Phase III study of adjuvant vaccination with Bec2/bacille Calmette-Guerin in responding patients with limited-disease small-cell lung cancer (European Organisation for Research and Treatment of Cancer 08971-08971B; Silva Study)

Small cell lung cancer: will recent progress lead to improved outcomes?

Small cell lung cancer (SCLC) is an aggressive neuroendocrine malignancy with a unique natural history characterized by a short doubling time, high growth fraction, and early development of widespread metastases. Although a chemotherapy- and radiation-sensitive disease, SCLC typically recurs rapidly after primary treatment, with only 6% of patients surviving 5 years from diagnosis. This disease has been notable for the absence of major improvements in its treatment: Nearly four decades after the introduction of a platinum-etoposide doublet, therapeutic options have remained virtually unchanged, with correspondingly little improvement in survival rates. Here, we summarize specific barriers and challenges inherent to SCLC research and care that have limited progress in novel therapeutic development to date. We discuss recent progress in basic and translational research, especially in the development of mouse models, which will provide insights into the patterns of metastasis and resistance in SCLC. Opportunities in clinical research aimed at exploiting SCLC biology are reviewed, with an emphasis on ongoing trials. SCLC has been described as a recalcitrant cancer, for which there is an urgent need for accelerated progress. The NCI convened a panel of laboratory and clinical investigators interested in SCLC with a goal of defining consensus recommendations to accelerate progress in the treatment of SCLC, which we summarize here.

Small cell lung cancer (SCLC): no treatment advances in recent years

Small cell lung cancer (SCLC) is an aggressive malignancy with a distinct natural history and dismal prognosis. Given its predisposition for early dissemination, patients are commonly diagnosed with metastatic disease and chemotherapy is regarded as the cornerstone of approved treatment strategies. However, over the last 30 years there has been a distinct paucity of significant breakthroughs in SCLC therapy. Thus, SCLC is characterized as a recalcitrant neoplasm with limited therapeutic options. By employing well-established research approaches, proven to be efficacious in non-small cell lung cancer (NSCLC), a growing amount of data has shed light on the molecular biology of SCLC and enhanced our knowledge of the "drivers" of tumor cell survival and proliferation. New therapeutic targets have emerged, but no significant improvement in patients' survival has been demonstrated thus far. In a sense, the more we know, the more we fail. Nowadays this is starting to change and methodical research efforts are underway. It is anticipated that the next decade will see a revolution in the treatment of SCLC patients with the application of effective precision medicine and immunotherapy strategies.

Cancer stem cells in small cell lung cancer

Small cell lung cancer (SCLC) is one of the most aggressive lung tumors, with poor survival rates. Although patients may initially respond to treatment, this is followed by rapid development of drug resistance and disease progression. SCLC patients often present with metastasis at time of diagnosis, ruling out surgery as a treatment option. Currently, treatment options for this disease remain limited and platinum-based chemotherapy is the treatment of choice. A better understanding of the biology of SCLC could allow us to identify new therapeutic targets. Cancer stem cell (CSC) theory is currently crucial in cancer research and could provide a viable explanation for the heterogeneity, drug resistance, recurrence and metastasis of several types of tumors. Some characteristics of SCLC, such as aggressiveness, suggest that this kind of tumor could be enriched in CSCs, and drug resistance in SCLC could be attributable to the existence of a CSC subpopulation in SCLC. Herein we summarize current understanding of CSC in SCLC, including the evidence for CSC markers and signaling pathways involved in stemness. We also discuss potential ongoing strategies and areas of active research in SCLC, such as immunotherapy, that focus on inhibition of signaling pathways and targeting molecules driving stemness. Understanding of signaling pathways and the discovery of new therapeutic markers specific to CSCs will lead to new advances in therapy and improvements in prognosis of SCLC patients. Therefore, evaluation of these CSC-specific molecules and pathways may become a routine part of SCLC diagnosis and therapy.

Cancer stem cells and immunoresistance: clinical implications and solutions

Tumor cells can be contained, but not eliminated, by traditional cancer therapies. A cell minor subpopulation is able to evade attack from therapies and may have cancer stem cell (CSC) characteristics, including self-renewal, multiple differentiation and tumor initiation (tumor initiating cells, or TICs). Thus, CSCs/TICs, aided by the microenvironment, produce more differentiated, metastatic cancer cells which the immune system detects and interacts with. There are three phases to this process: elimination, equilibrium and escape. In the elimination phase the immune system recognizes and destroys most of the tumor cells. Then the latency phase begins, consisting of equilibrium between immunological elimination and tumor cell growth. Finally, a minor attack-resistant subpopulation escapes and forms a clinically detectable tumor mass. Herein we review current knowledge of immunological characterization of CSCs/TICs. Due to the correlation between CTCs/TICs and drug resistance and metastasis, we also comment on the crucial role of key molecules involved in controlling CSCs/TICs properties; such molecules are essential to detect and destroy CSCs/TICs. Monoclonal antibodies, antibody constructs and vaccines have been designed to act against CSCs/TICs, with demonstrated efficacy in human cancer xenografts and some antitumor activity in human clinical studies. Therefore, therapeutic strategies that selectively target CSCs/TICs warrant further investigation. Better understanding of the interaction between CSCs and tumor immunology may help to identify strategies to eradicate the minor subpopulation that escapes conventional therapy attack, thus providing a solution to the problem of drug resistance and metastasis.

