Synergy between chemotherapeutic agents and CTLA-4 blockade in preclinical tumor models

COEXPEDIA: exploring biomedical hypotheses via co-expressions associated with medical subject headings (MeSH)

The use of high-throughput array and sequencing technologies has produced unprecedented amounts of gene expression data in central public depositories, including the Gene Expression Omnibus (GEO). The immense amount of expression data in GEO provides both vast research opportunities and data analysis challenges. Co-expression analysis of high-dimensional expression data has proven effective for the study of gene functions, and several co-expression databases have been developed. Here, we present a new co-expression database, COEXPEDIA (www.coexpedia.org), which is distinctive from other co-expression databases in three aspects: (i) it contains only co-functional co-expressions that passed a rigorous statistical assessment for functional association, (ii) the co-expressions were inferred from individual studies, each of which was designed to investigate gene functions with respect to a particular biomedical context such as a disease and (iii) the co-expressions are associated with medical subject headings (MeSH) that provide biomedical information for anatomical, disease, and chemical relevance. COEXPEDIA currently contains approximately eight million co-expressions inferred from 384 and 248 GEO series for humans and mice, respectively. We describe how these MeSH-associated co-expressions enable the identification of diseases and drugs previously unknown to be related to a gene or a gene group of interest.

Immune checkpoint and inflammation as therapeutic targets in pancreatic carcinoma

Pancreatic adenocarcinoma (PAC) is one of the most deadly malignant neoplasms, and the efficacy of conventional cytotoxic chemotherapy is far from satisfactory. Recent research studies have revealed that immunosuppression and inflammation are associated with oncogenesis, as well as tumor development, invasion, and metastasis in PAC. Thus, immunosuppression-related signaling, especially that involving immune checkpoint and inflammation, has emerged as novel treatment targets for PAC. However, PAC is an immune-resistant tumor, and it is still unclear whether immune checkpoint or anti-inflammation therapies would be an ideal strategy. In this article, we will review immune checkpoint and inflammation as potential targets, as well as clinical trials and the prospects for immunotherapy in PAC.

Immune-system-dependent anti-tumor activity of a plant-derived polyphenol rich fraction in a melanoma mouse model

Recent findings suggest that part of the anti-tumor effects of several chemotherapeutic agents require an intact immune system. This is in part due to the induction of immunogenic cell death. We have identified a gallotannin-rich fraction, obtained from Caesalpinia spinosa (P2Et) as an anti-tumor agent in both breast carcinoma and melanoma. Here, we report that P2Et treatment results in activation of caspase 3 and 9, mobilization of cytochrome c and externalization of annexin V in tumor cells, thus suggesting the induction of apoptosis. This was preceded by the onset of autophagy and the expression of immunogenic cell death markers. We further demonstrate that P2Et-treated tumor cells are highly immunogenic in vaccinated mice and induce immune system activation, clearly shown by the generation of interferon gamma (IFN-γ) producing tyrosine-related protein 2 antigen-specific CD8+ T cells. Moreover, the tumor protective effects of P2Et treatment were abolished in immunodeficient mice, and partially lost after CD4 and CD8 depletion, indicating that P2Et's anti-tumor activity is highly dependent on immune system and at least in part of T cells. Altogether, these results support the hypothesis that the gallotannin-rich fraction P2Et's anti-tumor effects are mediated to a great extent by the endogenous immune response following to the exposure to immunogenic dying tumor cells.

Evaluation of the pharmacokinetics of ixabepilone for the treatment of breast cancer

INTRODUCTION

Chemotherapeutic agents, such as anthracyclines, taxanes and fluoropyrimidines, have significantly improved the outcome of breast cancer patients. However, mechanisms of resistance limit the effectiveness of these drugs. The microtubule-stabilizing agent ixabepilone has been approved for treatment of metastatic breast cancer (MBC) patients resistant or refractory to taxanes, anthracycline and capecitabine.

AREAS COVERED

In this review, we summarized data on pharmacodynamics, pharmacokinetics, preclinical and clinical studies of ixabepilone in breast cancer. This article was compiled through searches on ixabepilone up to March 2015 in the PubMed and the clinicaltrials.gov databases; the FDA and European Medicine Agency (EMA) websites; and the ASCO and AACR proceedings.

