The immunosuppressive tumour network: myeloid-derived suppressor cells, regulatory T cells and natural killer T cells

Cancer therapy with the viral and bacterial pathogens: The past enemies can be considered the present allies

Cancer continues to be one of the leading causes of mortality worldwide despite significant advancements in cancer treatment. Many difficulties have arisen as a result of the detrimental consequences of chemotherapy and radiotherapy as a common cancer therapy, such as drug inability to penetrate deep tumor tissue, and also the drug resistance in tumor cells continues to be a major concern. These obstacles have increased the need for the development of new techniques that are more selective and effective against cancer cells. Bacterial-based therapies and the use of oncolytic viruses can suppress cancer in comparison to other cancer medications. The tumor microenvironment is susceptible to bacterial accumulation and proliferation, which can trigger immune responses against the tumor. Oncolytic viruses (OVs) have also gained considerable attention in recent years because of their potential capability to selectively target and induce apoptosis in cancer cells. This review aims to provide a comprehensive summary of the latest literature on the role of bacteria and viruses in cancer treatment, discusses the limitations and challenges, outlines various strategies, summarizes recent preclinical and clinical trials, and emphasizes the importance of optimizing current strategies for better clinical outcomes.

Regulation of anti-tumor immunity by metal ion in the tumor microenvironment

Metal ions play an essential role in regulating the functions of immune cells by transmitting intracellular and extracellular signals in tumor microenvironment (TME). Among these immune cells, we focused on the impact of metal ions on T cells because they can recognize and kill cancer cells and play an important role in immune-based cancer treatment. Metal ions are often used in nanomedicines for tumor immunotherapy. In this review, we discuss seven metal ions related to anti-tumor immunity, elucidate their roles in immunotherapy, and provide novel insights into tumor immunotherapy and clinical applications.

The role of the immunosuppressive PD-1/PD-L1 checkpoint pathway in the aging process and age-related diseases

The accumulation of senescent cells within tissues is a hallmark of the aging process. Senescent cells are also commonly present in many age-related diseases and in the cancer microenvironment. The escape of abnormal cells from immune surveillance indicates that there is some defect in the function of cytotoxic immune cells, e.g., CD8+ T cells and natural killer (NK) cells. Recent studies have revealed that the expression of programmed death-ligand 1 (PD-L1) protein is abundantly increased in senescent cells. An increase in the amount of PD-L1 protein protects senescent cells from clearance by the PD-1 checkpoint receptor in cytotoxic immune cells. In fact, the activation of the PD-1 receptor suppresses the cytotoxic properties of CD8+ T and NK cells, promoting a state of immunosenescence. The inhibitory PD-1/PD-L1 checkpoint pathway acts in cooperation with immunosuppressive cells; for example, activation of PD-1 receptor can enhance the differentiation of regulatory T cells (Treg), myeloid-derived suppressor cells (MDSC), and M2 macrophages, whereas the cytokines secreted by immunosuppressive cells stimulate the expression of the immunosuppressive PD-L1 protein. Interestingly, many signaling pathways known to promote cellular senescence and the aging process are crucial stimulators of the expression of PD-L1 protein, e.g., epigenetic regulation, inflammatory mediators, mTOR-related signaling, cGAS-STING pathway, and AhR signaling. It seems that the inhibitory PD-1/PD-L1 immune checkpoint axis has a crucial role in the accumulation of senescent cells and thus it promotes the aging process in tissues. Thus, the blockade of the PD-1/PD-L1 checkpoint signaling might be a potential anti-aging senolytic therapy. KEY MESSAGES: Senescent cells accumulate within tissues during aging and age-related diseases. Senescent cells are able to escape immune surveillance by cytotoxic immune cells. Expression of programmed death-ligand 1 (PD-L1) markedly increases in senescent cells. Age-related signaling stimulates the expression of PD-L1 protein in senescent cells. Inhibitory PD-1/PD-L1 checkpoint pathway suppresses clearance of senescent cells.

Integrated analysis of colorectal cancer metastasis identifies characteristics of tumor cell during metastasis

Background

Metastasis is the main cause of death in colorectal cancer (CRC). Metastasis is a sequential and dynamic process, but the development of tumor cells during this process is unclear. In this study, we aimed to reveal characteristics of tumor cell subset during CRC metastasis.

Methods

Single-cell RNA sequence CRC data of normal epithelium, non-metastatic primary tumor, metastatic primary tumor, and liver metastases from gene expression omnibus (GEO) dataset were analyzed to reveal characteristics of CRC metastasis. Primary tumor tissues of three non-metastatic CRC and three metastatic CRC patients from Union Hospital of Tongji Medical College (Wuhan, China) were used to verify the characteristics of CRC metastasis.

Results

We identified a metastasis-related cancer cell subset EP1, which was characterized with a high expression of KRT17, LAMC2, EMP1, and PLAC8. EP1 had an enhanced cell-cell interaction, which interacted with SPP+ macrophages and drove them toward anti-inflammatory and immunosuppressive phenotype. Dynamic changes in genes and TF regulons during the metastasis were also revealed.

Conclusions

This study advanced our understanding of the development of tumor cells during CRC metastasis and further identified metastasis-related subset and potential therapeutic targets for the treatment and prevention of CRC metastasis.

Role of Exosomes in Cancer and Aptamer-Modified Exosomes as a Promising Platform for Cancer Targeted Therapy

Exosomes are increasingly recognized as important mediators of intercellular communication in cancer biology. Exosomes can be derived from cancer cells as well as cellular components in tumor microenvironment. After secretion, the exosomes carrying a wide range of bioactive cargos can be ingested by local or distant recipient cells. The released cargos act through a variety of mechanisms to elicit multiple biological effects and impact most if not all hallmarks of cancer. Moreover, owing to their excellent biocompatibility and capability of being easily engineered or modified, exosomes are currently exploited as a promising platform for cancer targeted therapy. In this review, we first summarize the current knowledge of roles of exosomes in risk and etiology, initiation and progression of cancer, as well as their underlying molecular mechanisms. The aptamer-modified exosome as a promising platform for cancer targeted therapy is then briefly introduced. We also discuss the future directions for emerging roles of exosome in tumor biology and perspective of aptamer-modified exosomes in cancer therapy.

LC3-dependent extracellular vesicles promote M-MDSC accumulation and immunosuppression in colorectal cancer

For a long time, myeloid-derived suppressor cells (MDSCs) dilated in circulation system of colorectal cancer (CRC) patients have been puzzling clinicians. Various evidence shows that MDSCs constitute the bulk of immunosuppression in CRC, which is related to tumor growth, adhesion, invasion, metastasis, and immune escape. However, the mechanisms underlying these cells formation remain incompletely understood. In this study, we reported that CRC cell-derived LC3-dependent extracellular vesicles (LDEVs)-mediated M-MDSCs formation via TLR2-MYD88 pathway. Furthermore Hsp60 was the LDEVs surface ligand that triggered these MDSCs induction. In clinical studies, we reported that accumulation of circulating M-MDSCs as well as IL-10 and arginase1 secretion were reliant upon the levels of tumor cell-derived LDEVs in CRC patients. These findings indicated how local tumor cell-derived extracellular vesicles influence distal hematopoiesis and provided novel justification for therapeutic targeting of LDEVs in patients with CRC.

PAD4 Inhibitor-Functionalized Layered Double Hydroxide Nanosheets for Synergistic Sonodynamic Therapy/Immunotherapy Of Tumor Metastasis

Sonodynamic therapy (SDT) is demonstrated to trigger the systemic immune response of the organism and facilitate the treatment of metastatic tumors. However, SDT-mediated neutrophil extracellular traps (NETs) formation can promote tumor cell spread, thus weakening the therapeutic effectiveness of metastatic tumors. Herein, the amorphous CoW-layered double hydroxide (a-CoW-LDH) nanosheets are functionalized with a peptidyl arginine deiminase 4 (PAD4) inhibitor, i.e., YW3-56, to construct a multifunctional nanoagent (a-LDH@356) for synergistic SDT/immunotherapy. Specifically, a-CoW-LDH nanosheets can act as a sonosensitizer to generate abundant reactive oxygen species (ROS) under US irradiation. After loading with YW3-56, a-LDH@356 plus US irradiation not only effectively induces ROS generation and immunogenic cell death, but also inhibits the elevation of citrullinated histone H3 (H3cit) and the release of NETs, enabling a synergistic enhancement of anti-tumor metastasis effect. Using 4T1 tumor model, it is demonstrated that combining a-CoW-LDH with YW3-56 stimulates an anti-tumor response by upregulating the proportion of immune-activated cells and inducing polarization of M1 macrophages, and inhibits immune escape by downregulating the expression of PD-1 on immune cells under US irradiation, which not only arrests primary tumor progression with a tumor inhibition rate of 69.5% but also prevents tumor metastasis with the least number of lung metastatic nodules.

H2 antihistamines: May be useful for combination therapies in cancer?