Personalized Therapy of Small Cell Lung Cancer

Small cell lung cancer (SCLC) is an aggressive, poorly differentiated neuroendocrine carcinoma with distinct clinical, pathological and molecular characteristics. Despite robust responses to initial chemotherapy and radiation, the prognosis of patients with SCLC remains poor with an overall 5-year survival rate of less than 10 %. Despite the fact that numerous molecularly targeted approaches have thus far failed to demonstrate clinical utility in SCLC, further advances will rely on better definition of the biological pathways that drive survival, proliferation and metastasis. Recent next-generation, molecular profiling studies have identified many new therapeutic targets in SCLC, as well as extreme genomic instability which explains the high degree of resistance. A wide variety of anti-angiogenic agents, growth factor inhibitors, pro-apoptotic agents, and epigenetic modulators have been evaluated in SCLC and many studies of these strategies are on-going. Perhaps the most promising approaches involve agents targeting cancer stem cell pathways and immunomodulatory drugs that interfere with the PD1 and CTLA-4 pathways. SCLC offers many barriers to the development of successful therapy, including limited tumor samples, inadequate preclinical models, high mutational burden, and aggressive tumor growth which impairs functional status and hampers enrollment on clinical trials.

Immune Therapy

Lung cancer has long been considered an unsuitable target for immunotherapy due to its proposed immunoresistant properties. However, recent evidence has shown that anti-tumor immune responses can occur in lung cancer patients, paving the way for lung cancer as a novel target for immunotherapy. In order to take full advantage of the potential of immunotherapy, research is focusing on the presence and function of various immunological cell types in the tumor microenvironment. Immune cells which facilitate or inhibit antitumor responses have been identified and their prognostic value in lung cancer has been established. Knowledge regarding these pro- and anti-tumor immune cells and their mechanisms of action has facilitated the identification of numerous potential immunotherapeutic strategies and opportunities for intervention. A plethora of immunotherapeutic approaches is currently being developed and studied in lung cancer patients and phase 3 clinical trials are ongoing. Many different immunotherapies have shown promising clinical effects in patients with limited and advanced stage lung cancer, however, future years will have to tell whether immunotherapy will earn its place in the standard treatment of lung cancer.

Clinical trials exploring the benefit of immunotherapy and radiation in cancer treatment: A review of the past and a look into the future

Cancer immunotherapy is rapidly redefining the standard of cancer care. The role of radiation therapy in eliciting antitumoral immune response is also being actively investigated in combination with various immunotherapeutic agents to exploit potential synergy between the 2 modalities. In this review, we summarize the rationale and results of past and ongoing clinical trials that combined the use of radiation therapy and immunogenic agents such as vaccines, cytokines, immune checkpoint inhibitors, costimulatory agonists, and myeloid activators.

Novel therapies in small cell lung cancer

Small cell lung cancer (SCLC) is an aggressive neuroendocrine tumor of the lung with a tendency to metastasize widely early in the course of the disease. The VA staging system classifies the disease into limited stage (LS) which is confined to one hemithorax and can be included into one radiation field or extensive stage (ES) which extends beyond one hemithorax. Current standard of care is concurrent chemoradiation for LS disease and chemotherapy alone for ES disease. Only a quarter of patients with LS disease will be cured with current standard treatments and majority of the patients ultimately succumb to their disease. A very complex genetic landscape of SCLC accounts for its resistance to conventional therapy and a high recurrence rate, however, at the same time this complexity can form the basis for effective targeted therapy for the disease. In recent years, several different therapeutic strategies and targeted agents have been under investigation for their potential role in SCLC. Several of them including EGFR TKIs, BCR-ABL TKIs, mTOR inhibitors, and VEGF inhibitors have been unsuccessful in showing a survival advantage in this disease. Several others including DNA repair inhibitors, cellular developmental pathway inhibitors, antibody drug conjugates (ADCs), as well as immune therapy with vaccines, immunomodulators, and immune checkpoint inhibitors are being tested. So far, none of these agents are approved for use in SCLC and the majority are in phase I/II clinical trials, with immune checkpoint inhibitors being the most promising therapeutic strategy. In this article, we will discuss these novel therapeutic agents and currently available data in SCLC.

Lung cancer: Biology and treatment options

Lung cancer remains the leading cause of cancer mortality in men and women in the U.S. and worldwide. About 90% of lung cancer cases are caused by smoking and the use of tobacco products. However, other factors such as radon gas, asbestos, air pollution exposures, and chronic infections can contribute to lung carcinogenesis. In addition, multiple inherited and acquired mechanisms of susceptibility to lung cancer have been proposed. Lung cancer is divided into two broad histologic classes, which grow and spread differently: small-cell lung carcinomas (SCLCs) and non-small cell lung carcinomas (NSCLCs). Treatment options for lung cancer include surgery, radiation therapy, chemotherapy, and targeted therapy. Therapeutic-modalities recommendations depend on several factors, including the type and stage of cancer. Despite the improvements in diagnosis and therapy made during the past 25 years, the prognosis for patients with lung cancer is still unsatisfactory. The responses to current standard therapies are poor except for the most localized cancers. However, a better understanding of the biology pertinent to these challenging malignancies, might lead to the development of more efficacious and perhaps more specific drugs. The purpose of this review is to summarize the recent developments in lung cancer biology and its therapeutic strategies, and discuss the latest treatment advances including therapies currently under clinical investigation.

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.

