A review of recent findings involving interleukin-2-based cancer therapy

Nanomaterials with changeable physicochemical property for boosting cancer immunotherapy

The past decade has witnessed a great progress in cancer immunotherapy with the sequential approvals of therapeutic cancer vaccine, immune checkpoint inhibitor and chimeric antigen receptor (CAR) T cell therapy. However, some hurdles still remain to the wide implementation of cancer immunotherapy, including low immune response, complex tumor heterogeneity, off-target immunotoxicity, poor solid tumor infiltration, and immune evasion-induced treatment tolerance. Owing to changeable physicochemical properties in response to endogenous or exogenous stimuli, nanomaterials hold the remarkable potential in incorporation of multiple agents, efficient biological barrier penetration, precise immunomodulator delivery, and controllable content release for boosting cancer immunotherapy. Herein, we review the recent advances in nanomaterials with changeable physicochemical property (NCPP) to develop cancer vaccine, remold tumor microenvironment and evoke direct T cell activation. Besides, we provide our outlook on this emerging field at the intersection of NCPP design and cancer immunotherapy.

Utilization and impact of immunotherapy in stage IV melanoma using the National Cancer Database

To evaluate factors affecting the utilization of immunotherapy and to stratify results based on the approval of ipilimumab in 2011 and PD-1 inhibitors in 2014, an analysis of available data from the National Cancer Database (NCDB) was performed. Stage IV melanoma patients were identified. Effects of immunotherapy on overall survival (OS) were assessed using Kaplan-Meier curves and Cox proportional hazards model. A total of 19 233 patients were analyzed and 1998 received immunotherapy. Between 2011 and 2013, and in 2014, 18.6 and 28.9% of patients received immunotherapy, respectively. Patients who received immunotherapy from 2011 to 2013 had a 33% (95% CI, 30-35%) 3-year OS compared to 23% (95% CI, 21-24%). In 2014, 3-year OS was 37% (95% CI, 32-43%) for those who received immunotherapy compared to 22% (95% CI, 18-26%) for those who did not (P < 0.0001). This is the first analysis of a large cancer database for melanoma patients with stratification based on utilization and availability of immunotherapy. Immunotherapy increased yearly and improved OS. With combination immunotherapy now more widely employed, it is expected these results will continue to improve. This is the first analysis of a large cancer database for melanoma patients with stratification based on utilization and availability of immunotherapy demonstrating that immunotherapy increased yearly and improved OS.

In-transit metastatic cutaneous melanoma: current management and future directions

Management of in-transit melanoma encompasses a variety of possible treatment pathways and modalities. Depending on the location of disease, number of lesions, burden of disease and patient preference and characteristics, some treatments may be more beneficial than others. After full body radiographic staging is performed to rule out metastatic disease, curative therapy may be performed through surgical excision, intraarterial regional perfusion and infusion therapies, intralesional injections, systemic therapies or various combinations of any of these. While wide excision is limited in indication to superficial lesions that are few in number, the other listed therapies may be effective in treating unresectable disease. Where intraarterial perfusion based therapies have been shown to successfully treat extremity disease, injectable therapies can be used in lesions of the head and neck. Although systemic therapies for in-transit melanoma have limited specific data to support their primary use for in-transit disease, there are patients who may not be eligible for any of the other options, and current clinical trials are exploring the use of concurrent and sequential use of regional and systemic therapies with early results suggesting a synergistic benefit for oncologic response and outcomes.

Durability of Complete Response to Intralesional Interleukin-2 for In-Transit Melanoma

Background

Intralesional injection of interleukin-2 (IL-2) for in-transit melanoma (ITM) is associated with a high rate of complete response. However, there is a paucity of data on treatment durability and long-term outcomes.

Objectives

To provide long-term data on patients with a complete response to IL-2 therapy for ITM.

Methods

Consecutive patients with ITM, treated with intralesional IL-2 therapy, at the Tom Baker Cancer Center were identified from April 2009 to August 2019. All patients received at least 4 cycles (every 2 weeks) of IL-2 (5 MIU/mL). Complete response was defined as sustained (ie, 3 months) clinical complete remission of all known in-transit disease.

Results

Sixty-five patients were treated with curative intent for in-transit disease with intralesional IL-2. Complete clinical response was identified in 44.6% (29/65). In this subset of patients, the median number of lesions per patient was 9 (range 1-40). The median total dose of IL-2 was 0.8 mL (IQR 0.4-1.5) per lesion. One patient received isolated limb infusion and 13.8% (4/29) received systemic immunotherapy as part of their initial management. At a median follow-up of 27 months (IQR 16-59), 34.5% (10/29) developed recurrent disease. Of these patients, 50.0% (5/10) presented with synchronous in-transit and distant metastases. The median time to recurrence was 10.5 months (IQR 5.8-16.3).

Conclusion

With long-term follow-up, 65.5% of complete responders have a durable response to intralesional IL-2 therapy. In this cohort of patients, local in-transit recurrence is most likely to occur within 12 months and is often associated with concomitant distant disease.

Nanomaterials for T-cell cancer immunotherapy

T-cell-based immunotherapies hold promise for the treatment of many types of cancer, with three approved products for B-cell malignancies and a large pipeline of treatments in clinical trials. However, there are several challenges to their broad implementation. These include insufficient expansion of adoptively transferred T cells, inefficient trafficking of T cells into solid tumours, decreased T-cell activity due to a hostile tumour microenvironment and the loss of target antigen expression. Together, these factors restrict the number of therapeutically active T cells engaging with tumours. Nanomaterials are uniquely suited to overcome these challenges, as they can be rationally designed to enhance T-cell expansion, navigate complex physical barriers and modulate tumour microenvironments. Here, we present an overview of nanomaterials that have been used to overcome clinical barriers to T-cell-based immunotherapies and provide our outlook of this emerging field at the interface of cancer immunotherapy and nanomaterial design.

