Melanoma epidemiology and public health

Vitamin D and Cutaneous Melanoma Risk: An Umbrella Review of Systematic Reviews and Meta-Analyses

Background: Vitamin D (VitD) properties can impact cancer cells. Despite the documented link between VitD levels and prevalence of several cancer types, conflicting findings have been reported for cutaneous melanoma (CM). Objective: This overview aims to compile the evidence from existing systematic reviews and meta-analyses, emphasizing the relationships between VitD serum levels, intake, receptor (VDR) gene polymorphisms, and CM risk. Methods: A literature search in electronic databases was conducted, based on certain inclusion criteria. Results: Twenty-one studies were included. Conflicting evidence between high VitD serum levels, dietary/supplementary intake, and CM risk is highlighted. VDR polymorphisms may play a role in the intricate CM pathogenesis. Also, high serum levels of VitD are associated with improved CM prognosis. Conclusions: This overview showed that the impact of VitD on CM is not clear, and thus further research is suggested to explore its true effect size on CM risk.

The Current Status and Future Direction of Extracellular Nano-vesicles in the Alleviation of Skin Disorders

Exosomes are extracellular vesicles (EVs) that originate from endocytic membranes. The transfer of biomolecules and biological compounds such as enzymes, proteins, RNA, lipids, and cellular waste disposal through exosomes plays an essential function in cell-cell communication and regulation of pathological and physiological processes in skin disease. The skin is one of the vital organs that makes up about 8% of the total body mass. This organ consists of three layers, epidermis, dermis, and hypodermis that cover the outer surface of the body. Heterogeneity and endogeneity of exosomes is an advantage that distinguishes them from nanoparticles and liposomes and leads to their widespread usage in the remedy of dermal diseases. The biocompatible nature of these extracellular vesicles has attracted the attention of many health researchers. In this review article, we will first discuss the biogenesis of exosomes, their contents, separation methods, and the advantages and disadvantages of exosomes. Then we will highlight recent developments related to the therapeutic applications of exosomes in the treatment of common skin disorders like atopic dermatitis, alopecia, epidermolysis bullosa, keloid, melanoma, psoriasis, and systemic sclerosis.

Characterization of Potential Melanoma Predisposition Genes in High-Risk Brazilian Patients

Increased genetic risk for melanoma can occur in the context of germline pathogenic variants in high-penetrance genes, such as CDKN2A and CDK4, risk variants in low- to moderate-penetrance genes (MC1R and MITF), and possibly due to variants in emerging genes, such as ACD, TERF2IP, and TERT. We aimed to identify germline variants in high- and low- to moderate-penetrance melanoma risk genes in Brazilian patients with clinical criteria for familial melanoma syndrome. We selected patients with three or more melanomas or melanoma patients from families with three tumors (melanoma and pancreatic cancer) in first- or second-degree relatives. Genetic testing was performed with a nine-gene panel (ACD, BAP1, CDK4, CDKN2A, POT1, TERT, TERF2IP, MC1R, and MITF). In 36 patients, we identified 2 (5.6%) with germline pathogenic variants in CDKN2A and BAP1 and 4 (11.1%) with variants of uncertain significance in the high-penetrance genes. MC1R variants were found in 86.5%, and both red hair color variants and unknown risk variants were enriched in patients compared to a control group. The low frequency of germline pathogenic variants in the high-penetrance genes and the high prevalence of MC1R variants found in our cohort show the importance of the MC1R genotype in determining the risk of melanoma in the Brazilian melanoma-prone families.

Refactoring and performance analysis of the main CNN architectures: using false negative rate minimization to solve the clinical images melanoma detection problem

BACKGROUND

Melanoma is one of the deadliest tumors in the world. Early detection is critical for first-line therapy in this tumor pathology and it remains challenging due to the need for histological analysis to ensure correctness in diagnosis. Therefore, multiple computer-aided diagnosis (CAD) systems working on melanoma images were proposed to mitigate the need of a biopsy. However, although the high global accuracy is declared in literature results, the CAD systems for the health fields must focus on the lowest false negative rate (FNR) possible to qualify as a diagnosis support system. The final goal must be to avoid classification type 2 errors to prevent life-threatening situations. Another goal could be to create an easy-to-use system for both physicians and patients.

RESULTS

To achieve the minimization of type 2 error, we performed a wide exploratory analysis of the principal convolutional neural network (CNN) architectures published for the multiple image classification problem; we adapted these networks to the melanoma clinical image binary classification problem (MCIBCP). We collected and analyzed performance data to identify the best CNN architecture, in terms of FNR, usable for solving the MCIBCP problem. Then, to provide a starting point for an easy-to-use CAD system, we used a clinical image dataset (MED-NODE) because clinical images are easier to access: they can be taken by a smartphone or other hand-size devices. Despite the lower resolution than dermoscopic images, the results in the literature would suggest that it would be possible to achieve high classification performance by using clinical images. In this work, we used MED-NODE, which consists of 170 clinical images (70 images of melanoma and 100 images of naevi). We optimized the following CNNs for the MCIBCP problem: Alexnet, DenseNet, GoogleNet Inception V3, GoogleNet, MobileNet, ShuffleNet, SqueezeNet, and VGG16.

CONCLUSIONS

The results suggest that a CNN built on the VGG or AlexNet structure can ensure the lowest FNR (0.07) and (0.13), respectively. In both cases, discrete global performance is ensured: 73% (accuracy), 82% (sensitivity) and 59% (specificity) for VGG; 89% (accuracy), 87% (sensitivity) and 90% (specificity) for AlexNet.

Deep learning in computational dermatopathology of melanoma: A technical systematic literature review

Deep learning (DL) has become one of the major approaches in computational dermatopathology, evidenced by a significant increase in this topic in the current literature. We aim to provide a structured and comprehensive overview of peer-reviewed publications on DL applied to dermatopathology focused on melanoma. In comparison to well-published DL methods on non-medical images (e.g., classification on ImageNet), this field of application comprises a specific set of challenges, such as staining artifacts, large gigapixel images, and various magnification levels. Thus, we are particularly interested in the pathology-specific technical state-of-the-art. We also aim to summarize the best performances achieved thus far with respect to accuracy, along with an overview of self-reported limitations. Accordingly, we conducted a systematic literature review of peer-reviewed journal and conference articles published between 2012 and 2022 in the databases ACM Digital Library, Embase, IEEE Xplore, PubMed, and Scopus, expanded by forward and backward searches to identify 495 potentially eligible studies. After screening for relevance and quality, a total of 54 studies were included. We qualitatively summarized and analyzed these studies from technical, problem-oriented, and task-oriented perspectives. Our findings suggest that the technical aspects of DL for histopathology in melanoma can be further improved. The DL methodology was adopted later in this field, and still lacks the wider adoption of DL methods already shown to be effective for other applications. We also discuss upcoming trends toward ImageNet-based feature extraction and larger models. While DL has achieved human-competitive accuracy in routine pathological tasks, its performance on advanced tasks is still inferior to wet-lab testing (for example). Finally, we discuss the challenges impeding the translation of DL methods to clinical practice and provide insight into future research directions.

Pyroptosis-related lncRNA prognostic signatures for cutaneous melanoma and tumor microenvironment status

Aims: To explore whether the expression of pyroptosis-related lncRNAs makes a difference in the prognosis and antitumor immunity of cutaneous melanoma (CM) patients. Methods: A series of analyses were conducted to establish a prognostic risk model and validate its accuracy. Immune-related analyses were performed to further assess the associations among immune status, tumor microenvironment and the prognostic risk model. Results: Eight pyroptosis-related lncRNAs relevant to prognosis were ascertained and applied to establish the prognostic risk model. The low-risk group had a higher overall survival rate. Conclusion: The established prognostic risk model presents better prediction ability for the prognosis of CM patients and provides new possible therapeutic targets for CM.

