Cutaneous Malignant Melanoma: A Review of Early Diagnosis and Management

Cuproptosis in cancers: Function and implications from bench to bedside

Copper, an indispensable micronutrient, is implicated in numerous vital biological processes and is essential for all physiological activities. Recently, the discovery of a novel type of copper-dependent cell death, known as cuproptosis, has shed light on its role in cancer development. Extensive research is currently underway to unravel the mechanisms underlying cuproptosis and its correlation with various cancer types. In this review, we summarize the findings regarding the roles and mechanisms of cuproptosis in various cancer types, including colorectal cancer, lung cancer, gastric cancer, breast cancer, liver cancer and cutaneous melanoma. Furthermore, the effects of copper-related agents such as copper chelators and copper ionophores on cell proliferation, apoptosis, angiogenesis, tumor immunity, and chemotherapy resistance have been explored in cancer preclinical and clinical trials. These insights provide promising avenues for the development of prospective anticancer drugs aimed at inducing cuproptosis.

Regression of metastatic malignant melanoma with dupilumab: A case report

Excoriated pruritus can be an intolerable symptom in patients with cancer where Type 2 inflammation and its associated cytokines IL-4 and IL-13 play major roles in the pruritus. Dupilumab, an antibody blocking IL-4 and IL-13, is approved for treating moderate to severe atopic dermatitis (AD) where itching is a significant symptom. We present a case report of intractable malignancy-associated AD and pruritus with eosinophilia in a patient with stage IV malignant melanoma who was treated with dupilumab. Biweekly treatment with dupilumab led to an immediate improvement in itching and resolution of the AD, which subsided after a few doses and without significant adverse effects. Routine radiologic monitoring of the malignant melanoma showed concomitant resolution of secondary nodules in the lung, liver, and pleura. It was concluded that dupilumab may be a safe and effective treatment for intractable malignancy-associated AD with pruritus and may have potential for moderating metastatic malignant melanoma.

Iris Pigmented Lesions and Risk of Cutaneous Melanoma: Case-Control Study in Lithuania

The global incidence of cutaneous melanoma (CM) is rising, necessitating early detection and identification of risk factors across different populations. A case-control study with 180 patients with primary diagnosed CM and 182 healthy controls was conducted. Participants underwent ophthalmic and skin examinations, where the identification and counting of common melanocytic nevi (CMN) and atypical melanocytic nevi (AMN) was performed. During ophthalmic examination, high-resolution slit lamp iris images were taken. Images were categorized according to iris periphery, collaret, and freckles. There was no difference in iris periphery and collaret color between groups. However, blue/grey iris periphery and blue collaret with or without freckles were the most common patterns. The presence of pigmented iris lesions and 2-5 mm and ≥5 mm in diameter CMNs was strongly associated with CM risk. The evidence from this study indicates that blue or grey periphery and blue collaret iris pattern with iris freckles are 2.74 times higher in the CM group than controls. Further research is needed to explore iris patterns' association with CM risk in diverse populations.

Identification of novel biomarkers in the early diagnosis of malignant melanoma by untargeted liquid chromatography coupled to high-resolution mass spectrometry-based metabolomics: a pilot study

BACKGROUND

Malignant melanoma (MM) is a highly aggressive form of skin cancer whose incidence continues to rise worldwide. If diagnosed at an early stage, it has an excellent prognosis, but mortality increases significantly at advanced stages after distant spread. Unfortunately, early detection of aggressive melanoma remains a challenge.

OBJECTIVES

To identify novel blood-circulating biomarkers that may be useful in the diagnosis of MM to guide patient counselling and appropriate disease management.

METHODS

In this study, 105 serum samples from 26 healthy patients and 79 with MM were analysed using an untargeted approach by liquid chromatography coupled to high-resolution mass spectrometry (LC-HRMS) to compare the metabolomic profiles of both conditions. Resulting data were subjected to both univariate and multivariate statistical analysis to select robust biomarkers. The classification model obtained from this analysis was further validated with an independent cohort of 12 patients with stage I MM.

RESULTS

We successfully identified several lipidic metabolites differentially expressed in patients with stage I MM vs. healthy controls. Three of these metabolites were used to develop a classification model, which exhibited exceptional precision (0.92) and accuracy (0.94) when validated on an independent sample.

CONCLUSIONS

These results demonstrate that metabolomics using LC-HRMS is a powerful tool to identify and quantify metabolites in bodily fluids that could serve as potential early diagnostic markers for MM.

An efficient multi-class classification of skin cancer using optimized vision transformer

Skin cancer is a pervasive and deadly disease, prompting a surge in research efforts towards utilizing computer-based techniques to analyze skin lesion images to identify malignancies. This paper introduces an optimized vision transformer approach for effectively classifying skin tumors. The methodology begins with a pre-processing step aimed at preserving color constancy, eliminating hair artifacts, and reducing image noise. Here, a combination of techniques such as piecewise linear bottom hat filtering, adaptive median filtering, Gaussian filtering, and an enhanced gradient intensity method is used for pre-processing. Afterwards, the segmentation phase is initiated using the self-sparse watershed algorithm on the pre-processed image. Subsequently, the segmented image is passed through a feature extraction stage where the hybrid Walsh-Hadamard Karhunen-Loeve expansion technique is employed. The final step involves the application of an improved vision transformer for skin cancer classification. The entire methodology is implemented using the Python programming language, and the International Skin Imaging Collaboration (ISIC) 2019 database is utilized for experimentation. The experimental results demonstrate remarkable performance with the different performance metrics is accuracy 99.81%, precision 96.65%, sensitivity 98.21%, F-measure 97.42%, specificity 99.88%, recall 98.21%, Jaccard coefficient 98.54%, and Mathew's correlation coefficient (MCC) 98.89%. The proposed methodology outperforms the existing methodology.

Circulating miRNAs as biomarkers for the diagnosis in patients with melanoma: systematic review and meta-analysis

Objective: Melanoma is the most aggressive and deadly form of skin cancer, especially at later stages. There is currently no excellent diagnostic test established for the diagnosis of melanoma; however, circulating microRNAs (miRNAs) have shown some promise. We seek to conduct a systematic review and meta-analysis to establish the clinical utility of circulating miRNAs in diagnosing melanoma. Methods: PubMed, Wiley, and Web of Science were searched for studies that determined miRNA sensitivity and specificity in patients with melanoma. The included studies were assessed in Stata, and the sensitivity, specificity, summary receiver operating characteristic (SROC), positive likelihood ratio, negative likelihood ratio, and the area under the SROC curve (AUC) were calculated. Results: 9 studies with 898 melanoma patients were included in the meta-analysis. The circulating miRNAs showed high diagnostic accuracy with a sensitivity of 0.89 (p < 0.001), specificity of 0.85 (p < 0.001), diagnostic odds ratio of 45, and an area under the curve of 0.93. Conclusion: Circulating miRNAs have shown a high diagnostic power in detecting melanoma.

