De-Risking Immunotherapy: Report of a Consensus Workshop of the Cancer Immunotherapy Consortium of the Cancer Research Institute

Identification of CD8 T-cell dysfunction associated with symptoms in myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) and Long COVID and treatment with a nebulized antioxidant/anti-pathogen agent in a retrospective case series

Background

Patients with post-acute sequelae of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection (PASC, i.e., Long COVID) have a symptom complex highly analogous to many features of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), suggesting they may share some aspects of pathogenesis in these similar disorders. ME/CFS is a complex disease affecting numerous organ systems and biological processes and is often preceded by an infection-like episode. It is postulated that the chronic manifestations of illness may result from an altered host response to infection or inability to resolve inflammation, as is being reported in Long COVID. The immunopathogenesis of both disorders is still poorly understood. Here, we show data that suggest Long COVID and ME/CFS may be due to an aberrant response to an immunological trigger-like infection, resulting in a dysregulated immune system with CD8 T-cell dysfunction reminiscent of some aspects of T-cell clonal exhaustion, a phenomenon associated with oxidative stress. As there is an urgent need for diagnostic tools and treatment strategies for these two related disabling disorders, here, in a retrospective case series, we have also identified a potential nebulized antioxidant/anti-pathogen treatment that has evidence of a good safety profile. This nebulized agent is comprised of five ingredients previously reported individually to relieve oxidative stress, attenuate NF-κB signaling, and/or to act directly to inhibit pathogens, including viruses. Administration of this treatment by nebulizer results in rapid access of small doses of well-studied antioxidants and agents with anti-pathogen potential to the lungs; components of this nebulized agent are also likely to be distributed systemically, with potential to enter the central nervous system.

Methods

and Findings: We conducted an analysis of CD8 T-cell function and severity of symptoms by self-report questionnaires in ME/CFS, Long COVID and healthy controls. We developed a CD8 T-cell functional assay, assessing CD8 T-cell dysfunction by intracellular cytokine staining (ICS) in a group of ME/CFS (n = 12) and Long COVID patients (n = 8), comparing to healthy controls (HC) with similar age and sex (n = 10). Magnet-enriched fresh CD8 T-cells in both patient groups had a significantly diminished capacity to produce both cytokines, IFNγ or TNFα, after PMA stimulation when compared to HC. The symptom severity questionnaire showed similar symptom profiles for the two disorders. Fortuitously, through a retrospective case series, we were able to examine the ICS and questionnaire data of 4 ME/CFS and 4 Long COVID patients in conjunction with their treatment (3-15 months). In parallel with the treatment pursued electively by participants in this retrospective case series, there was an increase in CD8 T-cell IFNγ and TNFα production and a decrease in overall self-reported symptom severity score by 54%. No serious treatment-associated side effects or laboratory anomalies were noted in these patients.

Conclusions

Here, in this small study, we present two observations that appear potentially fundamental to the pathogenesis and treatment of Long COVID and ME/CFS. The first is that both disorders appear to be characterized by dysfunctional CD8 T-cells with severe deficiencies in their abilities to produce IFNγ and TNFα. The second is that in a small retrospective Long COVID and ME/CFS case series, this immune dysfunction and patient health improved in parallel with treatment with an immunomodulatory, antioxidant pharmacological treatment with anticipated anti-pathogen activity. This work provides evidence of the potential utility of a biomarker, CD8 T-cell dysfunction, and suggests the potential for benefit from a new nebulized antioxidant/anti-pathogen treatment. These immune biomarker data may help build capacity for improved diagnosis and tracking of treatment outcomes during clinical trials for both Long COVID and ME/CFS while providing clues to new treatment avenues that suggest potential efficacy for both conditions.

Harnessing 3D in vitro systems to model immune responses to solid tumours: a step towards improving and creating personalized immunotherapies

In vitro 3D models are advanced biological tools that have been established to overcome the shortcomings of oversimplified 2D cultures and mouse models. Various in vitro 3D immuno-oncology models have been developed to mimic and recapitulate the cancer-immunity cycle, evaluate immunotherapy regimens, and explore options for optimizing current immunotherapies, including for individual patient tumours. Here, we review recent developments in this field. We focus, first, on the limitations of existing immunotherapies for solid tumours, secondly, on how in vitro 3D immuno-oncology models are established using various technologies - including scaffolds, organoids, microfluidics and 3D bioprinting - and thirdly, on the applications of these 3D models for comprehending the cancer-immunity cycle as well as for assessing and improving immunotherapies for solid tumours.

