Mature autologous dendritic cell vaccines in advanced non-small cell lung cancer: a phase I pilot study

Production of dendritic cell vaccines using different methods with equivalent results: Implications for emerging centers

INTRODUCTION

Dendritic cell (DC) vaccines have demonstrated good efficacy in preventing relapse and in increasing survival of patients affected by a variety of both solid and hematological tumors. Most protocols used to generate these cells involve the automated separation of peripheral blood monocytes from patients. This approach requires specialized equipment, which elevates the cost of this type of therapy, potentially limiting the widespread access to patients.

METHOD

In this study, we compare the yield and quality of dendritic cells generated from monocytes and isolated by an automated method or by manual methods using gradient centrifugation.

RESULTS

The results demonstrate the equivalence of the 3 methods in relation to the yield and final quality of the product, however with considerable differences between the costs of these procedures. In addition, this study also demonstrates the feasibility of the antigenic pulse with autologous tumor cell lysates, constituting a source of antigens, not only easily obtained and manipulated, but also specific to the patient's tumor.

CONCLUSION

These findings may have important implications for emerging centers interested in using this medical approach and potentially increase the access of a greater number of patients to this therapeutic option.

Characteristics of tumor microenvironment and novel immunotherapeutic strategies for non-small cell lung cancer

Immune checkpoint inhibitor-based immunotherapy has revolutionized the treatment approach of non-small cell lung cancer (NSCLC). Monoclonal antibodies against programmed cell death-1 (PD-1) and PD-ligand 1 (PD-L1) are widely used in clinical practice, but other antibodies that can circumvent innate and acquired resistance are bound to undergo preclinical and clinical studies. However, tumor cells can develop and facilitate the tolerogenic nature of the tumor microenvironment (TME), resulting in tumor progression. Therefore, the immune escape mechanisms exploited by growing lung cancer involve a fine interplay between all actors in the TME. A better understanding of the molecular biology of lung cancer and the cellular/molecular mechanisms involved in the crosstalk between lung cancer cells and immune cells in the TME could identify novel therapeutic weapons in the old war against lung cancer. This article discusses the role of TME in the progression of lung cancer and pinpoints possible advances and challenges of immunotherapy for NSCLC.

Adoptive cell therapies in thoracic malignancies

Immunotherapy has gained great interest in thoracic malignancies in the last decade, first in non-small cell lung cancer (NSCLC), but also more recently in small-cell lung cancer (SCLC) and malignant pleural mesothelioma (MPM). However, while 15-20% of patients will greatly benefit from immune checkpoint blockers (ICBs), a vast majority will rapidly exhibit resistance. Reasons for this are multiple: non-immunogenic tumors, immunosuppressive tumor microenvironment or defects in immune cells trafficking to the tumor sites being some of the most frequent. Current progress in adoptive cell therapies could offer a way to overcome these hurdles and bring effective immune cells to the tumor site. In this review, we discuss advantages, limits and future perspectives of adoptive cell therapy (ACT) in thoracic malignancies from lymphokine-activated killer cells (LAK), cytokine-induced killer cells (CIK), natural killer cells (NK), dendritic cells (DC) vaccines and tumor-infiltrating lymphocytes (TILs) to TCR engineering and CARs. Trials are still in their early phases, and while there may still be many limitations to overcome, a combination of these different approaches with ICBs, chemotherapy and/or radiotherapy could vastly improve the way we treat thoracic cancers.

Field safety experience with an autologous cancer vaccine in tumor-bearing cats: a retrospective study of 117 cases (2015-2020)

OBJECTIVES

The aim of this study was to determine the frequency and severity of adverse events (AEs) reported from use of an adjuvanted whole-cell autologous cancer vaccine in cats with solid tumors under field conditions.

METHODS

The case accession database at Torigen Pharmaceuticals was searched to identify client-owned cats that underwent biopsy or surgical resection of their primary tumor, had histologic confirmation of neoplasia and received at least one subcutaneous dose of an adjuvanted whole-cell autologous cancer vaccine. Records were reviewed for any reported AEs.

