The aryl hydrocarbon receptor AhR links atopic dermatitis and air pollution via induction of the neurotrophic factor artemin.

Atopic dermatitis is increasing worldwide in correlation with air pollution. Various organic components of pollutants activate the transcription factor AhR (aryl hydrocarbon receptor). Through the use of AhR-CA mice, whose keratinocytes express constitutively active AhR and that develop atopic-dermatitis-like phenotypes, we identified Artn as a keratinocyte-specific AhR target gene whose product (the neurotrophic factor artemin) was responsible for epidermal hyper-innervation that led to hypersensitivity to pruritus. The activation of AhR via air pollutants induced expression of artemin, alloknesis, epidermal hyper-innervation and inflammation. AhR activation and ARTN expression were positively correlated in the epidermis of patients with atopic dermatitis. Thus, AhR in keratinocytes senses environmental stimuli and elicits an atopic-dermatitis pathology. We propose a mechanism of air-pollution-induced atopic dermatitis via activation of AhR.

Efficacy and safety of TM5614 in combination with paclitaxel in the treatment of paclitaxel-resistant cutaneous angiosarcoma: Phase II study protocol.

Cutaneous angiosarcoma (CAS) is an endothelial cell-derived, highly aggressive type of vascular tumour. Although chemoradiotherapy with paclitaxel (PTX) is recognized as a first-line therapy for CAS, second-line therapy for CAS remains controversial, and there is no standard therapy for taxane-resistant CAS. Plasminogen activator inhibitor-1 (PAI-1) is associated with poor clinical outcomes, and elevated levels of PAI-1 in both tissue and serum are correlated with poor response to therapy in various cancers, including skin cancers. Since PAI-1 protects endothelial cells from Fas ligand-mediated apoptosis, PAI-1 inhibition might induce apoptosis of endothelial cell-derived tumours such as CAS. This is a single-arm, open-label, multi-institutional, Phase 2 clinical trial to assess the efficacy and safety of PTX in combination with TM5614 (PAI-1 inhibitor) in patients with PTX-resistant CAS. PTX will be administered for 28 weeks, with oral administration of TM5614. The primary endpoint of this study will be the overall response rate (ORR) at 28 weeks after starting treatment (central image evaluation). The secondary endpoint will include the ORR at 28 weeks after starting treatment (investigator evaluation), ORR at 8 weeks and 16 weeks after initiation of treatment (central and investigator evaluation), progression-free survival, overall survival, disease control rate and safety profiles. Assuming the null hypothesis of a response rate of 13.6% and an alternative hypothesis of 45%, a minimum of 15 patients are required to achieve a two-sided, Type I error of 5% and power of 70% based on the exact binomial distribution. Data quality control will be conducted by a combination of centralized (remote) and on-site monitoring. This study will contribute to the development of novel combination therapy for PTX-resistant CAS patients, which remains an unmet clinical need.

Possible effects of plasminogen activator inhibitor-1 on promoting angiogenesis through matrix metalloproteinase 9 in advanced mycosis fungoides.

Mycosis fungoides (MF) progresses slowly before advancing to skin tumors followed by lymph node and visceral involvement. Among MF progression, stage IIB is an initial time point of tumor formation in MF. Since MF in tumor stage possess abundant blood vessels, it is important to evaluate the pro-angiogenic factors before and after MF in stage IIB. In this report, we investigated pro-angiogenic soluble factors in MF patients, as well as its pro-angiogenetic effects on tumor cells and stroma cells. We first evaluated the serum levels of pro-angiogenic factors in 9 MF patients without tumor formation and 8 MF patients with tumor formation. Among them, the serum MMP-9 and plasminogen activator inhibitors 1 (PAI-1) was significantly increased in MF with tumor formation compared in MF without tumor formation, leading to favorable formation of human dermal microvascular endothelial cells tube networks. Moreover, PAI-1 stimulation significantly increased the mRNA expression and protein production MMP-9 on monocytes derived M2 macrophages and HUT-78. Furthermore, since MMP-9 production from tumor cells as well as stromal cells is suppressed by bexarotene, we evaluate the baseline serum pro-angiogenic factors including MMP-9 in 16 patients with advanced cutaneous T cell lymphoma treated with bexarotene. The serum levels of MMP-2 and MMP-9 was significantly increased in bexarotene non-responded patients compared to responded patients. Our present study suggested the significance of MMP-9 and PAI-1 for the progression of MF stage toward to the tumor stage, and could be a therapeutic target in future.