Transgenic viral expression of PH-20, IL-12, and sPD1-Fc enhances immune cell infiltration and anti-tumor efficacy of an oncolytic virus

Oncolytic viruses are of significant clinical interest due to their ability to directly infect and kill tumors and enhance the anti-tumor immune response. Previously, we developed KLS-3010, a novel oncolytic virus derived from the International Health Department-White (IHD-W) strain vaccinia virus, which has robust tumoricidal effects. In the present study, we generated a recombinant oncolytic virus, KLS-3020, by inserting three transgenes (hyaluronidase [PH-20], interleukin-12 [IL-12], and soluble programmed cell death 1 fused to the Fc domain [sPD1-Fc]) into KLS-3010 and investigated its anti-tumor efficacy and ability to induce anti-tumor immune responses in CT26.WT and B16F10 mouse tumor models. A single injection of KLS-3020 significantly decreased tumor growth. The roles of the transgenes were investigated using viruses expressing each single transgene alone and KLS-3020. PH-20 promoted virus spread and tumor immune cell infiltration, IL-12 activated and reprogrammed T cells to inflammatory phenotypes, and sPD1-Fc increased intra-tumoral populations of activated T cells. The tumor-specific systemic immune response and the abscopal tumor control elicited by KLS-3020 were demonstrated in the CT26.WT tumor model. The insertion of transgenes into KLS-3020 increased its anti-tumor efficacy, supporting further clinical investigation of KLS-3020 as a novel oncolytic immunotherapy.

Conformation specific antagonistic high affinity antibodies to the RON receptor kinase for imaging and therapy

The RON receptor tyrosine kinase is an exceptionally interesting target in oncology and immunology. It is not only overexpressed in a wide variety of tumors but also has been shown to be expressed on myeloid cells associated with tumor infiltration, where it serves to dampen tumour immune responses and reduce the efficacy of anti-CTLA4 therapy. Potent and selective inhibitory antibodies to RON might therefore both inhibit tumor cell growth and stimulate immune rejection of tumors. We derived cloned and sequenced a new panel of exceptionally avid anti-RON antibodies with picomolar binding affinities that inhibit MSP-induced RON signaling and show remarkable potency in antibody dependent cellular cytotoxicity. Antibody specificity was validated by cloning the antibody genes and creating recombinant antibodies and by the use of RON knock out cell lines. When radiolabeled with 89-Zirconium, the new antibodies 3F8 and 10G1 allow effective immuno-positron emission tomography (immunoPET) imaging of RON-expressing tumors and recognize universally exposed RON epitopes at the cell surface. The 10G1 was further developed into a novel bispecific T cell engager with a 15 pM EC50 in cytotoxic T cell killing assays.

mRNA-Based Approaches to Treating Liver Diseases

Diseases that affect the liver account for approximately 2 million deaths worldwide each year. The increasing prevalence of these diseases and the limited efficacy of current treatments are expected to stimulate substantial growth in the global market for therapeutics that target the liver. Currently, liver transplantation is the only curative option available for many liver diseases. Gene therapy represents a valuable approach to treatment. The liver plays a central role in a myriad of essential metabolic functions, making it an attractive organ for gene therapy; hepatocytes comprise the most relevant target. To date, viral vectors constitute the preferred approach to targeting hepatocytes with genes of therapeutic interest. Alternatively, mRNA-based therapy offers a number of comparative advantages. Clinical and preclinical studies undertaken to treat inherited metabolic diseases affecting the liver, cirrhosis and fibrosis, hepatocellular carcinoma, hepatitis B, and cytomegalovirus using lipid nanoparticle-encapsulated mRNAs that encode the therapeutic or antigenic protein of interest are discussed.

