Immune checkpoint inhibitor combinations: Current efforts and important aspects for success

Disentangling Anti-Tumor Response of Immunotherapy Combinations: A Physiologically Based Framework for V937 Oncolytic Virus and Pembrolizumab

Immuno-oncology (IO) is a growing strategy in cancer treatment. Oncolytic viruses (OVs) can selectively infect cancer cells and lead to direct and/or immune-dependent tumor lysis. This approach represents an opportunity to potentiate the efficacy of immune checkpoint inhibitors (ICI), such as pembrolizumab. Currently, there is a lack of comprehensive quantitative models for the aforementioned scenarios. In this work, we developed a mechanistic framework describing viral kinetics, viral dynamics, and tumor response after intratumoral (i.t.) or intravenous (i.v.) administration of V937 alone or in combination with pembrolizumab. The model accounts for tumor shrinkage, in both injected and non-injected lesions, induced by: viral-infected tumor cell death and activated CD8 cells. OV-infected tumor cells enhanced the expansion of CD8 cells, whereas pembrolizumab inhibits their exhaustion by competing with PD-L1 in their binding to PD-1. Circulating viral levels and treatment effects on tumor volume were adequately characterized in all the different scenarios. This mechanistic-based model has been developed by combining top-down and bottom-up approaches and provides individual estimates of viral and ICI responses. The robustness of the model is reflected by the description of the tumor size time profiles in a variety of clinical scenarios. Additionally, this platform allows us to investigate not only the contribution of processes related to the viral kinetics and dynamics on tumor response, but also the influence of its interaction with an ICI. Additionally, the model can be used to explore different scenarios aiming to optimize treatment combinations and support clinical development.

Signaling pathways involved in colorectal cancer: pathogenesis and targeted therapy

Colorectal cancer (CRC) remains one of the leading causes of cancer-related mortality worldwide. Its complexity is influenced by various signal transduction networks that govern cellular proliferation, survival, differentiation, and apoptosis. The pathogenesis of CRC is a testament to the dysregulation of these signaling cascades, which culminates in the malignant transformation of colonic epithelium. This review aims to dissect the foundational signaling mechanisms implicated in CRC, to elucidate the generalized principles underpinning neoplastic evolution and progression. We discuss the molecular hallmarks of CRC, including the genomic, epigenomic and microbial features of CRC to highlight the role of signal transduction in the orchestration of the tumorigenic process. Concurrently, we review the advent of targeted and immune therapies in CRC, assessing their impact on the current clinical landscape. The development of these therapies has been informed by a deepening understanding of oncogenic signaling, leading to the identification of key nodes within these networks that can be exploited pharmacologically. Furthermore, we explore the potential of integrating AI to enhance the precision of therapeutic targeting and patient stratification, emphasizing their role in personalized medicine. In summary, our review captures the dynamic interplay between aberrant signaling in CRC pathogenesis and the concerted efforts to counteract these changes through targeted therapeutic strategies, ultimately aiming to pave the way for improved prognosis and personalized treatment modalities in colorectal cancer.

Circulating tumor cells with increasing aneuploidy predict inferior prognosis and therapeutic resistance in small cell lung cancer

AIMS

Treatment resistance commonly emerges in small cell lung cancer (SCLC), necessitating the development of novel and effective biomarkers to dynamically assess therapeutic efficacy. This study aims to evaluate the clinical utility of aneuploid circulating tumor cells (CTCs) for risk stratification and treatment response monitoring.

METHODS

A total of 126 SCLC patients (two cohorts) from two independent cancer centers were recruited as the study subjects. Blood samples were collected from these patients and aneuploid CTCs were detected. Aneuploid CTC count (ACC) and aneuploid CTC score (ACS), were used to predict progression-free survival (PFS) and overall survival (OS). The performance of the ACC and the ACS was evaluated by calculating the area under the receiver operating characteristic (ROC) curve (AUC).

RESULTS

Compared to ACC, ACS exhibited superior predictive power for PFS and OS in these 126 patients. Moreover, both univariate and multivariate analyses revealed that ACS was an independent prognostic factor. Dynamic ACS changes reflected treatment response, which is more precise than ACC changes. ACS can be used to assess chemotherapy resistance and is more sensitive than radiological examination (with a median lead time of 2.8 months; P < 0.001). When patients had high ACS levels (> 1.115) at baseline, the combination of immunotherapy and chemotherapy resulted in longer PFS (median PFS, 7.7 months; P = 0.007) and OS (median OS, 16.3 months; P = 0.033) than chemotherapy alone (median PFS, 4.9 months; median OS, 13.6 months).

CONCLUSIONS

ACS could be used as a biomarker for risk stratification, treatment response monitoring, and individualized therapeutic intervention in SCLC patients.

Advances in molecular targeted drugs in combination with CAR-T cell therapy for hematologic malignancies

Molecular targeted drugs and chimeric antigen receptor (CAR) T cell therapy represent specific biological treatments that have significantly improved the efficacy of treating hematologic malignancies. However, they face challenges such as drug resistance and recurrence after treatment. Combining molecular targeted drugs and CAR-T cells could regulate immunity, improve tumor microenvironment (TME), promote cell apoptosis, and enhance sensitivity to tumor cell killing. This approach might provide a dual coordinated attack on cancer cells, effectively eliminating minimal residual disease and overcoming therapy resistance. Moreover, molecular targeted drugs can directly or indirectly enhance the anti-tumor effect of CAR-T cells by inducing tumor target antigen expression, reversing CAR-T cell exhaustion, and reducing CAR-T cell associated toxic side effects. Therefore, combining molecular targeted drugs with CAR-T cells is a promising and novel tactic for treating hematologic malignancies. In this review article, we focus on analyzing the mechanism of therapy resistance and its reversal of CAR-T cell therapy resistance, as well as the synergistic mechanism, safety, and future challenges in CAR-T cell therapy in combination with molecular targeted drugs. We aim to explore the benefits of this combination therapy for patients with hematologic malignancies and provide a rationale for subsequent clinical studies.

Enhancing cancer immunotherapy with photodynamic therapy and nanoparticle: making tumor microenvironment hotter to make immunotherapeutic work better

Cancer immunotherapy has made tremendous advancements in treating various malignancies. The biggest hurdle to successful immunotherapy would be the immunosuppressive tumor microenvironment (TME) and low immunogenicity of cancer cells. To make immunotherapy successful, the 'cold' TME must be converted to 'hot' immunostimulatory status to activate residual host immune responses. To this end, the immunosuppressive equilibrium in TME should be broken, and immunogenic cancer cell death ought to be induced to stimulate tumor-killing immune cells appropriately. Photodynamic therapy (PDT) is an efficient way of inducing immunogenic cell death (ICD) of cancer cells and disrupting immune-restrictive tumor tissues. PDT would trigger a chain reaction that would make the TME 'hot' and have ICD-induced tumor antigens presented to immune cells. In principle, the strategic combination of PDT and immunotherapy would synergize to enhance therapeutic outcomes in many intractable tumors. Novel technologies employing nanocarriers were developed to deliver photosensitizers and immunotherapeutic to TME efficiently. New-generation nanomedicines have been developed for PDT immunotherapy in recent years, which will accelerate clinical applications.

Risk of cardiovascular toxicity with combination of immune-checkpoint inhibitors and angiogenesis inhibitors: a meta-analysis

Introduction

Combinations of immune checkpoint inhibitors (ICIs) and angiogenesis inhibitors (AIs) have been investigated for the treatment of several tumor types. Both ICIs and AIs may lead to cardiovascular adverse events, and their combination may potentially increase the risk for cardiovascular toxicity. In the present meta-analysis, we aim to assess the cardiovascular toxicity of ICIs plus AIs vs. AIs alone. Secondary objectives are non-cardiovascular adverse events and efficacy.

Methods

Systematic review was performed according to PRISMA statement. Phase II and III randomized clinical trials were identified by searching the MEDLINE/PubMed, Cochrane Library and ASCO Meeting abstracts, from inception to June 2022. The pooled risks for overall response rate (ORR), 1-year progression-free survival (PFS), adverse events (AEs), immune-related AEs, (irAEs), hypertension, and vascular events defined as stroke, myocardial infarction and pulmonary embolisms, were calculated.

Results

In terms of cardiovascular toxicity, we found higher risk for severe hypertension among patients treated with ICIs plus AIs as compared with those receiving AIs (OR 1.24, 95% CI: 1.01-1.53), but no significant difference was found for any-grade hypertension, and for vascular events. There was also no difference in terms of overall AEs, whereas the incidence of irAEs was increased in the ICIs plus AIs arm, as expected. In terms of efficacy, ICIs plus AIs achieved better ORR (OR 2.25, 95% CI: 1.70-2.97) and PFS (HR 0.49, 95% CI: 0.39-0.63) as compared to AIs alone.

Conclusion

The addition of ICIs to AIs significantly increased the risk of high-grade hypertension, but not that of acute vascular events.