Cancer morbimortality is still a great concern despite advances in research and therapies. Histamine and its receptors' ligands can modulate different biological responses according to the cell type and the receptor subtype involved. Besides the wide variety of histamine functions in normal tissues, diverse roles in the acquisition of hallmarks of cancer such as sustained proliferative signaling, resistance to cell death, angiogenesis, metastasis, altered immunity and modified microenvironment have been described. This review summarizes the present knowledge of the various roles of histamine H2 receptor (H2R) ligands in neoplasias. A bioinformatic analysis of human tumors showed dissimilar results in the expression of the H2R gene according to tumor type when comparing malignant versus normal tissues. As well, the relationship between patients' survival parameters and H2R gene expression levels also varied, signaling important divergences in the role of H2R in neoplastic progression in different cancer types. Revised experimental evidence showed multiple effects of H2R antihistamines on several of the cited hallmarks of cancer. Interventional and retrospective clinical studies evaluated different H2R antihistamines in cancer patients with two main adjuvant uses: improving antitumor efficacy (which includes regulation of immune response) and preventing toxic adverse effects produced by chemo or radiotherapy. While there is a long path to go, research on H2R antihistamines may provide new opportunities for developing more refined combination therapeutic strategies for certain cancer types to improve patients' survival and health-related quality of life.

Single-cell profiling reveals the metastasis-associated immune signature of hepatocellular carcinoma

AIM

Metastasis is the leading cause of mortality in hepatocellular carcinoma (HCC). The metastasis-associated immune signature in HCC is worth exploring.

METHODS

Bioinformatic analysis was conducted based on the single-cell transcriptome data derived from HCC patients in different stages. Cellular composition, pseudotime state transition, and cell-cell interaction were further analyzed and verified.

RESULTS

Generally, HCC with metastasis exhibited suppressive immune microenvironment, while HCC without metastasis exhibited active immune microenvironment. Concretely, effector regulatory T cells (eTregs) were found to be enriched in HCC with metastasis. PHLDA1 was identified as one of exhaustion-specific genes and verified to be associated with worse prognosis in HCC patients. Moreover, A novel cluster of CCR7+ dendritic cells (DCs) was identified with high expression of maturation and migration marker genes. Pseudotime analysis showed that inhibition of differentiation occurred in CCR7+ DCs rather than cDC1 in HCC with metastasis. Furthermore, interaction analysis showed that the reduction of CCR7+ DCs lead to impaired CCR7/CCL19 interaction in HCC with metastasis.

CONCLUSIONS

HCC with metastasis exhibited upregulation of exhaustion-specific genes of eTregs and inhibition of CCL signal of a novel DC cluster, which added new dimensions to the immune landscape and provided new immune therapeutic targets in advanced HCC.

Nanozymes with biomimetically designed properties for cancer treatment

Nanozymes, as a type of nanomaterials with enzymatic catalytic activity, have demonstrated tremendous potential in cancer treatment owing to their unique biomedical properties. However, the heterogeneity of tumors and the complex tumor microenvironment pose significant challenges to the in vivo catalytic efficacy of traditional nanozymes. Drawing inspiration from natural enzymes, scientists are now using biomimetic design to build nanozymes from the ground up. This approach aims to replicate the key characteristics of natural enzymes, including active structures, catalytic processes, and the ability to adapt to the tumor environment. This achieves selective optimization of nanozyme catalytic performance and therapeutic effects. This review takes a deep dive into the use of these biomimetically designed nanozymes in cancer treatment. It explores a range of biomimetic design strategies, from structural and process mimicry to advanced functional biomimicry. A significant focus is on tweaking the nanozyme structures to boost their catalytic performance, integrating them into complex enzyme networks similar to those in biological systems, and adjusting functions like altering tumor metabolism, reshaping the tumor environment, and enhancing drug delivery. The review also covers the applications of specially designed nanozymes in pan-cancer treatment, from catalytic therapy to improved traditional methods like chemotherapy, radiotherapy, and sonodynamic therapy, specifically analyzing the anti-tumor mechanisms of different therapeutic combination systems. Through rational design, these biomimetically designed nanozymes not only deepen the understanding of the regulatory mechanisms of nanozyme structure and performance but also adapt profoundly to tumor physiology, optimizing therapeutic effects and paving new pathways for innovative cancer treatment.

ΔNp63 regulates MDSC survival and metabolism in triple-negative breast cancer

Triple-negative breast cancer (TNBC) contributes greatly to mortality of breast cancer, demanding new targetable options. We have shown that TNBC patients have high ΔNp63 expression in tumors. However, the function of ΔNp63 in established TNBC is yet to be explored. In current studies, targeting ΔNp63 with inducible CRISPR knockout and Histone deacetylase inhibitor Quisinostat showed that ΔNp63 is important for tumor progression and metastasis in established tumors by promoting myeloid-derived suppressor cell (MDSC) survival through tumor necrosis factor alpha. Decreasing ΔNp63 levels are associated with decreased CD4+ and FOXP3+ T-cells but increased CD8+ T-cells. RNA sequencing analysis indicates that loss of ΔNp63 alters multiple MDSC properties such as lipid metabolism, chemotaxis, migration, and neutrophil degranulation besides survival. We further demonstrated that targeting ΔNp63 sensitizes chemotherapy. Overall, we showed that ΔNp63 reprograms the MDSC-mediated immunosuppressive functions in TNBC, highlighting the benefit of targeting ΔNp63 in chemotherapy-resistant TNBC.

Tumor Immune Microenvironment and Its Clinicopathological and Prognostic Associations in Canine Splenic Hemangiosarcoma

Tumor cells can induce important cellular and molecular modifications in the tissue or host where they grow. The idea that the host and tumor interact with each other has led to the concept of a tumor microenvironment, composed of immune cells, stromal cells, blood vessels, and extracellular matrix, representing a unique environment participating and, in some cases, promoting cancer progression. The study of the tumor immune microenvironment, particularly focusing on the role of tumor-infiltrating lymphocytes (TILs), is highly relevant in oncology due to the prognostic and therapeutic significance of TILs in various tumors and their identification as targets for therapeutic intervention. Canine splenic hemangiosarcoma (HSA) is a common tumor; however, its immune microenvironment remains poorly understood. This retrospective study aimed to characterize the histological and immunohistochemical features of 56 cases of canine splenic HSA, focusing particularly on tumor-infiltrating lymphocytes (TILs). We assessed the correlations between the lymphocytic response, the macroscopic and histological characteristics of the tumor, and the survival data. Our study demonstrated that FoxP3 distribution was associated with tumor-related death and survival, while the CD20 count was associated with metastasis. This study provides an in-depth characterization of the tumor immune microenvironment in canine splenic HSA and describes potential prognostic factors.

Unraveling the tumor microenvironment: Insights into cancer metastasis and therapeutic strategies

This comprehensive review delves into the pivotal role of the tumor microenvironment (TME) in cancer metastasis and therapeutic response, offering fresh insights into the intricate interplay between cancer cells and their surrounding milieu. The TME, a dynamic ecosystem comprising diverse cellular and acellular elements, not only fosters tumor progression but also profoundly affects the efficacy of conventional and emerging cancer therapies. Through nuanced exploration, this review illuminates the multifaceted nature of the TME, elucidating its capacity to engender drug resistance via mechanisms such as hypoxia, immune evasion, and the establishment of physical barriers to drug delivery. Moreover, it investigates innovative therapeutic approaches aimed at targeting the TME, including stromal reprogramming, immune microenvironment modulation, extracellular matrix (ECM)-targeting agents, and personalized medicine strategies, highlighting their potential to augment treatment outcomes. Furthermore, this review critically evaluates the challenges posed by the complexity and heterogeneity of the TME, which contribute to variable therapeutic responses and potentially unintended consequences. This underscores the need to identify robust biomarkers and advance predictive models to anticipate treatment outcomes, as well as advocate for combination therapies that address multiple facets of the TME. Finally, the review emphasizes the necessity of an interdisciplinary approach and the integration of cutting-edge technologies to unravel the intricacies of the TME, thereby facilitating the development of more effective, adaptable, and personalized cancer treatments. By providing critical insights into the current state of TME research and its implications for the future of oncology, this review highlights the dynamic and evolving landscape of this field.