RESULTS

In total, 117 cats met the inclusion criteria and received 422 doses of autologous cancer vaccine. Six (5.1%) cats had seven reported AEs, with the majority of these (85.7%) being characterized as grade 1 or 2 (mild) and resolving without medical intervention.

CONCLUSIONS AND RELEVANCE

AEs were infrequent in cats treated with an adjuvanted whole-cell autologous cancer vaccine under typical field use conditions. This form of active cancer immunotherapy appears to be well tolerated by cats and may represent a treatment option for owners who are concerned about AEs associated with chemotherapy or radiotherapy. Additional studies are warranted to determine the efficacy of this form of individualized immunotherapy in cats with solid tumors.

Safety and efficacy of dendritic cell-based immunotherapy (DCVAC/LuCa) combined with carboplatin/pemetrexed for patients with advanced non-squamous non-small-cell lung cancer without oncogenic drivers

Background

Our prospective, open-label, single-arm phase II study investigated the safety and efficacy of DCVAC/LuCa (dendritic cell vaccines for lung cancer) combined with standard carboplatin/pemetrexed in advanced non-squamous (nsq) non-small-cell lung cancer (NSCLC).

Patients and methods

Eligible patients had stage IV nsq NSCLC without oncogenic drivers and had not received prior systemic cancer therapy. Treatment consisted of carboplatin/pemetrexed for up to 6 cycles followed by 21 cycles of pemetrexed maintenance or until progression or intolerance. Non-progression patients after two cycles of chemotherapy started to receive DCVAC/LuCa subcutaneously (s.c.) on day 15 of cycle 3, and thereafter q3w (day 15 of chemotherapy cycles) for up to 15 doses. Dosing of DCVAC/LuCa s.c. varied among patients depending on the baseline number of leucocytes but remained constant for each single patient. Safety was assessed by adverse events (AEs), treatment-related adverse events (TRAEs), serious adverse events (SAEs), and adverse events of special interest (AESIs). Efficacy was measured by overall survival (OS), progression-free survival (PFS), time to progression (TTP), and objective response rate (ORR).

Results

Sixty-one patients were enrolled. In the safety population (n = 60), eight patients (13.33%) had grade 3 or greater TRAEs, and six patients (10.0%) showed SAEs which were not related to leukapheresis or DC vaccination. Six grade 1 AEs were considered to be related to leukapheresis. No AESIs or DCVAC/LuCa-induced AEs were observed. The 2-year survival rate in the modified intention-to-treat population (n = 44) was 52.57%. Median OS was not reached. Median PFS was 8.0 months, median TTP was 10.2 months, and the ORR was 31.82%.

Conclusion

In treatment-naïve stage IV nsq NSCLC patients without oncogenic drivers, the combination of carboplatin/pemetrexed and DCVAC/LuCa was well tolerated and showed promising efficacy. Therefore, a study to prove our immunotherapeutic concept in a randomized phase III trial is planned.

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We investigated the safety and efficacy of DCVAC/LuCa combined with standard carboplatin/pemetrexed in nsq NSCLC.

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The combination therapy showed a favorable tolerability profile in a selected Chinese population.

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The 2-year survival rate in the modified intention-to-treat population (n = 44) was 52.57%.

Recent Advances and Future Perspective of DC-Based Therapy in NSCLC

Current treatment for patients with non-small-cell lung cancer (NSCLC) is suboptimal since therapy is only effective in a minority of patients and does not always induce a long-lasting response. This highlights the importance of exploring new treatment options. The clinical success of immunotherapy relies on the ability of the immune system to mount an adequate anti-tumor response. The activation of cytotoxic T cells, the effector immune cells responsible for tumor cell killing, is of paramount importance for the immunotherapy success. These cytotoxic T cells are primarily instructed by dendritic cells (DCs). DCs are the most potent antigen-presenting cells (APCs) and are capable of orchestrating a strong anti-cancer immune response. DC function is often suppressed in NSCLC. Therefore, resurrection of DC function is an interesting approach to enhance anti-cancer immune response. Recent data from DC-based treatment studies has given rise to the impression that DC-based treatment cannot induce clinical benefit in NSCLC by itself. However, these are all early-phase studies that were mainly designed to study safety and were not powered to study clinical benefit. The fact that these studies do show that DC-based therapies were well-tolerated and could induce the desired immune responses, indicates that DC-based therapy is still a promising option. Especially combination with other treatment modalities might enhance immunological response and clinical outcome. In this review, we will identify the possibilities from current DC-based treatment trials that could open up new venues to improve future treatment.

