Immune Therapy Resistance and Immune Escape of Tumors

SIRT7 promotes mitochondrial biogenesis to render the adaptive resistance to MAPK inhibition in melanoma

Melanoma, arising from the malignant transformation of melanocytes, stands as the most lethal type of skin cancer. While significant strides have been made in targeted therapy and immunotherapy, substantially enhancing therapeutic efficacy, the prognosis for melanoma patients remains unoptimistic. SIRT7, a nuclear-localized deacetylase, plays a pivotal role in maintaining cellular homeostasis and adapting to external stressors in melanoma, with its activity closely tied to intracellular nicotinamide adenine dinucleotide (NAD+). However, its involvement in adaptive resistance to targeted therapy remains unclear. Herein, we unveil that up-regulated SIRT7 promotes mitochondrial biogenesis to render the adaptive resistance to MAPK inhibition in melanoma. Initially, we observed a significant increase of SIRT7 expression in publicly available datasets following targeted therapy within a short duration. In consistent, we found elevated SIRT7 expression in melanoma cells subjected to BRAF or MEK inhibitors in vitro. The up-regulation of SIRT7 expression was also confirmed in xenograft tumors in mice after targeted therapy in vivo. Furthermore, we proved that SIRT7 deficiency led to decreased cell viability upon prolonged exposure to BRAF or MEK inhibitors, accompanied by an increase in cell apoptosis. Mechanistically, SIRT7 deficiency restrained the upregulation of genes associated with mitochondrial biogenesis and intracellular ATP levels in response to targeted therapy treatment in melanoma cells. Ultimately, we proved that SIRT7 deficieny could sensitize BRAF-mutant melanoma cells to MAPK inhibition targeted therapy in vivo. In conclusion, our findings underscore the role of SIRT7 in fostering adaptive resistance to targeted therapy through the facilitation of mitochondrial biogenesis. Targeting SIRT7 emerges as a promising strategy to overcome MAPK inhibitor adaptive resistance in melanoma.

Small-molecule agents for cancer immunotherapy

Cancer immunotherapy, exemplified by the remarkable clinical benefits of the immune checkpoint blockade and chimeric antigen receptor T-cell therapy, is revolutionizing cancer therapy. They induce long-term tumor regression and overall survival benefit in many types of cancer. With the advances in our knowledge about the tumor immune microenvironment, remarkable progress has been made in the development of small-molecule drugs for immunotherapy. Small molecules targeting PRR-associated pathways, immune checkpoints, oncogenic signaling, metabolic pathways, cytokine/chemokine signaling, and immune-related kinases have been extensively investigated. Monotherapy of small-molecule immunotherapeutic drugs and their combinations with other antitumor modalities are under active clinical investigations to overcome immune tolerance and circumvent immune checkpoint inhibitor resistance. Here, we review the latest development of small-molecule agents for cancer immunotherapy by targeting defined pathways and highlighting their progress in recent clinical investigations.

Supramolecular prodrug-like nanotheranostics with dynamic and activatable nature for synergistic photothermal immunotherapy of metastatic cancer

Synergistic photothermal immunotherapy has attracted widespread attention due to the mutually reinforcing therapeutic effects on primary and metastatic tumors. However, the lack of clinical approval nanomedicines for spatial, temporal, and dosage control of drug co-administration underscores the challenges facing this field. Here, a photothermal agent (Cy7-TCF) and an immune checkpoint blocker (NLG919) are conjugated via disulfide bond to construct a tumor-specific small molecule prodrug (Cy7-TCF-SS-NLG), which self-assembles into prodrug-like nano-assemblies (PNAs) that are self-delivering and self-formulating. In tumor cells, over-produced GSH cleaves disulfide bonds to release Cy7-TCF-OH, which re-assembles into nanoparticles to enhance photothermal conversion while generate reactive oxygen species (ROSs) upon laser irradiation, and then binds to endogenous albumin to activate near-infrared fluorescence, enabling multimodal imaging-guided phototherapy for primary tumor ablation and subsequent release of tumor-associated antigens (TAAs). These TAAs, in combination with the co-released NLG919, effectively activated effector T cells and suppressed Tregs, thereby boosting antitumor immunity to prevent tumor metastasis. This work provides a simple yet effective strategy that integrates the supramolecular dynamics and reversibility with stimuli-responsive covalent bonding to design a simple small molecule with synergistic multimodal imaging-guided phototherapy and immunotherapy cascades for cancer treatment with high clinical value.

Self-heating mitochondrion-induced free radical blast for immunogenic cell death stimulation and HCC immunotherapy

Hepatocellular carcinoma (HCC) is an immunosuppressive tumor associated with high mortality. Photothermal and photodynamic therapies have been applied to induce immunogenic cell death (ICD) in HCC, successfully eliciting immune responses but facing limitations in penetration depth in clinical trials. Here, intrinsic mitochondrial hyperthermia was used to trigger thermosensitive drug release. The mitochondria were further self-heated through 2,4-dinitrophenol uncoupling, dramatically promoting free radical initiation and inducing tumor ICD. The synthesized mitochondrial-targeting TPP-HA-TDV nanoparticles specifically generated free radicals in the mitochondria without external stimulation, and obviously enhanced the release of ICD markers, subsequently evoking immune responses. The results showed that mitochondrial hyperthermia could be an endogenous target for thermosensitive drug release. Furthermore, self-heating mitochondria-induced free radical blast could be an efficient therapeutic for deep-seated tumor therapy.