Melanoma Management: From Epidemiology to Treatment and Latest Advances

Melanoma is the deadliest skin cancer, whose morbidity and mortality indicators show an increasing trend worldwide. In addition to its great heterogeneity, melanoma has a high metastatic potential, resulting in very limited response to therapies currently available, which were restricted to surgery, radiotherapy and chemotherapy for many years. Advances in knowledge about the pathophysiological mechanisms of the disease have allowed the development of new therapeutic classes, such as immune checkpoint and small molecule kinase inhibitors. However, despite the incontestable progress in the quality of life and survival rates of the patients, effectiveness is still far from desired. Some adverse side effects and resistance mechanisms are the main barriers. Thus, the search for better options has resulted in many clinical trials that are now investigating new drugs and/or combinations. The low water solubility of drugs, low stability and rapid metabolism limit the clinical potential and therapeutic use of some compounds. Thus, the research of nanotechnology-based strategies is being explored as the basis for the broad application of different types of nanosystems in the treatment of melanoma. Future development focus on challenges understanding the mechanisms that make these nanosystems more effective.

Analysis of melanoma tumor antigens and immune subtypes for the development of mRNA vaccine

Melanoma has a high degree of malignancy and mortality. While there are some hopeful clinical trials for melanoma treatment in progress, they have not yet to yield significant long-term cure rates. Cancer vaccines including mRNA are currently one of the most promising strategy for tumor immunotherapy. The aim of this study was to analyze the potential tumor antigens in melanoma that could be used to develop mRNA vaccines and identify suitable vaccine populations. The gene expression data and complete clinical information of 471 melanoma samples and 1 normal tissue were retrieved from TCGA. Then, 812 samples of normal skin and their corresponding gene expression data were obtained from GTEx. Overexpressed genes, mutated genes and IRDEGs are used to identify potential tumor antigens. The relationship between the expression level of potential antigen and prognosis was analyzed in GEPIA, and then the immune cell infiltration was estimated based on TIMER algorithm. The expression profiles of IRDEGs were used to identify consensus clusters and immune subtypes of melanoma. Finally, mutational status and immune microenvironment characterization in immune subtypes were analyzed. Five tumor antigens (PTPRC, SIGLEC10, CARD11, LILRB1, ADAMDEC1) were identified as potential tumor antigens according to overexpressed genes, mutated genes and immune-related genes. They were all associated with OS, DFS and APCs. We identified two immune subtypes of melanoma, named IS1 and IS2, which exhibit different clinical features and immune landscapes. Based on the different immune landscape, we may conclude that IS1 is immunophenotypically "cold", while IS2 is "hot". The present research implicates that PTPRC, SIGLEC10, CARD11, LILRB1 and ADAMDEC1 may be the antigenic targets for melanoma mRNA vaccines and IS2 patients may be more effective to these vaccines.

Mapping of MeLiM melanoma combining ICP-MS and MALDI-MSI methods

Here we developed a powerful tool for comprehensive data collection and mapping of molecular and elemental signatures in the Melanoma-bearing Libechov Minipig (MeLiM) model. The combination of different mass spectrometric methods allowed for detail investigation of specific melanoma markers and elements and their spatial distribution in tissue sections. MALDI-MSI combined with HPLC-MS/MS analyses resulted in identification of seven specific proteins, S100A12, CD163, MMP-2, galectin-1, tenascin, resistin and PCNA that were presented in the melanoma signatures. Furthermore, the ICP-MS method allowed for spatial detection of zinc, calcium, copper, and iron elements linked with the allocation of the specific binding proteins.

Epidemiology of Melanoma

Melanoma accounts for 1.7% of global cancer diagnoses and is the fifth most common cancer in the US. Melanoma incidence is rising in developed, predominantly fair-skinned countries, growing over 320% in the US since 1975. However, US mortality has fallen almost 30% over the past decade with the approval of 10 new targeted or immunotherapy agents since 2011. Mutations in the signaling-protein BRAF, present in half of cases, are targeted with oral BRAF/MEK inhibitor combinations, while checkpoint inhibitors are used to restore immunosurveillance likely inactivated by UV radiation. Although the overall 5-year survival has risen to 93.3% in the US, survival for stage IV disease remains only 29.8%. Melanoma is most common in white, older men, with an average age of diagnosis of 65. Outdoor UV exposure without protection is the main risk factor, although indoor tanning beds, immunosuppression, family history and rare congenital diseases, moles, and obesity contribute to the disease. Primary prevention initiatives in Australia implemented since 1988, such as education on sun-protection, have increased sun-screen usage and curbed melanoma incidence, which peaked in Australia in 2005. In the US, melanoma incidence is not projected to peak until 2022-2026. Fewer than 40% of Americans report practicing adequate protection (sun avoidance from 10 a.m.-4 p.m. and regular application of broad-spectrum sunscreen with an SPF > 30). A 2-4-fold return on investment is predicted for a US sun-protection education initiative. Lesion-directed skin screening programs, especially for those at risk, have also cost-efficiently reduced melanoma mortality.

Sendeng-4 Suppressed Melanoma Growth by Induction of Autophagy and Apoptosis

Sendeng-4 is a traditional Chinese medicine that has been successfully applied to anti-inflammatory diseases in clinical practice. Monomers within Sendeng-4 showed promising antitumor activity against lung cancer, colon cancer, and cutaneous cancer. However, potency of Sendeng-4 in melanoma has not been explored. This study aims to explore the potential application of Sendeng-4 in melanoma treatment. In the present study, we systemically investigate the possibility of Sendeng-4 for treatment of melanoma cancer in vitro by proliferation assay, colony formation, flow cell cytometry, RNA-seq, western blot, and fluorescence-based assay. Our data demonstrated that Sendeng-4 suppresses the proliferation and colony formation capacity of melanoma cells and induces cell cycle block at G2/M phase and eventually cell death. Mechanistically, transcriptome sequencing demonstrates that the PI3K-AKT pathway was significantly inactivated upon Sendeng-4 exposure, which was confirmed by western blot showing decreased phosphorylation of AKT. In addition, decreased BCL-2 expression and increased BAX expression were observed, suggesting programmed cell death via apoptosis. Moreover, LC3-II production as well as autophagosomes formation was observed as demonstrated by western blot and immunofluorescence, indicating elevated autophagy network by Sendeng-4 stimulation. Collectively, we concluded that Sendeng-4 might be used as an anticancer drug for melanoma.

Results of a Primary Skin-Cancer-Prevention Campaign in Early Childhood on Sun-Related Knowledge and Attitudes in Southern Hungary

Simple Summary

Primary skin-cancer-prevention campaigns among young children are important as this is the age when individuals are developing behaviors. Our aim was to evaluate sun-protection knowledge and behavior among caregivers in daycare centers and kindergartens and to determine if educational lectures are positively influential. In daycare centers, we discovered that measures of sun protection (e.g., hat, sunscreen, and shaded areas) are more likely to be available when compared to kindergartens. Knowledge regarding sun safety has improved following our initial presentation, however, not significantly. Sun safety policies did not exist in any of the facilities, presenting an urgent need for their implementation.