Dendritic Cell-Based Immunotherapy in Lung Cancer

Lung cancer remains the leading cause of cancer-related death worldwide. The advent of immune checkpoint inhibitors has led to a paradigm shift in the treatment of metastatic non-small cell and small cell lung cancer. However, despite prolonged overall survival, only a minority of the patients derive clinical benefit from these treatments suggesting that the full anti-tumoral potential of the immune system is not being harnessed yet. One way to overcome this problem is to combine immune checkpoint blockade with different strategies aimed at inducing or restoring cellular immunity in a tumor-specific, robust, and durable way. Owing to their unique capacity to initiate and regulate T cell responses, dendritic cells have been extensively explored as tools for immunotherapy in many tumors, including lung cancer. In this review, we provide an update on the nearly twenty years of experience with dendritic cell-based immunotherapy in lung cancer. We summarize the main results from the early phase trials and give an overview of the future perspectives within this field.

Immune cell engineering: opportunities in lung cancer therapeutics

Engineered immune cells offer a prime therapeutic alternate for some aggressive and frequently occurring malignancies like lung cancer. These therapies were reported to result in tumor regression and overall improvement in patient survival. However, studies also suggest that the presence of cancer cell-induced immune-suppressive microenvironment, off-target toxicity, and difficulty in concurrent imaging are some prime impendent in the success of these approaches. The present article reviews the need and significance of the currently available immune cell-based strategies for lung cancer therapeutics. It also showcases the utility of incorporating nanoengineered strategies and details the available formulations of nanocarriers. In last, it briefly discussed the existing methods for nanoparticle fuctionalization and challenges in translating basic research to the clinics. Graphical Abstract.

Dendritic cell/cytokine-induced killer cell-based immunotherapy in lung cancer: What we know and future landscape

Multiple modalities for lung cancer therapy have emerged in the past decade, whereas their clinical applications and survival-beneficiary is little known. Vaccination with dendritic cells (DCs) or DCs/cytokine-induced killer (CIK) cells has shown limited success in the treatment of patients with advanced non-small-cell lung cancer. To evaluate and overcome these limitations in further studies, in the present review, we sum up recent progress about DCs or DCs/CIKs-based approaches for preclinical and clinical trials in patients with lung cancer and discuss some of the limited therapeutic success. Moreover, this review highlights the need to focus future studies on the development of new approaches for successful immunotherapy in patients with lung cancer.

Immunogenicity of mammary tumor cells can be induced by shikonin via direct binding-interference with hnRNPA1

Immunogenic cell death (ICD) of tumor cells occurs via various pathways that activate immune cell systems against cancer. Previous studies have demonstrated that shikonin (SK), a plant secondary metabolite, can confer strong pharmacological activities that activate ICD and strong immunogenicity of tumor cells. However, the exact hierarchical regulatory mechanisms including the molecular targets of SK-activated immunogenicity are still unknown. Here, the heterogeneous nuclear ribonucleoprotein A1 (hnRNPA1) was revealed to serve as a specific protein target for SK. This binding plays a key role in SK-stimulated ICD activity and the suppression of post-transcriptional mRNA processing, including nuclear export activity of newly synthesized mRNAs in mammary carcinoma cells in vitro. Moreover, it also mechanistically mediates the anti-metastatic effect of a tumor cell lysate (TCL) vaccine, which can be readily generated from SK-treated 4T1 tumor cells (SK-TCL), and the derived tumor-immunogenicity of SK-TCL-treated dendritic cells in vivo. Together, the identification of hnRNPA1 as the intracellular molecular target provides compelling pharmacology-based knowledge for the potential clinical use of SK-induced immunogenicity. In addition, SK may also serve as a potent suppressor that interferes with specific post-transcriptional activities, a mechanism which may be useful for exploitation in cancer therapeutics.

