Prospective randomized trial of high-dose interleukin-2 alone or in conjunction with lymphokine-activated killer cells for the treatment of patients with advanced cancer

The challenges and molecular approaches surrounding interleukin-2-based therapeutics in cancer

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IL2-based cancer therapies are limited by their toxicity and pleiotropy.

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Current engineering approaches target IL2 half-life and cell/receptor specificity.

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IL2 may enhance the efficacy of checkpoint inhibitors and CAR-T-based therapies.

Interleukin-2 has had a long history as a promising cancer therapeutic, being capable of eliciting complete and durable remissions in patients with metastatic renal cell carcinoma and metastatic melanoma. Despite high toxicity and efficacy limited to only certain patient subpopulations and cancer types, the prospective use of novel, engineered IL2 formats in combination with the presently expanding repertoire of immuno-oncological targets remains very encouraging. This is possible due to the significant research efforts in the IL2 field that have yielded critical structural and biological insights that have made IL2 more effective and more broadly applicable in the clinic. In this review, we discuss some of the molecular approaches that have been used to further improve IL2 therapy for cancer.

Overcoming Resistance to Natural Killer Cell Based Immunotherapies for Solid Tumors

Despite advances in the diagnostic and therapeutic modalities, the prognosis of several solid tumor malignancies remains poor. Different factors associated with solid tumors including a varied genetic signature, complex molecular signaling pathways, defective cross talk between the tumor cells and immune cells, hypoxic and immunosuppressive effects of tumor microenvironment result in a treatment resistant and metastatic phenotype. Over the past several years, immunotherapy has emerged as an attractive therapeutic option against multiple malignancies. The unique ability of natural killer (NK) cells to target cancer cells without antigen specificity makes them an ideal candidate for use against solid tumors. However, the outcomes of adoptive NK cell infusions into patients with solid tumors have been disappointing. Extensive studies have been done to investigate different strategies to improve the NK cell function, trafficking and tumor targeting. Use of cytokines and cytokine analogs has been well described and utilized to enhance the proliferation, stimulation and persistence of NK cells. Other techniques like blocking the human leukocyte antigen-killer cell receptors (KIR) interactions with anti-KIR monoclonal antibodies, preventing CD16 receptor shedding, increasing the expression of activating NK cell receptors like NKG2D, and use of immunocytokines and immune checkpoint inhibitors can enhance NK cell mediated cytotoxicity. Using genetically modified NK cells with chimeric antigen receptors and bispecific and trispecific NK cell engagers, NK cells can be effectively redirected to the tumor cells improving their cytotoxic potential. In this review, we have described these strategies and highlighted the need to further optimize these strategies to improve the clinical outcome of NK cell based immunotherapy against solid tumors.

Update on the biology and management of renal cell carcinoma

Renal cell cancer (RCC) (epithelial carcinoma of the kidney) represents 2%-4% of newly diagnosed adult tumors. Over the past 2 decades, RCC has been better characterized clinically and molecularly. It is a heterogeneous disease, with multiple subtypes, each with characteristic histology, genetics, molecular profiles, and biologic behavior. Tremendous heterogeneity has been identified with many distinct subtypes characterized. There are clinical questions to be addressed at every stage of this disease, and new targets being identified for therapeutic development. The unique characteristics of the clinical presentations of RCC have led to both questions and opportunities for improvement in management. Advances in targeted drug development and understanding of immunologic control of RCC are leading to a number of new clinical trials and regimens for advanced disease, with the goal of achieving long-term disease-free survival, as has been achieved in a proportion of such patients historically. RCC management is a promising area of ongoing clinical investigation.

Emerging Strategies in Systemic Therapy for the Treatment of Melanoma

Recent years have seen major improvements in survival of patients with advanced melanoma with the advent of various novel systemic immunotherapies and targeted therapies. As our understanding of these agents and their various mechanisms of action improves, even more impressive outcomes are being achieved through use of various combination strategies, including the combining of different immunotherapies with one another as well as with other modalities. However, despite the improved outcomes that have been achieved in advanced melanoma, responses to treatment are heterogeneous and may not always be durable. Additional advances in therapy are required, and several emerging strategies are a focus of interest. These include the investigation of several new immunotherapy and/or targeted therapy combinations, such as checkpoint inhibitors (anti-PD-1/anti-CTLA-4) with other immunotherapies (e.g., indoleamine 2,3 dioxygenase [IDO] inhibitors, antilymphocyte activation 3 [anti-LAG-3], histone deacetylase [HDAC] inhibitors, Toll-like receptor 9 [TLR-9] agonists, antiglucocorticoid-induced tumor necrosis factor receptor [anti-GITR], pegylated interleukin-2 [IL-2]), combined targeted therapies (e.g., MEK and CDK4/6 coinhibition), and combined immunotherapy and targeted therapy (e.g., the triplet combination of BRAF/MEK inhibition with anti-PD-1s). The identification of novel therapeutic targets in the MAP kinase pathway also offers opportunities to improve outcomes by overcoming de novo and acquired resistance to BRAF/MEK inhibition (e.g., the development of ERK inhibitors). In addition, adoptive cell transfer, the infusion of large numbers of activated autologous lymphocytes, may have a potential role in patients whose disease has progressed after immunotherapy. Taken together, these new approaches offer further potential to increase systemic treatment options and improve long-term outcomes for patients with advanced melanoma.

Immunotherapy in aggressive B-cell lymphomas

The idea that the immune system could be co-opted to treat cancer is not new; it has existed for centuries. However, what is new is the advancement of our understanding of how the immune system is regulated and how a tumor evolves to evade an immune response. This knowledge, combined with modern technologies to manipulate the immune system, both pharmacologically and genetically, has led to the realization of immuno-oncology as a new frontier in cancer therapeutics. This review will focus on pharmacologic immunotherapies in aggressive B cell lymphomas: checkpoint inhibition and bispecific antibodies. The success of checkpoint inhibitors in this heterogenous collection of diseases has largely been limited to those that genetic aberrations involving genes for checkpoint ligands, whereas bispecific antibodies appear to be more broadly efficacious but responses are short-lived. Investigation into the tumor microenvironment for each of the aggressive B cell lymphoma histologies, and interrogation of mechanisms of resistance as well as predictors of response to these immunotherapy approaches, will undoubtedly identify rational combinations as well as new therapeutic targets such that outcomes can be improved across these diseases.

The Latest Cancer Agents and Their Complications

The latest cancer agents, collectively known as cancer immunotherapy, have tremendously increased the armamentarium against cancer. Their targeted mechanisms seem ideal, but they do come with complications. As these therapies become more widespread, emergency physicians everywhere must be aware of the immune-related adverse events that can occur, and be ready to identify and coordinate treatment. This article provides the emergency physician with a brief introduction and overview of immunotherapy drugs and their complications.

