Combination of DC/CIK adoptive T cell immunotherapy with chemotherapy in advanced non-small-cell lung cancer (NSCLC) patients: a prospective patients’ preference-based study (PPPS)

Combined oral low-dose cyclophosphamide endocrine therapy may improve clinical response among patients with metastatic breast cancer via Tregs in TLSs

Despite limited research on refractory and/or endocrine therapy failure in elderly metastatic breast cancer (MBC) patients, a prior study showed that low-dose oral cyclophosphamide (CY) can improve the overall survival rate of MBC patients, possibly through the immunoregulation of regulatory T cells (Tregs). We preliminarily investigated the combination of endocrine therapy (ET) with oral low-dose CY as salvage therapy in elderly patients via peripheral blood regulatory T-cell analyses. In addition, we evaluated the associations of tumor tertiary lymphoid structures (TLSs) with therapeutic outcomes. HR+/HER2- advanced breast cancer patients who received low-dose CY combined with ET or ET only from April 2015 to August 2021 were enrolled in this retrospective study. The primary outcome was the clinical control rate (CCR), and the secondary outcome was progression-free survival (PFS). Circulating T lymphocyte subpopulations represented by Tregs were monitored during treatment by flow cytometry methods. TLSs wereconfirmed by hematoxylin-eosin staining of pretreatment specimens, and CD3, CD4, and Foxp3 were detected using Opal multicolor immunofluorescence. A total of 85 patients who received CY + ET and 50 patients who received ET only were enrolled, the percentage of patients who received CCR was 73% (62/85) vs. 70% (45/50), and the objective response rate (ORR) was 28% (24/85) vs. 24% (12/50). No deaths occurred during the study period. The mean PFS time was 13 vs. 11 months (P = 0.03). In the CY + ET group, decreases in CD4+/CD25+/Foxp3+ T cells (P < 0.001) were favorable for both clinical control and prolonged PFS (P < 0.001). Compared with patients without TLSs, those with TLSs were more likely to have better clinical control and PFS (mean time = 6 months), and a greater number of Treg cells during TLS pretreatment correlated with longer PFS (P = 0.043). Oral low-dose CY combined with standard ET exerts immunological effects by decreasing Treg levels to achieve improved clinical responses. Moreover, patients with TLSs might benefit more from such therapy than those without TLSs, and a high Treg cell count in TLSs before treatment predicts better therapeutic efficacy.

Neoantigen Identification and Dendritic Cell-Based Vaccines for Lung Cancer Immunotherapy

Immunotherapies can treat many cancers, including difficult-to-treat cases such as lung cancer. Due to its tolerability, long-lasting therapeutic responses, and efficacy in a wide spectrum of patients, immunotherapy can also help to treat lung cancer, which has few treatment choices. Tumor-specific antigens (TSAs) for cancer vaccinations and T-cell therapies are difficult to discover. Neoantigens (NeoAgs) from genetic mutations, irregular RNA splicing, protein changes, or viral genetic sequences in tumor cells provide a solution. NeoAgs, unlike TSAs, are non-self and can cause an immunological response. Next-generation sequencing (NGS) and bioinformatics can swiftly detect and forecast tumor-specific NeoAgs. Highly immunogenic NeoAgs provide personalized or generalized cancer immunotherapies. Dendritic cells (DCs), which originate and regulate T-cell responses, are widely studied potential immunotherapeutic therapies for lung cancer and other cancers. DC vaccines are stable, reliable, and safe in clinical trials. The purpose of this article is to evaluate the current status, limitations, and prospective clinical applications of DC vaccines, as well as the identification and selection of major histocompatibility complex (MHC) class I and II genes for NeoAgs. Our goal is to explain DC biology and activate DC manipulation to help researchers create extremely potent cancer vaccines for patients.

The Therapeutic Potential of Cytokine-Induced Killer in Patients with Cancer

Despite the promising results of immunotherapy, further experiments need to be considered because of several factors ranging from physical barriers to off-tumor adverse effects. It is surprising that adoptive cellular immunotherapy, particularly dendritic cell and cytokine-induced killer (DC-CIK) therapy, is far less emphasized in the treatment of cancer diseases. DC-CIK therapy in cancer patients presents auspicious results with low or no side effects, which should not be overlooked. More interestingly, almost all DC-CIK clinical trials are ongoing in China that highlight the limitations of therapeutic strategies and require large-scale research. To date, it is advisable to consider combination therapy with chemotherapy since it has shown promising outcomes with higher efficacy. In this article, the efficacy of DC-CIK therapy in patients with cancer is summarized by underscoring the lack of experiments on soft cancers on an unprecedented scale. In brief, DC-CIK therapy is a safe and effective therapeutic agent for malignant and nonmalignant diseases that enhances short-term and long-term effects.