Prognostic value of pretreatment serum lactate dehydrogenase level in patients with solid tumors: a systematic review and meta-analysis

Although most studies have reported that high serum lactate dehydrogenase (LDH) levels are associated with poor prognosis in several malignancies, the consistency and magnitude of the impact of LDH are unclear. We conducted the first comprehensive meta-analysis of the prognostic relevance of LDH in solid tumors. Overall survival (OS) was the primary outcome; progression-free survival (PFS) and disease-free survival (DFS) were secondary outcomes. We identified a total of 68 eligible studies that included 31,857 patients. High LDH was associated with a HR for OS of 1.48 (95% CI = 1.43 to 1.53; P < 0.00001; I² = 93%), an effect observed in all disease subgroups, sites, stages and cutoff of LDH. HRs for PFS and DFS were 1.70 (95% CI = 1.44 to 2.01; P < 0.00001; I² = 13%) and 1.86(95% CI = 1.15 to 3.01; P = 0.01; I² = 88%), respectively. Analysis of LDH as a continuous variable showed poorer OS with increasing LDH (HR 2.11; 95% CI = 1.35 to 3.28). Sensitivity analyses showed there was no association between LDH cutoff and reported HR for OS. High LDH is associated with an adverse prognosis in many solid tumors and its additional prognostic and predictive value for clinical decision-making warrants further investigation.

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.

Immunotherapy prospects in the treatment of lung cancer and mesothelioma

A very recent finding is the role of immune activation in cancer. The assumption that stimulating the patient's immune system to attack tumors is a valuable treatment option in malignant diseases has gained more acceptance. However the high immunosuppressive effects caused by the tumor limits this beneficial effect. There is a delicate balance between immunoactivation and immunosuppression in a patient. Especially in non small cell lung cancer (NSCLC), the role of immunosuppressive cells hampering immune activation is high. But also in small cell lung cancer (SCLC) and mesothelioma immunosuppressive activity is high. This is suggested to be related to the type of tumor, advanced stage of the disease, and the tumor load. In this review, we provide an overview of the progress and challenges in the immunotherapeutic approaches in lung cancer. We conclude with the concept that immunotherapy in thoracic malignancies must be tailored made to the balance of the immune system.

Targeted therapies for small cell lung cancer: Where do we stand?

Small cell lung cancer (SCLC) accounts for 15% of lung cancer cases and is associated with a dismal prognosis. Standard therapeutic regimens have been improved over the past decades, but without a major impact on patient survival. The development of targeted therapies based on a better understanding of the molecular basis of the disease is urgently needed. At the genetic level, SCLC appears very heterogenous, although somatic mutations targeting classical oncogenes and tumor suppressors have been reported. SCLC also possesses somatic mutations in many other cancer genes, including transcription factors, enzymes involved in chromatin modification, receptor tyrosine kinases and their downstream signaling components. Several avenues have been explored to develop targeted therapies for SCLC. So far, however, there has been limited success with these targeted approaches in clinical trials. Further progress in the optimization of targeted therapies for SCLC will require the development of more personalized approaches for the patients.

Approaches to improve development methods for therapeutic cancer vaccines

Therapeutic cancer vaccines are an immunotherapy that amplify or induce an active immune response against tumors. Notably, limitations in the methodology for existing anti-cancer drugs may subsist while applying them to cancer vaccine therapy. A retrospective analysis was performed using information obtained from ClinicalTrials.gov, PubMed, and published articles. Our research evaluated the optimal methodologies for therapeutic cancer vaccines based on (1) patient populations, (2) immune monitoring, (3) tumor response evaluation, and (4) supplementary therapies. Failure to optimize these methodologies at an early phase may impact development at later stages; thus, we have proposed some points to be considered during the early phase. Moreover, we compared our proposal with the guidance for industry issued by the US Food and Drug Administration in October 2011 entitled "Clinical Considerations for Therapeutic Cancer Vaccines". Consequently, while our research was aligned with the guidance, we hope it provides further insights in order to predict the risks and benefits and facilitate decisions for a new technology. We identified the following points for consideration: (1) include in the selection criteria the immunological stage with a prognostic value, which is as important as the tumor stage; (2) select immunological assays such as phenotype analysis of lymphocytes, based on their features and standardize assay methods; (3) utilize optimal response criteria for immunotherapy in therapeutic cancer vaccine trials; and (4) consider supplementary therapies, including immune checkpoint inhibitors, for future therapeutic cancer vaccines.

New concepts of biomarkers and clinical outcomes for therapeutic cancer vaccines in clinical trials

Aim: This study aimed to derive meaningful parameters for immune monitoring during cancer vaccine development by analysis of the literature. Methods: This retrospective study was based on analysis of clinical trials registered at ClinicalTrials.gov and published data available on PubMed. Results: The most common sample evaluated in immune monitoring was peripheral blood. All trials employed ELISA for detecting a humoral immune response; however, cellular immune assays were not used across trials. Most cellular immune assays failed to correlate with clinical outcome, although results of other methods did. Conclusion: Standardization of the cellular immune assays across trials is important for predicting the effects of therapeutic cancer vaccines when considering the reliability and characteristics of the methods. Currently, assays mostly target detection of T-cell function, such as proliferation and cytokine release; however, T-cell phenotype analysis in peripheral blood and/or tumor sites may also be considered in the future.

Advances in pharmacotherapy of small cell lung cancer

INTRODUCTION

Small cell lung cancer (SCLC) is an aggressive malignancy characterized by early metastatic dissemination and responsiveness to initial therapy. The incidence of SCLC has been declining over the past two decades. Limited-stage SCLC is a potentially curable disease with long-term survival of ∼ 20% when treated with platinum-based chemotherapy plus concurrent thoracic radiation and prophylactic cranial irradiation. For patients with extensive-stage SCLC, survival can be increased with combination platinum-based chemotherapy, but the disease remains incurable.

AREAS COVERED

This review looks at the current advances in pharmacotherapy for SCLC.