Abstract

Avoidance of ultraviolet (UV) exposure in early childhood is important for reducing the lifetime risk of developing skin cancer. The goal of the present prospective, multicenter pilot study was to assess the sun-protection practices in kindergartens and daycare centers and to evaluate sun protection knowledge and behavior among caregivers employed in the surveyed facilities. The study consisted of two parts. A baseline questionnaire was completed by the caregivers in relation to knowledge regarding basic sun protection and sun protection practices of the participating facilities. Afterward, a thirty-minute presentation was hosted in reference to this topic. Six months following the presentation, a follow-up questionnaire was distributed among the caregivers, evaluating the attitude-related and behavioral changes towards children. A total of 153 caregivers from five daycare centers (children between 6 months and 3 years of age) and sixteen kindergartens (children between 3 and 7 years of age) willfully participated in our study. According to our results, the main source of information regarding sun protection originated from different types of media. We found that staying in shaded areas and the use of protective clothing were not frequent in the facilities. Following our presentation regarding skin types and sunscreen use, protective measures improved, but not significantly (p = 0.222). The majority (92.31%) of caregivers distributed the information throughout their environment and also to parents. Sun protection knowledge is necessary; however, motivation among caregivers and parents and involvement of children is also relevant. Hence, a continuous, repetitive educational program regarding sun-smart behavior is deemed essential.

The Role of Senescent Cells in Acquired Drug Resistance and Secondary Cancer in BRAFi-Treated Melanoma

Simple Summary

Advances in melanoma treatment include v-Raf murine sarcoma viral oncogene homolog B (BRAF) inhibitors that target the predominant oncogenic mutation found in malignant melanoma. Despite initial success of the BRAF inhibitor (BRAFi) therapies, resistance and secondary cancer often occur. Mechanisms of resistance and secondary cancer rely on upregulation of pro-survival pathways that circumvent senescence. The repeated identification of a cellular senescent phenotype throughout melanoma progression demonstrates the contribution of senescent cells in resistance and secondary cancer development. Incorporating senotherapeutics in melanoma treatment may offer a novel approach for potentially improving clinical outcome.

Abstract

BRAF is the most common gene mutated in malignant melanoma, and predominately it is a missense mutation of codon 600 in the kinase domain. This oncogenic BRAF missense mutation results in constitutive activation of the mitogen-activate protein kinase (MAPK) pro-survival pathway. Several BRAF inhibitors (BRAFi) have been developed to specifically inhibit BRAF^V600 mutations that improve melanoma survival, but resistance and secondary cancer often occur. Causal mechanisms of BRAFi-induced secondary cancer and resistance have been identified through upregulation of MAPK and alternate pro-survival pathways. In addition, overriding of cellular senescence is observed throughout the progression of disease from benign nevi to malignant melanoma. In this review, we discuss melanoma BRAF mutations, the genetic mechanism of BRAFi resistance, and the evidence supporting the role of senescent cells in melanoma disease progression, drug resistance and secondary cancer. We further highlight the potential benefit of targeting senescent cells with senotherapeutics as adjuvant therapy in combating melanoma.

Optical clearing agent increases effectiveness of photodynamic therapy in a mouse model of cutaneous melanoma: an analysis by Raman microspectroscopy

Melanoma is the most aggressive type of skin cancer and a relevant health problem due to its poor treatment response with high morbidity and mortality rates. This study, aimed to investigate the tissue changes of an improved photodynamic therapy (PDT) response when combined with optical clearing agent (OCA) in the treatment of cutaneous melanoma in mice. Photodithazine (PDZ) was administered intraperitoneally and a solution of OCA was topically applied before PDT irradiation. Due to a resultant refractive index matching, OCA-treated tumors are more optically homogenous, improving the PDT response. Raman analysis revealed, when combined with OCA, the PDT response was more homogenous down to 725 µm-depth in thickness.

Reconstruction of lncRNA-miRNA-mRNA network based on competitive endogenous RNA reveals functional lncRNAs in skin cutaneous melanoma

BACKGROUND

Human skin cutaneous melanoma is the most common and dangerous skin tumour, but its pathogenesis is still unclear. Although some progress has been made in genetic research, no molecular indicators related to the treatment and prognosis of melanoma have been found. In various diseases, dysregulation of lncRNA is common, but its role has not been fully elucidated. In recent years, the birth of the "competitive endogenous RNA" theory has promoted our understanding of lncRNAs.

METHODS

To identify the key lncRNAs in melanoma, we reconstructed a global triple network based on the "competitive endogenous RNA" theory. Gene Ontology and KEGG pathway analysis were performed using DAVID (Database for Annotation, Visualization, and Integration Discovery). Our findings were validated through qRT-PCR assays. Moreover, to determine whether the identified hub gene signature is capable of predicting the survival of cutaneous melanoma patients, a multivariate Cox regression model was performed.

RESULTS

According to the "competitive endogenous RNA" theory, 898 differentially expressed mRNAs, 53 differentially expressed lncRNAs and 16 differentially expressed miRNAs were selected to reconstruct the competitive endogenous RNA network. MALAT1, LINC00943, and LINC00261 were selected as hub genes and are responsible for the tumorigenesis and prognosis of cutaneous melanoma.

CONCLUSIONS

MALAT1, LINC00943, and LINC00261 may be closely related to tumorigenesis in cutaneous melanoma. In addition, MALAT1 and LINC00943 may be independent risk factors for the prognosis of patients with this condition and might become predictive molecules for the long-term treatment of melanoma and potential therapeutic targets.

Impact of Sun Exposure and Tanning Patterns on Next-Generation Sequencing Mutations in Melanoma

BACKGROUND

For the past 30 y, the incidence rate of malignant melanoma has risen steadily. Ultraviolet radiation exposure has been identified as the most prevalent modifiable risk factor for melanoma. Here, next-generation sequencing was used to analyze the relationship between multiple sun exposure factors and select cancer-related genes to determine the relationship of sun exposure on the molecular profiles of melanomas.

METHODS

The collection and analysis of study samples were approved by the institutional review board. The patient cohort consisted of 173 patients whose melanoma tissue samples underwent next-generation sequencing analysis for somatic mutations of 50 cancer-related genes. Univariate and multivariate analyses were conducted.

RESULTS

Patients with a history of blistering sunburn had an absolute mutation incidence of 1.67 mutations per patient, compared with patients without a history of blistering sunburn, who had an absolute mutation incidence of 1.16 mutations per patient (P = 0.028). A BRAF mutation was found in more tumors of patients who reported visiting a tanning salon (57.14%), compared with those who had not (18.75%; P = 0.0463). Patients with a previous history of skin cancer were more likely to have a CDKN2A mutation (20.83%), compared with those without a previous history of skin cancer (7.76%; P = 0.0292).

CONCLUSIONS

The trends seen in the molecular profiles of melanomas with respect to various sun exposure factors suggest that sun exposure impacts genetic makeup. Considering the increase in absolute mutation incidence in patients with a history of blistering sunburn suggests that additional genes may contribute to the pathology of malignancy. Future studies will use the unique molecular profiles of melanomas to personalize patient treatments.

A pooled analysis of the prognostic value of PD-L1 in melanoma: evidence from 1062 patients

Background

Programmed death-ligand 1 (PD-L1) was the first identified ligand of programmed death-1 (PD-1). PD-1/PD-L1 interactions inhibit T cell-mediated immune responses, limit cytokine production, and promote tumor immune escape. Recently, many studies have investigated the prognostic value of PD-L1 expression in patients with melanoma. However, the results of these analyses remain a subject of debate. We have therefore carried out a meta-analysis to identify the prognostic role of PD-L1 in melanoma.

Methods

A thorough medical literature search was performed in the databases PubMed, Web of Science, and Embase until October 2019. The pooled hazard ratios (HRs) and 95% confidence intervals (95% CIs) were calculated to evaluate the correlation between PD-L1 overexpression and prognosis. Publication bias was evaluated using Begg’s test and Egger’s test.