Cellular immunotherapy of cancer: an overview and future directions

The clinical success of checkpoint inhibitors has led to a renaissance of interest in cancer immunotherapies. In particular, the possibility of ex vivo expanding autologous lymphocytes that specifically recognize tumor cells has attracted much research and clinical trial interest. In this review, we discuss the historical background of tumor immunotherapy using cell-based approaches, and provide some rationale for overcoming current barriers to success of autologous immunotherapy. An overview of adoptive transfer of lymphocytes, tumor infiltrating lymphocytes and dendritic cell therapies is provided. We conclude with discussing the possibility of gene-manipulating immune cells in order to augment therapeutic activity, including silencing of the immune-suppressive zinc finger orphan nuclear receptor, NR2F6, as an attractive means of overcoming tumor-associated immune suppression.

Generation of dendritic cell-based vaccine using high hydrostatic pressure for non-small cell lung cancer immunotherapy

High hydrostatic pressure (HHP) induces immunogenic death of tumor cells which confer protective anti-tumor immunity in vivo. Moreover, DC pulsed with HHP-treated tumor cells induced therapeutic effect in mouse cancer model. In this study, we tested the immunogenicity, stability and T cell stimulatory activity of human monocyte-derived dendritic cell (DC)-based HHP lung cancer vaccine generated in GMP compliant serum free medium using HHP 250 MPa. DC pulsed with HHP-killed lung cancer cells and poly(I:C) enhanced DC maturation, chemotactic migration and production of pro-inflammatory cytokines after 24h. Moreover, DC-based HHP lung cancer vaccine showed functional plasticity after transfer into serum-containing media and stimulation with LPS or CD40L after additional 24h. LPS and CD40L stimulation further differentially enhanced the expression of costimulatory molecules and production of IL-12p70. DC-based HHP lung cancer vaccine decreased the number of CD4+CD25+Foxp3+ T regulatory cells and stimulated IFN-γ-producing tumor antigen-specific CD4+ and CD8+ T cells from non-small cell lung cancer (NSCLC) patients. Tumor antigen specific CD8+ and CD4+ T cell responses were detected in NSCLC patient's against a selected tumor antigens expressed by lung cancer cell lines used for the vaccine generation. We also showed for the first time that protein antigen from HHP-killed lung cancer cells is processed and presented by DC to CD8+ T cells. Our results represent important preclinical data for ongoing NSCLC Phase I/II clinical trial using DC-based active cellular immunotherapy (DCVAC/LuCa) in combination with chemotherapy and immune enhancers.

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.

Identification of suitable reference genes for gene expression studies using quantitative polymerase chain reaction in lung cancer in vitro

The present study aimed to examine 10 housekeeping genes (HKGs), including 18s ribosomal RNA (18S), glyceraldehyde‑3‑phosphate dehydrogenase (GAPDH), ribosomal protein large P0 (RPLP0), β‑actin (ACTB), peptidylprolyl isomerase A (PPIA), phosphoglycerate kinase‑1 (PGK1), β‑2‑microglobulin (B2M), ribosomal protein LI3a (RPL13A), hypoxanthine phosphoribosyl transferase‑1 (HPRT1) and TATA box binding protein (TBP) in order to identify the most stable and suitable reference genes for use in expression studies in non‑small cell lung cancer. The mRNA expression encoding the panel of the 10 HKGs was determined using reverse transcription‑quantitative PCR (RT‑qPCR) in human lung cancer cell lines. Three software programs, BestKeeper, NormFinder and geNorm, were used to ascertain the most suitable reference genes to normalize the RNA input. The present study examined three lung cancer cell lines (A549, NCI‑H446 and NCI‑H460). The analysis of the experimental data using BestKeeper software revealed that all 10 HKGs were stable, with GADPH, followed by 18S being the most stable genes and PPIA and HPRT1 being the least stable genes. The NormFinder software results demonstrated that PPIA followed by ACTB were the most stable and B2M and RPLP0 were the least stable. The geNorm software results revealed that ACTB and PGK1, followed by PPIA were the most stable genes and B2M and RPLP0 were identified as the least stable genes. Due to discrepancies in the ranking orders of the reference genes obtained by different analyzing software programs, it was not possible to determine a single universal reference gene. The suitability of selected reference genes requires unconditional validation prior to each study. Based on the three analyzing programs, ACTB, PPIA and PGK1 were the most stable reference genes in lung cancer cell lines.