EXPERT OPINION

Many chemotherapeutic strategies and newer cytotoxic agents have been evaluated in SCLC, and some had promising activity in early clinical trials. However, none have demonstrated consistent improvements in outcome over standard platinum-based treatment. Similarly, although many potential molecular targets have been identified in preclinical studies of SCLC, molecularly targeted therapy has yet to demonstrate any substantial activity in clinical trials. Nonetheless, future advances in this disease will undoubtedly depend on improvements in our understanding of the molecular mechanisms that drive the proliferation and survival of SCLC cells.

Pilot study of a novel combination of two therapeutic vaccines in advanced non-small-cell lung cancer patients

Cancer vaccines contain tumor antigens in a pro-inflammatory context with the purpose to generate potent antitumor immune responses. However, tumor cells develop different immunosuppressive mechanisms that limit the effectiveness of an anticancer immune response. Therefore, therapeutic vaccine treatment alone is usually not sufficient to generate tumor regression or survival improvement, especially in the advanced disease scenario in which most clinical studies have been conducted. Combining cancer vaccines with different anticancer therapies such as chemotherapy, radiotherapy and other immunotherapeutic agents has had different levels of success. However, the combination of cancer vaccines with different mechanisms of action has not been explored in clinical trials. To address this issue, the current review summarizes the main clinical and immunological results obtained with two different therapeutic vaccines used in advanced non-small-cell lung cancer patients, inducing an immune response against epidermal growth factor (CIMAvax-EGF) and NGcGM3 ganglioside (racotumomab). We also discuss preliminary findings obtained in a trial of combination of these two vaccines and future challenges with these therapies.

[Advances of immunotherapy in small cell lung cancer]

小细胞肺癌（small cell lung cancer, SCLC）具有复杂的异质性，由于细胞起源、发病机制和驱动基因尚不明确，SCLC的诊治进展缓慢，鲜有突破，迫切需要新的治疗策略提高SCLC疗效。肿瘤免疫治疗可提高免疫系统识别和排除肿瘤细胞的能力，且对正常组织影响轻微。目前已经开展了肿瘤疫苗、过继细胞免疫治疗、细胞因子、checkpoint抑制剂等治疗SCLC的临床研究，ipilimumab是最有前景的药物。免疫治疗有望为SCLC治疗带来新的希望，未来还需要对SCLC的异质性、免疫治疗靶点不明确、免疫治疗耐受等影响免疫治疗疗效的问题开展进一步研究。

Health-related quality of life in small-cell lung cancer: a systematic review on reporting of methods and clinical issues in randomised controlled trials

Small-cell lung cancer represents about 15% of all lung cancers; increasingly, randomised controlled trials of this disease measure the health-related quality of life of patients. In this Systematic Review we assess the adequacy of reporting of health-related quality-of-life methods in randomised controlled trials of small-cell lung cancer, and the potential effect of this reporting on clinical decision making. Although overall reporting of health-related quality of life was acceptable, improvements are needed to optimise the use of health-related quality of life in randomised controlled trials.

Immunotherapy in lung cancer

Survival rates for metastatic lung cancer including non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC) are poor with 5-year survival of less than 5%. The use of molecular targeted therapies has improved median overall survival (OS) in a limited group of NSCLC patients whose tumors harbor specific genetic alterations. However for a large group of NSCLC and SCLC molecular alterations are not available to lead to direct targeted therapies. Recent favorable results of newer trials of therapeutic vaccines and checkpoint inhibitors have proven against the common belief that lung cancer is nonimmunogenic. In particular, the checkpoint inhibitors targeting cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) and the programmed death-1 (PD-1) pathway have shown durable clinical responses with manageable toxicity. Several phase II and III clinical trials testing the association of different schedule of chemotherapy and immunotherapy or immunotherapy alone are ongoing in lung cancer and important results are expected in the near future. However, more studies are needed to understand the optimal combination of immunotherapeutic agents with chemotherapy and radiation therapy for the treatment of NSCLC and SCLC.

Immunotherapy for lung cancer: ongoing clinical trials

ABSTRACT: Modulation of a patient’s immune system so that it acts against lung cancer cells has not been successful in the past decades. Advances in our understanding of the immune response to tumors resulted in the development of different kinds of novel immunotherapeutic agents. This has resulted in the development of two major approaches. First, antigen-specific immunotherapy or cancer vaccination, with the MAGE-A3 vaccine in resected early-stage non-small-cell lung cancer (NSCLC), the L-BLP25 vaccine in locally advanced NSCLC after chemoradiotherapy and belagenpumatucel-L and the TG4010 vaccine in advanced-stage NSCLC. Second, non-antigen-specific immunotherapy or cancer immunomodulation is reviewed, including how monoclonal antibodies modulate the interaction between antigen-presenting cells, T-lymphocytes and tumor cells (e.g., antibodies against CTLA-4, or against PD-1 receptor or its ligands). Recent Phase II trials with these treatments have shown promising results of efficacy and tolerability, which has led to testing in several large Phase III trials. Some of these are fully recruited, while others are still ongoing, and important results are be expected in the near future.

Glycosylation of glycolipids in cancer: basis for development of novel therapeutic approaches

Altered networks of gene regulation underlie many pathologies, including cancer. There are several proteins in cancer cells that are turned either on or off, which dramatically alters the metabolism and the overall activity of the cell, with the complex machinery of enzymes involved in the metabolism of glycolipids not being an exception. The aberrant glycosylation of glycolipids on the surface of the majority of cancer cells, associated with increasing evidence about the functional role of these molecules in a number of cellular physiological pathways, has received considerable attention as a convenient immunotherapeutic target for cancer treatment. This has resulted in the development of a substantial number of passive and active immunotherapies, which have shown promising results in clinical trials. More recently, antibodies to glycolipids have also emerged as an attractive tool for the targeted delivery of cytotoxic agents, thereby providing a rationale for future therapeutic interventions in cancer. This review first summarizes the cellular and molecular bases involved in the metabolic pathway and expression of glycolipids, both in normal and tumor cells, paying particular attention to sialosylated glycolipids (gangliosides). The current strategies in the battle against cancer in which glycolipids are key players are then described.