Emerging Therapeutic Targets and Drug Resistance Mechanisms in Immunotherapy of Hematological Malignancies

CAR-T cell therapy has revolutionized the treatment of hematological malignancies with high remission rates in the case of ALL and NHL. This therapy has some limitations such as long manufacturing periods, persistent restricted cell sources and high costs. Moreover, combination regimens increase the risk of immune-related adverse events, so the identification new therapeutic targets is important to minimize the risk of toxicities and to guide more effective approaches. Cancer cells employ several mechanisms to evade immunosurveillance, which causes resistance to immunotherapy; therefore, a very important therapeutic approach is to focus on the development of rational combinations of targeted therapies with non-overlapping toxicities. Recent progress in the development of new inhibitory clusters of differentiation (CDs), signaling pathway molecules, checkpoint inhibitors, and immunosuppressive cell subsets and factors in the tumor microenvironment (TME) has significantly improved anticancer responses. Novel strategies regarding combination immunotherapies with CAR-T cells are the most promising approach to cure cancer.

A novel immunogenic cell death-related genes signature for predicting prognosis, immune landscape and immunotherapy effect in hepatocellular carcinoma

OBJECTIVE

Immunogenic cell death (ICD) has emerged as a promising strategy to activate the adaptive immune response, modulate the tumor microenvironment (TME) and enhance the efficacy of immune therapy. However, the relationship between ICD and TME reprogramming in hepatocellular carcinoma (HCC) remains poorly understood.

METHODS

Transcriptional profiles and clinical spectrum of 486 HCC patients were obtained from TCGA and GEO databases. We utilized consensus clustering analysis to construct two distinct molecular subtypes and established an ICD-based scoring system (named ICD score) via WGCNA and LASSO Cox regression to predict the prognosis of the HCC cohort. Then we employed CIBERSORT and ESTIMATE methods to analyze the immune landscape of ICD score in HCC. Subsequently, the immunophenoscore (IPS) and tumor immune dysfunction and rejection (TIDE) analyses were performed to determine whether the ICD score could influence the immune therapeutic effect. Based on the ICD scoring system, a novel nomogram was generated to provide a numerical probability of HCC patients' overall survival (OS).

RESULTS

We identified two independent ICD clusters (cluster A/B), and cluster B possessed a worse prognosis and higher immune cell infiltration. Using ICD scoring system, the HCC patients were divided into high- and low-ICD-score groups. Through integrative analyses, the high-ICD cohort owned advanced TNM stage, high pathologic grade and increased suppressive immune cell enrichment. We developed a nomogram containing the ICD score, demonstrating a high predictive accuracy with a C-index of 0.703. We further discovered that PSMD2 and PSMD14 could serve as ICD-associated prognostic biomarkers and therapeutic targets in HCC.

CONCLUSION

The ICD score exhibits a high degree of reliability for predicting prognosis and may provide valuable guidance for the selection of immunotherapy for HCC patients. This novel scoring system enables the estimation of clinical immunotherapy response for HCC patients, offering new opportunities for personalized immunotherapy.

Therapeutic application of manganese-based nanosystems in cancer radiotherapy

Radiotherapy is an important therapeutic modality in the treatment of cancers. Nevertheless, the characteristics of the tumor microenvironment (TME), such as hypoxia and high glutathione (GSH), limit the efficacy of radiotherapy. Manganese-based (Mn-based) nanomaterials offer a promising prospect for sensitizing radiotherapy due to their good responsiveness to the TME. In this review, we focus on the mechanisms of radiosensitization of Mn-based nanosystems, including alleviating tumor hypoxia, increasing reactive oxygen species production, increasing GSH conversion, and promoting antitumor immunity. We further illustrate the applications of these mechanisms in cancer radiotherapy, including the development and delivery of radiosensitizers, as well as their combination with other therapeutic modalities. Finally, we summarize the application of Mn-based nanosystems as contrast agents in realizing precision therapy. Hopefully, the present review will provide new insights into the biological mechanisms of Mn-based nanosystems, as well as their applications in radiotherapy, in order to address the difficulties and challenges that remain in their clinical application in the future.

Integrated Clinical, Molecular and Immunological Characterization of Pulmonary Sarcomatoid Carcinomas Reveals an Immune Escape Mechanism That May Influence Therapeutic Strategies

Pulmonary sarcomatoid carcinoma (PSC) has highly aggressive biological behaviour and poor clinical outcomes, raising expectations for new therapeutic strategies. We characterized 179 PSC by immunohistochemistry, next-generation sequencing and in silico analysis using a deep learning algorithm with respect to clinical, immunological and molecular features. PSC was more common in men, older ages and smokers. Surgery was an independent factor (p < 0.01) of overall survival (OS). PD-L1 expression was detected in 82.1% of all patients. PSC patients displaying altered epitopes due to processing mutations showed another PD-L1-independent immune escape mechanism, which also significantly influenced OS (p < 0.02). The effect was also maintained when only advanced tumour stages were considered (p < 0.01). These patients also showed improved survival with a significant correlation for immunotherapy (p < 0.05) when few or no processing mutations were detected, although this should be interpreted with caution due to the small number of patients studied. Genomic alterations for which there are already approved drugs were present in 35.4% of patients. Met exon 14 skipping was found more frequently (13.7%) and EGFR mutations less frequently (1.7%) than in other NSCLC. In summary, in addition to the divergent genomic landscape of PSC, the specific immunological features of this prognostically poor subtype should be considered in therapy stratification.

PD-1/PD-L1 immune checkpoint inhibitors in metastatic triple-negative breast cancer: a systematic review and meta-analysis

Background

PD-1/PD-L1 immune checkpoint inhibitors (ICIs) have been controversial in the treatment of metastatic triple negative breast cancer (mTNBC). We collected randomized controlled trials in accordance with the study and carried out meta-analysis to comprehensively evaluate the efficacy and safety of immune checkpoint inhibitors in mTNBC.