Aggregation-induced signal amplification strategy based on peptide self-assembly for ultrasensitive electrochemical detection of melanoma biomarker

The detection of melanoma circulating biomarker in liquid biopsies is current under evaluation for being potentially utilized for earlier cancer diagnosis and its metastasis. Herein, we developed a non-invasive electrochemical approach for ultrasensitive detection of the S100B, serving as a potential promising blood circulating biomarker of melanoma, based on an aggregation-induced signal amplification (AISA) strategy via in-situ peptide self-assembly. The fundamental principle of this assay is that the designed amphiphilic peptides (C16-Pep-Fc), fulfilling multiple functions, feature both a recognition region for specific binding to S100B and an aggregation (self-assembly) region for the formation of peptide nanomicelles under mild conditions. The C16 tails were encapsulated within the hydrophobic core of the aggregates, while the relatively hydrophilic recognition fragment Pep and Fc tag were exposed on the outer surface for subsequent recognition of S100B and signal output. AISA provided remarkable accumulation of electroactive Fc moieties that enabled ultrasensitive S100B detection of as low as 0.02 nM, which was 10-fold lower than un-amplified approach and better than previously reported assays. As a proof-of-concept study, further experiments also highlighted the good reproducibility and stability of AISA and demonstrated its usability when applied to simulated serum samples. Hence, this work not only presented a valuable assay tool for ultrasensitive detecting protein biomarker, but also advocated for the utilization of aggregation-induced signal amplification in electrochemical biosensing system, given its considerable potential for future practical applications.

A Narrative Review of Current Knowledge on Cutaneous Melanoma

Cutaneous melanoma is a public health problem. Efforts to reduce its incidence have failed, as it continues to increase. In recent years, many risk factors have been identified. Numerous diagnostic systems exist that greatly assist in early clinical diagnosis. The histopathological aspect illustrates the grim nature of these cancers. Currently, pathogenic pathways and the tumor microclimate are key to the development of therapeutic methods. Revolutionary therapies like targeted therapy and immune checkpoint inhibitors are starting to replace traditional therapeutic methods. Targeted therapy aims at a specific molecule in the pathogenic chain to block it, stopping cell growth and dissemination. The main function of immune checkpoint inhibitors is to boost cellular immunity in order to combat cancer cells. Unfortunately, these therapies have different rates of effectiveness and side effects, and cannot be applied to all patients. These shortcomings are the basis of increased incidence and mortality rates. This study covers all stages of the evolutionary sequence of melanoma. With all these data in front of us, we see the need for new research efforts directed at therapies that will bring greater benefits in terms of patient survival and prognosis, with fewer adverse effects.

Emerging role of microRNAs as regulators of protein kinase C substrate MARCKS and MARCKSL1 in cancer

MicroRNAs (miRNAs) have emerged as pivotal regulators of gene expression, playing essential roles in diverse cellular processes, including the development and progression of cancer. Among the numerous proteins influenced by miRNAs, the MARCKS/MARCKSL1 protein, a key regulator of cellular cytoskeletal dynamics and membrane-cytosol communication, has garnered significant attention due to its multifaceted involvement in various cancer-related processes, including cell migration, invasion, metastasis, and drug resistance. Motivated by the encouraging early clinical success of peptides targeting MARCKS in several pathological conditions, this review article delves into the intricate interplay between miRNAs and the MARCKS protein in cancer. Herein, we have highlighted the latest findings on specific miRNAs that modulate MARCKS/MARCKSL1 expression, providing a comprehensive overview of their roles in different cancer types. We have underscored the need for in-depth investigations into the therapeutic feasibility of targeting the miRNA-MARCKS axis in cancer, taking cues from the successes witnessed in related fields. Unlocking the full potential of miRNA-mediated MARCKS regulation could pave the way for innovative and effective therapeutic interventions against various cancer types.

Optimizing Skin Cancer Survival Prediction with Ensemble Techniques

The advancement in cancer research using high throughput technology and artificial intelligence (AI) is gaining momentum to improve disease diagnosis and targeted therapy. However, the complex and imbalanced data with high dimensionality pose significant challenges for computational approaches and multi-omics data analysis. This study focuses on predicting skin cancer and analyzing overall survival probability. We employ the Kaplan-Meier estimator and Cox proportional hazards regression model, utilizing high-throughput machine learning (ML)-based ensemble methods. Our proposed ML-based ensemble techniques are applied to a publicly available dataset from the ICGC Data Portal, specifically targeting skin cutaneous melanoma cancers (SKCM). We used eight baseline classifiers, namely, random forest (RF), decision tree (DT), gradient boosting (GB), AdaBoost, Gaussian naïve Bayes (GNB), extra tree (ET), logistic regression (LR), and light gradient boosting machine (Light GBM or LGBM). The study evaluated the performance of the proposed ensemble methods and survival analysis on SKCM. The proposed methods demonstrated promising results, outperforming other algorithms and models in terms of accuracy compared to traditional methods. Specifically, the RF classifier exhibited outstanding precision results. Additionally, four different ensemble methods (stacking, bagging, boosting, and voting) were created and trained to achieve optimal results. The performance was evaluated and interpreted using accuracy, precision, recall, F1 score, confusion matrix, and ROC curves, where the voting method achieved a promising accuracy of 99%. On the other hand, the RF classifier achieved an outstanding accuracy of 99%, which exhibits the best performance. We compared our proposed study with the existing state-of-the-art techniques and found significant improvements in several key aspects. Our approach not only demonstrated superior performance in terms of accuracy but also showcased remarkable efficiency. Thus, this research work contributes to diagnosing SKCM with high accuracy.

Identification and targeting of cancer-associated fibroblast signature genes for prognosis and therapy in Cutaneous melanoma

BACKGROUND

Cancer-associated fibroblasts (CAFs) play pivotal roles in tumor invasion and metastasis. However, studies on CAF biomarkers in Cutaneous Melanoma (CM) are still scarce. This study aimed to explore the potential CAF biomarkers in CM, propose the potential therapeutic targets, and provide new insights for targeted therapy of CAFs in CM.

METHODS

We utilized weighted gene co-expression network analysis to identify CAF signature genes in CM, and conducted comprehensive bioinformatics analysis on the CAF risk score established by these genes. Moreover, single-cell sequencing analysis, spatial transcriptome analysis, and cell experiments were utilized for verifying the expression and distribution pattern of signature genes. Furthermore, molecular docking was employed to screen potential target drugs.

RESULTS

FBLN1 and COL5A1, two crucial CAF signature genes, were screened to establish the CAF risk score. Subsequently, a comprehensive bioinformatic analysis of the CAF risk score revealed that high-risk score group was significantly enriched in pathways associated with tumor progression. Besides, CAF risk score was significantly negatively correlated with clinical prognosis, immunotherapy response, and tumor mutational burden in CM patients. In addition, FBLN1 and COL5A1 were further identified as CAF-specific biomarkers in CM by multi-omics analysis and experimental validation. Eventually, based on these two targets, Mifepristone and Dexamethasone were screened as potential anti-CAFs drugs.

CONCLUSION

The findings indicated that FBLN1 and COL5A1 were the CAF signature genes in CM, which were associated with the progression, treatment, and prognosis of CM. The comprehensive exploration of CAF signature genes is expected to provide new insight for clinical CM therapy.