Immunotherapy treatments for small-cell lung cancer: past, present and future

Small-cell lung cancer remains a considerable cause of morbidity and mortality. To this day, first-line therapy continues to be a platinum agent with etoposide, combined with radiation therapy in cases of limited stage disease. Numerous, largely unsuccessful, attempts at controlling the disease have included different chemotherapy strategies, the utilization of antiangiogenic agents, tyrosine kinase inhibitors, mammalian target of rapamycin inhibitors and other treatment modalities. Immunotherapy, including vaccines, immune response modifiers, inhibitors of check point blockades and immunologic-targeted toxins may well be the future of treatment, not only to enhance the proven chemotherapy effects, but to improve the control of minimal residual disease and the response with salvage chemotherapy. This article reviews the current advances in immunotherapeutic strategies against small-cell lung cancer.

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.

Therapeutic vaccines in non-small cell lung cancer

Non-small cell lung cancer (NSCLC) unfortunately carries a very poor prognosis. Patients usually do not become symptomatic, and therefore do not seek treatment, until the cancer is advanced and it is too late to employ curative treatment options. New therapeutic options are urgently needed for NSCLC, because even current targeted therapies cure very few patients. Active immunotherapy is an option that is gaining more attention. A delicate and complex interplay exists between the tumor and the immune system. Solid tumors utilize a variety of mechanisms to evade immune detection. However, if the immune system can be stimulated to recognize the tumor as foreign, tumor cells can be specifically eliminated with little systemic toxicity. A number of vaccines designed to boost immunity against NSCLC are currently undergoing investigation in phase III clinical trials. Belagenpumatucel-L, an allogeneic cell vaccine that decreases transforming growth factor (TGF-β) in the tumor microenvironment, releases the immune suppression caused by the tumor and it has shown efficacy in a wide array of patients with advanced NSCLC. Melanoma-associated antigen A3 (MAGE-A3), an antigen-based vaccine, has shown promising results in MAGE-A3⁺ NSCLC patients who have undergone complete surgical resection. L-BLP25 and TG4010 are both antigenic vaccines that target the Mucin-1 protein (MUC-1), a proto-oncogene that is commonly mutated in solid tumors. CIMAVax is a recombinant human epidermal growth factor (EGF) vaccine that induces anti-EGF antibody production and prevents EGF from binding to its receptor. These vaccines may significantly improve survival and quality of life for patients with an otherwise dismal NSCLC prognosis. This review is intended to give an overview of the current data and the most promising studies of active immunotherapy for NSCLC.

The development of targeted therapy in small cell lung cancer

Small cell lung cancer (SCLC) is a highly aggressive cancer usually with distal metastasis and very poor prognosis. Chemotherapy is the treatment of choice for SCLC in all stages and an initial good response, but there is a high chance of disease relapse with an overall poor median survival for both stages. With increasing translational research and a better understanding of the molecular basis of cancer, a number of molecular targets have been identified in various preclinical studies. Targeted drugs have less toxicity than chemotherapy drugs, but no targeted agents have been approved for use in the treatment of SCLC patients to date. This review focuses on targeted therapies in SCLC.

Perspectives on immunotherapy in prostate cancer and solid tumors: where is the future?

The goals of any cancer therapy are to improve disease control, palliate pain and improve overall survival. We are fortunate to have in our cancer armamentarium two new immune-directed therapies which not only impact on disease control but also on overall survival. The first, sipuleucel-T, a cellular-based vaccine, was approved for prostate cancer and was shown to be safe with minimal toxicity. The second, ipilimumab, a monoclonal antibody directed to an immunologic checkpoint molecule, showed a survival benefit in patients with advanced melanoma. Benefit appeared to correlate in some cases with the development of autoimmune events, signaling that the immune system is in overdrive against the cancer. Where we are and where we will likely go are the topics to be discussed in this review.

Immunological monitoring of anticancer vaccines in clinical trials

Therapeutic anticancer vaccines operate by eliciting or enhancing an immune response that specifically targets tumor-associated antigens. Although intense efforts have been made for developing clinically useful anticancer vaccines, only a few Phase III clinical trials testing this immunotherapeutic strategy have achieved their primary endpoint. Here, we report the results of a retrospective research aimed at clarifying the design of previously completed Phase II/III clinical trials testing therapeutic anticancer vaccines and at assessing the value of immunological monitoring in this setting. We identified 17 anticancer vaccines that have been investigated in the context of a completed Phase II/III clinical trial. The immune response of patients receiving anticancer vaccination was assessed for only 8 of these products (in 15 distinct studies) in the attempt to identify a correlation with clinical outcome. Of these studies, 13 were supported by a statistical correlation study (Log-rank test), and no less than 12 identified a positive correlation between vaccine-elicited immune responses and disease outcome. Six trials also performed a Cox proportional hazards analysis, invariably demonstrating that vaccine-elicited immune responses have a positive prognostic value. However, despite these positive results in the course of early clinical development, most therapeutic vaccines tested so far failed to provide any clinical benefit to cancer patients in Phase II/III studies. Our research indicates that evaluating the immunological profile of patients at enrollment might constitute a key approach often neglected in these studies. Such an immunological monitoring should be based not only on peripheral blood samples but also on bioptic specimens, whenever possible. The evaluation of the immunological profile of cancer patients enrolled in early clinical trials will allow for the identification of individuals who have the highest chances to benefit from anticancer vaccination, thus favoring the rational design of Phase II and Phase III studies. This approach will undoubtedly accelerate the clinical development of therapeutic anticancer vaccines.