Molecular insights into clinical trials for immune checkpoint inhibitors in colorectal cancer: Unravelling challenges and future directions

Colorectal cancer (CRC) is a complex disease with diverse etiologies and clinical outcomes. Despite considerable progress in development of CRC therapeutics, challenges remain regarding the diagnosis and management of advanced stage metastatic CRC (mCRC). In particular, the five-year survival rate is very low since mCRC is currently rarely curable. Over the past decade, cancer treatment has significantly improved with the introduction of cancer immunotherapies, specifically immune checkpoint inhibitors. Therapies aimed at blocking immune checkpoints such as PD-1, PD-L1, and CTLA-4 target inhibitory pathways of the immune system, and thereby enhance anti-tumor immunity. These therapies thus have shown promising results in many clinical trials alone or in combination. The efficacy and safety of immunotherapy, either alone or in combination with CRC, have been investigated in several clinical trials. Clinical trials, including KEYNOTE-164 and CheckMate 142, have led to Food and Drug Administration approval of the PD-1 inhibitors pembrolizumab and nivolumab, respectively, for the treatment of patients with unresectable or metastatic microsatellite instability-high or deficient mismatch repair CRC. Unfortunately, these drugs benefit only a small percentage of patients, with the benefits of immunotherapy remaining elusive for the vast majority of CRC patients. To this end, primary and secondary resistance to immunotherapy remains a significant issue, and further research is necessary to optimize the use of immunotherapy in CRC and identify biomarkers to predict the response. This review provides a comprehensive overview of the clinical trials involving immune checkpoint inhibitors in CRC. The underlying rationale, challenges faced, and potential future steps to improve the prognosis and enhance the likelihood of successful trials in this field are discussed.

A Defect-Engineered Nanozyme for Targeted NIR-II Photothermal Immunotherapy of Cancer

Multienzyme-mimicking redox nanozymes, curated by defect engineering, in synergy with immunotherapy offer promising prospects for safe and efficient cancer therapy. However, the spatiotemporally precise immune response often gets challenged by off-target adverse effects and insufficient therapeutic response. Herein, a tumor cell membrane coated redox nanozyme (CMO-R@4T1) is reported for combinational second near-infrared window (NIR-II) photothermal immunotherapy. CMO-R@4T1 consists of a Cu-doped MoOx (CMO) nanozyme as the core, which is cloaked with tumor-cell-derived fused membranes with immunostimulants immobilized in the membrane shell. In addition to the enhanced tumor accumulation, the nanozyme can cause oxidative damage to tumor cells by the production of reactive oxygen species and attenuation of the antioxidant mechanism. CMO-R@4T1 also mediates a photothermal effect under NIR-II photoirradiation to trigger tumor eradication and immunogenic cell death, where the liberated agonist elicits the immune activation. Such a controlled therapeutic paradigm potentiates systemic primary tumor ablation, inhibits cancer metastasis to distant tumor, and procures long-term immunological memory. Thereby, this study takes advantage of defect engineering to illustrate a generic strategy to prepare cell-membrane-camouflaged nanozymes for targeted photo-immunotherapy of cancer.

Anti-TIGIT antibody improves PD-L1 blockade through myeloid and Treg cells

Tiragolumab, an anti-TIGIT antibody with an active IgG1κ Fc, demonstrated improved outcomes in the phase 2 CITYSCAPE trial (ClinicalTrials.gov: NCT03563716 ) when combined with atezolizumab (anti-PD-L1) versus atezolizumab alone1. However, there remains little consensus on the mechanism(s) of response with this combination2. Here we find that a high baseline of intratumoural macrophages and regulatory T cells is associated with better outcomes in patients treated with atezolizumab plus tiragolumab but not with atezolizumab alone. Serum sample analysis revealed that macrophage activation is associated with a clinical benefit in patients who received the combination treatment. In mouse tumour models, tiragolumab surrogate antibodies inflamed tumour-associated macrophages, monocytes and dendritic cells through Fcγ receptors (FcγR), in turn driving anti-tumour CD8+ T cells from an exhausted effector-like state to a more memory-like state. These results reveal a mechanism of action through which TIGIT checkpoint inhibitors can remodel immunosuppressive tumour microenvironments, and suggest that FcγR engagement is an important consideration in anti-TIGIT antibody development.

Measuring the composition of the tumor microenvironment with transcriptome analysis: past, present and future

Interactions between tumor cells and immune cells in the tumor microenvironment (TME) play a vital role the mechanisms of immune evasion, by which cancer cells escape immune elimination. Thus, the characterization and quantification of different components in the TME is a hot topic in molecular biology and drug discovery. Since the development of transcriptome sequencing in bulk tissue, single cells and spatial dimensions, there are increasing methods emerging to deconvolute and subtype the TME. This review discusses and compares such computational strategies and downstream subtyping analyses. Integrative analyses of the transcriptome with other data, such as epigenetics and T-cell receptor sequencing, are needed to obtain comprehensive knowledge of the dynamic TME.

Correlation of Myeloid-Derived Suppressor Cell Expansion with Upregulated Transposable Elements in Severe COVID-19 Unveiled in Single-Cell RNA Sequencing Reanalysis

Some studies have investigated the potential role of transposable elements (TEs) in COVID-19 pathogenesis and complications. However, to the best of our knowledge, there is no study to examine the possible association of TE expression in cell functions and its potential role in COVID-19 immune response at the single-cell level. In this study, we reanalyzed single-cell RNA seq data of bronchoalveolar lavage (BAL) samples obtained from six severe COVID-19 patients and three healthy donors to assess the probable correlation of TE expression with the immune responses induced by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) in COVID-19 patients. Our findings indicate that the expansion of myeloid-derived suppressor cells (MDSCs) may be a characteristic feature of COVID-19. Additionally, a significant increase in TE expression in MDSCs was observed. This upregulation of TEs in COVID-19 may be linked to the adaptability of these cells in response to their microenvironments. Furthermore, it appears that the identification of overexpressed TEs by pattern recognition receptors (PRRs) in MDSCs may enhance the suppressive capacity of these cells. Thus, this study emphasizes the crucial role of TEs in the functionality of MDSCs during COVID-19.

Expansion of distinct peripheral blood myeloid cell subpopulations in patients with rheumatoid arthritis-associated interstitial lung disease

OBJECTIVES

Interstitial lung disease (ILD) is associated with significant mortality in rheumatoid arthritis (RA) patients with key cellular players remaining largely unknown. This study aimed to characterize inflammatory and myeloid derived suppressor cell (MDSC) subpopulations in RA-ILD as compared to RA, idiopathic pulmonary fibrosis (IPF) without autoimmunity, and controls.

METHODS

Peripheral blood was collected from patients with RA, RA-ILD, IPF, and controls (N = 60, 15/cohort). Myeloid cell subpopulations were identified phenotypically by flow cytometry using the following markers:CD45,CD3,CD19,CD56,CD11b,HLA-DR,CD14,CD16,CD15,CD125,CD33. Functionality of subsets were identified with intracellular arginase-1 (Arg-1) and inducible nitric oxide synthase (iNOS) expression.

RESULTS

There was increased intermediate (CD14++CD16+) and nonclassical (CD14+/-CD16++) and decreased classical (CD14++CD16-) monocytes in RA, RA-ILD, and IPF vs. control. Intermediate monocytes were higher and classical monocytes were lower in RA-ILD vs. RA but not IPF. Monocytic (m)MDSCs were higher in RA-ILD vs. control and RA but not IPF. Granulocytic (g)MDSCs did not significantly differ. In contrast, neutrophils were increased in IPF and RA-ILD patients with elevated expression of Arg-1 sharing similar dimensional clustering pattern. Eosinophils were increased in RA-ILD vs. controls, RA and IPF. Across cohorts, iNOS was decreased in intermediate/nonclassical monocytes but increased in mMDSCs vs. classical monocytes. In RA-ILD, iNOS positive mMDSCs were increased versus classic monocytes.

CONCLUSIONS

Myeloid cell subpopulations are significantly modulated in RA-ILD patients with expansion of CD16+ monocytes, mMDSCs, and neutrophils, a phenotypic profile more aligned with IPF than other RA patients. Eosinophil expansion was unique to RA-ILD, potentially facilitating disease pathogenesis and providing a future therapeutic target.

Experimental and clinical evidence in favour of an effective immune stimulation in ER-positive, endocrine-dependent metastatic breast cancer

In ER+ breast cancer, usually seen as the low immunogenic type, the main mechanisms favouring the immune response or tumour growth and immune evasion in the tumour microenvironment (TME) have been examined. The principal implications of targeting the oestrogen-mediated pathways were also considered. Recent experimental findings point out that anti-oestrogens contribute to the reversion of the immunosuppressive TME. Moreover, some preliminary clinical data with the hormone-immunotherapy association in a metastatic setting support the notion that the reversion of immune suppression in TME is likely favoured by the G0-G1 state induced by anti-oestrogens. Following immune stimulation, the reverted immune suppression allows the boosting of the effector cells of the innate and adaptive immune response. This suggests that ER+ breast cancer is a molecular subtype where a successful active immune manipulation can be attained. If this is confirmed by a prospective multicentre trial, which is expected in light of the provided evidence, the proposed hormone immunotherapy can also be tested in the adjuvant setting. Furthermore, the different rationale suggests a synergistic activity of our proposed immunotherapy with the currently recommended regimen consisting of antioestrogens combined with cyclin kinase inhibitors. Overall, this lays the foundation for a shift in clinical practice within this most prevalent molecular subtype of breast cancer.

