Next generation of immunotherapy for melanoma

Prediction of immunotherapy responsiveness in melanoma through single-cell sequencing-based characterization of the tumor immune microenvironment

Immune checkpoint inhibitors (ICB) therapy have emerged as effective treatments for melanomas. However, the response of melanoma patients to ICB has been highly heterogenous. Here, by analyzing integrated scRNA-seq datasets from melanoma patients, we revealed significant differences in the TiME composition between ICB-resistant and responsive tissues, with resistant or responsive tissues characterized by an abundance of myeloid cells and CD8+ T cells or CD4+ T cell predominance, respectively. Among CD4+ T cells, CD4+ CXCL13+ Tfh-like cells were associated with an immunosuppressive phenotype linked to immune escape-related genes and negative regulation of T cell activation. We also develop an immunotherapy response prediction model based on the composition of the immune compartment. Our predictive model was validated using CIBERSORTx on bulk RNA-seq datasets from melanoma patients pre- and post-ICB treatment and showed a better performance than other existing models. Our study presents an effective immunotherapy response prediction model with potential for further translation, as well as underscores the critical role of the TiME in influencing the response of melanomas to immunotherapy.

[1,2,4]triazolo[4,3-a]quinoxaline as Novel Scaffold in the Imiqualines Family: Candidates with Cytotoxic Activities on Melanoma Cell Lines

Cutaneous melanoma is one of the most aggressive human cancers and is the deadliest form of skin cancer, essentially due to metastases. Novel therapies are always required, since cutaneous melanoma develop resistance to oncogenic pathway inhibition treatment. The Imiqualine family is composed of heterocycles diversely substituted around imidazo[1,2-a]quinoxaline, imidazo[1,2-a]pyrazine, imidazo[1,5-a]quinoxaline, and pyrazolo[1,5-a]quinoxaline scaffolds, which display interesting activities on a panel of cancer cell lines, especially melanoma cell lines. We have designed and prepared novel compounds based on the [1,2,4]triazolo[4,3-a]quinoxaline scaffold through a common synthetic route, using 1-chloro-2-hydrazinoquinoxaline and an appropriate aldehyde. Cyclization is ensured by an oxidation-reduction mechanism using chloranil. The substituents on positions 1 and 8 were chosen based on previous structure-activity relationship (SAR) studies conducted within our heterocyclic Imiqualine family. Physicochemical parameters of all compounds have also been predicted. A375 melanoma cell line viability has been evaluated for 16 compounds. Among them, three novel [1,2,4]triazolo[4,3-a]quinoxalines display cytotoxic activities. Compounds 16a and 16b demonstrate relative activities in the micromolar range (respectively, 3158 nM and 3527 nM). Compound 17a shows the best EC₅₀ of the novel series (365 nM), even if EAPB02303 remains the lead of the entire Imiqualine family (3 nM).

Low Expression of CLEC2B Indicates Poor Prognosis in Melanoma

Background

Melanoma is a highly malignant skin tumor with a poor prognosis. Identification of novel biomarkers might potentially reveal the underlying mechanisms of melanoma progression.

Methods

We demonstrated the relationship between pan-cancer CLEC2B expression and melanoma samples in The Cancer Genome Atlas (TCGA) database. Next, the Kaplan-Meier plot and Cox regression analysis determined the prognostic value of CLEC2B in melanoma. Biological pathway enrichment was screened by Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and Gene Set Enrichment Analysis (GSEA), enabling the correlation analysis between the immune infiltration level and CLEC2B expression in melanoma. Our final claim was validated using qPCR, immunohistochemistry, Western blot, cell colony formation assays, ethynyldeoxyuridine (Edu) analysis, and cell Invasion assays.

Results

Our study revealed that the high CLEC2B expression correlates with poor overall survival of melanoma patients. Moreover, a low expression of CLEC2B was found in the A375 cell line. In addition, CLEC2B has significant prognostic value in melanoma diagnosis, with an AUC of 0.896. Prognostic analysis showed the low expression of CLEC2B to be independently associated with melanoma patients. Moreover, the expression of CLEC2B was significantly correlated with B cells, eosinophils, macrophages, neutrophils, NK cells, T helper cells, Tregs, Th1 cells, Th17 cells, and Th2 cells. PCR and immunohistochemistry indicated CLEC2B to be significantly downregulated in melanoma. The cell colony formation assay showed CLEC2B knockout increased the proliferation of A375 cells.

Conclusion

Our study established low levels of CLEC2B to be poor prognostic markers, enabling immunosuppressive cell infiltration in melanoma.

Liposomal celecoxib combined with dendritic cell therapy enhances antitumor efficacy in melanoma

Cancer vaccine efficacy is limited by the immunosuppressive nature of the tumor microenvironment created by inflammation, immune inhibitory factors, and regulatory T cells (Tregs). Inspired by the role of cyclooxygenase-2 (COX-2) in inflammation in the tumor site, we proposed that normalization of the tumor microenvironment by celecoxib as a COX-2 inhibitor might improve the efficacy of Dendritic Cell (DC) therapy in a melanoma model. In the present study, liposomal celecoxib (Lip-CLX) was combined with ex vivo generated DC vaccines pulsed with gp100 peptide (in liposomal and non-liposomal forms) for prophylactic and therapeutic evaluation in the B16F10 melanoma model. Tumor site analysis by flow cytometry demonstrated that intravenous administration of Lip-CLX at a dose of 1 mg/kg in four doses effectively normalized the tumor microenvironment by reducing Tregs and IL-10 production. Furthermore, in combination with DC vaccination (DC + Lip-peptide+Lip-CLX), it significantly increased tumor-infiltrating CD4⁺ and CD8⁺ T cells and secretion of IFN-γ. This combinatorial strategy produced an effective prophylactic and therapeutic antitumor response, which reduced tumor growth and prolonged the overall survival. In conclusion, our findings suggest that the liposomal celecoxib targets the inhibitory mechanisms of the tumor microenvironment and broadens the impact of DC therapy to improve the outcome of immunotherapy in solid tumors.

Discovery of Macrocycle-Based HPK1 Inhibitors for T-Cell-Based Immunotherapy

Hematopoietic progenitor kinase 1 (HPK1) is a negative regulator of T-cell activation, and targeting HPK1 is considered a promising strategy for improving responses to antitumor immune therapies. The biggest challenge of HPK1 inhibitor design is to achieve a higher selectivity to GLK, an HPK1 homology protein as a positive regulator of T-cell activation. Herein, we report the design of a series of macrocycle-based HPK1 inhibitors via a conformational constraint strategy. The identified candidate compound 5i exhibited HPK1 inhibition with an IC₅₀ value of 0.8 nM and 101.3-fold selectivity against GLK. Compound 5i also displayed good oral bioavailability (F = 27-49%) in mice and beagles and favorable metabolic stability (T_1/2 > 186.4 min) in human liver microsomes. More importantly, compound 5i demonstrated a clear synergistic effect with anti-PD-1 in both MC38 (MSI) and CT26 (MSS) syngeneic tumor mouse models. These results showed that compound 5i has a great potential in immunotherapy.

p53 mutation and deletion contribute to tumor immune evasion

TP53 (or p53) is widely accepted to be a tumor suppressor. Upon various cellular stresses, p53 mediates cell cycle arrest and apoptosis to maintain genomic stability. p53 is also discovered to suppress tumor growth through regulating metabolism and ferroptosis. However, p53 is always lost or mutated in human and the loss or mutation of p53 is related to a high risk of tumors. Although the link between p53 and cancer has been well established, how the different p53 status of tumor cells help themselves evade immune response remains largely elusive. Understanding the molecular mechanisms of different status of p53 and tumor immune evasion can help optimize the currently used therapies. In this context, we discussed the how the antigen presentation and tumor antigen expression mode altered and described how the tumor cells shape a suppressive tumor immune microenvironment to facilitate its proliferation and metastasis.

Population pharmacokinetic modelling of tremelimumab in patients with advanced solid tumours and the impact of disease status on time-varying clearance

AIMS

Tremelimumab, a cytotoxic T-lymphocyte-associated protein 4 human monoclonal antibody of the immunoglobulin G2 κ isotype, has been studied in oncology clinical trials as both monotherapy and in combination with durvalumab. This study characterized the pharmacokinetics of tremelimumab as monotherapy and in combination with durvalumab and evaluated the impact of patient covariates on pharmacokinetics.