Adverse childhood experiences (ACEs), cell-mediated immunity, and survival in the context of cancer

PURPOSE

Adverse childhood experiences (ACEs) have been shown to be associated with increased risk of mortality. The biobehavioral mechanisms linking adverse events and survival in cancer patients remain unclear. The aims of the study were to: (1) examine the rates and types of early adverse events in patients diagnosed with cancer; (2) investigate the association of adverse events with circulating cytokines, representing immune status of the patient; and (3) test whether immune markers mediated the association between early adverse events and survival while adjusting for other factors that are associated with immunity (e.g., fatigue) and survival (e.g., depression).

PATIENTS AND METHODS

The patients were recruited from an outpatient oncology clinic. Patients were administered a battery of questionnaires including the Traumatic Events Survey and the Center for Epidemiological Studies-Depression scale. Blood was collected and serum levels of cytokines were assessed to characterize immune status. Descriptive statistics, Mann-Whitney U tests and Cox regression were performed to address study aims.

RESULTS

Of the 408 patients, 66% reported at least one ACE. After adjusting for demographic, disease-specific factors, and psychological/behavioral factors; having had a major upheaval between parents during childhood or adolescence was associated with poorer survival [β = -0.702, HR = 0.496, p = 0.034]. Lower levels of interleukin-2 (IL-2) explained, in part, the link between this early adverse event and poorer survival as when IL-2 was entered into the model, a major upheaval between one's parents and survival was no longer significant [β = -0.612, HR = 0.542, p = 0.104].

CONCLUSION

Having experienced an ACE was associated with lower IL-2 levels-a growth factor for anti-inflammatory T-regulatory lymphocytes-central in contemporary immunotherapy, as well as poorer survival in those diagnosed with cancer. Since lower IL-2 levels also explained, in part, the link between the ACE involving parental upheaval and survival, there is support for a psychoneuroimmunological model of disease course in this vulnerable population.

Neo-DREAM study investigating Daromun for the treatment of clinical stage IIIB/C melanoma

High-risk resectable melanoma poses therapeutic challenges as this subgroup remains most vulnerable for disease recurrence. Immunotherapy has established its efficacy in cases of advanced melanoma, and now is actively being investigated in the multimodal management of resectable disease. Daromun, an intralesional immunocytokine, has emerged as a unique immunotherapy in its ability to preferentially target tumor cells, resulting in direct destruction, while generating a bystander effect that leads to a distant treatment effect. On the basis of its mechanism of action, there is growing interest in delivering immune-based therapies in a neoadjuvant setting. In this review, the neo-DREAM study, a Phase III trial comparing the safety and efficacy of neoadjuvant Daromun for resectable stage IIIB/C melanoma will be described. Clinical Trial Registration Number: NCT03567889.

Management of Locoregionally Advanced Melanoma

Melanoma has a unique propensity for locoregional metastasis secondary to intralymphatic transit not seen in other cutaneous or soft tissue malignancies. Novel intralesional therapies using oncolytic immunotherapy exhibit increasing response rates with observed bystander effect. Intralesional modalities in combination with systemic immunotherapy are the subject of ongoing clinical trials. Regional therapy is used in isolated limb locoregional metastasis whereby chemotherapy is delivered to an isolated limb avoiding systemic side effects. Multimodal treatment strategy is imperative in the treatment of locoregionally advanced melanoma. One must be versed on these quickly evolving therapeutic options.

Lectin isolated from Bothrops jararacussu venom induces IL-10 release by TCD4+ cells and TNF-α release by monocytes and natural killer cells

BjcuL is a C-type lectin isolated from Bothrops jararacussu snake venom with specificity for binding β-d-galactose units. BjcuL is not toxic to human peripheral blood mononuclear cells (PBMCs), but it inhibits PBMC proliferation and stimulates these cells to produce superoxide anions and hydrogen peroxide primarily via lymphocyte stimulation; it does not stimulate the production of nitric oxide and PGE₂ . The purpose of this study was to investigate the effect of BjcuL on PBMC activation with a focus on cytokine release modulating PBMC proliferation. The results showed for the first time that BjcuL coupled to FITC interacted with monocytes, B cells, natural killer (NK) cells, and with subpopulations of T cells. These cell-cell interactions can lead to cell activation and inflammatory cytokines release, such as IL-6 and TNF-α, as well as the anti-inflammatory cytokine IL-10. In addition, TNF-α release was attributed to NK cells and monocytes, whereas IL-10 was attributed to TCD4⁺ and Treg cells when stimulated by BjcuL. The temporal cytokines profile produced by cells when stimulated with this lectin allows us to assert that BjcuL has immunomodulatory activity in this context.