Peripheral Blood CD8+ CD28+ T Cells as an Independent Predictor of Treatment Response and Survival After Concurrent Chemoradiotherapy in Pediatric High-Grade Glioma Patients

Backgroud

The tumor immune microenvironment influences the efficiency of concurrent chemoradiotherapy (CCRT) in high-grade glioma (HGG). This study investigated peripheral blood T lymphocyte subsets as clinical indicators of therapeutic response and prognosis in pediatric high-grade glioma (pHGG).

Methods

This retrospective study included 77 patients with postoperative pHGG who were treated concurrently with temozolomide and external beam radiotherapy between January 1, 2012, and December 31, 2018. The median follow-up was 26 (range: 5-106) months. Peripheral venous blood samples were collected before and after CCRT. The proportions of peripheral blood T lymphocytes and their association with treatment outcome and survival were determined.

Results

Sixty-four (83.1%) patients achieved complete remission, partial remission, and stable disease, and 13 (16.9%) patients had progressive disease. Higher CD3+ T cell, CD4+ T cell, and CD8+ CD28+ T cell ratios were predictive of better response, while a higher CD8+ CD28- T cell ratio was predictive of poorer response. Binary logistic regression analysis showed that the CD8+ CD28+ T cell ratio was a significant independent predictor of CCRT response (odds ratio [OR] = 53.521, 95% confidence interval [CI] = 4.294-667.119, P = .002). Univariate and multivariate analysis of prognostic factors associated with survival showed that the CD8+ CD28+ T lymphocyte ratio was a significant independent predictor of progression-free survival (hazard ratio [HR] = 1.80, 95% CI = 1.06-3.08, P = .03), but none of the subsets were significantly associated with overall survival.

Conclusion

Peripheral blood T lymphocytes have potential as predictors of CCRT response and prognosis in pHGG.

Current immune therapeutic strategies in advanced or metastatic non-small cell lung cancer

ABSTRACT

Immune escape mechanisms in non-small cell lung cancer (NSCLC) can disrupt every step of the anti-cancer immune response. In recent years, an increased understanding of the specific mechanisms fueling immune escape has allowed for the development of numerous immunotherapeutic treatments that have been introduced into the clinical practice. The advent of immunotherapy has dramatically changed the current treatment landscape of advanced or metastatic NSCLC because of its durable efficacy and manageable toxicity. In this review, we will first present a brief overview of recent evidence on immune escape mechanisms in NSCLC. We will then discuss the current promising immunotherapeutic strategies in advanced or metastatic NSCLC tumors.

Therapies Targeting Immune Cells in Tumor Microenvironment for Non-Small Cell Lung Cancer

The tumor microenvironment (TME) plays critical roles in immune modulation and tumor malignancies in the process of cancer development. Immune cells constitute a significant component of the TME and influence the migration and metastasis of tumor cells. Recently, a number of therapeutic approaches targeting immune cells have proven promising and have already been used to treat different types of cancer. In particular, PD-1 and PD-L1 inhibitors have been used in the first-line setting in non-small cell lung cancer (NSCLC) with PD-L1 expression ≥1%, as approved by the FDA. In this review, we provide an introduction to the immune cells in the TME and their efficacies, and then we discuss current immunotherapies in NSCLC and scientific research progress in this field.

Adjuvant cytokine-induced killer cell immunotherapy improves long-term survival in patients with stage I-II non-small cell lung cancer after curative surgery

BACKGROUND AIMS

Non-small cell lung cancer (NSCLC) remains the most common cancer worldwide, with an annual incidence of around 1.3 million. Surgery represents the standard treatment in early-stage NSCLC when feasible. However, because of cancer recurrence, only approximately 53% of patients with stage I and II NSCLC survive 5 years after radical surgery. The authors performed a retrospective study to investigate the impact of cytokine-induced killer (CIK) cell immunotherapy on the long-term survival of patients with stage I-II NSCLC after curative resection.