Exogenous addition of arachidonic acid to the culture media enhances the functionality of dendritic cells for their possible use in cancer immunotherapy

The development of dendritic cell based vaccines is a promising approach in cancer immunotherapy. For their successful use in the clinics, the propagation and functionality of DCs is crucial. We earlier established a two-step method for the large scale generation of DCs from umbilical cord blood derived MNCs/CD34+ cells. This work aims at improving their functionality based on the following observations: in vitro generated DCs can be less efficient in migration and other functional activities due to lower eicosanoid levels. The production of eicosanoids from Arachidonic Acid (AA) can be hampered due to suppression of the enzyme phospholipase A2 by IL-4, an essential cytokine required for the differentiation of DCs. We hypothesized that exogenous addition of AA to the culture media during DC generation may result in DCs with improved functionality. DCs were generated with and without AA. The two DC sets were compared by phenotypic analysis, morphology and functional assays like antigen uptake, MLR, CTL assay and in vitro and in vivo migration. Though there were no differences between the two types of DCs in terms of morphology, phenotype and antigen uptake, AA⁺ DCs exhibited an enhanced in vitro and in vivo migration, T cell stimulatory capacity, CTL activity and significantly higher transcript levels of COX-2. AA⁺ DCs also show a favorable Th1 cytokine profile than AA^- DCs. Thus addition of AA to the culture media is skewing the DCs towards the secretion of more IL-12 and less of IL-10 along with the restoration of eicosanoids levels in a COX-2 mediated pathway thereby enhancing the functionality of these cells to be used as a potent cellular vaccine. Taken together, these findings will be helpful in the better contriving of DC based vaccines for cancer immunotherapy.

Trial watch: Dendritic cell-based interventions for cancer therapy

Dendritic cells (DCs) occupy a central position in the immune system, orchestrating a wide repertoire of responses that span from the development of self-tolerance to the elicitation of potent cellular and humoral immunity. Accordingly, DCs are involved in the etiology of conditions as diverse as infectious diseases, allergic and autoimmune disorders, graft rejection and cancer. During the last decade, several methods have been developed to load DCs with tumor-associated antigens, ex vivo or in vivo, in the attempt to use them as therapeutic anticancer vaccines that would elicit clinically relevant immune responses. While this has not always been the case, several clinical studies have demonstrated that DC-based anticancer vaccines are capable of activating tumor-specific immune responses that increase overall survival, at least in a subset of patients. In 2010, this branch of clinical research has culminated with the approval by FDA of a DC-based therapeutic vaccine (sipuleucel-T, Provenge^®) for use in patients with asymptomatic or minimally symptomatic metastatic hormone-refractory prostate cancer. Intense research efforts are currently dedicated to the identification of the immunological features of patients that best respond to DC-based anticancer vaccines. This knowledge may indeed lead to personalized combination strategies that would extend the benefit of DC-based immunotherapy to a larger patient population. In addition, widespread enthusiasm has been generated by the results of the first clinical trials based on in vivo DC targeting, an approach that holds great promises for the future of DC-based immunotherapy. In this Trial Watch, we will summarize the results of recently completed clinical trials and discuss the progress of ongoing studies that have evaluated/are evaluating DC-based interventions for cancer therapy.