Results

Thirteen articles with 1062 enrolled patients were included in this meta-analysis. High PD-L1 expression did not correlate with overall survival (OS) (HR = 0.93, 95% CI 0.57–1.52, P = 0.781) or progression-free survival (PFS) (HR = 0.82, 95% CI 0.43–1.54, P = 0.535). However, PD-L1 overexpression correlated with the absence of lymph node (LN) metastasis (OR = 0.46, 95% CI 0.22–0.95, P = 0.036). Further, there was no significant relationship between PD-L1 expression and sex (OR = 1.29, 95% CI 0.90–1.84, P = 0.159), age (OR = 0.90, 95% CI 0.51–1.57, P = 0.708), or Eastern Cooperative Oncology Group Performance Status (OR = 0.55, 95% CI 0.06–4.83, P = 0.592).

Conclusions

This meta-analysis suggested that PD-L1 expression did not predict an inferior prognosis in patients with melanoma. However, high PD-L1 expression was associated with absence of LN metastasis in such patients.

Kinome Profiling to Predict Sensitivity to MAPK Inhibition in Melanoma and to Provide New Insights into Intrinsic and Acquired Mechanism of Resistance

Mitogen-activated protein kinase (MAPK) inhibition with the combination of BRAF (Rapidly Accelerated Fibrosarcoma) and MEK (Mitogen-activated protein kinase kinase) inhibitors has become the standard of first-line therapy of metastatic melanoma harbouring BRAF V600 mutations. However, about half of the patients present with primary resistance while the remaining develop secondary resistance under prolonged treatment. Thus, there is a need for predictive biomarkers for sensitivity and/or resistance to further refine the patient population likely to benefit from MAPK inhibitors. In this study, we explored a top-down approach using a multiplex kinase assay, first, to discover a kinome signature predicting sensitivity, intrinsic and acquired resistance to MAPK inhibitors in melanoma, and second, to understand the mechanism of resistance using cell lines. Pre-dose tissues from patients (four responders and three non-responders to BRAFi monotherapy) were profiled for phosphotyrosine kinase (PTK) and serine-threonine kinase (STK) activities on a PamChip® peptide microarray in the presence and absence of ex vivo BRAFi. In addition, molecular studies were conducted on four sensitive parental lines, their offspring with acquired resistance to BRAFi and two lines with intrinsic resistance. PTK and STK activities in cell lysates were measured in the presence and absence of ex vivo BRAFi and/or MEKi. In tissue lysates, concentration-dependent ex vivo inhibition of STK and PTK activities with dabrafenib was stronger in responders than in non-responders. This difference was confirmed in cell lines comparing sensitive and resistant ones. Interestingly, common features of resistance were increased activity of receptor tyrosine kinases, Proto-oncogene tyrosine-protein kinase Src (Src) family kinases and protein kinase B (PKB, AKT) signalling. These latter results were confirmed by Western blots. While dabrafenib alone showed an inhibition of STK and PTK activities in both tissues and cell lines, the combination of dabrafenib and trametinib showed an antagonism on the STK activities and a synergism on PTK activities, resulting in stronger inhibitions of overall tyrosine kinase activities. Altogether; these data reveal that resistance of tumours and cell lines to MAPK inhibitors can be predicted using a multiplex kinase assay and is associated with an increase in specific tyrosine kinase activities and globally to AKT signalling in the patient's tissue. Thus, such a predictive kinome signature would help to identify patients with innate resistance to MAPK double inhibition in order to propose other therapies.

Expanding the understanding of the heterogeneous nature of melanoma with bioinformatics and disorder-based proteomics

The past few decades show that incidences of melanoma are on the rise. The risk associated with this disease is an interplay between genetic and host factors and sun exposure. While scientific progress in the treatment of melanoma is remarkable, additional research is needed to improve patient outcomes and to better understand the heterogenous nature of this disease. Fortunately, as the clinical community enters the era of "big data" and personalized medicine, the rise of bioinformatics that stems from recent advances in high throughout profiling of biological information offers potential for innovative treatment options. This study aims to provide an example of the usefulness of bioinformatics and disorder-based proteomics to identify the molecular pathway in melanoma, garner information on selected proteins from this pathway and uncover their intrinsically disordered proteins regions (IDPRs) and investigate functionality implicated in these IDPRs. The present study provides a new look at the melanoma heterogeneity and suggests that, in addition to the well-established genetic heterogeneity of melanoma, there is another level of heterogeneity that lies within the conformational ensembles that stem from intrinsic disorder in melanoma-related proteins. The hope is that these insights will inspire future drug discovery campaigns.

A characterization of sun protection attitudes and behaviors among children and adolescents in the United States

Children and adolescents may be vulnerable to increased ultraviolet radiation exposure and greater risk for subsequent sun-related pathologies. This study examined the demographic, geographic, and phenotypic factors influencing sun exposure and protective behaviors among children and adolescents living in the United States. A cross-sectional survey on perceived sun exposure and protective behaviors was administered at three sports medicine clinics in California, Colorado, and Hawaii. Responses were measured with a 5-item frequency scale: Never, Rarely (25% of the time or less), Sometimes (50% of the time), Often (75% of the time or more), and Always. Sun protective behavior was examined using univariate and multivariate analyses. In total, 860 surveys were collected (52% female, 48% male; mean age 12.7 years). Females reported significantly greater frequency of using sunscreen (p = 0.001), staying in the shade or using an umbrella while in the sun (p = 0.004), and tanning (p < 0.001). Age was inversely associated with sunscreen use frequency (p < 0.001); the percentage of participants who reported always wearing sunscreen decreased as age increased. Participants in Hawaii reported using sunscreen less frequently than those in California and Colorado (p < 0.001). These results identify high-risk populations such as males, older adolescents, and Hawaii's youth who may not be practicing frequent sun protective behaviors. While it is important for youth to stay active, they must also be reminded to adopt protective behaviors while outdoors to prevent unnecessary sun damage and lower the risk of sun exposure complications.

Molecular background of skin melanoma development and progression: therapeutic implications

Melanoma is the most aggressive skin cancer with an increasing number of cases worldwide and curable mostly in its early stage. The improvement in patients' survival in advanced melanoma has been achieved only recently, due to development of new biological drugs for targeted therapies and immunotherapy. Further progress in the treatment of melanoma is clearly dependent on the better understanding of its complex biology. This review describes the most important molecular mechanisms and genetic events underlying skin melanoma development and progression, depicts the way of action of newly developed drugs and indicates new potential therapeutic targets.

Macroenvironment-gene-microenvironment interactions in ultraviolet radiation-induced melanomagenesis

Cutaneous malignant melanoma is one of the few major cancers that continue to exhibit a positive rate of increase in the developed world. A wealth of epidemiological data has undisputedly implicated ultraviolet radiation (UVR) from sunlight and artificial sources as the major risk factor for melanomagenesis. However, the molecular mechanisms of this cause-and-effect relationship remain murky and understudied. Recent efforts on multiple fronts have brought unprecedented expansion of our knowledge base on this subject and it is now clear that melanoma is caused by a complex interaction between genetic predisposition and environmental exposure, primarily to UVR. Here we provide an overview of the effects of the macroenvironment (UVR) on the skin microenvironment and melanocyte-specific intrinsic (mostly genetic) landscape, which conspire to produce one of the deadliest malignancies.

The Clinical Trial Landscape for Melanoma Therapies

(1) Despite many years of research, melanoma still remains a big challenge for modern medicine. The purpose of this article is to review publicly available clinical trials to find trends regarding the number of trials, their location, and interventions including the most frequently studied drugs and their combinations. (2) We surveyed clinical trials registered in the International Clinical Trials Registry Platform (ICTRP), one of the largest databases on clinical trials. The search was performed on 30 November 2018 using the term "melanoma". Data have been supplemented with the information obtained from publicly available data repositories including PubMed, World Health Organization, National Cancer Institute, Centers for Disease Control and Prevention, European Cancer Information System, and many others to bring the historical context of this study. (3) Among the total of 2563 clinical trials included in the analysis, most have been registered in the USA (1487), which is 58% of the total. The most commonly studied drug in clinical trials was ipilimumab, described as applied intervention in 251 trials. (4) An increase in the number of melanoma clinical trials using immunomodulating monoclonal antibody therapies, small molecule-targeted therapies (inhibitors of BRAF, MEK, CDK4/6), and combination therapies is recognized. This illustrates the tendency towards precision medicine.

