Chemokine profiling of melanoma-macrophage crosstalk identifies CCL8 and CCL15 as prognostic factors in cutaneous melanoma.

During cancer evolution, tumor cells attract and dynamically interact with monocytes/macrophages. To find biomarkers of disease progression in human melanoma, we used unbiased RNA sequencing and secretome analyses of tumor-macrophage co-cultures. Pathway analysis of genes differentially modulated in human macrophages exposed to melanoma cells revealed a general upregulation of inflammatory hallmark gene sets, particularly chemokines. A selective group of chemokines, including CCL8, CCL15, and CCL20, was actively secreted upon melanoma-macrophage co-culture. Because we previously described the role of CCL20 in melanoma, we focused our study on CCL8 and CCL15 and confirmed that in vitro both chemokines contributed to melanoma survival, proliferation, and 3D invasion through CCR1 signaling. In vivo, both chemokines enhanced primary tumor growth, spontaneous lung metastasis, and circulating tumor cell survival and lung colonization in mouse xenograft models. Finally, we explored the clinical significance of CCL8 and CCL15 expression in human skin melanoma, screening a collection of 67 primary melanoma samples, using multicolor fluorescence and quantitative image analysis of chemokine-chemokine receptor content at the single-cell level. Primary skin melanomas displayed high CCR1 expression, but there was no difference in its level of expression between metastatic and nonmetastatic cases. By contrast, comparative analysis of these two clinically divergent groups showed a highly significant difference in the cancer cell content of CCL8 (p = 0.025) and CCL15 (p < 0.0001). Kaplan-Meier curves showed that a high content of CCL8 or CCL15 in cancer cells correlated with shorter disease-free and overall survival (log-rank test, p < 0.001). Our results highlight the role of CCL8 and CCL15, which are highly induced by melanoma-macrophage interactions in biologically aggressive primary melanomas and could be clinically applicable biomarkers for patient profiling. © 2024 The Pathological Society of Great Britain and Ireland.

Who Will Have a Second Melanoma? A Prospective Longitudinal Study in Patients without Any Genetic Predisposition.

BACKGROUND: Melanoma patients have a higher risk of developing additional melanomas. Predisposing factors of a second primary melanoma in patients without any genetic predisposition are not well established. OBJECTIVES: The aim of this study was to identify risk factors related to the development of a second primary melanoma in order to know which patients should be followed up closely. METHODS: A longitudinal study was performed at Hospital Gregorio Marañón (Madrid, Spain), based on follow-up data of patients diagnosed with cutaneous melanoma from 1998 to 2020. RESULTS: After a median follow-up of 82 months, 58 out of 1523 (3.8%) patients developed a second melanoma. In 11 patients (19%), a second melanoma was diagnosed more than 10 years after their first melanoma. Second melanomas more commonly had a lower mean tumour thickness than the first ones, but 8 out of 58 (13.8%) had a higher tumour thickness than their first melanoma. Skin phototype I-II, having more than 50 melanocytic nevi, and recurrent sunburns were associated with the development of a second melanoma. In multivariate analysis, skin phototype I-II (odds ratio [OR] = 5.41; p < 0.001) and a higher number of nevi (OR = 3.44; p < 0.001) remained as independent risk factors for the development of a second melanoma. CONCLUSIONS: Patients with fair skin phototype and more than 50 melanocytic nevi are at increased risk of developing a second primary melanoma and should be closely monitored throughout their lives to detect earlier additional melanomas.

Do not PASS any melanoma without diagnosis: a new simplified dermoscopic algorithm.