EXPERT OPINION

Ixabepilone is a well-tolerated and effective drug in MBC at the approved dose. The most important challenges that ongoing clinical trials are still addressing are: the optimal dosing schedule that might improve the risk/benefit ratio, the clinical efficacy of ixabepilone in early breast cancer, the efficacy in triple-negative breast cancer (TNBC) patients and the identification of biomarkers predictive of response.

Immunotherapy with checkpoint inhibitors for lung cancer: novel agents, biomarkers and paradigms

Despite recent advances, prognosis of patients with advanced lung cancer remains dismal. Owing to a better understanding of the interactions between immune system and tumor cells, immunotherapy has emerged as a promising therapeutic strategy. After the recent approval of nivolumab and the promising results with other immune checkpoint inhibitors, combination strategies are now subject of intensive research. Notwithstanding these successes, immunotherapy still holds significant drawbacks. As the target shifts from tumor cells to the tumor microenvironment, treatment paradigms are changing and several improvements are needed for optimal use in clinical practice. Robust biomarkers for patient selection and a reliable way of evaluating treatment response are high priorities. Herein we review current data on immune checkpoint inhibitors for lung cancer treatment.

Chemotherapy and immunotherapy: mapping the road ahead

Cancer immunotherapy, and in particular checkpoint blockade, is now standard clinical care for a growing number of cancers. Cytotoxic drugs have been the primary weapon against cancer for a long time and have typically been understood because of their capacity to directly kill tumour cells. It is now clear that these drugs are potential partners for checkpoint blockade and different drugs can influence the immune response to cancer through a wide variety of mechanisms. Some of these relate to immunogenic cell death, whilst others relate to changes in antigen-presentation, tumour cell targeting, or depletion of immunosuppressive cells. Here, we review some recent advances in our understanding of the immunological changes associated with chemotherapy, discuss progress in combining chemotherapy with checkpoint blockade, and comment on the difficulties encountered in translating promising preclinical data into successful treatments for cancer patients.

Immune checkpoints and immunotherapy for colorectal cancer

Colorectal cancer (CRC) remains one of the major causes of death worldwide, despite steady improvement in early detection and overall survival over the past decade. Current treatment paradigms, with chemotherapy and biologics, appear to have reached their maximum benefit. Immunotherapy, especially with checkpoint inhibitors, has shown considerable clinical benefit in various cancers, including mismatch-repair-deficient CRC. This has led to the planning and initiation of several clinical trials evaluating novel immunotherapy agents—as single agents, combinations and in conjunction with chemotherapy—in patients with CRC. This article reviews biological and preclinical data for checkpoint inhibitors and discusses various immunotherapy trials in CRC, as well as current efforts in CRC immunotherapy.

Immune Checkpoint Blockade: A New Paradigm in Treating Advanced Cancer

The approval of the immune checkpoint inhibitor ipilimumab for the treatment of advanced melanoma in 2011 spearheaded the development of other anticancer therapies with immune mechanisms of action, including other immune checkpoint inhibitors. Instead of acting directly on the tumor, these therapies work to "remove the brakes" on the immune system to restore antitumor immune responses. In addition to ipilimumab, which targets the cytotoxic T lymphocyte-associated antigen 4 pathway, several new drugs that target the programmed death-1 pathway are in phase III trials across tumor types, including melanoma, lung cancer, and renal cell carcinoma. In keeping with their unique mechanism of action, these immune checkpoint inhibitors have shown both conventional and unconventional response patterns, including initial apparent tumor progression followed by regression, and adverse events (AEs) that are likely immune-related. Advanced practitioners (APs) treating patients receiving immuno-oncology agents are in a key position to educate patients about expectations with these therapies and to screen patients for AEs and initiate appropriate and timely interventions. This review summarizes current immune checkpoint inhibitor data and provides patient management strategies for APs to optimize patient outcomes with these novel therapies.