Melanoma

Cutaneous melanoma causes 55 500 deaths annually. The incidence and mortality rates of the disease differ widely across the globe depending on access to early detection and primary care. Once melanoma has spread, this type of cancer rapidly becomes life-threatening. For more than 40 years, few treatment options were available, and clinical trials during that time were all unsuccessful. Over the past 10 years, increased biological understanding and access to innovative therapeutic substances have transformed advanced melanoma into a new oncological model for treating solid cancers. Treatments that target B-Raf proto-oncogene serine/threonine-kinase (BRAF)V600 (Val600) mutations using selected BRAF inhibitors combined with mitogen-activated protein kinase inhibitors have significantly improved response and overall survival. Furthermore, advanced cutaneous melanoma has developed into a prototype for testing checkpoint-modulating agents, which has increased hope for long-term tumour containment and a potential cure. These expectations have been sustained by clinical success with targeted agents and antibodies that block programmed cell-death protein 1 in locoregional disease, which induces prolongation of relapse-free, distant-metastasis-free, and overall survival times.

Acquired resistance to BRAFi reverses senescence-like phenotype in mutant BRAF melanoma

Targeting MAPK pathway in mutant BRAF melanoma with the specific BRAF inhibitor vemurafenib showed robust initial responses in the majority of patients followed by relapses due to acquired resistance to the drug. In ^V600EBRAF melanoma cell lines, senescence-associated β-galactosidase activity is often encountered in a constitutive manner or induced after MAPK inhibition. However, the link between the senescence-like phenotype and the resistance to BRAF inhibition is not fully understood yet. Our data validate a senescence-like phenotype (low cell proliferation, high cell volume, and high β-Gal activity) in mutant BRAF cells. Vemurafenib increased β-Gal activity in 4 out of 5 sensitive lines and in 2 out of 5 lines with intrinsic resistance to the drug. Interestingly, the 3 lines with acquired resistance to vemurafenib became depending on the drug for proliferation. In absence of drug, these lines showed a lower cell proliferation rate together with a substantial increase of β-Gal activity both in vitro and in vivo. In all settings, the senescence-like phenotype was significantly associated with an inhibition of pRB and cyclin D1, explaining the inhibition of cell proliferation. In conclusion, β-Gal activity is increased by ^V600EBRAF inhibition in the majority of sensitive and intrinsically resistant melanoma cells. Acquired resistance to vemurafenib is associated with a dependence to the drug for cell proliferation and tumor growth, and, in this case, drug removal stimulate β-Gal activity suggesting that the senescence-like phenotype could contribute to the acquired resistance to BRAF inhibition.

Andrographolide inhibits proliferation and induces cell cycle arrest and apoptosis in human melanoma cells

Andrographolide (Andro), a natural compound isolated from Andrographis paniculata, has been demonstrated to have anticancer efficacy in several types of tumors. In the present study, the anticancer effects and mechanism of Andro in human malignant melanoma were investigated. Cell viability analysis was performed using an MTT assay and the effect of Andro on the cell cycle and apoptosis of human malignant melanoma cells was determined by flow cytometry. Western blot analysis was performed to evaluate the protein expression levels of human malignant melanoma cells following treatment with Andro. The results revealed that Andro potently inhibited cell proliferation by inducing G2/M cell-cycle arrest in human malignant melanoma C8161 and A375 cell lines. In addition, treatment with Andro induced apoptosis, which was associated with the cleavage of poly(adenosine diphosphate-ribose) polymerase and activation of caspase-3. It was observed that Andro induced activation of the c-Jun N-terminal kinase and p38 signaling pathway, which may be connected with cell cycle arrest and apoptosis. In conclusion, the results demonstrated that Andro may be a promising and effective agent for antitumor therapy against human malignant melanoma.

Variables that influence BRAF mutation probability: A next-generation sequencing, non-interventional investigation of BRAFV600 mutation status in melanoma

Background

The incidence of melanoma, particularly in older patients, has steadily increased over the past few decades. Activating mutations of BRAF, the majority occurring in BRAFV600, are frequently detected in melanoma; however, the prognostic significance remains unclear. This study aimed to define the probability and distribution of BRAFV600 mutations, and the clinico-pathological factors that may affect BRAF mutation status, in patients with advanced melanoma using next-generation sequencing.

Materials and methods

This was a non-interventional, retrospective study of BRAF mutation testing at two German centers, in Heidelberg and Tübingen. Archival tumor samples from patients with histologically confirmed melanoma (stage IIIB, IIIC, IV) were analyzed using PCR amplification and deep sequencing. Clinical, histological, and mutation data were collected. The statistical influence of patient- and tumor-related characteristics on BRAFV600 mutation status was assessed using multiple logistic regression (MLR) and a prediction profiler.

Results

BRAFV600 mutation status was assessed in 453 samples. Mutations were detected in 57.6% of patients (n = 261), with 48.1% (n = 102) at the Heidelberg site and 66.0% (n = 159) at the Tübingen site. The decreasing influence of increasing age on mutation probability was quantified. A main effects MLR model identified age (p = 0.0001), center (p = 0.0004), and melanoma subtype (p = 0.014) as significantly influencing BRAFV600 mutation probability; ultraviolet (UV) exposure showed a statistical trend (p = 0.1419). An interaction model of age versus other variables showed that center (p<0.0001) and melanoma subtype (p = 0.0038) significantly influenced BRAF mutation probability; age had a statistically significant effect only as part of an interaction with both UV exposure (p = 0.0110) and melanoma subtype (p = 0.0134).

Conclusions

This exploratory study highlights that testing center, melanoma subtype, and age in combination with UV exposure and melanoma subtype significantly influence BRAFV600 mutation probability in patients with melanoma. Further validation of this model, in terms of reproducibility and broader relevance, is required.

Histopathological expression analysis of intercellular adhesion molecule 1 (ICAM-1) along development and progression of human melanoma

Intercellular adhesion molecule 1 (ICAM-1) protein is an important adhesion molecule that facilitates metastasis on one hand, and on the other hand supports the immunological synapse necessary for T-cell mediated elimination. The expression pattern of ICAM-1 in melanoma was studied more than two decades ago, mainly in cell lines or in unmatched melanoma specimens. By using real time PCR we could not demonstrate a clear difference in ICAM-1 mRNA levels between primary melanocytes and primary cultures of metastatic melanoma. However, immunohistochemistry staining of progression tissue microarray comprised of samples of different disease stages derived from different patients, demonstrated a dramatic ICAM-1 upregulation particularly upon the transition from primary tumor to lymph node metastasis. There was no significant difference between lymph node and distant metastases. Importantly, these results were confirmed in an independent tissue microarray comprised of patient-paired specimens from progressive stages of the patient’s disease. These data indicate that ICAM-1 upregulation is required to initiate the lymphatic spread of melanoma (Stage III) but no further increase is associated with progression to remote organs (Stage IV).

