cancer (HNC) (LA-HNC). The patient was diagnosed with inoperable stage IVA hypopharyngeal squamous cell carcinoma with 2 cm primary and three lymph node metastatic cancers. The patient was treated with an innovative combination cancer immunotherapy (iCCI) consisting of radiotherapy, immune checkpoint inhibitors, and helper/killer-hybrid epitope long peptides (H/K-HELP)-pulsed dendritic cell vaccine. These three treatments constituting iCCI are known to show an immunomodulating effect on tumor-draining lymph nodes (TDLNs) and improve antitumor immunity in tumor microenvironments (TMEs) to reduce tumor growth. Surprisingly, the patient treated with iCCI showed a complete cure for all the cancers including primary and lymph node-metastatic cancers without standard chemotherapy. The patient is still cancer-free for almost two years. Although the destruction mechanism of cancer is not determined, we speculate this iCCI might improve the patient's antitumor immune capability around tumor sites including TDLNs and TME. Our developed iCCI will become a promising strategy to overcome inoperable cancers in the future.

Evaluating the immunologically "cold" tumor microenvironment after treatment with immune checkpoint inhibitors utilizing PET imaging of CD4 + and CD8 + T cells in breast cancer mouse models

BACKGROUND

Immune-positron emission tomography (PET) imaging with tracers that target CD8 and granzyme B has shown promise in predicting the therapeutic response following immune checkpoint blockade (ICB) in immunologically "hot" tumors. However, immune dynamics in the low T-cell infiltrating "cold" tumor immune microenvironment during ICB remain poorly understood. This study uses molecular imaging to evaluate changes in CD4 + T cells and CD8 + T cells during ICB in breast cancer models and examines biomarkers of response.

METHODS

[89Zr]Zr-DFO-CD4 and [89Zr]Zr-DFO-CD8 radiotracers were used to quantify changes in intratumoral and splenic CD4 T cells and CD8 T cells in response to ICB treatment in 4T1 and MMTV-HER2 mouse models, which represent immunologically "cold" tumors. A correlation between PET quantification metrics and long-term anti-tumor response was observed. Further biological validation was obtained by autoradiography and immunofluorescence.

RESULTS

Following ICB treatment, an increase in the CD8-specific PET signal was observed within 6 days, and an increase in the CD4-specific PET signal was observed within 2 days in tumors that eventually responded to immunotherapy, while no significant differences in CD4 or CD8 were found at the baseline of treatment that differentiated responders from nonresponders. Furthermore, mice whose tumors responded to ICB had a lower CD8 PET signal in the spleen and a higher CD4 PET signal in the spleen compared to non-responders. Intratumoral spatial heterogeneity of the CD8 and CD4-specific PET signals was lower in responders compared to non-responders. Finally, PET imaging, autoradiography, and immunofluorescence signals were correlated when comparing in vivo imaging to ex vivo validations.

CONCLUSIONS

CD4- and CD8-specific immuno-PET imaging can be used to characterize the in vivo distribution of CD4 + and CD8 + T cells in response to immune checkpoint blockade. Imaging metrics that describe the overall levels and distribution of CD8 + T cells and CD4 + T cells can provide insight into immunological alterations, predict biomarkers of response to immunotherapy, and guide clinical decision-making in those tumors where the kinetics of the response differ.

Microglia in Glioblastomas: Molecular Insight and Immunotherapeutic Potential

Glioblastoma (GBM) is one of the most aggressive and devastating primary brain tumors, with a median survival of 15 months following diagnosis. Despite the intense treatment regimen which routinely includes maximal safe neurosurgical resection followed by adjuvant radio- and chemotherapy, the disease remains uniformly fatal. The poor prognosis associated with GBM is multifactorial owing to factors such as increased proliferation, angiogenesis, and metabolic switching to glycolytic pathways. Critically, GBM-mediated local and systemic immunosuppression result in inadequate immune surveillance and ultimately, tumor-immune escape. Microglia-the resident macrophages of the central nervous system (CNS)-play crucial roles in mediating the local immune response in the brain. Depending on the specific pathological cues, microglia are activated into either a pro-inflammatory, neurotoxic phenotype, known as M1, or an anti-inflammatory, regenerative phenotype, known as M2. In either case, microglia secrete corresponding pro- or anti-inflammatory cytokines and chemokines that either promote or hinder tumor growth. Herein, we review the interplay between GBM cells and resident microglia with a focus on contemporary studies highlighting the effect of GBM on the subtypes of microglia expressed, the associated cytokines/chemokines secreted, and ultimately, their impact on tumor pathogenesis. Finally, we explore how understanding the intricacies of the tumor-immune landscape can inform novel immunotherapeutic strategies against this devastating disease.

Identification of a methyltransferase-related long noncoding RNA signature as a novel prognosis biomarker for lung adenocarcinoma

BACKGROUND

Lung adenocarcinoma (LUAD) accounts for a high proportion of tumor deaths globally, while methyltransferase-related lncRNAs in LUAD were poorly studied.

METHODS

In our study, we focused on two distinct cohorts, TCGA-LUAD and GSE3021, to establish a signature of methyltransferase-related long non-coding RNAs (MeRlncRNAs) in LUAD. We employed univariate Cox and LASSO regression analyses as our main analytical tools. The GSE30219 cohort served as the validation cohort for our findings. Furthermore, to explore the differential pathway enrichments between groups stratified by risk, we utilized Gene Set Enrichment Analysis (GSEA). Additionally, single-sample GSEA (ssGSEA) was conducted to assess the immune infiltration landscape within each sample. Reverse transcription quantitative PCR (RT-qPCR) was also performed to verify the expression of prognostic lncRNAs in both clinically normal and LUAD samples.

RESULTS

In LUAD, we identified a set of 32 MeRlncRNAs. We further narrowed our focus to six prognostic lncRNAs to develop gene signatures. The TCGA-LUAD cohort and GSE30219 were utilized to validate the risk score model derived from these signatures. Our analysis showed that the risk score served as an independent prognostic factor, linked to immune-related pathways. Additionally, the analysis of immune infiltration revealed that the immune landscape in high-risk groups was suppressed, which could contribute to poorer prognoses. We also constructed a regulatory network comprising 6 prognostic lncRNAs, 19 miRNAs, and 21 mRNAs. Confirmatory RT-qPCR results aligned with public database findings, verifying the expression of these prognostic lncRNAs in the samples.

CONCLUSION

The prognostic gene signature of LUAD associated with MeRlncRNAs that we provided, may offer us a comprehensive picture of the prognosis prediction for LUAD patients.