Immunotherapy and lung cancer: current developments and novel targeted therapies

Non-small-cell lung cancer (NSCLC) is a highly prevalent and aggressive disease. In the metastatic setting, major advances include the incorporation of immunotherapy and targeted therapies into the clinician's therapeutic armamentarium. Standard chemotherapeutic regimens have long been reported to interfere with the immune response to the tumor; conversely, antitumor immunity may add to the effects of those therapies. The aim of immunotherapy is to specifically enhance the immune response directed to the tumor. Recently, many trials addressed the role of such therapies for metastatic NSCLC treatment: ipilimumab, tremelimumab, nivolumab and lambrolizumab are immunotherapeutic agents of main interest in this field. In addition, anti-tumor vaccines, such as MAGE-A3, Tecetomide, TG4010, CIMAvax, ganglioside vaccines, tumor cell vaccines and dendritic cell vaccines, emerged as potent inducers of immune response against the tumor. The current work aims to address the most recent developments regarding these innovative immunotherapies and their implementation in the treatment of metastatic NSCLC.

Emerging antibody-based therapeutic strategies for bladder cancer: A systematic review

Bladder cancer is the most common malignancy of the urinary tract, presents the highest recurrence rate among solid tumors and is the second leading cause of death in genitourinary cancers. Despite recent advances in understanding of pathophysiology of the disease, the management of bladder cancer patients remains a clinically challenging problem. Particularly, bladder tumors invading the muscularis propria and disseminated disease are often not responsive to currently available therapeutic approaches, which include surgery and conventional chemotherapy. Antibody-based therapeutic strategies have become an established treatment option for over a decade in several types of cancer. However, bladder cancer has remained mostly an "orphan disease" regarding the introduction of these novel therapeutics, which has been translated in few improvements in patients overall survival. In order to shift this paradigm, several clinical studies involving antibody-based therapeutic strategies targeting the most prominent bladder cancer-related biomolecular pathways and immunological mediators are ongoing. This systematic review explores antibody-based therapeutics for bladder cancer undergoing clinical trial and discusses the future perspectives in this field, envisaging the development of more effective guided therapeutics.

Immune Effects of Chemotherapy, Radiation, and Targeted Therapy and Opportunities for Combination With Immunotherapy

There have been significant advances in cancer treatment over the past several years through the use of chemotherapy, radiation therapy, molecularly targeted therapy, and immunotherapy. Despite these advances, treatments such as monotherapy or monomodality have significant limitations. There is increasing interest in using these strategies in combination; however, it is not completely clear how best to incorporate molecularly targeted and immune-targeted therapies into combination regimens. This is particularly pertinent when considering combinations with immunotherapy, as other types of therapy may have significant impact on host immunity, the tumor microenvironment, or both. Thus, the influence of chemotherapy, radiation therapy, and molecularly targeted therapy on the host anti-tumor immune response and the host anti-host response (ie, autoimmune toxicity) must be taken into consideration when designing immunotherapy-based combination regimens. We present data related to many of these combination approaches in the context of investigations in patients with melanoma and discuss their potential relationship to management of patients with other tumor types. Importantly, we also highlight challenges of these approaches and emphasize the need for continued translational research.

IL-21: a pleiotropic cytokine with potential applications in oncology

Interleukin- (IL-) 21 is a pleiotropic cytokine that regulates the activity of both innate and specific immunity. Indeed, it costimulates T and natural killer (NK) cell proliferation and function and regulates B cell survival and differentiation and the function of dendritic cells. In addition, IL-21 exerts divergent effects on different lymphoid cell leukemia and lymphomas, as it may support cell proliferation or on the contrary induce growth arrest or apoptosis of the neoplastic lymphoid cells. Several preclinical studies showed that IL-21 has antitumor activity in different tumor models, through mechanism involving the activation of NK and T or B cell responses. Moreover, IL-21's antitumor activity can be potentiated by its combination with other immune-enhancing molecules, monoclonal antibodies recognizing tumor antigens, chemotherapy, or molecular targeted agents. Clinical phase I-II studies of IL-21 in cancer patients showed immune stimulatory properties, acceptable toxicity profile, and antitumor effects in a fraction of patients. In view of its tolerability, IL-21 is also suitable for combinational therapeutic regimens with other agents. This review will summarize the biological functions of IL-21, and address its role in lymphoid malignancies and preclinical and clinical studies of cancer immunotherapy.