Magnetic Metal-Organic Framework-Based Nanoplatform with Platelet Membrane Coating as a Synergistic Programmed Cell Death Protein 1 Inhibitor against Hepatocellular Carcinoma

Programmed cell death protein 1 (PD-1) inhibitors are the most common immune-checkpoint inhibitors and considered promising drugs for hepatocellular carcinoma (HCC). However, in clinical settings, they have a low objective response rate (15%-20%) for patients with HCC; this is because of the insufficient level and activity of tumor-infiltrating T lymphocytes (TILs). The combined administration of oxymatrine (Om) and astragaloside IV (As) can increase the levels of TILs by inhibiting the activation of cancer-associated fibroblasts (CAFs) and improve the activity of TILs by enhancing their mitochondrial function. In the present study, we constructed a magnetic metal-organic framework (MOF)-based nanoplatform with platelet membrane (Pm) coating (PmMN@Om&As) to simultaneously deliver Om and As into the HCC microenvironment. We observed that PmMN@Om&As exhibited a high total drug-loading capacity (33.77 wt %) and good immune escape. Furthermore, it can target HCC tissues in a magnetic field and exert long-lasting effects. The HCC microenvironment accelerated the disintegration of PmMN@Om&As and the release of Om&As, thereby increasing the level and activity of TILs by regulating CAFs and the mitochondrial function of TILs. In addition, the carrier could synergize with Om&As by enhancing the oxygen consumption rate and proton efflux rate of TILs, thereby upregulating the mitochondrial function of TILs. Combination therapy with PmMN@Om&As and α-PD-1 resulted in a tumor suppression rate of 84.15% and prolonged the survival time of mice. Our study provides a promising approach to improving the antitumor effect of immunotherapy in HCC.

Tumor microenvironment-responsive DNA-based nanomedicine triggers innate sensing for enhanced immunotherapy

Lack of proper innate sensing inside the tumor microenvironment could reduce both innate and adaptive immunity, which remains a critical cause of immunotherapy failure in various tumor treatments. Double-stranded DNA (dsDNA) has been evidenced to be a promising immunostimulatory agent to induce type I interferons (IFN-Is) production for innate immunity activation through the cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) signaling pathway, yet the unsatisfactory delivery and susceptibility to nuclease degradation hindered its feasibility for further clinical applications. Herein, we report on the constructed tumor microenvironment-responsive DNA-based nanomedicine loaded by dendritic mesoporous organosilica nanoparticles (DMONs), which provide efficient delivery of dsDNA to induce intratumoral IFN-Is production for triggering innate sensing for enhanced anti-tumor immunotherapy. Extensive in vitro and in vivo evaluations have demonstrated the dramatic IFN-Is production induced by dsDNA@DMONs in both immune cells and tumor cells, which facilitates dendritic cells (DCs) maturation and T cells activation for eliciting the potent innate immune and adaptive immune responses. Desirable biosafety and marked therapeutic efficacy with a tumor growth inhibition (TGI) of 51.0% on the murine B16-F10 melanoma model were achieved by the single agent dsDNA@DMONs. Moreover, dsDNA@DMONs combined with anti-PD-L1 antibody further enhanced the anti-tumor efficacy and led to almost complete tumor regression. Therefore, this work highlighted the immunostimulatory DNA-based nanomedicine as a promising strategy for overcoming the resistance to immunotherapy, by promoting the IFN-Is production for innate immunity activation and remodeling the tumor microenvironment.

Hierarchical transcriptional network governing heterogeneous T cell exhaustion and its implications for immune checkpoint blockade

The fundamental principle of immune checkpoint blockade (ICB) is to protect tumor-infiltrating T cells from being exhausted. Despite the remarkable success achieved by ICB treatment, only a small group of patients benefit from it. Characterized by a hypofunctional state with the expression of multiple inhibitory receptors, exhausted T (Tex) cells are a major obstacle in improving ICB. T cell exhaustion is a progressive process which adapts to persistent antigen stimulation in chronic infections and cancers. In this review, we elucidate the heterogeneity of Tex cells and offer new insights into the hierarchical transcriptional regulation of T cell exhaustion. Factors and signaling pathways that induce and promote exhaustion are also summarized. Moreover, we review the epigenetic and metabolic alterations of Tex cells and discuss how PD-1 signaling affects the balance between T cell activation and exhaustion, aiming to provide more therapeutic targets for applications of combinational immunotherapies.

Improving the efficacy of combined radiotherapy and immunotherapy: focusing on the effects of radiosensitivity

Cancer treatment is gradually entering an era of precision, with multitude studies in gene testing and immunotherapy. Tumor cells can be recognized and eliminated by the immune system through the expression of tumor-associated antigens, but when the cancer escapes or otherwise suppresses immunity, the balance between cancer cell proliferation and immune-induced cancer cell killing may be interrupted, resulting in tumor proliferation and progression. There has been significant attention to combining conventional cancer therapies (i.e., radiotherapy) with immunotherapy as opposed to treatment alone. The combination of radio-immunotherapy has been demonstrated in both basic research and clinical trials to provide more effective anti-tumor responses. However, the absolute benefits of radio-immunotherapy are dependent on individual characteristics and not all patients can benefit from radio-immunotherapy. At present, there are numerous articles about exploring the optimal models for combination radio-immunotherapy, but the factors affecting the efficacy of the combination, especially with regard to radiosensitivity remain inconclusive. Radiosensitivity is a measure of the response of cells, tissues, or individuals to ionizing radiation, and various studies have shown that the radiosensitivity index (RSI) will be a potential biomarker for predicting the efficacy of combination radio-immunotherapy. The purpose of this review is to focus on the factors that influence and predict the radiosensitivity of tumor cells, and to evaluate the impact and predictive significance of radiosensitivity on the efficacy of radio-immunotherapy combination.

Hepatic failure associated with immune checkpoint inhibitors: An analysis of the Food and Drug Administration Adverse Event Reporting System database

BACKGROUND

Hepatic failure induced by immune checkpoint inhibitors (ICIs) has been reported in only a few case series and case reports.

OBJECTIVE

We aimed to explore the association between ICIs and hepatic failure and characterize the clinical features of ICI-associated hepatic failure in the pharmacovigilance database.

METHODS

Data from the first quarter (Q1) of 2015 to the fourth quarter (Q4) of 2021 in the US Food and Drug Administration Adverse Event Reporting System (FAERS) database were retrieved for disproportionality and Bayesian analysis. Reporting odds ratios (ROR) and information component (IC) were used to evaluate correlations between ICIs and hepatic failure.

RESULTS

Hepatic failure occurred in 0.19% (18,454/9,647,655) of all cases in the FAERS database, of which 654 cases were associated with ICIs. The overall median time from ICIs initiation to hepatic failure onset was 38 days, 72.3% of the adverse events occurred within the first 3 months, and 68.65% of the cases died after developing hepatic failure. In general, a strong signal was shown between ICIs and hepatic failure (ROR₀₂₅  = 2.70, IC₀₂₅  = 1.39). For the three categories of ICIs, programmed cell death 1 ligand 1 inhibitors (ROR₀₂₅  = 3.09, IC₀₂₅  = 1.57) had a higher risk signal than programmed cell death protein 1 inhibitors and cytotoxic T lymphocyte-associated protein 4 inhibitors. For monotherapy, atezolizumab showed the strongest risk signal (ROR₀₂₅  = 4.07, IC₀₂₅  = 1.90). The combination of nivolumab and ipilimumab showed stronger signals of hepatic failure compared with nivolumab or ipilimumab alone (nivolumab + ipilimumab vs. ipilimumab: ROR₀₂₅  = 1.40, IC₀₂₅  = 0.16; nivolumab + ipilimumab vs. nivolumab: ROR₀₂₅  = 1.24, IC₀₂₅  = 0.34). Considering the concomitant agents used with ICIs, the majority of these regimens showed stronger signals than ICI monotherapy, such as acetaminophen (ICIs + acetaminophen vs. ICIs: ROR₀₂₅  = 1.06, IC₀₂₅  = 0.32).

CONCLUSIONS

ICIs had possible strong signals associated with hepatic failure, and most cases of hepatic failure occurred within the first 3 months and had poor outcomes, which should attract clinical attention.

Identification and Validation of a Novel Glycolysis-Related Gene Signature for Predicting the Prognosis and Therapeutic Response in Triple-Negative Breast Cancer

INTRODUCTION

A high malignancy rate and poor prognosis are common problems with triple-negative breast cancer (TNBC). There is increasing evidence that glycolysis plays vital roles in tumorigenesis, tumor invasion, immune evasion, chemoresistance, and metastasis. However, a comprehensive analysis of the diagnostic and prognostic significance of glycolysis in TNBC is lacking.

METHODS

Transcriptomic and clinical data of TNBC patients were obtained from The Cancer Genome Atlas (TCGA) and Molecular Taxonomy of Breast Cancer International Consortium (METABRIC) databases, respectively. Glycolysis-related genes (GRGs) were collected from the Molecular Signatures Database (MSigDB). Differential comparative analysis was performed to obtain the differentially expressed (DE)-GRGs associated with TNBC. Based on the DE-GRGs, a glycolysis-related risk signature was established using Least Absolute Shrinkage and Selector Operation (LASSO) and multivariable Cox regression analyses. The prognostic value, tumor microenvironment, mutation status, and chemotherapy response of different risk groups were analyzed. An independent cohort from the METABRIC database was used for external validation. Furthermore, the expression patterns of five genes derived from the prognostic model were validated by quantitative real-time polymerase chain reaction (RT-qPCR).