Human IP10-scFv and DC-induced CTL synergistically inhibit the growth of glioma in a xenograft model

The epidermal growth factor receptor (EGFR) mutant of EGFRvIII is highly expressed in glioma cells, and the EGFRvIII-specific dendritic cell (DC)-induced tumor antigen-specific CD8(+) cytotoxic T lymphocytes (CTLs) may hold promise in cancer immunotherapy. Interferon (IFN)-γ-inducible protein (IP)-10 (IP-10) is a potent inhibitor of angiogenesis and can recruit CXCR3(+) T cells, including CD8(+) T cells, which are important for the control of tumor growth. In this study, we assessed if the combination of IP10-EGFRvIIIscFv with DC-induced CTLs would improve the therapeutic antitumor efficacy. IP10-scFv was generated by linking the human IP-10 gene with the DNA fragment for anti-EGFRvIIIscFv with a (Gly4Ser)3 flexible linker, purified by affinity chromatography, and characterized for its anti-EGFRvIII immunoreactivity and chemotactic activity. DCs were isolated from human peripheral blood monocyte cells and pulsed with EGFRvIII-peptide, then co-cultured with autologous CD8(+) T cells. BALB/c-nu mice were inoculated with human glioma U87-EGFRvIII cells in the brain and treated intracranially with IP10-scFv and/or intravenously with DC-induced CTLs for evaluating the therapeutic effect. Treatment with both IP10-scFv and EGFRvIII peptide-pulsed, DC-induced CTL synergistically inhibited the growth of glioma and prolonged the survival of tumor-bearing mice, which was accompanied by the inhibition of tumor angiogenesis and enhancement of cytotoxicity, thereby increasing the numbers of brain-infiltrating lymphocytes (BILs) and prolonging the residence time of CTLs in the tumor.

Pemetrexed plus dendritic cells as second-line treatment for patients with stage IIIB/IV non-small cell lung cancer who had treatment with TKI

The aim of this study was to determine the efficacy and toxicity of pemetrexed plus dendritic cells (DCs) in patients suffering from stage IIIB or IV lung adenocarcinoma, who had undergone maintenance treatment with gefitinib or erlotinib. Patients who had failed gefitinib or erlotinib maintenance treatment had ECOG performance statuses ranging from 0 to 2.27 patients received pemetrexed plus DCs as second-line treatment. Dosage: 500 mg/m(2) pemetrexed was administered on day 1 of a 21-day cycle. DCs were given for one cycle of 21 days. Three patients (11.1 %) experienced a partial response and 14 patients (51.9 %) showed stable disease. Ten patients (37.0 %) had progressive disease. The median time to progression-free survival (PFS) was 4.8 months [95 % confidence interval (CI) 4.4-5.2], and the median overall survival was 10.7 months (95 % CI 10.3-11.2). In the subgroup analysis, PFS had a significant difference between the low ratio of CD4/CD8 and normal ratio of CD4/CD8, with 4.5 months (95 % CI 4.2-4.9) and 5.0 months (95 % CI 4.5-5.7), (Log Rank = 0.039), respectively. No one patient experienced grade 4 toxicity. A regimen of pemetrexed combined with DCs is marginally effective and well tolerated in patients with stage IIIB or IV lung adenocarcinoma who had received gefitinib or erlotinib first-line treatment.

A review of dendritic cell therapy for cancer: progress and challenges

Dendritic cells are the professional antigen-presenting cells of the innate immune system with the potential to generate robust antigen-specific T cell immune responses. Immunotherapeutic strategies have attempted to monopolize on this ability of dendritic cells to deliver antigens as a means of therapeutic vaccination in individuals with advanced malignancies. Since the publication of the first clinical trial in melanoma patients in 1995, therapeutic dendritic cell cancer vaccines have been extensively studied in numerous phase I and II trials. While advances have been encountered (especially with prostate cancer), there are still considerable challenges that need to be addressed in future clinical trials. In this review, we describe the current methodology and highlight trials which have contributed to the development of dendritic cell vaccines. We then review strategies to optimize dendritic cell vaccines in order to improve antitumor responses in cancer patients.