METHODS

Fifty-seven patients with NSCLC were included in the study, with 41 and 16 in the control and CIK groups, respectively. Clinical characteristics were compared using a t-test and χ² test. Survival analysis of patients with NSCLC was performed using the Kaplan-Meier method. The phenotypes and anti-tumor functions of CIK cells were evaluated by flow cytometry.

RESULTS

Patients in the CIK group exhibited significantly longer overall survival (OS) and better disease-free survival (DFS) than those in the control group. Subgroup analysis indicated that patients with a higher risk of recurrence benefited more from CIK treatment and attained longer OS and DFS compared with those in the control group. No severe adverse events related to CIK treatment occurred. CIK cells contained a higher proportion of CD3⁺CD56⁺ natural killer (NK) T cells and CD3⁺ and CD8⁺ T cells and a lower proportion of CD3^-CD56⁺ NK cells compared with peripheral blood mononuclear cells. CIK cells exhibited potent tumor-killing ability, with longer contact times with tumor cells and a greater number of cells exposed to tumor cells.

CONCLUSIONS

The authors' data suggest that adjuvant CIK cell therapy is a safe and effective therapeutic strategy for improving OS and DFS in patients with stage I-II NSCLC after curative resection.

Overexpression of lncRNA TUG1 enhances the efficacy of DC-CIK immunotherapy in neuroblastoma in vitro and in vivo

BACKGROUND

Long non-coding RNA (LncRNA) TUG1 plays a critical role in the development of human cancers. This study explored whether TUG1 is involved in the cytotoxicity of dendritic cells and cytokine-induced killer cells (DCs-CIK), an immunotherapy approach, in neuroblastoma.

METHODS

A TUG1 expression plasmid was transfected into DCs. Neuroblastoma SK-N-SH cells were incubated with CIK cells, DCs-CIK cells, and TUG1-overexpressing DCs-CIK cells, with or without irradiation. SK-N-SH cell viability, colony formation, migration, and apoptosis were analyzed using CCK-8, colony formation assay, transwell assay, and flow cytometry, respectively. Production of IL-12, IL-2 and IFN-γ in the supernatants was determined using ELISA. A dual luciferase activity assay was performed to confirm the molecular interactions between TUG1 and miR-204. Tumor-bearing mice were established by injection of SK-N-SH cells followed by stimulation with CIK cells, DC-CIK cells, and TUG1-overexpressing DCs-CIK cells.

RESULTS

Compared to CIK alone or DC-CIK therapy, overexpression of TUG1 significantly suppressed tumor cell proliferation, colony formation, and migration of neuroblastoma cells. Moreover, upregulation of TUG1 robustly induced apoptosis and altered key molecules associated with apoptosis and epithelial-mesenchymal transition. Contents of IL-12, IL-2 and IFN-γ were dramatically elevated in the supernatants in the coculturing system upon transfection with TUG1. In addition, TUG1 was found to be act as miR-204 sponge. Furthermore, in vivo experiments demonstrated that upregulation of TUG1 potentiated the antitumor activity of DC-CIK immunotherapy.

CONCLUSION

Overexpression of TUG1 promotes DC maturation and enhances CIK cytotoxicity, suggesting that TUG1 may be a novel target for enhancing DC-CIK based immunotherapy for neuroblastoma.

NK and cells with NK-like activities in cancer immunotherapy-clinical perspectives

Natural killer (NK) cells are lymphoid cells of innate immunity that take important roles in immune surveillance. NK cells are considered as a bridge between innate and adaptive immunity, and their infiltration into tumor area is related positively with prolonged patient survival. They are defined as CD16⁺ CD56⁺ CD3^- cells in clinic. NK cells promote cytolytic effects on target cells and induce their apoptosis. Loss of NK cell cytotoxic activity and reduction in the number of activating receptors are the current issues for application of such cells in cellular immunotherapy, which resulted in the diminished long-term effects. The focus of this review is to discuss about the activity of NK cells and cells with NK-like activity including natural killer T (NKT), cytokine-induced killer (CIK) and lymphokine-activated killer (LAK) cells in immunotherapy of human solid cancers.