Liver Metastases from Gastric Carcinoma: Report of a Patient Treated with Adoptive Immunotherapy (Tumor-Infiltrating Lymphocytes plus Interleukin-2 and Subsequently Local-Regional Lymphokine-Activated Killer Cells plus inTerleukin-2)

A 37-year-old patient with liver metastases from gastric cancer was treated with a double adoptive immunotherapy regimen comprising tumor-infiltrating lymphocytes plus interleukin-2 and subsequently local-regional lymphokine-activated killer cells plus interleukin-2 because of an extremely high in vitro cytotoxic specific activity on established gastric cancer cell lines. The necrosis verified in the center of the hepatic metastasis would appear to demonstrate treatment efficacy, but no clinical response was seen. In vitro cytotoxicity data alone are insufficient to predict the clinical efficacy of adoptive immunotherapy.

Renal Cancer Treatment: A Review of the Literature

Renal carcinoma represents about 3% of all adult tumors, with an estimate of 31,900 new cases diagnosed in 2003 in the United States. In the early phase of its natural history, renal cancer is potentially curable by surgery, but if the disease presents any signs of metastasis, the chances of survival are remote, even though anecdotal cases characterized by long survival have been reported. In fact, the treatment of metastatic renal cancer remains unsatisfactory. Systemic treatment with single agents and with polychemotherapy, with or without cytokine-based immunotherapy, has not been successful, obtaining very low response rates without a significant benefit in overall survival. This review highlights the most interesting issues regarding conventional therapeutic strategies, in localized and in advanced disease. New approaches such as monoclonal antibodies, vaccines, gene therapy, angiogenesis inhibitors and allogeneic cell transplantation and their possible clinical applications are also discussed.

Tumor Infiltrating Lymphocytes and Continuous Infusion Interleukin-2 after Metastasectomy in 61 Patients with Melanoma, Colorectal and Renal Carcinoma

AIMS AND BACKGROUND

Adoptive immunotherapy with tumor infiltrating lymphocyte (TIL) reinfusion plus continuous interleukin-2 (IL-2) infusion could represent an innovative way of treating immunogenic tumors. This study therefore recruited melanoma, colorectal and renal carcinoma patients whose metastases had been surgically removed.

STUDY DESIGN

The treatment was initially given to 22 patients with advanced disease and more recently to 39 disease-free (DF) patients after radical metastasectomy. The latter group was selected in view of a theoretically better lymphocyte/tumor cell ratio and with the aim to improve disease-free and overall survival (DFS-OS) in very high risk patients. The starting IL-2 dose was 12 MIU/day (West's schedule); doses were modulated on the bases of toxicity parameters. Even though patients received different total amounts of IL-2, all of them completed the treatment.

RESULTS

The treatment was offered to 22 advanced-stage cancer patients (12 melanomas, 9 colorectal carcinomas, 1 kidney carcinoma). Few and short stabilizations were observed with a median survival of 12 months (range, 3-29). Subsequently, another 39 patients were treated in an adjuvant setting after radical metastasectomy (18 melanomas, 19 colorectal carcinomas, 2 kidney cancers). Eleven out of 17 DF melanoma patients (64.7%) are still free of disease after a median of 37+ months (range, 5+ - 69+). In the group of DF colorectal cancer patients eight (44.4%) are still DF after a median of 21+ months (range, 7+ - 67+ months). One of the two patients with kidney cancer is still DF after 28+ months. Two patients (1 melanoma and 1 colorectal cancer) had just been treated and were therefore not evaluable. Severe toxicity occurred in three cases but was rapidly resolved. There was a great diversity in IL-2 doses administered; comparison of the total IL-2 dose administered between the patients who are still DF and those who progressed revealed no difference between the two groups of colorectal cancer patients, whereas melanoma patients who progressed received an average IL-2 dose of 6.5 MIU/day versus 15.8 MIU/day in DF patients. No differences were observed in any of the groups between the number of TILs reinfused and clinical response.

CONCLUSIONS

The study is still ongoing; it has been decided to focus on DF melanoma patients after radical metastasectomy, for whom the data seem to be encouraging. Further endpoints of the study are the role of IL-2 dosage in the adjuvant setting, and the possibility to make correlations between biological parameters and clinical results.

Harnessing the immune system in the battle against breast cancer

Breast cancer is the most prevalent malignancy in women and the second most common cause of cancer-related death worldwide. Despite major innovations in early detection and advanced therapeutics, up to 30% of women with node-negative breast cancer and 70% of women with node-positive breast cancer will develop recurrence. The recognition that breast tumors are infiltrated by a complex array of immune cells that influence their development, progression, and metastasis, as well as their responsiveness to systemic therapies has sparked major interest in the development of immunotherapies. In fact, not only the native host immune system can be altered to promote potent antitumor response, but also its components can be manipulated to generate effective therapeutic strategies. We present here a review of the major approaches to immunotherapy in breast cancers, both successes and failures, as well as new therapies on the horizon.

IL-2 and Beyond in Cancer Immunotherapy

The development of the T- and natural killer (NK) cell growth factor IL-2 has been a sentinel force ushering in the era of immunotherapy in cancer. With the advent of clinical grade recombinant IL-2 in the mid-1980s, oncologists could for the first time directly manipulate lymphocyte populations with systemic therapy. By itself, recombinant IL-2 can induce clinical responses in up to 15% of patients with metastatic cancer or renal cell carcinoma. When administered with adoptively transferred tumor-reactive lymphocytes, IL-2 promotes T cell engraftment and response rates of up to 50% in metastatic melanoma patients. Importantly, these IL-2-driven responses can yield complete and durable responses in a subset of patients. However, the use of IL-2 is limited by toxicity and concern of the expansion of T regulatory cells. To overcome these limitations and improve response rates, other T cell growth factors, including IL-15 and modified forms of IL-2, are in clinical development. Administering T cell growth factors in combination with other agents, such as immune checkpoint pathway inhibitors, may also improve efficacy. In this study, we review the development of T- and NK cell growth factors and highlight current combinatorial approaches based on these reagents.