Aim

To systematically evaluate the efficacy and safety of PD-1/PD-L1 ICIs (hereinafter referred to as ICIs) in the treatment of mTNBC.

Methods

As of 2023.2.5, Medline, PubMed, Embase, Cochrane library database and Web of Science were searched to determine the study in accordance with the trial of ICIs in the treatment of mTNBC. The assessment endpoints included objective response rate (ORR), progression-free survival (PFS), overall survival (OS), and safety. Meta-analysis of the included studies was performed using Revman 5.4.

Results

A total of six trials with 3172 patients were included in this meta-analysis. The ORR of ICIs combined with chemotherapy was significantly improved compared with chemotherapy (HR=0.88, 95%CI: 0.81-0.94, I² = 0%). For PFS, the experimental group were better than the control group in both intention-to-treat (ITT) population and PD-L1 positive population, showing statistical significance (ITT: HR=0.81, 95%CI: 0.74-0.89, P<0.05, I² = 0%; PD-L1 positive: HR=0.72, 95%CI: 0.63-0.82, P<0.05, I² = 18%); For OS, in the ITT population, no statistical difference was observed in either ICIs combined with chemotherapy(HR=0.92, 95%CI: 0.83-1.02, P=0.10)or immune monotherapy(HR=0.78, 95%CI: 0.44-1.36, P=0.37), in the PD-L1 positive population, ICIs group had better OS than chemotherapy group (HR=0.83, 95%CI: 0.74-0.93, P < 0.05); In safety, serious adverse event (SAE) was no statistically significant difference between the ICIs group and the chemotherapy group; however, the incidence of immune-related adverse event (irAE) was significantly higher in the ICIs group than in the chemotherapy group (HR=2.15, 95%CI: 1.45-3.19, P < 0.05).

Conclusion

ICIs combined with chemotherapy significantly improved the PFS of mTNBC, however, ICIs only improved the OS in PD-L1 positive people, and no statistical difference was observed in ITT population; while benefiting from ICIs, we found that irAE in ICIs group increased significantly, and its high rate of adverse events still needs to be taken seriously.

Inflammatory biomarkers as predictors of immune activation to different irradiated sites and short-term efficacy in advanced squamous cell esophageal carcinoma received radioimmunotherapy

Purpose

The present study aimed to compare immune activation among different irradiated sites and identify potential short-term efficacy prognostic factors in patients with advanced squamous cell esophageal carcinoma (ESCC) who received radiotherapy (RT) and immunotherapy.

Patients and methods

We recorded the clinical characteristics, blood cell counts, and derived blood index ratios, including neutrophil-to-lymphocyte ratio (NLR), lymphocyte-to-monocyte ratio (LMR), platelet-to-lymphocyte ratio (PLR), and systemic immune-inflammation index (SII), at three time points (before, during, and after RT) in 121 patients with advanced ESCC who had received RT and immunotherapy. Chi-square test and univariate and multivariate logistic regression analyses were used to calculate the relationships among inflammatory biomarkers (IBs), irradiated sites, and short-term efficacy.

Results

Delta-IBs were calculated as (medio-IBs - pre-IBs) ÷ pre-IBs. The medians of delta-LMR, and delta-ALC were the highest, whereas the median of delta-SII was the lowest in patients with brain radiation. Treatment responses were observed within 3 months after RT or until the beginning of the next line therapy, and the disease control rate (DCR) was 75.2%. The areas under the receiver operating characteristic curve (AUCs) for delta-NLR and delta-SII were 0.723 (p = 0.001) and 0.725 (p < 0.001), respectively. Multivariate logistic regression analysis showed that the treatment lines of immunotherapy (odds ratio [OR], 4.852; 95% confidence interval [CI], 1.595-14.759; p = 0.005) and delta-SII (OR, 5.252; 95% CI, 1.048-26.320; p = 0.044) were independent indicators of short-term efficacy.

Conclusion

In this study, we found that RT to the brain had a stronger immune activation effect than RT to extracranial organs. We also found that earlier-line immunotherapy plus RT and a decrease in SII during RT may generate better short-term efficacy in advanced ESCC.

Inside PD-1/PD-L1,2 with their inhibitors

This review summarizes current knowledge in the development of immune checkpoint inhibitors, including antibodies and small molecules.

Interrelation between Programmed Cell Death and Immunogenic Cell Death: Take Antitumor Nanodrug as an Example

Programmed cell death (PCD, mainly including apoptosis, necrosis, ferroptosis, pyroptosis, and autophagy) and immunogenic cell death (ICD), as important cell death mechanisms, are widely reported in cancer therapy, and understanding the relationship between the two is significant for clinical tumor treatments. Considering that vast nanodrugs are developed to induce tumor PCD and ICD simultaneously, in this review, the interrelationship between PCD and ICD is described using nanomedicines as examples. First, an overview of PCD patterns and focus on the morphological differences and interconnections among them are provided. Then the interrelationship between apoptosis and ICD in terms of endoplasmic reticulum stress is described by introducing various cancer treatments and the recent developments of nanomedicines with inducible immunogenicity. Next, the crosstalk between non-apoptotic (including necrosis, ferroptosis, pyroptosis, and autophagy) signaling pathways and ICD is introduced and their relationship through various nanomedicines as examples is further illustrated. Finally, the relationship between PCD and ICD and its application prospects in the development of new ICD nanomaterials are summarized. This review is believed to deepen the understanding of the relationship between PCD and ICD, extend the biomedical applications of various nanodrugs, and promote the progress of clinical tumor therapy.