RESULTS

The glycolysis-related prognostic signature included five genes (IFNG, ACSS2, IRS2, GFUS, and GAL3ST1) and predicted the prognosis of TNBC patients independent of clinical factors (p < 0.05). Patients were divided into high- and low-risk groups based on the median risk score. Compared to low-risk TNBC patients, high-risk patients had significantly decreased overall survival (HR = 2.718, p < 0.001). Receiver operating characteristic and calibration curves demonstrated that the model had high performance in terms of predicting survival and risk stratification. The results remained consistent after external verification. Additionally, the tumor immune microenvironment significantly differed between the risk groups. Low-risk TNBC patients had a better immunotherapy response than high-risk patients. High-risk TNBC patients with a poor prognosis may benefit from targeted therapy.

CONCLUSIONS

This study developed a novel glycolysis and prognosis-related (GRP) signature based on GRGs to predict the prognosis of TNBC patients, and may aid clinical decision-making for these patients.

Camrelizumab plus gemcitabine and oxaliplatin for the treatment of advanced intrahepatic cholangiocarcinoma: a bi-centric observational retrospective study

Background

Immune checkpoint inhibitor (ICI), coupled with systemic chemotherapy, may enhance the clinical benefit of cancer by potentiating antitumor immunity, but its efficacy and safety are not clear in advanced intrahepatic cholangiocarcinoma (ICC). This study aims to assess the efficacy and safety of camrelizumab plus gemcitabine and oxaliplatin (GEMOX) for the treatment of advanced ICC in the real world.

Methods

Advanced ICC patients receiving at least one session of camrelizumab plus GEMOX combination treatment from March 2020 to February 2022 at two high-volume centers were considered eligible. Tumor response was evaluated based on the Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST v1.1). The primary endpoint was objective response rate (ORR), disease control rate (DCR), time to response (TTR), and duration of response (DOR). The secondary end points included overall survival (OS), progression-free survival (PFS), and treatment-related adverse events (TRAEs).

Results

30 eligible ICC patients were enrolled and analyzed in this observational retrospective study. The median follow-up time was 24.0 (21.5-26.5) months. The ORR and DCR were 40% and 73.3%, respectively. The median TTR was 2.4 months and the median DOR was 5.0 months. The median PFS and OS were 7.5 months and 17.0 months, respectively. The most common TRAEs were fever (83.3%), fatigue (73.3%), and nausea (70%). Of all TRAEs, thrombocytopenia, and neutropenia were the most frequent severe AE (both 10%).

Conclusion

The combination of camrelizumab and GEMOX is a potentially efficacious and safe treatment modality for advanced ICC patients. Potential biomarkers are needed to identify patients who might benefit from this treatment option.

Novel antigens for targeted radioimmunotherapy in hepatocellular carcinoma

Liver cancer is the sixth common cancer and forth cause of cancer-related death worldwide. Based on usually advanced stages of hepatocellular carcinoma (HCC) at the time of diagnosis, therapeutic options are limited and, in many cases, not effective, and typically result in the tumor recurrence with a poor prognosis. Radioimmunotherapy (RIT) offers a selective internal radiation therapy approach using beta or alpha emitting radionuclides conjugated with tumor-specific monoclonal antibodies (mAbs), or specific selective peptides. When compared to chemotherapy or radiotherapy, radiolabeled mAbs against cancer-associated antigens could provide a high therapeutic and exclusive radiation dose for cancerous cells while decreasing the exposure-induced side effects to healthy tissues. The recent advances in cancer immunotherapy, such as blockade of immune-checkpoint inhibitors (ICIs), has changed the landscape of cancer therapy, and the efficacy of different classes of immunotherapy has been tested in many clinical trials. Taking into account the use of ICIs in the liver tumor microenvironment, combined therapies with different approaches may enhance the outcome in the future clinical studies. With the development of novel immunotherapy treatment options in the recent years, there has been a great deal of information about combining the diverse treatment modalities to boost the effectiveness of immunomodulatory drugs. In this opinion review, we will discuss the recent advancements in RIT. The current status of immunotherapy and internal radiotherapy will be updated, and we will propose novel approaches for the combination of both techniques. Potential target antigens for radioimmunotherapy in Hepatocellular carcinoma (HCC). HCC radioimmunotherapy target antigens are the most specific and commonly accessible antigens on the surface of HCC cells. CTLA-4 ligand and receptor, TAMs, PD-1/PD-L, TIM-3, specific IEXs/TEXs, ROBO1, and cluster of differentiation antigens CD105, CD147 could all be used in HCC radioimmunotherapy. Abbreviations: TAMs, tumor-associated macrophages; CTLA-4, cytotoxic T-lymphocyte associated antigen-4; PD-1, Programmed cell death protein 1; PD-L, programmed death-ligand1; TIM-3, T-cell immunoglobulin (Ig) and mucin-domain containing protein-3; IEXs, immune cell-derived exosomes; TEXs, tumor-derived exosomes.

Mechanisms of CAR T cell exhaustion and current counteraction strategies

The functional state of chimeric antigen receptor T (CAR T) cells determines their efficacy in vivo. Exhausted CAR T cells exhibit decreased proliferative capacity, impaired anti-tumor activity, and attenuated persistence. CAR T cell exhaustion has been recognized as a vital cause of nonresponse and relapse after CAR T cell therapy. However, the triggers and mechanisms leading to CAR T cell exhaustion remain blurry and complicated. Therefore, it is essential to clear the regulation network of CAR T cell exhaustion and explore potent solutions. Here, we review the diverse inducers of CAR T cell exhaustion in terms of manufacture process and immunosuppressive tumor microenvironment. In addition to the admitted immune checkpoint blockade, we also describe promising strategies that may reverse CAR T cell exhaustion including targeting the tumor microenvironment, epigenetics and transcriptomics.

Modification of the Tumor Microenvironment Enhances Anti-PD-1 Immunotherapy in Metastatic Melanoma

Resistance to checkpoint-blockade treatments is a challenge in the clinic. Both primary and acquired resistance have become major obstacles, greatly limiting the long-lasting effects and wide application of blockade therapy. Many patients with metastatic melanoma eventually require further therapy. The absence of T-cell infiltration to the tumor site is a well-accepted contributor limiting immune checkpoint inhibitor efficacy. In this study, we combined intratumoral injection of plasmid IL-12 with electrotransfer and anti-PD-1 in metastatic B16F10 melanoma tumor model to increase tumor-infiltrating lymphocytes and improve therapeutic efficacy. We showed that effective anti-tumor responses required a subset of tumor-infiltrating CD8+ and CD4+ T cells. Additionally, the combination therapy induced higher MHC-I surface expression on tumor cells to hamper tumor cells escaping from immune recognition. Furthermore, we found that activating T cells by exposure to IL-12 resulted in tumors sensitized to anti-PD-1 treatment, suggesting a therapeutic strategy to improve responses to checkpoint blockade.

GNAI2 Is a Risk Factor for Gastric Cancer: Study of Tumor Microenvironment (TME) and Establishment of Immune Risk Score (IRS)

Purpose

Although the G protein subunit α i2 (GNAI2) is upregulated in multiple cancers, its prognostic value and exact role in the development of gastric cancer (GC) remain largely unknown.

Methods

This study evaluated the effect of GNAI2 on the tumor microenvironment (TME) in GC, constructed an immune risk score (IRS) model based on differentially-expressed immune genes, and systematically correlated GNAI2 and epigenetic factor expression patterns with TME and IRS. Also, RT-qPCR, flow cytometry, Western blotting (WB), and transwell assays were carried out to explore the regulatory mechanism of GNAI2 in GC.

Results

High GNAI2 expression was associated with poor prognosis. Cytokine activation, an increase in tumor-infiltrating immune cells (TIIC), and the accumulation of regulatory T cells in the tumor immune cycle were all promoted by the TME, which was significantly associated with GNAI2 expression. Two different differentially expressed mRNA (DER) modification patterns were determined. These two DERs-clusters had significantly different TME cell infiltrations and were classified as either noninflamed or immune-inflamed phenotypes. The IRS model constructed using differentially expressed genes (DEGs) had great potential in predicting GC prognosis. The IRS model was also used in assessing clinicopathological features, such as microsatellite instability (MSI) status, epithelial-mesenchymal transition (EMT) status, clinical stages, tumor mutational burden (TMB), and tumor immune dysfunction and exclusion (TIDE) scores. Low IRS scores were associated with high immune checkpoint gene expression. Cell and animal studies confirmed that GNAI2 activated PI3K/AKT pathway and promoted the growth and migration of GC cells.

Conclusion

The IRS model can be used for survival prediction and GNAI2 serves as a candidate therapeutic target for GC patients.

Efficacy and safety of sintilimab plus XELOX as a neoadjuvant regimen in patients with locally advanced gastric cancer: A single-arm, open-label, phase II trial

Background

Neoadjuvant chemotherapies have been widely recommended in patients with locally advanced gastric cancer (LAGC). However, the evidence of combining neoadjuvant chemotherapy with anti–programmed death 1 (anti–PD-1) antibody therapy for patients with LAGC is lacking. Thus, we conducted a single-arm phase II trial to evaluate the efficacy and safety of the anti–PD-1 antibody sintilimab plus XELOX regimen (capecitabine plus oxaliplatin) in patients with LAGC.