Biophysical Control of the Glioblastoma Immunosuppressive Microenvironment: Opportunities for Immunotherapy

GBM is the most aggressive and common form of primary brain cancer with a dismal prognosis. Current GBM treatments have not improved patient survival, due to the propensity for tumor cell adaptation and immune evasion, leading to a persistent progression of the disease. In recent years, the tumor microenvironment (TME) has been identified as a critical regulator of these pro-tumorigenic changes, providing a complex array of biomolecular and biophysical signals that facilitate evasion strategies by modulating tumor cells, stromal cells, and immune populations. Efforts to unravel these complex TME interactions are necessary to improve GBM therapy. Immunotherapy is a promising treatment strategy that utilizes a patient's own immune system for tumor eradication and has exhibited exciting results in many cancer types; however, the highly immunosuppressive interactions between the immune cell populations and the GBM TME continue to present challenges. In order to elucidate these interactions, novel bioengineering models are being employed to decipher the mechanisms of immunologically "cold" GBMs. Additionally, these data are being leveraged to develop cell engineering strategies to bolster immunotherapy efficacy. This review presents an in-depth analysis of the biophysical interactions of the GBM TME and immune cell populations as well as the systems used to elucidate the underlying immunosuppressive mechanisms for improving current therapies.

Navigating the Immune Maze: Pioneering Strategies for Unshackling Cancer Immunotherapy Resistance

Cancer immunotherapy has ushered in a transformative era in oncology, offering unprecedented promise and opportunities. Despite its remarkable breakthroughs, the field continues to grapple with the persistent challenge of treatment resistance. This resistance not only undermines the widespread efficacy of these pioneering treatments, but also underscores the pressing need for further research. Our exploration into the intricate realm of cancer immunotherapy resistance reveals various mechanisms at play, from primary and secondary resistance to the significant impact of genetic and epigenetic factors, as well as the crucial role of the tumor microenvironment (TME). Furthermore, we stress the importance of devising innovative strategies to counteract this resistance, such as employing combination therapies, tailoring immune checkpoints, and implementing real-time monitoring. By championing these state-of-the-art methods, we anticipate a paradigm that blends personalized healthcare with improved treatment options and is firmly committed to patient welfare. Through a comprehensive and multifaceted approach, we strive to tackle the challenges of resistance, aspiring to elevate cancer immunotherapy as a beacon of hope for patients around the world.

Esophageal cancer cell-derived small extracellular vesicles decrease circulating Tfh/Tfr via sEV-PDL1 to promote immunosuppression

Esophageal cancer (EC) is a deadly malignancy. Small extracellular vesicles (sEVs) with programmed death ligand 1 (sEV-PDL1) induce immune escape to promote tumor progression. Furthermore, the imbalance between circulating follicular helper T (Tfh) and circulating follicular regulatory T (Tfr) cells is related to the progression of many malignant tumors. However, the role of the EC-derived sEV-PDL1 in circulating Tfh/Tfr is unknown. Circulating Tfh and Tfr cells were detected by flow cytometry. sEVs were isolated through differential centrifugation and cultured for cell expansion assays. Naïve CD4+ T cells were isolated, stimulated, and cultured with sEVs to evaluate the frequencies, phenotypes, and functions of Tfh and Tfr cells. The proportion of circulating Tfh in patients with EC was lower than that in healthy donors (HDs), whereas that of circulating Tfr was higher. The EC group showed significantly lower circulating Tfh/Tfr and a higher level of sEV-PDL1 than HDs. Notably, sEV-PDL1 was negatively correlated with circulating Tfh/Tfr in the EC group. In vitro assays, sEV-PDL1 inhibited Tfh expansion, enhanced the cytotoxic T lymphocyte-associated antigen 4+ (CTLA4+) Tfh cell percentage, decreased the levels of interleukin (IL)-21 and interferon-γ, and increased IL-10. sEV-PDL1 promoted the expansion and immunosuppressive functions of circulating Tfr; the increased percentages of CTLA4+ Tfr and inducible T cell co-stimulator+ Tfr were accompanied with high IL-10. However, applying an anti-PDL1 antibody significantly reversed this. Our results suggest a novel mechanism of sEV-PDL1-mediated immunosuppression in EC. Inhibiting sEV-PDL1 to restore circulating Tfh/Tfr balance provides a novel therapeutic approach for EC.

Journey of CAR T‑cells: Emphasising the concepts and advancements in breast cancer (Review)

Cancer is the primary and one of the most prominent causes of the rising global mortality rate, accounting for nearly 10 million deaths annually. Specific methods have been devised to cure cancerous tumours. Effective therapeutic approaches must be developed, both at the cellular and genetic level. Immunotherapy offers promising results by providing sustained remission to patients with refractory malignancies. Genetically modified T‑lymphocytic cells have emerged as a novel therapeutic approach for the treatment of solid tumours, haematological malignancies, and relapsed/refractory B‑lymphocyte malignancies as a result of recent clinical trial findings; the treatment is referred to as chimeric antigen receptor T‑cell therapy (CAR T‑cell therapy). Leukapheresis is used to remove T‑lymphocytes from the leukocytes, and CARs are created through genetic engineering. Without the aid of a major histocompatibility complex, these genetically modified receptors lyse malignant tissues by interacting directly with the carcinogen. Additionally, the outcomes of preclinical and clinical studies reveal that CAR T‑cell therapy has proven to be a potential therapeutic contender against metastatic breast cancer (BCa), triple‑negative, and HER 2+ve BCa. Nevertheless, unique toxicities, including (cytokine release syndrome, on/off‑target tumour recognition, neurotoxicities, anaphylaxis, antigen escape in BCa, and the immunosuppressive tumour microenvironment in solid tumours, negatively impact the mechanism of action of these receptors. In this review, the potential of CAR T‑cell immunotherapy and its method of destroying tumour cells is explored using data from preclinical and clinical trials, as well as providing an update on the approaches used to reduce toxicities, which may improve or broaden the effectiveness of the therapies used in BCa.

Immune checkpoint targeting antibodies hold promise for combinatorial cancer therapeutics

Through improving the immune system's ability to recognize and combat tumor cells as well as its receptivity to changes in the tumor microenvironment, immunotherapy has emerged as a highly successful addition to the treatment of cancer. However, tumor heterogeneity poses a significant challenge in cancer therapy as it can undermine the anti-tumor immune response through the manipulation of the extracellular matrix. To address these challenges and improve targeted therapies and combination treatments, the food and drug administration has approved several immunomodulatory antibodies to suppress immunological checkpoints. Combinatorial therapies necessitate the identification of multiple targets that regulate the intricate communication between immune cells, cytokines, chemokines, and cellular responses within the tumor microenvironment. The purpose of this study is to provide a comprehensive overview of the ongoing clinical trials involving immunomodulatory antibodies in various cancer types. It explores the potential of these antibodies to modulate the immune system and enhance anti-tumor responses. Additionally, it discusses the perspectives and prospects of immunomodulatory therapeutics in cancer treatment. Although immunotherapy shows great promise in cancer treatment, it is not exempt from side effects that can arise due to hyperactivity of the immune system. Therefore, understanding the intricate balance between immune activation and regulation is crucial for minimizing these adverse effects and optimizing treatment outcomes. This study aims to contribute to the growing body of knowledge surrounding immunomodulatory antibodies and their potential as effective therapeutic options in cancer treatment, ultimately paving the way for improved patient outcomes and deepening our perception of the intricate interactivity between the immune system and tumors.

GPC3-IL7-CCL19-CAR-T primes immune microenvironment reconstitution for hepatocellular carcinoma therapy

BACKGROUND

Chimeric antigen receptor (CAR)-T-cell therapy is a revolutionary treatment that has become a mainstay of advanced cancer treatment. Conventional glypican-3 (GPC3)-CAR-T cells have not produced ideal clinical outcomes in advanced hepatocellular carcinoma (HCC), and the mechanism is unclear. This study aims to investigate the clinical utility of novel GPC3-7-19-CAR-T cells constructed by our team and to explore the mechanisms underlying their antitumor effects.

METHODS

We engineered a novel GPC3-targeting CAR including an anti-GPC3 scFv, CD3ζ, CD28 and 4-1BB that induces co-expression of IL-7 at a moderate level (500 pg/mL) and CCL19 at a high level (15000 pg /mL) and transduced it into human T cells. In vitro, cell killing efficacy was validated by the xCELLigence RTCA system, LDH nonradioactive cytotoxicity assay and was confirmed in primary HCC organoid models employing a 3D microfluid chip. In vivo, the antitumor capacity was assessed in a humanized NSG mouse xenograft model. Finally, we initiated a phase I clinical trial to evaluate the safety and effect of GPC3-7-19-CAR-T cells in the clinic.