METHODS

A pooled-analysis population pharmacokinetics model was built using NONMEM methodology. Pharmacokinetic data from 5 studies spanning different tumour types and therapy regimens were pooled for model development (956 patients). A dataset pooled from 4 additional studies was used for external validation (554 patients). Demographic and relevant clinical covariates were explored during model development.

RESULTS

Tremelimumab exhibited linear pharmacokinetics, well described by a 2-compartment model, with time-varying clearance (0.276 L/day at baseline) associated primarily with therapy regimen and linked with changes in disease status. As monotherapy and combination therapy, tremelimumab clearance over 1 year increased by ~16% and decreased by ~17%, respectively. Pharmacokinetic behaviour was consistent across patient demographics and cancer subtypes. Patients with higher bodyweight and lower albumin levels at baseline had significantly higher clearance; however, no dosage adjustments are warranted. A flat dose (75 mg) was projected to provide comparable exposure to weight-based dosing (1 mg/kg) in adults.

CONCLUSION

Tremelimumab exhibited linear pharmacokinetics but consistently opposite trends of time-varying clearance as monotherapy and in combination with durvalumab. Baseline bodyweight and albumin were significant covariates, but conversion from weight-based dosing at 1 mg/kg to flat dosing at 75 mg had no clinically relevant impact.

Does Residual Invasive Disease in Wide Local Excision after Diagnosis with Partial Biopsy Technique Influence Survival in Melanoma? Matched-Pair Analysis of Multicenter Selective Lymphadenectomy Trial I and II

BACKGROUND

Current guidelines recommend excisional/complete biopsy for melanoma diagnosis, owing to high rates of residual disease found at wide local excision (WLE) after partial biopsy techniques. We sought to determine any survival disadvantage associated with the presence of residual invasive melanoma in the WLE after diagnosis with a partial biopsy technique.

STUDY DESIGN

Data were examined from Multicenter Selective Lymphadenectomy Trials I and II (MSLT-I and -II), 2 large melanoma trials. Patients diagnosed with excisional/complete biopsy were excluded. Clinicopathologic characteristics, melanoma-specific survival (MSS), distant disease-free survival (DDFS), and disease-free survival (DFS) of those with residual invasive melanoma in the definitive WLE and those with no residual melanoma were compared. Matched pairing was used to reduce variability between groups.

RESULTS

From 1994 through 2014, 3,939 patients were enrolled in these trials and 874 (22%) were diagnosed using partial biopsy techniques. Of these, 399 (46%) had residual tumor in the WLE. Only 6 patients had residual tumor in their WLE resulting in T-upstaging of their tumor. Match-pairing formed two cohorts (1:1) of patients with and without residual invasive tumor after WLE. A total of 514 patients were paired; 288 (56%) males, 148 (28.8%) aged 60 or older, 192 (37.4%) with truncal melanomas, 214 (41.6%) had Breslow thickness 2 mm or greater, and 376 (73.2%) had positive sentinel nodes. Kaplan-Meier analysis showed no statistical difference in 10-year MSS (73.6% ± 3.3% vs 73.9% ± 3.7%, p = 0.891), DDFS (68.7% ± 3.4% vs 65.3% ± 4.0%, p = 0.548), or DFS (59.6% ± 3.7% vs 59.4% ± 3.9%, p = 0.783).

CONCLUSIONS

Survival in patients with primary melanoma does not appear to be worse in patients who undergo a partial biopsy technique and are later found to have residual invasive tumor in the WLE specimen.

Blockade of Myd88 signaling by a novel MyD88 inhibitor prevents colitis-associated colorectal cancer development by impairing myeloid-derived suppressor cells

Background. In cancer, myeloid-derived suppressor cells (MDSCs) are known to escape the host immune system by developing a highly suppressive environment. However, little is known about the molecular mechanism behind MDSC-mediated tumor cell evasion of the immune system. Toll-like receptor (TLR) signaling elicited in the tumor microenvironment has the potential to induce MDSC differentiations in different organs. Therefore, MDSC elimination by blocking the action of myeloid differentiation factor 88 (MyD88), which is a key adaptor-signaling molecule that affects TLR activity, seems to be an ideal tumor immunotherapy. Previous studies have proven that blocking MyD88 signaling with a novel MyD88 inhibitor (TJ-M2010-5, synthesized by Zhou’s group) completely prevented colitis-associated colorectal cancer (CAC) development in mice. Methods. In the present study, we investigated the impact of the novel MyD88 inhibitor on the number, phenotype, and function of MDSC in the mice model of CAC. Results. We showed that CAC growth inhibition was involved in diminished MDSC generation, expansion, and suppressive function and that MDSC-mediated immune escape was dependent on MyD88 signaling pathway activation. MyD88 inhibitor treatment decreased the accumulation of CD11b⁺Gr1⁺ MDSCs in mice with CAC, thereby reducing cytokine (GM-CSF, G-CSF, IL-1β, IL-6 and TGF-β) secretion associated with MDSC accumulation, and reducing the expression of molecules (iNOS, Arg-1 and IDO) associated with the suppressive capacity of MDSCs. In addition, MyD88 inhibitor treatment reduced the differentiation of MDSCs from myeloid cells and the suppressive capacity of MDSCs on the proliferation of activated CD4⁺ T cells in vitro. Conclusion. MDSCs are primary cellular targets of a novel MyD88 inhibitor during CAC development. Our findings prove that MyD88 signaling is involved in the regulation of the immunosuppressive functions of MDSCs. The novel MyD88 inhibitor TJ-M2010-5 is a new and effective agent that modulates MyD88 signaling to overcome MDSC suppressive functions, enabling the development of successful antitumor immunotherapy.

Signal pathways of melanoma and targeted therapy

Melanoma is the most lethal skin cancer that originates from the malignant transformation of melanocytes. Although melanoma has long been regarded as a cancerous malignancy with few therapeutic options, increased biological understanding and unprecedented innovations in therapies targeting mutated driver genes and immune checkpoints have substantially improved the prognosis of patients. However, the low response rate and inevitable occurrence of resistance to currently available targeted therapies have posed the obstacle in the path of melanoma management to obtain further amelioration. Therefore, it is necessary to understand the mechanisms underlying melanoma pathogenesis more comprehensively, which might lead to more substantial progress in therapeutic approaches and expand clinical options for melanoma therapy. In this review, we firstly make a brief introduction to melanoma epidemiology, clinical subtypes, risk factors, and current therapies. Then, the signal pathways orchestrating melanoma pathogenesis, including genetic mutations, key transcriptional regulators, epigenetic dysregulations, metabolic reprogramming, crucial metastasis-related signals, tumor-promoting inflammatory pathways, and pro-angiogenic factors, have been systemically reviewed and discussed. Subsequently, we outline current progresses in therapies targeting mutated driver genes and immune checkpoints, as well as the mechanisms underlying the treatment resistance. Finally, the prospects and challenges in the development of melanoma therapy, especially immunotherapy and related ongoing clinical trials, are summarized and discussed.

Characterization of m6A-Related Genes Landscape in Skin Cutaneous Melanoma to Aid Immunotherapy and Assess Prognosis

Background

Skin cutaneous melanoma (SKCM) is the most malignant tumor among skin cancers. Immunotherapy has shown a great role in the advantageous prognosis of SKCM. However, only a small percentage of people can benefit from immunotherapy. To date, there has been insufficient evidence to reveal the prognostic value of m6A in SKCM and its relationship with the infiltration of immune cells and the efficacy of immunotherapy.

Methods

Here, we synthetically analyzed 23 m6A regulators from SKCM samples collected from the TCGA and GEO databases. We defined three m6A modification patterns and constructed m6A scores using principal component analysis (PCA).

Results

We found significant differences in overall survival (OS) and immune infiltration between different m6A subclusters. Besides, m6A score was positively correlated with regulatory T-cell and helper T-cell content, which may account for the association of high m6A scores with superior prognosis. Multivariate Cox regression analysis revealed that the m6A score was an independent prognostic indicator. Moreover, patients with high m6A scores showed a better response to immunotherapy, and this result was further validated in two independent immunotherapy cohorts receiving anti-PD-1/PD-L1 therapy.