Colorectal cancer defeating? Challenge accepted!

Colorectal tumours are actually considered as aberrant organs, within it is possible to notice a different stage of cell growth and differentiation. Their origin is reported to arise from a subpopulation of tumour cells endowed with, just like the healthy stem cells, self-renewal and aberrant multi-lineage differentiation capacity likely to be called colorectal cancer stem cells (CCSCs). Cancer stem cells (CSCs) fate, since their origin, reflects the influences from their microenvironment (or niche) both in the maintenance of stemness, in promoting their differentiation, and in inducing epithelial-mesenchymal transition, responsible of CSCs dissemination and subsequent formation of metastatic lesions. The tumour cells heterogeneity and their immuno-response resistance nowadays probably responsible of the failure of the conventional therapies, make this research field an open issue. Even more importantly, our increasing understanding of the cellular and molecular mechanisms that regulate CSC quiescence and cell cycle regulation, self-renewal, chemotaxis and resistance to cytotoxic agents, is expected to eventually result in tailor-made therapies with a significant impact on the morbidity and overall survival of colorectal cancer patients.

Beyond the standard of care: a review of novel immunotherapy trials for the treatment of lung cancer

BACKGROUND

Lung cancer is the most common cause of cancer-related death in the United States, yet traditional chemotherapy fails to provide long-term benefit for many patients. New approaches are needed to improve overall survival beyond the current standard of care.

METHODS

This review discusses recent clinical trials using immunotherapy techniques to treat both non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC) and highlights ongoing immunotherapy research efforts at our center.

RESULTS

For NSCLC, phase II clinical trials have examined allogeneic vaccines that target either mucin 1 (MUC1), epidermal growth factor or melanoma-associated antigen 3. These vaccines are now undergoing larger phase III trials. An autologous cellular therapy directed against transforming growth factor beta-2 and a recombinant protein with antitumor properties have also shown promise in prolonging survival in NSCLC in phase II trials. The monoclonal antibodies ipilimumab, BMS-936558 (anti-PD-1), and BMS936559 (anti-PD-L1) lead to enhanced T-cell-mediated antitumor effects and have produced objective responses in early-phase clinical trials. Studies for SCLC also exist, such as a novel vaccine therapy targeting p53.

CONCLUSIONS

Recent clinical trials in lung cancer demonstrate the potential of immunotherapeutics to increase overall survival in patients with lung cancer compared with the current standard of care.

Positioning ganglioside D3 as an immunotherapeutic target in lymphangioleiomyomatosis

Tumors that develop in lymphangioleiomyomatosis (LAM) as a consequence of biallelic loss of TSC1 or TSC2 gene function express melanoma differentiation antigens. However, the percentage of LAM cells expressing these melanosomal antigens is limited. Here, we report the overexpression of ganglioside D3 (GD3) in LAM. GD3 is a tumor-associated antigen otherwise found in melanoma and neuroendocrine tumors; normal expression is largely restricted to neuronal cells in the brain. We also observed markedly reduced serum antibody titers to GD3, which may allow for a population of GD3-expressing LAM cells to expand within patients. This is supported by the demonstrated sensitivity of cultured LAM cells to complement mediated cytotoxicity via GD3 antibodies. GD3 can serve as a natural killer T (NKT) cell antigen when presented on CD1d molecules expressed on professional antigen-presenting cells. Although CD1d-expressing monocyte derivatives were present in situ, enhanced NKT-cell recruitment to LAM lung was not observed. Cultured LAM cells retained surface expression of GD3 over several passages and also expressed CD1d, implying that infiltrating NKT cells can be directly cytotoxic toward LAM lung lesions. Immunization with antibodies to GD3 may thus be therapeutic in LAM, and enhancement of existing NKT-cell infiltration may be effective to further improve antitumor responses. Overall, we hereby establish GD3 as a suitable target for immunotherapy of LAM.

[Immunotherapy for non-small cell lung cancer--novel approaches to improve patient outcome]

简介

通常，非小细胞肺癌（non-small cell lung cancer, NSCLC）诊断已为晚期，且预后较差。目前的NSCLC标准治疗总体治愈率低，有必要开发新的治疗方法。我们在本综述中提供了最新的免疫治疗干预临床数据，该手段可能能够提高免疫系统对细胞的应答。

方法

我们针对临床应用免疫疗法治疗NSCLC，检索了PubMed上的文章以及最近肿瘤学术会议上的摘要。

结果

Ⅱ期临床研究结果表明，靶向肿瘤细胞本身或其异常表达的肿瘤标志物的疫苗治疗（mucin1，黑色素瘤相关抗原3，或表皮生长因子），有望作为NSCLC免疫疗法。非抗原免疫治疗，如抗细胞毒T淋巴细胞抗原4单克隆抗体、talactoferrin alfa和toll-样受体9拮抗剂，作用于激活的免疫系统，与肿瘤抗原无关，可用于晚期NSCLC的治疗。目前一些免疫治疗正在进行Ⅲ期研究，以确定最佳治疗方案，并与NSCLC标准治疗对照，确定其临床疗效。

结论

越来越多的证据表明肺部肿瘤存在免疫应答。免疫治疗，包括疫苗治疗和非抗原免疫调节方法，可改善NSCLC的预后。而且，提高抗肿瘤免疫应答的治疗，与化疗有协同作用。生物标志物的明确以及免疫治疗作用机制的进一步阐明对于确定哪些患者更可能从免疫治疗中获益至关重要。