Exploring the Complex and Multifaceted Interplay between Melanoma Cells and the Tumor Microenvironment

Malignant melanoma is a very aggressive skin cancer, characterized by a heterogeneous nature and high metastatic potential. The incidence of melanoma is continuously increasing worldwide, and it is one of the most common cancers in young adults. In the past twenty years, our understanding of melanoma biology has increased profoundly, and disease management for patients with disseminated disease has improved due to the emergence of immunotherapy and targeted therapy. However, a significant fraction of patients relapse or do not respond adequately to treatment. This can partly be explained by the complex signaling between the tumor and its microenvironment, giving rise to melanoma phenotypes with different patterns of disease progression. This review focuses on the key aspects and complex relationship between pathogenesis, genetic abnormalities, tumor microenvironment, cellular plasticity, and metabolic reprogramming in melanoma. By acquiring a deeper understanding of the multifaceted features of melanomagenesis, we can reach a point of more individualized and patient-centered disease management and reduced costs of ineffective treatments.

Learning how to detect: A deep reinforcement learning method for whole-slide melanoma histopathology images

Cutaneous melanoma represents one of the most life-threatening malignancies. Histopathological image analysis serves as a vital tool for early melanoma detection. Deep neural network (DNN) models are frequently employed to aid pathologists in enhancing the efficiency and accuracy of diagnoses. However, due to the paucity of well-annotated, high-resolution, whole-slide histopathology image (WSI) datasets, WSIs are typically fragmented into numerous patches during the model training and testing stages. This process disregards the inherent interconnectedness among patches, potentially impeding the models' performance. Additionally, the presence of excess, non-contributing patches extends processing times and introduces substantial computational burdens. To mitigate these issues, we draw inspiration from the clinical decision-making processes of dermatopathologists to propose an innovative, weakly supervised deep reinforcement learning framework, titled Fast medical decision-making in melanoma histopathology images (FastMDP-RL). This framework expedites model inference by reducing the number of irrelevant patches identified within WSIs. FastMDP-RL integrates two DNN-based agents: the search agent (SeAgent) and the decision agent (DeAgent). The SeAgent initiates actions, steered by the image features observed in the current viewing field at various magnifications. Simultaneously, the DeAgent provides labeling probabilities for each patch. We utilize multi-instance learning (MIL) to construct a teacher-guided model (MILTG), serving a dual purpose: rewarding the SeAgent and guiding the DeAgent. Our evaluations were conducted using two melanoma datasets: the publicly accessible TCIA-CM dataset and the proprietary MELSC dataset. Our experimental findings affirm FastMDP-RL's ability to expedite inference and accurately predict WSIs, even in the absence of pixel-level annotations. Moreover, our research investigates the WSI-based interactive environment, encompassing the design of agents, state and reward functions, and feature extractors suitable for melanoma tissue images. This investigation offers valuable insights and references for researchers engaged in related studies. The code is available at: https://github.com/titizheng/FastMDP-RL.

TP53 and its Regulatory Genes as Prognosis of Cutaneous Melanoma

The present study was the first comprehensive investigation of genetic mutation and expression levels of the p53 signaling genes in cutaneous melanoma through various genetic databases providing large datasets. The mutational landscape of p53 and its signaling genes was higher than expected, with TP53 followed by CDKN2A being the most mutated gene in cutaneous melanoma. Furthermore, the expression analysis showed that TP53, MDM2, CDKN2A, and TP53BP1 were overexpressed, while MDM4 and CDKN2B were under-expressed in cutaneous melanoma. Overall, TCGA data revealed that among all the other p53 signaling proteins, CDKN2A was significantly higher in both sun and non-sun-exposed healthy tissues than in melanoma. Likewise, MDM4 and TP53BP1 expressions were markedly greater in non-sun-exposed healthy tissues compared to other groups. However, CDKN2B expression was higher in the sun-exposed healthy tissues than in other tissues. In addition, various genes were expressed significantly differently among males and females. In addition, CDKN2A was highly expressed in the SK-MEL-30 skin cancer cell line, whereas, Immune cell type expression analysis revealed that the MDM4 was highly expressed in naïve B-cells. Furthermore, all six genes were significantly overexpressed in extraordinarily overweight or obese tumor tissues compared to healthy tissues. MDM2 expression and tumor stage were closely related. There were differences in gene expression across patient age groups and positive nodal status. TP53 showed a positive correlation with B cells, MDM2 with CD8+T cells, macrophages and neutrophils, and MDM4 with neutrophils. CDKN2A/B had a non-significant correlation with all six types of immune cells. However, TP53BP1 was positively correlated with all five types of immune cells except B cells. Only TP53, MDM2, and CDKN2A had a role in cutaneous melanoma-specific tumor immunity. All TP53 and its regulating genes may be predictive for prognosis. The results of the present study need to be validated through future screening, in vivo, and in vitro studies.

Structural Characterization and Anticancer Activity of a New Anthraquinone from Senna velutina (Fabaceae)

In this study, a novel compound was isolated, identified, and its chemical structure was determined from the extract of the roots of Senna velutina. In addition, we sought to evaluate the anticancer potential of this molecule against melanoma and leukemic cell lines and identify the pathways of cell death involved. To this end, a novel anthraquinone was isolated from the barks of the roots of S. velutina, analyzed by HPLC-DAD, and its molecular structure was determined by nuclear magnetic resonance (NMR). Subsequently, their cytotoxic activity was evaluated by the (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) method against non-cancerous, melanoma, and leukemic cells. The migration of melanoma cells was evaluated by the scratch assay. The apoptosis process, caspase-3 activation, analysis of mitochondrial membrane potential, and measurement of ROS were evaluated by flow cytometry technique. In addition, the pharmacological cell death inhibitors NEC-1, RIP-1, BAPTA, Z-VAD, and Z-DEVD were used to confirm the related cell death mechanisms. With the results, it was possible to elucidate the novel compound characterized as 2'-OH-Torosaol I. In normal cells, the compound showed no cytotoxicity in PBMC but reduced the cell viability of all melanoma and leukemic cell lines evaluated. 2'-OH-Torosaol I inhibited chemotaxis of B16F10-Nex2, SK-Mel-19, SK-Mel-28 and SK-Mel-103. The cytotoxicity of the compound was induced by apoptosis via the intrinsic pathway with reduced mitochondrial membrane potential, increased levels of reactive oxygen species, and activation of caspase-3. In addition, the inhibitors demonstrated the involvement of necroptosis and Ca²⁺ in the death process and confirmed caspase-dependent apoptosis death as one of the main programmed cell death pathways induced by 2'-OH-Torosaol I. Taken together, the data characterize the novel anthraquinone 2'-OH-Torosaol I, demonstrating its anticancer activity and potential application in cancer therapy.

Biological role and diagnostic utility of ribosomal protein L23a pseudogene 53 in cutaneous melanoma

Background

Skin melanoma is one of the deadliest types of skin cancer and develops from melanocytes. The genetic aberrations in protein-coding genes are well characterized, but little is known about changes in non-coding RNAs (ncRNAs) such as pseudogenes. Ribosomal protein pseudogenes (RPPs) have been described as the largest group of pseudogenes which are dispersed in the human genome.