The peptide woods are lovely, dark and deep: Hunting for novel cancer antigens

Harnessing the patient's immune system to control a tumor is a proven avenue for cancer therapy. T cell therapies as well as therapeutic vaccines, which target specific antigens of interest, are being explored as treatments in conjunction with immune checkpoint blockade. For these therapies, selecting the best suited antigens is crucial. Most of the focus has thus far been on neoantigens that arise from tumor-specific somatic mutations. Although there is clear evidence that T-cell responses against mutated neoantigens are protective, the large majority of these mutations are not immunogenic. In addition, most somatic mutations are unique to each individual patient and their targeting requires the development of individualized approaches. Therefore, novel antigen types are needed to broaden the scope of such treatments. We review high throughput approaches for discovering novel tumor antigens and some of the key challenges associated with their detection, and discuss considerations when selecting tumor antigens to target in the clinic.

Autoreactivity against Denatured Type III Collagen Is Significantly Decreased in Serum from Patients with Cancer Compared to Healthy Controls

Autoantibodies have the potential as cancer biomarkers as they may associate with the outcome and immune-related adverse events (irAEs) following immunotherapy. Cancer and other fibroinflammatory diseases, such as rheumatoid arthritis (RA), are associated with excessive collagen turnover leading to collagen triple helix unfolding and denaturation with exposure of immunodominant epitopes. In this study, we aimed to investigate the role of autoreactivity against denatured collagen in cancer. A technically robust assay to quantify autoantibodies against denatured type III collagen products (anti-dCol3) was developed and then measured in pretreatment serum from 223 cancer patients and 33 age-matched controls. Moreover, the association between anti-dCol3 levels and type III collagen degradation (C3M) and formation (PRO-C3) was investigated. Anti-dCol3 levels were significantly lower in patients with bladder (p = 0.0007), breast (p = 0.0002), colorectal (p < 0.0001), head and neck (p = 0.0005), kidney (p = 0.005), liver (p = 0.030), lung (p = 0.0004), melanoma (p < 0.0001), ovarian (p < 0.0001), pancreatic (p < 0.0001), prostate (p < 0.0001), and stomach cancers (p < 0.0001) compared to controls. High anti-dCol3 levels were associated with type III collagen degradation (C3M, p = 0.0002) but not type III collagen formation (PRO-C3, p = 0.26). Cancer patients with different solid tumor types have downregulated levels of circulating autoantibodies against denatured type III collagen compared to controls, suggesting that autoreactivity against unhealthy type III collagen may be important for tumor control and eradication. This autoimmunity biomarker may have the potential for studying the close relationship between autoimmunity and cancer.

Ciclopirox olamine sensitizes leukemia cells to natural killer cell-mediated cytolysis by upregulating NKG2DLs via the Akt signaling pathway

The activating receptor natural killer group 2D (NKG2D) expressed by Natural killer (NK) cells functions as a "master-switch" in governing the awakening status of NK cells. The NKG2D-mediated cytotoxicity has been declared to be related with the expression levels of NKG2D ligands (NKG2DLs) expressed on tumor cells. Therefore, selective induction of NKG2DLs could be a reliable approach to enhance the efficacy of NK cell-mediated immunotherapy. Our existing study demonstrated that Ciclopirox Olamine (CPX), an off-patent antifungal agent, effectively elevated the expression of NKG2DLs on leukemia cells and sensitized leukemia cells to NK-cell mediated cytolysis. Induction of ROS production and AKT phosphorylation by CPX is essential for the up-regulation of NKG2DLs expressions. Inhibition of AKT by using AKT inhibitor MK2206 decreased both NKG2DLs expressions and NK cell cytotoxicity. These data indicated that increased sensitivity of CPX-treated leukemia cells to NK cell cytolysis was attributed to higher NKG2DLs expressions, resulting from activated AKT signaling pathway. Our findings support the ongoing development of CPX as an anti-tumor agent and suggest its promising immunotherapeutic value in the medication of leukemia.

Precision Killing of M2 Macrophages with Phage-Displayed Peptide-Photosensitizer Conjugates

Among the immunosuppressive cells recruited to the tumor microenvironment, macrophages are particularly abundant and involved in angiogenesis, metastasis, and resistance to current cancer therapies. A strategy that simultaneously targets tumor cells and macrophages, particularly pro-tumoral M2 macrophages, would have significant clinical impact for various types of solid malignancies. By the use of phage display technology, we have recently developed a synthetic peptide, named NW, which binds to M1 and M2 macrophages with high affinity. Additional affinity selection on M2 macrophages identified only dominant peptides whose binding motifs are similar to that of the NW peptide. To reduce the frequency of selecting such dominating peptides, the peptide library was affinity selected on M2 macrophages blocked with NW peptide. This approach resulted in the selection of peptides that bind to M2, but not M1 macrophages. To explore the therapeutic potential of the selected peptides, the M13 phage-displayed peptides were conjugated to the photosensitizer IR700, which has been used for cancer photoimmunotherapy. The phage displaying a dominant peptide (SPILWLNAPPWA) killed both M1 and M2 macrophages, while those displaying the M2-specific peptides killed M2 macrophages only upon near-infrared light exposure. A significant fraction of the M2 macrophages were also killed with the untargeted M13 phage-IR700 conjugates. Hence, M2 macrophages can also be selectively targeted by the wild type M13 phage, which displayed a significant tropism to these cells. The benefits of this photoimmunotherapy include an automatic self-targeting ability of the wild type M13 phage, and the option of genetic manipulation of the phage genome to include tumor targeting peptides, allowing the killing of both M2 macrophages and cancer cells.