DAP10 Predicted the Outcome of Pediatric B-Cell Acute Lymphoblastic Leukemia and Was Associated with the T-Cell Exhaustion

B-cell acute lymphoblastic leukemia is the most common malignant tumor in children. About 10–15% of patients will relapse with a 5-year OS of 57.5% for the past 20 years. As tumor microenvironment plays an important role in the disease process, many types of immunotherapy are approached. New immunotherapies including CAR-T cells have been developed for refractory B-ALL treatment. However, CAR-T treatment faces several problems, including loss of the target antigen and in vivo T-cell persistence. Here, we analyzed the tumor microenvironment of pediatric B-ALL patients in TARGET database. Using Cox analysis and PPI network, we finally sorted out the DAP10 gene. We found that DAP10 was hardly expressed in leukemic B cells. DAP10 was downregulated in B-ALL compared with normal individuals, and low expression level of DAP10 predicted poor survival. Furthermore, we found the tumor microenvironment was different in DAP10 high and low expression children. The CD8+ T cells might be hard to activate and more likely to suffer from exhaustion in DAP10 lowly expressed children. In conclusion, our results showed that DAP10 was a well biomarker to indicate the prognosis and tumor microenvironment in pediatric B-ALL. The treatment strategy of immunotherapy for the leukemic children with DAP10 lowly expressed should be adjusted if needed.

The spliceosome pathway activity correlates with reduced anti-tumor immunity and immunotherapy response, and unfavorable clinical outcomes in pan-cancer

Alterations in the spliceosome pathway (SP) have been associated with diverse human cancers. In this study, we explored associations of the SP activity with various clinical features, anti-tumor immune signatures, tumor immunity-related genomic and molecular features, and the response to immunotherapies and targeted therapies in 29 cancer types from The Cancer Genome Atlas (TCGA) database. We showed that the SP activity was an oncogenic signature, as evidenced by its hyperactivation in cancer and invasive cancer subtypes and correlations with unfavorable clinical outcomes and anti-tumor immunosuppression in various cancers. The SP activity showed positive correlations with tumor mutation burden (TMB) and aneuploidy in diverse cancers, suggesting its association with genomic instability. However, the negative association between the SP activity and anti-tumor immune response was independent of its associations with aneuploidy and TMB. Furthermore, we supported that the SP activity had a negative correlation with immunotherapy response in four cancer cohorts treated by immune checkpoint inhibitors. Moreover, elevated SP activity is correlated with increased drug sensitivity for a broad spectrum of anti-tumor targeted therapies. In conclusion, the SP activity is a negative biomarker for anti-tumor immune response, prognosis, and the response to immunotherapeutic and targeted drugs in pan-cancer.

Pan-cancer analysis reveals that neurotrophin signaling correlates positively with anti-tumor immunity, clinical outcomes, and response to targeted therapies and immunotherapies in cancer

AIMS

The crosstalk between cancer cells and nerves plays an important role in tumor biology. However, the correlation between the neurotrophin signaling (NS) and anti-tumor immunity and immunotherapy response in cancer remains unexplored.

MATERIALS AND METHODS

We analyzed associations of NS with anti-tumor immune signatures, tumor immunity-related molecular and genomic features, and clinical features in 33 TCGA cancer types. We also explored the association between NS and the response to immune checkpoint inhibitors (ICIs) in four cancer cohorts.

KEY FINDINGS

NS scores had significant positive correlations with the enrichment scores of anti-tumor immune signatures, including CD8+ T cells, interferon response, natural killer cells, Toll-like receptor and NOD-like receptor signaling pathways in most cancer types. NS scores were inversely correlated with the scores of DNA damage repair pathways, tumor mutation burden, copy number alterations, intra-tumor heterogeneity, and tumor stemness in diverse cancers. In contrast, NS scores were significantly and positively correlated with the apoptosis pathway's scores in 32 of the 33 cancer types. NS scores were significantly lower in early-stage versus late-stage and in primary versus metastatic tumors in diverse cancers. Higher NS scores were correlated with better survival in pan-cancer and in eight individual cancer types. Moreover, the response rate to ICIs was higher in higher-NS-score than in lower-NS-score tumors in four cancer cohorts. Elevated NS was correlated with increased drug sensitivity for numerous anti-tumor targeted drugs.

SIGNIFICANCE

NS is a positive biomarker for anti-tumor immune response, prognosis, and the response to targeted and immunotherapeutic drugs in cancer.