INTRODUCTION: Dermoscopic algorithms for melanoma diagnosis could be time-expending, and their reliability in daily practice lower than expected. OBJECTIVE: To propose a simplified dermoscopic algorithm for melanoma diagnosis. MATERIAL AND METHODS: A multicenter retrospective analysis of 1,120 dermoscopic images of atypical melanocytic tumors (320 melanomas and 800 non-melanomas) was performed. An algorithm based on polychromia, asymmetry in colors or structures, and some melanoma-specific structures was designed. Univariate and multivariate logistic regression analysis was calculated to estimate the coefficients of each potential predictor for melanoma diagnosis. A score was developed based on the dermoscopic evaluations performed by four experts blinded to histological diagnosis. RESULTS: Most melanomas had ≥3 colors (280; 84.5%), asymmetry in colors or structures (289; 90.3%), and at least one melanoma-specific structure (316; 98.7%). PASS score ≥3 had a 91.9% sensibility, 87% specificity, and 88.4% diagnostic accuracy for melanoma. PASS algorithm showed an area under the curve (AUC) of 0.947 (95% CI 0.935-0.959). LIMITATIONS: This study was retrospective. A comparison between the performances of different dermoscopic algorithms is difficult because of their designs. CONCLUSION: PASS algorithm showed a very good diagnostic accuracy, independently of the observers' experience, and it seems easier to perform than previous dermoscopic algorithms.

Melanocortin 1 receptor variants and their association with phenotypic characteristics and sporadic multiple primary melanomas in a cohort of 402 Spanish subjects.

The melanocortin 1 receptor (MC1R) gene is considered to be a major determinant of the risk of melanoma. The role of MC1R polymorphisms as predisposing factors for the development of a second primary melanoma is not well established. The present study analyses the characteristics from subjects with certain MC1R variants without any other genetic predisposition, as well as the risk of second primary melanoma associated with these variants. We performed a prospective longitudinal single-centre study based on follow-up information of 402 patients diagnosed with cutaneous melanoma. MC1R gene was sequenced in all subjects. High-risk variants were defined as those previously associated with melanoma (V60L, V92M, I155T, R160W, R163Q and D294H). 253 (63%) patients had at least one predisposing variant. These individuals had higher proportion of red/blonde hair, multiple primary melanomas and first melanoma diagnosis under the age of 60. Second primary melanomas were detected in 28 (3.8%) subjects. Having more than 25 melanocytic nevi was associated significantly to the development of second primary melanomas. A higher proportion of individuals carrying at least one predisposing MC1R variant develop a second melanoma, although statistical significance was not reached. Therefore, some MC1R polymorphisms might determine clinical and histological differences between patients with cutaneous melanoma and may represent a risk factor for second primary melanoma, although more studies are needed.

Digital melanoma in Caucasians: a descriptive and survival study according to sublocation.

BACKGROUND AND OBJECTIVES: Digital melanoma is an uncommon form of acral melanoma that is anatomically restricted to the finger. The aim of this study is to provide specific epidemiological and clinical information about this subtype of melanoma, as well as to identify differences in recurrence and survival depending on the anatomical sublocation. PATIENTS AND METHODS: We describe a group of 45 Caucasian patients with digital melanoma divided into three groups: nail unit melanoma (group A), finger skin melanoma (group B), and those melanomas that involve both nail and adjacent skin (group C). RESULTS: The mean tumor thickness was 4.66 mm, and the most common histological subtype is acral lentiginous melanoma. Group C was more frequent in older men and was thicker and more frequently ulcerated (P < 0.05). In addition, patients in group C developed distant metastases more frequently and had a significantly lower median disease-free survival (26.60 months) compared with group A (69.47 months) and group B (89.81 months) (P < 0.05). CONCLUSIONS: According to our results, digital melanoma limited to nail apparatus or finger skin was associated with a better prognosis, while those affecting both nail apparatus and skin showed lower melanoma-specific survival.

Activin A Sustains the Metastatic Phenotype of Tumor-Associated Macrophages and Is a Prognostic Marker in Human Cutaneous Melanoma.

Tumor cells attract and dynamically interact with monocytes/macrophages to subvert their differentiation into tumor-associated macrophages (TAMs), which mainly promote immune suppression and neoplastic progression, but the pathways and microenvironmental cues governing their protumoral deviation are not completely understood. To identify the molecular pathways responsible for TAM differentiation, we screened the biomarkers secreted during melanoma‒macrophage interactions using Quantibody microarrays and RNA sequencing of macrophages. We found that activin A, a member of the transforming GF family, plays an instrumental role in the cross-talk between melanoma cells and monocytes/macrophages, which results in the upregulation of distinct tumor-sustaining genes and the achievement of proinvasive and immunosuppressive functions of TAMs. Blockade of activin reduces the upregulation of part of these genes and prevents the acquisition of protumoral functions, facilitating human melanoma rejection by transferred human lymphocytes in a xenograft mouse model. Remarkably, screening of two independent cutaneous primary melanoma collections showed that activin A is enriched in TAMs and melanoma cells from patients with worse outcomes and constitutes a new and independent prognostic marker. Thus, we identify activin A as a key intermediary in the protumoral and immunosuppressive functions of TAMs, with significant potential as a disease biomarker as well as an immunotherapeutic target.