Immunogenic cell death inducer peptides: A new approach for cancer therapy, current status and future perspectives

Immunogenic Cell Death (ICD) is a type of cell death that kills tumor cells by stimulating the adaptive immune response against other tumor cells. ICD depends on the endoplasmic reticulum (ER) stress and the secretion of Damage-Associated Molecular Patterns (DAMP) by the dying tumor cell. DAMPs recruit innate immune cells such as Dendritic Cells (DC), triggering a cancer-specific immune response such as cytotoxic T lymphocytes (CTLs) to eliminate remaining cancer cells. ICD is accompanied by several hallmarks in dying cells, such as surface translocation of ER chaperones, calreticulin (CALR), and extracellular secretion of DAMPs such as high mobility group protein B1 (HMGB1) and adenosine triphosphate (ATP). Therapeutic peptides can kill bacteria and tumor cells thus affecting the immune system. They have high specificity and affinity for their targets, small size, appropriate cell membrane penetration, short half-life, and simple production processes. Peptides are interesting agents for immunomodulation since they may overcome the limitations of other therapeutics. Thus, the development of peptides affecting the TME and active antitumoral immunity has been actively pursued. On the other hand, several peptides have been recently identified to trigger ICD and anti-cancer responses. In the present review, we review previous studies on peptide-induced ICD, their mechanism, their targets, and markers. They include anti-microbial peptides (AMPs), cationic or mitochondrial targeting, checkpoint inhibitors, antiapoptotic inhibitors, and "don't eat me" inhibitor peptides. Also, peptides will be investigated potentially inducing ICD that is divided into ER stressors, ATPase inhibitors, and anti-microbial peptides.

Immune-regulating camouflaged nanoplatforms: A promising strategy to improve cancer nano-immunotherapy

Although nano-immunotherapy has advanced dramatically in recent times, there remain two significant hurdles related to immune systems in cancer treatment, such as (namely) inevitable immune elimination of nanoplatforms and severely immunosuppressive microenvironment with low immunogenicity, hampering the performance of nanomedicines. To address these issues, several immune-regulating camouflaged nanocomposites have emerged as prevailing strategies due to their unique characteristics and specific functionalities. In this review, we emphasize the composition, performances, and mechanisms of various immune-regulating camouflaged nanoplatforms, including polymer-coated, cell membrane-camouflaged, and exosome-based nanoplatforms to evade the immune clearance of nanoplatforms or upregulate the immune function against the tumor. Further, we discuss the applications of these immune-regulating camouflaged nanoplatforms in directly boosting cancer immunotherapy and some immunogenic cell death-inducing immunotherapeutic modalities, such as chemotherapy, photothermal therapy, and reactive oxygen species-mediated immunotherapies, highlighting the current progress and recent advancements. Finally, we conclude the article with interesting perspectives, suggesting future tendencies of these innovative camouflaged constructs towards their translation pipeline.

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Various immune-regulating camouflaged nanoplatforms are emphasized.

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Immunotherapeutic applications of camouflaged nanoplatforms are systematically summarized.

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ICD-induced therapeutic modalities based on these nanoplatforms are discussed.

Chemo-immunoablation of solid tumors: A new concept in tumor ablation

Chemical ablation was designed to inject chemical agents directly into solid tumors to kill cells and is currently only used clinically for the palliative treatment of tumors. The application and combination of different drugs, from anhydrous ethanol, and glacial acetic acid to epi-amycin, have been clinically tested for a long time. The effectiveness is unsatisfactory due to chemical agents' poor diffusion and concentration. Immunotherapy is considered a prospective oncologic therapeutic. Still, the clinical applications were limited by the low response rate of patients to immune drugs and the immune-related adverse effects caused by high doses. The advent of intratumoral immunotherapy has well addressed these issues. However, the efficacy of intratumoral immunotherapy alone is uncertain, as suggested by the results of preclinical and clinical studies. In this study, we will focus on the research of immunosuppressive tumor microenvironment with chemoablation and intratumoral immunotherapy, the synergistic effect between chemotherapeutic drugs and immunotherapy. We propose a new concept of intratumoral chemo-immunoablation. The concept opens a new perspective for tumor treatment from direct killing of tumor cells while, enhancing systemic anti-tumor immune response, and significantly reducing adverse effects of drugs.

EIF4A3 serves as a prognostic and immunosuppressive microenvironment factor and inhibits cell apoptosis in bladder cancer

EIF4A3 (Eukaryotic translation initiation factor 4A3 (EIF4A3) was recently recognized as an oncogene; however, its role in BLCA (bladder cancer) remains unclear. We explored EIF4A3 expression and its prognostic value in BLCA in public datasets, including the TCGA (The Cancer Genome Atlas) and GEO (Gene Expression Omnibus). Thereafter, the association between EIF4A3 expression and the infiltration of immune cells and immune-checkpoint expression was determined using TIMER2 (Tumor Immune Estimation Resource 2) tool. Additionally, the impact of EIF4A3 on cellular proliferation and apoptosis events in BLCA cell lines was determined by siRNA technology. In this study, EIF4A3 was found to be significantly upregulated in BLCA, upregulated expression of EIF4A3 was related to poor prognosis, advanced histologic grade, subtype, pathological stage, white race, and poor primary therapy outcome. The immune infiltration analysis revealed that EIF4A3 expression was negatively associated with CD8⁺ and CD4⁺ T cells and positively with myeloid-derived suppressor cells, macrophage M2, cancer-associated fibroblasts, and Treg cells. Moreover, EIF4A3 was coexpressed with PD-L1 (programmed cell death 1-ligand 1) and its expression was higher in patients responding to anti-PD-L1 therapy. EIF4A3 knockdown significantly inhibited proliferation and promoted apoptosis in 5,637 and T24 cells. In summary, BLCA patients with elevated EIF4A3 expression had an unfavorable prognosis and immunosuppressive microenvironment, and EIF4A3 may facilitate BLCA progression by promoting cell proliferation and inhibiting apoptosis. Furthermore, our study suggests that EIF4A3 is a potential biomarker and therapeutic target for BLCA.