Clinical Response Rates From Interleukin-2 Therapy for Metastatic Melanoma Over 30 Years' Experience: A Meta-Analysis of 3312 Patients

Interleukin-2 (IL-2), initially used in 1986, can induce clinical regression-complete responses (CR) and partial responses (PR) of metastatic malignant melanoma. IL-2 has been used alone or in combination, and in different dosage schedules, as an immunotherapeutic agent for melanoma treatment. This meta-analysis aimed to document and evaluate the spectrum of reported clinical response rates from the combined experience of almost 30 years of IL-2 clinical usage. Clinical trials using IL-2 for metastatic melanoma therapy that reported: dosage, combinations, study details, definitions and clinical CR, PR, and overall response (OR) rates were included. A meta-analysis was conducted using the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. In total, 34 studies met inclusion criteria, with 41 separate treatment arms. For all IL-2 treatment modalities collectively, the CR rate was 4.0% [95% confidence interval (CI), 2.8-5.3], PR 12.5% (95% CI, 10.1-15.0), and OR 19.7% (95% CI, 15.9-23.5). CR pre-1994 was 2.7% versus 6.1% post-1994. High and intermediate-IL-2 dosage showed no CR difference, while low-dose IL-2 showed a nonstatistical trend toward an increased CR rate. The highest CR rate resulted from IL-2 combined with vaccine at 5.0%. The meta-analysis showed that IL-2 immunotherapy for advanced metastatic melanoma delivered a CR rate of 4% (range, 0-23%) across nearly 30 years of clinical studies, with gradual improvement over time. The significance is that, contrary to popular belief, the data demonstrated that CR rates were similar for intermediate versus high-IL-2 dosing.

A First-in-Human Phase I Study of Subcutaneous Outpatient Recombinant Human IL15 (rhIL15) in Adults with Advanced Solid Tumors

Purpose: Preclinical data established IL15 as a homeostatic factor and powerful stimulator of NK and CD8⁺ T-cell function, the basis for clinical testing.Experimental Design: A first-in-human outpatient phase I dose escalation trial of subcutaneous (SC) rhIL15 was conducted in refractory solid tumor cancer patients. Therapy consisted of daily (Monday-Friday) subcutaneous injections of rhIL15 for two consecutive weeks (10 total doses/cycle). Clinical response was assessed by RECIST. Pharmacokinetics of rhIL15 and immune biomarkers were evaluated.Results: Nineteen patients were treated with rhIL15 at dose levels of 0.25, 0.5, 1, 2, and 3 mcg/kg/day. Fourteen patients completed ≥ 2 cycles of therapy that was well tolerated. One serious adverse event (SAE), grade 2 pancreatitis, required overnight hospitalization. Enrollment was halted after a patient receiving 3 mcg/kg/day developed a dose-limiting SAE of grade 3 cardiac chest pain associated with hypotension and increased troponin. No objective responses were observed; however, several patients had disease stabilization including a renal cell carcinoma patient who continued protocol treatment for 2 years. The treatment induced profound expansion of circulating NK cells, especially among the CD56^bright subset. A proportional but less dramatic increase was found among circulating CD8⁺ T cells with maximal 3-fold expansion for the 2 and 3 mcg/kg patients.Conclusions: SC rhIL15 treatment was well tolerated, producing substantial increases in circulating NK and CD8⁺ T cells. This protocol establishes a safe outpatient SC rhIL15 regimen of 2 mcg/kg/day dosing amenable to self-injection and with potential as a combination immunotherapeutic agent. Clin Cancer Res; 24(7); 1525-35. ©2017 AACR.

The progress and current status of immunotherapy in acute myeloid leukemia

Recently, there has been remarkable progress in basic and preclinical studies of acute myeloid leukemia (AML). The improved outcomes of AML can largely be attributed to advances in supportive care and hematopoietic cell transplantation as opposed to conventional chemotherapy. However, as the 5-year survival rate remains low due to a high incidence of relapse, novel and effective treatments are urgently needed. Increasing attention is focusing on identifying suitable immunotherapeutic strategies for AML. Here, we describe the immunological features, mechanisms of immune escape, and recent progress in immunotherapy for AML. Problems encountered in the clinic will also be discussed. Although current outcomes may be limited, ongoing preclinical or clinical efforts are aimed at improving immunotherapy modalities and designing novel therapies, such as vaccines, monoclonal antibody therapy, chimeric antibody receptor-engineered T cells (CAR-T), TCR-engineered T cells (TCR-T), and checkpoint inhibitors, which may provide promising and effective therapies with higher specificity and efficacy for AML.

Evolving Immunotherapy Approaches for Renal Cell Carcinoma

Metastatic renal cell carcinoma (mRCC) continues to be associated with high rates of morbidity and mortality. Renal cell carcinoma (RCC) is typically resistant to cytotoxic chemotherapy, and while targeted therapies have activity and prolong progression-free and overall survival, responses are usually not durable. Modulating the immune system with cytokine therapy, vaccine therapy, cell therapy, and checkpoint inhibitors offers hope of prolonged survival. Standard and emerging immune therapy approaches and combinations of immune therapies and other modalities are reviewed.

Novel immunotherapy in metastatic renal cell carcinoma

Despite the rapid development of therapeutic modalities for metastatic renal cell carcinoma (mRCC) over the past decade to include a number of targeted antiangiogenic therapies and traditional immunotherapy, such as high-dose interleukin-2 and interferon-α, mRCC continues to be associated with poor prognosis. Currently, several novel immunotherapy agents, such as cancer vaccines, adoptive cell therapy, and checkpoint inhibitors, such as programmed cell death-1 (PD-1 present on T cells), one of its ligands (PD-L1 present on antigen-presenting cells and tumor cells), and cytotoxic T-lymphocyte-associated protein-4 pathways, are being studied in mRCC and are showing promise as important steps in the management of this disease. This review summarizes the current landscape of standard and emerging immune therapeutics and other modalities for mRCC.

Immunotherapy for metastatic renal cell carcinoma

BACKGROUND

Since the mid-2000s, the field of metastatic renal cell carcinoma (mRCC) has experienced a paradigm shift from non-specific therapy with broad-acting cytokines to specific regimens, which directly target the cancer, the tumour microenvironment, or both.Current guidelines recommend targeted therapies with agents such as sunitinib, pazopanib or temsirolimus (for people with poor prognosis) as the standard of care for first-line treatment of people with mRCC and mention non-specific cytokines as an alternative option for selected patients.In November 2015, nivolumab, a checkpoint inhibitor directed against programmed death-1 (PD-1), was approved as the first specific immunotherapeutic agent as second-line therapy in previously treated mRCC patients.

OBJECTIVES

To assess the effects of immunotherapies either alone or in combination with standard targeted therapies for the treatment of metastatic renal cell carcinoma and their efficacy to maximize patient benefit.

SEARCH METHODS

We searched the Cochrane Library, MEDLINE (Ovid), Embase (Ovid), ISI Web of Science and registers of ongoing clinical trials in November 2016 without language restrictions. We scanned reference lists and contacted experts in the field to obtain further information.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) and quasi-RCTs with or without blinding involving people with mRCC.