Conclusion

The findings suggested the m6A score can screen suitable candidates for immunotherapy and can predict immunotherapy response. This analysis of different m6A patterns in a large sample of SKCM expanded our understanding of TME and provided new ideas for prognostic assessment and personalized immunotherapy strategies for SKCM patients.

Integrated Analysis of the Transcriptome Profile Reveals the Potential Roles Played by Long Noncoding RNAs in Immunotherapy for Sarcoma

Background

Long-term survival is still low for high-risk patients with soft tissue sarcoma treated with standard management options, including surgery, radiation, and chemotherapy. Immunotherapy is a promising new potential treatment paradigm. However, the application of immune checkpoint inhibitors for the treatment of patients with sarcoma did not yield promising results in a clinical trial. Therefore, there is a considerable need to identify factors that may lead to immune checkpoint inhibitor resistance.

Methods

In this study, we performed a bioinformatic analysis of The Cancer Genome Atlas (TCGA) to detect key long noncoding RNAs (lncRNAs) that were correlated with immune checkpoint inhibitory molecules in sarcoma. The expression levels of these lncRNAs and their correlation with patient prognosis were explored. The upstream long noncoding RNAs were also examined via 450K array data from the TCGA. The potential roles of these lncRNAs were further examined via KEGG and GO analysis using DAVID online software. Finally, the relationship between these lncRNAs and immune cell infiltration in tumors and their effect on immune checkpoint inhibitors were further explored.

Results

We identified lncRNAs correlated with tumor cell immune evasion in sarcoma. The expression of these lncRNAs was upregulated and correlated with worse prognosis in sarcoma and other human cancer types. Moreover, low DNA methylation occupation of these lncRNA loci was detected. Negative correlations between DNA methylation and lncRNA expression were also found in sarcoma and other human cancer types. KEGG and GO analyses indicated that these lncRNAs correlated with immune evasion and negative regulation of the immune response in sarcoma. Finally, high expression of these lncRNAs correlated with more suppressive immune cell infiltration and reduced sensitivity to immune checkpoint inhibitors in sarcoma and other human cancer types.

Conclusion

Our results suggest that long noncoding RNAs confer immune checkpoint inhibitor resistance in human cancer. Further characterization of these lncRNAs may help to elucidate the mechanisms underlying immune checkpoint inhibitor resistance and uncover a novel therapeutic intervention point for immunotherapy.

Immu-Mela: An open resource for exploring immunotherapy-related multidimensional genomic profiles in melanoma

There are increasing studies aimed to reveal genomic hallmarks predictive of immune checkpoint blockade (ICB) treatment response, which generated a large number of data and provided an unprecedented opportunity to identify response-related features and evaluate their robustness across cohorts. However, those valuable data sets are not easily accessible to the research community. To take full advantage of existing large-scale immuno-genomic profiles, we developed Immu-Mela (http://bioinfo.vanderbilt.edu/database/Immu-Mela/), a multidimensional immuno-genomic portal that provides interactive exploration of associations between ICB responsiveness and multi-omics features in melanoma, including genetic, transcriptomics, immune cells, and single-cell populations. Immu-Mela also enables integrative analysis of any two genomic features. We demonstrated the value of Immu-Mela by identifying known and novel genomic features associated with ICB response. In addition, Immu-Mela allows users to upload their data sets (unrestricted to any cancer types) and co-analyze with existing data to identify and validate signatures of interest. Immu-Mela reduces barriers between researchers and complex genomic data, facilitating discoveries in cancer immunotherapy.

Melanoma-infiltrating dendritic cells: Limitations and opportunities of mouse models

The infiltration of melanoma lesions by dendritic cells (DCs) has been suggested to play a tumorigenic role due to the capacity of DCs to induce tumor tolerance and promote angiogenesis as well as metastasis. However, it has also been shown that tumor-infiltrating DCs (TIDCs) induce antitumor responses and hence may be targeted in cost-effective therapeutic approaches to obtain patient-specific DCs that present relevant tumor antigens, without the need for ex vivo DC expansion or tumor antigen identification. Unfortunately, little is known about the composition, nature and function of TIDCs found in human melanoma. The development of mouse melanoma models has greatly contributed to the molecular understanding of melanoma immunology in mice, but many questions on TIDCs remain unanswered. Here, we discuss current knowledge about melanoma TIDCs in various mouse models with regard to their translational potential and clinical relevance.

Imidazo[1,2-a]quinoxalines for melanoma treatment with original mechanism of action

The malignant transformation of melanocytes causes several thousand deaths each year, making melanoma an important public health concern. Melanoma is the most aggressive skin cancer, which incidence has regularly increased over the past decades. We described here the preparation of new compounds based on the 1-(3,4-dihydroxyphenyl)imidazo[1,2-a]quinoxaline structure. Different positions of the quinoxaline moiety were screened to introduce novel substituents in order to study their influence on the biological activity. Several alkylamino or alkyloxy groups were also considered to replace the methylamine of our first generation of Imiqualines. Imidazo[1,2-a]pyrazine derivatives were also designed as potential minimal structure. The investigation on A375 melanoma cells displayed interesting in vitro low nanomolar cytotoxic activity. Among them, 9d (EAPB02303) is particularly remarkable since it is 20 times more potent than vemurafenib, the reference clinical therapy used on BRAF mutant melanoma. Contrary to the first generation, EAPB02303 does not inhibit tubulin polymerization, as confirmed by an in vitro assay and a molecular modelisation study. The mechanism of action for EAPB02303 highlighted by a transcriptomic analysis is clearly different from a panel of 12 well-known anticancer drugs. In vivoEAPB02303 treatment reduced tumor size and weight of the A375 human melanoma xenografts in a dose-dependent manner, correlated with a low mitotic index but not with necrosis.

Programmed death-1 or programmed death ligand-1 inhibitors? A meta-analysis of differential efficacy as compared to chemotherapy in advanced non-small cell lung cancer

BACKGROUND

Programmed Death-1 (PD-1) and Programmed Death Ligand-1 (PDL-1) inhibitors have improved survival over chemotherapy in advanced Non- Small Cell Lung Cancer (NSCLC). However, it is unclear if there are class specific differences in the efficacy of Checkpoint Inhibitors (CPIs) in NSCLC, and this paper is designed to answer these clinical questions.

METHODS

For this Meta-analysis, we searched PubMed, Science of Web, "Clinicaltrials.gov" and online sources for trials comparing PD-1 and PDL-1 CPIs in advanced NSCLC. The data for Hazard Ratio (HR) and their Confidence Intervals (CI) for Overall Survival (OS) was extracted.

RESULTS

A sum of 9739 patients from 16 trials were included in the efficacy evaluation. For the OS endpoint, both PD-1 inhibitors (HR = 0.76, 95%CI = 0.69-0.83, P < 0.001) and PDL-1 inhibitors (HR = 0.84, 95%CI = 0.74-0.95, P < 0.001) were superior to chemotherapy in treatment naïve (upfront) patients, the results were similar in treatment refractory patients (PD-1 inhibitors (HR = 0.67, 95%CI = 0.60-0.75, P < 0.001) and PDL-1 inhibitors (HR = 0.78, 95%CI = 0.69-0.88, P < 0.001) were superior to chemotherapy). There was no difference in the effect of PD-1 and PDL-1 classes of CPIs over chemotherapy in treatment naïve and treatment refractory settings (Q = 1.88, df = 1, P = 0.017, and, Q = 3.27, df = 1, P = 0.070, respectively).

CONCLUSION

Efficacy of PD-1 and PDL-1 class of CPIs was not different, although differences among individual CPIs or their combinations cannot be excluded. We were also able to compute pooled efficacy data, as compared to chemotherapy alone, for trials where these groups of CPIs were utilized.

Adenosine A2A Receptor Antagonists for Cancer Immunotherapy

Currently, the most promising therapeutic modality for cancer treatment is the blockade of immune checkpoint pathways, which has revolutionized cancer therapy in the past 15 years. Strategies targeting and modulating adenosine A_2A receptor (A_2AR), an emerging alternative immune checkpoint, have shown the potential to produce significant therapeutic effects. In this review, we describe the immunosuppressive activities of A_2AR and A_2BR in the tumor microenvironment (TME), followed by a summary and discussion of the structure-activity relationship (SAR) of the A_2AR (and dual A_2AR/A_2BR) antagonists that have been experimentally confirmed to exert oncoimmunological effects. This review also provides an update on the compounds under clinical evaluation and insights into the ligand binding modes of the receptor.

