Single-agent interleukin-2 in the treatment of metastatic melanoma

Nanoparticle Delivery of Immunostimulatory Agents for Cancer Immunotherapy

Immunostimulatory agents, including adjuvants, cytokines, and monoclonal antibodies, hold great potential for the treatment of cancer. However, their direct administration often results in suboptimal pharmacokinetics, vulnerability to biodegradation, and compromised targeting. More recently, encapsulation into biocompatible nanoparticulate carriers has become an emerging strategy for improving the delivery of these immunotherapeutic agents. Such approaches can address many of the challenges facing current treatment modalities by endowing additional protection and significantly elevating the bioavailability of the encapsulated payloads. To further improve the delivery efficiency and subsequent immune responses associated with current nanoscale approaches, biomimetic modifications and materials have been employed to create delivery platforms with enhanced functionalities. By leveraging nature-inspired design principles, these biomimetic nanodelivery vehicles have the potential to alter the current clinical landscape of cancer immunotherapy.

Cancer immunotherapy using the Fusion gene of Sendai virus

Inactivated Sendai virus particle (or hemagglutinating virus of Japan envelope; HVJ-E) has been previously reported to possess antitumour properties that activate antitumour immunity. Two glycoproteins, fusion (F) and hemagglutinin-neuraminidase (HN), are present on the surface of HVJ-E. HN is necessary for binding to receptors such as acidic gangliosides, and F induces membrane fusion by associating with membrane lipids. We previously reported that liposomes reconstituted with F but not HN showed antitumour activity by inducing IL-6 secretion in dendritic cells (DCs), suggesting that F protein is capable of eliciting antitumour activity. Here, we attempted to deliver F gene into tumour tissue in mice by electroporation and demonstrated that F gene therapy retarded tumour growth, increased CD4⁺ and CD8⁺ T-cell infiltration into tumours and induced tumour-specific IFN-γ T-cell response. However, neutralisation of IL-6R signalling did not impact F plasmid-mediated antitumour effect. Instead, we found that F plasmid treatment resulted in a significant increase in the secretion of the chemokine RANTES (regulated upon activation, normal T cell expressed and secreted) by tumour-infiltrating T cells. Neutralising antibody against RANTES abolished the antitumour effect of F plasmid treatment in a dose-dependent manner. Thus, F gene therapy may show promise as a novel therapeutic for single or combined cancer immunotherapy.

Cancer Immune Checkpoint Inhibitor Therapy and the Gut Microbiota

The past decade has seen tremendous advances in both our understanding of cancer immunosuppressive microenvironments and colonic bacteria facilitated by immune checkpoint inhibitor antibodies and next generation sequencing, respectively. Because an important role of the host immune system is to communicate with and regulate the gut microbial community, it should not come as a surprise that the behavior of one is coupled to the other. In this review, we will attempt to dissect some of the studies demonstrating cancer immunotherapy modulation by specific gut microbes and discuss possible molecular mechanisms for this effect.

Advanced stage melanoma therapies: Detailing the present and exploring the future

Metastatic melanoma therapies have proliferated over the last ten years. Prior to this, decades passed with only very few drugs available to offer our patients, and even then, those few drugs had minimal survival benefits. Many treatment options emerged over the last ten years with diverse mechanisms of action. Further, combination regimens have demonstrated superiority over monotherapy, especially for targeted agents. Each therapeutic combination possesses different advantages and side effect profiles. In this review, we outline the United States Food and Drug Administration-approved melanoma treatment agents and therapies currently in clinical development, focusing on combination approaches.

Tailoring the Treatment of Melanoma: Implications for Personalized Medicine

Oncology has been revolutionized by the ability to selectively inhibit the growth of cancerous cells while ostensibly avoiding the disruption of proteins and pathways necessary for normal cellular function. This paradigm has triggered an explosion of targeted therapies for cancer, creating a burgeoning billion-dollar industry of small molecules and monoclonal antibodies [1]. Largely due to these new treatments, spending on cancer pharmaceuticals has surpassed $100 billion worldwide [2]. In particular, the treatment of melanoma, a deadly and fast-spreading form of skin cancer, has been transformed by these new targeted therapies. In this mini-review, we summarize the progress made in the field of personalized treatment of melanoma, with an emphasis on targeted therapies. We then outline future directions for treatment, including novel cell-mediated therapies and new potential targets.