Interleukin-2 therapy of cancer-clinical perspectives

Interleukin (IL)-2 is a pleiotropic cytokine that displays opposing activities on immune system acting either in favor of or against cancer progression. Advanced/metastatic melanoma and renal cell carcinoma (RCC) are the two types of cancers that included most studies implemented for assessing the role of high-dose IL-2 therapy. The use of high-dose IL-2 therapy can, however, increase the rate of toxicities and interferes with the activity of endothelial cells (ECs) and effector T cells in tumor microenvironment (TME). This implies the need for adjusting strategies related to the cytokine therapy, such as suppressing signals that are interfering with the activity of this cytokine or the use of engineered IL-2 variants. The focus of this review is to discuss about pros and cons related to the IL-2 therapy and propose strategies to increase the efficacy of therapy. The outcomes of this literature will call for application of variants of IL-2 engineered to represent higher half-life and efficacy, and are more safe in the area of cancer immunotherapy.

Recent Advances and Future Perspective of DC-Based Therapy in NSCLC

Current treatment for patients with non-small-cell lung cancer (NSCLC) is suboptimal since therapy is only effective in a minority of patients and does not always induce a long-lasting response. This highlights the importance of exploring new treatment options. The clinical success of immunotherapy relies on the ability of the immune system to mount an adequate anti-tumor response. The activation of cytotoxic T cells, the effector immune cells responsible for tumor cell killing, is of paramount importance for the immunotherapy success. These cytotoxic T cells are primarily instructed by dendritic cells (DCs). DCs are the most potent antigen-presenting cells (APCs) and are capable of orchestrating a strong anti-cancer immune response. DC function is often suppressed in NSCLC. Therefore, resurrection of DC function is an interesting approach to enhance anti-cancer immune response. Recent data from DC-based treatment studies has given rise to the impression that DC-based treatment cannot induce clinical benefit in NSCLC by itself. However, these are all early-phase studies that were mainly designed to study safety and were not powered to study clinical benefit. The fact that these studies do show that DC-based therapies were well-tolerated and could induce the desired immune responses, indicates that DC-based therapy is still a promising option. Especially combination with other treatment modalities might enhance immunological response and clinical outcome. In this review, we will identify the possibilities from current DC-based treatment trials that could open up new venues to improve future treatment.

Changes in Peripheral Blood Regulatory T Cells and IL-6 and IL-10 Levels Predict Response of Pediatric Medulloblastoma and Germ Cell Tumors With Residual or Disseminated Disease to Craniospinal Irradiation

PURPOSE

Radiation therapy (RT) modulates immune cells and cytokines, resulting in both clinically beneficial and detrimental effects. The changes in peripheral blood T lymphocyte subsets and cytokines during RT for pediatric brain tumors and the association of these changes with therapeutic outcomes have not been well described.

METHODS AND MATERIALS

The study population consisted of children (n = 83, aged 3~18) with primary brain tumors (medulloblastoma, glioma, germ cell tumors (GCT), and central nervous system embryonal tumor-not otherwise specified), with or without residual or disseminated (R/D) diseases who were starting standard postoperative focal or craniospinal irradiation (CSI). Peripheral blood T lymphocyte subsets collected before and 4 weeks after RT were enumerated by flow cytometry. Plasma levels of interleukin (IL)-2, IL-4, IL-6, IL-10, tumor necrosis factor-α, interferon-γ, and IL-17A were measured by cytometric bead array.

RESULTS

Patients with R/D lesions receiving CSI (n = 32) had a post-RT increase in the frequency of CD3+T and CD8+T cells, a decrease in CD4+T cells, and an increase in regulatory T cells (Tregs) and CD8+CD28- suppressor cells, which was more predominantly seen in these patients than in other groups. In the CSI group with such R/D lesions, consisting of patients with medulloblastoma and germ cell tumors, 19 experienced a complete response (CR) and 13 experienced a partial response (PR) on imaging at 4 weeks after RT. The post/pre-RT ratio of Tregs (P = .0493), IL-6 (P = .0111), and IL-10 (P = .0070) was lower in the CR group than in the PR group. Multivariate analysis revealed that the post/pre-RT ratios of Treg, IL-6, and IL-10 were independent predictors of CR (P < .0001, P = .018, P < .0001, respectively). The areas under the receiver operating curves and confidence intervals were 0.7652 (0.5831-0.8964), 0.7794 (0.5980-0.9067), and 0.7085 (0.5223-0.8552) for IL-6, IL-10, and Treg, respectively. The sensitivities of IL-6, IL-10, and Treg to predict radiotherapeutic responses were 100%, 92.3%, and 61.5%, and specificity was 52.6%, 57.9%, and 84.2%, respectively.