Phase II, multicenter study of plasminogen activator inhibitor-1 inhibitor (TM5614) plus nivolumab for treating anti-PD-1 antibody-refractory malignant melanoma: TM5614-MM trial.

BACKGROUND: Anti-programmed cell death 1 antibodies (anti-PD-1 Abs) are widely used for advanced melanoma, but the efficacy of an anti-PD-1 Abs is limited in the Asian population. There remains an unmet need to improve the therapeutic effects of anti-PD-1 Abs treatment, particularly in melanoma patients who are refractory to anti-PD-1 Abs. The aim was to evaluate anti-PD-1 Abs treatment in combination with TM5614 (plasminogen activator inhibitor-1: PAI-1 inhibitor) in patients with unresectable melanoma. METHODS: The TM5614-MM study was a multicentre, open-label, single-arm, phase 2 clinical trial to evaluate the efficacy and safety of nivolumab in combination with TM5614 in patients with advanced, unresectable malignant melanoma recruited at 7 Japanese institutes between 13 September 2021 and 31 March 2023. Patients with metastatic or unresectable melanoma previously treated with anti-PD-1 Abs were enrolled. Nivolumab 480 mg was administered intravenously every 4 weeks for 8 weeks, while TM5614 was administered orally at a dose of 120 mg (0-4 weeks) and 180 mg once daily (5-8 weeks). The primary endpoint was the overall response rate after 8 weeks of concomitant use of TM5614. RESULTS: Thirty nine patients were enrolled, and 34 patients in the anti-PD-1 Abs-refractory cohort. The overall response rate at 8 weeks was 25.9% (95% CI: 12.9-44.9%; P = .027) in 27 anti-PD-1-Abs refractory patients by investigator assessment in the protocol per set cohort. Seven patients discontinued treatment due to progressive disease or adverse events. Treatment-related grade 3 or higher adverse events occurred in 3 of 39 patients (7.7%) in the intention-to-treat cohort. CONCLUSIONS: TM5614 in combination with nivolumab is well-tolerated and effective in anti-PD-1 Abs-refractory, unresectable melanoma. TRIAL REGISTRATION: This trial was registered with Clinical Trial gov, jRCT2021210029.

Bexarotene-induced hypothyroidism and dyslipidemia; a nation-wide study.

Central hypothyroidism and dyslipidemia are well-known adverse events (AEs) of bexarotene therapy. Although hypothyroidism is known to cause dyslipidemia, no study has examined the association between hypothyroidism and dyslipidemia in patients undergoing bexarotene therapy. The aim of this study is to examine this association. A retrospective observational study was performed among 294 patients who initiated bexarotene therapy in Japan (nation-wide postmarketing complete surveillance). Jonckheere-Terpstra (one sided) test was performed to evaluate the effect of the bexarotene dose on lipid metabolisms, and regression analyses were performed to evaluate associations of bexarotene dose, free thyroxine (FT4), body mass index (BMI), and lipid metabolisms. Most patients developed hypothyroidism. Two-third of patients showed FT4 values below the lower limit at 1 week. Triglycerides (TG) increased in a bexarotene dose-dependent manner, and grade ≥3 AEs on hypertriglyceridemia was observed in 39% of the patients. Additionally, one-third of grade ≥3 AEs on hypertriglyceridemia occurred within 1 week. The delta_FT4 (difference in FT4 from baseline) negatively correlated with TG increase at 1 week (p = 0.012) but not with low density lipoprotein cholesterol (LDL-C) increase at any week. Bexarotene-induced hypothyroidism is almost inevitable and occurred quickly. Bexarotene-induced hypertriglyceridemia showed positive bexarotene dose dependency and negative delta_FT4 dependency. Prophylactic and appropriate thyroid hormone compensation therapy and starting bexarotene at low doses with subsequent titration while managing dyslipidemia may have a beneficial effect for the successful continuation of bexarotene therapy without severe endocrine and metabolic AEs.

Plasminogen activating inhibitor-1 promotes angiogenesis in cutaneous angiosarcomas.