Dermal substitutes: an alternative for the reconstruction of large full-thickness defects in the plantar surface

Abstract Large defects in plantar surface secondary to acral melanoma excision can be difficult to repair with local flaps, and skin grafts in weight-bearing surfaces often suffer necrosis causing prolonged disability. Acellular dermal matrices represent an easy alternative to cover deep wounds or those with bone or tendon exposure. Despite their high cost and the requirement of two surgical procedures, this alternative may offer excellent functional and aesthetic results in acral defects.

Dermal substitutes: an alternative for the reconstruction of large full-thickness defects in the plantar surface.

Large defects in plantar surface secondary to acral melanoma excision can be difficult to repair with local flaps, and skin grafts in weight-bearing surfaces often suffer necrosis causing prolonged disability. Acellular dermal matrices represent an easy alternative to cover deep wounds or those with bone or tendon exposure. Despite their high cost and the requirement of two surgical procedures, this alternative may offer excellent functional and aesthetic results in acral defects.

CCL20/TNF/VEGFA Cytokine Secretory Phenotype of Tumor-Associated Macrophages Is a Negative Prognostic Factor in Cutaneous Melanoma.

TAMs constitute a large fraction of infiltrating immune cells in melanoma tissues, but their significance for clinical outcomes remains unclear. We explored diverse TAM parameters in clinically relevant primary cutaneous melanoma samples, including density, location, size, and polarization marker expression; in addition, because cytokine production is a hallmark of macrophages function, we measured CCL20, TNF, and VEGFA intracellular cytokines by single-cell multiparametric confocal microscopy. The Kaplan-Meier method was used to analyze correlation with melanoma-specific disease-free survival and overall survival. No significant correlations with clinical parameters were observed for TAM density, morphology, or location. Significantly, higher contents of the intracellular cytokines CCL20, TNF, and VEGFA were quantified in TAMs infiltrating metastasizing compared to non-metastasizing skin primary melanomas (p < 0.001). To mechanistically explore cytokine up-regulation, we performed in vitro studies with melanoma-conditioned macrophages, using RNA-seq to explore involved pathways and specific inhibitors. We show that p53 and NF-κB coregulate CCL20, TNF, and VEGFA in melanoma-conditioned macrophages. These results delineate a clinically relevant pro-oncogenic cytokine profile of TAMs with prognostic significance in primary melanomas and point to the combined therapeutic targeting of NF-kB/p53 pathways to control the deviation of TAMs in melanoma.

Dermoscopic Predictors of Tumor Thickness in Cutaneous Melanoma: A Retrospective Analysis of 245 Melanomas.

INTRODUCTION: The literature regarding the association of dermoscopic structures with Breslow thickness in melanoma is scarce, limited to small case series, and mostly outdated. OBJECTIVE: This study determined the dermoscopic patterns, colors and structures that are associated with melanoma in situ, thin melanomas (<0.8 mm) and thick melanomas potentially requiring sentinel lymph node biopsy according to current guidelines (≥0.8 mm). METHODS: A retrospective evaluation of 245 dermoscopic images of primary cutaneous melanoma located on the trunk or limbs was performed by consensus of 2 dermoscopists. RESULTS: Red-pink, blue-gray and white color, blue-white veil, shiny white streaks, irregular vessels, blue-black pigmentation, milky red areas, pseudolacunae, ulceration and rainbow pattern were associated with thickness ≥0.8 mm, whereas atypical pigmented network, regression and hypopigmented areas were significantly associated with early melanomas. LIMITATIONS: This is a retrospective study performed in a single institution. Melanomas of special sites were excluded from our evaluation. Dermoscopy is based on subjective evaluations that depend largely on the observers' experience. CONCLUSIONS: The identification of certain dermoscopic structures and colors might help in the discrimination between thin and thick melanomas.