Materials and methids

We looked deeply at the role of one of them, ribosomal protein L23a pseudogene 53 (RPL23AP53), and its potential diagnostic use. The expression level of RPL23AP53 was profiled in melanoma cell lines using real time quantitative reverse transcription polymerase chain reaction (qRT-PCR) and analyzed based on the Cancer Genome Atlas (TCGA) data depending on BRAF status and clinicopathological parameters. Cellular phenotype, which was associated with RPL23AP53 levels, was described based on the REACTOME pathway browser, Gene Set Enrichment Analysis (GSEA) analysis as well as Immune and ESTIMATE Scores.

Results

We indicted in vitro changes in RPL23AP53 level depending on a cell line, and based on in silico analysis of TCGA samples demonstrated significant differences in RPL23AP53 expression between primary and metastatic melanoma, as well as correlation between RPL23AP53 and overall survival. No differences depending on BRAF status were observed. RPL23AP53 is associated with several signaling pathways and cellular processes.

Conclusions

This study showed that patients with higher expression of RPL23AP53 displayed changed infiltration of lymphocytes, macrophages, and neutrophils compared to groups with lower expression of RPL23AP53. RPL23AP53 pseudogene is differently expressed in melanoma compared with normal tissue and its expression is associated with cellular proliferation. Thus, it may be considered as an indicator of patients' survival and a marker for the immune profile assessment.

Transformer-Based Approach to Melanoma Detection

Melanoma is a malignant cancer type which develops when DNA damage occurs (mainly due to environmental factors such as ultraviolet rays). Often, melanoma results in intense and aggressive cell growth that, if not caught in time, can bring one toward death. Thus, early identification at the initial stage is fundamental to stopping the spread of cancer. In this paper, a ViT-based architecture able to classify melanoma versus non-cancerous lesions is presented. The proposed predictive model is trained and tested on public skin cancer data from the ISIC challenge, and the obtained results are highly promising. Different classifier configurations are considered and analyzed in order to find the most discriminating one. The best one reached an accuracy of 0.948, sensitivity of 0.928, specificity of 0.967, and AUROC of 0.948.

The role of histological subtypes in the survival of patients diagnosed with cutaneous or mucosal melanoma in the United States of America

BACKGROUND

Literature presents limited information on histological subtypes and their association with other factors influencing the survival of melanoma patients. To explore the risk of death due to melanoma associated with histological subtypes, this retrospective study used the Surveillance, Epidemiology, and End Results program (SEER) data from 1998 to 2019.

METHODS

A total of 27,532 patients consisting of 15,527 males and 12,005 females. The Hypertabastic Accelerated Failure Time model was used to analyze the impact of histology on the survival of patients with cutaneous or mucosal melanoma.

RESULTS

The median survival time (MST) for cutaneous patients was 149 months, whereas those diagnosed with mucosal melanoma was 34 months. Nodular melanoma had a hazard ratio of 3.40 [95% CI: (2.94, 3.94)] compared to lentigo maligna melanoma. Across all histological subtypes, females had a longer MST, when compared to males. The hazard ratio (HR) of distant to localized melanoma was 9.56 [95% CI: (7.58, 12.07)].

CONCLUSIONS

Knowledge of patients' histological subtypes and their hazard assessment would enable clinicians and healthcare providers to perform personalized treatment, resulting in a lower risk of complication and higher survivability of melanoma patients. Significant factors were stage of the disease, age, histology, sex, and income. Focus should be placed on high-risk populations with severe and aggressive histological subtypes. Programs that emphasize preventive measures such as awareness, education, and early screening could reduce risk.

Melanin Stacking Differences in Pigmented and Non-Pigmented Melanomas: Quantitative Differentiation between Pigmented and Non-Pigmented Melanomas Based on Light-Scattering Properties

Cutaneous melanoma is a cancer with metastatic potential characterized by varying amounts of pigment-producing melanocytes, and it is one of the most aggressive and fatal forms of skin malignancy, with several hundreds of thousands of cases each year. Early detection and therapy can lead to decreased morbidity and decreased cost of therapy. In the clinic, this often translates to annual skin screenings, especially for high-risk patients, and generous use of the ABCDE (asymmetry, border irregularity, color, diameter, evolving) criteria. We have used a new technique termed vibrational optical coherence tomography (VOCT) to non-invasively differentiate between pigmented and non-pigmented melanomas in a pilot study. The VOCT results reported in this study indicate that both pigmented and non-pigmented melanomas have similar characteristics, including new 80, 130, and 250 Hz peaks. Pigmented melanomas have larger 80 Hz peaks and smaller 250 Hz peaks than non-pigmented cancers. The 80 and 250 Hz peaks can be used to quantitative characterize differences between different melanomas. In addition, infrared light penetration depths indicated that melanin in pigmented melanomas has higher packing densities than in non-pigmented lesions. Using machine learning techniques, the sensitivity and specificity of differentiating skin cancers from normal skin are shown to range from about 78% to over 90% in this pilot study. It is proposed that using AI on both lesion histopathology and mechanovibrational peak heights may provide even higher specificity and sensitivity for differentiating the metastatic potential of different melanocytic lesions.

Phenolic Compounds Contribution to Portuguese Propolis Anti-Melanoma Activity

Melanoma is the deadliest type of skin cancer, with about 61,000 deaths annually worldwide. Late diagnosis increases mortality rates due to melanoma’s capacity to metastasise rapidly and patients’ resistance to the available conventional therapies. Consequently, the interest in natural products as a strategy for drug discovery has been emerging. Propolis, a natural product produced by bees, has several biological properties, including anticancer effects. Propolis from Gerês is one of the most studied Portuguese propolis. Our group has previously demonstrated that an ethanol extract of Gerês propolis collected in 2018 (G18.EE) and its fractions (n-hexane, ethyl acetate, and n-butanol) decrease melanoma cell viability. Out of all the fractions, G18.EE-n-BuOH showed the highest potential as a melanoma pharmacological therapy. Thus, in this work, G18.EE-n-BuOH was fractioned into 17 subfractions whose effect was evaluated in A375 BRAF-mutated melanoma cells. The subfractions with the highest cytotoxic activity were analysed by UPLC-DAD-ESI/MSn in an attempt to understand which phenolic compounds could account for the anti-melanoma activity. The compounds identified are typical of the Gerês propolis, and some of them have already been linked with antitumor effectiveness. These results reaffirm that propolis compounds can be a source of new drugs and the isolation of compounds could allow its use in traditional medicine.

PRIMARY MULTIPLE MALIGNANT SKIN TUMORS: MELANOMA AND BASAL CELL CARCINOMA

The incidence of skin melanoma in the world is growing every year. Despite advances in diagnostics, the identification of the primary focus of melanoma in some cases is still difficult. The natural course sometimes manifests only with the appearance of melanoma metastases, which can mimic other diseases. Patient S., 52 years old, was admitted to the FCBRN of FMBA of Russia with complaints on periodic systemic dizziness, headaches of a pressing nature, episodes of speech impairment over the past three months. According to the brain MRI-scan results, a volumetric formation of the left frontal lobe was revealed. Upon examination, two non-pigmented lesions were found on the skin of the scalp and forehead. Due to the presence of focal neurological symptoms, it was decided to remove the brain tumor using neurophysiological monitoring and the scalp skin lesion, with histological verification. Morphological diagnosis of the removed brain tumor was a metastasis of amelanotic epithelioid melanoma. The skin lesion was basal cell carcinoma. Thus, the patient had primarily multiple malignant tumors: metastatic melanoma and basal cell carcinoma. The primary focus of melanoma could not be identified by available noninvasive research methods. The patient was referred to an oncologist to decide on the tactics of further examination and treatment. To date, the patient has been treated according to the scheme sh0876 1 line 1 course of pembrolizumab 400mg IV, cycle 42 days.