CONCLUSIONS

CSI treatment to those with R/D lesions predominantly exerted an effect on antitumor immune response compared with both R/D lesion-free but exposed to focal or CSI RT and with R/D lesions and exposed to focal RT. Such CSI with R/D lesions group experiencing CR is more likely to have a decrease in immunoinhibitory molecules and cells than patients who only achieve PR. Measuring peripheral blood Treg, IL-6, and IL-10 levels could be valuable for predicting radiotherapeutic responses of pediatric brain tumors with R/D lesions to CSI for medulloblastoma and intracranial germ cell tumors.

Synthetic MUC1 breast cancer vaccine containing a Toll-like receptor 7 agonist exerts antitumor effects

Adjuvant immunotherapy has recently emerged as a potential treatment strategy for breast cancer. The tumor-associated protein mucin 1 (MUC1) has received increasing attention due to its high expression in numerous types of common tumors, in which MUC1 acts as a cancer antigen. However, the simple mixed composition of an adjuvant and a peptide is not a sufficient rationale for a MUC1 peptide-based vaccine. The present study developed a novel Toll-like receptor 7 (TLR7) agonist-conjugated MUC1 peptide vaccine (T7-MUC1), which elicited an effective immune response and a robust antitumor effect in a mouse breast cancer model. In vitro, T7-MUC1 significantly increased the release of cytokines in mouse bone marrow dendritic cells and spleen lymphocytes, and induced the dendritic cell-cytokine-induced killer response against tumor cells with high MUC1 expression. In vivo, it was observed that the 4T1 tumor weights in mice immunized with the T7-MUC1 conjugate were reduced by ≥70% compared with those in the control group. Furthermore, the therapeutic responses in vivo were attributed to the increase in specific humoral and cellular immunity, including high antibody titers, antibody-dependent cell-mediated cytotoxicity and cytotoxic T-lymphocyte activity. The percentages of CD3⁺/CD8⁺ T-cells were significantly higher in the T7-MUC1 treatment group compared with those in the control group. Therefore, the results of the present study suggested that the T7-MUC1 vaccine inhibited tumor growth in mice and thus may have potential as a therapeutic candidate in clinical trials for breast cancer immunotherapy.

Ten-year update of the international registry on cytokine-induced killer cells in cancer immunotherapy

Cytokine-induced killer (CIK) cells represent an exceptional T-cell population uniting a T cell and natural killer cell-like phenotype in their terminally differentiated CD3⁺ CD56⁺ subset, which features non-MHC-restricted tumor-killing activity. CIK cells have provided encouraging results in initial clinical studies and revealed synergistic antitumor effects when combined with standard therapeutic procedures. We established the international registry on CIK cells (IRCC) to collect and evaluate clinical trials for the treatment of cancer patients in 2010. Moreover, our registry set new standards on the reporting of results from clinical trials using CIK cells. In the present update, a total of 106 clinical trials including 10,225 patients were enrolled in IRCC, of which 4,889 patients in over 30 distinct tumor entities were treated with CIK cells alone or in combination with conventional or novel therapies. Significantly improved median progression-free survival and overall survival were shown in 27 trials, and 9 trials reported a significantly increased 5-year survival rate. Mild adverse effects and graft-versus-host diseases were also observed in the studies. Recently, more efforts have been put into the improvement of antitumoral efficacy by CIK cells including the administration of immune checkpoint inhibitors and modification with chimeric antigen receptorc. The minimal toxicity and multiple improvements on their tumor-killing activity both make CIK cells a favorable therapeutic tool in the clinical practice of cancer immunotherapy.

CARs: Beyond T Cells and T Cell-Derived Signaling Domains

When optimizing chimeric antigen receptor (CAR) therapy in terms of efficacy, safety, and broadening its application to new malignancies, there are two main clusters of topics to be addressed: the CAR design and the choice of transfected cells. The former focuses on the CAR construct itself. The utilized transmembrane and intracellular domains determine the signaling pathways induced by antigen binding and thereby the cell-specific effector functions triggered. The main part of this review summarizes our understanding of common signaling domains employed in CARs, their interactions among another, and their effects on different cell types. It will, moreover, highlight several less common extracellular and intracellular domains that might permit unique new opportunities. Different antibody-based extracellular antigen-binding domains have been pursued and optimized to strike a balance between specificity, affinity, and toxicity, but these have been reviewed elsewhere. The second cluster of topics is about the cellular vessels expressing the CAR. It is essential to understand the specific attributes of each cell type influencing anti-tumor efficacy, persistence, and safety, and how CAR cells crosstalk with each other and bystander cells. The first part of this review focuses on the progress achieved in adopting different leukocytes for CAR therapy.