Immunotherapy and targeted therapies in older patients with advanced melanoma; Young International Society of Geriatric Oncology review paper

Malignant melanoma is an aggressive cancer associated with a poor prognosis in patients with metastatic disease. As in many other cancers, the incidence of melanoma rises with age; and combined with the longer life expectancy, this led to an increasing prevalence of melanoma in the older population. Recently, immune checkpoint inhibitors significantly improved the treatment of melanoma given their efficacy and tolerability profile. Two major classes of agents include the anti-cytotoxic T lymphocyte-associated protein 4 (CTLA-4) inhibitors, such as ipilimumab, and the anti-programmed death-ligand 1 (PD-1) inhibitors, such as nivolumab and pembrolizumab. Treatment of metastatic disease with immune checkpoint inhibitors demonstrated improved efficacy and better safety profiles compared to cytotoxic drugs and appears to be an attractive treatment option. Nevertheless, there is a need for tools designed to better predict which older patients will benefit from its use and who will experience toxicities related to the treatment. Current data do not show a major increase in toxicity rates in older patients. However, patients above 75 are often under-represented and those who are included are not representative of the general population of older patients, thereby also stressing the need for real-life data. Ongoing research is aiming at maximizing the potential treatment efficacy and developing novel immune-targeting modalities. Future studies should include older patients and assess geriatric domains in these older patients to better guide decision-making. This review discusses published clinical trials and where known, the efficacy and toxicity in older patients. Moreover, the clinical implications and future perspectives are discussed, with current recommendations for older patients, management of toxicities, and a proposal for an initial approach to the treatment of older patients with metastatic melanoma.

Prospective Analyses of Cytokine Mediation of Sleep and Survival in the Context of Advanced Cancer

OBJECTIVE

The aims of this study were to examine the potential association between sleep problems, symptom burden, and survival in patients with advanced cancer.

METHODS

A prospective study of 294 patients with gastrointestinal cancer administered questionnaires assessing sleep, depression, anxiety, stress, pain, fatigue, and health-related quality of life. Serum levels of cytokines including interleukin (IL)-1α, IL-1β, tumor necrosis factor α, IL-10, IL-2, and interferon-γ were measured to assess biological mediation between sleep and survival. Survival was measured as time from diagnosis to death.

RESULTS

Fifty-nine percent of patients reported poor sleep quality, 53% reported poor sleep efficiency, 39% reported sleep latency greater than 30 minutes, and 45% reported sleeping less than 6 hours or greater than 10 hours. We found a significant association between sleep duration and symptom burden. Shorter sleep duration was significantly associated with higher levels of fatigue (r = -0.169, p = .01), pain (r = -0.302, p = .01), anxiety (r = -0.182, p = .01), depression (r = -0.172, p = .003), and lower levels of quality of life (r = 0.240, p = .01). After adjustment for demographic, psychological, and disease-specific factors, short sleep duration was associated with reduced survival (hazard ratio [HR] linear = 0.485, 95% confidence interval = 0.275-0.857) and there was also evidence for a quadratic pattern (HR quadrati = 1.064, 95% confidence interval = 1.015-1.115) suggesting a curvilinear relationship between sleep duration and survival. Interleukin 2 was the only cytokine significantly related to survival (HR = 1.01, p = .003) and sleep duration (β = -30.11, p = .027). When of IL-2 was added to the multivariable model, short and long sleep (β = -0.557, p = .097; β = 0.046, p = .114) were no longer significantly related to survival, suggesting mediation by IL-2.

CONCLUSION

Sleep duration was associated with symptom burden and poorer survival and IL-2 was found to mediate the association between sleep and survival. Screening and treatment of sleep problems in patients diagnosed with cancer are warranted.

Tune Up In Situ Autovaccination against Solid Tumors with Oncolytic Viruses

With the progress of immunotherapy in cancer, oncolytic viruses (OVs) have attracted more and more attention during the past decade. Due to their cancer-selective and immunogenic properties, OVs are considered ideal candidates to be combined with immunotherapy to increase both specificity and efficacy in cancer treatment. OVs preferentially replicate in and lyse cancer cells, resulting in in situ autovaccination leading to adaptive anti-virus and anti-tumor immunity. The main challenge in OV approaches is how to redirect the host immunity from anti-virus to anti-tumor and optimize the clinical outcome of cancer patients. Here, we summarize the conceptual updates on oncolytic virotherapy and immunotherapy in cancer, and the development of strategies to enhance the virus-mediated anti-tumor immune response, including: (1) arm OVs with cytokines to modulate innate and adaptive immunity; (2) combining OVs with immune checkpoint inhibitors to release T cell inhibition; (3) combining OVs with immune co-stimulators to enhance T cell activation. Future studies need to be enforced on developing strategies to augment the systemic effect on metastasized tumors.

89Zr-labeled CEA-targeted IL-2 variant immunocytokine in patients with solid tumors: CEA-mediated tumor accumulation and role of IL-2 receptor-binding

Cergutuzumab amunaleukin (CEA-IL2v) is an immunocytokine directed against carcinoembryonic antigen (CEA) containing an IL2v-moiety with abolished IL-2 receptor (IL-2R) α binding. We describe the biodistribution and tumor accumulation of ⁸⁹Zr-labeled CEA-IL2v. Twenty-four patients with advanced solid CEA positive (CEA+) or negative (CEA−) tumors received CEA-IL2v 6 mg (4 CEA+; 3 CEA−), 20 mg (9 CEA+), or 30 mg (4 CEA+; 4 CEA−) biweekly. In cycle 1, 2 mg of the total dose comprised ⁸⁹Zr-CEA-IL2v (50 MBq) and serial ⁸⁹Zr-PET imaging was conducted. Four CEA+ patients with visually confirmed ⁸⁹Zr-CEA-IL2v tumor accumulation at 20 mg had repeated ⁸⁹Zr-PET imaging during cycle 4. ⁸⁹Zr-CEA-IL2v immuno-PET demonstrated preferential drug accumulation in CEA+ tumors (%ID/mL_peak CEA− 3.6 × 10⁻³ vs. CEA+ 6.7 ×∙10⁻³). There was a non-significant trend towards dose-dependent tumor uptake, with higher uptake at doses ≥20 mg. Biodistribution was dose- and CEA-independent with major accumulation in lymphoid tissue compatible with IL-2R binding. Reduced exposure and reduced tumor accumulation (%ID/mL_peak 57% lower) on cycle 4 vs. cycle 1 was consistent with peripheral expansion of immune cells. The findings of this immune PET imaging study with ⁸⁹Zr-CEA-IL2v support the therapeutic concept of CEA-IL2v, confirming selective and targeted tumor accumulation with this novel immunocytokine.