Immune subtype identification and multi-layer perceptron classifier construction for breast cancer

Introduction

Breast cancer is a heterogeneous tumor. Tumor microenvironment (TME) has an important effect on the proliferation, metastasis, treatment, and prognosis of breast cancer.

Methods

In this study, we calculated the relative proportion of tumor infiltrating immune cells (TIICs) in the breast cancer TME, and used the consensus clustering algorithm to cluster the breast cancer subtypes. We also developed a multi-layer perceptron (MLP) classifier based on a deep learning framework to detect breast cancer subtypes, which 70% of the breast cancer research cohort was used for the model training and 30% for validation.

Results

By performing the K-means clustering algorithm, the research cohort was clustered into two subtypes. The Kaplan-Meier survival estimate analysis showed significant differences in the overall survival (OS) between the two identified subtypes. Estimating the difference in the relative proportion of TIICs showed that the two subtypes had significant differences in multiple immune cells, such as CD8, CD4, and regulatory T cells. Further, the expression level of immune checkpoint molecules (PDL1, CTLA4, LAG3, TIGIT, CD27, IDO1, ICOS) and tumor mutational burden (TMB) also showed significant differences between the two subtypes, indicating the clinical value of the two subtypes. Finally, we identified a 38-gene signature and developed a multilayer perceptron (MLP) classifier that combined multi-gene signature to identify breast cancer subtypes. The results showed that the classifier had an accuracy rate of 93.56% and can be robustly used for the breast cancer subtype diagnosis.

Conclusion

Identification of breast cancer subtypes based on the immune signature in the tumor microenvironment can assist clinicians to effectively and accurately assess the progression of breast cancer and formulate different treatment strategies for different subtypes.

Spatiotemporal analysis of tumour-infiltrating immune cells in biliary carcinogenesis

BACKGROUND

Intraductal papillary neoplasms (IPN) and biliary epithelial neoplasia (BilIN) are well-defined precursor lesions of biliary tract carcinoma (BTC). The aim of this study was to provide a comprehensive characterisation of the inflammatory microenvironment in BTC precursor lesions.

METHODS

Immunohistochemistry was employed to assess tumour-infiltrating immune cells in tissue samples from patients, for whom precursor lesions were identified alongside invasive BTC. The spatiotemporal evolution of the immune microenvironment during IPN-associated carcinogenesis was comprehensively analysed using triplet sample sets of non-neoplastic epithelium, precursor lesion and invasive BTC. Immune-cell dynamics during IPN- and BilIN-associated carcinogenesis were subsequently compared.

RESULTS

Stromal CD3⁺ (P = 0.002), CD4⁺ (P = 0.007) and CD8⁺ (P < 0.001) T cells, CD20⁺ B cells (P = 0.008), MUM1⁺ plasma cells (P = 0.012) and CD163⁺ M2-like macrophages (P = 0.008) significantly decreased in IPN compared to non-tumorous biliary epithelium. Upon transition from IPN to invasive BTC, stromal CD68⁺ (P = 0.001) and CD163⁺ (P < 0.001) macrophages significantly increased. In contrast, BilIN-driven carcinogenesis was characterised by significant reduction of intraepithelial CD8⁺ T-lymphocytic infiltration from non-tumorous epithelium via BilIN (P = 0.008) to BTC (P = 0.004).

CONCLUSION

IPN and BilIN are immunologically distinct entities that undergo different immune-cell variations during biliary carcinogenesis. Intraepithelial CD8⁺ T-lymphocytic infiltration of biliary tissue decreased already at the IPN-precursor stage, whereas BilIN-associated carcinogenesis showed a slowly progressing reduction towards invasive carcinoma.

LOX and Its Methylation Impact Prognosis of Diseases and Correlate with TAM Infiltration in ESCA

Background

ESCA is one of the digestive tract tumors with a high fatality. It is implicated in an intricate gene regulation process, but the pathogenesis remains ambiguous.

Methods

The study used the packages of Limma from R software to analyze DEGs of ESCA in the GEO database and TCGA database. We employed the DAVID website for enrichment analysis, and the string database constructed the PPI network. Hub genes were identified from ESCA DEGs with Cytoscape MCODE. We evaluated the clinical relevance of LOX expression and its DNA methylation in the cBioPortal database and explored the roles of LOX in ESCA immunity, especially immune cell infiltration levels and immune checkpoint expression, by immunedeconv package of R software.

Conclusions

The overexpression of LOX in ESCA is regulated by DNA hypomethylation; LOX overexpression or LOX hypomethylation can predict a worse prognosis in patients with ESCA. Besides, LOX may be involved in TIME regulation, promoting the infiltration levels and function of TAM. Hence, high LOX expression affected by DNA hypomethylation has an essential role in patients with ESCA, which may become an effective prognostic marker and therapeutic target.

