High expression of MAGE-A4 and MHC class I antigens in tumor cells and induction of MAGE-A4 immune responses are prognostic markers of CHP-MAGE-A4 cancer vaccine

Multi-omics analysis of overexpressed tumor-associated proteins: gene expression, immunopeptide presentation, and antibody response in oropharyngeal squamous cell carcinoma, with a focus on cancer-testis antigens

Introduction

The human leukocyte antigen complex (HLA) is essential for inducing specific immune responses to cancer by presenting tumor-associated peptides (TAP) to T cells. Overexpressed tumor associated antigens, mainly cancer-testis antigens (CTA), are outlined as essential targets for immunotherapy in oropharyngeal squamous cell carcinoma (OPSCC). This study assessed the degree to which presentation, gene expression, and antibody response (AR) of TAP, mainly CTA, are correlated in OPSCC patients to evaluate their potential as immunotherapy targets.

Materials and methods

Snap-frozen tumor (NLigand/RNA=40), healthy mucosa (NRNA=6), and healthy tonsils (NLigand=5) samples were obtained. RNA-Seq was performed using Illumina HiSeq 2500/NovaSeq 6000 and whole exome sequencing (WES) utilizing NextSeq500. HLA ligands were isolated from tumor tissue using immunoaffinity purification, UHPLC, and analyzed by tandem MS. Antibodies were measured in serum (NAb=27) utilizing the KREX™ CT262 protein array. Data analysis focused on 312 proteins (KREX™ CT262 panel + overexpressed self-proteins).

Results

183 and 94 of HLA class I and II TAP were identified by comparative profiling with healthy tonsils. Genes from 26 TAP were overexpressed in tumors compared to healthy mucosa (LFC>1; FDR<0.05). Low concordance (r=0.25; p<0.0001) was found between upregulated mRNA and class I TAP. The specific mode of correlation of TAP was found to be dependent on clinical parameters. A lack of correlation was observed both between mRNA and class II TAP, as well as between class II tumor-unique TAP (TAP-U) presentation and antibody response (AR) levels.

Discussion

This study demonstrates that focusing exclusively on gene transcript levels fails to capture the full extent of TAP presentation in OPSCC. Furthermore, our findings reveal that although CTA are presented at relatively low levels, a few CTA TAP-U show potential as targets for immunotherapy.

MAGE-A4-Responsive Plasma Cells Promote Non-Small Cell Lung Cancer

Adaptive immunity is critical to eliminate malignant cells, while multiple tumor-intrinsic factors can alter this protective function. Melanoma antigen-A4 (MAGE-A4), a cancer-testis antigen, is expressed in several solid tumors and correlates with poor survival in non-small cell lung cancer (NSCLC), but its role in altering antitumor immunity remains unclear. We found that expression of MAGE-A4 was highly associated with the loss of PTEN , a tumor suppressor, in human NSCLC. Here we show that constitutive expression of human MAGE-A4 combined with the loss of Pten in mouse airway epithelial cells results in metastatic adenocarcinoma enriched in CD138 + CXCR4 + plasma cells, predominantly expressing IgA. Consistently, human NSCLC expressing MAGE-A4 showed increased CD138 + IgA + plasma cell density surrounding tumors. The abrogation of MAGE-A4-responsive plasma cells (MARPs) decreased tumor burden, increased T cell infiltration and activation, and reduced CD163 + CD206 + macrophages in mouse lungs. These findings suggest MAGE-A4 promotes NSCLC tumorigenesis, in part, through the recruitment and retention of IgA + MARPs in the lungs.

Recent advances in stimuli-responsive tailored nanogels for cancer therapy; from bench to personalized treatment

To improve the quality of health in a personalized manner, better control over pharmacologically relevant cargo formulation, organ-specific targeted delivery, and on-demand release of therapeutic agents is crucial. Significant work has been put into designing and developing revolutionary nanotherapeutics approaches for the effective monitoring and personalized treatment of disease. Nanogel (NG) has attracted significant interest because of its tremendous potential in cancer therapy and its environmental stimuli responsiveness. NG is considered a next-generation delivery technology due to its benefits like as size tunability, high loading, stimuli responsiveness, prolonged drug release via in situ gelling mechanisms, stability, and its potential to provide personalized therapy from the investigation of human genes and the genes in various types of cancers and its association with a selective anticancer drug. Stimuli-responsive NGs can be used as smart nanomedicines to detect and treat cancer and can be tuned as personalized medicine as well. This comprehensive review article's major objectives include the challenges of NGs' clinical translation for cancer treatment as well as its early preclinical successes and prospects.

Expression of four cancer-testis antigens in TNBC indicating potential universal immunotherapeutic targets

OBJECTIVE

Immunotherapy is an attractive treatment for breast cancer. Cancer-testis antigens (CTAs) are potential targets for immunotherapy for their restricted expression. Here, we investigate the expression of CTAs in breast cancer and their value for prognosis. So as to hunt for a potential panel of CTAs for universal immunotherapeutic targets.

MATERIAL AND METHODS

A total of 137 breast cancer tissue specimens including 51 triple-negative breast cancer (TNBC) were assessed for MAGE-A4, MAGEA1, NY-ESO-1, KK-LC-1 and PRAME expression by immunohistochemistry. The expression of PD-L1 and TILs was also calculated and correlated with the five CTAs. Clinical data were collected to evaluate the CTA's value for prognosis. Data from the K-M plotter were used as a validation cohort.

RESULTS

The expression of MAGE-A4, NY-ESO-1 and KK-LC-1 in TNBC was significantly higher than in non-TNBC (P = 0.012, P = 0.005, P < 0.001 respectively). 76.47% of TNBC expressed at least one of the five CTAs. Patients with positive expression of either MAGE-A4 or PRAME had a significantly extended disease-free survival (DFS). Data from the Kaplan-Meier plotter confirm our findings.

CONCLUSIONS

MAGE-A4, NY-ESO-1, PRAME and KK-LC-1 are overexpressed in breast cancer, especially in TNBC. Positive expression of MAGE-A4 or PARME may be associated with prolonged DFS. A panel of CTAs is attractive universal targets for immunotherapy.

Integrated analysis of phase 1a and 1b randomized controlled trials; Treg-targeted cancer immunotherapy with the humanized anti-CCR4 antibody, KW-0761, for advanced solid tumors

INTRODUCTION

Regulatory T cells (Tregs) have attracted attention as a novel therapeutic target to augment the clinical efficacy of immunotherapy. We conducted phase Ia and Ib trials to examine the safety and efficacy of the anti-CCR4 antibody, KW-0761 (mogamulizumab), which may eliminate effector Tregs (eTregs). We herein overviewed the results of these trials, presented cases with a durable clinical response, and investigated factors associated with the clinical effects of KW-0761.