Methods

Patients with LAGC (cT3-4 N+ M0, CY0, P0) were enrolled and received four preoperative cycles of sintilimab (200 mg, IV, Q21d) plus XELOX (oxaliplatin 130 mg/m², IV, d1 with capecitabine 1,000 mg/m², bid, d1–d14, Q21d) therapy. The primary endpoint was the pathological complete response (pCR) rate. This clinical trial was registered at Chictr.org.cn (trial number: ChiCTR2000030414).

Results

Thirty patients were enrolled from March 2020 to July 2021, with a median age of 62 years (range, 30–72), and 18 (60.0%) were men. There were 19 (63.3%) patients with PD-L1 CPS ≥1.The pCR rate was 33.3% [95% confidence interval (CI), 17.3%–52.8%], and the major pathologic response (MPR) rate was 63.3% (95% CI, 43.9%–80.1%). All the patients underwent R0 resection. The objective response rate (ORR) and the disease control rate (DCR) were 70.0% (95% CI, 50.6%–85.3%) and 100% (95% CI, 88.4%–100%), respectively. Downstaging of the overall TNM stage was observed in 22 (73.3%) patients. The pCR rate in patients with PD-L1 CPS ≥1 and patients with PD-L1 CPS <1 was 42.1% vs. 18.2% (P = 0.246), whereas the MPR rate was 78.9% vs. 36.4% (P = 0.047). The potential immune-related adverse events (irAEs) were hypothyroidism (3.3%), pneumonia (10.0%), and dermatitis (6.7%). Grade3 common treatment-related adverse events (TRAEs) were ALT increase (3.3%), AST increase (3.3%), and dermatitis (3.3%) during the neoadjuvant therapy. There were no severe complications or death related to the surgery.

Conclusion

Sintilimab plus XELOX as neoadjuvant therapy showed an encouraging pCR rate, MPR rate, and manageable safety. This combination of regimens might provide a new option for patients with LAGC.

Clinical Trial Registration: Chictr.org.cn, identifier ChiCTR2000030414.

Neutrophils: Musketeers against immunotherapy

Neutrophils, the most copious leukocytes in human blood, play a critical role in tumorigenesis, cancer progression, and immune suppression. Recently, neutrophils have attracted the attention of researchers, immunologists, and oncologists because of their potential role in orchestrating immune evasion in human diseases including cancer, which has led to a hot debate redefining the contribution of neutrophils in tumor progression and immunity. To make this debate fruitful, this review seeks to provide a recent update about the contribution of neutrophils in immune suppression and tumor progression. Here, we first described the molecular pathways through which neutrophils aid in cancer progression and orchestrate immune suppression/evasion. Later, we summarized the underlying molecular mechanisms of neutrophil-mediated therapy resistance and highlighted various approaches through which neutrophil antagonism may heighten the efficacy of the immune checkpoint blockade therapy. Finally, we have highlighted several unsolved questions and hope that answering these questions will provide a new avenue toward immunotherapy revolution.

Inhibition of hyperprogressive cancer disease induced by immune-checkpoint blockade upon co-treatment with meta-tyrosine and p38 pathway inhibitor

Background

Although immune-checkpoint inhibitors (ICI) are overall promissory for cancer treatment, they entail, in some cases, an undesired side-effect called hyperprogressive-cancer disease (HPD) associated with acceleration of tumor growth and shortened survival.

Methods

To understand the mechanisms of HPD we assayed the ICI therapy on two murine tumors widely different regarding immunogenicity and, subsequently, on models of local recurrences and metastases of these tumors. To potentiate the immune response (IR), we combined ICI with meta-tyrosine—that counteracts immune-suppressive signals—and a selective inhibitor of p38 pathway that proved to counteract the phenomenon of tumor-immunostimulation.

Results

ICI were therapeutically effective against both tumor models (proportionally to their immunogenicity) but only when they faced incipient tumors. In contrast, ICI produced acceleration of large and residual tumors. The combined treatment strongly inhibited the growth of large tumors and it managed to cure 80% of mice with local recurrences and 60% of mice bearing residual metastases.

Conclusions

Tumor enhancement was paradoxically correlated to a weak increase of the antitumor IR suggesting that a weak IR – different from a strong tumor-inhibitory one—may produce stimulation of tumor growth, mimicking the HPD observed in some clinical settings.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-09941-2.

Combination Immune Checkpoint Blockade Regimens for Previously Untreated Metastatic Renal Cell Carcinoma: The Winship Cancer Institute of Emory University Experience

Introduction

There are three combination immune checkpoint inhibitor (ICI)-based regimens in the first-line setting for metastatic renal cell carcinoma (mRCC). Currently, there is limited real-world data for clinical outcomes and toxicity in mRCC patients treated with first-line ICI-based regimens.

Methods

We performed a retrospective review of 49 mRCC patients treated with ICI-based combination regimens in the standard of care setting at the Winship Cancer Institute of Emory University from 2015-2020. We collected baseline data from the electronic medical record including demographic information and disease characteristics. Immune-related adverse events (irAEs) were collected from clinic notes and laboratory values. The primary clinical outcomes measured were overall survival (OS), progression-free survival (PFS), and objective response rate (ORR).

Results

The median age was 65 years, and most patients (80%) were males. The majority were White (86%) and had clear cell RCC (83%). Most patients had an Eastern Cooperative Oncology Group (ECOG) performance status score of 0 (43%) or 1 (45%). Approximately one-half (49%) had at least three sites of distant metastatic disease. Most patients (88%) received nivolumab and ipilimumab. More than one-half (53%) of patients experienced an irAE, with 13 (27%) patients having treatment delayed and 18% discontinuing treatment for toxicity. The median OS was not reached, and the median PFS was 8.0 months per a Kaplan-Meier estimation. More than half of patients (53%) had a PFS > 6 months, and 22% had PFS > 1 year. The ORR was 33% for the entire cohort, and 7% of patients had a complete response.

Conclusion

We presented real-world efficacy and toxicity data for front-line ICI combination treatment regimens. The ORR and median PFS were lower in our cohort of patients compared to the available data in the clinical trial setting. This was likely because of more advanced disease in this study. Future studies should provide additional data that will allow comparisons between different ICI combination regimens for untreated mRCC.

IGSF11 and VISTA: a pair of promising immune checkpoints in tumor immunotherapy

Immunotherapy has become the major treatment for tumors in clinical practice, but some intractable problems such as the low response rate and high rates of immune-related adverse events still hinder the progress of tumor immunotherapy. Hence, it is essential to explore additional immunotherapy treatment targets. In this review, we focus on the structure, expression and expression-related mechanisms, interactions, biological functions and the progress in preclinical/clinical research of IGSF11 and VISTA in tumors. We cover the progress in recent research with this pair of immune checkpoints in tumor immune regulation, proliferation, immune resistance and predictive prognosis. Both IGSF11 and VISTA are highly expressed in tumors and are modulated by various factors. They co-participate in the functional regulation of immune cells and the inhibition of cytokine production. Besides, in the downregulation of IGSF11 and VISTA, both inhibit the growth of some tumors. Preclinical and clinical trials all emphasize the predictive role of IGSF11 and VISTA in the prognosis of tumors, and that the predictive role of the same gene varies from tumor to tumor. At present, further research is proving the enormous potential of IGSF11 and VISTA in tumors, and especially the role of VISTA in tumor immune resistance. This may prove to be a breakthrough to solve the current clinical immune resistance, and most importantly, since research has focused on VISTA but less on IGSF11, IGSF11 may be the next candidate for tumor immunotherapy.

The strategic roles of four enzymes in the interconnection between metabolism and oncogene activation in non-small cell lung cancer: Therapeutic implications

NSCLC is the leading cause of cancer mortality and represents a major challenge in cancer therapy. Intrinsic and acquired anticancer drug resistance are promoted by hypoxia and HIF-1α. Moreover, chemoresistance is sustained by the activation of key signaling pathways (such as RAS and its well-known downstream targets PI3K/AKT and MAPK) and several mutated oncogenes (including KRAS and EGFR among others). In this review, we highlight how these oncogenic factors are interconnected with cell metabolism (aerobic glycolysis, glutaminolysis and lipid synthesis). Also, we stress the key role of four metabolic enzymes (PFK1, dimeric-PKM2, GLS1 and ACLY), which promote the activation of these oncogenic pathways in a positive feedback loop. These four tenors orchestrating the coordination of metabolism and oncogenic pathways could be key druggable targets for specific inhibition. Since PFK1 appears as the first tenor of this orchestra, its inhibition (and/or that of its main activator PFK2/PFKFB3) could be an efficacious strategy against NSCLC. Citrate is a potent physiologic inhibitor of both PFK1 and PFKFB3, and NSCLC cells seem to maintain a low citrate level to sustain aerobic glycolysis and the PFK1/PI3K/EGFR axis. Awaiting the development of specific non-toxic inhibitors of PFK1 and PFK2/PFKFB3, we propose to test strategies increasing citrate levels in NSCLC tumors to disrupt this interconnection. This could be attempted by evaluating inhibitors of the citrate-consuming enzyme ACLY and/or by direct administration of citrate at high doses. In preclinical models, this "citrate strategy" efficiently inhibits PFK1/PFK2, HIF-1α, and IGFR/PI3K/AKT axes. It also blocks tumor growth in RAS-driven lung cancer models, reversing dedifferentiation, promoting T lymphocytes tumor infiltration, and increasing sensitivity to cytotoxic drugs.