Translation of the 27-gene immuno-oncology test (IO score) to predict outcomes in immune checkpoint inhibitor treated metastatic urothelial cancer patients

BACKGROUND

The IO Score is a 27-gene immuno-oncology (IO) classifier that has previously predicted benefit to immune checkpoint inhibitor (ICI) therapy in triple negative breast cancer (TNBC) and non-small cell lung cancer (NSCLC). It generates both a continuous score and a binary result using a defined threshold that is conserved between breast and lung. Herein, we aimed to evaluate the IO Score's binary threshold in ICI-naïve TCGA bladder cancer patients (TCGA-BLCA) and assess its clinical utility in metastatic urothelial cancer (mUC) using the IMvigor210 clinical trial treated with the ICI, atezolizumab.

METHODS

We identified a list of tumor immune microenvironment (TIME) related genes expressed across the TCGA breast, lung squamous and lung adenocarcinoma cohorts (TCGA-BRCA, TCGA-LUSQ, and TCGA-LUAD, 939 genes total) and then examined the expression of these 939 genes in TCGA-BLCA, to identify patients as having high inflammatory gene expression. Using this as a test of classification, we assessed the previously established threshold of IO Score. We then evaluated the IO Score with this threshold in the IMvigor210 cohort for its association with overall survival (OS).

RESULTS

In TCGA-BLCA, IO Score positive patients had a strong concordance with high inflammatory gene expression (p < 0.0001). Given this concordance, we applied the IO Score to the ICI treated IMvigor210 patients. IO Score positive patients (40%) had a significant Cox proportional hazard ratio (HR) of 0.59 (95% CI 0.45-0.78 p < 0.001) for OS and improved median OS (15.6 versus 7.5 months) compared to IO Score negative patients. The IO Score remained significant in bivariate models combined with all other clinical factors and biomarkers, including PD-L1 protein expression and tumor mutational burden.

CONCLUSION

The IMvigor210 results demonstrate the potential for the IO Score as a clinically useful biomarker in mUC. As this is the third tumor type assessed using the same algorithm and threshold, the IO Score may be a promising candidate as a tissue agnostic marker of ICI clinical benefit. The concordance between IO Score and inflammatory gene expression suggests that the classifier is capturing common features of the TIME across cancer types.

Comprehensive analysis of the relationship between the ferroptosis and tumor-infiltrating immune cells, mutation, and immunotherapy in breast cancer

Background

Ferroptosis is a kind of programmed cell death that is characterized by iron dependence. It differs from apoptosis, necrosis, autophagy, pyroptosis, and other types of cell death. Some studies have found that most of the genes involved in the regulation of ferroptosis or act as markers of ferroptosis are related to the poor prognosis of cancer patients.

Methods

This study evaluated the expression, mutation, and copy number variation (CNV) of 60 previously reported ferroptosis genes in breast cancer samples from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. Unsupervised clustering of breast cancer samples with ferroptosis genes was performed, followed by enrichment analysis with Gene Set Variation Analysis (GSVA), mutation display, and correlation analysis of clinical characteristics. Based on the analysis of differences among groups, the ferroptosis-related genes were identified, and the consistent clustering of breast cancer samples was performed. The characteristic genes were screened by stochastic forest algorithm and COX analysis, and a ferroptosis score (ferr.score) model was constructed to evaluate the prognosis of breast cancer patients.

Results

Copy number amplification and deletion of ferroptosis genes are common in breast cancer. Breast cancer patients grouped by ferroptosis gene clusters showed significant differences in survival, immune cell infiltration, and enriched Kyoto Encyclopedia of Genes and Genomes (KEGG) signaling pathways. The ferroptosis-related differential genes were identified by comparison among clustering groups of ferroptosis gene. Characteristic genes were screened from these ferroptosis-related differential genes to construct the ferr.score model. The scoring model could accurately distinguish and predict the survival prognosis and immunotherapy efficacy in breast cancer patients.

Conclusions

Ferroptosis plays an important role in the occurrence and development of tumors. According to the ferr.score model, the breast cancer samples can be divided into two groups with significantly different prognoses. These results provide novel insights and ideas for immunotherapy in breast cancer patients.

Extracellular vesicles in pancreatic cancer immune escape: Emerging roles and mechanisms

Pancreatic cancer (PC) is the most lethal malignancy worldwide due to its delayed diagnosis and limited treatment options. Despite great progress in clinical trials of immunotherapies for various cancers, their effectiveness in PC is very low, indicating that immune evasion is still a major obstacle to immunotherapy in PC. However, the mechanism of immune escape in PC is not fully understood, which substantially restricts the development of immunotherapy. As an important component of intercellular communication networks, extracellular vesicles (EVs) have attracted increasing attention in relation to immune escape. This review aims to provide a better understanding of the roles of EVs in tumor immune escape and the potential to expand their application in cancer immunotherapy. The relationship between PC and the tumor immune microenvironment is briefly introduced. Then, the mechanism by which EVs are involved in immune regulation is summarized, and the latest progress in determining the role of EVs in regulating PC immune escape is highlighted.

Combining Radiation- with Immunotherapy in Prostate Cancer: Influence of Radiation on T Cells

Radiation of tumor cells can lead to the selection and outgrowth of tumor escape variants. As radioresistant tumor cells are still sensitive to retargeting of T cells, it appears promising to combine radio- with immunotherapy keeping in mind that the radiation of tumors favors the local conditions for immunotherapy. However, radiation of solid tumors will not only hit the tumor cells but also the infiltrated immune cells. Therefore, we wanted to learn how radiation influences the functionality of T cells with respect to retargeting to tumor cells via a conventional bispecific T cell engager (BiTE) and our previously described modular BiTE format UNImAb. T cells were irradiated between 2 and 50 Gy. Low dose radiation of T cells up to about 20 Gy caused an increased release of the cytokines IL-2, TNF and interferon-γ and an improved capability to kill target cells. Although radiation with 50 Gy strongly reduced the function of the T cells, it did not completely abrogate the functionality of the T cells.