RESULTS

GPC3-7-19-CAR-T cells had 1.5-2 times higher killing efficiency than GPC3-CAR-T cells. The tumor formation rates in GPC3-7-19-CAR-T cells treated model were reduced (3/5vs.5/5), and the average tumor volumes were 0.74 cm3 ± 1.17 vs. 0.34 cm3 ± 0.25. Of note, increased proportion of CD4+ TEM and CD8+ TCM cells was infiltrated in GPC3-7-19-CAR-T cells group. GPC3-7-19-CAR-T cells obviously reversed the immunosuppressive tumor microenvironment (TME) by reducing polymorphonuclear (PMN)-myeloid-derived suppressor cells (MDSCs) and regulatory T (Treg) cells infiltration and recruiting more dendritic cells (DCs) to HCC xenograft tumor tissues. In one patient with advanced HCC, GPC3-7-19-CAR-T-cell treatment resulted in tumor reduction 56 days after intravenous infusion.

CONCLUSIONS

In conclusion, GPC3-7-19-CAR-T cells achieved antitumor effects superior to those of conventional GPC3-CAR-T cells by reconstructing the TME induced by the dominant CD4+ TEM and CD8+ TCM cell subsets. Most importantly, GPC3-7-19-CAR-T cells exhibited good safety and antitumor efficacy in HCC patients in the clinic. ► Novel GPC3-7-19-CAR-T cells designed with mediate level of IL-7 secretion and high level of CCL19 secretion, which could recruit more mature DCs to assist killing on GPC3+HCCs. ►DC cells recruited by CCL19 could interact with CD4+ T cells and promote the differentiation of CD4+TEFF cells into CD4+TEM and CD8+TCM subsets, leading a better anti-tumor effect on GPC3+HCCs. ►Compared with conventional GPC3-CAR-T, GPC3-7-CCL19-CAR-T cells could reverse tumor immunosuppressive microenvironment by reducing PMN-MDSC and Treg cell infiltration.

Elsayed A, López-Berestein G, Amero P, Rodríguez-Aguayo C. An Overview of the Immune Modulatory Properties of Long Non-Coding RNAs and Their Potential Use as Therapeutic Targets in Cancer

Long non-coding RNAs (lncRNAs) play pivotal roles in regulating immune responses, immune cell differentiation, activation, and inflammatory processes. In cancer, they are gaining prominence as potential therapeutic targets due to their ability to regulate immune checkpoint molecules and immune-related factors, suggesting avenues for bolstering anti-tumor immune responses. Here, we explore the mechanistic insights into lncRNA-mediated immune modulation, highlighting their impact on immunity. Additionally, we discuss their potential to enhance cancer immunotherapy, augmenting the effectiveness of immune checkpoint inhibitors and adoptive T cell therapies. LncRNAs as therapeutic targets hold the promise of revolutionizing cancer treatments, inspiring further research in this field with substantial clinical implications.

Immunosenescence and Inflammaging in COVID-19

Despite knowledge gaps in understanding the full spectrum of the hyperinflammatory phase caused by SARS-CoV-2, according to the World Health Organization (WHO), COVID-19 is still the leading cause of death worldwide. Susceptible people to severe COVID-19 are those with underlying medical conditions or those with dysregulated and senescence-associated immune responses. As the immune system undergoes aging in the elderly, such drastic changes predispose them to various diseases and affect their responsiveness to infections, as seen in COVID-19. At-risk groups experience poor prognosis in terms of disease recovery. Changes in the quantity and quality of immune cell function have been described in numerous literature sites. Impaired immune cell function along with age-related metabolic changes can lead to features such as hyperinflammatory response, immunosenescence, and inflammaging in COVID-19. Inflammaging is related to the increased activity of the most inflammatory factors and is the main cause of age-related diseases and tissue failure in the elderly. Since hyperinflammation is a common feature of most severe cases of COVID-19, this pathway, which is not fully understood, leads to immunosenescence and inflammaging in some individuals, especially in the elderly and those with comorbidities. In this review, we shed some light on the age-related abnormalities of innate and adaptive immune cells and how hyperinflammatory immune responses contribute to the inflammaging process, leading to clinical deterioration. Further, we provide insights into immunomodulation-based therapeutic approaches, which are potentially important considerations in vaccine design for elderly populations.

Myeloid-derived suppressor cells as a potential biomarker for recurrent pregnancy loss and recurrent implantation failure: Increased levels of MDSCs in recurrent reproductive failure

PROBLEM

Recurrent pregnancy loss (RPL) and recurrent implantation failure (RIF) represent distinct clinical conditions with established definitions, both of which have been linked to an underlying pro-inflammatory state. This study aimed to explore the levels of monocytic-myeloid-derived suppressor cells (M-MDSCs) and regulatory T cells (TReg ) in a cohort of RPL and RIF women and their potential contribution to RPL and RIF.

METHOD OF STUDY

One hundred and eight non-pregnant women were evaluated: 40 RPL, 41 RIF, and 27 fertile healthy controls (HC). A multiparametric flow cytometry approach was utilized to measure and quantify the frequency of M-MDSCs and TReg cells. Cytokine levels in plasma samples were evaluated through a multiplex assay. M-MDSCs levels were significantly higher in RPL and RIF patients compared to HC.

RESULTS

M-MDSCs levels were significantly higher in RPL (9.4% [7-11.6]) and RIF (8.1% [5.9-11.6]) patients compared to HC (6% [4.2-7.6]). An optimal cut-off of 6.1% for M-MDSCs disclosed a sensitivity of 75.6% and 89.7% and a specificity of 57.7% and 57.7% in RIF and RPL groups, respectively. A significant negative correlation was observed between M-MDSCs and TReg (p = .002, r = -.51).

CONCLUSIONS

Our preliminary data allowed us to build a predictive model that may aid as a potential diagnostic tool in the clinic. These findings could provide a better understanding of these pathologies and a better definition of patients that could benefit from personalized treatments to promote pregnancy. Additional exploration and confirmation in distinct study groups are needed to fully assess the diagnostic capabilities of this biomarker.

GK-1 effectively reduces angiogenesis and prevents T cell exhaustion in a breast cancer murine experimental model

Breast cancer is the leading malignancy in women worldwide, both in terms of incidence and mortality. Triple-negative breast cancer (TNBC) is the type with the worst clinical outcomes and with fewer therapeutic options than other types of breast cancer. GK-1 is a peptide that in the experimental model of the metastatic 4T1 breast cancer has demonstrated anti-tumor and anti-metastatic properties. Herein, GK-1 (5 mg/kg, i.v.) weekly administrated not only decreases tumor growth and the number of lung macro-metastases but also lung and lymph nodes micro-metastases. Histological analysis reveals that GK-1 reduced 57% of the intra-tumor vascular areas, diminished the leukemoid reaction's progression, and the spleens' weight and length. A significant reduction in VEGF-C, SDF-1, angiopoietin-2, and endothelin-1 angiogenic factors was induced. Moreover, GK-1 prevents T cell exhaustion in the tumor-infiltrating lymphocytes (TILs) decreasing PD-1 expression. It also increased IFN-γ and granzyme-B expression and the cytotoxic activity of CD8+ TILs cells against tumor cells. All these features were found to be associated with a better antitumor response and prognosis. Altogether, these results reinforce the potential of GK-1 to improve the clinical outcome of triple-negative breast cancer immunotherapy. Translation research is ongoing towards its evaluation in humans.

Constitutive Interleukin-7 Cytokine Signaling Enhances the Persistence of Epstein-Barr Virus-Specific T-Cells

The efficacy of therapeutic T-cells is limited by a lack of positive signals and excess inhibitory signaling in tumor microenvironments. We previously showed that a constitutively active IL7 receptor (C7R) enhanced the persistence, expansion, and anti-tumor activity of T-cells expressing chimeric antigen receptors (CARs), and C7R-modified GD2.CAR T-cells are currently undergoing clinical trials. To determine if the C7R could also enhance the activity of T-cells recognizing tumors via their native T-cell receptors (TCRs), we evaluated its effects in Epstein-Barr virus (EBV)-specific T-cells (EBVSTs) that have produced clinical benefits in patients with EBV-associated malignancies. EBVSTs were generated by stimulation of peripheral blood T-cells with overlapping peptide libraries spanning the EBV lymphoma antigens, LMP1, LMP2, and EBNA 1, followed by retroviral vector transduction to express the C7R. The C7R increased STAT5 signaling in EBVSTs and enhanced their expansion over 30 days of culture in the presence or absence of exogenous cytokines. C7R-EBVSTs maintained EBV antigen specificity but were dependent on TCR stimulation for continued expansion. C7R-EBVSTs produced more rapid lymphoma control in a murine xenograft model than unmodified EBVSTs and persisted for longer. The findings have led to a clinical trial, evaluating C7R-EBVSTs for the treatment of refractory or relapsed EBV-positive lymphoma (NCT04664179).