Photography as the Sole Means of Proof: Medical Liability in Dermatology

Malignant melanoma is a cutaneous malignancy resulting from the uncontrolled proliferation of melanocytes and poses a challenge diagnostically because neoplastic lesions can mimic benign lesions, which are much more common in the population. Doctors, when they suspect the presence of melanoma, arrange for its removal and the performance of a histological examination to ascertain its diagnosis; in cases where the dermatoscopic examination is indicative of benignity, however, after the lesion is removed, histological examination is not always performed, a very dangerous occurrence and a harbinger of further medico-legal problems. The authors present a court litigation case of an “alleged” failure to diagnose malignant melanoma in a patient who died of brain metastases from melanoma in the absence of a certain location of the primary tumor: the physician who had removed a benign lesion a few months earlier was sued, and only thanks to the presence of photographic documentation was the health care provider able to prove his extraneousness. The aim of this paper is to formulate a proposal for a dermatological protocol to be followed in cases of excisions of benign skin lesions with a twofold purpose: on the one hand, to be able to prove, in a judicial context, the right action on the part of the sanitarians; on the other hand, to avoid the rise of so-called “defensive medicine”.

(De)troubling transparency: artificial intelligence (AI) for clinical applications

Artificial intelligence (AI) and machine learning (ML) techniques occupy a prominent role in medical research in terms of the innovation and development of new technologies. However, while many perceive AI as a technology of promise and hope-one that is allowing for more early and accurate diagnosis-the acceptance of AI and ML technologies in hospitals remains low. A major reason for this is the lack of transparency associated with these technologies, in particular epistemic transparency, which results in AI disturbing or troubling established knowledge practices in clinical contexts. In this article, we describe the development process of one AI application for a clinical setting. We show how epistemic transparency is negotiated and co-produced in close collaboration between AI developers and clinicians and biomedical scientists, forming the context in which AI is accepted as an epistemic operator. Drawing on qualitative research with collaborative researchers developing an AI technology for the early diagnosis of a rare respiratory disease (pulmonary hypertension/PH), this paper examines how including clinicians and clinical scientists in the collaborative practices of AI developers de-troubles transparency. Our research shows how de-troubling transparency occurs in three dimensions of AI development relating to PH: querying of data sets, building software and training the model The close collaboration results in an AI application that is at once social and technological: it integrates and inscribes into the technology the knowledge processes of the different participants in its development. We suggest that it is a misnomer to call these applications 'artificial' intelligence, and that they would be better developed and implemented if they were reframed as forms of sociotechnical intelligence.

PPARs and the Kynurenine Pathway in Melanoma-Potential Biological Interactions

Peroxisome proliferator-activated receptors (PPARs) are ligand-activated transcription factors involved in various physiological and pathological processes within the skin. PPARs regulate several processes in one of the most aggressive skin cancers, melanoma, including proliferation, cell cycle, metabolic homeostasis, cell death, and metastasis. In this review, we focused not only on the biological activity of PPAR isoforms in melanoma initiation, progression, and metastasis but also on potential biological interactions between the PPAR signaling and the kynurenine pathways. The kynurenine pathway is a major pathway of tryptophan metabolism leading to nicotinamide adenine dinucleotide (NAD+) production. Importantly, various tryptophan metabolites exert biological activity toward cancer cells, including melanoma. Previous studies confirmed the functional relationship between PPAR and the kynurenine pathway in skeletal muscles. Despite the fact this interaction has not been reported in melanoma to date, some bioinformatics data and biological activity of PPAR ligands and tryptophan metabolites may suggest a potential involvement of these metabolic and signaling pathways in melanoma initiation, progression, and metastasis. Importantly, the possible relationship between the PPAR signaling pathway and the kynurenine pathway may relate not only to the direct biological effect on melanoma cells but also to the tumor microenvironment and the immune system.

Incidence Trends of Melanoma and Nonmelanoma Skin Cancers in Jordan From 2000 to 2016

PURPOSE

Skin cancers are among the commonest cancers worldwide, and the incidence of melanoma and non-melanoma skin cancer (NMSC) continues to rise worldwide. However, there are no comprehensive reports on skin cancer incidence in Jordan during the past two decades. This report investigates the incidence of skin cancers in Jordan, in particular their time trends for the period 2000-2016.

MATERIALS AND METHODS

Data on malignant melanomas (MMs), squamous cells carcinomas (SCCs), and basal cell carcinomas (BCCs) were extracted from the Jordan Cancer Registry for the period between 2000 and 2016. Age-specific and overall age-standardized incidence rates (ASIRs) were computed.

RESULTS

Two thousand seventy patients were diagnosed with at least one BCC, 1,364 with SCC, and 258 with MM. ASIRs were 28, 19, and 4 per 100,000 person-years for BCC, SCC, and MM, respectively. The BCC:SCC incidence ratio was 1.47:1. The risk of men developing SCCs was significantly higher than women (relative risks [RRs], 1.311; 95% CI, 1.197 to 1.436), but significantly lower for BCCs (RR, 0.929; 95% CI, 0.877 to 0.984) or melanomas (RR, 0.465; 95% CI, 0.366 to 0.591). Persons older than 60 years were at a significantly higher risk of developing SCCs (RR, 1.225; 95% CI, 1.119 to 1.340) or melanomas (RR, 2.445; 95% CI, 1.925 to 3.104), but at a significantly lower risk of developing BCCs (RR, 0.885; 95% CI, 0.832 to 0.941). The overall incidence rates of SCCs, BCCs, and melanomas increased over the 16-year study period, but this was not statistically significant.

CONCLUSION

To our knowledge, this is the largest epidemiologic study regarding skin cancers in Jordan and in the Arab world. Despite low incidence rates in this study, rates are higher than reported regional figures. This is likely due to standardized, centralized, and mandatory reporting of skin cancers, including NMSC.

A Comprehensive Analysis of Cutaneous Melanoma Patients in Greece Based on Multi-Omic Data

Cutaneous melanoma (CM) is the most aggressive type of skin cancer, and it is characterised by high mutational load and heterogeneity. In this study, we aimed to analyse the genomic and transcriptomic profile of primary melanomas from forty-six Formalin-Fixed, Paraffin-Embedded (FFPE) tissues from Greek patients. Molecular analysis for both germline and somatic variations was performed in genomic DNA from peripheral blood and melanoma samples, respectively, exploiting whole exome and targeted sequencing, and transcriptomic analysis. Detailed clinicopathological data were also included in our analyses and previously reported associations with specific mutations were recognised. Most analysed samples (43/46) were found to harbour at least one clinically actionable somatic variant. A subset of samples was profiled at the transcriptomic level, and it was shown that specific melanoma phenotypic states could be inferred from bulk RNA isolated from FFPE primary melanoma tissue. Integrative bioinformatics analyses, including variant prioritisation, differential gene expression analysis, and functional and gene set enrichment analysis by group and per sample, were conducted and molecular circuits that are implicated in melanoma cell programmes were highlighted. Integration of mutational and transcriptomic data in CM characterisation could shed light on genes and pathways that support the maintenance of phenotypic states encrypted into heterogeneous primary tumours.