Immunotherapy in lung cancer

Immunotherapy has emerged in recent years as a promising therapeutic approach in lung cancer. Two approaches are of particular interest: immune checkpoint inhibition, which aims to counteract the physiologic mechanisms of immune tolerance co-opted by some tumors, and vaccine therapy, which enables enhanced exposure to tumor antigen. Immune checkpoint therapies include the monoclonal antibody blockade of the cytotoxic T-lymphocyte antigen-4 (CTLA-4) with ipilimumab, as well as antibody blockade of the programmed cell death-1 (PD-1) receptor and the PD-1 ligand. These immune checkpoint therapies have been evaluated in both non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC) with early evidence of activity. Vaccines include antigen specific therapies which induce specific antitumor immunity against relevant tumor-associated antigens. In lung cancer, these include the melanoma-associated antigen-A3 (MAGE-A3), membrane-associated glycoprotein (MUC-1), and the epidermal growth factor receptor (EGFR). Whole tumor vaccines have also been evaluated in lung cancer and influence the patient's immune system to allow recognition of the tumor as foreign creating de novo immunity. This review summarizes the evidence to date for the efficacy and safety of immunotherapies in lung cancer.

The role of checkpoints in the treatment of GBM

Targeted immunotherapy is founded on the principle that augmentation of effector T cell activity in the tumor microenvironment can translate to tumor regression. Targeted checkpoint inhibitors in the form of agonist or antagonist monoclonal antibodies have come to the fore as a promising strategy to activate systemic immunity and enhance T cell activity by blocking negative signals, enhancing positive signals, or altering the cytokine milieu. This review will examine several immune checkpoints and checkpoint modulators that play a role in cancer pathogenesis, with an emphasis on malignant gliomas.

Tumor antigen-targeting monoclonal antibody-based immunotherapy: Orchestrating combined strategies for the development of long-term antitumor immunity

Tumor antigen (TA)-targeting monoclonal antibody (mAb)-based treatments are considered to be one of the most successful strategies in cancer therapy. Besides targeting TAs and inducing tumor cell death, such antibodies interact with immune cells through Fc-dependent mechanisms to induce adaptive memory immune responses. However, multiple inhibitory/immunosuppressive pathways can be induced by tumor cells to limit the establishment of an efficient antitumor response and consequently a sustained clinical response to TA-targeting mAbs. Here, we provide an overview on how TA-targeting mAbs in combination with conventional cancer therapies and/or inhibitors of key immunosuppressive pathways might represent promising approaches to achieve long-term tumor control.

Combining chemotherapy and checkpoint blockade in thoracic cancer: how to proceed?

SUMMARY 

Given the impressive efficacy of immune checkpoint blockade in thoracic malignancies, and the recently discovered immune-stimulating properties of many cytotoxic drugs, a logical next step would be to combine these treatments. However, the rational design of clinical trials investigating these combinations is hampered by a lack of knowledge regarding the overall immunogenic effects of the different chemotherapeutics. Here, we give an overview of the field with regard to checkpoint blockade and the immunological effects of cytotoxic chemotherapeutics, with particular focus on preclinical and clinical studies investigating the combination of these two treatment modalities. We discuss the hurdles that need to be overcome in order to optimally exploit chemotherapy and immune checkpoint blockade combinations in thoracic cancers.

Efficacy of chemotherapy in limited-disease small-cell lung cancer

SUMMARY Small-cell lung cancer (SCLC) accounts for approximately 13% of all lung cancers, and limited-disease SCLC is defined as a disease that can be encompassed within a tolerable radiation field. Concurrent chemoradiotherapy is considered to be the standard treatment for limited-disease SCLC. In both concurrent and consolidation chemoradiotherapies, the combination of etoposide and cisplatin is considered to be a standard chemotherapy regimen. To develop novel treatment for SCLC, several clinical trials of molecular-targeted therapy or immunotherapy have been reported. However, no molecular-targeted drug has shown clinical activity in limited-disease SCLC. In future studies, understanding the molecular profile of SCLC will be necessary for the development of molecular-targeted therapies for SCLC. This review provides an overview of chemotherapy regimens for limited-disease SCLC.