Lactoferrin nanoparticle mediated targeted delivery of 5-fluorouracil for enhanced therapeutic efficacy

Malignant melanoma is an aggressive form of skin cancer with high mortality rates. Common treatments for malignant melanoma involve a combination of radiotherapy and chemotherapy with fluorouracil (5-FU). A major challenge with melanoma treatment is active resistance to chemotherapeutic drugs. Superior treatment outcome lies on balance involving optimum therapeutic doses and the side effects associated with dose escalation. The study aimed to efficiently entrap 5-FU in lactoferrin nanoparticles (LfNPs) in an attempt to enhance its therapeutic efficacy. 5-FU loaded lactoferrin nanoparticles (5-FU-LfNPs) were prepared by sol-oil method with a narrow size distribution of 150±20nm 5-FU-LfNPs exhibits high encapsulation efficiency (64±2.3%) and increased storage stability at 4°C. Competitive ligand binding and lysosomal colocalization studies suggested a receptor mediated uptake for LfNPs internalization in B16F10 cells. Moreover, 5-FU-LfNPs show a pH dependent drug release similar to endosomal pH (pH 5 and 6). In addition compared to free 5-FU, 5-FU- LfNPs showed a higher intracellular uptake, prolonged retention and improved cytotoxicity (2.7-fold) in melanoma cells (B16F10). To conclude, LfNPs represent a superior nano-carrier for the targeted delivery of 5-FU in melanoma cells intended for the efficient treatment of melanoma though detailed in vivo investigations are warranted.

A novel immune resistance mechanism of melanoma cells controlled by the ADAR1 enzyme

The blossom of immunotherapy in melanoma highlights the need to delineate mechanisms of immune resistance. Recently, we have demonstrated that the RNA editing protein, adenosine deaminase acting on RNA-1 (ADAR1) is down-regulated during metastatic transition of melanoma, which enhances melanoma cell proliferation and tumorigenicity. Here we investigate the role of ADAR1 in melanoma immune resistance.Importantly, knockdown of ADAR1 in human melanoma cells induces resistance to tumor infiltrating lymphocytes in a cell contact-dependent mechanism. We show that ADAR1, in an editing-independent manner, regulates the biogenesis of miR-222 at the transcription level and thereby Intercellular Adhesion Molecule 1 (ICAM1) expression, which consequently affects melanoma immune resistance. ADAR1 thus has a novel, pivotal, role in cancer immune resistance. Corroborating with these results, the expression of miR-222 in melanoma tissue specimens was significantly higher in patients who had no clinical benefit from treatment with ipilimumab as compared to patients that responded clinically, suggesting that miR-222 could function as a biomarker for the prediction of response to ipilimumab.These results provide not only novel insights on melanoma immune resistance, but also pave the way to the development of innovative personalized tools to enable optimal drug selection and treatment.

UVR exposure and vitamin D in a rural population. A study of outdoor working farmers, their spouses and children

BACKGROUND

Living and working in the countryside may result in excessive UVR exposure, with increased risk of skin cancer. Some sun exposure is, however, recommended, since vitamin D production is UVB-dependent.

OBJECTIVES

To examine UVR exposure and vitamin D levels in a rural population of outdoor working male farmers, their indoor working spouses and their children, expected to receive high UVR exposure.

METHODS

Prospective, cohort study. During the summer 2009 daily, personal UVR exposure and sun behaviour were recorded by dosimetry and diaries (17 403 days). Vitamin D was measured at the end of summer and the following winter.

RESULTS

Risk behaviour (= exposure of shoulders/upper body to the sun), beach days, sunscreen use and sunburns were infrequent. Farmers and boys had the highest daily UVR exposure (both 1.5 SED per day), likewise on work days. On non-work days the UVR exposure was even higher (up to 2.0 SED per day). Farmers, girls and boys had a higher chronic UVR exposure than the spouses, who had more intermittent high UVR exposure. Vitamin D levels did not differ between family members. At the end of summer 16% of the participants were vitamin D insufficient, the following winter, 61%. Some UVR exposure variables correlated positively, but weakly, with vitamin D levels.

CONCLUSIONS

UVR exposure was generally high among this study population, however, vitamin D levels still dropped below the recommended level during winter for most participants. Differences in UVR exposure between the groups did not result in differences in vitamin D levels.

Oncogene-directed small molecule inhibitors for the treatment of cutaneous melanoma

Achievements in cancer genetics and molecular biology have revolutionized the treatment options available for advanced melanoma. Patients with certain molecularly defined melanomas have been the most fortunate beneficiaries of recently US FDA-approved therapies that target aberrant MAPK pathway signaling, yet response rates and duration of response remain suboptimal. Furthermore, many patients harbor melanomas for which no approved targeted therapies currently exist. Since the approval of vemurafenib, a selective BRAF V600E inhibitor, in 2011, there has been a surge of preclinical and clinical studies aimed at developing novel targeted therapies for a wide range of molecularly defined melanomas. In this review, we will examine the present status and future potential of molecularly targeted therapies directed at the most significant oncogenic signaling pathways in melanoma.

Assessment of attitudes towards sun-protective behaviour in Australians: A cross-sectional study

OBJECTIVE

To assess the knowledge, attitudes and behaviour towards sun protection measures in a sample of Australian adults.

METHODS

A multicentre, cross-sectional study was undertaken during 2014 using a population-based survey of 416 individuals over the age of 18. The knowledge, behaviour and attitudes towards sun protection measures in this group of adults were assessed. The impact of educational level and employment status on responses was also evaluated.

RESULTS

Sunscreen is the most common sun-protective measure. Daily sunscreen use is below 20%. Forgetfulness was the largest barrier to sunscreen use. A total of 85% of respondents did not apply a sufficient amount of sunscreen. Only 32% of individuals reapplied sunscreen every 2 hours and 20% never reapplied it. In the preceding year, one or more sun burns were suffered by 46% of the participants in the survey. In all, 36% of individuals rarely or never check their sunscreens expiry date and less than 50% of individuals replaced their sunscreen each year. Furthermore, 65% were unaware that sunscreens stored above 25°C were less effective than when stored correctly as per manufactures labelling.

CONCLUSIONS

This study highlights a number of significant deficiencies that future sun-protection programmes could target in order to improve the general public's knowledge and attitudes towards sun protection. There is also a need for this to be translated into the public's sun-protection behaviour.

Near infrared and skin impedance spectroscopy - a possible support in the diagnostic process of skin tumours in primary health care

BACKGROUND/PURPOSE

The global incidence of skin cancer has increased drastically in recent decades, especially in Australia and Northern Europe. Early detection is crucial for good prognosis and high survival rates. In general, primary care physicians have considerably lower sensitivity and specificity rates for detection of skin cancer, compared to dermatologists. A probable main reason for this is that current diagnostic tools are subjective in nature, and therefore diagnostic skills highly depend on experience. Illustratively, in Sweden, approximately 155 500 benign skin lesions are excised unnecessarily every year. An objective instrument, added to the clinical examination, might improve the diagnostic accuracy, and thus promote earlier detection of malignant skin tumours, as well as reduce medical costs associated with unnecessary biopsies and excisions. The general aim of this study was to investigate the usefulness of the combination of near infrared (NIR) and skin impedance spectroscopy as a supportive tool in the diagnosis and evaluation of skin tumours in primary health care.

METHODS

Near infrared and skin impedance data were collected by performing measurements on suspect malignant, premalignant and benign tumours in the skin of patients seeking primary health care for skin tumour evaluation. The obtained data were analysed using multivariate analysis and compared with the diagnosis received by the conventional diagnostic process.

RESULTS

The observed sensitivity and specificity rates were both 100%, when discriminating malignant and premalignant skin tumours from benign skin tumours, and the observed sensitivity and specificity for separating malignant skin tumours from premalignant and benign skin tumours were also 100%, respectively.

CONCLUSION

The results of this study indicate that the NIR and skin impedance spectroscopy may be a useful supportive tool for the general practitioner in the diagnosis and evaluation of skin tumours in primary health care, as a complement to the visual assessment.

Epidemiological aspects of melanoma at a university hospital dermatology center over a period of 20 years

BACKGROUND

The incidence of melanoma has been steadily rising in past decades. Although it accounts for only 3% of all skin cancers, it is responsible for 75% of deaths.

OBJECTIVE

to describe the epidemiological aspects of melanoma in a university hospital setting over a period of 20 years.