Advancements in dendritic cell vaccination: enhancing efficacy and optimizing combinatorial strategies for the treatment of glioblastoma

Glioblastomas (GBM) are highly invasive, malignant primary brain tumors. The overall prognosis is poor, and management of GBMs remains a formidable challenge, necessitating novel therapeutic strategies such as dendritic cell vaccinations (DCVs). While many early clinical trials demonstrate an induction of an antitumoral immune response, outcomes are mixed and dependent on numerous factors that vary between trials. Optimization of DCVs is essential; the selection of GBM-specific antigens and the utilization of 18F-fludeoxyglucose Positron Emission Tomography (FDG-PET) may add significant value and ultimately improve outcomes for patients undergoing treatment for glioblastoma. This review provides an overview of the mechanism of DCV, assesses previous clinical trials, and discusses future strategies for the integration of DCV into glioblastoma treatment protocols. To conclude, the review discusses challenges associated with the use of DCVs and highlights the potential of integrating DCV with standard therapies.

Small molecule inhibitors for cancer immunotherapy and associated biomarkers - the current status

Following the success of cancer immunotherapy using large molecules against immune checkpoint inhibitors, the concept of using small molecules to interfere with intracellular negative regulators of anti-tumor immune responses has emerged in recent years. The main targets for small molecule drugs currently include enzymes of negative feedback loops in signaling pathways of immune cells and proteins that promote immunosuppressive signals within the tumor microenvironment. In the adaptive immune system, negative regulators of T cell receptor signaling (MAP4K1, DGKα/ζ, CBL-B, PTPN2, PTPN22, SHP1), co-receptor signaling (CBL-B) and cytokine signaling (PTPN2) have been preclinically validated as promising targets and initial clinical trials with small molecule inhibitors are underway. To enhance innate anti-tumor immune responses, inhibitory immunomodulation of cGAS/STING has been in the focus, and inhibitors of ENPP1 and TREX1 have reached the clinic. In addition, immunosuppressive signals via adenosine can be counteracted by CD39 and CD73 inhibition, while suppression via intratumoral immunosuppressive prostaglandin E can be targeted by EP2/EP4 antagonists. Here, we present the status of the most promising small molecule drug candidates for cancer immunotherapy, all residing relatively early in development, and the potential of relevant biomarkers.

Estimating nitric oxide (NO) from MDSCs by Griess method

The functional importance of nitric oxide (NO) in the fields of immunology concerning its antimicrobial, anti-tumoral, anti-inflammatory, and immunosuppressive effects have made it inevitable to study its secretion from various cells. Nitrogen oxide synthase (NOS) is the enzyme responsible for synthesizing NO and its three isoforms function in a cell-dependent manner. NO is oxidized rapidly to Reactive nitrogen oxide species (RNOS) through which the roles of NO are being carried out. One of the major immune cells secreting NO is myeloid-derived suppressor cells (MDSCs). The function of these MDSCs in the suppression of T-cell proliferation as well as T-cell differentiation is found to be dependent on NO secretion. Apart from T-cell suppressive activity, NO is also known to interfere with natural killer (NK) cell functions. A convenient method to estimate NO secretion is by using Griess reagent named after Johann Peter Griess. In this method, NO reacts with the reagents to form a colored azo dye detectable using a microplate reader at a wavelength of 548nm. In this chapter, we summarized the detailed method of estimating NO from MDSCs by the Griess method.

The role of immunosuppressive myofibroblasts in the aging process and age-related diseases

Tissue-resident fibroblasts are mesenchymal cells which control the structural integrity of the extracellular matrix (ECM). Fibroblasts possess a remarkable plasticity to allow them to adapt to the changes in the microenvironment and thus maintain tissue homeostasis. Several stresses, also those associated with the aging process, convert quiescent fibroblasts into myofibroblasts which not only display fibrogenic properties but also act as immune regulators cooperating both with tissue-resident immune cells and those immune cells recruited into affected tissues. TGF-β cytokine and reactive oxygen species (ROS) are major inducers of myofibroblast differentiation in pathological conditions either from quiescent fibroblasts or via transdifferentiation from certain other cell types, e.g., macrophages, adipocytes, pericytes, and endothelial cells. Intriguingly, TGF-β and ROS are also important signaling mediators between immunosuppressive cells, such as MDSCs, Tregs, and M2 macrophages. It seems that in pathological states, myofibroblasts are able to interact with the immunosuppressive network. There is clear evidence that a low-grade chronic inflammatory state in aging tissues is counteracted by activation of compensatory immunosuppression. Interestingly, common enhancers of the aging process, such as oxidative stress, loss of DNA integrity, and inflammatory insults, are inducers of myofibroblasts, whereas anti-aging treatments with metformin and rapamycin suppress the differentiation of myofibroblasts and thus prevent age-related tissue fibrosis. I will examine the reciprocal interactions between myofibroblasts and immunosuppressive cells within aging tissues. It seems that the differentiation of myofibroblasts with age-related harmful stresses enhances the activity of the immunosuppressive network which promotes tissue fibrosis and degeneration in elderly individuals.

Thyroid transcription factor-1 (TTF-1) expression and the efficacy of combination therapy with immune checkpoint inhibitors and cytotoxic chemotherapy in non-squamous non-small cell lung cancer

Background

Thyroid transcription factor-1 (TTF-1) is expressed in approximately 70% of lung adenocarcinomas and is one of the most reliable makers to distinguish primary lung adenocarcinoma from metastatic disease. TTF-1-negative status is a poor prognostic factor, and TTF-1-negative lung adenocarcinoma is associated with poor efficacy of immune checkpoint inhibitor (ICI) monotherapy. However, the relationship between TTF-1 expression and the efficacy of ICI plus chemotherapy is still unclear.

Methods

We performed a retrospective analysis of 129 consecutive patients with advanced non-squamous non-small cell lung cancer (NS-NSCLC) treated with ICI monotherapy or ICI plus chemotherapy between January 2016 and December 2021. The expression of programmed death ligand-1 (PD-L1) and TTF-1 was also determined in cases for which no previous data were available. We then evaluated the association between TTF-1 expression status and treatment efficacy.

Results

Of the 129 cases, 33 were TTF-1-negative and 96 were positive. In the ICI monotherapy group (N=70), progression-free survival (PFS) was not significantly different between TTF-1-positive and negative patients (median 3.6 vs. 3.8 months, P=0.27); however, in patients with wild-type epidermal growth factor receptor (EGFR) and anaplastic lymphoma kinase (ALK), a trend for worse PFS was observed in TTF-1-negative cases compared with those that were TTF-1-positive (median 3.8 vs. 4.5 months, P=0.088). Moreover, long-term efficacy of ICI monotherapy (>2 years) was not observed in the TTF-1-negative group. TTF-1-negative patients tended to have worse overall survival (OS) than TTF-1-positive patients (median 15.6 vs. 19.5 months, P=0.13). In the ICI plus chemotherapy group (N=59), TTF-1-negative patients tended to have better PFS and similar OS compared with TTF-1-positive patients (median 9.9 vs. 9.6 months, P=0.14; median 32.3 vs. 18.9 months, P=0.78). Long-term efficacy was generally observed in TTF-1-negative patients treated with atezolizumab plus bevacizumab plus carboplatin plus paclitaxel (ABCP) (median PFS 22.5 months, median OS not reached).

Conclusions

ICI monotherapy is generally less efficacious in TTF-1-negative NS-NSCLC patients, and clinicians should consider ICI plus chemotherapy in these cases. Our study suggests that ABCP is an optimal regimen for TTF-1-negative NS-NSCLC.

Association between AHR Expression and Immune Dysregulation in Pancreatic Ductal Adenocarcinoma: Insights from Comprehensive Immune Profiling of Peripheral Blood Mononuclear Cells

Pancreatic cancer, particularly pancreatic ductal adenocarcinoma (PDAC), has an immune suppressive environment that allows tumour cells to evade the immune system. The aryl-hydrocarbon receptor (AHR) is a transcription factor that can be activated by certain exo/endo ligands, including kynurenine (KYN) and other tryptophan metabolites. Once activated, AHR regulates the expression of various genes involved in immune responses and inflammation. Previous studies have shown that AHR activation in PDAC can have both pro-tumorigenic and anti-tumorigenic effects, depending on the context. It can promote tumour growth and immune evasion by suppressing anti-tumour immune responses or induce anti-tumour effects by enhancing immune cell function. In this study involving 30 PDAC patients and 30 healthy individuals, peripheral blood samples were analysed. PDAC patients were categorized into Low (12 patients) and High/Medium (18 patients) AHR groups based on gene expression in peripheral blood mononuclear cells (PBMCs). The Low AHR group showed distinct immune characteristics, including increased levels of immune-suppressive proteins such as PDL1, as well as alterations in lymphocyte and monocyte subtypes. Functional assays demonstrated changes in phagocytosis, nitric oxide production, and the expression of cytokines IL-1, IL-6, and IL-10. These findings indicate that AHR's expression level has a crucial role in immune dysregulation in PDAC and could be a potential target for early diagnostics and personalised therapeutics.