METHODS

Forty-nine patients with CCR4-negative solid cancers were enrolled in the phase Ia and Ib trials on KW-0761. An integral analysis of safety, clinical responses, prognosis, blood laboratory data, and cancer testis antigen-specific immune responses was performed.

RESULTS

Grade 3-4 treatment-related adverse events were reported in 21 (42.9%) out of 49 patients, all of which were manageable. A partial response and stable disease were observed in 1 and 9 patients, respectively. A durable clinical response was noted in 2 esophageal and 2 lung cancer patients. eTreg depletion in peripheral blood was confirmed in most patients, and eTreg depletion was sustained during the KW-0761 treatment. High lymphocyte levels at baseline and 2 weeks after the initiation of KW-0761 were associated with a favorable clinical outcome.

CONCLUSIONS

A durable clinical response was noted in some patients, and high lymphocyte levels before treatment initiation may be a biomarker for the efficacy of KW-0761. The synergistic effect of KW-0761 for depleting Tregs and other immunotherapies is expected in the future.

Structural analysis of cancer-relevant TCR-CD3 and peptide-MHC complexes by cryoEM

The recognition of antigenic peptide-MHC (pMHC) molecules by T-cell receptors (TCR) initiates the T-cell mediated immune response. Structural characterization is key for understanding the specificity of TCR-pMHC interactions and informing the development of therapeutics. Despite the rapid rise of single particle cryoelectron microscopy (cryoEM), x-ray crystallography has remained the preferred method for structure determination of TCR-pMHC complexes. Here, we report cryoEM structures of two distinct full-length α/β TCR-CD3 complexes bound to their pMHC ligand, the cancer-testis antigen HLA-A2/MAGEA4 (230-239). We also determined cryoEM structures of pMHCs containing MAGEA4 (230-239) peptide and the closely related MAGEA8 (232-241) peptide in the absence of TCR, which provided a structural explanation for the MAGEA4 preference displayed by the TCRs. These findings provide insights into the TCR recognition of a clinically relevant cancer antigen and demonstrate the utility of cryoEM for high-resolution structural analysis of TCR-pMHC interactions.

Emerging targeted and cellular therapies in the treatment of advanced and metastatic synovial sarcoma

Synovial sarcoma is a soft tissue sarcoma accounting for approximately 1,000 cases per year in the United States. Currently, standard treatment of advanced and metastatic synovial sarcoma is anthracycline-based chemotherapy. While advanced synovial sarcoma is more responsive to chemotherapy compared to other soft tissue sarcomas, survival rates are poor, with a median survival time of less than 18 months. Enhanced understanding of tumor antigen expression and molecular mechanisms behind synovial sarcoma provide potential targets for treatment. Adoptive Cell Transfer using engineered T-cell receptors is in clinical trials for treatment of synovial sarcoma, specifically targeting New York esophageal squamous cell carcinoma-1 (NY-ESO-1), preferentially expressed antigen in melanoma (PRAME), and melanoma antigen-A4 (MAGE-A4). In this review, we explore the opportunities and challenges of these treatments. We also describe artificial adjuvant vector cells (aAVCs) and BRD9 inhibitors, two additional potential targets for treatment of advanced synovial sarcoma. This review demonstrates the progress that has been made in treatment of synovial sarcoma and highlights the future study and qualification needed to implement these technologies as standard of care.

Challenges and exploration for immunotherapies targeting cold colorectal cancer

In recent years, immune checkpoint inhibitors (ICIs) have made significant breakthroughs in the treatment of various tumors, greatly improving clinical efficacy. As the fifth most common antitumor treatment strategy for patients with solid tumors after surgery, chemotherapy, radiotherapy and targeted therapy, the therapeutic response to ICIs largely depends on the number and spatial distribution of effector T cells that can effectively identify and kill tumor cells, features that are also important when distinguishing malignant tumors from “cold tumors” or “hot tumors”. At present, only a small proportion of colorectal cancer (CRC) patients with deficient mismatch repair (dMMR) or who are microsatellite instability-high (MSI-H) can benefit from ICI treatments because these patients have the characteristics of a “hot tumor”, with a high tumor mutational burden (TMB) and massive immune cell infiltration, making the tumor more easily recognized by the immune system. In contrast, a majority of CRC patients with proficient MMR (pMMR) or who are microsatellite stable (MSS) have a low TMB, lack immune cell infiltration, and have almost no response to immune monotherapy; thus, these tumors are “cold”. The greatest challenge today is how to improve the immunotherapy response of “cold tumor” patients. With the development of clinical research, immunotherapies combined with other treatment strategies (such as targeted therapy, chemotherapy, and radiotherapy) have now become potentially effective clinical strategies and research hotspots. Therefore, the question of how to promote the transformation of “cold tumors” to “hot tumors” and break through the bottleneck of immunotherapy for cold tumors in CRC patients urgently requires consideration. Only by developing an in-depth understanding of the immunotherapy mechanisms of cold CRCs can we screen out the immunotherapy-dominant groups and explore the most suitable treatment options for individuals to improve therapeutic efficacy.

Recent Advances in the Biomedical Applications of Functionalized Nanogels

Nanomaterials have been extensively used in several applications in the past few decades related to biomedicine and healthcare. Among them, nanogels (NGs) have emerged as an important nanoplatform with the properties of both hydrogels and nanoparticles for the controlled/sustained delivery of chemo drugs, nucleic acids, or other bioactive molecules for therapeutic or diagnostic purposes. In the recent past, significant research efforts have been invested in synthesizing NGs through various synthetic methodologies such as free radical polymerization, reversible addition-fragmentation chain-transfer method (RAFT) and atom transfer radical polymerization (ATRP), as well as emulsion techniques. With further polymeric functionalizations using activated esters, thiol-ene/yne processes, imines/oximes formation, cycloadditions, nucleophilic addition reactions of isocyanates, ring-opening, and multicomponent reactions were used to obtain functionalized NGs for targeted delivery of drug and other compounds. NGs are particularly intriguing for use in the areas of diagnosis, analytics, and biomedicine due to their nanodimensionality, material characteristics, physiological stability, tunable multi-functionality, and biocompatibility. Numerous NGs with a wide range of functionalities and various external/internal stimuli-responsive modalities have been possible with novel synthetic reliable methodologies. Such continuous development of innovative, intelligent materials with novel characteristics is crucial for nanomedicine for next-generation biomedical applications. This paper reviews the synthesis and various functionalization strategies of NGs with a focus on the recent advances in different biomedical applications of these surface modified/functionalized single-/dual-/multi-responsive NGs, with various active targeting moieties, in the fields of cancer theranostics, immunotherapy, antimicrobial/antiviral, antigen presentation for the vaccine, sensing, wound healing, thrombolysis, tissue engineering, and regenerative medicine.