First-in-human phase I dose-escalation and dose-expansion trial of the selective MEK inhibitor HL-085 in patients with advanced melanoma harboring NRAS mutations

BACKGROUND

HL-085 is a selective, orally administered MEK1/2 inhibitor. We aimed to evaluate the safety and efficacy of HL-085 in patients with advanced melanoma harboring NRAS mutations.

METHODS

This was a multicenter phase 1 study. HL-085 was administered twice daily in a standard 3 + 3 dose-escalation design (10 dose cohorts; 0.5-18 mg twice daily), followed by dose expansion at the recommended phase II dose (RP2D). The primary endpoints included tolerability, dose-limiting toxicity (DLT), maximum tolerated dose (MTD) and RP2D.

RESULTS

Between September 13, 2017, and January 18, 2021, 42 patients were enrolled (dose escalation phase: n = 30; dose expansion phase: n = 12). No DLT was reported during dose escalation and MTD was not reached with HL-085 doses up to 18 mg twice daily. The RP2D was 12 mg twice daily. The most common all-grade drug-related adverse events (AEs) across all dose levels were rash (61.9%), increased creatine phosphokinase (CK, 59.5%), face edema (50.0%), increased aspartate aminotransferase (47.6%), peripheral edema (40.5%), diarrhea (33.3%), alanine aminotransferase (33.3%), and paronychia (19.0%), most of which were grade 1 and 2. Most frequency of grade ≥ 3 AEs were CK (14.2%), asthenia (7.1%), peripheral edema (4.8%), and acneiform dermatitis (4.8%). In the cohort of 12 mg twice daily dose (15 patients), confirmed objective response rate was 26.7%; disease control rate was 86.7%; median duration of response was 2.9 months; median progression-free survival was 3.6 months.

CONCLUSIONS

The HL-085 showed acceptable tolerability and substantial clinical activity in patients with advanced melanoma harboring NRAS mutations.

TRIAL REGISTRATION

Trial registration ClinicalTrials.gov number: NCT03973151.

GPR4 in the pH-dependent migration of melanoma cells in the tumor microenvironment

Due to its high metastatic potential, malignant melanoma is one of the deadliest skin cancers. In melanoma as well as in other cancers, acidification of the tumor microenvironment (=TME, inverse pH-gradient) is a well-known driver of tumor progression and metastasis. Membrane-bound receptors, such as the proton-sensitive GPCR (pH-GPCR) GPR4, are considered as potential initiators of the signalling cascades relevant to malignant transformation. In this study, we investigated the pH-dependent migration of GPR4 wildtype/overexpressing SK-Mel-28 cells using an impedance-based electrical wounding and migration assay and classical Boyden chamber experiments. Migration of GPR4 overexpressing SK-Mel-28 cells was enhanced in a range of pH 6.5-7.5 as compared to controls in the impedance-based electrical wounding and migration assay. In Boyden chamber experiments, GPR4 overexpression only increased migration at pH 7.5 in a Matrigel-free setup, but not at pH 6.5. Results indicate that GPR4 is involved in the migration of melanoma cells, especially in the tumor periphery, and that this process is affected by pH in the TME.

Microneedles-mediated drug delivery system for the diagnosis and treatment of melanoma

As an emerging novel drug delivery system, microneedles (MNs) have a wide range of applications in the medical field. They can overcome the physiological barriers of the skin, penetrate the outermost skin of the human body, and form hundreds of reversible microchannels to enhance the penetration of drugs and deliver drugs to the diseased sites. So they have great applications in the diagnosis and treatment of melanoma. Melanoma is a kind of malignant tumor, the survival rate of patients with metastases is extremely low. The traditional methods of surgery and drug treatment for melanoma are often accompanied by large adverse reactions in the whole body, and the drug concentration is low. The use of MNs for transdermal administration can increase the drug concentration, reduce adverse reactions in the treatment process, and have good therapeutic effect on melanoma. This paper introduced various types of MNs and their preparation methods, summarized the diagnosis and various treatment options for melanoma with MNs, focused on the treatment of melanoma with dissolved MNs, and made prospect of MNs-mediated transdermal drug delivery in the treatment of melanoma.

Melanoma Tumour Vascularization and Tissue-Resident Endothelial Progenitor Cells

Simple Summary

Melanoma is the most aggressive and potentially lethal form of skin cancer. Research over recent decades has highlighted the role of tumour vasculature in altering the metabolic function of cancer cells, infiltration of immune cells, and cancer cell dissemination. However, variations in the modes of vessel formation in melanoma have made this process difficult to target. In particular, the role of endothelial progenitor cells in melanoma vascularization-promoting vasculogenesis begins to be understood. Progenitor recruitment, vessel formation, and paracrine activity are among the steps contributing to tumour metastasis and affecting the impact of anti-angiogenic drugs, as detailed in this review.

Abstract

The aggressiveness of solid cancers, such as melanoma, relies on their metastatic potential. It has become evident that this key cause of mortality is largely conferred by the tumour-associated stromal cells, especially endothelial cells. In addition to their essential role in the formation of the tumour vasculature, endothelial cells significantly contribute to the establishment of the tumour microenvironment, thus enabling the dissemination of cancer cells. Melanoma tumour vascularization occurs through diverse biological processes. Vasculogenesis is the formation of de novo blood vessels from endothelial progenitor cells (EPCs), and recent research has shown the role of EPCs in melanoma tumour vascularization. A more detailed understanding of the complex role of EPCs and how they contribute to the abnormal vessel structures in tumours is of importance. Moreover, anti-angiogenic drugs have a limited effect on melanoma tumour vascularization, and the role of these drugs on EPCs remains to be clarified. Overall, targeting cancer vasculature remains a challenge, and the role of anti-angiogenic drugs and combination therapies in melanoma, a focus of this review, is an area of extensive exploration.

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.

Modern views on skin biopsy in the diagnostic algorithm of dermatooncological diseases

Background. Malignant neoplasms of the skin are fairly common tumors in the world population and among the population of Ukraine. The main method of diagnosing skintumors is a biopsy, which allows establishing a diagnosis at an early stage and ensures the cure of most patients. Purpose. To evaluate modern recommendations for skin biopsy in the diagnosis of dermato-onсological diseases. Materials and methods. The search for sources of information was conducted using the MEDLINE/PubMed, EMBASE/ExcerptaMedica, CochraneLibrary, PubMed та Google Scholar databases using the following keywords: skin biopsy, skin tumors, diagnosis, melanoma. Among the identified sources, works without statistical analysis, descriptions of individual cases, articles without conclusions, and sources with duplicate results were excluded. The search depth was 10 years. Results. As a result of the conducted search, 57 publications were found that corresponded to the declared purpose. The most common methods are: puncture, shaving, excisional and incisional biopsy. Most guidelines recommend full-thickness excisional biopsy as the preferred procedure for the diagnosis of suspected melanoma. It is indicated that a statistically significant mortality rate was found in the puncture biopsy group. Most observations showed no significant differences in melanoma recurrence between excisional biopsy and puncture groups. Given the clinical diversity of melanoma, there is no uniformity in the types of biopsies performed to diagnose melanoma. The most inaccurate method turned out to be the punch biopsy method, which is associated with an increased risk of underdiagnosis of melanoma. Conclusions. A skin biopsy is a mandatory first step to establish a definitive diagnosis of a skin tumor. Excisional complete biopsy is the most justified in most cases of diagnosis. Rational biopsy technique remains an issue that needs further study.