In vivo multidimensional CRISPR screens identify Lgals2 as an immunotherapy target in triple-negative breast cancer

Immune checkpoint inhibitors exhibit limited response rates in patients with triple-negative breast cancer (TNBC), suggesting that additional immune escape mechanisms may exist. Here, we performed two-step customized in vivo CRISPR screens targeting disease-related immune genes using different mouse models with multidimensional immune-deficiency characteristics. In vivo screens characterized gene functions in the different tumor microenvironments and recovered canonical immunotherapy targets such as Ido1. In addition, functional screening and transcriptomic analysis identified Lgals2 as a candidate regulator in TNBC involving immune escape. Mechanistic studies demonstrated that tumor cell-intrinsic Lgals2 induced the increased number of tumor-associated macrophages, as well as the M2-like polarization and proliferation of macrophages through the CSF1/CSF1R axis, which resulted in the immunosuppressive nature of the TNBC microenvironment. Blockade of LGALS2 using an inhibitory antibody successfully arrested tumor growth and reversed the immune suppression. Collectively, our results provide a theoretical basis for LGALS2 as a potential immunotherapy target in TNBC.

Successful Treatment of Metastatic Gallbladder Carcinoma with PD-L1 Expression by the Combination of PD-1 Inhibitor Plus Bevacizumab with Chemotherapy: A Case Report

Gallbladder cancer (GBC) is the most common type of biliary tract cancer. The GBC is often diagnosed at an advanced stage, which limits surgical intervention due to its aggressive nature, and as a consequence of its insensitivity to chemotherapy, more effective treatments are required. In GBC, the efficacy of chemotherapy combined with anti-PD-L1/VEGF inhibition remains to be clarified. The present case report describes successful treatment by toripalimab in combination with bevacizumab and gemcitabine in a patient with metastatic GBC and PD-L1 combined positive score (CPS) =30. After six courses of therapy, a partial response was observed in the patient’s clinical condition. So far, her PFS has exceeded 15 months. To the best of our knowledge, there was no other case where toripalimab plus bevacizumab were used in combination with gemcitabine as an effective treatment strategy for GBC. The remarkable response is likely to be related to the positive expression of PD-L1. Further, VEGF inhibition in combination with chemotherapy may result in improved clinical outcomes due to increased antitumor immunity. Chemotherapy regimens combined with anti-PD-L1/VEGF inhibition are promising therapies for GBC. Further well-designed prospective clinical trials are needed in order to confirm the efficacy and safety of the three-drug regimen.

Immunotherapy for Management of Thymic Epithelial Tumors: A Double-Edged Sword

Thymic epithelial tumors (TETs) are rare thoracic cancers that are broadly classified as thymomas and thymic carcinomas. Surgery is the cornerstone of management for early-stage disease. There are a limited number of effective treatment options for patients with advanced or recurrent disease. The occurrence of paraneoplastic autoimmune disorders in patients with TETs, especially thymomas, creates significant challenges for the development of immunotherapy, including immune checkpoint inhibitors, as a feasible treatment option. In addition, patients with TETs are at increased risk for the development of immune-mediated toxicity with a predilection for musculoskeletal and neuromuscular adverse events upon treatment with immunotherapy. The identification of biomarkers of response and toxicity is expected to play a key role in harnessing the benefits of immunotherapy for patients with TETs. In this paper we review the biology of TETs and the potential effects on the tolerability of immunotherapy. The results of clinical trials of immune checkpoint inhibitors for the treatment of advanced TETs are described to understand the potential risks and benefits of immunotherapy. We also provide an overview of future avenues for treatment with novel immunotherapeutic modalities and opportunities to develop biomarkers to improve the safety and tolerability of immunomodulatory treatments in patients with TETs.

Checkpoint Inhibitor Pneumonitis Induced by Anti-PD-1/PD-L1 Therapy in Non-Small-Cell Lung Cancer: Occurrence and Mechanism

Immune checkpointty inhibitors (ICIs), particularly those targeting programmed death 1 (PD-1) and anti-programmed death ligand 1 (PD-L1), enhance the antitumor effect by restoring the function of the inhibited effector T cells and produce durable responses in a large variety of metastatic and late patients with non-small-cell lung cancer. Although often well tolerated, the activation of the immune system results in side effects known as immune-related adverse events (irAEs), which can affect multiple organ systems, including the lungs. The occurrence of severe pulmonary irAEs, especially checkpoint inhibitor pneumonitis (CIP), is rare but has extremely high mortality and often overlaps with the respiratory symptoms and imaging of primary tumors. The development of CIP may be accompanied by radiation pneumonia and infectious pneumonia, leading to the simultaneous occurrence of a mixture of several types of inflammation in the lungs. However, there is a lack of authoritative diagnosis, grading criteria and clarified mechanisms of CIP. In this article, we review the incidence and median time to onset of CIP in patients with non-small-cell lung cancer treated with PD-1/PD-L1 blockade in clinical studies. We also summarize the clinical features, potential mechanisms, management and predictive biomarkers of CIP caused by PD-1/PD-L1 blockade in non-small-cell lung cancer treatment.

Efficacy and Safety of Low-Dose Nab-Paclitaxel Plus Tislelizumab in Elderly Patients With Previously Treated Metastatic Non-Small Cell Lung Cancer

The combination of immunotherapy and chemotherapy has a synergic effect in non-small cell lung cancer (NSCLC). However, the elderly are often excluded from clinical trails due to their poor health status and more comorbidities. We sought to assess the efficacy and safety of low-dose nanoparticle albumin-bound paclitaxel (nab-paclitaxel) plus tislelizumab (an anti-PD-1 antibody) in elderly patients with advanced NSCLC. In this phase 2 clinical trail, eligible patients were those aged ≥65 years with metastatic NSCLC who had disease progression after treatment with ≥1 line of chemotherapy or targeted therapy. Patients with epidermal growth factor receptor (EGFR) or anaplastic lymphoma kinase (ALK) variations were eligible if they demonstrated disease progression after treatment with ≥1 corresponding inhibitor. Primary endpoints were progression-free survival and safety/tolerability. Secondary endpoints included objective response rate and overall survival. Among 29 patients enrolled from May 2019 through August 2020, 21 (72.4%) had adenocarcinoma, 17 (58.6%) had a performance status of 2, 8 (27.6%) had asymptomatic brain metastases, and 13 (44.8%) had EGFR/ALK variations. As of the data cutoff point on April 1, 2021, median progression-free survival and overall survival were 9.5 months and 16.5 months, respectively. Ten patients achieved a partial response (objective response rate of 34.5%). Seventeen (58.6%) patients had ≥1 treatment-related adverse event, with grade 3 events seen in 3 patients (10.3%). The most common adverse events were fatigue (20.7%), fever (17.2%), abnormal liver function (17.2%), and rash (17.2%). These results suggest that low-dose nab-paclitaxel plus tislelizumab is well tolerated and effective in elderly patients with advanced NSCLC, including those with EGFR/ALK variations.

Adjuvant Therapy With PD1/PDL1 Inhibitors for Human Cancers: A Systematic Review and Meta-Analysis

Background

Immune checkpoint inhibitors (ICIs) have made a breakthrough in the systemic treatment of patients with advanced tumors. However, little is known about their efficacy and safety in adjuvant settings after the resection of solid tumors.

Methods

We performed a meta-analysis on the efficacy and safety of programmed death 1 (PD1)/PD-1 ligand (PDL1) inhibitors in adjuvant therapy after tumor resection using Review Manager 5.3, based on published clinical studies. The outcomes included recurrence-free survival (RFS), disease-free survival (DFS), overall survival (OS), and adverse events (AEs).

Results

Eight randomized controlled trials (RCTs) were included in the analysis. The use of PD1/PDL1 inhibitors in adjuvant therapy significantly improved RFS (hazard ratio [HR] = 0.72; 95% confidence interval [CI] 0.67–0.78, p < 0.00001). However, there was no statistically significant difference in OS between PD1/PDL1 inhibitors and placebo (HR = 0.86; 95% CI 0.74–1.00, p = 0.05). Gender, age, and PDL1 status were independent predictors of RFS with PD1/PDL1 inhibitors. As for the safety analysis results, PD1/PDL1 inhibitors had a higher incidence of fatigue (risk ratio [RR] = 1.22; 95% CI 1.01–1.49, p = 0.04), nausea (RR = 1.47; 95% CI 1.11–1.94, p = 0.007), and pruritus (RR = 1.96; 95% CI 1.57–2.44, p < 0.00001). In addition, the incidence of any grade adverse events increased in the PD1/PDL1 inhibitor group (RR = 1.03; 95% CI 1.02–1.05, p < 0.0001).

Conclusions

This is the first meta-analysis on the efficacy and safety of PD1/PDL1 inhibitors in adjuvant therapy. The use of PD1/PDL1 inhibitors in adjuvant therapy could significantly reduce the recurrence rate after solid tumor resection. However, the incidence of fatigue, nausea, pruritus, and any grade AEs also increased, which should be monitored with vigilance.