Intralesional therapy as a treatment for locoregionally metastatic melanoma

INTRODUCTION

The emergence of novel intralesional therapies have dramatically changed the treatment landscape for melanoma. The heterogeneous presentation of melanoma continues to pose challenges for clinicians, especially when dealing with advanced locoregional disease. Intralesional therapies have the benefit of causing local tumor destruction, while minimizing systemic toxicity. Moreover, the integration of immunotherapeutic agents into intralesional compounds has resulted in the additional benefit of a bystander effect, whereby untreated distant lesions also derive a benefit from treatment. Intralesional therapy has assumed an important role in the management of unresectable, locoregional disease for melanoma. Areas covered: Multiple intralesional agents have been studied over the years, with only a few demonstrating promising results. This review will provide an overview of the different intralesional agents for melanoma. Mechanisms of action, clinical efficacy, and side effects will be the primary focus. Expert commentary: Treatment options for advanced melanoma continue to evolve. Attractive new therapies delivered by an intralesional route has demonstrated promising results, with minimal side effects. The ideal treatment strategy for melanoma will remain a multimodal approach; intralesional therapy provides an additional tool in the treatment armamentarium for melanoma.

Developments in Intralesional Therapy for Metastatic Melanoma

BACKGROUND

Locoregional advanced melanoma poses a complex clinical challenge that requires a multidisciplinary, patient-centered approach. Numerous agents have been studied for their suitability as intralesional therapy in the past decades, but few have successfully completed phase 3 clinical trial testing.

METHODS

The relevant medical literature was searched for articles regarding use of intralesional therapies in metastatic melanoma. Therapies with data from phase 2 or higher studies were selected for review. This review also summarizes the mechanisms of action, adverse-event profiles, and clinical data for these agents.

RESULTS

Intralesional therapies demonstrate promising effects in select patients with advanced melanoma. The optimal approach should be individually tailored and consist of a combination of intralesional therapies, regional perfusions, systemic immunotherapies, targeted therapies, and surgery, if necessary.

CONCLUSIONS

Due to its relatively good local response rates and tolerable adverse-event profile, intralesional therapy may be a treatment option for select patients with unresectable, locally advanced or metastatic melanoma.

Intralesional therapy for metastatic melanoma

INTRODUCTION

Intralesional therapy for metastatic melanoma has some advantages over systemic therapy. Local drug administration allows for delivery of an increased concentration of the agent and reduced systemic exposure, thereby increasing local efficacy and limiting toxicity. Moreover, since in vivo tumor nodules contain the tumor antigens, this tumor tissue may serve as an autologous vaccine to induce systemic immunity. This so-called 'bystander effect', where uninjected distant lesions exhibit a response, has been reported in select intralesional therapy trials.

AREAS COVERED

This review will give an overview of the working mechanisms, clinical evidence and side effects for available intralesional and topical therapies and summarize the most recent developments in this field.

EXPERT OPINION

The ideal treatment approach for locoregionally advanced melanoma should be multidisciplinary and tailored to the patient, taking into consideration patient-related, tumor-related factors (such as location, tumor burden, mutation status) and previous treatments received. It will likely not be a single therapy, but rather a combination of injectable treatments, regional perfusions and systemic therapies.

Durable benefit and the potential for long-term survival with immunotherapy in advanced melanoma

Historically, the median overall survival for patients with stage IV melanoma was less than 1 year and the 5-year survival rate was ∼10%. Recent advances in therapy have raised 5-year survival expectations to ∼20%. Notably, a subset of melanoma patients who receive immunotherapy with high-dose interleukin-2, and now ipilimumab, can achieve long-term survival of at least 5 years. A major goal in melanoma research is to increase the number of patients who experience this overall survival benefit. In this review, we discuss the attributes of immunotherapy and newer targeted agents, and consider how combination strategies might improve the chances of achieving durable benefit and long-term survival. We also discuss three areas that we believe will be critical to making further advances in melanoma treatment. To better understand the clinical profile of patients who achieve long-term survival with immunotherapy, we first present data from ipilimumab clinical trials in which a subset of patients experienced durable responses. Second, we discuss the limitations of traditional metrics used to evaluate the benefits of immunotherapies. Third, we consider emerging issues that clinicians are currently facing when making treatment decisions regarding immunotherapy. A better understanding of these novel treatments may improve survival outcomes in melanoma, increase the number of patients who experience this overall survival benefit, and inform the future use of these agents in the treatment of other cancer types.

Treatment of in-transit melanoma with intra-lesional interleukin-2: a systematic review

BACKGROUND

Several phase II studies have assessed intra-lesional interleukin-2 (IL-2) for the treatment of in-transit melanoma. This systematic review addresses the efficacy and side effect profile of IL-2.