Structural and Biofunctional Insights into the Cyclo(Pro-Pro-Phe-Phe-) Scaffold from Experimental and In Silico Studies: Melanoma and Beyond

Short peptides have great potential as safe and effective anticancer drug leads. Herein, the influence of short cyclic peptides containing the Pro-Pro-Phe-Phe sequence on patient-derived melanoma cells was investigated. Cyclic peptides such as cyclo(Leu-Ile-Ile-Leu-Val-Pro-Pro-Phe-Phe-), called CLA, and cyclo(Pro-homoPro-β3homoPhe-Phe-), called P11, exert the cytotoxic and the cytostatic effects in melanoma cells, respectively. CLA was the most active peptide as it reduced the viability of melanoma cells to 50% of control at about 10 µM, whereas P11 at about 40 µM after 48 h incubation. Interestingly, a linear derivative of P11 did not induce any effect in melanoma cells confirming previous studies showing that cyclic peptides exert better biological activity compared to their linear counterparts. According to in silico predictions, cyclic tetrapeptides show a better pharmacokinetic and toxic profile to humans than CLA. Notably, the spatial structure of those peptides containing synthetic amino acids has not been explored yet. In the Cambridge Structural Database, there is only one such cyclic tetrapeptide, cyclo((R)-β2homoPhe-D-Pro-Lys-Phe-), while in the Protein Data Bank—none. Therefore, we report the first crystal structure of cyclo(Pro-Pro-β3homoPhe-Phe-), denoted as 4B8M, a close analog of P11, which is crucial for drug discovery. Comparative molecular and supramolecular analysis of both structures was performed. The DFT findings revealed that 4B8M is well interpreted in the water solution. The results of complex Hirshfeld surface investigations on the cooperativity of interatomic contacts in terms of electrostatic and energetic features are provided. In short, the enrichment ratio revealed O…H/H…O and C…H/H…C as privileged intercontacts in the crystals in relation to basic and large supramolecular H-bonding synthon patterns. Furthermore, the ability of self-assemble 4B8M leading to a nanotubular structure is also discussed.

The Dark Side of Melanin Secretion in Cutaneous Melanoma Aggressiveness

Skin cancers are among the most common cancers worldwide and are increasingly prevalent. Cutaneous melanoma (CM) is characterized by the malignant transformation of melanocytes in the epidermis. Although CM shows lower incidence than other skin cancers, it is the most aggressive and responsible for the vast majority of skin cancer-related deaths. Indeed, 75% of patients present with invasive or metastatic tumors, even after surgical excision. In CM, the photoprotective pigment melanin, which is produced by melanocytes, plays a central role in the pathology of the disease. Melanin absorbs ultraviolet radiation and scavenges reactive oxygen/nitrogen species (ROS/RNS) resulting from the radiation exposure. However, the scavenged ROS/RNS modify melanin and lead to the induction of signature DNA damage in CM cells, namely cyclobutane pyrimidine dimers, which are known to promote CM immortalization and carcinogenesis. Despite triggering the malignant transformation of melanocytes and promoting initial tumor growth, the presence of melanin inside CM cells is described to negatively regulate their invasiveness by increasing cell stiffness and reducing elasticity. Emerging evidence also indicates that melanin secreted from CM cells is required for the immunomodulation of tumor microenvironment. Indeed, melanin transforms dermal fibroblasts in cancer-associated fibroblasts, suppresses the immune system and promotes tumor angiogenesis, thus sustaining CM progression and metastasis. Here, we review the current knowledge on the role of melanin secretion in CM aggressiveness and the molecular machinery involved, as well as the impact in tumor microenvironment and immune responses. A better understanding of this role and the molecular players involved could enable the modulation of melanin secretion to become a therapeutic strategy to impair CM invasion and metastasis and, hence, reduce the burden of CM-associated deaths.

Machine Learning and Deep Learning Algorithms for Skin Cancer Classification from Dermoscopic Images

We carry out a critical assessment of machine learning and deep learning models for the classification of skin tumors. Machine learning (ML) algorithms tested in this work include logistic regression, linear discriminant analysis, k-nearest neighbors classifier, decision tree classifier and Gaussian naive Bayes, while deep learning (DL) models employed are either based on a custom Convolutional Neural Network model, or leverage transfer learning via the use of pre-trained models (VGG16, Xception and ResNet50). We find that DL models, with accuracies up to 0.88, all outperform ML models. ML models exhibit accuracies below 0.72, which can be increased to up to 0.75 with ensemble learning. To further assess the performance of DL models, we test them on a larger and more imbalanced dataset. Metrics, such as the F-score and accuracy, indicate that, after fine-tuning, pre-trained models perform extremely well for skin tumor classification. This is most notably the case for VGG16, which exhibits an F-score of 0.88 and an accuracy of 0.88 on the smaller database, and metrics of 0.70 and 0.88, respectively, on the larger database.

Characterizing Malignant Melanoma Clinically Resembling Seborrheic Keratosis Using Deep Knowledge Transfer

Simple Summary

Malignant melanomas (MMs) with aypical clinical presentation constitute a diagnostic pitfall, and false negatives carry the risk of a diagnostic delay and improper disease management. Among the most common, challenging presentation forms of MMs are those that clinically resemble seborrheic keratosis (SK). On the other hand, SK may mimic melanoma, producing ‘false positive overdiagnosis’ and leading to needless excisions. The evolving efficiency of deep learning algorithms in image recognition and the availability of large image databases have accelerated the development of advanced computer-aided systems for melanoma detection. In the present study, we used image data from the International Skin Image Collaboration archive to explore the capacity of deep knowledge transfer in the challenging diagnostic task of the atypical skin tumors of MM and SK.

Abstract

Malignant melanomas resembling seborrheic keratosis (SK-like MMs) are atypical, challenging to diagnose melanoma cases that carry the risk of delayed diagnosis and inadequate treatment. On the other hand, SK may mimic melanoma, producing a ‘false positive’ with unnecessary lesion excisions. The present study proposes a computer-based approach using dermoscopy images for the characterization of SΚ-like MMs. Dermoscopic images were retrieved from the International Skin Imaging Collaboration archive. Exploiting image embeddings from pretrained convolutional network VGG16, we trained a support vector machine (SVM) classification model on a data set of 667 images. SVM optimal hyperparameter selection was carried out using the Bayesian optimization method. The classifier was tested on an independent data set of 311 images with atypical appearance: MMs had an absence of pigmented network and had an existence of milia-like cysts. SK lacked milia-like cysts and had a pigmented network. Atypical MMs were characterized with a sensitivity and specificity of 78.6% and 84.5%, respectively. The advent of deep learning in image recognition has attracted the interest of computer science towards improved skin lesion diagnosis. Open-source, public access archives of skin images empower further the implementation and validation of computer-based systems that might contribute significantly to complex clinical diagnostic problems such as the characterization of SK-like MMs.