A Plausible Framework Reveals Potential Similarities in the Regulation of Immunity against Some Cancers and Some Infectious Agents: Implications for Prevention and Treatment

Different frameworks, which are currently employed to understand how immune responses are regulated, can account for different observations reported in the classical literature. I have argued that the predominant frameworks, employed over the last two/three decades to analyze the circumstances that determine whether an immune response is generated or this potential is ablated, and that determine the class of immunity an antigen induces, are inconsistent with diverse classical observations. These observations are "paradoxical" within the context of these frameworks and, consequently, tend to be ignored by most contemporary researchers. One such observation is that low and high doses of diverse types of antigen result, respectively, in cell-mediated and IgG antibody responses. I suggest these paradoxes render these frameworks implausible. An alternative framework, The Threshold Hypothesis, accounts for the paradoxical observations. Some frameworks are judged more plausible when found to be valuable in understanding findings in fields beyond their original compass. I explore here how the Threshold Hypothesis, initially based on studies with chemically well-defined and "simple antigens", most often a purified protein, can nevertheless shed light on diverse classical and more recent observations in the fields of immunity against cancer and against infectious agents, thus revealing common, immune mechanisms. Most cancers and some pathogens are best contained by cell-mediated immunity. The success of the Threshold Hypothesis has encouraged me to employ it as a basis for proposing strategies to prevent and to treat cancer and those infectious diseases caused by pathogens best contained by a cell-mediated attack.

Efficacy and safety of microwave ablation and its synergistic potential in the treatment of early-stage non-small cell lung cancer

Lung cancer remains the primary cause of cancer-related mortality globally. In the case of early-stage non-small cell lung cancer (NSCLC), surgical resection, such as lobectomy and sub-lobectomy, continues to be the established standard treatment. However, for patients with insufficient cardiopulmonary function and multiple comorbidities who are unable to undergo surgical resection, nonoperative local therapies, including radiotherapy and thermal ablation, are preferred. In recent years, microwave ablation (MWA) has gained popularity for treating early-stage NSCLC due to its high heating efficiency, good tissue conductance, and heat conduction capabilities. This review provides a comprehensive summary of the current efficacy and safety data regarding MWA for early-stage NSCLC and discusses the potential benefits of combining MWA with other therapies.

Y-Box Binding Protein 1: Unraveling the Multifaceted Role in Cancer Development and Therapeutic Potential

Y-box binding protein 1 (YBX1), a member of the Cold Shock Domain protein family, is overexpressed in various human cancers and is recognized as an oncogenic gene associated with poor prognosis. YBX1's functional diversity arises from its capacity to interact with a broad range of DNA and RNA molecules, implicating its involvement in diverse cellular processes. Independent investigations have unveiled specific facets of YBX1's contribution to cancer development. This comprehensive review elucidates YBX1's multifaceted role in cancer across cancer hallmarks, both in cancer cell itself and the tumor microenvironment. Based on this, we proposed YBX1 as a potential target for cancer treatment. Notably, ongoing clinical trials addressing YBX1 as a target in breast cancer and lung cancer have showcased its promise for cancer therapy. The ramp up in in vitro research on targeting YBX1 compounds also underscores its growing appeal. Moreover, the emerging role of YBX1 as a neural input is also proposed where the high level of YBX1 was strongly associated with nerve cancer and neurodegenerative diseases. This review also summarized the up-to-date advanced research on the involvement of YBX1 in pancreatic cancer.

Generation and quality control of mature monocyte-derived dendritic cells for immunotherapy

Dendritic cell vaccination is a form of active immunotherapy that aims to exploit the crucial role of DC in the initiation of T-cell responses. Numerous vaccination trials have been conducted targeting various tumor entities, including glioblastoma, the most frequent and aggressive malignant brain tumor in adults. They have demonstrated feasibility and safety and suggest improved survival, associated with induction of anti-tumoral immunity. Here, we describe in detail a large-scale 2-step protocol for successive GMP-compliant generation of immature and mature dendritic cells, yielding a highly homogenous population of CD83+ mature DC expressing CD40, CD80, CD86 and HLA-DR at high density, lacking activity of the immunosuppressive enzyme indoleamine-2,3-dioxygenase, migrating towards the chemokine CCL19 and showing highly potent T-cell stimulatory activity. Loaded with autologous tumor lysate, these cells are currently being evaluated in a phase II controlled randomized clinical trial (GlioVax) in glioblastoma patients.

Harnessing tumor immunity with cytotoxics: T cells monitoring in mice bearing lung tumors treated with anti-VEGF and pemetrexed-cisplatin doublet

BACKGROUND

Successful immunotherapy is restricted to some cancers only, and combinatorial strategies with other drugs could help to improve their efficacy. Here, we monitor T cells in NSCLC model after treatment with cytotoxics (CT) and anti-VEGF drugs, to understand when immune checkpoint inhibitors should be best associated next.

METHODS

In vivo study was performed on BALB/c mice grafted with KLN205 cells. Eight treatments were tested including control, cisplatin and pemetrexed as low (LD CT) and full (MTD CT) dose as single agents, flat dose anti-VEGF and the association anti-VEGF + CT. Full immunomonitoring was performed by flow cytometry on tumor, spleen and blood over 3 weeks.

RESULTS

Immunomodulatory effect was dependent upon both treatments and time. In tumors, combination groups shown numerical lower Treg cells on Day 21. In spleen, anti-VEGF and LD CT group shown higher CD8/Treg ratio on Day 7; on Day 14, higher T CD4 were observed in both combination groups. Finally, in blood, Tregs were lower and CD8/Treg ratio higher, on Day 14 in both combination groups. On Day 21, CD4 and CD8 T cells were higher in the anti-VEGF + MTD CT group.

CONCLUSIONS

Anti-VEGF associated to CT triggers notable increase in CD8/Tregs ratio. Regarding the scheduling, a two-week delay after using anti-VEGF and CT could be the best sequence to optimize antitumor efficacy.

Eosinophils in the tumor microenvironment: implications for cancer immunotherapy

Despite being an integral part of the immune response in the tumor microenvironment (TME), few studies have mechanistically elucidated eosinophil functions in cancer outcomes. Eosinophils are a minor population of granulocytes that are mostly explored in asthma and allergic disorders. Their influence on primary and metastatic tumors, however, has recently come to light. Eosinophils' diverse armamentarium of mediators and receptors allows them to participate in innate and adaptive immunity, such as type 1 and type 2 immunity, and shape TME and tumor outcomes. Based on TME cells and cytokines, activated eosinophils drive other immune cells to ultimately promote or suppress tumor growth. Discovering exactly what conditions determine the pro-tumorigenic or anti-tumorigenic role of eosinophils allows us to take advantage of these signals and devise novel strategies to target cancer cells. Here, we first revisit eosinophil biology and differentiation as recognizing eosinophil mediators is crucial to their function in homeostatic and pathological conditions as well as tumor outcome. The bulk of our paper discusses eosinophil interactions with tumor cells, immune cells-including T cells, plasma cells, natural killer (NK) cells-and gut microbiota. Eosinophil mediators, such as IL-5, IL-33, granulocyte-macrophage colony-stimulating factor (GM-CSF), thymic stromal lymphopoietin (TSLP), and CCL11 also determine eosinophil behavior toward tumor cells. We then examine the implications of these findings for cancer immunotherapy approaches, including immune checkpoint blockade (ICB) therapy using immune checkpoint inhibitors (ICIs) and chimeric antigen receptor (CAR) T cell therapy. Eosinophils synergize with CAR T cells and ICB therapy to augment immunotherapies.