METHODS

MEDLINE, EMBASE, Cochrane Library, and Google Scholar databases were searched from 1980 to 2012 for studies evaluating the clinical response to IL-2 for in-transit melanoma. Titles and abstracts were screened by two independent researchers for suitability using predetermined inclusion and exclusion criteria. A modified quality assessment tool for observational studies was used. Data were pooled and analyzed to determine lesion and patient response rates.

RESULTS

Forty-nine studies were identified. Forty-three did not meet inclusion criteria, leaving six observational trials. Heterogeneity was seen in IL-2 dosage and treatment interval. Response rate was variable as well. Overall, 2,182 lesions and 140 patients were treated in these six studies. Pooling the lesions, complete response was seen in 78%. Pooling subjects, 50% achieved a complete response. Treatment was generally well tolerated, with localized pain and swelling, and mild flu-like symptoms. There were only three grade 3 adverse events reported, including rigors, headache, and fever with arthralgia.

CONCLUSIONS

Intra-lesional IL-2 safely and effectively provides locoregional control of in-transit melanoma.

Melanoma immunotherapy

Immunotherapy is a cornerstone in the treatment of melanoma, and is intended to modulate the host immunity against the tumor. Immunotherapy can be used in an adjuvant setting, after complete surgical excision in patients with a high risk of disease relapse and as a treatment in advanced (unresectable or metastatic) stages. Development of novel therapeutic approaches and the optimization of existing therapies hold a great promise in the field of melanoma therapy research. Different clinical trials are ongoing, and immunotherapy is showing the ability to confirm durable clinical benefits in selected groups of melanoma patients. The aim of this review is to summarize different types of immunotherapy agents, as well as to discuss different strategies, complementary regimens, and possible biomarkers of response to the treatment.

Immune alterations in malignant melanoma and current immunotherapy concepts

INTRODUCTION

Malignant melanoma is a highly aggressive, immunogenic tumor that has the ability to modulate the immune system to its own advantage. Patients with melanoma present numerous cellular immune defects and cytokine abnormalities, all leading to suppression of the host anti-tumor immune response. Innovative treatment strategies can be achieved through employing our knowledge of the melanoma-induced immune alterations.

AREAS COVERED

The authors review comprehensively the immune abnormalities in individuals with melanoma, and provide a summary of currently available melanoma immunotherapy agents that are currently on the market or undergoing clinical trials.

EXPERT OPINION

Ipilimumab, a monoclonal antibody directed against the CTLA-4, is one of the current forefront treatment strategies in malignant melanoma. Novel immunomodulating agents have shown clear activity in patients with malignant melanoma. These include anti-PD-1 and anti-PD-1 ligand antibodies that may soon become important items in the anti-melanoma armamentarium. Combinations of different immunotherapy agents, between themselves or with other agents, are currently being studied in an attempt to further enhance the antineoplastic effect in patients with malignant melanoma.

Promoting immunity during chronic infection--the therapeutic potential of common gamma-chain cytokines

The continued global burden wrought by chronic infectious disease is unrelenting. Current therapies have curbed the severity of disease for patients, but Human Immunodeficiency Virus (HIV) and Hepatitis B (HBV) infection remain incurable and Mycobacterium tuberculosis (MTB) is rapidly becoming resistant to our existing antibiotics. Much attention has been given to enhancing T cell immunity through the use of certain common gamma-chain cytokines, which have proven to be essential and necessary for T cell survival and function. This article reviews the pre-clinical and clinical literature surrounding IL-2, IL-7, IL-15 and IL-21 and we comment on the potential therapeutic promise of these cytokines as adjuvant treatments for chronic infectious diseases.

Newer developments in the immunotherapy of malignant melanoma

Individuals with malignant melanoma present a variety of immune abnormalities including but not limited to cellular immune dysfunction, antigen presentation deficits, and cytokine production defects. Therefore, enhancing the immune system potential represents an appealing avenue for melanoma therapy. The authors review the immune therapies currently in clinical use as well as the most promising immunotherapy candidates. Ipilimumab, a monoclonal antibody against the CTLA-4, was approved for the therapy of advanced melanoma in 2011. In addition, sizeable anti-melanoma activity has recently been shown with the use of other agents including anti-PD-1/anti-PD-1 ligand antibodies. Consequently, these experimental immunotherapy agents may soon become important items in the anti-melanoma armamentarium.

Clinical study of autologous cytokine-induced killer cells for the treatment of elderly patients with diffuse large B-cell lymphoma

To evaluate the effectiveness and safety of autologous cytokine-induced killer (CIK) cells in elderly patients with diffuse large B-cell lymphoma. Peripheral blood mononuclear cells (PBMC) were isolated from nine elderly patients with diffuse large B-cell lymphoma. PBMCs were augmented by priming with interferon gamma (IFN-γ) followed by IL-2 and monoclonal antibody (mAb) against CD3. Autologous CIK cells (range 5 × 10(9)-1 × 10(10)) were then infused back to individual patients; infusion was repeated every 4 weeks for 32 weeks (eight cycles). Patients were assessed for changes in lymphocyte subgroup, tumor-related biological parameters, imaging characteristics, the condition of remission, quality of life (QOL), and survival. Prior to CIK infusion, two patients were in complete remission and seven patients were in partial remission. After autologous CIK cell transfusions, the proportion of CD3+, CD3+CD8+, and CD3+CD56+ cells were significantly increased compared with baseline (P < 0.05); whereas serum levels of β2-microglobulin and LDH were significantly decreased (P < 0.05). The lymphoma symptoms were reduced and QOL was improved (P < 0.05) in all patients. All patients achieved complete remission at study endpoint. No adverse reactions were reported. Autologous CIK cell immunotherapy is safe and efficacious for the treatment of elderly patients with diffuse large B-cell lymphoma.