Next-generation immuno-oncology agents: current momentum shifts in cancer immunotherapy

Cancer immunotherapy has reached a critical point, now that immune checkpoint inhibitors and two CAR-T products have received market approval in treating 16 types of cancers and 1 tissue-agnostic cancer indication. Accompanying these advances, the 2018 Nobel Prize was awarded for the discovery of immune checkpoint pathways, which has led to the revolution of anti-cancer treatments. However, expanding the indications of immuno-oncology agents and overcoming treatment resistance face mounting challenges. Although combination immunotherapy is an obvious strategy to pursue, the fact that there have been more failures than successes in this effort has served as a wake-up call, placing emphasis on the importance of building a solid scientific foundation for the development of next-generation immuno-oncology (IO) agents. The 2019 China Cancer Immunotherapy Workshop was held to discuss the current challenges and opportunities in IO. At this conference, emerging concepts and strategies for IO development were proposed, focusing squarely on correcting the immunological defects in the tumor microenvironment. New targets such as Siglec-15 and new directions including neoantigens, cancer vaccines, oncolytic viruses, and cytokines were reviewed. Emerging immunotherapies were discussed in the areas of overcoming primary and secondary resistance to existing immune checkpoint inhibitors, activating effector cells, and targeting immunosuppressive mechanisms in the tumor microenvironment. In this article, we highlight old and new waves of IO therapy development, and provide perspectives on the latest momentum shifts in cancer immunotherapy.

DC-CIK as a widely applicable cancer immunotherapy

Introduction: Immunotherapy is now a standard treatment for many malignancies. Although immune checkpoint inhibition has demonstrated substantial efficacy by enhancing T cell activation and function in the tumor microenvironment, adoptive transfer of T and NK cell products promises to provide activated cells capable of immediate and direct tumor destruction. A widely applicable, non-MHC dependent, cellular therapy, consisting of in vitro generated dendritic cells (DC) combined with cytokine-induced killer cells (CIK), is highly efficient to produce from individual patients and has demonstrated safety and efficacy alone or with chemotherapy.Areas covered: We summarize the clinical data from studies of DC-CIK and discuss future research directions.Expert opinion: Patients with a wide variety of tumor types who have received DC-CIK therapy may experience clinical responses. This versatile therapy synergizes with other anti-cancer therapies including chemotherapy and immunotherapy.

Therapeutic Cancer Vaccination with Ex Vivo RNA-Transfected Dendritic Cells-An Update

Over the last two decades, dendritic cell (DC) vaccination has been studied extensively as active immunotherapy in cancer treatment and has been proven safe in all clinical trials both with respect to short and long-term side effects. For antigen-loading of dendritic cells (DCs) one method is to introduce mRNA coding for the desired antigens. To target the whole antigenic repertoire of a tumor, even the total tumor mRNA of a macrodissected biopsy sample can be used. To date, reports have been published on a total of 781 patients suffering from different tumor entities and HIV-infection, who have been treated with DCs loaded with mRNA. The majority of those were melanoma patients, followed by HIV-infected patients, but leukemias, brain tumors, prostate cancer, renal cell carcinomas, pancreatic cancers and several others have also been treated. Next to antigen-loading, mRNA-electroporation allows a purposeful manipulation of the DCs’ phenotype and function to enhance their immunogenicity. In this review, we intend to give a comprehensive summary of what has been published regarding clinical testing of ex vivo generated mRNA-transfected DCs, with respect to safety and risk/benefit evaluations, choice of tumor antigens and RNA-source, and the design of better DCs for vaccination by transfection of mRNA-encoded functional proteins.