Dual near-infrared II laser modulates the cellular redox state of T cells and augments the efficacy of cancer immunotherapy

Immunotherapy, including immune checkpoint inhibitors, has revolutionized cancer treatment, but only a minor fraction of patients shows durable responses. A new approach to overcome this limitation is yet to be identified. Recently, we have shown that photobiomodulation (PBM) with near-infrared (NIR) light in the NIR-II window reduces oxidative stress and supports the proliferation of CD8+ T cells, suggesting that PBM with NIR-II light could augment anti-cancer immunity. Here, we report a novel approach to support tumor-infiltrating CD8+ T cells upon PBM with NIR-II laser with high tissue penetration depth. Brief treatments of a murine model of breast cancer with dual 1064 and 1270 nm lasers reduced the expression of the programmed cell death protein 1 (PD-1) in CD8+ T cells in a syngeneic mouse model of breast cancer. The direct effect of the NIR-II laser treatment on T cells was confirmed by the enhanced tumor growth delay by the adoptive transfer of laser-treated CD8+ T cells ex vivo against a model tumor antigen. We further demonstrated that specific NIR-II laser parameters augmented the effect of the immune checkpoint inhibitor on tumor growth. PBM with NIR-II light augments the efficacy of cancer immunotherapy by supporting CD8+ T cells. Unlike the current immunotherapy with risks of undesirable drug-drug interactions and severe adverse events, the laser is safe and low-cost. It can be broadly combined with other therapy without modification to achieve clinical significance. In addition, our study established a path to develop a novel laser-based therapy to treat cancer effectively.

Cancer vaccines: the next immunotherapy frontier

After several decades, therapeutic cancer vaccines now show signs of efficacy and potential to help patients resistant to other standard-of-care immunotherapies, but they have yet to realize their full potential and expand the oncologic armamentarium. Here, we classify cancer vaccines by what is known of the included antigens, which tumors express those antigens and where the antigens colocalize with antigen-presenting cells, thus delineating predefined vaccines (shared or personalized) and anonymous vaccines (ex vivo or in situ). To expedite clinical development, we highlight the need for accurate immune monitoring of early trials to acknowledge failures and advance the most promising vaccines.

Top 10 Challenges in Cancer Immunotherapy

Cancer immunotherapy is a validated and critically important approach for treating patients with cancer. Given the vast research and clinical investigation efforts dedicated to advancing both endogenous and synthetic immunotherapy approaches, there is a need to focus on crucial questions and define roadblocks to the basic understanding and clinical progress. Here, we define ten key challenges facing cancer immunotherapy, which range from lack of confidence in translating pre-clinical findings to identifying optimal combinations of immune-based therapies for any given patient. Addressing these challenges will require the combined efforts of basic researchers and clinicians, and the focusing of resources to accelerate understanding of the complex interactions between cancer and the immune system and the development of improved treatment options for patients with cancer.

Conceptual Development of Immunotherapeutic Approaches to Gastrointestinal Cancer

Gastrointestinal (GI) cancer is one of the common causes of cancer-related death worldwide. Chemotherapy and/or immunotherapy are the current treatments, but some patients do not derive clinical benefits. Recently, studies from cancer molecular subtyping have revealed that tumor molecular biomarkers may predict the immunotherapeutic response of GI cancer patients. However, the therapeutic response of patients selected by the predictive biomarkers is suboptimal. The tumor immune-microenvironment apparently plays a key role in modulating these molecular-determinant predictive biomarkers. Therefore, an understanding of the development and recent advances in immunotherapeutic pharmacological intervention targeting tumor immune-microenvironments and their potential predictive biomarkers will be helpful to strengthen patient immunotherapeutic efficacy. The current review focuses on an understanding of how the host-microenvironment interactions and the predictive biomarkers can determine the efficacy of immune checkpoint inhibitors. The contribution of environmental pathogens and host immunity to GI cancer is summarized. A discussion regarding the clinical evidence of predictive biomarkers for clinical trial therapy design, current immunotherapeutic strategies, and the outcomes to GI cancer patients are highlighted. An understanding of the underlying mechanism can predict the immunotherapeutic efficacy and facilitate the future development of personalized therapeutic strategies targeting GI cancers.

High numbers of activated helper T cells are associated with better clinical outcome in early stage vulvar cancer, irrespective of HPV or p53 status

Background

Vulvar squamous cell carcinoma (VSCC) has been suggested to consist of three subtypes; HPV-positive, HPV-negative mutated TP53 or HPV-negative TP53 wildtype, with different clinical courses. To analyze the immune infiltrate in these molecular subtypes and its impact on clinical outcome, an in-depth study of the tumor immune microenvironment was performed.