Exploring the regulatory role of lncRNA in cancer immunity

Imbalanced immune homeostasis in cancer microenvironment is a hallmark of cancer. Increasing evidence demonstrated that long non-coding RNAs (lncRNAs) have emerged as key regulatory molecules in directly blocking the cancer immunity cycle, apart from activating negative regulatory pathways for restraining tumor immunity. lncRNAs reshape the tumor microenvironment via the recruitment and activation of innate and adaptive lymphoid cells. In this review, we summarized the versatile mechanisms of lncRNAs implicated in cancer immunity cycle, including the inhibition of antitumor T cell activation, blockade of effector T cell recruitment, disruption of T cell homing, recruitment of immunosuppressive cells, and inducing an imbalance between antitumor effector cells (cytotoxic T lymphocytes, M1 macrophages, and T helper type 1 cells) versus immunosuppressive cells (M2 macrophages, T helper type 2 cells, myeloid derived suppressor cells, and regulatory T cells) that infiltrate in the tumor. As such, we would highlight the potential of lncRNAs as novel targets for immunotherapy.

Thymus-derived hormonal and cellular control of cancer

The thymus gland is a central lymphoid organ in which developing T cell precursors, known as thymocytes, undergo differentiation into distinct type of mature T cells, ultimately migrating to the periphery where they exert specialized effector functions and orchestrate the immune responses against tumor cells, pathogens and self-antigens. The mechanisms supporting intrathymic T cell differentiation are pleiotropically regulated by thymic peptide hormones and cytokines produced by stromal cells in the thymic microenvironment and developing thymocytes. Interestingly, in the same way as T cells, thymic hormones (herein exemplified by thymosin, thymulin and thymopoietin), can circulate to impact immune cells and other cellular components in the periphery. Evidence on how thymic function influences tumor cell biology and response of patients with cancer to therapies remains unsatisfactory, although there has been some improvement in the knowledge provided by recent studies. Herein, we summarize research progression in the field of thymus-mediated immunoendocrine control of cancer, providing insights into how manipulation of the thymic microenvironment can influence treatment outcomes, including clinical responses and adverse effects of therapies. We review data obtained from clinical and preclinical cancer research to evidence the complexity of immunoendocrine interactions underpinning anti-tumor immunity.

Anti-tumor antibody isotype response can be modified with locally administered immunoadjuvants

In situ vaccination with immunostimulatory compounds is a demonstrated means to treat tumors preclinically. While these therapeutic effects have been attributed to the actions of T cells or innate immune activation, characterisation of the humoral immune response is seldom performed. This study aims to identify whether the injection of immunoadjuvants, Addavax (Adda) and cytosine-phosphorothioate-guanine oligodeoxynucleotide (CpG), intratumorally can influence the antibody response. Specifically, whether intratumoral injection of immunoadjuvants can alter the tumor-specific antibody target, titre and isotype. Following this, the study aimed to investigate whether serum obtained from in situ vaccinated mice could neutralise circulating tumor cells. Serum was obtained from mice bearing B16F10-OVA-Luc-GFP tumors treated with immunoadjuvants. Antibody targets' titre and isotype were assessed by indirect ELISA. The ability of serum to neutralise circulating cancer cells was evaluated in a B16F10 pseudo-metastatic model. It was observed that tumor-bearing mice mount a specific anti-tumor antibody response. Antibody titre and target were unaffected by in situ vaccination with immunoadjuvants; however, a higher amount of IgG2c was produced in mice receiving Adda plus CpG. Serum from in situ vaccinated mice was unable to neutralise circulating B16F10 cells. Thus, this study has demonstrated that anti-tumor antibody isotype may be modified using in situ vaccination; however, this alone is not sufficient to neutralise circulating cancer cells.

Melanoma Clinical Decision Support System: An Artificial Intelligence-Based Tool to Diagnose and Predict Disease Outcome in Early-Stage Melanoma Patients

This study set out to assess the performance of an artificial intelligence (AI) algorithm based on clinical data and dermatoscopic imaging for the early diagnosis of melanoma, and its capacity to define the metastatic progression of melanoma through serological and histopathological biomarkers, enabling dermatologists to make more informed decisions about patient management. Integrated analysis of demographic data, images of the skin lesions, and serum and histopathological markers were analyzed in a group of 196 patients with melanoma. The interleukins (ILs) IL-4, IL-6, IL-10, and IL-17A as well as IFNγ (interferon), GM-CSF (granulocyte and macrophage colony-stimulating factor), TGFβ (transforming growth factor), and the protein DCD (dermcidin) were quantified in the serum of melanoma patients at the time of diagnosis, and the expression of the RKIP, PIRIN, BCL2, BCL3, MITF, and ANXA5 proteins was detected by immunohistochemistry (IHC) in melanoma biopsies. An AI algorithm was used to improve the early diagnosis of melanoma and to predict the risk of metastasis and of disease-free survival. Two models were obtained to predict metastasis (including "all patients" or only patients "at early stages of melanoma"), and a series of attributes were seen to predict the progression of metastasis: Breslow thickness, infiltrating BCL-2 expressing lymphocytes, and IL-4 and IL-6 serum levels. Importantly, a decrease in serum GM-CSF seems to be a marker of poor prognosis in patients with early-stage melanomas.

Intratumor childhood vaccine-specific CD4+ T-cell recall coordinates antitumor CD8+ T cells and eosinophils

BACKGROUND

Antitumor mechanisms of CD4⁺ T cells remain crudely defined, and means to effectively harness CD4⁺ T-cell help for cancer immunotherapy are lacking. Pre-existing memory CD4⁺ T cells hold potential to be leveraged for this purpose. Moreover, the role of pre-existing immunity in virotherapy, particularly recombinant poliovirus immunotherapy where childhood polio vaccine specific immunity is ubiquitous, remains unclear. Here we tested the hypothesis that childhood vaccine-specific memory T cells mediate antitumor immunotherapy and contribute to the antitumor efficacy of polio virotherapy.

METHODS

The impact of polio immunization on polio virotherapy, and the antitumor effects of polio and tetanus recall were tested in syngeneic murine melanoma and breast cancer models. CD8⁺ T-cell and B-cell knockout, CD4⁺ T-cell depletion, CD4⁺ T-cell adoptive transfer, CD40L blockade, assessments of antitumor T-cell immunity, and eosinophil depletion defined antitumor mechanisms of recall antigens. Pan-cancer transcriptome data sets and polio virotherapy clinical trial correlates were used to assess the relevance of these findings in humans.