Tracking cellular and immune therapies in cancer

The field of tumor immunology has seen an explosion of renewed interest over the last decade. With the FDA approval of new immunotherapies for prostate cancer and melanoma, as well as several exciting new drugs in clinical trials, tumor immunology is becoming an increasingly important topic in preclinical studies and patient care. However, the current methods for assessing the immune status of a patient and tumor are limited, which has led to the development of novel molecular imaging methods for assessing tumor immunology. From cell tracking for cellular therapeutics to assessing the tumor immune microenvironment, these imaging methods have the potential to further preclinical understanding of immunotherapies and potentially translate into clinically useful tests to predict and assess therapeutic response of these exciting new agents. In this review, we first discuss the recent advances in cancer immunotherapy, followed by a detailed review of the current state of molecular imaging for tumor immunology. Finally, we discuss opportunities for further development and innovation in this rapidly growing field.

Recent progress in peptide vaccination in cancer with a focus on non-small-cell lung cancer

Active immunotherapy aimed at the stimulation of tumor-specific T cells has established itself within the clinic as a therapeutic option to treat cancer. One strategy is the use of so-called peptides that mimic genuine T-cell epitopes as vaccines to activate tumor-specific T cells. In various clinical trials, different types of vaccines, adjuvants and other immunomodulatory compounds were evaluated in patients with different types of tumors. Here, we review the trials published in the last 3 years focusing on the T-cell response, the effect of immunomodulation and potential relationships with clinical outcomes. Furthermore, we would like to make a case for the development of peptide vaccines aiming to treat non-small-cell lung cancer, the most common cause of cancer mortality.

Cancer targeting vaccines: surrogate measures of activity

Recent FDA approval of sipuleucel-T and Ipilimumab as indicated immunologic therapy in patients with advanced prostate cancer and melanoma, respectively, has established a foothold for broader utilization of vaccine based technology in managing cancer.  Despite difficulty of cell harvest and processing with sipuleucel-T and modest toxicity to Ipilimumab, when matched up with the appropriate cancer patient these immunologic approaches have provided significant benefit and have stimulated exciting forward progress in the development of new potent and less toxic (more targeted) vaccines.  However, surrogate measures of activity to optimally define more sensitive subset populations and to determine length of treatment time in order to optimize management with other treatment options remain elusive.  Key clinically tested vaccines under development which demonstrate correlation of patient benefit to induced immune responsiveness will be discussed.  Results suggest with some vaccines correlation of patient benefit and surrogate measures of activity actually do exist.  Examples will be discussed.

Improving lung cancer survival; time to move on

BACKGROUND

During the past decades, numerous efforts have been made to decrease the death rate among lung cancer patients. Nonetheless, the improvement in long-term survival has been limited and lung cancer is still a devastating disease.

DISCUSSION

With this article we would like to point out that survival of lung cancer could be strongly improved by controlling two pivotal prognostic factors: stage and treatment. This is corresponding with recent reports that show a decrease in lung cancer mortality by screening programs. In addition, modulation of the patient's immune system by immunotherapy either as monotherapy or combined with conventional cancer treatments offers the prospect of tailoring treatments much more precisely and has also been shown to lead to a better response to treatment and overall survival of non-small cell lung cancer patients.

SUMMARY

Since only small improvements in survival can be expected in advanced disease with the use of conventional therapies, more research should be focused on lung cancer screening programs and patient tailored immunotherapy with or without conventional therapies. If these approaches are clinically combined in a standard multidisciplinary policy we might be able to advance the survival of patients with lung cancer.

Impact of dendritic cell vaccines pulsed with Wilms' tumour-1 peptide antigen on the survival of patients with advanced non-small cell lung cancers

PURPOSE

Dendritic cell (DC)-based vaccines have been expected to serve as new therapeutic approaches for advanced non-small cell lung cancers (NSCLCs); however, their clinical outcomes have not been fully elucidated. We report a single-centre clinical study analysing factors affecting the survival of patients with advanced NSCLCs who received DC vaccines pulsed with or without Wilms' tumour protein-1 (WT1) peptide.

METHODS

Among 62 patients with previously treated inoperable or postoperatively relapsed NSCLCs who met the inclusion criteria, DCs from 47 (76%) patients who showed HLA-A2402/0201/0206 were pulsed with one or more corresponding WT1 peptide antigens. DC vaccines were intradermally injected biweekly.