Predictive significance of T cell subset changes during ex vivo generation of adoptive cellular therapy products for the treatment of advanced non-small cell lung cancer

Adoptive T cell immunotherapy with cytokine-induced killer cells (CIKs) has been demonstrated to prolong the survival of patients with advanced non-small cell lung cancer (NSCLC). The aim of the present study was to evaluate whether the expansion of effector T cells and the decrease of regulatory T cells (Tregs) that occurred during the ex vivo generation of DC-CIKs were associated with improved clinical outcome in patients who received treatment. CIKs were generated ex vivo over a 28-day period from the peripheral blood apheresis product of 163 patients with advanced cancer (including 30 with NSCLC). CIKs were also generated from an additional cohort of 65 patients with NSCLC over a 15-day period. The progression-free survival (PFS) and overall survival (OS) time of patients treated with CIKs was determined by reviewing the patients' medical records. The number of CIKs gradually increased during the culture period and peaked at day 15, followed by a slight decline until day 28. Similarly, the percentages of T cell subtypes associated with anti-tumor activity (CD3⁺, CD3⁺CD4⁺, CD3⁺CD8⁺ and CD8⁺CD28⁺) peaked at day 15. Although the percentage of CD4⁺CD25⁺CD127⁺ Tregs increased by day 7, a decrease was subsequently observed. Among the 95 patients with NSCLC, those with a post/pre-culture ratio of CD8⁺CD28⁺ T lymphocytes >2.2 had significantly better PFS and OS compared with those with ratios ≤2.2. Those with a post/pre-culture CD4⁺CD25⁺CD127⁺ Treg ratio ≤0.6 had significantly better OS and PFS compared with those with ratios >0.6. The peak expansion of CIKs from peripheral blood mononuclear cells occurred at day 15 of ex vivo culture. PFS and OS were associated with post/pre-culture CD8⁺CD28⁺ T lymphocyte ratio >2.2 and post/pre-culture CD4⁺CD25⁺CD127⁺ Treg ratio <0.6 in the CIKs of patients with advanced NSCLC treated with adoptive T cell immunotherapy. Further efforts are underway to optimize the DC-CIK infusion for cancer immunotherapy.

Trial watch: dendritic cell vaccination for cancer immunotherapy

Dendritic- cells (DCs) have received considerable attention as potential targets for the development of anticancer vaccines. DC-based anticancer vaccination relies on patient-derived DCs pulsed with a source of tumor-associated antigens (TAAs) in the context of standardized maturation-cocktails, followed by their reinfusion. Extensive evidence has confirmed that DC-based vaccines can generate TAA-specific, cytotoxic T cells. Nonetheless, clinical efficacy of DC-based vaccines remains suboptimal, reflecting the widespread immunosuppression within tumors. Thus, clinical interest is being refocused on DC-based vaccines as combinatorial partners for T cell-targeting immunotherapies. Here, we summarize the most recent preclinical/clinical development of anticancer DC vaccination and discuss future perspectives for DC-based vaccines in immuno-oncology.

Increased glycolysis correlates with elevated immune activity in tumor immune microenvironment

Background

Prior studies showed that tumor glycolysis and tumor immune evasion are interdependent. However, a systematic investigation of the association between tumor glycolysis and tumor immunity in various cancers remains lacking.

Methods

Using the Cancer Genome Atlas (TCGA) datasets, we explored the association between glycolytic activity and immune signatures in 14 cancer types. We also explored the associations between glycolytic activity and tumor immunity associated genetic features, including PD-L1 expression, tumor mutation burden (TMB), and tumor aneuploidy. Moreover, we performed in vitro experiments to verify some findings from bioinformatics analysis. Furthermore, we explored the association between tumor glycolytic activity and immunotherapy response.

Findings

Glycolytic activity was likely correlated with active immune signatures in various cancers and highly glycolytic tumors presented an immune-stimulatory tumor microenvironment. Compared to TMB and aneuploidy, glycolytic activity was a stronger and more consistent predictor for immune signatures in diverse cancers. Both computational and experimental analyses showed that glycolysis could increase PD-L1 expression in tumor. Glycolytic activity had a strong correlation with apoptosis which was a strong positive predictor for immune signatures, suggesting that apoptosis could be an important medium connecting glycolytic activity with immune activity in cancer. Finally, highly glycolytic tumors exhibited a better immunotherapy response and a favorable survival in the immunotherapy setting.

Interpretation

Tumor glycolysis may increase tumor immunity in diverse cancers. Glycolytic activity enhances PD-L1 expression on tumor cells and thus promotes anti-PD-1/PD-L1 immunotherapy response. Thus, the tumor glycolytic activity could be a predictive biomarker for immunotherapy response in diverse cancers.

Fund

This work was supported by the China Pharmaceutical University (grant numbers 3150120001, 2632018YX01 to XW).