YPD-30, a prodrug of YPD-29B, is an oral small-molecule inhibitor targeting PD-L1 for the treatment of human cancer

PD-1 and PD-L1 antibodies have brought about extraordinary clinical benefits for cancer patients, and their indications are expanding incessantly. Currently, most PD-1/PD-L1 agents are administered intravenously, which may be uncomfortable for some cancer patients. Herein, we develop a novel oral-delivered small molecular, YPD-29B, which specifically targets human PD-L1. Our data suggested that YPD-29B could potently and selectively block the interaction between PD-L1 and PD-1, but did not inhibit any other immune checkpoints. Mechanistically, YPD-29B induced human PD-L1 dimerization and internalization, which subsequently activated T lymphocytes and therefore overcomes immunity tolerance in vitro. YDP-29B was modified as the YPD-30 prodrug to improve druggability. Using humanized mice with human PD-1 xenografts of human PD-L1 knock-in mouse MC38 cancer cells, we demonstrated that YPD-30 exhibited significant antitumor activity and was well tolerated in vivo. Taken together, our results indicate that YPD-30 serves as a promising therapeutic candidate for anti-human PD-L1 cancer immunotherapy.

Atezolizumab Treatment for Progressive Multifocal Leukoencephalopathy

Atezolizumab successfully reinvigorated JC virus immunity in a patient in Belgium with progressive multifocal leukoencephalopathy, as demonstrated by clinical, virologic, and radiologic response to treatment. However, the treatment also resulted in immune reconstitution inflammatory syndrome and life-threatening immune-related adverse events. These conditions were treated with corticosteroids, leading to treatment resistance.

Impact of cancer metabolism on therapy resistance - Clinical implications

Despite an increasing arsenal of anticancer therapies, many patients continue to have poor outcomes due to the therapeutic failures and tumor relapses. Indeed, the clinical efficacy of anticancer therapies is markedly limited by intrinsic and/or acquired resistance mechanisms that can occur in any tumor type and with any treatment. Thus, there is an urgent clinical need to implement fundamental changes in the tumor treatment paradigm by the development of new experimental strategies that can help to predict the occurrence of clinical drug resistance and to identify alternative therapeutic options. Apart from mutation-driven resistance mechanisms, tumor microenvironment (TME) conditions generate an intratumoral phenotypic heterogeneity that supports disease progression and dismal outcomes. Tumor cell metabolism is a prototypical example of dynamic, heterogeneous, and adaptive phenotypic trait, resulting from the combination of intrinsic [(epi)genetic changes, tissue of origin and differentiation dependency] and extrinsic (oxygen and nutrient availability, metabolic interactions within the TME) factors, enabling cancer cells to survive, metastasize and develop resistance to anticancer therapies. In this review, we summarize the current knowledge regarding metabolism-based mechanisms conferring adaptive resistance to chemo-, radio-and immunotherapies as well as targeted therapies. Furthermore, we report the role of TME-mediated intratumoral metabolic heterogeneity in therapy resistance and how adaptations in amino acid, glucose, and lipid metabolism support the growth of therapy-resistant cancers and/or cellular subpopulations. We also report the intricate interplay between tumor signaling and metabolic pathways in cancer cells and discuss how manipulating key metabolic enzymes and/or providing dietary changes may help to eradicate relapse-sustaining cancer cells. Finally, in the current era of personalized medicine, we describe the strategies that may be applied to implement metabolic profiling for tumor imaging, biomarker identification, selection of tailored treatments and monitoring therapy response during the clinical management of cancer patients.

Why may citrate sodium significantly increase the effectiveness of transarterial chemoembolization in hepatocellular carcinoma?

Hepatocellular carcinoma (HCC) represents the third cause of cancer death in men worldwide, and its increasing incidence can be explained by the increasing occurrence of non-alcoholic steatohepatitis (NASH). HCC prognosis is poor, as its 5-year overall survival is approximately 18 % and most cases are diagnosed at an inoperable advanced stage. Moreover, tumor sensitivity to conventional chemotherapeutics (particularly to cisplatin-based regimen), trans-arterial chemoembolization (cTACE), tyrosine kinase inhibitors, anti-angiogenic molecules and immune checkpoint inhibitors is limited. Oncogenic signaling pathways, such as HIF-1α and RAS/PI3K/AKT, may provoke drug resistance by enhancing the aerobic glycolysis ("Warburg effect") in cancer cells. Indeed, this metabolism, which promotes cancer cell development and aggressiveness, also induces extracellular acidity. In turn, this acidity promotes the protonation of drugs, hence abrogating their internalization, since they are most often weakly basic molecules. Consequently, targeting the Warburg effect in these cancer cells (which in turn would reduce the extracellular acidification) could be an effective strategy to increase the delivery of drugs into the tumor. Phosphofructokinase-1 (PFK1) and its activator PFK2 are the main regulators of glycolysis, and they also couple the enhancement of glycolysis to the activation of key signaling cascades and cell cycle progression. Therefore, targeting this "Gordian Knot" in HCC cells would be of crucial importance. Here, we suggest that this could be achieved by citrate administration at high concentration, because citrate is a physiologic inhibitor of PFK1 and PFK2. As shown in various in vitro studies, including HCC cell lines, administration of high concentrations of citrate inhibits PFK1 and PFK2 (and consequently glycolysis), decreases ATP production, counteracts HIF-1α and PI3K/AKT signaling, induces apoptosis, and sensitizes cells to cisplatin treatment. Administration of high concentrations of citrate in animal models (including Ras-driven tumours) has been shown to effectively inhibit cancer growth, reverse cell dedifferentiation, and neutralize intratumor acidity, without apparent toxicity in animal studies. Citrate may also induce a rapid secretion of pro-inflammatory cytokines by macrophages, and it could favour the destruction of cancer stem cells (CSCs) sustaining tumor recurrence. Consequently, this "citrate strategy" could improve the tumor sensitivity to current treatments of HCC by reducing the extracellular acidity, thus enhancing the delivery of chemotherapeutic drugs into the tumor. Therefore, we propose that this strategy should be explored in clinical trials, in particular to enhance cTACE effectiveness.

Hypoxia as a driver of resistance to immunotherapy

Hypoxia, a hallmark of solid tumors, determines the selection of invasive and aggressive malignant clones displaying resistance to radiotherapy, conventional chemotherapy or targeted therapy. The recent introduction of immunotherapy, based on immune checkpoint inhibitors (ICPIs) and chimeric antigen receptor (CAR) T-cells, has markedly transformed the prognosis in some tumors but also revealed the existence of intrinsic or acquired drug resistance. In the current review we highlight hypoxia as a culprit of immunotherapy failure. Indeed, multiple metabolic cross talks between tumor and stromal cells determine the prevalence of immunosuppressive populations within the hypoxic tumor microenvironment and confer upon tumor cells resistance to ICPIs and CAR T-cells. Notably, hypoxia-triggered angiogenesis causes immunosuppression, adding another piece to the puzzle of hypoxia-induced immunoresistance. If these factors concurrently contribute to the resistance to immunotherapy, they also unveil an unexpected Achille's heel of hypoxic tumors, providing the basis for innovative combination therapies that may rescue the efficacy of ICPIs and CAR T-cells. Although these treatments reveal both a bright side and a dark side in terms of efficacy and safety in clinical trials, they represent the future solution to enhance the efficacy of immunotherapy against hypoxic and therapy-resistant solid tumors.

Combined treatment of non-small cell lung cancer using radiotherapy and immunotherapy: challenges and updates

The efficacy of immunotherapy for advanced non‐small cell lung cancer (NSCLC) remains unsatisfactory, as the majority of patients either do not experience an objective response or acquire secondary resistance. As a result, several methods to enhance the systemic efficacy of immunotherapy have been investigated, including a large area of active research by combining immunotherapy with radiation therapy (RT). Given the rapidly burgeoning concept of combining immunotherapy and RT for increasing therapeutic benefit, we review the progress in this field thus far and explore further avenues for enhancing this combination. This review commences with a discussion of the only two existing randomized trials (and a pooled analysis) showing that the addition of RT to immunotherapy improves the abscopal response rate, progression‐free survival, and overall survival in metastatic NSCLC patients. We then discussed factors and biomarkers that may be associated with a proportionally greater benefit to additional RT, such as low programmed cell death protein ligand 1 (PD‐L1) status, tumor mutational burden (TMB), and patient's immune function. Next, the implementation of RT to overcome immunotherapy resistance is discussed, including a mechanistic discussion and methods with which these mechanisms could be exploited. Lastly, the emerging role of low‐dose RT is discussed, which may help to overcome inhibitory signals in the tumor stroma that limit T‐cell infiltration. Taken together, given the current state of this rapidly expanding realm, these futuristic strategies may be reflected upon to further enhance the efficacy of immunotherapy for a wider group of patients.