Spotlight on histamine dihydrochloride in acute myeloid leukaemia

Histamine dihydrochloride (Ceplene®) is a synthetic derivative of the biogenic amine histamine. Histamine dihydrochloride inhibits the formation of reactive oxygen species that suppress the activation of T cells and natural killer (NK) cells. When given in addition to the cytokine interleukin (IL)-2, histamine dihydrochloride enables the activation of T cells and NK cells by IL-2, resulting in the killing of cancer cells, including those of acute myeloid leukaemia (AML). In a large, 3-year, randomized, open-label, multicentre, phase III trial in adult patients with AML in first or subsequent remission, those who received subcutaneous histamine dihydrochloride and concomitant subcutaneous IL-2 as maintenance therapy had a significantly longer leukaemia-free survival (LFS; primary endpoint) than patients receiving no treatment. This difference was also shown for the subgroup of patients in first remission. The between-group difference in overall survival (OS) was not significant, although this trial was not powered to detect such a difference. Histamine dihydrochloride and IL-2 therapy had an acceptable tolerability profile in patients in the phase III trial. The majority of reported adverse events were of grade 1 or 2 severity. The most commonly reported grade 3 adverse events with active treatment were thrombocytopenia, headache, neutropenia, pyrexia, eosinophilia and diarrhoea; grade 4 adverse events were thrombocytopenia and leukopenia not otherwise specified. Serious adverse events were mostly relapse related. Histamine dihydrochloride and IL-2 as maintenance therapy significantly prolonged LFS compared with no treatment and had an acceptable tolerability profile in a large phase III trial in patients with AML. Although some issues remain to be addressed, most notably the effects of therapy on OS and the efficacy of treatment in older patients (who represent the majority of AML patients), histamine dihydrochloride in addition to IL-2 appears to be a useful maintenance therapy option for adult patients with AML in remission.

Effective melanoma immunotherapy with interleukin-2 delivered by a novel polymeric nanoparticle

Interleukin-2 (IL-2) has been shown to possess antitumor activity in numerous preclinical and clinical studies. However, the short half-life of recombinant IL-2 protein in serum requires repeated high-dose injections, resulting in severe side effects. Although adenovirus-mediated IL-2 gene therapy has shown antitumor efficacy, the host antibody response to adenoviral particles and potential biosafety concerns still obstruct its clinical applications. Here we report a novel nanopolymer for IL-2 delivery, consisting of low molecular weight polyethylenimine (600 Da) linked by β-cyclodextrin and conjugated with folate (named H1). H1 was mixed with IL-2 plasmid to form H1/pIL-2 polyplexes of around 100 nm in diameter. Peritumoral injection of these polyplexes suppressed the tumor growth and prolonged the survival of C57/BL6 mice bearing B16-F1 melanoma grafts. Importantly, the antitumor effects of H1/pIL-2 (50 μg DNA) were similar to those of recombinant adenoviruses expressing IL-2 (rAdv-IL-2; 2 × 10(8) pfu). Furthermore, we showed that H1/pIL-2 stimulated the activation and proliferation of CD8+, CD4+ T cell, and natural killer cells in peripheral blood and increased the infiltration of CD8+, CD4+ Tcells, and natural killer cells into the tumor environment. In conclusion, these results show that H1/pIL-2 is an effective and safe melanoma therapeutic with an efficacy comparable to that of rAdv-IL-2. This treatment represents an alternative gene therapy strategy for melanoma.

Modified DT-IL2 fusion toxin targeting uniquely IL2Ralpha expressing leukemia cell lines - Construction and characterization

Immunotoxins are fusion proteins of modified toxin conjugated to tumor cell selective ligand. Denileukin diftitox approved by FDA for treatment of CTCL is diphtheria toxin (DT)/IL2 fusion protein targeted to high affinity IL2R. Here, we have attempted to target the more uniquely expressed low affinity IL2R (IL2Ralpha). We designed four immunotoxins, SPRSV1 was designed to code for a single protein of DT (390) and IL2 (133) without any extra amino acids at the junction. SPRSV2 was designed to selectively target low affinity IL2R, it codes for DT (390) and IL2 (69). We also constructed SPRSV3 encoding for only DT (390) without any ligand, as negative control and SPRSV4 was designed similar to commercial equivalent denileukin diftitox, it codes for DT (387) and IL2 (133) with His at the junction. The cytotoxic activities of these immunotoxins were tested in various cell lines, cell lines lacking IL2R expression and healthy MNC were used as controls. The activities of SPRSV1 and SPRSV2 were comparable to that of SPRSV4. SPRSV2 exhibited potent cytotoxicity effectively targeted to alpha subunit of IL2R on various leukemia cell lines. Our studies also showed a negative correlation between CD25 expression and percentage cell viability after treatment with immunotoxins.