Physically stimulus-responsive nanoparticles for therapy and diagnosis

Nanoparticles offer numerous advantages in various fields of science, particularly in medicine. Over recent years, the use of nanoparticles in disease diagnosis and treatments has increased dramatically by the development of stimuli-responsive nano-systems, which can respond to internal or external stimuli. In the last 10 years, many preclinical studies were performed on physically triggered nano-systems to develop and optimize stable, precise, and selective therapeutic or diagnostic agents. In this regard, the systems must meet the requirements of efficacy, toxicity, pharmacokinetics, and safety before clinical investigation. Several undesired aspects need to be addressed to successfully translate these physical stimuli-responsive nano-systems, as biomaterials, into clinical practice. These have to be commonly taken into account when developing physically triggered systems; thus, also applicable for nano-systems based on nanomaterials. This review focuses on physically triggered nano-systems (PTNSs), with diagnostic or therapeutic and theranostic applications. Several types of physically triggered nano-systems based on polymeric micelles and hydrogels, mesoporous silica, and magnets are reviewed and discussed in various aspects.

Nanogels as target drug delivery systems in cancer therapy: A review of the last decade

Cancer is an important cause of morbidity and mortality worldwide, irrespective of the level of human development. Globally, it was estimated that there were 19.3 million new cases of cancer and almost 10 million deaths from cancer in 2020. The importance of prevention, early detection as well as effective cancer therapies cannot be over-emphasized. One of the important strategies in cancer therapy is targeted drug delivery to the specific tumor sites. Nanogels are among the several drug delivery systems (DDS) being explored as potential candidates for targeted drug delivery in cancer therapy. Nanogels, which are new generation, versatile DDS with the possession of dual characteristics of hydrogels and nanoparticles have shown great potential as targeted DDS in cancer therapy. Nanogels are hydrogels with a three-dimensional (3D) tunable porous structure and a particle size in the nanometre range, from 20 to 200 nm. They have been visualized as ideal DDS with enormous drug loading capacity, and high stability. Nanogels can be modified to achieve active targeting and enhance drug accumulation in disease sites. They can be designed to be stimulus-responsive, and react to internal or external stimuli such as pH, temperature, light, redox, thus resulting in the controlled release of loaded drug. This prevents drug accumulation in non-target tissues and minimizes the side effects of the drug. Drugs with severe adverse effects, short circulation half-life, and easy degradability by enzymes, such as anti-cancer drugs, and proteins, are suitable for delivery by chemically cross-linked or physically assembled nanogel systems. This systematic review summarizes the evolution of nanogels for targeted drug delivery for cancer therapy over the last decade. On-going clinical trials and recent applications of nanogels as targeted DDS for cancer therapy will be discussed in detail. The review will be concluded with discussions on safety and regulatory considerations as well as future research prospects of nanogel-targeted drug delivery for cancer therapy.

Clinicopathological assessment of cancer/testis antigens NY‑ESO‑1 and MAGE‑A4 in osteosarcoma

The cancer/testis antigens (CTAs), New York esophageal squamous cell carcinoma-1 (NY-ESO-1) and melanoma antigen gene (MAGE)-A4 are normally restricted to male germ cells but are aberrantly expressed in several cancers. Considering the limited information regarding their significance in osteosarcoma (OS), the purpose of this study was to determine the clinical significance of NY-ESO-1 and MAGE-A4 expression in OS. Nine patients with OS treated at Kindai University Hospital were included in the study. The median age was 27 years, and median follow-up period was 40 months. The specimens obtained at the time of biopsy were used to perform immunostaining for NY-ESO, MAGE-A4, p53, and Ki-67. The positive cell rates and positive case rates of NY-ESO, MAGE-A4, p53, and Ki-67 were calculated. The correlation between the positive cell rate of immunohistochemical markers was also calculated. The correlation between the positive cell rate of NY-ESO-1 or MAGE-A4 and tumor size or maximum standardized uptake (SUV-max) was also determined. The positive cell rates of NY-ESO-1 or MAGE-A4 in continuous disease-free (CDF) cases were also compared with those in alive with disease (AWD) or dead of disease (DOD) cases. The average positive cell rates of NY-ESO, MAGEA4, p53, and Ki-67 were 71.7%, 85.1%, 16.2%, and 14.7%, and their positive case rates were 33.3%, 100%, 44.4%, and 100%, respectively. The positivity rates of NY-ESO-1 and p53 were strongly correlated, whereas those of NY-ESO-1 and Ki-67 were moderately correlated. The MAGE-A4 and p53 positivity rates and the MAGE-A4 and Ki-67 positive cell rates were both strongly correlated. The NY-ESO-1 and MAGE-A4 positivity rates were moderately correlated. The positive correlation between the NY-ESO-1 positive cell rate and tumor size was medium, and that between the MAGE-A4 positivity rate and SUV-max was very strong. There was no significant difference in the positive cell rates of NY-ESO-1 or MAGE-A4 between CDF cases and AWD or DOD cases. Overall, our results suggest that NY-ESO-1 and MAGE-A4 may be involved in the aggressiveness of OS.

Immunohistochemical expression and clinicopathological assessment of PD-1, PD-L1, NY-ESO-1, and MAGE-A4 expression in highly aggressive soft tissue sarcomas

Immunotherapy has altered the treatment paradigm for soft tissue sarcomas (STSs). Considering the limited information regarding the clinical significance of immunohistochemical markers in STS, the purpose of this study was to determine the clinical significance of programmed cell death-1 (PD-1), PD ligand-1(PD-L1), New York esophageal squamous cell carcinoma-1 (NY-ESO-1), and melanoma-associated antigen-A4 (MAGE-A4) expression in STSs. Twenty-two patients (median age, 72.5 years) with STSs treated at our hospital were included in this study. The specimens obtained at the time of biopsy were used to perform immunostaining for PD-1, PD-L1, NY-ESO, and MAGE-A4. The rates of PD-1-, PD-L1-, NY-ESO-, and MAGE-A4-positive cells and cases were calculated. The correlations among the positive cell rates of the immunohistochemical markers as well as their correlations with the histological grade, tumor size, or maximum standardized uptake (SUVmax) value were also determined. The average rates of PD-1-, PD-L1-, NY-ESO-, and MAGE-A4-positive cells were 4.39%, 28.0%, 18.2%, and 39.4%, respectively. PD-1-, PD-L1-, NY-ESO-1-, and MAGE-A4- positive cell rates showed weak to strong correlations with the SUVmax value. Thus, PD-1, PD-L1, NY-ESO, and MAGE-A4 expressions might be involved in the aggressive elements of STSs.