Recent development and applications of nanomaterials for cancer immunotherapy

Immunotherapy, which utilizes the patient’s own immune system to fight against cancer, further results in durable antitumor responses and reduces metastasis and recurrence, has become one of the most effective and important cancer therapies along with surgery, radiotherapy, and chemotherapy. Nanomaterials with the advantages of large specific surface, delivery function, and controllable surface chemistry are used to deliver antigens or adjuvants, or both, help to boost immune responses with the imaging function or just act as adjuvants themselves and modulate tumor microenvironment (TME). In this review, recent development and applications of nanomaterials for cancer immunotherapy including delivery systems based on nanomaterials, uniting imaging, self-adjuvants, targeting functions, artificial antigen presenting cells, and TME modulation are focused and discussed.

Dual Inhibitors-Loaded Nanotherapeutics that Target Kinase Signaling Pathways Synergize with Immune Checkpoint Inhibitor

Introduction

Immune checkpoint inhibitors that boost cytotoxic T cell-based immune responses have emerged as one of the most promising approaches in cancer treatment. However, it is increasingly being realized that T cell activation needs to be rationally combined with molecularly targeted therapeutics for a maximal anti-tumor outcome. Currently, two oncogenic drivers, MAPK and PI3K-mTOR have emerged as the two main molecular targets for combining with immunotherapy. However, there are major challenges in enabling such combinations: first, such combinations can result in high rates of toxicity. Second, while, these molecular targets could be driving tumor progression, they are essential for activation of the immune cells. So, the kinase inhibitors and immunotherapy can antagonize each other.

Objectives

We rationalized that the synergistic combination of kinase inhibitors and immunotherapy could be enabled by dual inhibitors-loaded supramolecular nanotherapeutics (DiLN) that can co-deliver PI3K- and MAPK-inhibitors to the cancer cells and activate immune response by T cell-modulating immunotherapy, resulting in greater anti-tumor efficacy while minimizing toxicity.

Methods

We engineered DiLNs by designing the amphiphilic building blocks (both drugs and co-lipids) that enables supramolecular nanoassembly. DiLNs were tested for their physiochemical properties including size, morphology, stability and drug release kinetics profiles. The efficacy of DiLNs was tested in drug-resistant cells such as BRAF^V600E melanoma (D4M), Clear cell ovarian carcinoma (TOV21G) cells. The tumor inhibition efficiency of DiLNs in combination with immune checkpoint inhibitor antibody was studied in syngeneic D4M animal model.

Results

DiLNs were stable for over a month and released the drugs in a sustained manner. In vitro cytotoxicity studies in D4M and TOV21G cells showed that DiLNs were significantly more effective than free drugs. In vivo studies showed that the combination of DiLNs with anti PD-L1 antibody resulted in superior antitumor effect and survival.

Conclusion

This study shows that the rational combination of DiLNs that target multiple oncogenic signaling pathways with immune checkpoint inhibitors could emerge as an effective strategy to improve immunotherapeutic response against drug resistant tumors.

Systemic treatments for metastatic cutaneous melanoma

BACKGROUND

The prognosis of people with metastatic cutaneous melanoma, a skin cancer, is generally poor. Recently, new classes of drugs (e.g. immune checkpoint inhibitors and small-molecule targeted drugs) have significantly improved patient prognosis, which has drastically changed the landscape of melanoma therapeutic management. This is an update of a Cochrane Review published in 2000.

OBJECTIVES

To assess the beneficial and harmful effects of systemic treatments for metastatic cutaneous melanoma.

SEARCH METHODS

We searched the following databases up to October 2017: the Cochrane Skin Group Specialised Register, CENTRAL, MEDLINE, Embase and LILACS. We also searched five trials registers and the ASCO database in February 2017, and checked the reference lists of included studies for further references to relevant randomised controlled trials (RCTs).

SELECTION CRITERIA

We considered RCTs of systemic therapies for people with unresectable lymph node metastasis and distant metastatic cutaneous melanoma compared to any other treatment. We checked the reference lists of selected articles to identify further references to relevant trials.

DATA COLLECTION AND ANALYSIS

Two review authors extracted data, and a third review author independently verified extracted data. We implemented a network meta-analysis approach to make indirect comparisons and rank treatments according to their effectiveness (as measured by the impact on survival) and harm (as measured by occurrence of high-grade toxicity). The same two review authors independently assessed the risk of bias of eligible studies according to Cochrane standards and assessed evidence quality based on the GRADE criteria.