The ruthenium complex cis-(Dichloro)Tetraammineruthenium(III) chloride presents immune stimulatory activity on human peripheral blood mononuclear cells

Ruthenium compounds in general are well suited for medicinal applications. They have been investigated as immunosuppressants, nitric oxide scavengers, antimicrobial agents, and antimalarials. The aim of this study is to evaluate the immunomodulatory activity of cis-(dichloro)tetraammineruthenium(III) chloride (cis-[RuCl(2)(NH(3))(4)]Cl) on human peripheral blood mononuclear cells (PBMC). The cytotoxic studies performed here revealed that the ruthenium(III) complex presents a cytotoxic activity towards normal human PBMC, only at very high concentration. Results also showed that cis-[RuCl(2)(NH(3))(4)]Cl presents a dual role on PBMC stimulating proliferation and interleukin-2 (IL-2) production at low concentration and inducing cytotoxicity, inability to proliferate, and inhibiting IL-2 production at high concentration. The noncytotoxic activity of cis-[RuCl(2)(NH(3))(4)]Cl at low concentration towards PBMC, which correlates with the small number of annexin V positive cells and also the absence of DNA fragmentation, suggest that this compound does not induce apoptosis on PBMC. For the first time, we show that, at low concentration (10-100 microg L(-1)), the cis-[RuCl(2)(NH(3))(4)]Cl compound induces peripheral blood lymphocytes proliferation and also stimulates them to IL-2 production. These results open a new potential applicability of ruthenium(III) complexes as a possible immune regulatory compound acting as immune suppressor at high concentration and as immune stimulator at low concentration.

Sequential administration of GM-CSF (Sargramostim) and IL-2 +/- autologous vaccine as adjuvant therapy in cutaneous melanoma: an interim report of a phase II clinical trial

Granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-2 (IL-2) are 2 cytokines with distinct mechanisms of action that complement one another in the adjuvant management of melanoma. Forty-five patients with high-risk melanoma were enrolled in an open-label, single-arm, phase II clinical trial to examine the safety, tolerability, and effectiveness of this combination. After potentially curative surgery, each patient received 12 months of GM-CSF 125 microg/m2/d subcutaneously (SC) for 14 days followed by IL-2, 9 million IU/m2/d SC for 4 days (given every other cycle from months 7-12), followed by 10 days of no treatment. In addition, patients who had tumors yielding an adequate number of live cells received autologous melanoma vaccines. For months 13-24, patients received only GM-CSF 250 microg/m2 twice weekly. This is an interim analysis based on the 45 enrolled patients with a median of 15.9 months follow-up (range, 1-50 months). Thirty-two patients are alive: 9 of 13 with stage IV resected melanoma, 16 of 25 with stage III disease, and 7 of 7 with stage II disease. Twelve died of the disease, and one due to stroke. Adjuvant use of sequential GM-CSF and IL-2 +/- autologous vaccine was well tolerated with good patient compliance and seemed to benefit high-risk patients with surgically resected melanoma.

Current immunotherapeutic strategies in breast cancer

Despite significant advances in the administration of combination cytotoxic chemotherapy, the overall 5-year survival rate is about 75% for a woman who has node-positive breast cancer, and metastatic disease is considered incurable. Recent advances in our understanding of the immune system have led to the hope that manipulation of this organ system could be used as a cancer treatment. Strategies that have been used in the immune therapy of breast cancer include the administration of exogenous cytokines, vaccines, and humanized monoclonal antibodies (mAb). Each of these approaches is discussed in turn in this article.

Phenotype and function of dendritic cells and T-lymphocyte polarization in the human colonic mucosa and adenocarcinoma

AIM

To evaluate the status of activation of the intestinal dendritic cells (DCs) and T lymphocytes (T cells) from surgical specimens of human colon and adenocarcinoma, and the potential effect of administration of interleukin 2 (IL-2).

METHODS

Patients undergoing colectomy for cancer were randomized to receive subcutaneous IL-2 (12million UI/day) (treated group; n=10) for 3days before operation or no treatment (control group, n=10). DCs and T cells were isolated and purified from the lamina propria (LP) of segments of normal colon and adenocarcinoma of both groups. Cell phenotype was determined by expression of membrane receptors. Interaction between DC and T cells was assesses by a mixed leukocyte reaction using naïve T cells co-cultured with DCs. CD4+ T-cell polarization was studied by intracellular staining with monoclonal antibodies for interleukin-4 and interferon-gamma.

RESULTS

CD4+ T cells were significantly less in tumour than in LP (p<0.05) in both treated and control groups. IL-2 did not modify the number of any of the T-cell subsets analysed. In contrast, T cells isolated from LP and neoplasm of treated patients produced more interferon-gamma and less interleukin-4 (p<0.05 vs. controls). IL-2 administration significantly increased (p<0.05) the number of mature, myeloid and plasmocytoid DCs compared to controls. Allogeneic naïve T cells were polarized toward a Th1 type of response which appeared to be mediated by IL-2 activated DCs.

CONCLUSIONS

systemic IL-2 treatment may have immunomodulatory properties on intestinal DC maturation and drive a Th1 mediated anti-neoplastic response.

Inhibitory effects of fusarochromanone on melanoma growth

Fusarochromanone is a toxic metabolite produced by Fusarium equiseti, a fungus present in decaying cereal plants in northern latitudes; it has been detected in various food grains. Fusarochromanone has been shown to have both stimulatory and inhibitory effects on various mammalian cells, depending on the concentration used. Whether these cytotoxic effects can be used in the clinical treatment of tumors remains to be established. Here, we evaluated the effects of fusarochromanone on the growth of human melanoma cells both in vitro and in vivo. In vitro, low concentrations (0.1-1 nmol/l) of fusarochromanone were found to be cytotoxic to many melanoma cell lines. In contrast, growth of normal melanocytes was inhibited only at much higher fusarochromanone concentrations (100-200 nmol/l). In vivo, the growth of melanoma cells implanted subcutaneously in immuno-compromised mice was significantly (P<0.05) reduced by daily administration of fusarochromanone. Immunohistological analyses indicated a significant (P<0.05) increase in the expression of active caspase-3 in tumor masses of mice treated with fusarochromanone, compared with controls. Together, these observations show that fusarochromanone increased apoptosis of tumor cells and reduced tumor growth in vivo. Therefore, the effects of fusarochromanone warrant further investigation as an adjuvant molecule to prevent growth and recurrence of melanomas.