Clinicopathological Assessment of Cancer/Testis Antigens NY-ESO-1 and MAGE-A4 in Highly Aggressive Soft Tissue Sarcomas

We aimed to investigate the clinical significance of the expression of NY-ESO-1 and MAGE-A4 in soft tissue sarcoma (STS). Immunostaining for NY-ESO-1, MAGE-A4, and Ki67 was performed using pathological specimens harvested from 10 undifferentiated pleomorphic sarcoma (UPS), nine myxofibrosarcoma (MFS), and three malignant peripheral nerve sheath tumor (MPNST) patients treated at our hospital. We examined the correlation of NY-ESO-1 and MAGE-A4 expression levels with tumor size, histological grade, and SUVmax values. Positive cell rates of various markers were also compared between patients in remission and those who were not in remission. The rates of cases positive for NY-ESO, MAGE-A4, and Ki67 were 50%, 63.6%, and 90.9%, respectively. The average rates of cells positive for NY-ESO, MAGE-A4, and Ki67 in all STS types were 18.2%, 39.4%, and 16.8%, respectively. A positive correlation was observed between rates of cells positive for NY-ESO-1 and MAGE-A4 and between NY-ESO-1 and MAGE-A4 expression levels and clinical features. There was no significant difference in the positive cell rate of NY-ESO-1 or MAGE-A4 between remission and non-remission cases. Our results suggest that NY-ESO-1 and MAGE-A4 expression may be useful for the diagnosis and prognostication of UPS, MFS, and MPNST.

In vitro assessment of antitumor immune responses using tumor antigen proteins produced by transgenic silkworms

The evaluation of antitumor immune responses is essential for immune monitoring to predict clinical outcomes as well as treatment efficacies in cancer patients. In this study, we produced two tumor antigen (TA) proteins, melanoma antigen family A4 and wild type p53, using TG silkworm systems and evaluated anti-TA-specific immune responses by enzyme-linked immunosorbent spot assays in patients with head and neck cancer. Eleven (61.1%) of 18 patients showed significant IFN-γ production in response to at least one TA; however, the presence of TA-specific immune responses did not significantly contribute to better prognosis (overall survival, p = 0.1768; progression-free survival, p = 0.4507). Further studies will need to be performed on a larger scale to better assess the clinical significance of these systems. The production of multiple TA proteins may provide new avenues for the development of immunotherapeutic strategies to stimulate a potent and specific immune response against tumor cells as well as precise assessment of antitumor immune responses in cancer patients.

Understanding the immuno-biology of oesophageal adenocarcinoma: Towards improved therapeutic approaches

With an incidence that is constantly rising, oesophageal adenocarcinoma (OAC) is becoming an increasing health burden worldwide. Although significant advances in treatment regimens have improved patient outcomes, survival rates for this deadly cancer remain unsatisfactory. This highlights the need to improve current therapeutic approaches and develop novel therapeutic strategies for treating OAC patients. The advent of immunotherapy has revolutionised treatment across a range of malignancies, however outcomes in OAC show modest results. The inherent resistance of OAC to treatment reflects the complex genomic landscape of this cancer, which displays a lack of ubiquitous driver mutations and large-scale genomic alterations along with high tumour and immune heterogeneity. Research into the immune landscape of OAC is limited, and elucidation of the mechanisms surrounding the immune responses to this complex cancer will result in improved therapeutic approaches. This review explores what is known about the immuno-biology of OAC and explores promising therapeutic avenues that may improve responses to immunotherapeutic regimens.

Proteomic signatures of 16 major types of human cancer reveal universal and cancer-type-specific proteins for the identification of potential therapeutic targets

Background

Proteomic characterization of cancers is essential for a comprehensive understanding of key molecular aberrations. However, proteomic profiling of a large cohort of cancer tissues is often limited by the conventional approaches.

Methods

We present a proteomic landscape of 16 major types of human cancer, based on the analysis of 126 treatment-naïve primary tumor tissues, 94 tumor-matched normal adjacent tissues, and 12 normal tissues, using mass spectrometry-based data-independent acquisition approach.

Results

In our study, a total of 8527 proteins were mapped to brain, head and neck, breast, lung (both small cell and non-small cell lung cancers), esophagus, stomach, pancreas, liver, colon, kidney, bladder, prostate, uterus and ovary cancers, including 2458 tissue-enriched proteins. Our DIA-based proteomic approach has characterized major human cancers and identified universally expressed proteins as well as tissue-type-specific and cancer-type-specific proteins. In addition, 1139 therapeutic targetable proteins and 21 cancer/testis (CT) antigens were observed.

Conclusions

Our discoveries not only advance our understanding of human cancers, but also have implications for the design of future large-scale cancer proteomic studies to assist the development of diagnostic and/or therapeutic targets in multiple cancers.

Nanoparticles guided drug delivery and imaging in gastric cancer

Gastric cancer represents a deadly malignancy worldwide, yet current therapeutic regimens remain ineffective. Nanoparticle (NP) -based solutions could allow the design of novel therapeutic methods to eliminate this fatal disease. NPs typically carry out a significant role in multifunctional, multimodal imaging, and drug delivery carriers. In the recent decade, they have emerged as candidate approaches for the design of novel treatment strategies. Tumor nanotherapeutics characteristically possess various distinct advantages compared to conventional anti-cancer medications, which suffer from nonspecific bio-distribution, low solubility, and poor bioavailability. In this review, we will discuss the application of NPs in diagnosis and controlled drug delivery in gastric cancer (GC). We will focus on various NPs-based strategies employed against GC.

BCMA peptide-engineered nanoparticles enhance induction and function of antigen-specific CD8+ cytotoxic T lymphocytes against multiple myeloma: clinical applications

The purpose of these studies was to develop and characterize B-cell maturation antigen (BCMA)-specific peptide-encapsulated nanoparticle formulations to efficiently evoke BCMA-specific CD8+ cytotoxic T lymphocytes (CTL) with poly-functional immune activities against multiple myeloma (MM). Heteroclitic BCMA72-80 [YLMFLLRKI] peptide-encapsulated liposome or poly(lactic-co-glycolic acid) (PLGA) nanoparticles displayed uniform size distribution and increased peptide delivery to human dendritic cells, which enhanced induction of BCMA-specific CTL. Distinct from liposome-based nanoparticles, PLGA-based nanoparticles demonstrated a gradual increase in peptide uptake by antigen-presenting cells, and induced BCMA-specific CTL with higher anti-tumor activities (CD107a degranulation, CTL proliferation, and IFN-γ/IL-2/TNF-α production) against primary CD138+ tumor cells and MM cell lines. The improved functional activities were associated with increased Tetramer+/CD45RO+ memory CTL, CD28 upregulation on Tetramer+ CTL, and longer maintenance of central memory (CCR7+ CD45RO+) CTL, with the highest anti-MM activity and less differentiation into effector memory (CCR7- CD45RO+) CTL. These results provide the framework for therapeutic application of PLGA-based BCMA immunogenic peptide delivery system, rather than free peptide, to enhance the induction of BCMA-specific CTL with poly-functional Th1-specific anti-MM activities. These results demonstrate the potential clinical utility of PLGA nanotechnology-based cancer vaccine to enhance BCMA-targeted immunotherapy against myeloma.