DATA COLLECTION AND ANALYSIS

We collected and analyzed studies according to the published protocol. Summary statistics for the primary endpoints were risk ratios (RRs) and mean differences (MD) with their 95% confidence intervals (CIs). We rated the quality of evidence using GRADE methodology and summarized the quality and magnitude of relative and absolute effects for each primary outcome in our 'Summary of findings' tables.

MAIN RESULTS

We identified eight studies with 4732 eligible participants and an additional 13 ongoing studies. We categorized studies into comparisons, all against standard therapy accordingly as first-line (five comparisons) or second-line therapy (one comparison) for mRCC.Interferon (IFN)-α monotherapy probably increases one-year overall mortality compared to standard targeted therapies with temsirolimus or sunitinib (RR 1.30, 95% CI 1.13 to 1.51; 2 studies; 1166 participants; moderate-quality evidence), may lead to similar quality of life (QoL) (e.g. MD -5.58 points, 95% CI -7.25 to -3.91 for Functional Assessment of Cancer - General (FACT-G); 1 study; 730 participants; low-quality evidence) and may slightly increase the incidence of adverse events (AEs) grade 3 or greater (RR 1.17, 95% CI 1.03 to 1.32; 1 study; 408 participants; low-quality evidence).There is probably no difference between IFN-α plus temsirolimus and temsirolimus alone for one-year overall mortality (RR 1.13, 95% CI 0.95 to 1.34; 1 study; 419 participants; moderate-quality evidence), but the incidence of AEs of 3 or greater may be increased (RR 1.30, 95% CI 1.17 to 1.45; 1 study; 416 participants; low-quality evidence). There was no information on QoL.IFN-α alone may slightly increase one-year overall mortality compared to IFN-α plus bevacizumab (RR 1.17, 95% CI 1.00 to 1.36; 2 studies; 1381 participants; low-quality evidence). This effect is probably accompanied by a lower incidence of AEs of grade 3 or greater (RR 0.77, 95% CI 0.71 to 0.84; 2 studies; 1350 participants; moderate-quality evidence). QoL could not be evaluated due to insufficient data.Treatment with IFN-α plus bevacizumab or standard targeted therapy (sunitinib) may lead to similar one-year overall mortality (RR 0.37, 95% CI 0.13 to 1.08; 1 study; 83 participants; low-quality evidence) and AEs of grade 3 or greater (RR 1.18, 95% CI 0.85 to 1.62; 1 study; 82 participants; low-quality evidence). QoL could not be evaluated due to insufficient data.Treatment with vaccines (e.g. MVA-5T4 or IMA901) or standard therapy may lead to similar one-year overall mortality (RR 1.10, 95% CI 0.91 to 1.32; low-quality evidence) and AEs of grade 3 or greater (RR 1.16, 95% CI 0.97 to 1.39; 2 studies; 1065 participants; low-quality evidence). QoL could not be evaluated due to insufficient data.In previously treated patients, targeted immunotherapy (nivolumab) probably reduces one-year overall mortality compared to standard targeted therapy with everolimus (RR 0.70, 95% CI 0.56 to 0.87; 1 study; 821 participants; moderate-quality evidence), probably improves QoL (e.g. RR 1.51, 95% CI 1.28 to 1.78 for clinically relevant improvement of the FACT-Kidney Symptom Index Disease Related Symptoms (FKSI-DRS); 1 study, 704 participants; moderate-quality evidence) and probably reduces the incidence of AEs grade 3 or greater (RR 0.51, 95% CI 0.40 to 0.65; 1 study; 803 participants; moderate-quality evidence).

AUTHORS' CONCLUSIONS

Evidence of moderate quality demonstrates that IFN-α monotherapy increases mortality compared to standard targeted therapies alone, whereas there is no difference if IFN is combined with standard targeted therapies. Evidence of low quality demonstrates that QoL is worse with IFN alone and that severe AEs are increased with IFN alone or in combination. There is low-quality evidence that IFN-α alone increases mortality but moderate-quality evidence on decreased AEs compared to IFN-α plus bevacizumab. Low-quality evidence shows no difference for IFN-α plus bevacizumab compared to sunitinib with respect to mortality and severe AEs. Low-quality evidence demonstrates no difference of vaccine treatment compared to standard targeted therapies in mortality and AEs, whereas there is moderate-quality evidence that targeted immunotherapies reduce mortality and AEs and improve QoL.

The immune response in pregnancy and in cancer is active and supportive of placental and tumor cell growth not their destruction

While many investigators have described the biochemical and physiological similarities between tumor cells and trophoblast cells, in this discourse we will compare primarily their leucocytes, which constitute a large portion of the tumor and its microenvironment as well as the placenta and its microenvironment. There is a remarkable similarity between the cells that support placental growth and development and tumor growth and development. In many cases over half of the cells present in the tumor and the placenta are non-tumor or nontrophoblast cells, immune cells. Most of these immune cells are prevented from attacking the fetal derived placental cells and the self-derived tumor cells. Nevertheless, these leucocytes, in our opinion, are very active and support tumor and placental cell growth through the production of growth factors and angiogenic factors. These cells do this by activating the portion of the immune response which initiates and helps control tissue repair.

Immunotherapy in genitourinary malignancies

Treatment of cancer patients involves a multidisciplinary approach including surgery, radiotherapy, and chemotherapy. Traditionally, patients with metastatic disease are treated with combination chemotherapies or targeted agents. These cytotoxic agents have good response rates and achieve palliation; however, complete responses are rarely seen. The field of cancer immunology has made rapid advances in the past 20 years. Recently, a number of agents and vaccines, which modulate the immune system to allow it to detect and target cancer cells, are being developed. The benefit of these agents is twofold, it enhances the ability the body’s own immune system to fight cancer, thus has a lower incidence of side effects compared to conventional cytotoxic chemotherapy. Secondly, a small but substantial number of patients with metastatic disease are cured by immunotherapy or achieve durable responses lasting for a number of years. In this article, we review the FDA-approved immunotherapy agents in the field of genitourinary malignancies. We also summarize new immunotherapy agents being evaluated in clinical studies either as single agents or as a combination.

The use of immunotherapy in the treatment of melanoma

Patients with advanced melanoma have a compromised anti-tumor immune response leading to tumor immune tolerance and a tumor microenvironment conducive to disease progression. Immunotherapy that successfully overcomes this tumor-mediated immune suppression has made the greatest impact in the management of this disease over the past few years. This progress through immunotherapy builds upon earlier successes that interferon-α had in the treatment of melanoma in the adjuvant setting, as well as that of high-dose interleukin-2 in advanced melanoma. The development of immune checkpoint inhibitors has led to dramatic clinical activity in advanced melanoma. In particular, anti-CTLA4 and anti-PD1 monoclonal antibodies have taken us forward into the realm of longer survival and durable responses with the possibility of cure in a continuously increasing proportion of patients. Combination immunotherapeutic strategies and novel immunotherapeutic agents are being tested at an accelerated pace where the outlook for long-term survival benefits for the majority of patients appears brighter than ever.