Nivolumab after Induction Chemotherapy in Previously Treated Non-Small-Cell Lung Cancer Patients with Low PD-L1 Expression

This study aimed to investigate whether cyclophosphamide (C) and adriamycin (A) induction therapy (IT) prior to nivolumab could enhance the efficacy of nivolumab in previously treated patients with non-squamous (NSQ) non-small-cell lung cancer (NSCLC) with less than 10% programmed death-ligand 1 (PD-L1) expression. Twenty-two enrolled patients received four cycles of CA-IT every 3 weeks. Nivolumab was given 360 mg every 3 weeks from the second cycle and 480 mg every 4 weeks after four cycles of CA-IT. The median progression-free survival (PFS) and overall survival (OS) were 2.4 months and 11.6 months, respectively. Fluorescence-activated cell sorting revealed the lowest ratio of myeloid-derived suppressor cells (MDSCs) to CD8+T-cells in the responders. Proteomic analysis identified a consistent upregulation of extracellular matrix-receptor interactions and phagosome pathways in the responders. Among the differentially expressed proteins, the transferrin receptor protein (TFRC) was higher in the responders before treatment (fold change > 1.2). TFRC validation with an independent cohort showed the prognostic significance of either OS or PFS in patients with low PD-L1 expression. In summary, CA-IT did not improve nivolumab efficacy in NSQ-NSCLCs with low PD-L1 expression; however, it induced decreasing MDSC, resulting in a durable response. Higher baseline TFRC levels predicted a favorable response to nivolumab in NSCLC with low PD-L1 expression.

Hypoxia effects on oncolytic virotherapy in Cancer: Friend or Foe?

Researchers have tried to find novel strategies for cancer treatment in the past decades. Among the utilized methods, administering oncolytic viruses (OVs) alone or combined with other anticancer therapeutic approaches has had promising outcomes, especially in solid tumors. Infecting the tumor cells by these viruses can lead to direct lysis or induction of immune responses. However, the immunosuppressive tumor microenvironment (TME) is considered a significant challenge for oncolytic virotherapy in treating cancer. Based on OV type, hypoxic conditions in the TME can accelerate or repress virus replication. Therefore, genetic manipulation of OVs or other molecular modifications to reduce hypoxia can induce antitumor responses. Moreover, using OVs with tumor lysis capability in the hypoxic TME may be an attractive strategy to overcome the limitations of the therapy. This review summarizes the latest information available in the field of cancer virotherapy and discusses the dual effect of hypoxia on different types of OVs to optimize available related therapeutic methods.

Development and validation a prognostic model based on natural killer T cells marker genes for predicting prognosis and characterizing immune status in glioblastoma through integrated analysis of single-cell and bulk RNA sequencing

BACKGROUND

Glioblastoma (GBM) is an aggressive and unstoppable malignancy. Natural killer T (NKT) cells, characterized by specific markers, play pivotal roles in many tumor-associated pathophysiological processes. Therefore, investigating the functions and complex interactions of NKT cells is great interest for exploring GBM.

METHODS

We acquired a single-cell RNA-sequencing (scRNA-seq) dataset of GBM from Gene Expression Omnibus (GEO) database. The weighted correlation network analysis (WGCNA) was employed to further screen genes subpopulations. Subsequently, we integrated the GBM cohorts from The Cancer Genome Atlas (TCGA) and Chinese Glioma Genome Atlas (CGGA) databases to describe different subtypes by consensus clustering and developed a prognostic model by least absolute selection and shrinkage operator (LASSO) and multivariate Cox regression analysis. We further investigated differences in survival rates and clinical characteristics among different risk groups. Furthermore, a nomogram was developed by combining riskscore with the clinical characteristics. We investigated the abundance of immune cells in the tumor microenvironment (TME) by CIBERSORT and single sample gene set enrichment analysis (ssGSEA) algorithms. Immunotherapy efficacy assessment was done with the assistance of Tumor Immune Dysfunction and Exclusion (TIDE) and The Cancer Immunome Atlas (TCIA) databases. Real-time quantitative polymerase chain reaction (RT-qPCR) experiments and immunohistochemical profiles of tissues were utilized to validate model genes.

RESULTS

We identified 945 NKT cells marker genes from scRNA-seq data. Through further screening, 107 genes were accurately identified, of which 15 were significantly correlated with prognosis. We distinguished GBM samples into two distinct subtypes and successfully developed a robust prognostic prediction model. Survival analysis indicated that high expression of NKT cell marker genes was significantly associated with poor prognosis in GBM patients. Riskscore can be used as an independent prognostic factor. The nomogram was demonstrated remarkable utility in aiding clinical decision making. Tumor immune microenvironment analysis revealed significant differences of immune infiltration characteristics between different risk groups. In addition, the expression levels of immune checkpoint-associated genes were consistently elevated in the high-risk group, suggesting more prominent immune escape but also a stronger response to immune checkpoint inhibitors.

CONCLUSIONS

By integrating scRNA-seq and bulk RNA-seq data analysis, we successfully developed a prognostic prediction model that incorporates two pivotal NKT cells marker genes, namely, CD44 and TNFSF14. This model has exhibited outstanding performance in assessing the prognosis of GBM patients. Furthermore, we conducted a preliminary investigation into the immune microenvironment across various risk groups that contributes to uncover promising immunotherapeutic targets specific to GBM.

From Chaos to Opportunity: Decoding Cancer Heterogeneity for Enhanced Treatment Strategies

Cancer manifests as a multifaceted disease, characterized by aberrant cellular proliferation, survival, migration, and invasion. Tumors exhibit variances across diverse dimensions, encompassing genetic, epigenetic, and transcriptional realms. This heterogeneity poses significant challenges in prognosis and treatment, affording tumors advantages through an increased propensity to accumulate mutations linked to immune system evasion and drug resistance. In this review, we offer insights into tumor heterogeneity as a crucial characteristic of cancer, exploring the difficulties associated with measuring and quantifying such heterogeneity from clinical and biological perspectives. By emphasizing the critical nature of understanding tumor heterogeneity, this work contributes to raising awareness about the importance of developing effective cancer therapies that target this distinct and elusive trait of cancer.

Dendritic Cell Vaccines: A Shift from Conventional Approach to New Generations

In the emerging era of cancer immunotherapy, immune checkpoint blockades (ICBs) and adoptive cell transfer therapies (ACTs) have gained significant attention. However, their therapeutic efficacies are limited due to the presence of cold type tumors, immunosuppressive tumor microenvironment, and immune-related side effects. On the other hand, dendritic cell (DC)-based vaccines have been suggested as a new cancer immunotherapy regimen that can address the limitations encountered by ICBs and ACTs. Despite the success of the first generation of DC-based vaccines, represented by the first FDA-approved DC-based therapeutic cancer vaccine Provenge, several challenges remain unsolved. Therefore, new DC vaccine strategies have been actively investigated. This review addresses the limitations of the currently most adopted classical DC vaccine and evaluates new generations of DC vaccines in detail, including biomaterial-based, immunogenic cell death-inducing, mRNA-pulsed, DC small extracellular vesicle (sEV)-based, and tumor sEV-based DC vaccines. These innovative DC vaccines are envisioned to provide a significant breakthrough in cancer immunotherapy landscape and are expected to be supported by further preclinical and clinical studies.

Chimeric Peptide Engineered Bioregulator for Metastatic Tumor Immunotherapy through Macrophage Polarization and Phagocytosis Restoration

Tumor-associated macrophages (TAMs) are the most abundant immune cells in solid tumor tissues, which restrict antitumor immunity by releasing tumor-supporting cytokines and attenuating phagocytosis behaviors. In this work, a chimeric peptide engineered bioregulator (ChiP-RS) is constructed for tumor immunotherapy through macrophage polarization and phagocytosis restoration. ChiP-RS is fabricated by utilizing macrophage-targeting chimeric peptide (ChiP) to load Toll-like receptor agonists (R848) and Src homology 2 (SH2) domain-containing protein tyrosine phosphatase 2 (SHP-2) inhibitor (SHP099). Among which, ChiP-RS prefers to be internalized by TAMs, repolarizing M2 macrophages into M1 macrophages to reverse the immunosuppressive microenvironment. In addition, SHP-2 can be downregulated to promote phagocytotic elimination behaviors of M1 macrophages, which will also activate T cell-based antitumor immunity for metastatic tumor therapy. In vitro and in vivo findings demonstrate a superior suppression effect of ChiP-RS against metastatic tumors without systemic side effects. Such a simple but effective nanoplatform provides sophisticated synergism for immunotherapy, which may facilitate the development of translational nanomedicine for metastatic tumor treatment.