Enhancement of the anti-leukemic activity of cytokine induced killer cells with an anti-CD19 chimeric receptor delivering a 4-1BB-ζ activating signal

OBJECTIVE

There is growing interest in the use of cytokine-induced killer (CIK) cells in cancer therapy. In this study, we sought to maximize the antileukemic activity of anti-CD19 receptor-modified CIK cells against B-lineage acute lymphoblastic leukemia (ALL).

MATERIALS AND METHODS

CIK cells were transduced with retroviral vectors carrying different types of anti-CD19 chimeric receptors: anti-CD19-zeta, anti-CD19-DAP10, anti-CD19-4-1BB-zeta, and anti-CD19-CD28-zeta. A truncated form of the receptor was used as a control. Transduced CIK cells were then analyzed for their cytotoxic activity against ALL cells and for their capability to proliferate and to release cytokines after ALL encounter.

RESULTS

CIK cells were efficiently transduced with all the anti-CD19 retroviral vectors. Anti-CD19 receptor expression conferred powerful killing activity against ALL cells. However, there were clear advantages when receptors containing the co-stimulatory molecules 4-1BB or CD28 were transduced. Such cells had significantly more potent cytotoxicity than cells expressing the anti-CD19-zeta or anti-CD19-DAP10. Moreover, the presence of 4-1BB or CD28 in the receptor increased the production of interleukin (IL)-2, tumor necrosis factor (TNF)-alpha, TNF-beta, IL-5, IL-6, and IL-8 elicited by coculture with ALL cells. Notably, anti-CD19-4-1BB-zeta CIK cells secreted particularly low levels of interleukin-10 and proliferated strongly after contact with ALL cells.

CONCLUSIONS

Anti-CD19 chimeric receptors delivering primary and costimulatory signals render CIK cells powerfully cytotoxic against ALL cells and induce secretion of immunostimulatory cytokines and proliferation. These results support the testing of genetically modified CIK cells in clinical trials.

Enhancing Antitumor Immunity: Combining IL-12 With TGFβ1 Antagonism

With respect to CD8 effector T cells, interleukin-12 (IL-12) and transforming growth factor beta (TGFbeta) are 2 cytokines that exert opposing effects. IL-12 promotes antitumor immune responses by augmenting activated CD8 T-cell proliferation and interferon-gamma secretion. Conversely, TGFbeta generates a permissive environment for cancer growth, in part by antagonizing the effects of immunomodulatory cytokines, including IL-12. We demonstrate that TGFbeta-resistant T cells are capable of sustaining IL-12-induced mitogenesis and interferon-gamma secretion in a TGFbeta-rich milieu. Furthermore, in 2 murine tumor models associated with high TGFbeta1 levels in the local microenvironment, treatment with IL-12 and adoptively transferred TGFbeta-resistant T cells provided improved survival times. These results suggest that combining IL-12 with TGFbeta neutralization strategies may be effective in enhancing antitumor immune responses.

Inducing a mode of NK-resistance to suppression by stress and surgery: a potential approach based on low dose of poly I-C to reduce postoperative cancer metastasis

Perioperative suppression of NK activity has been suggested to compromise host resistance to tumor progression. Here, we sought to develop a clinically applicable preoperative regimen to prevent immunosuppression and promotion of metastasis by stress or surgery. The synthetic ds-RNA, poly I-C, was used in vivo in F344 rats, based on its alleged in vitro ability to protect immunocytes from suppression by cAMP elevating agents. Different regimens of poly I-C were studied in controls and in rats subjected to a pharmacological stressor, swim stress, or surgical stress. Resistance to lung experimental metastasis of the syngeneic non-immunogenic MADB106 mammary adenocarcinoma was assessed. Numbers of circulating and marginating-pulmonary NK cells and their cytotoxicity against the MADB106 and YAC-1 target lines were also studied. Our findings established a regimen of repeated low-dose poly I-C administration with minimal side effects (0.2mg/kg i.p. 5, 3, and 1day before tumor inoculation). This regimen, while hardly affecting resistance levels in non-stressed animals, prevented all stressors from promoting metastases. These beneficial effects occurred in the presence of a primary tumor and in both sexes. Poly I-C increased the numbers of NK cells, and, on a per NK cell basis, while not increasing cytotoxicity, profoundly protected marginating-pulmonary NK cells from suppression by surgery. This study suggests a non-toxic clinically translatable prophylactic use of poly I-C to target the critical perioperative period. By increasing the number of marginating-pulmonary NK cells, and by transforming them into a mode of resistance to immunosuppression, this approach may reduce postoperative metastasis in cancer patients.

Applications of carrier erythrocytes in delivery of biopharmaceuticals

Carrier erythrocytes, resealed erythrocytes loaded by a drug or other therapeutic agents, have been exploited extensively in recent years for both temporally and spatially controlled delivery of a wide variety of drugs and other bioactive agents owing to their remarkable degree of biocompatibility, biodegradability and a series of other potential advantages. Biopharmaceuticals, therapeutically significant peptides and proteins, nucleic acid-based biologicals, antigens and vaccines, are among the recently focused pharmaceuticals for being delivered using carrier erythrocytes. In this article, the potential applications of erythrocytes in drug delivery have been reviewed with a particular stress on the studies and laboratory experiences on successful erythrocyte loading and characterization of the different classes of biopharmaceuticals.