Crossing biological barriers with nanogels to improve drug delivery performance

The current limitations in the use of nanocarriers to treat constantly evolving diseases call for the design of novel and smarter drug delivery systems (DDS). Nanogels (NGs) are three-dimensional crosslinked polymers with dimensions on the nanoscale and with a great potential for use in the biomedical field. Particular interest focuses on their application as DDS to minimize severe toxic effects and increase the therapeutic index of drugs. They have recently gained attention, since they can include responsive modalities within their structure, which enable them to excerpt a therapeutic function on demand. Their bigger sizes and controlled architecture and functionality, when compared to non-crosslinked polymers, make them particularly interesting to explore novel modalities to cross biological barriers. The present review summarizes the most significant developments of NGs as smart carriers, with focus on smart modalities to cross biological barriers such as cellular membrane, tumor stroma, mucose, skin, and blood brain barrier. We discuss the properties of each barrier and highlight the importance that the NG design has on their capability to overcome them and deliver the cargo at the site of action.

Immunohistochemical expression and clinicopathological assessment of the cancer testis antigens NY-ESO-1 and MAGE-A4 in high-grade soft-tissue sarcoma

The aim of the present study was to explore the expression of the cancer testis antigens New York-esophageal squamous cell carcinoma (NY-ESO)-1 and melanoma-associated antigen (MAGE)-A4 in high-grade soft-tissue sarcoma and to evaluate their association with the standard clinical-pathological features of surgically treated high-grade sarcoma patients. The study included 82 patients, and NY-ESO-1 and MAGE-A4 antigen expression was analyzed immunohistochemically. The results revealed NY-ESO-1- and MAGE-A4-positive staining in 58.8 and 52.9% of synovial sarcomas, and 55.6 and 0% of myxoid liposarcomas, respectively. In patients with synovial sarcoma, NY-ESO-1 and MAGE-A4 were expressed in 7 patients, only NY-ESO-1 was expressed in 3 patients, and only MAGE-A4 was expressed in 2 patients. Univariate analysis indicated that a significantly higher MAGE-A4 expression was observed in younger patients (P<0.001) and those with synovial sarcoma (P<0.001). Multivariate analysis indicated that significantly higher NY-ESO-1 expression was observed in patients with synovial sarcoma (P<0.01) and myxoid liposarcoma (P<0.01), and significantly higher MAGE-A4 expression was observed in patients with synovial sarcoma (P<0.01). In high-grade sarcomas, the 2- and 5-year overall survival rates based on Kaplan-Meier estimates were 100 and 81.3% in the NY-ESO-1-positive group, and 69.7 and 53.0% in the NY-ESO-1-negative group, respectively (P=0.049). It was also demonstrated that either NY-ESO-1 or MAGE-A4 was positive in 70.6% of synovial sarcomas. These results indicate that NY-ESO-1 and MAGE-A4 may be useful for the diagnosis of synovial sarcoma. The independent expression of NY-ESO-1 and MAGE-A4, which may help expand the pool of candidates for molecular-targeted immunotherapy, will be beneficial for synovial sarcoma patients.

Hybrid Nanogels: Stealth and Biocompatible Structures for Drug Delivery Applications

Considering nanogels, we have focused our attention on hybrid nanosystems for drug delivery and biomedical purposes. The distinctive strength of these structures is the capability to join the properties of nanosystems with the polymeric structures, where versatility is strongly demanded for biomedical applications. Alongside with the therapeutic effect, a non-secondary requirement of the nanosystem is indeed its biocompatibility. The importance to fulfill this aim is not only driven by the priority to reduce, as much as possible, the inflammatory or the immune response of the organism, but also by the need to improve circulation lifetime, biodistribution, and bioavailability of the carried drugs. In this framework, we have therefore gathered the hybrid nanogels specifically designed to increase their biocompatibility, evade the recognition by the immune system, and overcome the self-defense mechanisms present in the bloodstream of the host organism. The works have been essentially organized according to the hybrid morphologies and to the strategies adopted to fulfill these aims: Nanogels combined with nanoparticles or with liposomes, and involving polyethylene glycol chains or zwitterionic polymers.

NY-ESO-1 antigen expression and immune response are associated with poor prognosis in MAGE-A4-vaccinated patients with esophageal or head/neck squamous cell carcinoma

MAGE-A4 antigen is a cancer-testis antigen that is frequently expressed in tumor tissues. Cholesteryl pullulan (CHP) is a novel antigen delivery system for cancer vaccines. This study evaluated the safety, immune responses and clinical outcomes of patients who received a CHP-MAGE-A4 vaccine. Twenty-two patients with advanced or metastatic cancer were enrolled, and were subcutaneously vaccinated with either 100 μg or 300 μg of CHP-MAGE-A4. Seven and 15 patients, respectively, were repeatedly vaccinated with 100 μg or 300 μg of CHP-MAGE-A4; patients in both groups received a median of 7 doses. No serious adverse events related to the vaccine were observed. Of 7 patients receiving the 100 μg dose, 2 (29%) showed immune responses, compared with 3 of the 14 (21%) patients who received the 300 μg dose. In total, MAGE-A4-specific antibody responses were induced in 5 of 21 (24%) patients. No differences in survival were seen between patients receiving the 100 μg and 300 μg doses, or between immune responders and non-responders. Eleven (50%) patients had pre-existing antibodies to NY-ESO-1. In 16 patients with esophageal or head/neck squamous cell carcinoma, the survival time was significantly shorter in those who had NY-ESO-1-co-expressing tumors. Patients with high pre-existing antibody responses to NY-ESO-1 displayed worse prognosis than those with no pre-existing response. Therefore, in planning clinical trials of MAGE-A4 vaccine, enrolling NY-ESO-1-expressing tumor or not would be a critical issue to be discussed. Combination vaccines of MAGE-A4 and NY-ESO-1 antigens would be one of the strategies to overcome the poor prognosis.