Targeting Tim-3 in Cancer With Resistance to PD-1/PD-L1 Blockade

Programmed death receptor 1 (PD-1) or programmed death ligand 1 (PD-L1) blocking therapy has completely changed the treatment pattern of malignant tumors. It has been tested in a wide range of malignant tumors and achieved clinical success. It might be a promising cancer treatment strategy. However, one of the important disadvantages of PD-1/PD-L1 blocking therapy is that only a few patients have a positive response to it. In addition, primary or acquired drug resistance can also lead to cancer recurrence in patients with clinical response. Therefore, it is very important to overcome the resistance of PD-1/PD-L1 blocking therapy and improve the overall response rate of patients to the immunotherapy. T cell immunoglobulin and mucin domain molecule 3 (Tim-3) belongs to the co-inhibitory receptor family involved in immune checkpoint function. Due to adaptive resistance, the expression of Tim-3 is up-regulated in PD-1/PD-L1 blocking therapy resistant tumors. Therefore, blocking the immune checkpoint Tim-3 might antagonize the resistance of PD-1/PD-L1 blocking therapy. This review systematically introduces the preclinical and clinical data of combined blockade of Tim-3 and PD-1/PD-L1 in cancer immunotherapy, and discusses the prospect of overcoming the drug resistance of PD-1/PD-L1 blockade therapy through blockade of Tim-3.

Semi-Mechanistic Model for the Antitumor Response of a Combination Cocktail of Immuno-Modulators in Non-Inflamed (Cold) Tumors

Simple Summary

The clinical efficacy of immunotherapies when treating cold tumors is still low, and different treatment combinations are needed when dealing with this challenging scenario. In this work, a middle-out strategy was followed to develop a model describing the antitumor efficacy of different immune-modulator combinations, including an antigen, a toll-like receptor-3 agonist, and an immune checkpoint inhibitor in mice treated with non-inflamed tumor cells. Our results support that clinical response requires antigen-presenting cell activation and also relies on the amount of CD8 T cells and tumor resistance mechanisms present. This mathematical model is a very useful platform to evaluate different immuno-oncology combinations in both preclinical and clinical settings.

Abstract

Immune checkpoint inhibitors, administered as single agents, have demonstrated clinical efficacy. However, when treating cold tumors, different combination strategies are needed. This work aims to develop a semi-mechanistic model describing the antitumor efficacy of immunotherapy combinations in cold tumors. Tumor size of mice treated with TC-1/A9 non-inflamed tumors and the drug effects of an antigen, a toll-like receptor-3 agonist (PIC), and an immune checkpoint inhibitor (anti-programmed cell death 1 antibody) were modeled using Monolix and following a middle-out strategy. Tumor growth was best characterized by an exponential model with an estimated initial tumor size of 19.5 mm³ and a doubling time of 3.6 days. In the treatment groups, contrary to the lack of response observed in monotherapy, combinations including the antigen were able to induce an antitumor response. The final model successfully captured the 23% increase in the probability of cure from bi-therapy to triple-therapy. Moreover, our work supports that CD8⁺ T lymphocytes and resistance mechanisms are strongly related to the clinical outcome. The activation of antigen-presenting cells might be needed to achieve an antitumor response in reduced immunogenic tumors when combined with other immunotherapies. These models can be used as a platform to evaluate different immuno-oncology combinations in preclinical and clinical scenarios.

The role of immunotherapy for management of advanced thymic epithelial tumors: a narrative review

The emergence of immunotherapy as a modern pillar of cancer treatment has changed the treatment landscape for various cancers. Immune checkpoint inhibitors directed at programed death-1 (PD-1) or its ligand (PD-L1), in particular, have found widespread clinical applications and have resulted in durable responses and an improvement in survival of patients with advanced or metastatic disease. Tumor cell PD-L1 expression and tumor mutation burden (TMB) are biomarkers of response and efforts are underway to identify other biomarkers that might predict benefit with these drugs. Most patients tolerate immunotherapy well, although a subset of patients develop immune-mediated toxicity due to excessive immune stimulation. Thymic epithelial tumors (TETs) have a unique biology which can predispose to development of autoimmune paraneoplastic disease, especially in patients with thymoma. Due to defects in immunological self-tolerance, the use of immunotherapy in TET patients is associated with an increased risk of immune-mediated adverse events, which can be potentially life-threatening. Development of biomarkers of response and toxicity is particularly important for the treatment of TETs since it is important to identify patients who might benefit from treatment and be at low risk for development of severe immune toxicity. The use of immunotherapy in patients with autoimmune disorders and those who have previously experienced immune-mediated toxicity is currently an area of active research. Various risk mitigation strategies are under evaluation in prospective clinical trials, including trials of immune checkpoint inhibitors in patients with thymic cancers.

Differential Dermatologic Adverse Events Associated With Checkpoint Inhibitor Monotherapy and Combination Therapy: A Meta-Analysis of Randomized Control Trials

Background: As immune checkpoint inhibitors (ICIs) transition to the forefront of cancer treatment, a better understanding of immune related adverse events (IRAEs) is essential to promote safe clinical practice. Dermatologic adverse events are the most common IRAEs and can lead to drug withdrawal and decreased quality of life. This meta-analysis aimed to investigate the risk of the most prevalent dermatologic adverse events (pruritus and rash) among various ICI treatment regimens.

Methods: A systematic search of electronic databases was performed to identify qualified randomized controlled trials (RCTs). Data for any grade and high grade pruritus and rash were extracted for meta-analysis. Two reviewers independently assessed methodological quality. The relative risk summary and 95% confidence interval were calculated.

Results: 50 RCTs involving 29941 patients were analyzed. The risk of pruritus (2.15 and 4.21 relative risk respectively) and rash (1.61 and 3.89 relative risk respectively) developing from CTLA-4 or PD-1/-L1 inhibitor were increased compared to placebo, but this effect was not dose-dependent. PD-1/-L1 plus CTLA-4 inhibitor was associated with increased risk of pruritus (1.76 and 0.98 relative risk respectively) and rash (1.72 and 1.37 relative risk respectively) compared to either monotherapy. Compared with CTLA-4 inhibitor, PD-1/-L1 inhibitor had a significantly decreased risk of pruritus and rash in both monotherapy and combination therapy (0.65 and 0.29 relative risk respectively). No significant difference was found between PD-1/-L1 inhibitor combined with chemotherapy and PD-1/-L1 monotherapy in any grade and high grade rash (0.84 and 1.43 relative risk respectively). In subgroup analyses, PD-1 inhibitor was associated with reduced risk of pruritus and rash compared to PD-L1 inhibitor.

Conclusion: Our meta-analysis demonstrates a better safety profile for PD-1/-L1 inhibitor compared to CTLA-4 inhibitor in terms of pruritus and rash among both monotherapy and multiple combination therapies. PD-L1 inhibitor may contribute to an increased risk of pruritus and rash compared to PD-1 inhibitor.

Metal- and metalloid-based compounds to target and reverse cancer multidrug resistance

Drug resistance remains the major cause of cancer treatment failure especially at the late stage of the disease. However, based on their versatile chemistry, metal and metalloid compounds offer the possibility to design fine-tuned drugs to circumvent and even specifically target drug-resistant cancer cells. Based on the paramount importance of platinum drugs in the clinics, two main areas of drug resistance reversal strategies exist: overcoming resistance to platinum drugs as well as multidrug resistance based on ABC efflux pumps. The current review provides an overview of both aspects of drug design and discusses the open questions in the field. The areas of drug resistance covered in this article involve: 1) Altered expression of proteins involved in metal uptake, efflux or intracellular distribution, 2) Enhanced drug efflux via ABC transporters, 3) Altered metabolism in drug-resistant cancer cells, 4) Altered thiol or redox homeostasis, 5) Altered DNA damage recognition and enhanced DNA damage repair, 6) Impaired induction of apoptosis and 7) Altered interaction with the immune system. This review represents the first collection of metal (including platinum, ruthenium, iridium, gold, and copper) and metalloid drugs (e.g. arsenic and selenium) which demonstrated drug resistance reversal activity. A special focus is on compounds characterized by collateral sensitivity of ABC transporter-overexpressing cancer cells. Through this approach, we wish to draw the attention to open research questions in the field. Future investigations are warranted to obtain more insights into the mechanisms of action of the most potent compounds which target specific modalities of drug resistance.

THADA drives Golgi residency and upregulation of PD-L1 in cancer cells and provides promising target for immunotherapy

Background

The abnormal upregulation of programmed death-ligand 1 (PD-L1) in cancer cells inhibits T cell-mediated cytotoxicity, but the molecular mechanisms that drive and maintain PD-L1 expression are still incompletely understood.

Methods

Combined analyses of genomes and proteomics were applied to find potential regulators of PD-L1. In vitro experiments were performed to investigate the regulatory mechanism of PD-L1 by thyroid adenoma associated gene (THADA) using human colorectal cancer (CRC) cells. The prevalence of THADA was analyzed using CRC tissue microarrays by immunohistochemistry. T cell killing assay, programmed cell death 1 binding assay and MC38 transplanted tumor models in C57BL/6 mice were developed to investigate the antitumor effect of THADA.

Results

THADA is critically required for the Golgi residency of PD-L1, and this non-redundant, coat protein complex II (COPII)-associated mechanism maintains PD-L1 expression in tumor cells. THADA mediated the interaction between PD-L1 as a cargo protein with SEC24A, a module on the COPII trafficking vesicle. Silencing THADA caused absence and endoplasmic reticulum (ER) retention of PD-L1 but not major histocompatibility complex-I, inducing PD-L1 clearance through ER-associated degradation. Targeting THADA substantially enhanced T cell-mediated cytotoxicity, and increased CD8+ T cells infiltration in mouse tumor tissues. Analysis on clinical tissue samples supported a potential role of THADA in upregulating PD-L1 expression in cancer.