Nanozyme: a rising star for cancer therapy

In recent years, nanozymes have attracted enormous attention due to their effectiveness in promoting various catalytic reactions. To date, thousands of nanozymes have been discovered, including oxidase-like nanozymes, peroxidase-like nanozymes, and catalase-like nanozymes, covering noble metal, transition metal, and carbon nanomaterials. These nanozymes have been widely applied in various fields, including environmental protection, biosensing and nanomedicine. There are many reviews about this rising star being used in analytical chemistry. However, few works about nanozymes were related to cancer therapy. In this study, we comprehensively summarize the latest research advances on the strategies for cancer therapy based on different nanozymes. With traditional cancer treatment (including chemotherapy, radiotherapy, phototherapy), nanozyme catalytic therapy exhibited a synergistic effect for limiting the growth of tumors. Opportunities and trends for nanozymes in future cancer therapy are also discussed.

Single-cell profiling reveals the trajectory of FOLR2-expressing tumor-associated macrophages to regulatory T cells in the progression of lung adenocarcinoma

An immunosuppressive microenvironment enriched with regulatory CD4+ T lymphocytes (Tregs) facilitates the progression of lung adenocarcinoma (LUAD). This study aims to investigate the cellular mechanism underlying the formation of the immunosuppressive microenvironment in LUAD. LUAD samples (n = 12) and normal lung samples (n = 3) were obtained from patients with different pathological stages of LUAD. Single-cell RNA sequencing was performed to classify cellular components and analyze the transcriptomes, including transcription factors/targets and chemokine ligands/receptors, followed by bioinformatics study such as pseudotime analysis. Myeloid cells and T cells were the most abundant cell types in tumors and normal lung tissues, while tumor-associated macrophage-folate receptor 2 (TAM-FOLR2) and CD4+ nuclear receptor subfamily 4 group A member 3 (NR4A3) exhibited sharp increases in invasive adenocarcinoma (IA). The enrichment of TAM-FOLR2 in IA might result from alveolar resident macrophage-resistin (ARM-RETN) transformation and recruitment of dendritic cells (DCs) and other TAMs, as evidenced by temporal trajectories and differential expression profiles of chemokine ligands/receptors versus those in the early stages of tumors. High expression of CCL17/19/22 was observed in IA as well as in DCs, along with the strong interaction of TAM-FOLR2 with DCs. The results of pseudotime analysis suggested that CD4+NR4A3 might potentially convert to CD4+FOXP3, further supported by the high expression of NR4A3 target genes in CD4+FOXP3 cells. This study provides a single-cell transcriptome atlas from preinvasive to invasive LUAD and reveals a potential ARM-RETN/TAM-FOLR2/DCs/CD4+NR4A3/CD4+FOXP3 trajectory in shaping the immune suppressive microenvironment along the pathogenesis of LUAD.

Could the Crosstalk Between Myeloid-Derived-Suppressor Cells and Regulatory T Cells Have a Role in Beta-Thalassemia?

Background

Secondary iron overload, alloimmunization, and increased risk of infection are common complications in patients with transfusion-dependent thalassemia (TDT). Regulatory T cells (Tregs) and myeloid-derived suppressor cells (MDSCs) play an essential role in preventing excessive immune response. This research aimed to study the interaction between Tregs and MDSCs in TDT patients and to evaluate the association of these cell types with disease severity.

Methods

This case-control study included 26 patients with TDT and 23 healthy, age- and sex-matched controls. All patients were investigated for complete blood count (CBC), serum ferritin, and flow cytometric analysis of peripheral blood to detect Tregs, MDSCs, and MDSC subsets.

Results

A significant increase was observed in the frequencies of Tregs and MDSCs, particularly monocytic MDSCs (MO-MDSCs), in TDT patients compared with controls. The frequencies of these cells showed a direct association with ferritin level and total leukocyte count and an inverse association with hemoglobin level. Furthermore, a positive correlation was observed between Tregs and each of the total MDSCs and MO-MDSCs.

Conclusions

Levels of Tregs and MDSCs increased in TDT and may probably have a role in suppressing the active immune systems of TDT patients.

Radiation combined with ultrasound and microbubbles: A potential novel strategy for cancer treatment

Cancer is one of the leading causes of death worldwide. Several emerging technologies are helping to battle cancer. Cancer therapies have been effective at killing cancer cells, but a large portion of patients still die to this disease every year. As such, more aggressive treatments of primary cancers are employed and have been shown to be capable of saving a greater number of lives. Recent research advances the field of cancer therapy by employing the use of physical methods to alter tumor biology. It uses microbubbles to enhance radiation effect by damaging tumor vasculature followed by tumor cell death. The technique can specifically target tumor volumes by conforming ultrasound fields capable of microbubbles stimulation and localizing it to avoid vascular damage in surrounding tissues. Thus, this new application of ultrasound-stimulated microbubbles (USMB) can be utilized as a novel approach to cancer therapy by inducing vascular disruption resulting in tumor cell death. Using USMB alongside radiation has showed to augment the anti-vascular effect of radiation, resulting in enhanced tumor response. Recent work with nanobubbles has shown vascular permeation into intracellular space, extending the use of this new treatment method to potentially further improve the therapeutic effect of the ultrasound-based therapy. The significant enhancement of localized tumor cell kill means that radiation-based treatments can be made more potent with lower doses of radiation. This technique can manifest a greater impact on radiation oncology practice by increasing treatment effectiveness significantly while reducing normal tissue toxicity. This review article summarizes the past and recent advances in USMB enhancement of radiation treatments. The review mainly focuses on preclinical findings but also highlights some clinical findings that use USMB as a therapeutic modality in cancer therapy.

Clinical Trials of Cellular Therapies in Solid Tumors

In the past years cancer treatments have drastically changed, mainly due to the development of immune checkpoint inhibitors capable of immune modulation in vivo, thus providing major clinical benefit in a number of malignancies. Simultaneously, considerable technical refinements have opened new prospects for the development of immune cell-based medicinal products and unprecedented success with chimeric antigen receptor (CAR)-T cells targeting B-cell hematologic malignancies has been obtained. However, T cell therapies introduced and performed in the field of solid tumors have produced so far only limited responses in selected patient populations. This standstill is attributable to the difficulty in identifying target antigens which are homogeneously expressed by all tumor cells while absent from normal tissues, and the limited T cell persistence and proliferation in a hostile tumor microenvironment that favors immune escape. Replicating the results observed in hematology is a major scientific challenge in solid tumors, and ongoing translational and clinical research is focused on obtaining insight into the mechanisms of tumor recognition and evasion, and how to improve the efficacy of cellular therapies, also combining them with immune checkpoint inhibitors or other agents targeting either the cancer cell or the tumor environment. This paper provides an overview of current adaptive T cell therapy approaches in solid tumors, the research performed to increase their efficacy and safety, and results from ongoing clinical trials.

Nanoengineered drug delivery in cancer immunotherapy for overcoming immunosuppressive tumor microenvironment

Almost like a living being in and of itself, tumors actively interact with and modify their environment to escape immune responses. Owing to the pre-formation of cancer-favorable microenvironment prior to anti-cancer treatment, the numerous attempts that followed propose limited efficacy in oncology. Immunogenicity by activation of immune cells within the tumor microenvironment or recruitment of immune cells from nearby lymph nodes is quickly offset as the immunosuppressive environment, rapidly converting immunogenic cells into immune suppressive cells, overriding the immune system. Tumor cells, as well as regulatory cells, namely M2 macrophages, Treg cells, and MDSCs, derived by the immunosuppressive environment, also cloak from potential anti-tumoral factors by directly or indirectly secreting cytokines, such as IL-10 and TGF-β, related to immune regulation. Enzymes and other metabolic or angiogenetic constituents - VEGF, IDO1, and iNOS - are also employed directed for anti-cancer immune cell malfunctioning. Therefore, the conversion of "cold" immunosuppressive environment into "hot" immune responsive environment is of paramount importance, bestowing the advances in the field of cancer immunotherapy the opportunity to wholly fulfill its intended purpose. This paper reviews the mechanisms by which tumors wield to exercise immune suppression and the nanoengineered delivery strategies being developed to overcome this suppression.

Peptide-Based Vaccine against Breast Cancer: Recent Advances and Prospects

Breast cancer is considered the second-leading cancer after lung cancer and is the most prevalent cancer among women globally. Currently, cancer immunotherapy via vaccine has gained great attention due to specific and targeted immune cell activity that creates a potent immune response, thus providing long-lasting protection against the disease. Despite peptides being very susceptible to enzymatic degradation and poor immunogenicity, they can be easily customized with selected epitopes to induce a specific immune response and particulate with carriers to improve their delivery and thus overcome their weaknesses. With advances in nanotechnology, the peptide-based vaccine could incorporate other components, thereby modulating the immune system response against breast cancer. Considering that peptide-based vaccines seem to show remarkably promising outcomes against cancer, this review focuses on and provides a specific view of peptide-based vaccines used against breast cancer. Here, we discuss the benefits associated with a peptide-based vaccine, which can be a mainstay in the prevention and recurrence of breast cancer. Additionally, we also report the results of recent trials as well as plausible prospects for nanotechnology against breast cancer.