Interleukin-2: Old and New Approaches to Enhance Immune-Therapeutic Efficacy

Interleukin-2 (IL-2) is a very well-known cytokine that has been studied for the past 35 years. It plays a major role in the growth and proliferation of many immune cells such NK and T cells. It is an important immunotherapy cytokine for the treatment of various diseases including cancer. Systemic delivery of IL-2 has shown clinical benefit in renal cell carcinoma and melanoma patients. However, its use has been limited by the numerous toxicities encountered with the systemic delivery. Intravenous IL-2 causes the well-known "capillary leak syndrome," or the leakage of fluid from the circulatory system to the interstitial space resulting in hypotension (low blood pressure), edema, and dyspnea that can lead to circulatory shock and eventually cardiopulmonary collapse and multiple organ failure. Due to the toxicities associated with systemic IL-2, an aerosolized delivery approach has been developed, which enables localized delivery and a higher local immune cell activation. Since proteins are absorbed via pulmonary lymphatics, after aerosol deposition in the lung, aerosol delivery provides a means to more specifically target IL-2 to the local immune system in the lungs with less systemic effects. Its benefits have extended to diseases other than cancer. Delivery of IL-2 via aerosol or as nebulized IL-2 liposomes has been previously shown to have less toxicity and higher efficacy against sarcoma lung metastases. Dogs with cancer provided a highly relevant means to determine biodistribution of aerosolized IL-2 and IL-2 liposomes. However, efficacy of single-agent IL-2 is limited. As in general, for most immune-therapies, its effect is more beneficial in the face of minimal residual disease. To overcome this limitation, combination therapies using aerosol IL-2 with adoptive transfer of T cells or NK cells have emerged.Using a human osteosarcoma (OS) mouse model, we have demonstrated the efficacy of single-agent aerosol IL-2 and combination therapy aerosol IL-2 and NK cells or aerosol IL-2 and interleukin 11 receptor alpha-directed chimeric antigen receptor-T cells (IL-11 receptor α CAR-T cells) against OS pulmonary metastases. Combination therapy resulted in a better therapeutic effect. A Phase-I trial of aerosol IL-2 was done in Europe and proved to be safe. Others and our preclinical studies provided the basis for the development of a Phase-I aerosol IL-2 trial in our institution to include younger patients with lung metastases. OS, our disease of interest, has a peak incidence in the adolescent and young adult years. Our goal is to complete this trial in the next 2 years.In this chapter, we summarize the different effects of IL-2 and cover the advantages of the aerosol delivery route for diseases of the lung with an emphasis on some of our most recent work using combination therapy aerosol IL-2 and NK cells for the treatment of OS lung metastases.

Tumor Infiltrating Mast Cells (TIMs) Confers a Marked Survival Advantage in Nonmetastatic Clear-Cell Renal Cell Carcinoma

PURPOSE

The role played by the innate immune system in determining the clinical outcome of clear-cell renal cell carcinoma (ccRCC) was still blurred. This study was designed to investigate the prognostic significance of tumor infiltrating mast cells (TIMs) in ccRCC.

METHODS

The study retrospectively enrolled a training set (474 patients) and a validation set (188 patients) with nonmetastasis (pT1-4N0M0) ccRCC from two institutional medical centers of China. TIMs was evaluated by immunohistochemical staining of tryptase and its association with clinicopathologic features and prognosis were evaluated.

RESULTS

In ccRCC tissues, TIMs ranged from 0 to 103 cells/mm² and 0 to 113 cells/mm² in the training set and validation set, respectively. TIMs was negatively correlated with tumor size (P < 0.001 and P < 0.001, respectively), pathological T stage (P = 0.005 and P = 0.007, respectively) and Fuhrman grade (P < 0.001 and P < 0.001, respectively). Patients with abundant TIMs infiltration showed significantly longer cancer-specific survival in the training cohort and the validation cohort (P < 0.001 and P < 0.001). Patients with abundant mast cell infiltration showed significantly longer overall survival in the TCGA cohort (P < 0.001). Moreover, multivariate analysis identified TIMs as an independent prognostic factor for cancer-specific survival (CSS) and relapse-free survival (RFS). Also, TIMs was significantly correlated with CSS and RFS of the mediate and high-risk patients in the training cohort and the validation cohort.

CONCLUSIONS

TIMs density is a powerful independent prognostic factor for CSS and RFS in patients with nonmetastasis (pT1-4N0M0) ccRCC.

Adoptive Cellular Therapy (ACT) for Cancer Treatment

Adoptive cellular therapy (ACT) with various lymphocytes or antigen-presenting cells is one stone in the pillar of cancer immunotherapy, which relies on the tumor-specific T cell. The transfusion of bulk T-cell population into patients is an effective treatment for regression of cancer. In this chapter, we summarize the development of various strategies in ACT for cancer immunotherapy and discuss some of the latest progress and obstacles in technical, safety, and even regulatory aspects to translate these technologies to the clinic. ACT is becoming a potentially powerful approach to cancer treatment. Further experiments and clinical trials are needed to optimize this strategy.

Targeting tumor tolerance: A new hope for pancreatic cancer therapy?

With a 5-year survival rate of just 8%, pancreatic cancer (PC) is projected to be the second leading cause of cancer deaths by 2030. Most PC patients are not eligible for surgery with curative intent upon diagnosis, emphasizing a need for more effective therapies. However, PC is notoriously resistant to chemoradiation regimens. As an alternative, immune modulating strategies have recently achieved success in melanoma, prompting their application to other solid tumors. For such therapeutic approaches to succeed, a state of immunologic tolerance must be reversed in the tumor microenvironment and that has been especially challenging in PC. Nonetheless, knowledge of the PC immune microenvironment has advanced considerably over the past decade, yielding new insights and perspectives to guide multimodal therapies. In this review, we catalog the historical groundwork and discuss the evolution of the cancer immunology field to its present state with a specific focus on PC. Strategies currently employing immune modulation in PC are reviewed, specifically highlighting 66 clinical trials across the United States and Europe.