Research progress of self-assembled nanogel and hybrid hydrogel systems based on pullulan derivatives

Polymer nano-sized hydrogels (nanogels) as drug delivery carriers have been investigated over the last few decades. Pullulan, a nontoxic and nonimmunogenic hydrophilic polysaccharide derived from fermentation of black yeast like Aureobasidium pullulans with great biocompatibility and biodegradability, is one of the most attractive carriers for drug delivery systems. In this review, we describe the preparation, characterization, and 'switch-on/off' mechanism of typical pullulan self-assembled nanogels (self-nanogels), and then introduce the development of hybrid hydrogels that are numerous resources applied for regenerative medicine. A major section is used for biomedical applications of different nanogel systems based on modified pullulan, which exert smart stimuli-responses at ambient conditions such as charge, pH, temperature, light, and redox. Pullulan self-nanogels have found increasingly extensive application in protein delivery, tissue engineering, vaccine development, cancer therapy, and biological imaging. Functional groups are incorporated into self-nanogels and contribute to expressing desirable results such as targeting and modified release. Various molecules, especially insoluble or unstable drugs and encapsulated proteins, present improved solubility and bioavailability as well as reduced side effects when incorporated into self-nanogels. Finally, the advantages and disadvantages of pullulan self-nanogels will be analyzed accordingly, and the development of pullulan nanogel systems will be reviewed.

Immunotherapy for esophageal squamous cell carcinoma: a review

Cancer vaccines and immune checkpoint inhibitors (ICI) have recently been employed as immunotherapies for esophageal squamous cell carcinoma (ESCC). Cancer vaccines for ESCC have yielded several promising results from investigator-initiated phase I and II clinical trials. Furthermore, a Randomized Controlled Trial as an adjuvant setting after curative surgery is in progress in Japan. On the other hand, ICI, anti-CTLA-4 mAb and anti-PD-1 mAb, have demonstrated tumor shrinkage and improved overall survival in patients with multiple cancer types. For ESCC, several clinical trials using anti-PD-1/anti-PD-L1 mAb are underway with several recent promising results. In this review, cancer vaccines and ICI are discussed as novel therapeutic strategies for ESCC.

Prognostic value of MAGEA4 in primary lung cancer depends on subcellular localization and p53 status

Melanoma antigen family A4 (MAGEA4), a cancer/testis antigen, is overexpressed and is thus an immunotherapy target in various malignant tumors, including non-small cell lung cancer. However, whether MAGEA4 induces or inhibits the apoptosis of lung cancer cells remains controversial, as is its prognostic significance, particularly since there is no reliable method with which to detect MAGEA4 specifically. In this study, we optimized assay conditions to detect MAGEA4 based on cells transiently transfected with MAGEA genes, and found that MAGEA4 was expressed in four of eight non-small cell lung cancer cell lines, and in 25.4% of clinical lung cancer specimens. We also found that MAGEA4 overexpression decreased apoptosis, as measured by the levels of cleaved caspase-3 in stably transfected 293F cells. Notably, patients with nuclear MAGEA4, but not p53 expression exhibited a significantly poorer survival than those expressing both nuclear MAGEA4 and p53. Indeed, multivariate analysis identified nuclear MAGEA4 as an independent prognostic factor (P=0.0042), albeit only in the absence of p53. In this study, to the best of our knowledge, we are the first to demonstrate that the function and prognostic value of MAGEA4 depends on its subcellular localization and on the p53 status.

Antibody response against cancer-testis antigens MAGEA4 and MAGEA10 in patients with melanoma

Melanoma-associated antigen A (MAGEA) represent a class of tumor antigens that are expressed in a variety of malignant tumors, however, their expression in healthy normal tissues is restricted to germ cells of testis, fetal ovary and placenta. The restricted expression and immunogenicity of these antigens make them ideal targets for immunotherapy in human cancer. In the present study the presence of naturally occurring antibodies against two MAGEA subfamily proteins, MAGEA4 and MAGEA10, was analyzed in patients with melanoma at different stages of disease. Results indicated that the anti-MAGEA4/MAGEA10 immune response in melanoma patients was heterogeneous, with only ~8% of patients having a strong response. Comparing the number of strongly responding patients between different stages of disease revealed that the highest number of strong responses was detected among stage II melanoma patients. These findings support the model that the immune system is involved in the control of melanoma in the early stages of disease.

Cancer-testis antigens are predominantly expressed in uterine leiomyosarcoma compared with non-uterine leiomyosarcoma

Leiomyosarcomas account for ~24% of all adult sarcomas, and develop predominantly either in the uterus [uterine leiomyosarcoma (ULMS)] or in deep soft tissue or the retroperitoneum [non-uterine leiomyosarcoma (NULMS)]. Leiomyosarcomas are relatively chemoresistant tumors, and the prognosis of patients with leiomyosarcomas is poor. Cancer-testis (CT) antigens are considered promising immunotherapeutic targets because of their restricted expression in normal tissue, except in the testis. Little is known about the expression of CT antigens in leiomyosarcomas. In the present study, the protein expression of the CT antigens MAGE family member A (MAGEA)1, MAGEA3, MAGEA4, G antigen 7 (GAGE7) and cancer/testis antigen 1 (NY-ESO-1) in ULMS and NULMS were investigated using immunohistochemistry (IHC), and their expression profiles compared. In ULMS and NULMS, positive expression was observed in 11/32 (31%) and 1/31 (3%; MAGEA1), 15/32 (47%) and 5/31 (16%; MAGEA3), 11/32 (34%) and 3/31 (10%; MAGEA4), 23/32 (72%) and 11/31 (35%; GAGE7) and 3/32 (9%) and 0/31 (0%; NY-ESO-1), respectively. The ULMSs demonstrated significantly higher positive expression of MAGEA1 (P=0.0034), MAGEA3 (P=0.0141), MAGEA4 (P=0.0319) and GAGE7 (P=0.0054) compared with the NULMSs. The ULMSs also had significantly higher IHC scores for MAGEA1 (P=0.0023), MAGEA3 (P=0.0474), MAGEA4 (P=0.011), GAGE7 (P=0.0319) and NY-ESO-1 (P=0.0437). The results of the present study support the potential utility of MAGEA1, MAGEA3, MAGEA4 and GAGE7 in ULMS and GAGE7 in NULMS as immunotherapeutic targets.

Melanoma antigen family A4 protein produced by transgenic silkworms induces antitumor immune responses

Recent clinical trials with the aim of developing tumor antigen (TA)-specific cancer vaccines against a number of malignancies have focused on the identification of TAs presented by tumor cells and recognized by T cells. In the present study, the TA melanoma antigen family A4 (MAGE-A4) protein was produced using a transgenic (TG) silkworm system. Using in vitro stimulation, it was subsequently determined whether MAGE-A4 protein induced MAGE-A4-specific T cells from peripheral blood mononuclear cells of healthy donors. TG silkworm lines expressing a MAGE-A4 gene under an upstream activating sequence (UAS) were mated with those expressing a yeast transcription activator protein (GAL4) at the middle silk glands (MSGs) and embryos that harbored both the GAL4 and UAS constructs were selected. Recombinant MAGE-A4 protein was extracted from the MSGs of TG silkworms and evaluated using SDS-PAGE and western blot analysis. It was observed that MAGE-A4 produced by the TG silkworm system successfully induced MAGE-A4-specific CD4⁺ T cell responses. Furthermore, MAGE-A4-specific CD4⁺ T cells recognized antigen-presenting cells when pulsed with a MAGE-A4⁺ tumor cell lysate. The present data suggests that recombinant tumor antigen production using the TG silkworm system may be a novel tool in the preparation of cancer vaccines.