Evolving Concepts: Immunity in Oncology from Targets to Treatments

Cancer is associated with global immune suppression of the host. Malignancy-induced immune suppressive effect can be circumvented by blocking the immune checkpoint and tip the immune balance in favor of immune stimulation and unleash cytotoxic effects on cancer cells. Human antibodies directed against immune checkpoint proteins: cytotoxic T lymphocytes antigen-4 (CTLA-4) and programmed death-1 (PD-1), programmed death-ligand 1 (PD-L1), have shown therapeutic efficacy in advanced melanoma and non-small-cell lung cancer and other malignancies. Immune check point blockade antibodies lead to diminished tolerance to self and enhanced immune ability to recognize and eliminate cancer cells. As a class these agents have immune-related adverse events due to decreased ability of effector immune cells to discriminate between self and non-self. Seventy percent of patients participating in clinical trials have experienced anticancer activities and varying degrees of immune mediated dose-limiting side effects.

TRIB2 as a biomarker for diagnosis and progression of melanoma

Malignant melanoma is the most deadly form of skin cancer. There is a critical need to identify the patients that could be successfully treated by surgery alone and those that require adjuvant treatment. In this study, we demonstrate that the expression of tribbles2 (TRIB2) strongly correlates with both the presence and progression of melanocyte-derived malignancies. We examined the expression of TRIB2 in addition to 12 previously described melanoma biomarkers across three independent full genome microarray studies. TRIB2 expression was consistently and significantly increased in benign nevi and melanoma, and was highest in samples from patients with metastatic melanoma. The expression profiles for the 12 biomarkers were poorly conserved throughout these studies with only TYR, S100B and SPP1 showing consistently elevated expression in metastatic melanoma versus normal skin. Strikingly we confirmed these findings in 20 freshly obtained primary melanoma tissue samples from metastatic lesions where the expression of these biomarkers were evaluated revealing that TRIB2 expression correlated with disease stage and clinical prognosis. Our results suggest that TRIB2 is a meaningful biomarker reflecting diagnosis and progression of melanoma, as well as predicting clinical response to chemotherapy.

The effect of vitamin D on vaginal atrophy in postmenopausal women

BACKGROUND

Most of the women suffer from vaginal atrophy and dryness, and therefore, efficient and safe treatment is needed to improve vaginal lubrication. Vitamin D has several important functions which may be effective in proliferation and repair of the epithelial tissue. This study aimed to evaluate the effect of vitamin D vaginal suppositories on maturation index, pH, and dryness in postmenopausal women.

MATERIALS AND METHODS

Women were enrolled in this double-blind clinical trial, in whom menopause occurred at least one year ago. Those women who had an abnormal Papanicolaou smear, had undergone hormonal treatment, or have had vaginal infection in the previous year were excluded. Forty-four women who found eligible were randomized into two equal groups, the treatment and control groups, which received vitamin D and placebo vaginal suppository daily for 8 weeks, respectively. Vaginal pH and maturation value were measured at the beginning and end of the study. Pain, dryness, and paleness were assessed before treatment and at the end of the 2, 4, and 8 weeks of treatment.

RESULTS

In the treatment group, the number (Mean ± SD) of superficial cells increased (69.76 ± 12.4) and vaginal pH decreased (1.42 ± 0.67) significantly compared to the control group after 56 days. The mean pain significantly reduced after 8 weeks in the treatment group (1.23 ± 0.53) compared to the control group 1.95 ± 0.74 (P < 0.001). The mean of dryness and paleness reduced significantly in the treatment group versus control at 56 days.

CONCLUSIONS

Vitamin D is effective in improving the maturation index and decreased the pH and dryness of the vaginal atrophy due to menopause.

Sequential immune monitoring in patients with melanoma and renal cell carcinoma treated with high-dose interleukin-2: immune patterns and correlation with outcome

Interleukin-2 (IL-2) therapy leads to clinically relevant responses in 10-16 % of patients with metastatic melanoma (MMEL) or 10-30 % of patients with metastatic renal cell carcinoma (MRCC). To date, no biomarkers have been validated to identify patients who are likely to respond. We hypothesized that changes in T cell subset distribution in patients undergoing IL-2 therapy may correlate with treatment outcomes. Immune profiles of 64 patients (27-MMEL, 37-MRCC) were evaluated using flow cytometry at baseline, during (≥three doses) and at the end of treatment cycle (30 ± 6 h after last dose), through two courses of IL-2 therapy. Changes in distribution and phenotype of circulating CD4 and CD8 lymphocyte subsets were compared (1) based on cancer types and (2) intra-patient during the course of the IL-2 therapy. Exploratory analysis of immunologic profiles was also performed based on treatment outcome. Independent of cancer type, IL-2 led to a transient decrease of circulating effector lymphocytes, while regulatory T cells gradually increased. Interleukin-2 differentially affected a subset of CD8 T cell expressing Foxp3, depending on malignancy type. In MMEL patients, IL-2 gradually expanded circulating CD8 Foxp3+ cells; in MRCC patients, IL-2 transiently increased expression of CD103 and CCR4 homing markers. Monitoring of adaptive immune variables early on and during the course of IL-2 therapy revealed transient alterations in immune profiles, specific to MMEL and MRCC patients, related to immune balance (and ultimately response to IL-2 therapy) or T cell egress from the circulation.