Methods

Sixty-five patients with invasive VSCC matched for age, FIGO stage and treatment modality, were grouped according to the presence of HPV and p53 protein expression status. Archived tissues were analyzed for intraepithelial and stromal expression of CD3, CD8, Foxp3, PD-1, and pan-keratin in randomly selected areas using immunofluorescence. Additional phenotyping of T cells was performed ex-vivo on VSCC (n = 14) and blood samples by flow cytometry. Healthy vulvar samples and blood served as controls.

Results

Based on T-cell infiltration patterns about half of the VSCC were classified as inflamed or altered-excluded while one-third was immune-deserted. High intraepithelial helper T cell infiltration was observed in 78% of the HPV-induced VSCC, 60% of the HPVnegVSCC/p53wildtype and 40% of the HPVnegVSCC with abnormal p53 expression. A high intraepithelial infiltration with activated (CD3⁺PD-1⁺), specifically helper T cells (CD3⁺CD8⁻Foxp3⁻), was associated with a longer recurrence-free period and overall survival, irrespective of HPV and p53 status. Flow cytometry confirmed the tumor-specific presence of activated (CD4⁺PD-1⁺⁺CD161⁻CD38⁺HLA-DR⁺ and CD8⁺CD103⁺CD161⁻NKG2A^+/−PD1⁺⁺CD38⁺⁺HLA-DR⁺) effector memory T cells.

Conclusion

This is the first study demonstrating an association between intraepithelial T cells and clinical outcome in VSCC. Our data suggest that abnormal p53 expressing VSCCs mostly are cold tumors whereas HPV-driven VSCCs are strongly T-cell infiltrated.

Electronic supplementary material

The online version of this article (10.1186/s40425-019-0712-z) contains supplementary material, which is available to authorized users.

Randomized-controlled phase II trial of salvage chemotherapy after immunization with a TP53-transfected dendritic cell-based vaccine (Ad.p53-DC) in patients with recurrent small cell lung cancer

Small cell lung cancer TP53 mutations lead to expression of tumor antigens that elicits specific cytotoxic T-cell immune responses. In this phase II study, dendritic cells transfected with wild-type TP53 (vaccine) were administered to patients with extensive-stage small cell lung cancer after chemotherapy. Patients were randomized 1:1:1 to arm A (observation), arm B (vaccine alone), or arm C (vaccine plus all-trans-retinoic acid). Vaccine was administered every 2 weeks (3 times), and all patients were to receive paclitaxel at progression. Our primary endpoint was overall response rate (ORR) to paclitaxel. The study was not designed to detect overall response rate differences between arms. Of 69 patients enrolled (performance status 0/1, median age 62 years), 55 were treated in stage 1 (18 in arm A, 20 in arm B, and 17 in arm C) and 14 in stage 2 (arm C only), per 2-stage Simon Minimax design. The vaccine was safe, with mostly grade 1/2 toxicities, although 1 arm-B patient experienced grade 3 fatigue and 8 arm-C patients experienced grade 3 toxicities. Positive immune responses were obtained in 20% of arm B (95% confidence interval [CI], 5.3-48.6) and 43.3% of arm C (95% CI 23.9-65.1). The ORRs to the second-line chemotherapy (including paclitaxel) were 15.4% (95% CI 2.7-46.3), 16.7% (95% CI 2.9-49.1), and 23.8% (95% CI 9.1-47.5) for arms A, B, and C, with no survival differences between arms. Although our vaccine failed to improve ORRs to the second-line chemotherapy, its safety profile and therapeutic immune potential remain. Combinations with the other immunotherapeutic agents are reasonable options.

Cancer Immunotherapy: Beyond Checkpoint Blockade

Blocking antibodies to the immune checkpoint receptors or their ligands have revolutionized the treatment of diverse malignancies. Many tumors are recognized by adaptive immunity, but these adaptive responses can be inhibited by immunosuppressive mechanisms within the tumor, often through pathways outside of the currently targeted checkpoints. For this reason, only a minority of cancer patients achieve durable responses to current immunotherapies. Multiple novel approaches strive to expand immunotherapy's reach. These may include targeting alternative immune checkpoints. However, many investigational strategies look beyond checkpoint blockade. These include cellular therapies to bypass endogenous immunity and efforts to stimulate new adaptive antitumor responses using vaccines, adjuvants, and combinations with cytotoxic therapy, as well as strategies to inhibit innate immune suppression and modulate metabolism within the tumor microenvironment. The challenge for immunotherapy going forward will be to select rational strategies for overcoming barriers to effective antitumor responses from the myriad possible targets.