RESULTS

Prior vaccination against poliovirus substantially bolstered the antitumor efficacy of polio virotherapy in mice, and intratumor recall of poliovirus or tetanus immunity delayed tumor growth. Intratumor recall antigens augmented antitumor T-cell function, caused marked tumor infiltration of type 2 innate lymphoid cells and eosinophils, and decreased proportions of regulatory T cells (Tregs). Antitumor effects of recall antigens were mediated by CD4⁺ T cells, limited by B cells, independent of CD40L, and dependent on eosinophils and CD8⁺ T cells. An inverse relationship between eosinophil and Treg signatures was observed across The Cancer Genome Atlas (TCGA) cancer types, and eosinophil depletion prevented Treg reductions after polio recall. Pretreatment polio neutralizing antibody titers were higher in patients living longer, and eosinophil levels increased in the majority of patients, after polio virotherapy.

CONCLUSION

Pre-existing anti-polio immunity contributes to the antitumor efficacy of polio virotherapy. This work defines cancer immunotherapy potential of childhood vaccines, reveals their utility to engage CD4⁺ T-cell help for antitumor CD8⁺ T cells, and implicates eosinophils as antitumor effectors of CD4⁺ T cells.

Role and Potential of Different T Helper Cell Subsets in Adoptive Cell Therapy

Historically, CD8⁺ T cells have been considered the most relevant effector cells involved in the immune response against tumors and have therefore been the focus of most cancer immunotherapy approaches. However, CD4⁺ T cells and their secreted factors also play a crucial role in the tumor microenvironment and can orchestrate both pro- and antitumoral immune responses. Depending on the cytokine milieu to which they are exposed, CD4⁺ T cells can differentiate into several phenotypically different subsets with very divergent effects on tumor progression. In this review, we provide an overview of the current knowledge about the role of the different T helper subsets in the immune system, with special emphasis on their implication in antitumoral immune responses. Furthermore, we also summarize therapeutic applications of each subset and its associated cytokines in the adoptive cell therapy of cancer.

Cellular Senescence as a Brake or Accelerator for Oncogenic Transformation and Role in Lymphatic Metastasis

Cellular senescence-the irreversible cell cycle arrest driven by a variety of mechanisms and, more specifically, the senescence-associated secretory phenotype (SASP)-is an important area of research in the context of different age-related diseases, such as cardiovascular disease and cancer. SASP factors play both beneficial and detrimental roles in age-related disease progression depending on the source of the SASPs, the target cells, and the microenvironment. The impact of senescence and the SASP on different cell types, the immune system, and the vascular system has been widely discussed. However, the impact of replicative or stress-induced senescence on lymphatic biology and pathological lymphangiogenesis remains underexplored. The lymphatic system plays a crucial role in the maintenance of body fluid homeostasis and immune surveillance. The perturbation of lymphatic function can hamper normal physiological function. Natural aging or stress-induced premature aging influences the lymphatic vessel structure and function, which significantly affect the role of lymphatics in tumor dissemination and metastasis. In this review, we focus on the role of senescence on lymphatic pathobiology, its impact on cancer, and potential therapeutic interventions to manipulate the aged or senescent lymphatic system for disease management.

Targeting Ibrutinib to Tumor-Infiltrating T Cells with a Sialic Acid Conjugate-Modified Phospholipid Complex for Improved Tumor Immunotherapy

Immune checkpoint blockade (ICB) treatment for the clinical therapy of numerous malignancies has attracted widespread attention in recent years. Despite being a promising treatment option, developing complementary strategies to enhance the proportion of patients benefiting from ICB therapy remains a formidable challenge because of the complexity of the tumor microenvironment. Ibrutinib (IBR), a covalent inhibitor of Bruton's tyrosine kinase (BTK), has been approved as a clinical therapy for numerous B-cell malignancies. IBR also irreversibly inhibits interleukin-2 inducible T cell kinase (ITK), an essential enzyme in Th2-polarized T cells that participates in tumor immunosuppression. Ablation of ITK by IBR can elicit Th1-dominant antitumor immune responses and potentially enhance the efficacy of ICB therapy in solid tumors. However, its poor solubility and rapid clearance in vivo restrict T cell targetability and tumor accumulation by IBR. A sialic acid derivative-modified nanocomplex (SA-GA-OCT@PC) has been reported to improve the efficacy of IBR-mediated combination immunotherapy in solid tumors. In vitro and in vivo experiments showed that SA-GA-OCT@PC effectively accumulated in tumor-infiltrating T cells mediated by Siglec-E and induced Th1-dominant antitumor immune responses. SA-GA-OCT@PC-mediated combination therapy with PD-L1 blockade agents dramatically suppressed tumor growth and inhibited tumor relapse in B16F10 melanoma mouse models. Overall, the combination of the SA-modified nanocomplex platform and PD-L1 blockade offers a treatment opportunity for IBR in solid tumors, providing novel insights for tumor immunotherapy.

Distinct T helper cell-mediated antitumor immunity: T helper 2 cells in focus

The adaptive arm of the immune system is crucial for appropriate antitumor immune responses. It is generally accepted that clusters of differentiation 4+ (CD4+) T cells, which mediate T helper (Th) 1 immunity (type 1 immunity), are the primary Th cell subtype associated with tumor elimination. In this review, we discuss evidence showing that antitumor immunity and better prognosis can be associated with distinct Th cell subtypes in experimental mouse models and humans, with a focus on Th2 cells. The aim of this review is to provide an overview and understanding of the mechanisms associated with different tumor outcomes in the face of immune responses by focusing on the (1) site of tumor development, (2) tumor properties (i. e., tumor metabolism and cytokine receptor expression), and (3) type of immune response that the tumor initially escaped. Therefore, we discuss how low-tolerance organs, such as lungs and brains, might benefit from a less tissue-destructive immune response mediated by Th2 cells. In addition, Th2 cells antitumor effects can be independent of CD8+ T cells, which would circumvent some of the immune escape mechanisms that tumor cells possess, like low expression of major histocompatibility-I (MHC-I). Finally, this review aims to stimulate further studies on the role of Th2 cells in antitumor immunity and briefly discusses emerging treatment options.

Th2 cells inhibit growth of colon and pancreas cancers by promoting anti-tumorigenic responses from macrophages and eosinophils

BACKGROUND

Immunotherapy of gastrointestinal cancers is challenging; however, several lines of evidence suggest that adoptive transfer of stimulated or modified immune cells support not only protective role of immune cells in tumor microenvironment, but actively participate in the elimination of cancer cells.

METHODS

In vivo studies employing cancer cell-derived allograft murine models of gastrointestinal cancers were performed. The effects of T helper (Th) 2 cells on gastrointestinal cancers growth and tumor microenvironment composition using adoptive transfer of Th2 cells, interleukin (IL)-5 treatment, and immunofluorescence, multiplex and real-time PCR were explored.

RESULTS

Here, we show that Th2 cells play an essential role in the inhibition of colon and pancreas cancers progression. In murine models of gastrointestinal tumors using adoptive transfer of Th2 cells, we identify that Th2 cells are responsible for generation of apoptotic factors and affect macrophage as well as eosinophil recruitment into tumors where they produce cytotoxic factors. Moreover, we found that Th2 cells lead to IL-5 hypersecretion, which links the anti-tumorigenic function of Th2 cells and eosinophils. Importantly, we noted that recombinant IL-5 administration is also related with inhibition of gastrointestinal tumor growth. Finally, using an in vitro approach, we documented that both Th2 cells and eosinophils are directly responsible for gastrointestinal cancer cell killing.