Conclusions

Our data reveal a crucial cellular process for PD-L1 maturation and maintenance in tumor cells, and highlight THADA as a promising target for overcoming PD-L1-dependent immune evasion.

The Role of Mathematical Models in Immuno-Oncology: Challenges and Future Perspectives

Immuno-oncology (IO) focuses on the ability of the immune system to detect and eliminate cancer cells. Since the approval of the first immune checkpoint inhibitor, immunotherapies have become a major player in oncology treatment and, in 2021, represented the highest number of approved drugs in the field. In spite of this, there is still a fraction of patients that do not respond to these therapies and develop resistance mechanisms. In this sense, mathematical models offer an opportunity to identify predictive biomarkers, optimal dosing schedules and rational combinations to maximize clinical response. This work aims to outline the main therapeutic targets in IO and to provide a description of the different mathematical approaches (top-down, middle-out, and bottom-up) integrating the cancer immunity cycle with immunotherapeutic agents in clinical scenarios. Among the different strategies, middle-out models, which combine both theoretical and evidence-based description of tumor growth and immunological cell-type dynamics, represent an optimal framework to evaluate new IO strategies.

The Mechanism of Stimulating and Mobilizing the Immune System Enhancing the Anti-Tumor Immunity

Cancer immunotherapy is a kind of therapy that can control and eliminate tumors by restarting and maintaining the tumor-immune cycle and restoring the body's normal anti-tumor immune response. Although immunotherapy has great potential, it is currently only applicable to patients with certain types of tumors, such as melanoma, lung cancer, and cancer with high mutation load and microsatellite instability, and even in these types of tumors, immunotherapy is not effective for all patients. In order to enhance the effectiveness of tumor immunotherapy, this article reviews the research progress of tumor microenvironment immunotherapy, and studies the mechanism of stimulating and mobilizing immune system to enhance anti-tumor immunity. In this review, we focused on immunotherapy against tumor microenvironment (TME) and discussed the important research progress. TME is the environment for the survival and development of tumor cells, which is composed of cell components and non-cell components; immunotherapy for TME by stimulating or mobilizing the immune system of the body, enhancing the anti-tumor immunity. The checkpoint inhibitors can effectively block the inhibitory immunoregulation, indirectly strengthen the anti-tumor immune response and improve the effect of immunotherapy. We also found the checkpoint inhibitors have brought great changes to the treatment model of advanced tumors, but the clinical treatment results show great individual differences. Based on the close attention to the future development trend of immunotherapy, this study summarized the latest progress of immunotherapy and pointed out a new direction. To study the mechanism of stimulating and mobilizing the immune system to enhance anti-tumor immunity can provide new opportunities for cancer treatment, expand the clinical application scope and effective population of cancer immunotherapy, and improve the survival rate of cancer patients.

Pathogenesis and therapeutic strategy in platinum resistance lung cancer

Platinum compounds (cisplatin and carboplatin) represent the most active anticancer agents in clinical use both of lung cancer in mono-and combination therapies. However, platinum resistance limits its clinical application. It is necessary to understand the molecular mechanism of platinum resistance, identify predictive markers, and develop newer, more effective and less toxic agents to treat platinum resistance in lung cancer. Here, it summarizes the main molecular mechanisms associated with platinum resistance in lung cancer and the development of new approaches to tackle this clinically relevant problem. Moreover, it could lead to the development of more effective treatment for refractory lung cancer in future.

ShRNA-mediated silencing of PD-1 augments the efficacy of chimeric antigen receptor T cells on subcutaneous prostate and leukemia xenograft

Chimeric antigen receptor T cells (CAR-T) immunotherapy has shown promising clinical results in the treatment of leukemia and lymphoma, but the effectiveness is limited for solid tumors. The PD-1/PD-L1 pathway is a key immunosuppressive mechanism for cancer cells to avoid eradication by CAR-T cells. In this study, the shRNA (short hair RNA) gene-silencing technique was used to construct the third-generation of CAR-T cells with PD-1 silencing which targeted CD19 antigen (CD19/△PD-1 CAR-T) and prostate stem cell antigen (PSCA/△PD-1 CAR-T), thereby blocking the PD-1/PD-L1 pathway in treatment of lymphoma and prostate subcutaneous xenograft and enhancing the anti-tumor effect of CAR-T cells. The cell experiments showed that PD-1 silencing in CAR-T cells effectively blocked the PD-1 / PD-L1 pathway. When the ratio of effector to target cell is 8:1, △PD-1 CAR-T cells exhibited higher killing ability and cytokine releasing ability than normal CAR-T cells did. The subcutaneous tumor models were constructed using human chronic myelogenous leukemia cells expressing CD19 (K562-CD19) and human prostate cancer cells expressing PSCA (PC3-PSCA), and treated with CD19/△PD-1 CAR-T and PSCA/△PD-1 CAR-T cells, respectively. The tumor volumes significantly reduced within one week, indicating the good tumor growth inhibitory effect of △PD-1 CAR-T cells. Mice injected with △PD-1 CAR-T cells showed a significantly prolonged survival time compared to those with normal CAR-T cells. This study proved that shRNA-mediated PD-1 silencing technology is an effective strategy for blocking the PD-1/PD-L1 immunosuppression pathway and enhancing the therapeutic effect of CAR-T cells on subcutaneous xenograft. SUMMARY: The effect of CAR-T in treating solid tumors has not been as successful as that in hematological malignancies. The key immunosuppressive mechanism is the expression of PD-1/PD-L1. We used gene silencing technique mediated by shRNA (short hair RNA) to block the PD-1/PD-L1 pathway in lymphoma and prostate tumors, thus enhancing the anti-tumor effect of CAR-T cells on subcutaneous xenograft.

Combinatory Delivery of Etoposide and siCD47 in a Lipid Polymer Hybrid Delays Lung Tumor Growth in an Experimental Melanoma Lung Metastatic Model

This study investigated the feasibility of lipid polymer hybrid nanoparticles (LPH) as a platform for the combinatorial delivery of small interfering RNA (siRNA) and etoposide (Eto). Different Eto loaded LPH formulations (LPH _Eto ) are prepared. The optimized cationic LPH _Eto  with a particle size of 109.66 ± 5.17 nm and Eto entrapment efficiency (EE %) of 80.33 ± 2.55 is used to incorporate siRNA targeting CD47 (siCD47), a do not eat me marker on the surface of cancer cells. The siRNA-encapsulating LPH (LPH _siNEG-Eto ) has a particle size of 115.9 ± 4.11 nm and siRNA EE % of 63.54 ± 4.36 %. LPHs improved the cellular uptake of siRNA in a dose- and concentration-dependent manner. Enhanced cytotoxicity (3.8-fold higher than Eto solution) and high siRNA transfection efficiency (≈50 %) are obtained. An in vivo biodistribution study  showed a preferential uptake of the nanosystem into lung, liver, and spleen. In an experimental pseudo-metastatic B16F10 lung tumor model, a superior therapeutic outcome can be observed in mice treated with combinatory therapy. Immunological studies revealed elevated CD4+, CD8+ cells, and macrophages in the lung following combinatory treatment. The study suggests the potential of the current system for combinatory chemotherapy and immunotherapy for the treatment of lung cancer or lung metastasis.

Emerging role of autophagy in anti-tumor immunity: Implications for the modulation of immunotherapy resistance

Immunotherapies such as CAR-T cell transfer and antibody-targeted therapy have produced promising clinical outcomes in patients with advanced and metastatic cancer that are resistant to conventional therapies. However, with increasing use of cancer immunotherapy in clinical treatment, multiple therapy-resistance mechanisms have gradually emerged. The tumor microenvironment (TME), an integral component of cancer, can significantly influence the therapeutic response. Thus, it is worth exploring the potential of TME in modulating therapy resistance, in the hope to devise novel strategies to reinforcing anti-cancer treatments such as immunotherapy. As a crucial recycling process in the complex TME, the role of autophagy in tumor immunity has been increasingly appreciated. Firstly, autophagy in tumor cells can affect their immune response through modulating MHC-I-antigen complexes, thus modulating immunogenic tumor cell death, changing functions of immune cells via secretory autophagy, reducing the NK- and CTL-mediated cell lysis and degradation of immune checkpoint proteins. Secondly, autophagy is critical for the differentiation, maturation and survival of immune cells in the TME and can significantly affect the immune function of these cells, thereby regulating the anti-tumor immune response. Thirdly, alteration of autophagic activity in stromal cells, especially in fibroblasts, can reconstruct the three-dimensional stromal environment and metabolic reprogramming in the TME. A number of studies have demonstrated that optimal induction or inhibition of autophagy may lead to effective therapeutic regimens when combined with immunotherapy. This review discusses the important roles of autophagy in tumor cells, immune cells and stromal cells in the context of tumor immunity, and the potential of combining the autophagy-based therapy with immunotherapy as novel therapeutic approaches against cancer.