Making cold malignant pleural effusions hot: driving novel immunotherapies

Malignant pleural effusions, arising from either primary mesotheliomas or secondary malignancies, heralds advanced disease and poor prognosis. Current treatments, including therapeutic thoracentesis and tube thoracostomy, are largely palliative. The immunosuppressive environment within the pleural cavity includes myeloid derived suppressor cells, T-regulatory cells, and dysfunctional T cells. The advent of effective immunotherapy with checkpoint inhibitors and adoptive cell therapies for lung cancer and other malignancies suggests a renewed examination of local and systemic therapies for this malady. Prior strategies reporting remarkable success, including instillation of the cytokine interleukin-2, perhaps coupled with checkpoint inhibitors, should be further evaluated in the modern era.

Global microarray profiling identified hsa_circ_0064428 as a potential immune-associated prognosis biomarker for hepatocellular carcinoma

BACKGROUND

Increasing evidence has shown that circular RNAs (circRNAs) are involved tumourigenesis and metastasis of hepatocellular carcinoma (HCC); however, progression about its function in HCC is relatively slow. Here, we aimed to investigate whether plasma circRNAs could reflect the tumour-infiltrating lymphocytes (TILs) in HCC tumour tissues and serve as prognosis biomarker for HCC.

METHODS

Tissue samples of patients with HCC were subjected to immunohistochemistry staining against CD8 to examine the TILs. Then, we investigated the expression profile of circRNAs by microarray between plasma of patients with HCC with high TILs and low TILs, and the differentially expressed circRNAs were validated with qRT-PCR. Statistical analysis was performed with SPSS software and GraphPad Prism.

RESULTS

We have demonstrated that patients with HCC with high TILs exhibit a significant better overall survival, suggesting clinical outcome could be predicted by TILs. Global circRNA microarray between plasma of patients with HCC with high TILs and low TILs successfully identified six differentially expressed novel circRNAs. Among them, the expression of hsa_circ_0064428 was significantly reduced in patients with HCC with high TILs but increased in patients with low TILs. Moreover, hsa_circ_0064428 was negatively correlated with patient's survival, tumour size and metastasis.

CONCLUSION

These findings together imply that hsa_circ_0064428 could be considered as a potential HCC prognosis biomarker. Future in-depth research is required to further illustrate the involvement of hsa_circ_0064428 in HCC tumourigenesis and metastasis.

IL-10 expression defines an immunosuppressive dendritic cell population induced by antitumor therapeutic vaccination

Vaccination induces immunostimulatory signals that are often accompanied by regulatory mechanisms such as IL-10, which control T-cell activation and inhibit vaccine-dependent antitumor therapeutic effect. Here we characterized IL-10-producing cells in different tumor models treated with therapeutic vaccines. Although several cell subsets produced IL-10 irrespective of treatment, an early vaccine-dependent induction of IL-10 was detected in dendritic cells (DC). IL-10 production defined a DC population characterized by a poorly mature phenotype, lower expression of T-cell stimulating molecules and upregulation of PD-L1. These IL-10⁺ DC showed impaired in vitro T-cell stimulatory capacity, which was rescued by incubation with IL-10R and PD-L1-inhibiting antibodies. In vivo IL-10 blockade during vaccination decreased the proportion of IL-10⁺ DC and improved their maturation, without modifying PD-L1 expression. Similarly, PD-L1 blockade did not affect IL- 10 expression. Interestingly, vaccination combined with simultaneous blockade of IL-10 and PD-L1 induced stronger immune responses, resulting in a higher therapeutic efficacy in tumor-bearing mice. These results show that vaccine-induced immunoregulatory IL- 10⁺ DC impair priming of antitumor immunity, suggesting that therapeutic vaccination protocols may benefit from combined targeting of inhibitory molecules expressed by this DC subset.

Cancer Immunotherapy Trials Underutilize Immune Response Monitoring

Immune-related radiological and biomarker monitoring in cancer immunotherapy trials permits interrogation of efficacy and reasons for therapeutic failure. We report the results from a cross-sectional analysis of response monitoring in 685 T-cell checkpoint-targeted cancer immunotherapy trials in solid malignancies, as registered on the U.S. National Institutes of Health trial registry by October 2016. Immune-related radiological response criteria were registered for only 25% of clinical trials. Only 38% of trials registered an exploratory immunological biomarker, and registration of immunological biomarkers has decreased over the last 15 years. We suggest that increasing the utilization of immune-related response monitoring across cancer immunotherapy trials will improve analysis of outcomes and facilitate translational efforts to extend the benefit of immunotherapy to a greater proportion of patients with cancer.