CONCLUSIONS

These data demonstrate the significance of Th2 cells, eosinophils and IL-5 in the inhibition of gastrointestinal tumor growth, and pointed toward tumor microenvironment reprogramming as a Th2 cell-mediated anti-tumorigenic mechanism of action.

Toward Establishing an Ideal Adjuvant for Non-Inflammatory Immune Enhancement

The vertebrate immune system functions to eliminate invading foreign nucleic acids and foreign proteins from infectious diseases and malignant tumors. Because pathogens and cancer cells have unique amino acid sequences and motifs (e.g., microbe-associated molecular patterns, MAMPs) that are recognized as "non-self" to the host, immune enhancement is one strategy to eliminate invading cells. MAMPs contain nucleic acids specific or characteristic of the microbe and are potential candidates for immunostimulants or adjuvants. Adjuvants are included in many vaccines and are a way to boost immunity by deliberately administering them along with antigens. Although adjuvants are an important component of vaccines, it is difficult to evaluate their efficacy ex vivo and in vivo on their own (without antigens). In addition, inflammation induced by currently candidate adjuvants may cause adverse events, which is a hurdle to their approval as drugs. In addition, the lack of guidelines for evaluating the safety and efficacy of adjuvants in drug discovery research also makes regulatory approval difficult. Viral double-stranded (ds) RNA mimics have been reported as potent adjuvants, but the safety barrier remains unresolved. Here we present ARNAX, a noninflammatory nucleic acid adjuvant that selectively targets Toll-like receptor 3 (TLR3) in antigen-presenting dendritic cells (APCs) to safely induce antigen cross-presentation and subsequently induce an acquired immune response independent of inflammation. This review discusses the challenges faced in the clinical development of novel adjuvants.

Thymic stromal lymphopoietin-stimulated CD4+ T cells induce senescence in advanced breast cancer

Thymic Stromal Lymphopoietin (TSLP) plays a prominent role in inducing type 2 immune response, commonly associated with atopic diseases. TSLP-activated CD4+ T helper 2 cells block early carcinogenesis by inducing terminal differentiation in spontaneous breast and lung cancer models. However, the impact of TSLP induction on advanced cancer with altered cellular phenotypes is unclear. Using an established MMTV-PyMttg breast cancer cell line, we demonstrate that TSLP-stimulated CD4+ T cells possess an antitumor effect in advanced breast cancer. In contrast to early breast cancer suppression, the antitumor immunity mediated by TSLP-stimulated CD4+ T cells in advanced breast cancer is mediated by the induction of a senescent-like phenotype in cancer cells. Inflammatory CD4+ T cells drive breast cancer cells into senescence by releasing interferon-gamma and tumor necrosis factor-alpha, which directly bind to their receptors on cancer cells. Our findings reveal a novel mechanism of TSLP-activated CD4+ T cell immunity against advanced breast cancer, mediated by cellular senescence as a distinct effector mechanism for cancer immunotherapy.

rhCNB Improves Cyclophosphamide-Induced Immunodeficiency in BALB/c Mice

Background

This study aims to explore the immunomodulatory effect of rhCNB on mice with cyclophosphamide (CTX)-induced immunodeficiency through TLR₄/MAPK pathway.

Methods

BALB/c mice were randomly divided into three groups: a negative control group, an immunosuppression model group, and a rhCNB treatment group. Tail vein injection of cyclophosphamide (40 mg/kg) was used to establish a mouse immunosuppression model. Intraperitoneal injection of rhCNB (20 mg/kg) was administered to the treatment group, whereas equal quantities of normal saline were given to the control group and model group. Perform peripheral blood routine of CD4, CD8, and CD19 lymphocyte subsets and peripheral blood Th1/Th2 cell subsets 24 hours after the last administration. RT-PCR was used to detect mRNA levels of TLR₄, P38, JNK, T-bet, and GATA₃, the spleen immune organ index was measured, and the histopathological status of the spleen and thymus was observed.

Results

The results showed that compared with the control group, WBC, PLT, LYM, NEU, immune organ index, CD4⁺/CD8⁺ and CD19⁺ subgroup ratio, and peripheral blood Th1/Th2 cell subgroups decreased in the model group. The mRNA levels of TLR₄, P38, JNK, T-bet, and GATA₃ decreased compared with the model group, while they increased in the treatment group.

Conclusions

rhCNB has an immunomodulatory effect by regulating the expression of Th1/Th2 cytokine balance through the TLR₄/MAPK signaling pathway and promoting the differentiation and proliferation of lymphocytes, thereby improving the immune function.

A brief glimpse of a tangled web in a small world: Tumor microenvironment

A tumor is a result of stepwise accumulation of genetic and epigenetic alterations. This notion has deepened the understanding of cancer biology and has introduced the era of targeted therapies. On the other hand, there have been a series of attempts of using the immune system to treat tumors, dating back to ancient history, to sporadic reports of inflamed tumors undergoing spontaneous regression. This was succeeded by modern immunotherapies and immune checkpoint inhibitors. The recent breakthrough has broadened the sight to other players within tumor tissue. Tumor microenvironment is a niche or a system orchestrating reciprocal and dynamic interaction of various types of cells including tumor cells and non-cellular components. The output of this complex communication dictates the functions of the constituent elements present within it. More complicated factors are biochemical and biophysical settings unique to TME. This mini review provides a brief guide on a range of factors to consider in the TME research.

The expression pattern of Immune checkpoints after chemo/radiotherapy in the tumor microenvironment

As a disease with the highest disease-associated burden worldwide, cancer has been the main subject of a considerable proportion of medical research in recent years, intending to find more effective therapeutic approaches with fewer side effects. Combining conventional methods with newer biologically based treatments such as immunotherapy can be a promising approach to treating different tumors. The concept of "cancer immunoediting" that occurs in the field of the tumor microenvironment (TME) is the aspect of cancer therapy that has not been at the center of attention. One group of the role players of the so-called immunoediting process are the immune checkpoint molecules that exert either co-stimulatory or co-inhibitory effects in the anti-tumor immunity of the host. It involves alterations in a wide variety of immunologic pathways. Recent studies have proven that conventional cancer therapies, such as chemotherapy, radiotherapy, or a combination of them, i.e., chemoradiotherapy, alter the "immune compartment" of the TME. The mentioned changes encompass a wide range of variations, including the changes in the density and immunologic type of the tumor-infiltrating lymphocytes (TILs) and the alterations in the expression patterns of the different immune checkpoints. These rearrangements can have either anti-tumor immunity empowering or immune attenuating sequels. Thus, recognizing the consequences of various chemo(radio)therapeutic regimens in the TME seems to be of great significance in the evolution of therapeutic approaches. Therefore, the present review intends to summarize how chemo(radio)therapy affects the TME and specifically some of the most important, well-known immune checkpoints' expressions according to the recent studies in this field.