Current status of cancer immunotherapy for esophageal squamous cell carcinoma

BACKGROUND

Immunotherapy has become a promising treatment strategy for cancer. Immune checkpoint blockade with anti-CTLA4 mAb and anti-PD-1 mAb has demonstrated clear evidence of objective responses including improved overall survival and tumor shrinkage, driving renewed enthusiasm for cancer immunotherapy in multiple cancer types including esophageal squamous cell carcinoma (ESCC). There are several clinical trials using anti-PD1 mAb for ESCC in early phases and the results are currently promising.

RESULTS AND CONCLUSIONS

In this review, recent advances in cancer immunotherapy for ESCC are discussed with particular focus on immune checkpoint inhibitors and cancer vaccine.

MAGEA4 expression in bone and soft tissue tumors: its utility as a target for immunotherapy and diagnostic marker combined with NY-ESO-1

Cancer-testis (CT) antigens have promise as targets for immunotherapy, because of their restricted expression in tumor or testis tissue. MAGEA4 is both a MAGE family member and a CT antigen, and has attracted attention as a potential immunotherapeutic target. We investigated MAGEA4 expression by immunohistochemistry in bone and soft tissue tumor specimens that consisted of 35 malignant or intermediate and 24 benign histological subtypes, in order to evaluate its possible utility as an immunotherapy target and its potential use as a diagnostic marker when combined with another CT antigen, NY-ESO-1. Among these tumors, MAGEA4 was detected in 82.2% of synovial sarcomas, 67.7% of myxoid liposarcomas, 43.8% of osteosarcomas, 41.4% of angiosarcomas, 24.6% of malignant peripheral nerve sheath tumors (MPNSTs), and 21.4% of chondrosarcomas. NY-ESO-1 expression was found in 88.2% of myxoid liposarcomas, 61.1% of synovial sarcomas, 31.3% of osteosarcomas, 21.4% of pleomorphic liposarcomas, 16.7% of desmoplastic small round cell tumors, and 14.3% of chondrosarcomas. Benign tumors and non-tumorous tissue, except for testis tissue, did not express MAGEA4 or NY-ESO-1. Combined use of MAGEA4 and NY-ESO-1 increased the sensitivity, specificity, positive predictive values, and negative predictive values for distinguishing synovial sarcoma from spindle cell tumors and other mimicking tumors, compared to individual use of MAGEA4 or NY-ESO-1. Our results support the immunotherapy targeting MAGEA4 or NY-ESO-1 can be an ancillary therapy in the above-mentioned tumors, and the potential utility of MAGEA4 as an ancillary diagnostic marker for synovial sarcoma combined with NY-ESO-1.

Promising immunotherapies for esophageal cancer

INTRODUCTION

Esophageal cancer (EC) is the eighth most common cancer in the world, and the prognosis of EC is still poor. Although immunotherapy has been developed in melanoma and lung cancer, it is also expected to show efficacy in EC. Currently, several clinical trials are ongoing to evaluate the safety and efficacy of immunotherapies, immune checkpoint inhibitors, adoptive T cell transfer, and therapeutic cancer vaccines in EC. Areas covered: This review provides an overview and the status of immunotherapy in EC. Clinical significance of molecules related immune checkpoints, especially PD-1 and PD-L1 is presented and the designs, results and future directions of clinical trials using immunotherapy in EC are provided. Expert opinion: To bring immunotherapy to the forefront of treatment for EC, it is necessary to select patients who can obtain a high efficacy of immunotherapy and to also elucidate the correct timing for administration. Moreover, combination therapies of immunotherapy with existing chemotherapy or radiation or other immunotherapy with different mechanisms of action must be evaluated to achieve excellent outcomes in patients with EC.

Possible functions of CD169-positive sinus macrophages in lymph nodes in anti-tumor immune responses

The lymph node (LN) is an important immune system in which a number of antigen‐presenting cells are present that induce rapid immune responses to foreign antigens. While a great number of macrophages exist in lymph nodes, recent studies using animal models have shown that lymph node sinus macrophages are associated with the induction of anti‐tumor immunity, playing a significant role in host immune responses against tumor cells. In colorectal tumor, malignant melanoma, and endometrial tumor, it was shown that a high density of CD169‐positive macrophages in the LN sinus was a predictive factor for better clinical prognosis. The observations that the density of CD169‐positive macrophages in the LN sinus was positively associated with the density of infiltrating T or NK cells in tumor tissues, indicates the significance of CD169‐positive macrophages in anti‐tumor immune reactions of tumor patients. Moreover, antigen delivery targeting LN macrophages is also considered to be promising approach for vaccination. In this article, we have summarized the significance of CD169‐positive LN macrophages in anti‐tumor immunity.

Future directions in esophageal cancer therapy

Resection techniques for esophageal carcinoma continue to evolve, from endoscopic mucosal resection or endoscopic submucosal dissection for early stage disease to standard and robot-assisted minimally invasive esophagectomy as part of multimodal therapy for locally advanced disease. Though currently limited to assessing conduit perfusion and sentinel lymph nodes, embedded technology in the robotic surgical platform will likely play an expanded role during esophagectomy in the future. The use of targeted therapies, checkpoint inhibitors, engineered immune cell therapy, and cancer vaccines show promise in the treatment of systemic disease. Radiation therapy techniques are becoming increasingly sophisticated and they may play a more active role in stage IV disease in the future.

Translational nanoparticle engineering for cancer vaccines

Conventional cancer treatments remain insufficient to treat many therapy-resistant tumors.¹ Cancer vaccines attempt to overcome this resistance by activating the patient's immune system to eliminate tumor cells without the toxicity of systemic chemotherapy and radiation. Nanoparticles (NPs) are promising as customizable, immunostimulatory carriers to protect and deliver antigen. Although many NP vaccines have been investigated in preclinical settings, a few have advanced into clinical application, and still fewer have demonstrated clinical benefit. This review incorporates observations from NP vaccines that have been evaluated in early phase clinical trials to make recommendations for the next generation of NP-based cancer vaccines.