Targeted Therapy of Hepatitis B Virus-Related Hepatocellular Carcinoma: Present and Future

Cancer immunotherapy using a patient’s own T cells redirected to recognize and kill tumor cells has achieved promising results in metastatic melanoma and leukemia. This technique involves harnessing a patient’s T cells and then delivering a gene that encodes a new T cell receptor (TCR) or a chimeric antigen receptor (CAR) that allow the cells to recognize specific cancer antigens. The prospect of using engineered T cell therapy for persistent viral infections like hepatitis B virus (HBV) and their associated malignancies is promising. We recently tested in a first-in-man clinical trial, the ability of HBV-specific TCR-redirected T cells to target HBsAg-productive hepatocellular carcinoma (HCC) and demonstrated that these redirected T cells recognized HCC cells with HBV–DNA integration [1] We discuss here the possibility to use HBV-specific TCR-redirected T cells targeting hepatitis B viral antigens as a tumor specific antigen in patients with HBV-related HCC, and the potential challenges facing the development of this new immunotherapeutic strategy.

Redirecting T Cell Specificity Using T Cell Receptor Messenger RNA Electroporation

Autologous T lymphocytes genetically modified to express T cell receptors or chimeric antigen receptors have shown great promise in the treatment of several cancers, including melanoma and leukemia. In addition to tumor-associated antigens and tumor-specific neoantigens, tumors expressing viral peptides can also be recognized by specific T cells and are attractive targets for cell therapy. Hepatocellular carcinoma cells often have hepatitis B virus DNA integration and can be targeted by hepatitis B virus-specific T cells. Here, we describe a method to engineer hepatitis B virus-specific T cell receptors in primary human T lymphocytes based on electroporation of hepatitis B virus T cell receptor messenger RNA. This method can be extended to a large scale therapeutic T cell production following current good manufacturing practice compliance and is applicable to the redirection of T lymphocytes with T cell receptors of other virus specificities such as Epstein-Barr virus, cytomegalovirus, and chimeric receptors specific for other antigens expressed on cancer cells.

WITHDRAWN: Immunotherapy for advanced renal cell cancer

This review is being updated and replaced following the publication of a new protocol (Unverzagt S, Moldenhauer I, Coppin C, Greco F, Seliger B. Immunotherapy for metastatic renal cell carcinoma [Protocol]. Cochrane Database of Systematic Reviews 2015, Issue 4. Art. No.: CD011673. DOI: 10.1002/14651858.CD011673). It will remain withdrawn when the new review is published.

The editorial group responsible for this previously published document have withdrawn it from publication.

2015 Guidance on cancer immunotherapy development in early-phase clinical studies

The development of cancer immunotherapies is progressing rapidly with a variety of technological approaches. They consist of "cancer vaccines", which are based on the idea of vaccination, "effector cell therapy", classified as passive immunotherapy, and "inhibition of immunosuppression", which intends to break immunological tolerance to autoantigens or immunosuppressive environments characterizing antitumor immune responses. Recent reports showing clinical evidence of efficacy of immune checkpoint inhibitors and adoptive immunotherapies with tumor-infiltrating lymphocytes and tumor-specific receptor gene-modified T cells indicate the beginning of a new era for cancer immunotherapy. This guidance summarizes ideas that will be helpful to those who plan to develop cancer immunotherapy. The aims of this guidance are to discuss and offer important points in early phase clinical studies of innovative cancer immunotherapy, with future progress in this field, and to contribute to the effective development of cancer immunotherapy aligned with the scope of regulatory science. This guidance covers cancer vaccines, effector cell therapy, and inhibition of immunosuppression, including immune checkpoint inhibitors.

Effector Functions of Natural Killer Cell Subsets in the Control of Hematological Malignancies

Treatment of hematological malignant disorders has been improved over the last years, but high relapse rate mainly attributable to the presence of minimal residual disease still persists. Therefore, it is of great interest to explore novel therapeutic strategies to obtain long-term remission. Immune effector cells, and especially natural killer (NK) cells, play a crucial role in the control of hematological malignancies. In this regard, the efficiency of allogeneic stem cell transplantation clearly depends on the immune-mediated graft versus leukemia effect without the risk of inducing graft versus host disease. Alloreactive donor NK cells generated following hematopoietic stem cell transplantation ameliorate the outcome of leukemia patients; in addition, in vivo transfer of in vitro expanded NK cells represents a crucial tool for leukemia treatment. To improve NK cell effector functions against resistant leukemia cells, novel immunotherapeutic strategies are oriented to the identification, isolation, expansion, and administration of particular NK cell subsets endowed with multifunctional anti-tumor potential and tropism toward tumor sites. Moreover, the relationship between the emergence and persistence of distinct NK cell subsets during post-graft reconstitution and the maintenance of a remission state is still rather unclear.

Evaluation of the prognostic impact of postoperative adjuvant radiotherapy on head and neck mucosal melanoma: a meta-analysis

Background

Head and neck mucosal melanoma (HNMM) is a rare type of malignant tumor that frequently exhibits postoperative recurrence and distant metastasis. Many clinicians administer postoperative adjuvant radiotherapy to improve patient prognosis and enhance quality of life; however, the effects of this treatment remain controversial. Therefore, in this study, a meta-analysis was performed to evaluate the practical value of postoperative adjuvant radiotherapy for head and neck mucosal melanoma.

Methods

Articles in the PubMed, MEDLINE, Cochrane Library, Web of Science and EMBASE databases were systematically retrieved. Analyses were conducted to compare the impact of treatments involving postoperative radiotherapy with treatments entailing surgery alone on patient overall survival time, local recurrence and distant metastasis. The hazard ratio (HR) was used to evaluate the time-to-event data employing RevMan version 5.2 and Stata/SE version 13.0 software according to the principles specified for systematic reviews of interventions in the Cochrane handbook.

Results

Twelve cohort studies involving 1593 patients satisfied the desired conditions. In comparing surgery alone with postoperative radiotherapy, there was no significant difference regarding a decrease in the death risk in HNMM patients (HR, 1.07; 95 % CI, 0.95–1.2; p = 0.903; low heterogeneity, I² = 0); this was also the case for sinonasal melanoma after subgroup meta-analysis (HR, 1.04; 95 % CI, 0.8–1.36; p = 0.983; low heterogeneity, I² = 0 %). A sensitivity analysis and subgroup meta-analysis showed that disease progression was the main source of the instability in the results. Surgery combined with postoperative radiotherapy reduced the risk of local recurrence (HR, 0.51; 95 % CI, 0.35–0.76; p = 0.155) but did not reduce the risk of distant metastasis (HR, 2.26; 95 % CI, 1.01–5.05; p = 0.006).

Conclusions

This study demonstrated that for HNMM patients surgery is recommended if indicated, and surgery combined with postoperative radiotherapy is also recommended for dramatically improved local control of the tumor bed. For patients not suitable for surgical treatment, radiotherapy is still advised. To control distant metastasis and finally lower the risk of death, immunological therapy is another potential option whose therapeutic effect needs to be proved with more data from clinical trials.

Anti-PD-1 and PD-L1 therapy for bladder cancer: what is on the horizon?