Th1-Dominant CD4+ T Cells Orchestrate Endogenous Systematic Antitumor Immune Memory After Cryo-Thermal Therapy

Recent studies suggest that highly activated, polyfunctional CD4⁺ T cells are incredibly effective in strengthening and sustaining overall host antitumor immunity, promoting tumor-specific CD4⁺ T-cell responses and effectively enhancing antitumor immunity by immunotherapy. Previously, we developed a novel cryo-thermal therapy for local tumor ablation and achieved long-term survival rates in several tumor models. It was discovered that cryo-thermal therapy remodeled the tumor microenvironment and induced an antigen-specific CD4⁺ T-cell response, which mediated stronger antitumor immunity in vivo. In this study, the phenotype of bulk T cells in spleen was analyzed by flow cytometry after cryo-thermal therapy and both CD4⁺ Th1 and CD8⁺ CTL were activated. In addition, by using T-cell depletion, isolation, and adoptive T-cell therapy, it was found that cryo-thermal therapy induced Th1-dominant CD4⁺ T cells that directly inhibited the growth of tumor cells, promoted the maturation of MDSCs via CD4⁺ T-cell-derived IFN-γ and enhanced the cytotoxic effector function of NK cells and CD8⁺ T cells, and promoted the maturation of APCs via cell-cell contact and CD4⁺ T-cell-derived IFN-γ. Considering the multiple roles of cryo-thermal-induced Th1-dominant CD4⁺ T cells in augmenting antitumor immune memory, we suggest that local cryo-thermal therapy is an attractive thermo-immunotherapy strategy to harness host antitumor immunity and has great potential for clinical application.

Babesia microti Infection Inhibits Melanoma Growth by Activating Macrophages in Mice

Babesia microti is an obligate intraerythrocytic protozoan transmitted by an Ixodes tick. Infections caused by protozoa, including Plasmodium yoelii and Toxoplasma gondii, are shown to inhibit tumor development by activating immune responses. Th1 immune response and macrophages not only are essential key factors in Babesia infection control but also play an important role in regulating tumor development. In this study, we investigated the effects of B. microti infection on melanoma in tumor-bearing mice. The results showed that B. microti infection could inhibit the growth of melanoma, significantly enlarge the spleen size (p ≤ 0.0001), and increase the survival period (over 7 days) of tumor-bearing mice. Mouse spleen immune cell analysis revealed that B. microti-infected tumor-bearing mice could increase the number of macrophages and CD4+ T cells, as well as the proportion of CD4+ T cells and M1 macrophages in the tumor. Immunohistochemical assays showed that B. microti infection could inhibit tumor angiogenesis (p ≤ 0.0032). Meanwhile, both B. microti-infected erythrocytes and culture supernatant were observed to significantly (p ≤ 0.0021) induce the mRNA expression of iNOS, IL-6, and TNF-α in macrophages. Moreover, B. microti culture supernatant could also repolarize IL-4-induced M2 macrophages to the M1 type. Overall, B. microti exerted antitumor effects by stimulating the immune system of tumor-bearing mice and inducing the polarization of immunosuppressive M2 macrophages to pro-inflammatory M1 macrophages.

Regulation of the antigen presentation machinery in cancer and its implication for immune surveillance

Evading immune destruction is one of the hallmarks of cancer. A key mechanism of immune evasion deployed by tumour cells is to reduce neoantigen presentation through down-regulation of the antigen presentation machinery. MHC-I and MHC-II proteins are key components of the antigen presentation machinery responsible for neoantigen presentation to CD8⁺ and CD4⁺ T lymphocytes, respectively. Their expression in tumour cells is modulated by a complex interplay of genomic, transcriptomic and post translational factors involving multiple intracellular antigen processing pathways. Ongoing research investigates mechanisms invoked by cancer cells to abrogate MHC-I expression and attenuate anti-tumour CD8⁺ cytotoxic T cell response. The discovery of MHC-II on tumour cells has been less characterized. However, this finding has triggered further interest in utilising tumour-specific MHC-II to harness sustained anti-tumour immunity through the activation of CD4⁺ T helper cells. Tumour-specific expression of MHC-I and MHC-II has been associated with improved patient survival in most clinical studies. Thus, their reactivation represents an attractive way to unleash anti-tumour immunity. This review provides a comprehensive overview of physiologically conserved or novel mechanisms utilised by tumour cells to reduce MHC-I or MHC-II expression. It outlines current approaches employed at the preclinical and clinical trial interface towards reversing these processes in order to improve response to immunotherapy and survival outcomes for patients with cancer.

Dual Effect of Immune Cells within Tumour Microenvironment: Pro- and Anti-Tumour Effects and Their Triggers

Our body is constantly exposed to pathogens or external threats, but with the immune response that our body can develop, we can fight off and defeat possible attacks or infections. Nevertheless, sometimes this threat comes from an internal factor. Situations such as the existence of a tumour also cause our immune system (IS) to be put on alert. Indeed, the link between immunology and cancer is evident these days, with IS being used as one of the important targets for treating cancer. Our IS is able to eliminate those abnormal or damaged cells found in our body, preventing the uncontrolled proliferation of tumour cells that can lead to cancer. However, in several cases, tumour cells can escape from the IS. It has been observed that immune cells, the extracellular matrix, blood vessels, fat cells and various molecules could support tumour growth and development. Thus, the developing tumour receives structural support, irrigation and energy, among other resources, making its survival and progression possible. All these components that accompany and help the tumour to survive and to grow are called the tumour microenvironment (TME). Given the importance of its presence in the tumour development process, this review will focus on one of the components of the TME: immune cells. Immune cells can support anti-tumour immune response protecting us against tumour cells; nevertheless, they can also behave as pro-tumoural cells, thus promoting tumour progression and survival. In this review, the anti-tumour and pro-tumour immunity of several immune cells will be discussed. In addition, the TME influence on this dual effect will be also analysed.

Expression of PD‑L1 and CD4+ tumor‑infiltrating lymphocytes predict survival in head and neck squamous cell carcinoma

The clinical efficacy of immune checkpoint blockade has been recently demonstrated in a variety of cancer types. The aim of the present study was to characterize the expression profile of tumor-infiltrating lymphocytes (TILs) and programmed death-ligand 1 (PD-L1) in head and neck squamous carcinoma (HNSCC). A total of 63 patients with HNSCC were enrolled in the present study. CD3⁺ and CD4⁺ TILs and the expression of PD-L1 were detected by immunohistochemistry. PD-L1 mRNA levels were evaluated by reverse transcription-quantitative PCR analysis. The association of TILs and PD-L1 with patient clinicopathological characteristics was also assessed. CD3⁺ and CD4⁺ TILs were detected in 100% of the samples. CD3⁺ was the predominant subset of TILs. PD-L1 was expressed in 53 of 61 (86%) patients when a score of ≥1 on tumor cells was considered positive and in 28 patients (45.2%) when a score of >5 on tumor cells was considered positive. PD-L1 mRNA levels were determined to be significantly correlated with PD-L1 protein expression. Survival analysis demonstrated that high CD4⁺ TILs were associated with improved overall survival (OS) and disease-free survival (DFS), and furthermore, the association of high PD-L1 expression with unfavorable OS and DFS was statistically significant. Multivariate analysis identified CD4⁺ TILs and PD-L1 as prognostic markers for HNSCC. The results of the present study suggested that increased CD4⁺ TILs in HNSCC may be associated with improved outcomes, while high expression of PD-L1 may indicate unfavorable OS and DFS; thus, these factors may serve as predictors of the response to immune checkpoint therapy.