MAIN RESULTS

We included 122 RCTs (28,561 participants). Of these, 83 RCTs, encompassing 21 different comparisons, were included in meta-analyses. Included participants were men and women with a mean age of 57.5 years who were recruited from hospital settings. Twenty-nine studies included people whose cancer had spread to their brains. Interventions were categorised into five groups: conventional chemotherapy (including single agent and polychemotherapy), biochemotherapy (combining chemotherapy with cytokines such as interleukin-2 and interferon-alpha), immune checkpoint inhibitors (such as anti-CTLA4 and anti-PD1 monoclonal antibodies), small-molecule targeted drugs used for melanomas with specific gene changes (such as BRAF inhibitors and MEK inhibitors), and other agents (such as anti-angiogenic drugs). Most interventions were compared with chemotherapy. In many cases, trials were sponsored by pharmaceutical companies producing the tested drug: this was especially true for new classes of drugs, such as immune checkpoint inhibitors and small-molecule targeted drugs.When compared to single agent chemotherapy, the combination of multiple chemotherapeutic agents (polychemotherapy) did not translate into significantly better survival (overall survival: HR 0.99, 95% CI 0.85 to 1.16, 6 studies, 594 participants; high-quality evidence; progression-free survival: HR 1.07, 95% CI 0.91 to 1.25, 5 studies, 398 participants; high-quality evidence. Those who received combined treatment are probably burdened by higher toxicity rates (RR 1.97, 95% CI 1.44 to 2.71, 3 studies, 390 participants; moderate-quality evidence). (We defined toxicity as the occurrence of grade 3 (G3) or higher adverse events according to the World Health Organization scale.)Compared to chemotherapy, biochemotherapy (chemotherapy combined with both interferon-alpha and interleukin-2) improved progression-free survival (HR 0.90, 95% CI 0.83 to 0.99, 6 studies, 964 participants; high-quality evidence), but did not significantly improve overall survival (HR 0.94, 95% CI 0.84 to 1.06, 7 studies, 1317 participants; high-quality evidence). Biochemotherapy had higher toxicity rates (RR 1.35, 95% CI 1.14 to 1.61, 2 studies, 631 participants; high-quality evidence).With regard to immune checkpoint inhibitors, anti-CTLA4 monoclonal antibodies plus chemotherapy probably increased the chance of progression-free survival compared to chemotherapy alone (HR 0.76, 95% CI 0.63 to 0.92, 1 study, 502 participants; moderate-quality evidence), but may not significantly improve overall survival (HR 0.81, 95% CI 0.65 to 1.01, 2 studies, 1157 participants; low-quality evidence). Compared to chemotherapy alone, anti-CTLA4 monoclonal antibodies is likely to be associated with higher toxicity rates (RR 1.69, 95% CI 1.19 to 2.42, 2 studies, 1142 participants; moderate-quality evidence).Compared to chemotherapy, anti-PD1 monoclonal antibodies (immune checkpoint inhibitors) improved overall survival (HR 0.42, 95% CI 0.37 to 0.48, 1 study, 418 participants; high-quality evidence) and probably improved progression-free survival (HR 0.49, 95% CI 0.39 to 0.61, 2 studies, 957 participants; moderate-quality evidence). Anti-PD1 monoclonal antibodies may also result in less toxicity than chemotherapy (RR 0.55, 95% CI 0.31 to 0.97, 3 studies, 1360 participants; low-quality evidence).Anti-PD1 monoclonal antibodies performed better than anti-CTLA4 monoclonal antibodies in terms of overall survival (HR 0.63, 95% CI 0.60 to 0.66, 1 study, 764 participants; high-quality evidence) and progression-free survival (HR 0.54, 95% CI 0.50 to 0.60, 2 studies, 1465 participants; high-quality evidence). Anti-PD1 monoclonal antibodies may result in better toxicity outcomes than anti-CTLA4 monoclonal antibodies (RR 0.70, 95% CI 0.54 to 0.91, 2 studies, 1465 participants; low-quality evidence).Compared to anti-CTLA4 monoclonal antibodies alone, the combination of anti-CTLA4 plus anti-PD1 monoclonal antibodies was associated with better progression-free survival (HR 0.40, 95% CI 0.35 to 0.46, 2 studies, 738 participants; high-quality evidence). There may be no significant difference in toxicity outcomes (RR 1.57, 95% CI 0.85 to 2.92, 2 studies, 764 participants; low-quality evidence) (no data for overall survival were available).The class of small-molecule targeted drugs, BRAF inhibitors (which are active exclusively against BRAF-mutated melanoma), performed better than chemotherapy in terms of overall survival (HR 0.40, 95% CI 0.28 to 0.57, 2 studies, 925 participants; high-quality evidence) and progression-free survival (HR 0.27, 95% CI 0.21 to 0.34, 2 studies, 925 participants; high-quality evidence), and there may be no significant difference in toxicity (RR 1.27, 95% CI 0.48 to 3.33, 2 studies, 408 participants; low-quality evidence).Compared to chemotherapy, MEK inhibitors (which are active exclusively against BRAF-mutated melanoma) may not significantly improve overall survival (HR 0.85, 95% CI 0.58 to 1.25, 3 studies, 496 participants; low-quality evidence), but they probably lead to better progression-free survival (HR 0.58, 95% CI 0.42 to 0.80, 3 studies, 496 participants; moderate-quality evidence). However, MEK inhibitors probably have higher toxicity rates (RR 1.61, 95% CI 1.08 to 2.41, 1 study, 91 participants; moderate-quality evidence).Compared to BRAF inhibitors, the combination of BRAF plus MEK inhibitors was associated with better overall survival (HR 0.70, 95% CI 0.59 to 0.82, 4 studies, 1784 participants; high-quality evidence). BRAF plus MEK inhibitors was also probably better in terms of progression-free survival (HR 0.56, 95% CI 0.44 to 0.71, 4 studies, 1784 participants; moderate-quality evidence), and there appears likely to be no significant difference in toxicity (RR 1.01, 95% CI 0.85 to 1.20, 4 studies, 1774 participants; moderate-quality evidence).Compared to chemotherapy, the combination of chemotherapy plus anti-angiogenic drugs was probably associated with better overall survival (HR 0.60, 95% CI 0.45 to 0.81; moderate-quality evidence) and progression-free survival (HR 0.69, 95% CI 0.52 to 0.92; moderate-quality evidence). There may be no difference in terms of toxicity (RR 0.68, 95% CI 0.09 to 5.32; low-quality evidence). All results for this comparison were based on 324 participants from 2 studies.Network meta-analysis focused on chemotherapy as the common comparator and currently approved treatments for which high- to moderate-quality evidence of efficacy (as represented by treatment effect on progression-free survival) was available (based on the above results) for: biochemotherapy (with both interferon-alpha and interleukin-2); anti-CTLA4 monoclonal antibodies; anti-PD1 monoclonal antibodies; anti-CTLA4 plus anti-PD1 monoclonal antibodies; BRAF inhibitors; MEK inhibitors, and BRAF plus MEK inhibitors. Analysis (which included 19 RCTs and 7632 participants) generated 21 indirect comparisons.The best evidence (moderate-quality evidence) for progression-free survival was found for the following indirect comparisons:• both combinations of immune checkpoint inhibitors (HR 0.30, 95% CI 0.17 to 0.51) and small-molecule targeted drugs (HR 0.17, 95% CI 0.11 to 0.26) probably improved progression-free survival compared to chemotherapy;• both BRAF inhibitors (HR 0.40, 95% CI 0.23 to 0.68) and combinations of small-molecule targeted drugs (HR 0.22, 95% CI 0.12 to 0.39) were probably associated with better progression-free survival compared to anti-CTLA4 monoclonal antibodies;• biochemotherapy (HR 2.81, 95% CI 1.76 to 4.51) probably lead to worse progression-free survival compared to BRAF inhibitors;• the combination of small-molecule targeted drugs probably improved progression-free survival (HR 0.38, 95% CI 0.21 to 0.68) compared to anti-PD1 monoclonal antibodies;• both biochemotherapy (HR 5.05, 95% CI 3.01 to 8.45) and MEK inhibitors (HR 3.16, 95% CI 1.77 to 5.65) were probably associated with worse progression-free survival compared to the combination of small-molecule targeted drugs; and• biochemotherapy was probably associated with worse progression-free survival (HR 2.81, 95% CI 1.54 to 5.11) compared to the combination of immune checkpoint inhibitors.The best evidence (moderate-quality evidence) for toxicity was found for the following indirect comparisons:• combination of immune checkpoint inhibitors (RR 3.49, 95% CI 2.12 to 5.77) probably increased toxicity compared to chemotherapy;• combination of immune checkpoint inhibitors probably increased toxicity (RR 2.50, 95% CI 1.20 to 5.20) compared to BRAF inhibitors;• the combination of immune checkpoint inhibitors probably increased toxicity (RR 3.83, 95% CI 2.59 to 5.68) compared to anti-PD1 monoclonal antibodies; and• biochemotherapy was probably associated with lower toxicity (RR 0.41, 95% CI 0.24 to 0.71) compared to the combination of immune checkpoint inhibitors.Network meta-analysis-based ranking suggested that the combination of BRAF plus MEK inhibitors is the most effective strategy in terms of progression-free survival, whereas anti-PD1 monoclonal antibodies are associated with the lowest toxicity.Overall, the risk of bias of the included trials can be considered as limited. When considering the 122 trials included in this review and the seven types of bias we assessed, we performed 854 evaluations only seven of which (< 1%) assigned high risk to six trials.

AUTHORS' CONCLUSIONS

We found high-quality evidence that many treatments offer better efficacy than chemotherapy, especially recently implemented treatments, such as small-molecule targeted drugs, which are used to treat melanoma with specific gene mutations. Compared with chemotherapy, biochemotherapy (in this case, chemotherapy combined with both interferon-alpha and interleukin-2) and BRAF inhibitors improved progression-free survival; BRAF inhibitors (for BRAF-mutated melanoma) and anti-PD1 monoclonal antibodies improved overall survival. However, there was no difference between polychemotherapy and monochemotherapy in terms of achieving progression-free survival and overall survival. Biochemotherapy did not significantly improve overall survival and has higher toxicity rates compared with chemotherapy.There was some evidence that combined treatments worked better than single treatments: anti-PD1 monoclonal antibodies, alone or with anti-CTLA4, improved progression-free survival compared with anti-CTLA4 monoclonal antibodies alone. Anti-PD1 monoclonal antibodies performed better than anti-CTLA4 monoclonal antibodies in terms of overall survival, and a combination of BRAF plus MEK inhibitors was associated with better overall survival for BRAF-mutated melanoma, compared to BRAF inhibitors alone.The combination of BRAF plus MEK inhibitors (which can only be administered to people with BRAF-mutated melanoma) appeared to be the most effective treatment (based on results for progression-free survival), whereas anti-PD1 monoclonal antibodies appeared to be the least toxic, and most acceptable, treatment.Evidence quality was reduced due to imprecision, between-study heterogeneity, and substandard reporting of trials. Future research should ensure that those diminishing influences are addressed. Clinical areas of future investigation should include the longer-term effect of new therapeutic agents (i.e. immune checkpoint inhibitors and targeted therapies) on overall survival, as well as the combination of drugs used in melanoma treatment; research should also investigate the potential influence of biomarkers.