METHODS

A total of 166 patients were analyzed between January 1990 and January 2010 for clinical and histological variables and correlations between them. A 5% level of significance was adopted.

RESULTS

The majority of patients were Caucasians (74%), females (61%), with a mean age at diagnosis of 55. The predominant histological type was lentigo maligna/lentigo maligna melanoma (35.7%) and the head and neck was the most affected site (30.7%). Among non-Caucasians, the acral region was the most affected. Most tumors were in situ (41.1%). Growth of the lesion was the most frequent complaint (58.1%) and bleeding was most frequently associated with melanomas with a depth > 4mm. There were seven deaths (4.2%), with a high risk among men, non-Caucasians and those under 20 years of age, with a Breslow's depth > 2mm, with lentiginous acral melanoma and with a history of growth and bleeding.

CONCLUSIONS

Our sample differs from most of the studies in the predominant location (head and neck), histological type (lentigo maligna/ lentigo maligna melanoma) and a major risk of death under the age of 20, which could be with a reflex of regional variation. Broader studies are necessary for validation of the results.

Platelet-derived growth factor C and calpain-3 are modulators of human melanoma cell invasiveness

The molecular mechanisms responsible for the elevated metastatic potential of malignant melanoma are still not fully understood. In order to shed light on the molecules involved in the acquisition by melanoma of a highly aggressive phenotype, we compared the gene expression profiles of two cell clones derived from the human cutaneous metastatic melanoma cell line M14: a highly invasive clone (M14C2/MK18) and a clone (M14C2/C4) with low ability to invade the extracellular matrix (ECM). The highly invasive phenotype of M14C2/MK18 cells was correlated with overexpression of neuropilin-1, activation of a vascular endothelial growth factor (VEGF)-A/VEGFR-2 autocrine loop and secretion of matrix metalloprotease-2. Moreover, in an in vivo murine model, M14C2/MK18 cells displayed a higher growth rate as compared with M14C2/C4 cells, even though in vitro both clones possessed comparable proliferative potential. Microarray analysis in M14C2/MK18 cells showed a strong upregulation of platelet-derived growth factor (PDGF)-C, a cytokine that contributes to angiogenesis, and downregulation of calpain-3, a calcium-dependent thiol-protease that regulates specific signalling cascade components. Inhibition of PDGF-C with a specific antibody resulted in a significant decrease in ECM invasion by M14C2/MK18 cells, confirming the involvement of PDGF-C in melanoma cell invasiveness. Moreover, the PDGF-C transcript was found to be upregulated in a high percentage of human melanoma cell lines (17/20), whereas only low PDGF-C levels were detected in a few melanocytic cultures (2/6). By contrast, inhibition of calpain-3 activity in M14C2/C4 control cells, using a specific chemical inhibitor, markedly increased ECM invasion, strongly suggesting that downregulation of calpain-3 plays a role in the acquisition of a highly invasive phenotype. The results indicate that PDGF-C upregulation and calpain-3 downregulation are involved in the aggressiveness of malignant melanoma and suggest that modulators of these proteins or their downstream effectors may synergise with VEGF‑A therapies in combating tumour-associated angiogenesis and melanoma spread.

Determinants of inadequate parental sun protection behaviour in their children--results of a cross-sectional study in Germany

OBJECTIVE

Unprotected sun exposure especially during childhood is a risk factor for skin cancer. A combined use of sun protection measures is recommended to protect children. However, the prevalence and determinants for combined use have been scarcely studied in children. The objective of this study was to identify determinants of parental sun protection behaviour.

METHODS

A cross-sectional survey was performed in five regions in Bavaria (Germany) during school entrance health examination (2010/2011). Parents of 4579 children (47% female, aged 5-6 years) completed a self-administered questionnaire (response 61%).

RESULTS

Most children were regularly protected with single measures (shade (69%), clothes (80%), hat (83%), sunscreen (89%), sunglasses (20%)). However, regarding regular and combined use, >50% of children were inadequately protected. Larger family size, lower household equivalent income, darker skin and sunburn history were associated with inadequate use of different sun protection measures. The less frequent use of one sun protection measure was associated with less frequent use of the others. Child's sex, migration background, parental education and sun exposure showed inconsistent results regarding the different sun protection outcomes.

CONCLUSION

Based on our results a regular, combined and correct use of multiple sun protection for children should be promoted independent of sociodemographic characteristics. Priority of shade, clothes and hat before sunscreen should be clarified.

Sequential use of protein kinase inhibitors potentiates their toxicity to melanoma cells: a rationale to combine targeted drugs based on protein expression inhibition profiles

Targeted therapy has shown high efficacy in the treatment of metastatic melanoma with impressive response rates. However, resistance appears after a few months, underlining the need for simultaneous multiple signalling pathway inhibition to provide a durable benefit. The aim of our study was to evaluate the possible synergistic effect of various protein kinase inhibitor combinations targeting SRC, MEK, PI3K or JAK on the survival of representative melanoma cell lines with WTNRAS/WTBRAF and harbouring the most frequent mutations (Q61LNRAS/WTBRAF or WTNRAS/V600EBRAF). By comparing IC50s and protein inhibition profiles, cell exposure to a single inhibitor for 3 days (condition 1) showed that both WTBRAF lines were at least 15-fold more sensitive to SRC inhibition while V600EBRAF cells were 30-fold more sensitive to MEK inhibition, confirming that the latter cells are largely dependent on the MAPK pathway for growth. Concomitant treatment for 3 days (condition 2) revealed an antagonistic effect between SRC and JAK inhibitors as compared to treatment by each inhibitor alone in all 3 lines, supporting that both SRC and JAK stimulate the STAT pathway. Finally, sequential cell exposure to inhibitors by pre-treatment with a single effector at non-toxic but effective on target inhibition concentrations for 7 days followed by the addition of each of the other inhibitors for 3 days (condition 3) showed that MEK, PI3K or JAK inhibitor acted in synergy with the SRC inhibitor in both wild-type and Q61LNRAS cells, suggesting that the first inhibitor could activate the SRC/STAT compensatory signalling pathway. In conclusion, a treatment strategy consisting in a sequential use of targeted inhibitors to first render melanoma cells more dependent on alternative compensatory pathways that should subsequently be inhibited, may enhance efficacy. By contrast, concomitant exposure to various combinations of inhibitors at different concentrations failed to produce such effect, further supporting the importance of both the duration of cell exposure to inhibitors and their sequential use.

Molecular changes induced by the curcumin analogue D6 in human melanoma cells

BACKGROUND

In a previous report, we described the in vitro and in vivo antiproliferative and proapoptotic activity of a hydroxylated biphenyl (D6), a structural analogue of curcumin, on malignant melanoma and neuroblastoma tumours. In this paper, we investigated the molecular changes induced by such a compound, underlying cell growth arrest and apoptosis in melanoma cells.

RESULTS

To shed light on the mechanisms of action of D6, we firstly demonstrated its quick cellular uptake and subsequent block of cell cycle in G2/M phase transition. A gene expression profile analysis of D6-treated melanoma cells and fibroblasts was then carried out on high density microarrays, to assess gene expression changes induced by this compound. The expression profile study evidenced both an induction of stress response pathways and a modulation of cell growth regulation mechanisms. In particular, our data suggest that the antiproliferative and proapoptotic activities of D6 in melanoma could be partially driven by up-regulation of the p53 signalling pathways as well as by down-regulation of the PI3K/Akt and NF-kB pathways. Modulation of gene expression due to D6 treatment was verified by western blot analysis for single proteins of interest, confirming the results from the gene expression profile analysis.

CONCLUSIONS

Our findings contribute to the understanding of the mechanisms of action of D6, through a comprehensive description of the molecular changes induced by this compound at the gene expression level, in agreement with the previously reported anti-tumour effects on melanoma cells.