Oncologic therapeutics has evolved enormously as we entered the 21st century. Unfortunately, the treatment of advanced urothelial cancer has remained unchanged over the last two decades despite a better understanding of the genetic alterations in bladder cancer. Pathways such as the PI3K/AKT3/mTOR and FGFR have been implicated in urothelial bladder cancer. However, targeted therapies have not shown proven benefit yet and are still considered investigational. Recently, researchers have been successful in manipulating the systemic immune response to mount antitumor effects in melanoma, lung cancer and lymphoma. Historically, intravesical Bacillus Calmette–Guérin immunotherapy has been highly active in nonmuscle invasive bladder cancer. Early data suggest that immune checkpoint inhibitors will soon prove to be another cornerstone in the treatment armamentarium of advanced bladder cancer.

Harnessing the PD-1 pathway in renal cell carcinoma: current evidence and future directions

Programmed cell death-1 (PD-1) is a recognized immune checkpoint. It is frequently upregulated on the T cells that infiltrate tumors, providing an inhibitory signal, which may facilitate immune escape. Blocking antibodies have been developed to interrupt the interaction of PD-1 with its ligands PD-L1/PD-L2, with the goal of increasing the host antitumor immune response. Initial results have been encouraging, with durable responses in both treatment-naive and pretreated patients, along with an acceptable toxicity profile. This tolerability makes PD-1 blockade an excellent potential partner for combination strategies with the approved targeted agents, such as tyrosine kinase inhibitors (TKIs) and anti-vascular endothelial growth factor (anti-VEGF) antibodies, as well as other investigational immune checkpoint inhibitors or agonist antibodies that may costimulate an immune response. PD-L1 expression on tumor cells and tumor-infiltrating immune cells is also being evaluated as a predictive biomarker of response to treatment. This review summarizes the biological basis, preclinical studies, ongoing trials, and future challenges associated with targeting the PD-1 pathway in renal cell carcinoma.

Immunotherapy of melanoma

Melanoma is considered one of the immunogenic - if not the most immunogenic - malignancies. This is based on several observations.1.Spontaneous remissions occur occasionally.2.In about 5% of melanomas no primary tumour is found. The genetic aberrations of these tumours closely resemble those of cutaneous melanomas, and therefore are suggestive of spontaneous regressions of the primary tumours.3.Both primary tumours and metastases often have brisk lymphocytic infiltrates, a phenomenon that is correlated with better outcome.4.Studies of isolates of these tumour-infiltrating T lymphocytes have revealed that a proportion of these cells recognise melanoma antigens.5.Melanomas respond to immunotherapy. These observations have led to over 30 years of research on immunotherapy for melanoma; many of these efforts have failed, with only a few exceptions: interleukin-2 (IL-2) and to a lesser degree interferon-a (IFN-〈). Recently, new developments in immunotherapy have revolutionised this treatment modality. Anti-CTLA4 has received approval from the Food and Drugs Administration (FDA) and the European Medicines Agency (EMA) for the treatment of stage IV melanomas based on the improvement in overall survival in phase III trials, and more recently blockade of PD1/PDL1 interactions has shown objective clinical responses in a stage IV melanoma in early-phase clinical trials. In addition, several independent single-institution phase I/II trials using adoptive cell therapy have shown a consistently high response rate, including durable complete remissions in a substantial percentage of treated patients. Now, for the first time, immunotherapy has moved beyond the treatment of melanoma as both CTLA4 and PD1 blockade have been shown to induce objective responses in other tumour types as well. This chapter will discuss the mechanism of action, clinical efficacy and side effects of IL-2, the novel treatments consisting of the immune checkpoint blockade drugs anti-CTLA4 and anti-PD1 and adoptive cell therapy.

Adoptive immunotherapy of cancer utilizing genetically engineered lymphocytes

It is becoming increasingly clear that adoptive immunotherapy with genetically engineered T cells has the potential to control and even cure cancer in some patients. On the other hand, severe adverse events associated with efficacy have frequently been reported in clinical trials. Current and near-future challenges for the development of adoptive immunotherapy of cancer using genetically engineered T cells include minimization and prediction of adverse events; identification of new and effective targets, including patient-specific mutations; improvement in T cell functionality, persistence, and memory formation capacity; and utilization of allogeneic or cell line-based T cells.

Anticancer Cytokines: Biology and Clinical Effects of Interferon-α2, Interleukin (IL)-2, IL-15, IL-21, and IL-12

Efforts over nearly four decades have focused on ways to use cytokines to manipulate the host immune response towards cancer cell recognition and eradication. Significant advances were achieved with interleukin-2 (IL-2) and interferon-α (IFN-α), primarily in the treatment of patients with melanoma and renal cell carcinoma. However, the utility of other cytokines showing promise in the preclinical setting has not been established largely because of toxicity, the complex functionality of each cytokine and the difficulty mimicking in preclinical models the human environment. Here, we review the basic biology and the clinical experiences with IFN-α, IL-2, IL-15, IL-21, and IL-12. We will also review ongoing clinical trials and discuss future directions including potential use of cytokines in combination with other effective immunotherapy approaches that have come of age in recent years.

Revving up Natural Killer Cells and Cytokine-Induced Killer Cells Against Hematological Malignancies

Natural killer (NK) cells belong to innate immunity and exhibit cytolytic activity against infectious pathogens and tumor cells. NK-cell function is finely tuned by receptors that transduce inhibitory or activating signals, such as killer immunoglobulin-like receptors, NK Group 2 member D (NKG2D), NKG2A/CD94, NKp46, and others, and recognize both foreign and self-antigens expressed by NK-susceptible targets. Recent insights into NK-cell developmental intermediates have translated into a more accurate definition of culture conditions for the in vitro generation and propagation of human NK cells. In this respect, interleukin (IL)-15 and IL-21 are instrumental in driving NK-cell differentiation and maturation, and hold great promise for the design of optimal NK-cell culture protocols. Cytokine-induced killer (CIK) cells possess phenotypic and functional hallmarks of both T cells and NK cells. Similar to T cells, they express CD3 and are expandable in culture, while not requiring functional priming for in vivo activity, like NK cells. CIK cells may offer some advantages over other cell therapy products, including ease of in vitro propagation and no need for exogenous administration of IL-2 for in vivo priming. NK cells and CIK cells can be expanded using a variety of clinical-grade approaches, before their infusion into patients with cancer. Herein, we discuss GMP-compliant strategies to isolate and expand human NK and CIK cells for immunotherapy purposes, focusing on clinical trials of adoptive transfer to patients with hematological malignancies.