Identification and validation of EMT-immune-related prognostic biomarkers CDKN2A, CMTM8 and ILK in colon cancer

Colon cancer (CC) is a disease with high incidence and mortality rate. The interaction between epithelial-mesenchymal transition (EMT) and immune status has important clinical significance. We aim to identify EMT-immune-related prognostic biomarkers in colon cancer. The GEO2R and GEPIA 2.0 were utilized to calculate the differential expression genes between CC and normal mucosa. Immport, InnateDB and EMTome databases were used to define EMT-immune-related genes. We conducted batch prognostic analysis by TCGA data. The expression patterns were verified by multiple datasets and lab experiments. GEPIA 2.0 and TIMER 2.0 were utilized to analyze the correlation of the hub genes with EMT markers and immune infiltration. GeneMANIA, STRING, and Metascape were used for co-expression and pathway enrichment analysis. Finally, we established a signature by the method of multivariate Cox regression analysis. CDKN2A, CMTM8 and ILK were filtered out as prognostic genes. CDKN2A and CMTM8 were up-regulated, while ILK was down-regulated in CC. CDKN2A was positively correlated with infiltration of macrophages, Th2 cells, Treg cells, and negatively correlated with NK cells. CMTM8 was negatively correlated with CD8+ T cells, dendritic cells, and NK cells. ILK was positively correlated with CD8+ T cells and dendritic cells. Moreover, CDKN2A, CMTM8 and ILK were significantly correlated with EMT markers. The three genes could participate in the TGF-β pathway. The prognosis model established by the three hub genes was an independent prognosis factor, which can better predict the prognosis. CDKN2A, CMTM8 and ILK are promising prognostic biomarkers and may be potential therapeutic targets in colon cancer.

Effects of Wild Yam Root (Dioscorea villosa) Extract on the Gene Expression Profile of Triple-negative Breast Cancer Cells

BACKGROUND/AIM

Wild yam extract [Dioscorea villosa, (WYE)] is consistently lethal at low IC₅₀s across diverse cancer-lines in vitro. Unlike traditional anti-cancer botanicals, WYE contains detergent saponins which reduce oil-water interfacial tensions causing disintegration of lipid membranes and causing cell lysis, creating an interfering variable. Here, we evaluate WYE at sub-lethal concentrations in MDA-MB-231 triple-negative breast cancer (TNBC) cells.

MATERIALS AND METHODS

Quantification of saponins, membrane potential, lytic death and sub-lethal WYE changes in whole transcriptomic (WT) mRNA, miRNAs and biological parameters were evaluated.

RESULTS

WYE caused 346 differentially expressed genes (DEGs) out of 48,226 transcripts tested; where up-regulated DEGS reflect immune stimulation, TNF signaling, COX2, cytokine release and cholesterol/steroid biosynthesis. Down-regulated DEGs reflect losses in cell division cycle (CDC), cyclins (CCN), cyclin-dependent kinases (CDKs), centromere proteins (CENP), kinesin family members (KIFs) and polo-like kinases (PLKs), which were in alignment with biological studies.

CONCLUSION

Sub-lethal concentrations of WYE appear to evoke pro-inflammatory, steroid biosynthetic and cytostatic effects in TNBC cells.

Enzyme-instructed and mitochondria-targeting peptide self-assembly to efficiently induce immunogenic cell death

Immunogenic cell death (ICD) plays a major role in cancer immunotherapy by stimulating specific T cell responses and restoring the antitumor immune system. However, effective type II ICD inducers without biotoxicity are still very limited. Herein, a tentative drug- or photosensitizer-free strategy was developed by employing enzymatic self-assembly of the peptide F-pY-T to induce mitochondrial oxidative stress in cancer cells. Upon dephosphorylation catalyzed by alkaline phosphatase overexpressed on cancer cells, the peptide F-pY-T self-assembled to form nanoparticles, which were subsequently internalized. These affected the morphology of mitochondria and induced serious reactive oxygen species production, causing the ICD characterized by the release of danger-associated molecular patterns (DAMPs). DAMPs enhanced specific immune responses by promoting the maturation of DCs and the intratumoral infiltration of tumor-specific T cells to eradicate tumor cells. The dramatic immunotherapeutic capacity could be enhanced further by combination therapy of F-pY-T and anti-PD-L1 agents without visible biotoxicity in the main organs. Thus, our results revealed an alternative strategy to induce efficient ICD by physically promoting mitochondrial oxidative stress.

Roles of long noncoding RNAs on tumor immune escape by regulating immune cells differentiation and function

A long noncoding RNA (lncRNA) transcript is generally more than 200 nucleotides in length and rarely codes for any protein. Currently, many lncRNAs have been identified among mammalian genomes, and their known functions are associated with various physiological activities or pathological processes. Some lncRNAs are dysregulated in a variety of malignant tumors, while increasing evidence indicates that abnormal expression can contribute to the regulation of immune cells in tumors and to shaping the immune response. More specifically, lncRNAs participate in regulating the differentiation of immune cells, also known as myeloid and lymphoid cells, as well as recruiting various immunosuppressive factors to influence the tumor microenvironment, thereby promoting tumor cell immune escape. However, we still know very little about the specific mechanism of lncRNAs in immune escape of cancer. Nonetheless, although unprecedented achievements have allowed the development of a new generation of anti-tumor immune therapies to be applied in clinical trials, the drug resistance caused by immune escape has become a major clinical challenge. The focus of this review is to describe the relationship among lncRNAs, immune cells, and tumor immune escape, in order to identify novel diagnostic and therapeutic targets in human cancers.