Directing the Future Breakthroughs in Immunotherapy: The Importance of a Holistic Approach to the Tumour Microenvironment

Simple Summary

Immunotherapies have changed the way we treat cancer and, while some patients have benefitted greatly, there are still those that do not respond to therapy. Understanding why some patients respond to therapy and others do not is critical in developing new immunotherapeutic strategies. The increasing awareness of the importance of investigating the tumour in its entirety, including the surrounding tissue and role of various immune cells is helping to differentiate responders and non-responders. In addition, the resolution gained by the development of sophisticated bioinformatic technologies allows for a deeper understanding of the complex roles of individual cells in the tumour. This advancement will be critical for the development of novel therapies to treat cancer.

Abstract

Immunotherapy has revolutionised the treatment of cancers by exploiting the immune system to eliminate tumour cells. Despite the impressive response in a proportion of patients, clinical benefit has been limited thus far. A significant focus to date has been the identification of specific markers associated with response to immunotherapy. Unfortunately, the heterogeneity between patients and cancer types means identifying markers of response to therapy is inherently complex. There is a growing appreciation for the role of the tumour microenvironment (TME) in directing response to immunotherapy. The TME is highly heterogeneous and contains immune, stromal, vascular and tumour cells that all communicate and interact with one another to form solid tumours. This review analyses major cell populations present within the TME with a focus on their diverse and often contradictory roles in cancer and how this informs our understanding of immunotherapy. Furthermore, we discuss the role of integrated omics in providing a comprehensive view of the TME and demonstrate the potential of leveraging multi-omics to decipher the underlying mechanisms of anti-tumour immunity for the development of novel immunotherapeutic strategies.

Dendritic Cell Vaccination of Glioblastoma: Road to Success or Dead End

Glioblastomas (GBM) are the most frequent and aggressive malignant primary brain tumor and remains a therapeutic challenge: even after multimodal therapy, median survival of patients is only 15 months. Dendritic cell vaccination (DCV) is an active immunotherapy that aims at inducing an antitumoral immune response. Numerous DCV trials have been performed, vaccinating hundreds of GBM patients and confirming feasibility and safety. Many of these studies reported induction of an antitumoral immune response and indicated improved survival after DCV. However, two controlled randomized trials failed to detect a survival benefit. This raises the question of whether the promising concept of DCV may not hold true or whether we are not yet realizing the full potential of this therapeutic approach. Here, we discuss the results of recent vaccination trials, relevant parameters of the vaccines themselves and of their application, and possible synergies between DCV and other therapeutic approaches targeting the immunosuppressive microenvironment of GBM.

The Immune Infiltration in HNSCC and Its Clinical Value: A Comprehensive Study Based on the TCGA and GEO Databases

BACKGROUND

Being potential field of research for tumor immunological therapy, the head and neck squamous cell carcinoma (HNSCC) is one of most discussed types of tumor. Recently, some clinical trials have also used immunological therapy and demonstrated a subset of HNSCC patients who have shown a clear longer survival time.

OBJECTIVE

To conduct further studies and deeper research in the immunological oncology of HNSCC, a more detailed description and comprehending of the complicated landscape of immune infiltrative may be required.

METHODS

Firstly, we have described the fraction of different infiltrating immune cells in the HNSCC tumor and then compared it to the normal tissue, and secondly, we have explored the clinical implications of various infiltrated immune cell fractions meticulously. The gene expression profiles of HNSCC tissue were obtained from databases of TCGA and GEO and utilized the deconvolution algorithm (CIBERSORT) to presume the fractions of 22 several immune sensitive cells.

RESULTS

Our results indicated that the immune infiltrating cell fractions were considerably different between HNSCC tumor tissue and paired normal tissue, but at the same time, we found a potential internal correlation among the immune cells and also showed the association between immune infiltrating cells and their clinical characteristics. It is worth noting that the resting dendritic cells and M1 macrophages were linked with a favorable prognosis, while the CD4+ T cells with a poorer outcome.

CONCLUSION

Fractions of immune cell percentage were also associated with tumors' pathological grade, age, and TNM stage.

Possible Immunotherapeutic Strategies Based on Carcinogen-Dependent Subgroup Classification for Oral Cancer

The oral cavity serves as an open local organ of the human body, exposed to multiple external factors from the outside environment. Coincidentally, initiation and development of oral cancer are attributed to many external factors, such as smoking and drinking, to a great extent. This phenomenon was partly explained by the genetic abnormalities traditionally induced by carcinogens. However, more and more attention has been attracted to the influence of carcinogens on the local immune status. On the other hand, immune heterogeneity of cancer patients is a huge obstacle for enhancing the clinical efficacy of tumor immunotherapy. Thus, in this review, we try to summarize the current opinions about variant genetic changes and multiple immune alterations induced by different oral cancer carcinogens and discuss the prospects of targeted immunotherapeutic strategies based on specific immune abnormalities caused by different carcinogens, as a predictive way to improve clinical outcomes of immunotherapy-treated oral cancer patients.

RAN and YBX1 are required for cell proliferation and IL-4 expression and linked to poor prognosis in oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC) is one of the most common malignancies in the world, with a high mortality rate. RAN is a member of the Ras GTPase family and is overexpressed in a range of cancers, however, the relationship between RAN and OSCC is rarely reported. In this study, we found that RAN is overexpressed in OSCC tissues. RAN inhibition retarded OSCC cell proliferation and led to apoptosis and cell cycle arrest. Knockdown of RAN inhibited tumor growth in vivo. Strikingly, we found that RAN and oncogene Y-box binding protein-1 (YBX1) are positively associated with the immune infiltrates of CD4⁺ Th2 cells in multiple types of cancer, and can promote IL-4 expression. IL-4 treatment can partially rescue RAN knockdown-induced cell apoptosis in OSCC cells. Moreover, overexpression of RAN could rescue cell growth inhibition caused by knockdown of YBX1. Furthermore, patients with low expression of both RAN and YBX1 had better overall survival than others. Collectively, these findings indicate that RAN is a target of YBX1. RAN and YBX1 are required for cell proliferation and IL-4 expression. RAN and YBX1 are co-expressed and can serve as potential co-biomarkers for poor prognosis in OSCC.