Clinical evaluation of therapeutic cancer vaccines

Therapeutic cancer vaccines are an immunotherapy that targets tumor antigens to induce an active immune response. To date, Provenge® is the only therapeutic cancer vaccine approved by the United States Food and Drug Administration. Although therapeutic cancer vaccines have not been approved by the European Medicines Agency (EMA), they have been approved in several countries other than the United States (US) and the European Union (EU). Provenge® is the only approved cancer vaccine that showed significant primary endpoint efficacy in a phase III study at the time of approval. Retrospective analysis of 23 completed or terminated phase III studies showed that 74% (17/23) failed to demonstrate significant efficacy in the primary endpoint. The reasons for failure were surveyed in 13 of the 17 studies. Despite efforts to minimize tumor burden, including surgery and induction chemotherapy before therapeutic cancer vaccine therapy, 69% (9/13) of the phase III studies failed. These findings indicate that tumor burden may not be the only prognostic factor. Immunological response has often been used as a predictive factor, and a small number of sub-group analyses have succeeded in showing that immunological response is associated with the efficacy of therapeutic cancer vaccines. Being a prognostic factor, inclusion of immunological response in addition to tumor stage in the eligibility criteria or sub-group analysis may minimize study population heterogeneity, a key factor in the success of phase III studies.

The role of the immune response in merkel cell carcinoma

Merkel cell carcinoma (MCC) is an aggressive neuroendocrine skin cancer. The Merkel cell polyomavirus (MCPyV) is implicated in its pathogenesis. Immune mechanisms are also implicated. Patients who are immunosuppressed have an increased risk. There is evidence that high intratumoral T-cell counts and immune transcripts are associated with favorable survival. Spontaneous regressions implicate immune effector mechanisms. Immunogenicity is also supported by observation of autoimmune paraneoplastic syndromes. Case reports suggest that immune modulation, including reduction of immune suppression, can result in tumor regression. The relationships between MCPyV infection, the immune response, and clinical outcome, however, remain poorly understood. Circulating antibodies against MCPyV antigens are present in most individuals. MCPyV-reactive T cells have been detected in both MCC patients and control subjects. High intratumoral T-cell counts are also associated with favorable survival in MCPyV-negative MCC. That the immune system plays a central role in preventing and controlling MCC is supported by several observations. MCCs often develop, however, despite the presence of humoral and cellular immune responses. A better understanding on how MCPyV and MCC evade the immune response will be necessary to develop effective immunotherapies.

Targeted therapies in small cell lung cancer

Lung cancer is the leading cause of cancer-related mortality. Small cell lung cancer (SCLC) accounted for 12.95% of all lung cancer histological types in 2002. Despite trends toward modest improvement in survival, the outcome remains extremely poor. Chemotherapy is the cornerstone of treatment in SCLC. More than two-thirds of patients who succumb to lung cancer in the United States are over 65 years old. Elderly patients tolerate chemotherapy poorly and need novel therapeutic agents. Targeted drugs have less toxicity than chemotherapy drugs, but no targeted agents have been approved for use in the treatment of SCLC patients to date. Certain new targeted agents, including gefitinib, bevacizumab and Bcl-2 inhibitors, offer a promise of improved outcomes, however negative results are more commonly reported than positive. This review focuses on targeted therapies in SCLC.

Glycans as targets for therapeutic antitumor antibodies

Glycans represent a vast class of molecules that modify either proteins or lipids. They exert and regulate important and complex functions in both normal and cancer cell metabolism. As such, the most immunogenic glycans have been targeted in passive and active immunotherapy in human cancer for the past 25 years but it is only recently that techniques have become available to uncover novel glycan targets. The main focus of this review article is to highlight why and how monoclonal antibodies (mAbs) recognizing glycans, and in particular the glycans expressed on glycolipids, are being used in various strategies to target and kill cancer cells. The article reports on the historical use of mAbs and on very recent progress made in antitumor therapy using the anti-GD2 mAb and the antiganglioside mAbs, anti-N-glycolylneuraminic acid mAb and anti-Lewis mAb. Anti-GD2 is showing great promise in Phase III clinical trials in adjuvant treatment of neuroblastoma. Racotumomab, an anti-idiotypic mAb mimicking N-glycolylneuraminic acid-containing gangliosides, is currently being tested in a randomized, controlled Phase II/III clinical trial. This article also presents various strategies used by different groups to develop mAbs against these naturally poorly immunogenic glycans.

Development of antibody therapeutics for small cell lung cancer

INTRODUCTION

Small cell lung cancer (SCLC) is one of most aggressive cancers and only modest improvements have been achieved in overall survival over last 30 years. In recent years, antibody therapeutics has been actively studied and shown promise in treatment of SCLC.

AREAS COVERED

A comprehensive literature search through Medline and the registry database of clinical trials (ClinicalTrials.gov) was performed to collect all relevant preclinical and clinical data. The diverse antibody therapeutics which target against different antigens including VEGE-A, CEA, IGF-1R, CD56, EpCAM, CTLA-4, gangliosides GD2 and GD3, Lewis Y and tenascin-C are now under clinical investigation for therapeutic effects in SCLC.

EXPERT OPINION

During the last few decades, progresses have been made in antibody therapy for SCLC, however great challenges still remain. The major reasons are the complexity of SCLC and a lack of understanding of cancer immunology. The profound studies of signaling pathways involved in carcinogenesis, proliferation, metastasis and apoptosis in SCLC are crucial for the identification of new therapeutic targets and biomarkers. Moreover, a better understanding of the interplay between cancer and the immune system is a new direction for the design of more effective antibody therapeutics.