Current and future immunotherapies for thyroid cancer

INTRODUCTION

Cancer immunotherapies were approved in recent years, including immune checkpoint inhibitors. Experience with ipilimumab (CTLA-4 antagonist), nivolumab and pembrolizumab (PD-1 antagonists), and atezolizumab (PD-L1 antagonist) has shown that the impact on overall survival in cancer patients is paramount. Immune checkpoint inhibitors target the immune system and they can be applied across multiple cancers; the response rate is ranging from 20 to 40%. Many studies have shown that thyroid cancer (TC) cells produce cytokines and chemokines, inducing several tumor-promoting effects. Targeting and/or lowering cytokines and chemokines concentrations within the tumor microenvironment would produce a therapeutic benefit. In TC, increased Treg and PD-1⁺ T cell frequencies are indicative of aggressive disease and PD-L1 expression correlates with a greater risk of recurrence. Area covered: After performing a literature search, a few pioneering studies have evaluated immunotherapy in thyroid cancer. More recently a case has been described involving anaplastic thyroid cancer treated with vemurafenib and nivolumab, with substantial regression and complete radiographic and clinical remission. Expert commentary: The use of immune checkpoint inhibitors in aggressive TC has not yet been extensively investigated and further studies in a large number of TC patients are urgently needed.

Urgent Need to Define Pretreatment Predictors of Immune Check Point Inhibitors Related Endocrinopathies: A Case Report and Review of Literature

Immune check point inhibitors have revolutionized the treatment of metastatic malignancies. They are a promising area in oncology and more drugs are likely to be available in the coming years. Along with the promise of better response oncologically, there is an increased incidence of endocrinopathies related to autoimmunity. This case report illustrates the dramatic development of hypothyroidism in a patient with underlying subclinical hyperthyroidism. It also suggests the potential pretreatment predictors of endocrinopathies related to these immune check point inhibitors.

Inflammation-induced IgA+ cells dismantle anti-liver cancer immunity

The role of adaptive immunity in early cancer development is controversial. Here we show that chronic inflammation and fibrosis in humans and mice with non-alcoholic fatty liver disease is accompanied by accumulation of liver-resident immunoglobulin-A-producing (IgA⁺) cells. These cells also express programmed death ligand 1 (PD-L1) and interleukin-10, and directly suppress liver cytotoxic CD8⁺ T lymphocytes, which prevent emergence of hepatocellular carcinoma and express a limited repertoire of T-cell receptors against tumour-associated antigens. Whereas CD8⁺ T-cell ablation accelerates hepatocellular carcinoma, genetic or pharmacological interference with IgA⁺ cell generation attenuates liver carcinogenesis and induces cytotoxic T-lymphocyte-mediated regression of established hepatocellular carcinoma. These findings establish the importance of inflammation-induced suppression of cytotoxic CD8⁺ T-lymphocyte activation as a tumour-promoting mechanism.

Current and Evolving Therapies for Metastatic Pancreatic Cancer: Are We Stuck With Cytotoxic Chemotherapy?

At present, front-line therapy for metastatic pancreatic ductal adenocarcinoma is combination chemotherapy, most commonly FOLFIRINOX (fluorouracil, irinotecan, and oxaliplatin) or gemcitabine and nanoparticle albumin-bound paclitaxel. Despite a better understanding of the genomic landscape and the importance of the tumor microenvironment, we have not made a seismic shift in the overall survival for this disease. Given our growing understanding of the biology of pancreatic ductal adenocarcinoma, the question remains whether novel, noncytotoxic agents will augment or even replace conventional chemotherapy. The thrust of ongoing efforts can be divided into broad categories, including exploiting the DNA damage repair phenotype, stroma and specific pathway-targeting agents, and enhancing immune destruction of pancreatic ductal adenocarcinoma. In this article, we review the current and evolving therapeutic landscape of metastatic pancreatic cancer.