Therapeutic Antibodies in Cancer Therapy

The therapeutic arsenal in solid tumors comprises different anticancer strategies with diverse chemotherapeutic agents and a growing number of biological substances. Large clinical study-based chemotherapeutic protocols combined with biologicals have become an important component in (neo-) adjuvant therapy alongside surgery in solid cancers as well as radiation therapy in some instances. In recent years, monoclonal antibodies have entered the mainstream of cancer therapy. Their first use was as antagonists of oncogenic receptor tyrosine kinases, but today monoclonal antibodies have emerged as long-sought vehicles for the targeted delivery of potent chemotherapeutic agents and as powerful tools to manipulate anticancer immune responses. There is a growing number of FDA approved monoclonal antibodies and small molecules targeting specific types of cancer suggestive of the clinical relevance of this approach.Targeted cancer therapies , also referred to as personalized medicine, are being studied for use alone, in combination with other targeted therapies, and in combination with chemotherapy. The use of monoclonal antibodies in colorectal and gastric cancer for example have shown best outcome when combined with chemotherapy, even though single agent anti-EGFR antibodies seem to be active in particular setting of metastatic colorectal cancer patients. However, it is not well defined whether the addition of anti-VEGF - and anti-EGFR strategies to chemotherapy could improve outcome in those patients susceptible to colorectal cancer-related metastases resection. Among the most promising approaches to activating therapeutic antitumor immunity is the blockade of immune checkpoints, exemplified by the recently FDA-approved agent, Ipilimumab, an antibody that blocks the coinhibitory receptor CTLA-4. Capitalizing on the success of Ipilimumab, agents that target a second coinhibitory receptor, PD-1, or its ligand, PD-L1, are in clinical development. This section attempts to discuss recent progress of targeted agents and in tackling a more general target applicable to gastrointestinal cancer .

The importance for immunoregulation for long-term cancer control

Immune checkpoint blockades have recently emerged as a breakthrough treatment for solid tumors showing high response rates and long durability. In melanoma, the combination of ipilimumab with nivolumab showed high efficacy. However, still half the patients do not respond to this treatment. In order to increase the therapeutic ratio in melanoma and other cancers, different approaches are under evaluation. Three relevant questions are at the moment driving the research community: how to maximize benefit while minimizing toxicity; how to better identify patients who are more likely to benefit from immunotherapy; how to convert nonresponders into responders. In this review we summarize the most recent findings and we outline the most likely future challenges.

Immunological Characteristics of Colitis Associated with Anti-CTLA-4 Antibody Therapy

Anti-CTL4-A therapy is associated with development of colitis. We characterized ipilimumab-associated colitis in nine melanoma patients (6 male, mean age: 55.3-yrs). Median value for diarrhea grade was 2, number of ipilimumab doses 2, and interval since last administration 3-wks. Endoscopic characteristics resembled inflammatory bowel disease and histology revealed predominance of plasmacytes or CD4+ T-cells. We observed significant upregulation of Th1 and Th17 effector pathways (>10-fold increase for IFN-γmRNA, >5-fold for IL-17A, p < 0.01 vs. controls). Significant elevation of FoxP3 was also detected. In conclusion, ipilimumab administration results in elevations of effector lymphocytes and pro-inflammatory mediators in the gut lamina propria.

Metastatic Melanoma: Treatment and Survival in the US after the Introduction of Ipilimumab and Vemurafenib

INTRODUCTION

The 5-year survival of metastatic melanoma is < 18%. Historically, treatment options were limited. In 2011, 2 new agents were approved.

METHODS

We re-abstracted the medical records of a random sample (n = 520) of metastatic melanoma patients who had been diagnosed in 2011 and reported to population-based registries in the U.S. We also queried their treating physicians. Factors associated with treatment and survival were assessed using logistic and Cox proportional hazards regressions, respectively.

RESULTS

21.4% of patients received no treatment, 20.8% received ipilimumab and 57.5% of patients with BRAF-positive tumors received vemurafenib/dabrafenib. Receipt of ipilimumab was less likely among patients of 75 years or older (vs. < 55 years: odds ratio (OR) 0.32; 95% confidence interval (CI) 0.15-0.66) and patients without private/military insurance. 46.8% of patients received BRAF testing. Receipt of BRAF testing was less likely among patients of 65 years or more and uninsured patients (OR 0.22; 95% CI 0.07-0.65). Receipt of ipilimumab was associated with better survival during the first 18 months after diagnosis (hazard ratio (HR) 0.66; 95% CI 0.51-0.84) and vemurafenib/dabrafenib with better survival during the first 10 months after diagnosis (HR 0.51; 95% CI 0.36-0.73).

CONCLUSION

The initial dissemination of ipilimumab and vemurafenib/dabrafenib was limited. Additional research is needed to investigate the apparent lack of long-term survival benefit from these agents.

Tumor Immuno-Environment in Cancer Progression and Therapy

The approvals of Provenge (Sipuleucel-T), Ipilimumab (Yervoy/anti-CTLA-4) and blockers of the PD-1 - PD-L1/PD-L2 pathway, such as nivolumab (Opdivo), pembrolizumab (Keytruda), or atezolizumab (Tecentriq), have established immunotherapy as a key component of comprehensive cancer care. Further, murine mechanistic studies and studies in immunocompromised patients have documented the critical role of immunity in effectiveness of radio- and chemotherapy. However, in addition to the ability of the immune system to control cancer progression, it can also promote tumor growth, via regulatory T cells (Tregs), myeloid-derived dendritic cells (MDSCs) and tumor associated macrophages (TAM), which can enhance survival of cancer cells directly or via the regulation of the tumor stroma.An increasing body of evidence supports a central role for the tumor microenvironment (TME) and the interactions between tumor stroma, infiltrating immune cells and cancer cells during the induction and effector phase of anti-cancer immunity, and the overall effectiveness of immunotherapy and other forms of cancer treatment. In this chapter, we discuss the roles of key TME components during tumor progression, metastatic process and cancer therapy-induced tumor regression, as well as opportunities for their modulation to enhance the overall therapeutic benefit.

Nanomaterial-based cancer immunotherapy

This review focuses on summarizing the existing work about nanomaterial-based cancer immunotherapy in detail.

MgAl-layered double hydroxide nanoparticles co-delivering siIDO and Trp2 peptide effectively reduce IDO expression and induce cytotoxic T-lymphocyte responses against melanoma tumor in mice

The co-delivery of Trp2 and siIDO by LDH nanoparticles alleviates immune tolerance and promotes CTL responses in vivo.

Harnessing the Immune System Against Leukemia: Monoclonal Antibodies and Checkpoint Strategies for AML

Acute myeloid leukemia (AML) is the most common leukemia among adults and is associated with a poor prognosis, especially in patients with adverse prognostic factors, older age, or relapsed disease. The last decade has seen a surge in successful immune-based therapies in various solid tumors; however, the role of immune therapies in AML remains poorly defined. This chapter describes the rationale, clinical data, and toxicity profiles of immune-based therapeutic modalities in AML including naked and conjugated monoclonal antibodies, bispecific T-cell engager antibodies, chimeric antigen receptor (CAR)-T cells, and checkpoint blockade via blockade of PD1/PDL1 or CTLA4. Monoclonal antibodies commonly used in AML therapy target highly expressed "leukemia" surface antigens and include (1) naked antibodies against common myeloid markers such as anti-CD33 (e.g., lintuzumab), (2) antibody-drug conjugates linked to either, (a) a highly potent toxin such as calicheamicin, pyrrolobenzodiazepine, maytansine, or others in various anti-CD33 (gemtuzumab ozogamicin, SGN 33A), anti-123 (SL-401), and anti-CD56 (lorvotuzumab mertansine) formulations, or (b) radioactive particles, such as 131I, 213Bi, or 225Ac-labeled anti-CD33 or CD45 antibodies. Novel monoclonal antibodies that recruit and promote proximity-induced cytotoxicity of tumor cells by T cells (bispecific T-cell engager [BiTE] such as anti CD33/CD3, e.g., AMG 330) or block immune checkpoint pathways such as CTLA4 (e.g., ipilimumab) or PD1/PD-L1 (e.g., nivolumab) unleashing the patients T cells to fight leukemic cells are being evaluated in clinical trials in patients with AML. The numerous ongoing clinical trials with immunotherapies in AML will improve our understanding of the biology of AML and allow us to determine the best approaches to immunotherapy in AML.

[Systemic treatment of inoperable metastasized malignant melanoma]

BACKGROUND

The medical therapy of inoperable malignant melanoma has changed dramatically over the last few years.

OBJECTIVES

The purpose of this article is to summarize the current state of systemic medical treatment of malignant melanoma.

MATERIALS AND METHODS

Clinical studies and guidelines in the therapy of malignant melanoma are reviewed.