Anti-ganglioside anti-idiotypic vaccination: more than molecular mimicry

Surgery, chemotherapy, and radiation therapy are standard modalities for cancer treatment, but the effectiveness of these treatments has reached a plateau. Thus, other strategies are being explored to combine with the current treatment paradigms in order to reach better clinical results. One of these approaches is the active immunotherapy based on the induction of anti-tumor responses by anti-idiotypic vaccination. This approach arose from Jerne’s idiotypic network theory, which postulates that B lymphocytes forms a functional network, with a role in the establishment of the immune repertoires, in the regulation of natural antibody production and even in the establishment of natural tolerance. Due to the large potential diversity of the immunoglobulin variable regions, the idiotypes repertoire can mimic the universe of self and foreign epitopes, even those of non-protein nature, like gangliosides. Gangliosides are sialic acid-containing glycolipids that have been considered attractive targets for cancer immunotherapy, based on the qualitative and quantitative changes they suffer during malignant transformation and due to their importance for tumor biology. Although any idiotype could be able to mimic any antigen, only those related to antigens involved in functions relevant for organism homeostasis, and that in consequence has been fixed by evolution, would be able not only to mimic, but also to activate the idiotypic cascades related with the nominal antigen. The present review updates the results, failures and hopes, obtained with ganglioside mimicking anti-idiotypic antibodies and presents evidences of the existence of a natural response against gangliosides, suggesting that these glycolipids could be idiotypically relevant antigens.

Idiotypes as immunogens: facing the challenge of inducing strong therapeutic immune responses against the variable region of immunoglobulins

Idiotype (Id)-based immunotherapy has been exploited as cancer treatment option. Conceived as therapy for malignancies bearing idiotypic antigens, it has been also extended to solid tumors because of the capacity of anti-idiotypic antibodies to mimic Id-unrelated antigens. In both these two settings, efforts are being made to overcome the poor immune responsiveness often experienced when using self immunoglobulins as immunogens. Despite bearing a unique gene combination, and thus particular epitopes, it is normally difficult to stimulate the immune response against antibody variable regions. Different strategies are currently used to strengthen Id immunogenicity, such as concomitant use of immune-stimulating molecules, design of Id-containing immunogenic recombinant proteins, specific targeting of relevant immune cells, and genetic immunization. This review focuses on the role of anti-Id vaccination in cancer management and on the current developments used to foster anti-idiotypic B and T cell responses.

Racotumomab: an anti-idiotype vaccine related to N-glycolyl-containing gangliosides - preclinical and clinical data

Neu-glycolyl (NeuGc)-containing gangliosides are attractive targets for immunotherapy with anti-idiotype mAbs, because these glycolipids are not normal components of the cytoplasmic membrane in humans, but their expression has been demonstrated in several human malignant tumors. Racotumomab is an anti-idiotype mAb specific to P3 mAb, an antibody which reacts to NeuGc-containing gangliosides, sulfatides, and other antigens expressed in tumors. Preparations containing racotumomab were able to induce a strong anti-metastatic effect in tumor-bearing mice. Different Phase I clinical trials have been conducted in patients with advanced melanoma, breast cancer, and lung cancer. The results of these clinical trials demonstrated the low toxicity and the high immunogenicity of this vaccine. The induced antibodies recognized and directly killed tumor cells expressing NeuGcGM3. A Phase II/III multicenter, controlled, randomized, double blind clinical trial was conducted to evaluate the effect of aluminum hydroxide-precipitated racotumomab vaccine in overall survival in patients with advanced non-small cell lung cancer. The clinical results of this study showed a significant clinical benefit in the patients who were treated with the anti-idiotype vaccine.

Immunotherapy of cancer in 2012

The immunotherapy of cancer has made significant strides in the past few years due to improved understanding of the underlying principles of tumor biology and immunology. These principles have been critical in the development of immunotherapy in the laboratory and in the implementation of immunotherapy in the clinic. This improved understanding of immunotherapy, enhanced by increased insights into the mechanism of tumor immune response and its evasion by tumors, now permits manipulation of this interaction and elucidates the therapeutic role of immunity in cancer. Also important, this improved understanding of immunotherapy and the mechanisms underlying immunity in cancer has fueled an expanding array of new therapeutic agents for a variety of cancers. Pegylated interferon-α2b as an adjuvant therapy and ipilimumab as therapy for advanced disease, both of which were approved by the United States Food and Drug Administration for melanoma in March 2011, are 2 prime examples of how an increased understanding of the principles of tumor biology and immunology have been translated successfully from the laboratory to the clinical setting. Principles that guide the development and application of immunotherapy include antibodies, cytokines, vaccines, and cellular therapies. The identification and further elucidation of the role of immunotherapy in different tumor types, and the development of strategies for combining immunotherapy with cytotoxic and molecularly targeted agents for future multimodal therapy for cancer will enable even greater progress and ultimately lead to improved outcomes for patients receiving cancer immunotherapy.

Current status of immunotherapy for the treatment of lung cancer

Immunotherapy is a novel approach for the treatment of systemic malignancies. Passive and adaptive immunotherapy have been applied to the treatment of a wide variety of solid tumors such as malignant melanoma (1), renal cell carcinoma (2) and ovarian cancer (3). Several early clinical trials of immune based therapy for both non-small (NSCLC) and small cell lung cancer (SCLC) have demonstrated limited or no success (3),(4) but recent trials of antigen-specific cancer immunotherapy have shown early therapeutic potential and are now being rigorously evaluated on a larger scale (5). In this communication we briefly review the historic aspects of immune based therapy for solid cancer, describe therapeutic strategies aimed at targeting lung cancer, and discuss limitations of current therapy and future directions of this field.