Increasing Tumor-Infiltrating T Cells through Inhibition of CXCL12 with NOX-A12 Synergizes with PD-1 Blockade

Immune checkpoint inhibitors promote T cell-mediated killing of cancer cells; however, only a subset of patients benefit from the treatment. A possible reason for this limitation may be that the tumor microenvironment (TME) is immune privileged, which may exclude cytotoxic T cells from the vicinity of cancer cells. The chemokine CXCL12 is key to the TME-driven immune suppression. In this study, we investigated the potential of CXCL12 inhibition by use of the clinical-stage l-RNA-aptamer NOX-A12 (olaptesed pegol) to increase the number of tumor-infiltrating lymphocytes. We used heterotypic tumor-stroma spheroids that mimic a solid tumor with a CXCL12-abundant TME. NOX-A12 enhanced the infiltration of T and NK cells in a dose-dependent manner. NOX-A12 and PD-1 checkpoint inhibition synergistically activated T cells in the spheroids, indicating that the agents complement each other. The findings were validated in vivo in a syngeneic murine model of colorectal cancer in which the addition of NOX-A12 improved anti-PD-1 therapy. Taken together, our work shows that CXCL12 inhibition can break the immune-privileged status of the TME by paving the way for immune effector cells to enter into the tumor, thereby broadening the applicability of checkpoint inhibitors in cancer patients. Cancer Immunol Res; 5(11); 950-6. ©2017 AACR.

Macrophage Polarization Contributes to Glioblastoma Eradication by Combination Immunovirotherapy and Immune Checkpoint Blockade

Glioblastoma is an immunosuppressive, fatal brain cancer that contains glioblastoma stem-like cells (GSCs). Oncolytic herpes simplex virus (oHSV) selectively replicates in cancer cells while inducing anti-tumor immunity. oHSV G47Δ expressing murine IL-12 (G47Δ-mIL12), antibodies to immune checkpoints (CTLA-4, PD-1, PD-L1), or dual combinations modestly extended survival of a mouse glioma model. However, the triple combination of anti-CTLA-4, anti-PD-1, and G47Δ-mIL12 cured most mice in two glioma models. This treatment was associated with macrophage influx and M1-like polarization, along with increased T effector to T regulatory cell ratios. Immune cell depletion studies demonstrated that CD4⁺ and CD8⁺ T cells as well as macrophages are required for synergistic curative activity. This combination should be translatable to the clinic and other immunosuppressive cancers.

Orthotopic Patient-Derived Pancreatic Cancer Xenografts Engraft Into the Pancreatic Parenchyma, Metastasize, and Induce Muscle Wasting to Recapitulate the Human Disease

OBJECTIVE

Limitations associated with current animal models serve as a major obstacle to reliable preclinical evaluation of therapies in pancreatic cancer (PC). In an effort to develop more reliable preclinical models, we have recently established a subcutaneous patient-derived xenograft (PDX) model. However, critical aspects of PC responsible for its highly lethal nature, such as the development of distant metastasis and cancer cachexia, remain underrepresented in the flank PDX model. The purpose of this study was to evaluate the degree to which an orthotopic PDX model of PC recapitulates these aspects of the human disease.

METHODS

Human PDX-derived PC tumors were implanted directly into the pancreas of NOD.Cg-Prkdc Il2rg/SzJ mice. Tumor growth, metastasis, and muscle wasting were then evaluated.

RESULTS

Orthotopically implanted PDX-derived tumors consistently incorporated into the murine pancreatic parenchyma, metastasized to both the liver and lungs and induced muscle wasting directly proportional to the size of the tumor, consistent of the cancer cachexia syndrome.

CONCLUSIONS

Through the orthotopic implantation technique described, we demonstrate a highly reproducible model that recapitulates both local and systemic aspects of human PC.

Cancer Immunotherapy and Personalized Medicine: Emerging Technologies and Biomarker-Based Approaches

Purpose of review

The vision and strategy for the 21st century treatment of cancer calls for a personalized approach in which therapy selection is designed for each individual patient. While genomics has led the field of personalized cancer medicine over the past several decades by connecting patient-specific DNA mutations with kinase-targeted drugs, the recent discovery that tumors evade immune surveillance has created unique challenges to personalize cancer immunotherapy. In this mini-review we will discuss how personalized medicine has evolved recently to accommodate the emerging era of cancer immunotherapy. Moreover, we will discuss novel platform technologies that have been engineered to address some of the persisting limitations.