RESULTS

Medical therapy of inoperable melanoma changed due to developments in immunotherapies (checkpoint inhibitors) and molecular-targeted therapies (BRAF and MEK inhibitors). Checkpoint inhibitors are antibodies administered as infusions every 2-3 weeks, blocking the checkpoints PD-1 or CTLA-4, thus, preventing downregulation of the immune system. BRAF and MEK inhibitors are small molecules, they are given orally and block a certain signaling pathway in tumor cells. The activation of this pathway has to be demonstrated by molecular analysis of tumor tissue first. This strategy is currently registered for 40-50 % of melanomas harboring a BRAF V600 mutation, while the combination of a BRAF plus MEK inhibitor has been proven more efficient than a BRAF inhibitor alone.

DISCUSSION

A fascinating development has started in the melanoma field due to immunotherapeutic and molecular-targeted treatment strategies. The continuation of this development needs further clinical and translational studies. This includes particular clinical studies with the new substances in the adjuvant situation, and sequences and combinations in the metastatic setting. Translational studies are needed to develop biomarkers for response and side effects.

Extensive tumoral melanosis associated with ipilimumab-treated melanoma

Tumoral melanosis describes a pigmented lesion clinically similar to melanoma but on histology reveals dense aggregates of melanin-laden, benign macrophages without malignant cells. In the few reported cases so far, tumoral melanosis has arisen in the skin or lymph node of a patient with a regressed melanoma or an epithelioid tumour. As a marker of regressed primary melanoma, its discovery may prompt investigation and surveillance for undiagnosed local or metastatic disease. Here, we present a unique case of extensive tumoral melanosis arising during ipilimumab treatment of in-transit metastases from a previously excised melanoma.

Anti-CD73 in cancer immunotherapy: awakening new opportunities

In recent years, cancer immunotherapy made significant advances due to a better understanding of the principles underlying tumor biology and immunology. In this context, CD73 is a key molecule, since via degradation of adenosine monophosphate into adenosine, endorses the generation of an immunosuppressed and pro-angiogenic niche within the tumor microenvironment that promotes the onset and progression of cancer. Targeting CD73 results in favorable antitumor effects in pre-clinical models and combined treatments of CD73 blockade with other immune-modulating agents (i.e. anti-CTLA-4 mAb or anti-PD1 mAb) is particularly attractive. Although there is still a long way to go, anti-CD73 therapy, through the development of CD73 monoclonal antibodies, can potentially constitute a new biologic therapy for cancer patients. In this review, we discuss the link between CD73 and the onset, development and spread of tumors, highlighting the potential value of this molecule as a target and as a novel biomarker in the context of personalized cancer therapy.

Targeting Ornithine Decarboxylase by α-Difluoromethylornithine Inhibits Tumor Growth by Impairing Myeloid-Derived Suppressor Cells

α-Difluoromethylornithine (DFMO) is currently used in chemopreventive regimens primarily for its conventional direct anticarcinogenesic activity. However, little is known about the effect of ornithine decarboxylase (ODC) inhibition by DFMO on antitumor immune responses. We showed in this study that pharmacologic blockade of ODC by DFMO inhibited tumor growth in intact immunocompetent mice, but abrogated in the immunodeficient Rag1(-/-) mice, suggesting that antitumor effect of DFMO is dependent on the induction of adaptive antitumor T cell immune responses. Depletion of CD8(+) T cells impeded the tumor-inhibiting advantage of DFMO. Moreover, DFMO treatment enhanced antitumor CD8(+) T cell infiltration and IFN-γ production and augmented the efficacy of adoptive T cell therapy. Importantly, DFMO impaired Gr1(+)CD11b(+) myeloid-derived suppressor cells (MDSCs) suppressive activity through at least two mechanisms, including reducing arginase expression and activity and inhibiting the CD39/CD73-mediated pathway. MDSCs were one primary cellular target of DFMO as indicated by both adoptive transfer and MDSC-depletion analyses. Our findings establish a new role of ODC inhibition by DFMO as a viable and effective immunological adjunct in effective cancer treatment, thereby adding to the growing list of chemoimmunotherapeutic applications of these agents.

Dexamethasone decreases IL-29 expression in house dust mite-stimulated human bronchial epithelial cells

The aim of this study was to explore the effect of IL-29 on the progression of airway allergic disease by detecting the level of IL-29 in airway allergic cell models stimulated by house dust mite (HDM) in the presence or absence of dexamethasone (DEX). The same batch of human bronchial epithelial cells in exponential growth phase was randomly divided into five groups: blank group (A), 300 ng/mL HDM group (B), 1000 ng/mL HDM group (C), 3000 ng/mL HDM group (D), and 300 ng/mL HDM+100 ng/mL DEX group (E). The IL-29 mRNA expression was detected by quantitative reverse transcription polymerase chain reaction (qRT-PCR). The IL-29 protein expression in cell suspension was detected by ELISA. The results showed that after stimulation with HDM for 24 h, the expression of IL-29 was increased significantly, and after co-stimulation with HDM and DEX for 24 h, the expression of IL-29 in group E was significantly lower than that in the groups stimulated by HDM alone but higher than that in the group A. The differences between the different groups were significant (F=132.957, P<0.01). Additionally, the higher the concentration of HDM was, the more significant the increase in the IL-29 expression was. In conclusion, IL-29 may play a role in the progression of airway allergic disease including asthma.

Primer on immuno-oncology and immune response

Advances in the understanding of the immunogenicity of tumors have provided the basis for immuno-oncology, the development of immunotherapeutic agents that augment the patient's antitumor immunity and disrupt the immune-regulatory circuits that allow tumors to evade the immune system. Two immunomodulatory agents recently have been introduced for the treatment of malignancy: sipuleucel-T and ipilimumab. Unlike cytotoxic chemotherapy, immunotherapies stimulate the patient's immune system to mount or augment existing endogenous antitumor immune responses. Both agents have demonstrated significant improvements in long-term overall survival in patients. Like other immunotherapies, sipuleucel-T and ipilimumab also are characterized by adverse events that manifest as immune-related inflammatory conditions that typically are low grade. Management guidelines have been developed and emphasize early recognition of the signs and symptoms of immune-related adverse events and treatment with corticosteroids. Because these events can manifest even after the cessation of therapy, patients treated with immunotherapies should continue to be followed by their oncology team and other healthcare providers.

Safety, correlative markers, and clinical results of adjuvant nivolumab in combination with vaccine in resected high-risk metastatic melanoma

PURPOSE

The anti-programmed death-1 (PD-1) antibody nivolumab (BMS-936558) has clinical activity in patients with metastatic melanoma. Nivolumab plus vaccine was investigated as adjuvant therapy in resected stage IIIC and IV melanoma patients.

EXPERIMENTAL DESIGN

HLA-A*0201 positive patients with HMB-45, NY-ESO-1, and/or MART-1 positive resected tumors received nivolumab (1 mg/kg, 3 mg/kg, or 10 mg/kg i.v.) with a multi-peptide vaccine (gp100, MART-1, and NY-ESO-1 with Montanide ISA 51 VG) every 2 weeks for 12 doses followed by nivolumab maintenance every 12 weeks for 8 doses. Primary objective was safety and determination of a maximum tolerated dose (MTD). Secondary objectives included relapse-free survival (RFS), overall survival (OS), and immunologic correlative studies.

RESULTS

Thirty-three patients were enrolled. Median age was 47 years; 55% were male. Two patients had stage IIIC disease; 31 patients had stage IV disease. Median follow-up was 32.1 months. MTD was not reached. Most common related adverse events (>40%) were vaccine injection site reaction, fatigue, rash, pruritus, nausea, and arthralgias. Five related grade 3 adverse events [hypokalemia (1), rash (1), enteritis (1), and colitis (2)] were observed. Ten of 33 patients relapsed. Estimated median RFS was 47.1 months; median OS was not reached. Increases in CTLA-4(+)/CD4(+), CD25(+)Treg/CD4(+), and tetramer specific CD8(+) T-cell populations were observed with treatment (P < 0.05). Trends for lower baseline myeloid-derived suppressor cell and CD25(+)Treg/CD4(+) populations were seen in nonrelapsing patients; PD-L1 tumor status was not significantly associated with RFS.

CONCLUSIONS

Nivolumab with vaccine is well tolerated as adjuvant therapy and demonstrates immunologic activity with promising survival in high-risk resected melanoma, justifying further study.