Investigation of Lupeol as Anti-Melanoma Agent: An In Vitro-In Ovo Perspective

Malignant melanoma (MM) represents the most life-threatening skin cancer worldwide, with a narrow and inefficient chemotherapeutic arsenal available in advanced disease stages. Lupeol (LUP) is a triterpenoid-type phytochemical possessing a broad spectrum of pharmacological properties, including a potent anticancer effect against several neoplasms (e.g., colorectal, lung, and liver). However, its potential as an anti-melanoma agent has been investigated to a lesser extent. The current study focused on exploring the impact of LUP against two human MM cell lines (A375 and RPMI-7951) in terms of cell viability, confluence, morphology, cytoskeletal distribution, nuclear aspect, and migration. Additionally, the in ovo antiangiogenic effect has been also examined. The in vitro results indicated concentration-dependent and selective cytotoxicity against both MM cell lines, with estimated IC₅₀ values of 66.59 ± 2.20 for A375, and 45.54 ± 1.48 for RPMI-7951, respectively, accompanied by a reduced cell confluence, apoptosis-specific nuclear features, reorganization of cytoskeletal components, and inhibited cell migration. In ovo, LUP interfered with the process of angiogenesis by reducing the formation of neovascularization. Despite the potential anti-melanoma effect illustrated in our in vitro-in ovo study, further investigations are required to elucidate the underlying LUP-induced effects in A375 and RPMI-7951 MM cells.

Clinical Significance of Distant Metastasis-Free Survival (DMFS) in Melanoma: A Narrative Review from Adjuvant Clinical Trials

Cutaneous melanoma is the most dangerous skin cancer, with high death rates in advanced stages. To assess the impact of each treatment on patient outcomes, most studies use relapse-free survival (RFS) as a primary endpoint and distant metastasis-free survival (DMFS) as a secondary endpoint. The aim of this narrative review of the main adjuvant studies for resected stage III/IV melanoma, with a specific focus on DMFS, is to evaluate DMFS trends and their potential association with RFS, identify which treatments are possibly associated with better outcomes in terms of DMFS and their potential predictive factors, and discuss DMFS trends in terms of patient management in daily practice. We outline the impact of each available treatment option on DMFS and RFS according to the years of follow-up and compare data from different studies. Overall, the trends of DMFS closely follow those of RFS, with most patients relapsing at visceral rather than regional sites. As it captures the burden of patients who develop distant relapse, DMFS could be considered a primary endpoint, in addition to RFS, in adjuvant trials, identifying patients whose relapse is associated with a worse prognosis and who may need further systemic treatment.

Prognostic Value of Interleukin-32 Expression and Its Correlation with the Infiltration of Natural Killer Cells in Cutaneous Melanoma

Interleukin-32 (IL-32) is well known as a proinflammatory cytokine that is expressed in various immune cells and cancers. However, the clinical relevance of IL-32 expression in cutaneous melanoma has not been comprehensively studied. Here, we identified the prognostic value of IL32 expression using various systematic multiomic analyses. The IL32 expressions were significantly higher in cutaneous melanoma than in normal tissue, and Kaplan-Meier survival analysis showed a correlation between IL32 expression and good prognosis in cutaneous melanoma patients. In addition, we analyzed the correlation between IL32 expression and the infiltration of natural killer (NK) cells to identify a relevant mechanism between IL32 expression and prognosis in cutaneous melanoma (p = 0.00031). In the relationship between IL32 expression and the infiltration of NK cells, a negative correlation was found in resting NK cells (rho = -0.38, p = 3.95 × 10^-17) whereas a strong positive correlation was observed only in active NK cells (rho = 0.374, p = 1.23 × 10^-16). Moreover, IL32 expression was markedly positively correlated with the cytolytic molecules, such as granzyme and perforin. These data suggest that IL32 expression may increase patient survival through the infiltration and activation of NK cells, representative anticancer effector cells, in cutaneous melanoma. Collectively, this study provides the prognostic value of IL32 expression and its potential role as an effective predictive biomarker for NK cell infiltration in cutaneous melanoma.

Rutin Exerts Cytotoxic and Senescence-Inducing Properties in Human Melanoma Cells

Malignant melanoma represents the deadliest type of skin cancer with narrow treatment options in advanced stages. Herbal constituents possessing anticancer properties occupy a particular spot in melanoma research as potential chemotherapeutics. Rutin (RUT) is a natural compound exerting antioxidant, antimicrobial, anti-inflammatory, UV-filtering, and SPF-enhancing activities that are beneficial to the skin; however, its effect as an anti-melanoma agent is less investigated. The current study is focused on assessing the cytotoxic potential of RUT against two different human melanoma cell lines: RPMI-7951 and SK-MEL-28 by evaluating its impact in terms of cell viability, cells’ morphology, and nuclear aspect assessment, and senescence-inducing properties. The results indicate a dose-dependent decrease in the viability of both cell lines, with calculated IC₅₀ values of 64.49 ± 13.27 µM for RPMI-7951 cells and 47.44 ± 2.41 µM for SK-MEL-28, respectively, accompanied by a visible reduction in the cell confluency and apoptotic features within the cell nuclei. RUT exerted a senescence-inducing property highlighted by the elevated expression of senescent-associated beta-galactosidase (SA-β-gal) in SK-MEL-28 cells. Despite the in vitro anti-melanoma effect revealed by our results, further studies are required to elucidate the mechanisms of RUT-induced cytotoxicity and senescence in melanoma cells.

Profiling Cancer-Associated Fibroblasts in Melanoma

Solid tumors are complex systems characterized by dynamic interactions between neoplastic cells, non-tumoral cells, and extracellular components. Among all the stromal cells that populate tumor microenvironment, fibroblasts are the most abundant elements and are critically involved in disease progression. Cancer-associated fibroblasts (CAFs) have pleiotropic functions in tumor growth and extracellular matrix remodeling implicated in local invasion and distant metastasis. CAFs additionally participate in the inflammatory response of the tumor site by releasing a variety of chemokines and cytokines. It is becoming clear that understanding the dynamic, mutual melanoma-fibroblast relationship would enable treatment options to be amplified. To better characterize melanoma-associated fibroblasts, here we analyzed low-passage primary CAFs derived from advanced-stage primary skin melanomas, focusing on the immuno-phenotype. Furthermore, we assessed the expression of several CAF markers and the production of growth factors. To deepen the study of CAF-melanoma cell crosstalk, we employed CAF-derived supernatants and trans-well co-culture systems to evaluate the influences of CAFs on (i) the motogenic ability of melanoma cells, (ii) the chemotherapy-induced cytotoxicity, and (iii) the release of mediators active in modulating tumor growth and spread.