Clinical practice guidelines and consensus statements in oncology--an assessment of their methodological quality

BACKGROUND

Consensus statements and clinical practice guidelines are widely available for enhancing the care of cancer patients. Despite subtle differences in their definition and purpose, these terms are often used interchangeably. We systematically assessed the methodological quality of consensus statements and clinical practice guidelines published in three commonly read, geographically diverse, cancer-specific journals. Methods Consensus statements and clinical practice guidelines published between January 2005 and September 2013 in Current Oncology, European Journal of Cancer and Journal of Clinical Oncology were evaluated. Each publication was assessed using the Appraisal of Guidelines for Research and Evaluation II (AGREE II) rigour of development and editorial independence domains. For assessment of transparency of document development, 7 additional items were taken from the Institute of Medicine's standards for practice guidelines and the Journal of Clinical Oncology guidelines for authors of guidance documents.

METHODS

Consensus statements and clinical practice guidelines published between January 2005 and September 2013 in Current Oncology, European Journal of Cancer and Journal of Clinical Oncology were evaluated. Each publication was assessed using the Appraisal of Guidelines for Research and Evaluation II (AGREE II) rigour of development and editorial independence domains. For assessment of transparency of document development, 7 additional items were taken from the Institute of Medicine's standards for practice guidelines and the Journal of Clinical Oncology guidelines for authors of guidance documents.

FINDINGS

Thirty-four consensus statements and 67 clinical practice guidelines were evaluated. The rigour of development score for consensus statements over the three journals was 32% lower than that of clinical practice guidelines. The editorial independence score was 15% lower for consensus statements than clinical practice guidelines. One journal scored consistently lower than the others over both domains. No journals adhered to all the items related to the transparency of document development. One journal's consensus statements endorsed a product made by the sponsoring pharmaceutical company in 64% of cases.

CONCLUSION

Guidance documents are an essential part of oncology care and should be subjected to a rigorous and validated development process. Consensus statements had lower methodological quality than clinical practice guidelines using AGREE II. At a minimum, journals should ensure that that all consensus statements and clinical practice guidelines adhere to AGREE II criteria. Journals should consider explicitly requiring guidelines to declare pharmaceutical company sponsorship and to identify the sponsor's product to enhance transparency.

Update on benefit of immunotherapy and targeted therapy in melanoma: the changing landscape

Malignant melanoma is on the rise. There have been recent advances in targeted agents and immunotherapies that have improved the management and treatment of patients with advanced melanoma. This review discusses the clinical efficacy and unique side effects of targeted immunotherapy and the role of predictive biomarkers in better selection of patients who would derive most benefit from specific treatments. Additionally, this review addresses concerns about the best sequencing algorithms for the currently available targeted agents. By thoroughly and extensively researching through PubMed and the American Society of Clinical Oncology, 69 published articles and abstracts were identified as addressing topics related to malignant melanoma and immunotherapy. The research was divided into subcategories discussing cytokine-based therapy, immunotherapy, molecularly targeted agents, other novel targeted agents, and combination regimens for malignant melanoma. New immune checkpoint inhibitors and targeted agents are able to improve immune-mediated regulatory effects against tumors and, specifically in advanced melanoma, are associated with improvement in overall survival. These new agents have distinct side effects that are often controlled and reversed with dose reductions and/or use of corticosteroids. Currently, there are clinical trials underway to assess the role of combination therapy, whereas other trials are focusing on devising algorithms to delineate how best to sequentially administer these drugs. Although there has been tremendous progress in the management of advanced melanoma with immunotherapy and targeted agents, there is still much to be learned about clinically useful predictive biomarkers and combination therapies as well as how to administer these agents safely.

Comparison of vascular leak syndrome in mice treated with IL21 or IL2

Interleukin 21 (IL21) is a T-cell-derived 4-helix-bundle cytokine that has sequence homology to the IL2 family. Recombinant human interleukin 2 (rIL2) is approved for the treatment of metastatic melanoma and renal cell carcinoma. However, toxicity of rIL2, including induction of vascular leak syndrome (VLS), has limited use of this cytokine to a small proportion of eligible patients. Both rIL2 and murine IL21 (mIL21) have potent antitumor efficacy in murine models. The purpose of the current study was to compare the ability of mIL21 and rIL2 to induce vascular leakage in a mouse model. Pulmonary and hepatic uptake of Evans blue dye, serum cytokine levels, spleen cell immunophenotype, and histologic changes in lung and liver were evaluated to detect VLS. High-dose (200 μg) rIL2 treatment induced vascular leakage in mice, evidenced by inflammatory cell infiltration and fluid extravasation into the lung and liver and increased levels of TNFα, IFNγ, IL5, MCP1, and IL6 in serum. In contrast, an equivalent dose of mIL21 resulted in minimal vascular leakage with no evidence of cytopenia or cytokine production. These results support the use of IL21 as a cancer immunotherapeutic agent, potentially providing an antitumor response without induction of VLS.