Immunity beyond cancer cells: perspective from tumor tissue

Investigation of cancer as a cell-level disease has led to the development of cancer cell-directed therapies including cytotoxic T lymphocyte (CTL)-based immunotherapy; yet, many patients are refractory to these modalities of cancer treatment and acquired resistance frequently occurs. Of note, cancer environment controls the manifestation of cancerous cell phenotype. Helper T (Th) cells orchestrate immune defense responses targeting cancer cells as well as the tumor microenvironment. Recent studies have shown that in addition to interferon (IFN)-γ-producing Th1 cells, interleukin (IL)-4-producing Th2 cells function as potent anticancer effectors in part by promoting tumor stroma reconfiguration and tumor tissue repair. Such Th cell-mediated tissue-level immunity may be harnessed for novel modalities of cancer environment immunotherapy.

Identification of Somatic Mutation-Driven Immune Cells by Integrating Genomic and Transcriptome Data

Tumor somatic mutations in protein-coding regions may generate neoantigens which may trigger antitumor immune cell response. Increasing evidence supports that immune cell response may profoundly influence tumor progression. However, there are no calculated tools to systematically identify immune cells driven by specific somatic mutations. It is urgent to develop a calculated method to comprehensively detect tumor-infiltrating immune cells driven by the specific somatic mutations in cancer. We developed a novel software package (SMDIC) that enables the automated identification of somatic mutation-driven immune cell. SMDIC provides a novel pipeline to discover mutation-specific immune cells by integrating genomic and transcriptome data. The operation modes include inference of the relative abundance matrix of tumor-infiltrating immune cells, detection of differential abundance immune cells with respect to the gene mutation status, conversion of the abundance matrix of significantly dysregulated cells into two binary matrices (one for upregulated and one for downregulated cells), identification of somatic mutation-driven immune cells by comparing the gene mutation status with each immune cell in the binary matrices across all samples, and visualization of immune cell abundance of samples in different mutation status for each gene. SMDIC provides a user-friendly tool to identify somatic mutation-specific immune cell response. SMDIC may contribute to understand the mechanisms underlying anticancer immune response and find targets for cancer immunotherapy. The SMDIC was implemented as an R-based tool which was freely available from the CRAN website https://CRAN.R-project.org/package=SMDIC.

Perspectives on Hypoxia Signaling in Tumor Stroma

Hypoxia is a well-known characteristic of solid tumors that contributes to tumor progression and metastasis. Oxygen deprivation due to high demand of proliferating cancer cells and standard of care therapies induce hypoxia. Hypoxia signaling, mainly mediated by the hypoxia-inducible transcription factor (HIF) family, results in tumor cell migration, proliferation, metabolic changes, and resistance to therapy. Additionally, the hypoxic tumor microenvironment impacts multiple cellular and non-cellular compartments in the tumor stroma, including disordered tumor vasculature, homeostasis of ECM. Hypoxia also has a multifaceted and often contradictory influence on immune cell function, which contributes to an immunosuppressive environment. Here, we review the important function of HIF in tumor stromal components and summarize current clinical trials targeting hypoxia. We provide an overview of hypoxia signaling in tumor stroma that might help address some of the challenges associated with hypoxia-targeted therapies.

Development of a Virus-Like Particle-Based Anti-HER2 Breast Cancer Vaccine

To develop a human epidermal growth factor receptor-2 (HER2)-specific cancer vaccine, using a plant virus-like particle (VLP) platform. Copper-free click chemistry and infusion encapsulation protocols were developed to prepare VLPs displaying the HER2-derived CH401 peptide epitope, with and without Toll-like receptor 9 (TLR9) agonists loaded into the interior cavity of the VLPs; Physalis mottle virus (PhMV)-based VLPs were used. After prime-boost immunization of BALB/c mice through subcutaneous administration of the vaccine candidates, sera were collected and analyzed by enzyme-linked immunosorbent assay (ELISA) for the CH401-specific antibodies; Th1 vs. Th2 bias was determined by antibody subtyping and splenocyte assay. Efficacy was assessed by tumor challenge using DDHER2 tumor cells. We successful developed two VLP-based anti-HER2 vaccine candidates-PhMV-CH401 vs. CpG-PhMV-CH401; however, the addition of the CpG adjuvant did not confer additional immune priming. Both VLP-based vaccine candidates elicited a strong immune response, including high titers of HER2-specific immunoglobulins and increased toxicity of antisera to DDHER2 tumor cells. DDHER2 tumor growth was delayed, leading to prolonged survival of the vaccinated vs. naïve BALB/C mice. The PhMV-based anti-HER2 vaccine PhMV-CH401, demonstrated efficacy as an anti-HER2 cancer vaccine. Our studies highlight that VLPs derived from PhMV are a promising platform to develop cancer vaccines.

Metabolic Interdependency of Th2 Cell-Mediated Type 2 Immunity and the Tumor Microenvironment

The function of T cells is critically dependent on their ability to generate metabolic building blocks to fulfil energy demands for proliferation and consecutive differentiation into various T helper (Th) cells. Th cells then have to adapt their metabolism to specific microenvironments within different organs during physiological and pathological immune responses. In this context, Th2 cells mediate immunity to parasites and are involved in the pathogenesis of allergic diseases including asthma, while CD8+ T cells and Th1 cells mediate immunity to viruses and tumors. Importantly, recent studies have investigated the metabolism of Th2 cells in more detail, while others have studied the influence of Th2 cell-mediated type 2 immunity on the tumor microenvironment (TME) and on tumor progression. We here review recent findings on the metabolism of Th2 cells and discuss how Th2 cells contribute to antitumor immunity. Combining the evidence from both types of studies, we provide here for the first time a perspective on how the energy metabolism of Th2 cells and the TME interact. Finally, we elaborate how a more detailed understanding of the unique metabolic interdependency between Th2 cells and the TME could reveal novel avenues for the development of immunotherapies in treating cancer.

Tipping the Scales With Zebrafish to Understand Adaptive Tumor Immunity

The future of improved immunotherapy against cancer depends on an in-depth understanding of the dynamic interactions between the immune system and tumors. Over the past two decades, the zebrafish has served as a valuable model system to provide fresh insights into both the development of the immune system and the etiologies of many different cancers. This well-established foundation of knowledge combined with the imaging and genetic capacities of the zebrafish provides a new frontier in cancer immunology research. In this review, we provide an overview of the development of the zebrafish immune system along with a side-by-side comparison of its human counterpart. We then introduce components of the adaptive immune system with a focus on their roles in the tumor microenvironment (TME) of teleosts. In addition, we summarize zebrafish models developed for the study of cancer and adaptive immunity along with other available tools and technology afforded by this experimental system. Finally, we discuss some recent research conducted using the zebrafish to investigate adaptive immune cell-tumor interactions. Without a doubt, the zebrafish will arise as one of the driving forces to help expand the knowledge of tumor immunity and facilitate the development of improved anti-cancer immunotherapy in the foreseeable future.