Immunotherapy for esophageal cancer: Current studies and future perspectives

Esophageal cancer is one of the most common malignant tumors of the digestive system, and China has the highest morbidity and mortality rates of esophageal cancer in the world. Currently, main therapies for esophageal cancer include endoscopy, surgery, chemotherapy, and radiotherapy. These traditional treatments have appreciated clinical effects, but the prognosis of this malignancy is still poor. There is accumulating evidence that tumor immune microenvironment plays a key role in the development and progression of esophageal cancer. Recent clinical investigations and ongoing studies indicate that immunotherapy might have a great potential in the treatment of patients with esophageal cancer. Future studies will identify treatment strategies that can maximize therapeutic benefits by combining immunotherapies with existing and novel treatment modalities.

Nanogels: An overview of properties, biomedical applications and obstacles to clinical translation

Nanogels have emerged as a versatile hydrophilic platform for encapsulation of guest molecules with a capability to respond to external stimuli that can be used for a multitude of applications. These are soft materials capable of holding small molecular therapeutics, biomacromolecules, and inorganic nanoparticles within their crosslinked networks, which allows them to find applications for therapy as well as imaging of a variety of disease conditions. Their stimuli-responsive behavior can be easily controlled by selection of constituent polymer and crosslinker components to achieve a desired response at the site of action, which imparts nanogels the ability to participate actively in the intended function of the carrier system rather than being passive carriers of their cargo. These properties not only enhance the functionality of the carrier system but also help in overcoming many of the challenges associated with the delivery of cargo molecules, and this review aims to highlight the distinct and unique capabilities of nanogels as carrier systems for the delivery of an array of cargo molecules over other nanomaterials. Despite their obvious usefulness, nanogels are still not a commonplace occurrence in clinical practice. We have also made an attempt to highlight some of the major challenges that need to be overcome to advance nanogels further in the field of biomedical applications.

Biochemical and proteomic characterization of retrovirus Gag based microparticles carrying melanoma antigens

Extracellular vesicles are membraneous particles released by a variety of cells into the extracellular microenvironment. Retroviruses utilize the cellular vesiculation pathway for virus budding/assembly and the retrovirus Gag protein induces the spontaneous formation of microvesicles or virus-like particles (VLPs) when expressed in the mammalian cells. In this study, five different melanoma antigens, MAGEA4, MAGEA10, MART1, TRP1 and MCAM, were incorporated into the VLPs and their localization within the particles was determined. Our data show that the MAGEA4 and MAGEA10 proteins as well as MCAM are expressed on the surface of VLPs. The compartmentalization of exogenously expressed cancer antigens within the VLPs did not depend on the localization of the protein within the cell. Comparison of the protein content of VLPs by LC-MS/MS-based label-free quantitative proteomics showed that VLPs carrying different cancer antigens are very similar to each other, but differ to some extent from VLPs without recombinant antigen. We suggest that retrovirus Gag based virus-like particles carrying recombinant antigens have a potential to be used in cancer immunotherapy.

Clinical relevance of antigen spreading pattern induced by CHP-MAGE-A4 cancer vaccination

AIM

To investigate the antigen spreading pattern in the CHP-MAGE-A4-vaccinated patients and analyze the clinical relevance of antigen spreading pattern as a surrogate marker of patient survival.

MATERIALS & METHODS

12 patients who had been injected with 300 μg of CHP-MAGE-A4 and 0.5 Klinische Einheit of OK-432 in more than five vaccinations were analyzed.

RESULTS

Increases in the anti-MAGE-A4-specific antibody response were observed in eight patients (66.7%), compared with six patients (50%) for anti-NY-ESO-1 and five patients (41.7%) for anti-MAGE-A3 after five vaccinations. We identified frequent antigen spreading following MAGE-A4 vaccinations without associations with the clinical response or patient prognosis.

CONCLUSION

Antigen spreading pattern might reflect tumor shrinkage as a response to treatment and treatment history (clinical trial registration number: UMIN000001999).

Current advances in self-assembled nanogel delivery systems for immunotherapy

Since nanogels (nanometer-sized gels) were developed two decades ago, they were utilized as carriers of innovative drug delivery systems. In particular, immunological drug delivery via self-assembled nanogels (self-nanogels) owing to their nanometer size and molecular chaperon-like ability to encapsulate large biomolecules is one of the most well studied and successful applications of nanogels. In the present review, we focus on self-nanogel applications as immunological drug delivery systems for cancer vaccines, cytokine delivery, nasal vaccines, and nucleic acid delivery, including several clinical trials. Cancer vaccines were the first practical application of self-nanogels as vehicles for drug delivery. After successful pre-clinical studies, phase I clinical trials were conducted, and it was found that vaccines consisting of self-nanogels could be administered repeatedly to humans without serious adverse effects, and self-nanogel vaccines induced antigen-specific cellular and humoral immunity. Cytokine delivery via self-nanogels led to the sustained release of IL-12, suppressed tumor growth, and increased Th1-type immune responses. Cationic self-nanogels were effective in penetrating the nasal mucosa and resulted in successful nasal vaccines in mice and nonhuman primates. Cationic self-nanogels were also used for the intracellular delivery of proteins and nucleic acids, and were successfully used to knockdown tumor growth factor expression using short interfering RNA with the immunological effect. These studies suggest that self-nanogels are currently one of the most unique and attractive immunological drug delivery systems and are edging closer to practical use.

MAGE-A expression, immune microenvironment, and prognosis in upper urinary tract carcinoma

The melanoma-associated antigen A (MAGE-A) family comprises cancer-testis antigens that represent promising prognostic biomarkers and immunotherapy targets in several cancer types. The aim of this study was to investigate the significance of MAGE-A expression in upper urinary tract urothelial carcinoma in relation to clinicopathological features, lymphocytic infiltration, and clinical outcome. We immunohistochemically examined the expression of MAGE-A in 171 patients with upper urinary tract urothelial carcinoma. High (≥ 50% positive) and low MAGE-A expression levels were observed in 33 (19%) and 49 (29%) cases, respectively. MAGE-A was negative in 89 cases (52%). MAGE-A expression was positively correlated with high histologic grade; concomitant carcinoma in situ; higher Ki-67 proliferation index; and infiltration of CD3-, CD8-, and CD45RO-positive T lymphocytes, but not with CD20-positive B lymphocytes. High MAGE-A expression was significantly associated with shorter metastasis-free survival after nephroureterectomy (log-rank P = .019; multivariate hazard ratio, 1.98; 95% confidence interval, 1.00-3.92). MAGE-A expression in metastatic lymph nodes was highly correlated with its expression in primary lesions. MAGE-A expression was retained in chemotherapy-resistant metachronous metastatic lesions of urothelial carcinoma. MAGE-A may be a promising prognostic biomarker and potential immunotherapeutic target for patients with upper urinary tract urothelial carcinoma.