RESULTS

Clinical responses based on response evaluation criteria in solid tumours (RECIST) were found in 31 (50%) patients at 3 months after the first DC vaccine (complete response: 1 (1.6%), partial response: 4 (6.5%), stable disease: 26 (41.9%)). Median survival time was 27 months (82% in 1 year and 54% in 2 years) from initial diagnosis, and that was 12 months (48% in 1 year and 22% in 2 years) from the first DC vaccination. Importantly, multivariate analyses revealed that only two factors, blood haemoglobin and the use of WT1 peptides, significantly affected the overall survival of patients from both initial diagnosis and first vaccination.

CONCLUSIONS

This study is the first to suggest that DC vaccines pulsed with WT1 may hold a significant impact to prolong the overall survival of patients with advanced NSCLCs.

Patient-tailored modulation of the immune system may revolutionize future lung cancer treatment

Cancer research has devoted most of its energy over the past decades on unraveling the control mechanisms within tumor cells that govern its behavior. From this we know that the onset of cancer is the result of cumulative genetic mutations and epigenetic alterations in tumor cells leading to an unregulated cell cycle, unlimited replicative potential and the possibility for tissue invasion and metastasis. Until recently it was often thought that tumors are more or less undetected or tolerated by the patient’s immune system causing the neoplastic cells to divide and spread without resistance. However, it is without any doubt that the tumor environment contains a wide variety of recruited host immune cells. These tumor infiltrating immune cells influence anti-tumor responses in opposing ways and emerges as a critical regulator of tumor growth. Here we provide a summary of the relevant immunological cell types and their complex and dynamic roles within an established tumor microenvironment. For this, we focus on both the systemic compartment as well as the local presence within the tumor microenvironment of late-stage non-small cell lung cancer (NSCLC), admitting that this multifaceted cellular composition will be different from earlier stages of the disease, between NSCLC patients. Understanding the paradoxical role that the immune system plays in cancer and increasing options for their modulation may alter the odds in favor of a more effective anti-tumor immune response. We predict that the future standard of care of lung cancer will involve patient-tailor-made combination therapies that associate (traditional) chemotherapeutic drugs and biologicals with immune modulating agents and in this way complement the therapeutic armamentarium for this disease.

Strengths and weaknesses of immunotherapy for advanced non-small-cell lung cancer: a meta-analysis of 12 randomized controlled trials

Background

Lung cancer is one of the leading causes of cancer death worldwide. Non-small-cell lung cancer (NSCLC) accounts for approximately 85% of all lung cancers. Immunotherapy has yielded no consistent benefit to date for those patients. Assessing the objective efficacy and safety of immunotherapy for advanced NSCLC patients will help to instruct the future development of immunotherapeutic drugs.

Methodology and Principal Findings

We performed a meta-analysis of 12 randomized controlled trials including 3134 patients (1570 patients in the immunotherapy group and 1564 patients in the control group) with histologically confirmed stage IIIA, IIIB, or IV NSCLC. The analysis was executed with efficacy end points regarding overall survival (OS), progression-free survival (PFS), complete response (CR), partial response (PR), and total effective rate. Overall unstratified OS, PFS, PR, and total effective rate were significantly improved in advanced NSCLC patients in the immunotherapy group (P = 0.0007, 0.0004, 0.002, 0.003, respectively), whereas CR was not improved (P = 0.97). Subgroup analysis showed that monoclonal antibody (mAb) immunotherapy significantly improved the PFS, PR, and total effective rate and showed a trend of improving OS of advanced NSCLC patients compared with the control group, with one kind of adverse event being significantly dominant. Compared with the control group, the vaccine subgroup showed no significant difference with regard to serious adverse events, whereas cytokine immunotherapy significantly induced three kinds of serious adverse events.

Conclusions

Immunotherapy works efficiently on advanced NSCLC patients. Of several immunotherapies, mAb therapy may be a potential immunotherapy for advanced NSCLC patients, and become a standard complementary therapeutic approach in the future if the issues concerning toxicity and allergenicity of mAbs have been overcome.