Reevaluating the concept of treating experimental tumors with a mixed bacterial vaccine: Coley's Toxin

Several decades after Coley's initial work, we here systematically analyzed tumoricidal as well as immunostimulatory effects of the historical preparation Coley's Toxin (CT), a safe vaccine made of heat-inactivated S. pyogenes and S. marcescens. First, by performing in vitro analysis, established human pancreatic carcinoma cell lines responded with dose- and time-dependent growth inhibition. Effects were attributed to necrotic as well as apoptotic cell death as determined by increased Caspase 3/7 levels, raised numbers of cells with sub-G1-DNA, and induced p21^waf expression, indicative for cell cycle arrest. Besides, CT effectively stimulated human peripheral blood leukocytes (huPBL) from healthy volunteers. Quantitative gene expression analysis revealed upregulated mRNA levels of selected Toll-like receptors. Flow cytometric phenotyping of CT-stimulated huPBLs identified raised numbers of CD25⁺-activated leukocytes. In vivo, repetitive, local CT application was well tolerated by animals and induced considerable delay of Panc02 tumors. However, systemic treatment failed to affect tumor growth. Antitumoral effects following local therapy were primarily accompanied by stimulation of innate immune mechanisms. Data presented herein prove that the historical approach of using killed bacteria as active immunotherapeutic agents still holds promise, and further careful preclinical analyses may pave the way back into clinical applications.

Unique antineoplastic profile of Saquinavir-NO, a novel NO-derivative of the protease inhibitor Saquinavir, on the in vitro and in vivo tumor formation of A375 human melanoma cells

We have recently shown that covalent attachment of the nitric oxide (NO) moiety to the HIV protease inhibitor Saquinavir (Saq) produced a qualitatively new chemical entity, named Saquinavir-NO (Saq-NO), with enhanced anticancer properties and reduced toxicity both in vitro and in vivo. The aim of this study was to address several unanswered questions both on the pharmacological profile of Saq-NO as well as on the in vivo role of NO in the oncogenesis of A375 human melanoma cells. To this end, we have evaluated here the impact of single and combined effects of Saq-NO, Saq, the NO-donor DETA NONOate and the iNOS inhibitor L-NAME on the in vitro as well as in vivo growth of the iNOS positive A375 cells. Our data confirm clear-cut evidence for a strong and powerful anti-melanoma action of Saq-NO that is not duplicable by the combined use of Saq and DETA NONOate. Surprisingly, but also in agreement with the complex and multifaceted role of endogenous NO in A375 cells, both DETA NONOate and L-NAME significantly suppressed the in vivo growth of xenotransplants.

Long-term survival in patients with metastatic melanoma treated with DTIC or temozolomide

BACKGROUND

Patients with metastatic melanoma typically have a poor outcome; however, a small proportion of patients achieve long-term survival (LTS). It is unclear how often LTS is related to sensitivity to chemotherapy.

METHODS

All patients with metastatic melanoma treated with either dacarbazine (DTIC) or temozolomide (TMZ) at the British Columbia Cancer Agency (BCCA) from January 1, 1988 to February 1, 2006 were identified through the BCCA pharmacy electronic database, which was then linked to the surveillance and outcomes unit to identify patients with LTS, defined as survival > or =18 months following chemotherapy.

RESULTS

In total, 397 patients were treated with either DTIC (n = 349) or TMZ (n = 48) and 43 patients (10.8%) were identified with LTS. Two additional patients with LTS were added prior to 1988 for a total of 45 patients. The 5-year overall and progression-free survival rates for patients with LTS were 33% and 16%, respectively. In total, 16% had a complete response (CR) to chemotherapy, which was the only factor identified that correlated with survival in the multivariate analysis. However, most patients with LTS had an incomplete response to chemotherapy.

CONCLUSIONS

LTS occurs in select patients who achieve a CR to chemotherapy. However, this occurs in only a minority of patients and, in most cases, the longer survival is likely the result of indolent disease biology or host factors.

Triphenylmethylamides (TPMAs): Structure-activity relationship of compounds that induce apoptosis in melanoma cells

Triphenylmethylamides (TPMAs) have been previously identified as compounds that arrest cells in the G1-phase of the cell cycle and induce apoptotic death in melanoma cell lines in culture. Here we report the synthesis of a series of TPMA derivatives, allowing the structure-activity relationship of this class of molecules to be established. Several new compounds have been identified that induce death in UACC-62 and SK-MEL-5 human melanoma cell lines, including a compound with enhanced aqueous solubility.