Tyrosinase-related protein 1 mRNA expression in lymph node metastases predicts overall survival in high-risk melanoma patients

Background:

Clinical outcome of high-risk melanoma patients is not reliably predicted from histopathological analyses of primary tumours and is often adjusted during disease progression. Our study aimed at extending our previous findings in skin metastases to evaluate the prognostic value of tyrosinase-related protein 1 (TYRP1) in lymph node metastases of stages III and IV melanoma patients.

Methods:

TYRP1 mRNA expression in 104 lymph node metastases was quantified by real-time PCR and normalised to S100 calcium-binding protein B (S100B) mRNA expression to correct for tumour load. TYRP1/S100B ratios were calculated and median was used as cutoff value. TYRP1/S100B mRNA values were correlated to clinical follow-up and histopathological characteristics of the primary lesion.

Results:

A high TYRP1/S100B mRNA ratio significantly correlated with reduced disease-free (DFS) and overall survival (OS; Cox regression analysis, P=0.005 and 0.01, respectively), increased Breslow thickness (Spearman's rho test, P<0.001) and the presence of ulceration (Mann–Whitney test, P=0.02) of the primaries. Moreover, high TYRP1/S100B was of better prognostic value (lower P-value) for OS than Breslow thickness and ulceration. Finally, it was well conserved during disease progression with respect to high/low TYRP1 groups.

Conclusion:

High TYRP1/S100B mRNA expression in lymph node metastases from melanoma patients is associated with unfavourable clinical outcome. Its evaluation in lymph node metastases may refine initial prognosis for metastatic patients, may define prognosis for those with unknown or non-evaluable primary lesions and may allow different management of the two groups of patients.

Barriers and facilitators of adherence to medical advice on skin self-examination during melanoma follow-up care

BACKGROUND

Melanoma is the fastest growing tumor of the skin, which disproportionately affects younger and middle-aged adults. As melanomas are visible, recognizable, and highly curable while in early stages, early diagnosis is one of the most effective measures to decrease melanoma-related mortality. Skin self-examination results in earlier detection and removal of the melanoma. Due to the elevated risk of survivors for developing subsequent melanomas, monthly self-exams are strongly recommended as part of follow-up care. Yet, only a minority of high-risk individuals practices systematic and regular self-exams. This can be improved through patient education. However, dermatological education is effective only in about 50% of the cases and little is known about those who do not respond. In the current literature, psychosocial variables like distress, coping with cancer, as well as partner and physician support are widely neglected in relation to the practice of skin self-examination, despite the fact that they have been shown to be essential for other health behaviors and for adherence to medical advice. Moreover, the current body of knowledge is compromised by the inconsistent conceptualization of SSE. The main objective of the current project is to examine psychosocial predictors of skin self-examination using on a rigorous and clinically sound methodology.

METHODS/DESIGN

The longitudinal, mixed-method study examines key psychosocial variables related to the acquisition and to the long-term maintenance of skin self-examination in 200 patients with melanoma. Practice of self-exam behaviors is assessed at 3 and 12 months after receiving an educational intervention designed based on best-practice standards. Examined predictors of skin self-exam behaviors include biological sex, perceived self-exam efficacy, distress, partner and physician support, and coping strategies. Qualitative analyses of semi-structured interviews will complement and enlighten the quantitative findings.

DISCUSSION

The identification of short and long-term predictors of skin self-examination and an increased understanding of barriers will allow health care professionals to better address patient difficulties in adhering to this life-saving health behavior. Furthermore, the findings will enable the development and evaluation of evidence-based, comprehensive intervention strategies. Ultimately, these findings could impact a wide range of outreach programs and secondary prevention initiatives for other populations with increased melanoma risk.

e-Health Tools for Targeting and Improving Melanoma Screening: A Review

The key to improved prognosis for melanoma is early detection and diagnosis, achieved by skin surveillance and secondary prevention (screening). However, adherence to screening guidelines is low, with population-based estimates of approximately 26% for physician-based skin cancer screening and 20–25% for skin self-examination. The recent proliferation of melanoma detection “e-Health” tools, digital resources that facilitate screening in patients often outside of the clinical setting, may offer new strategies to promote adherence and expand the proportion and range of individuals performing skin self-examination. The purpose of this paper is to catalog and categorize melanoma screening e-Health tools to aid in the determination of their efficacy and potential for adoption. The availability and accessibility of such tools, their costs, target audience, and, where possible, information on their efficacy, will be discussed with potential benefits and limitations considered. While e-Health tools targeting melanoma screening are widely available, little has been done to formally evaluate their efficacy and ability to aid in overcoming screening barriers. Future research needs to formally evaluate the potential role of e-Health tools in melanoma prevention.

Spirooxindole derivative SOID-8 induces apoptosis associated with inhibition of JAK2/STAT3 signaling in melanoma cells

Melanoma is generally refractory to current chemotherapy, thus new treatment strategies are needed. In this study, we synthesized a series of spirooxindole derivatives (SOID-1 to SOID-12) and evaluated their antitumor effects on melanoma. Among the 12 spirooxindole derivatives, SOID-8 showed the strongest antitumor activity by viability screening. SOID-8 inhibited viability of A2058, A375, SK-MEL-5 and SK-MEL-28 human melanoma cells in a dose- and time-dependent manner. SOID-8 also induced apoptosis of these tumor cells, which was confirmed by positive Annexin V staining and an increase of poly(ADP-ribose) polymerase cleavage. The antiapoptotic protein Mcl-1, a member of the Bcl-2 family, was downregulated and correlated with SOID-8 induced apoptosis. In addition, SOID-8 reduced tyrosine phosphorylation of Signal Tansducer and Activator of Transcription 3 (STAT3) in both dose- and time-dependent manners. This inhibition was associated with decreased levels of phosphorylation of Janus-activated kinase-2 (JAK2), an upstream kinase that mediates STAT3 phosphorylation at Tyr705. Accordingly, SOID-8 inhibited IL-6-induced activation of STAT3 and JAK2 in melanoma cells. Finally, SOID-8 suppressed melanoma tumor growth in a mouse xenograft model, accompanied with a decrease of phosphorylation of JAK2 and STAT3. Our results indicate that the antitumor activity of SOID-8 is at least partially due to inhibition of JAK2/STAT3 signaling in melanoma cells. These findings suggest that the spirooxindole derivative SOID-8 is a promising lead compound for further development of new preventive and therapeutic agents for melanoma.

Nanobiotechnological Nanocapsules Containing Polyhemoglobin-Tyrosinase: Effects on Murine B16F10 Melanoma Cell Proliferation and Attachment

We have reported previously that daily intravenous infusions of a soluble nanobiotechnological complex, polyhemoglobin-tyrosinase [polyHb-Tyr], can suppress the growth of murine B16F10 melanoma in a mouse model. In order to avoid the need for daily intravenous injections, we have now extended this further as follows. We have prepared two types of biodegradable nanocapsules containing [polyHb-Tyr]. One type is to increase the circulation time and decrease the frequency of injection and is based on polyethyleneglycol-polylactic acid (PEG-PLA) nanocapsules containing [polyHb-Tyr]. The other type is to allow for intratumoural or local injection and is based on polylactic acid (PLA) nanocapsules containing [polyHb-Tyr]. Cell culture studies show that it can inhibit the proliferation of murine B16F10 melanoma cells in the “proliferation model”. It can also inhibit the attachment of murine B16F10 melanoma cells in the “attachment model.” This could be due to the action of tyrosinase on the depletion of tyrosine or the toxic effect of tyrosine metabolites. The other component, polyhemoglobin (polyHb), plays a smaller role in nanocapsules containing [polyHb-Tyr], and this is most likely by its depletion of nitric oxide needed for melanoma cell growth.