Recent finding

Beginning with early evidence in personalized medicine, we discuss how biomarker-driven approaches to predict clinical success have evolved to account for the heterogeneous tumor ecosystem. In the emerging field of cancer immunotherapy, this challenge requires the use of a novel set of tools, distinct from the classic approach of next-generation genomic sequencing-based strategies. We will introduce new techniques that seek to tailor immunotherapy by re-programming patient-autologous T-cells, and new technologies that are emerging to predict clinical efficacy by mapping infiltration of lymphocytes, and harnessing fully humanized platforms that reconstruct and interrogate immune checkpoint blockade, ex-vivo.

Summary

While cancer immunotherapy is now leading to durable outcomes in difficult-to-treat cancers, success is highly variable. Developing novel approaches to study cancer immunotherapy, personalize treatment to each patient, and achieve greater outcomes is penultimate to developing sustainable cures in the future. Numerous techniques are now emerging to help guide treatment decisions, which go beyond simple biomarker-driven strategies, and are now we are seeking to interrogate the entirety of the dynamic tumor ecosystem.

Evaluation of invasive breast cancer samples using a 12-chemokine gene expression score: correlation with clinical outcomes

Background

A unique 12-chemokine gene expression score (CS) accurately predicted the presence of tumor-localized, ectopic lymph node-like structures (TL-ELNs) and improved overall survival (OS) in primary colorectal cancer and metastatic melanoma. We analyzed the correlation between CS, clinicopathological variables, molecular data, and 366 survival in Moffitt Cancer Center’s Total Cancer Care (TCC) patients with non-metastatic breast cancer.

Methods

Affymetrix gene expression profiles were used to interrogate the CS by the principal component method. Breast tumors were classified as high or low score based on median split, and correlations between clinicopathologic variables, PAM50 molecular subtype, and ELN formation were analyzed using the TCC dataset. Differences in overall survival (OS) and recurrence-free survival (RFS) in the larger KM Plot breast cancer public datasets were compared using Kaplan-Meier curves.

Results

We divided the Total Cancer Care (TCC) breast cancer patients into two groups of high or low CS. Mean CS was 0.24 (range, 2.2–2.1). Patients with higher CS were more likely to be white (172 vs. 159; p = 0.03), had poorly differentiated tumors (112 vs. 59; p <0.0001), ER/PR negative (41 vs. 26) and HER2 positive (36 vs. 19; p = 0.001), and contain TL-ELNs. Higher CS scores were also seen in the basal and HER2+ molecular subtypes. In the KM Plot breast cancer datasets higher CS patients demonstrated superior OS (HR = 0.73, p = 0.008) and RFS (HR 0.76, p = <0.0001), especially in basal and HER2+ patients.

Conclusions

High CS breast tumors tend to be higher grade, basal or HER2+, and present more frequently in Caucasians. However, this group of patients also shows the presence of TL-ELNs within the tumor microenvironment and has better survival outcomes. The CS is a novel tool that can identify breast cancer patients with tumors of a unique intratumoral immune composition and better prognosis. Whether or not the CS is a predictive response marker in breast cancer patients undergoing immunotherapy remains to be determined.

Electronic supplementary material

The online version of this article (doi:10.1186/s13058-017-0864-z) contains supplementary material, which is available to authorized users.

Immunotherapy in colorectal cancer: What have we learned so far?

After decades of progress based on chemotherapy and targeted agents, patients with metastatic colorectal cancer still have low long-term survival, with more than 500,000 deaths occurring worldwide every year. Recent results showing clinical evidence of efficacy using immunotherapy in other types of tumors, such as melanoma and lung cancer, have also made this a viable therapy for evaluation in colorectal cancer in clinical trials. The development of cancer immunotherapies is progressing quickly, with a variety of technological approaches. This review summarizes the current status of clinical trials testing immunotherapy in colorectal cancer and discusses what has been learned based on previous results. Immunotherapy strategies, such as various models of vaccines, effector-cell therapy and checkpoint inhibitor antibodies, provide protection against progression for a limited subset of patients diagnosed with colorectal cancer. A better understanding of particular immune cell types and pathways in each patient is still needed. These findings will enable the development of novel biomarkers to select the appropriate subset of patients to be treated with a particular immunotherapy, and the tendencies determined from recent results can guide clinical practice for oncologists in this new therapeutic area and in the design of the next round of clinical trials.