Emerging targeted therapies for melanoma treatment (review)

Cutaneous melanoma is an aggressive cancer with a poor prognosis for patients with advanced disease. The identification of several key molecular pathways implicated in the pathogenesis of melanoma has led to the development of novel therapies for this devastating disease. In melanoma, both the Ras/Raf/MEK/ERK (MAPK) and the PI3K/AKT (AKT) signalling pathways are constitutively activated through multiple mechanisms. Targeting various effectors of these pathways with pharmacologic inhibitors may inhibit melanoma cell growth and angiogenesis. Ongoing clinical trials provide hope to improve progression-free survival of patients with advanced melanoma. This review summarizes the most relevant studies focused on the specific action of these new molecular targeted agents. Mechanisms of resistance to therapy are also discussed.

Discovery of N-((4-([1,2,4]triazolo[1,5-a]pyridin-6-yl)-5-(6-methylpyridin-2-yl)-1H-imidazol-2-yl)methyl)-2-fluoroaniline (EW-7197): a highly potent, selective, and orally bioavailable inhibitor of TGF-β type I receptor kinase as cancer immunotherapeutic/antifibrotic agent

A series of 2-substituted-4-([1,2,4]triazolo[1,5-a]pyridin-6-yl)-5-(6-methylpyridin-2-yl)imidazoles was synthesized and evaluated to optimize a prototype inhibitor of TGF-β type I receptor kinase (ALK5), 6. Combination of replacement of a quinoxalin-6-yl moiety of 6 with a [1,2,4]triazolo[1,5-a]pyridin-6-yl moiety, insertion of a methyleneamino linker, and a o-F substituent in the phenyl ring markedly increased ALK5 inhibitory activity, kinase selectivity, and oral bioavailability. The 12b (EW-7197) inhibited ALK5 with IC50 value of 0.013 μM in a kinase assay and with IC50 values of 0.0165 and 0.0121 μM in HaCaT (3TP-luc) stable cells and 4T1 (3TP-luc) stable cells, respectively, in a luciferase assay. Selectivity profiling of 12b using a panel of 320 protein kinases revealed that it is a highly selective ALK5/ALK4 inhibitor. Pharmacokinetic study with 12b·HCl in rats showed an oral bioavailability of 51% with high systemic exposure (AUC) of 1426 ng × h/mL and maximum plasma concentration (Cmax) of 1620 ng/mL. Rational optimization of 6 has led to the identification of a highly potent, selective, and orally bioavailable ALK5 inhibitor 12b.

Emerging options for the treatment of melanoma - focus on ipilimumab

Ipilimumab is a fully human immunoglobulin subclass G1 anticytotoxic-T-lymphocyte-antigen-4 monoclonal antibody. It has been approved by the US Food and Drug Administration (FDA) and the European Medicines Agency for use in advanced melanoma following clear evidence of survival benefit in randomized Phase III studies. It is also under investigation as a treatment for other solid tumors such as renal cell, lung, and prostate cancers. The purported mechanism of antitumor activity of ipilimumab is through T-cell activation, and the side effect profile reflects this. Immune-related adverse events (irAEs) affect 60% of treated patients and 15% are defined as severe. Fortunately, most irAEs are reversible with early diagnosis and correct management. FDA approval of ipilimumab is dependent on the careful execution of a risk evaluation and mitigation strategy, with the aim of increasing awareness amongst patients and clinicians of the immunological risks of treatment, and providing algorithms for management of irAEs as they develop. Ipilimumab is one of the first immunotherapies to become widely available in the setting of solid tumors, and ongoing research aims to elucidate optimal dosing, optimal scheduling, and expanded access to ipilimumab as an adjuvant or maintenance therapy where appropriate. The identification of clinical correlates or biomarkers to identify those likely to benefit from this high-cost therapy is a top priority.

IL-2 therapy promotes suppressive ICOS+ Treg expansion in melanoma patients

High-dose (HD) IL-2 therapy in patients with cancer increases the general population of Tregs, which are positive for CD4, CD25, and the Treg-specific marker Foxp3. It is unknown whether specific subsets of Tregs are activated and expanded during HD IL-2 therapy or whether activation of any particular Treg subset correlates with clinical outcome. Here, we evaluated Treg population subsets that were induced in patients with melanoma following HD IL-2 therapy. We identified a Treg population that was positive for CD4, CD25, Foxp3, and the inducible T cell costimulator (ICOS). This Treg population increased more than any other lymphocyte subset during HD IL-2 therapy and had an activated Treg phenotype, as indicated by high levels of CD39, CD73, and TGF-β. ICOS(+) Tregs were the most proliferative lymphocyte population in the blood after IL-2 therapy. Patients with melanoma with enhanced expansion of ICOS(+) Tregs in blood following the first cycle of HD IL-2 therapy had worse clinical outcomes than patients with fewer ICOS(+) Tregs. However, there was no difference in total Treg expansion between HD IL-2 responders and nonresponders. These data suggest that increased expansion of the ICOS(+) Treg population following the first cycle of HD IL-2 therapy may be predictive of clinical outcome.

Implication of human herpesviruses in oncogenesis through immune evasion and supression

All human herpesviruses (HHVs) have been implicated in immune system evasion and suppression. Moreover, two HHV family members, i.e. EBV and KSHV, are recognised as oncogenic viruses. Our literature review summarises additional examples of possible oncogenic mechanisms that have been attributed to other HHVs. In general, HHVs affect almost every cancer-implicated branch of the immune system, namely tumour-promoting inflammation, immune evasion, and immunosuppression. Some HHVs accomplish these effects by inhibiting apoptotic pathways and by promoting proliferation. Mechanisms related to immunosupression and low grade chronic inflammation could eventually result in the initiation and progression of cancer. In this article we open a discussion on the members of Herpesviridae, their immune evasion and suppression mechanisms, and their possible role in cancer development. We conclude that discerning the mechanisms of interplay between HHV, immune system, and cancer is essential for the development of novel preventative and therapeutic approaches for cancer treatment and prophylaxis.

Immune system functional pathway analysis using single cell network profiling (SCNP): a novel tool in cancer immunotherapy

The development of cancer immunotherapies has been ongoing for many years and has shown limited success. Novel biomarkers are needed to identify patients most likely to respond to anticancer immune-therapeutic approaches. Moreover, a systems-level approach is required for comprehensive understanding of the interconnected components, pathways, and cell types associated with an immune response. In this chapter, we describe single cell network profiling (SCNP), a novel method for assessing and measuring immune function/dysfunction at a systems level. SCNP is a multiparametric flow-cytometry-based analysis that can simultaneously measure, at the single cell level, both extracellular surface markers and changes in intracellular signaling proteins in response to extracellular modulators. Measuring changes in signaling proteins following the application of an external modulation informs on the functional capacity of the signaling network which cannot be assessed by the measurement of basal signaling alone. In addition, the simultaneous analysis of multiple pathways in multiple cell subsets can provide insight into the connectivity of both cell signaling networks and immune cell subtypes. The experimental steps associated with an SCNP assay are (1) pre-analytical sample preparation; (2) modulation for functional analysis; (3) staining with antibody cocktail; (4) data acquisition on flow cytometer; and (5) data analysis and metrics. Important considerations for each step of the assay will be discussed, and data demonstrating the utility of SCNP for immune monitoring applications will be summarized.

Why is melanoma so metastatic?

Malignant melanoma is one of the most aggressive cancers and can disseminate from a relatively small primary tumor and metastasize to multiple sites, including the lung, liver, brain, bone, and lymph nodes. Elucidating the molecular and genetic changes that take place during the metastatic process has led to a better understanding of why melanoma is so metastatic. Herein, we describe the unique features that distinguish melanoma from other solid tumors and contribute to the malignant phenotype of melanoma cells. For example, although melanoma cells are highly antigenic, they are extremely efficient at evading host immune response. Melanoma cells share numerous cell surface molecules with vascular cells, are highly angiogenic, are mesenchymal in nature, and possess a higher degree of 'stemness' than do other solid tumors. Finally, analysis of melanoma mutations has revealed that the gene expression profile of malignant melanoma is different from that of other cancers. Elucidating these molecular and genetic processes in highly metastatic melanoma can lead to the development of improved treatment and individualized therapy options.