Blinded by the light: why the treatment of metastatic melanoma has created a new paradigm for the management of cancer

Until recently, treatment for metastatic melanoma was characterised by a limited availability of treatment options that offer objective survival benefit. Cytotoxic agents fundamentally lack the ability to achieve disease control and cytokine therapy with interleukin-2 has an unacceptably high - for the use across all patient cohorts - rate of toxicities. The validation of braf as an oncogene driving melanoma tumorigenesis, as well as the discovery of the role of CTLA-4 receptor in the evasion of anticancer immune response by melanoma, has revolutionised our treatment options against a disease with dismal prognosis. Quick implementation of translational discoveries brought about BRAF/MEK inhibition in clinic, while at the same time, wider experience with CTLA-4 blockade enabled clinicians to manage previously fatal immune-related toxicities with greater confidence. The suitability for clinical use of other oncogenic drivers such as NRAS and c-kit is currently being tested whilst the PD-1/PD-L1/PD-L2 axis has emerged as a new immunotherapy target with exciting early phase results. The recent exponential progress in treatment of melanoma has set an example of translational medicine and the current review aims to explain why, as well as suggesting new goals for the future.

PD-1 blockade therapy in renal cell carcinoma: current studies and future promises

RCC is considered an immunogenic tumor with a prominent dysfunctional immune cell infiltrate, unable to control tumor growth. Evasion of immune surveillance, a process defined immune-editing, leads to malignant progression. The striking improvement of knowledge in immunology has led to the identification of immune checkpoints (such as CTLA-4 and PD-1), whose blockage enhances the antitumor immunity. The interaction between PD-1, an inducible inhibitory receptor expressed on lymphocytes and DCs, and PD-L1 ligand, expressed by tumor cells, results in a down-regulation of the T-cell response. Therefore, the PD-1/PD-L1 axis inhibition by targeted-antibodies, increasing the T-cell proliferation and cytotoxicity, represents a promising mechanism to stimulate the anti-tumor activity of the immune system, improving the outcomes of cancer patients. Several PD-1 and PD-L1 inhibitors have been evaluated in different tumor types, showing promising results. The interesting correlation between lymphocytes PD-1 expression and RCC advanced stage, grade and prognosis, as well as the selective PD-L1 expression by RCC tumor cells and its potential association with worse clinical outcomes, have led to the development of new anti PD-1/PD-L1 agents, alone or in combination with anti-angiogenic drugs or other immunotherapeutic approaches, for the treatment of RCC. In this review we discuss the role of PD-1/PD-L1 in RCC, focusing on the biological rationale, current clinical studies and promising therapeutic perspectives to target the PD-1 pathway.

Adoptive cell transfer for patients with metastatic melanoma: the potential and promise of cancer immunotherapy

BACKGROUND

Current FDA-approved therapeutic options for patients with metastatic melanoma include dacarbazine, interleukin 2, ipilimumab, vemurafenib, dabrafenib, and trametinib, but long-term tumor regression using available agents remains out of reach for most patients. Adoptive cell transfer (ACT) with autologous tumor-infiltrating lymphocytes (TILs) has shown encouraging results in clinical trials, with evidence of durable ongoing complete responses in patients with advanced melanoma. Emerging techniques to engineer T-cell receptors (TCRs) or chimeric antigen receptors (CARs) using lymphocytes from peripheral blood may offer new tactics in ACT.

METHODS

We reviewed the literature to provide a synopsis on the development and clinical trial results of ACT, as well as the future outlook for using ACT in patients with metastatic melanoma.

RESULTS

ACT with TILs as part of a lymphodepleting regimen has been shown in clinical trials to cause objective clinical responses in approximately 40% to 72% of patients with metastatic melanoma, with up to 40% of those patients experiencing complete responses lasting up to 7 years ongoing. Pilot trials using TCR-engineered cells against melanoma-associated antigens MART-1 and gp100 and the cancer-testis antigen NY-ESO-1 have shown clinical responses in patients with melanoma. CAR cells directed against melanoma have been tested only in preclinical models; however, CAR cells targeting other histologies such as lymphoma have elicited antitumor responses in patients.

CONCLUSIONS

An example of state-of-the-art personalized medicine, ACT is a potentially curative therapy for patients with metastatic melanoma. Ongoing trials aiming to simplify the regimens may allow a broader range of patients to be treated and enable ACT to be offered by academic cancer centers.

IL-2: the first effective immunotherapy for human cancer

The ability of IL-2 to expand T cells with maintenance of functional activity has been translated into the first reproducible effective human cancer immunotherapies. The administration of IL-2 can lead to durable, complete, and apparently curative regressions in patients with metastatic melanoma and renal cancer. The growth of large numbers of tumor-infiltrating lymphocytes with in vitro anti-cancer activity in IL-2 has led to the development of cell transfer therapies that are highly effective in patients with melanoma. The genetic modification of T cells with genes encoding αβ TCRs or chimeric Ag receptors and the administration of these cells after expansion in IL-2 have extended effective cell transfer therapy to other cancer types.

Apoptosis induced by 2-aryl benzothiazoles-mediated photodynamic therapy in melanomas via mitochondrial dysfunction

A mild and efficient synthetic development of 2-arylbenzothiazoles 5 mediated by ceric ammonium nitrate (CAN) via intramolecular cyclization of N-phenyl-thiobenzamides 4 was achieved. Further compounds 5 were reduced to corresponding amines 6, and their photodynamic therapy (PDT) effect was evaluated on malignant human melanoma A375 cells. Amine 6l plus ultraviolet A (UVA) induced caspase-3 activity, poly(ADP-ribose)polymerase cleavage, M30 positive CytoDeath staining, and subsequent apoptotic cell death. Our data disclosed that treatment of A375 cells with 6l plus UVA resulted in a decrease in mitochondrial membrane potential (ΔΨmt), oxidative phosphorylation system (OXPHOS) subunits, and adenosine triphosphate (ATP) but an increase in mitochondrial DNA 4977-bp deletion via reactive oxygen species (ROS) generation. Transmission electron microscopy (TEM) observations also showed major ultrastructural alterations of mitochondria. Additionally, 6l plus UVA was also shown to reduce murine melanoma size in a mouse model. The present study supports the hypothesis that 6l-PDT may serve as a potential ancillary modality for the treatment of melanoma.

Clinical application of adoptive T cell therapy in solid tumors

As an emerging therapeutic approach, adoptive T cell therapy shown promise in advanced solid malignancies. The results obtained in patients with metastatic melanoma and kidney cancer are encouraging because of the visible clinical benefits and limited adverse effects. Recently, the genetically-modified T cells expressing specific T cell receptors or chimeric antigen receptors are just now entering the clinical arena and show great potential for high avidity to tumor-associated antigens and long-lasting anti-tumor responses. However, continued investigations are necessary to improve the cell product quality so as to decrease adverse effects and clinical costs, and make adoptive T cell therapy a tool of choice for solid malignancies.