Plasminogen activating inhibitor-1 (PAI-1) is associated with poor clinical outcomes, and elevated levels of PAI-1 in both tissue and serum are correlated with poor response to therapy in various cancers, including skin cancer. Cutaneous angiosarcoma (CAS) is a vascular tumor histologically characterized by detachment of endothelial cell-derived tumor cells. Since CAS expresses multiple angiogenic growth factors and has increased expressions of angiogenic receptor tyrosine kinase transcripts including VEGFR1/2/3, angiogenesis-promoting factors are potential drug targets in CAS. In this study, the expression of PAI-1 was examined in 31 cases of CAS, and the immunomodulatory effects of PAI-1 on a human CAS cell line, ISO-HAS-B, were evaluated. We found that, of the angiogenesis-promoting factors, PAI-1 was expressed in almost all cases of CAS, and PAI-1 increased the mRNA expressions of IL-23p19, VEGF-C, CXCL5 and CCL20 on ISO-HAS-B. Moreover, PAI-1 stimulated ISO-HAS-B culture supernatant promoted favourable tube networks, suggesting that these tumor-derived factors promote the pro-angiogenic effect on tumor development. In addition, IL-23p19 was expressed in 61.3% of cases, whereas VEGF-C was expressed in 41% of cases. The results of the present study suggest that PAI-1 promotes angiogenesis that results in tumor progression in CAS.

The Antimicrobial Peptide Cathelicidin Exerts Immunomodulatory Effects via Scavenger Receptors.

An active form of cathelicidin antimicrobial peptide, LL-37, has immunomodulatory and stimulatory effects, though the specific pathways are not clear. The purpose of this study was to identify the cellular pathways by which LL-37 amplifies the inflammation induced by damage-associated molecular patterns (DAMPs). We performed DNA microarray, reverse transcription polymerase chain reaction, immunoblotting, and proximity ligation assays using cultured keratinocytes treated with LL-37 and/or the DAMP poly(I:C), a synthetic double-stranded RNA. In contrast to the combination of LL-37 and poly(I:C), LL-37 alone induced genes related to biological metabolic processes such as VEGFA and PTGS2 (COX-2). Inhibition of FPR2, a known receptor for cathelicidin, partially suppressed the induction of VEGFA and PTGS2. Importantly, VEGFA and PTGS2 induced by LL-37 alone were diminished by the knockdown of scavenger receptors including SCARB1 (SR-B1), OLR1 (SR-E1), and AGER (SR-J1). Moreover, LL-37 alone, as well as the combination of LL-37 and poly(I:C), showed proximity to the scavenger receptors, indicating that LL-37 acts via scavenger receptors and intermediates between them and poly(I:C). These results showed that the broad function of cathelicidin is generally dependent on scavenger receptors. Therefore, inhibitors of scavenger receptors or non-functional mock cathelicidin peptides may serve as new anti-inflammatory and immunosuppressive agents.

Successful treatment of metastatic fibrosarcomatous dermatofibrosarcoma protuberans with imatinib mesylate.

Dermatofibrosarcoma protuberans (DFSP) is a fibrohistiocytic tumor characterized by a high risk of local recurrence but a low risk of metastasis. A small subpopulation of DFSP undergoes fibrosarcomatous (FS) change, and approximately 15%-57% of cases of DFSP with FS change metastasizes, leading to a poor prognosis. In this report, a case of metastatic FS-DFSP that was successfully treated with imatinib mesylate in which the IHC staining pattern of recurrent DFSP was quantitatively analyzed in primary and metastatic DFSP areas, is described. Importantly, the recurrent area was composed of two IHC staining patterns (CD34low PD-L1high Ki67high , and CD34high PD-L1low Ki67low pattern), while the metastatic area showed a clonal pattern (CD34high PD-L1low Ki67intermediate ) in the present case. In this report, we described a case of metastatic fibrosarcomatous DFSP successfully treated with imatinib mesylate. This case suggests a subpopulation of DFSP with a favorable metastatic pattern.

Cutaneous T cell lymphoma treated with mogamulizumab monotherapy and mogamulizumab plus etoposide combined therapy: A real-world case series.

Since the efficacy of mogamulizumab has been confirmed by a phase III, randomized study, mogamulizumab is one of the promising first-line therapies for advanced cutaneous T cell lymphoma (CTCL), though its efficacy is not completely satisfactory. Therefore, several anti-lymphoma drugs such as etoposide were recently used to enhance the anti-tumor effects of mogamulizumab for the treatment of mycosis fungoides (MF). In this report, the anti-tumor effects of mogamulizumab and post mogamulizumab therapy were retrospectively evaluated in 11 cases of CTCL in real-world clinical practice. The best response rate (RR) was 45.5% (95% confidence interval [CI], 21.3%-72.0%) for the total cohort, 50.0% (95%CI, 21.5%-78.5%) for the MF cohort, and 33.3% (95%CI, 5.6%-79.8%) for the primary cutaneous peripheral T cell lymphoma not otherwise specified (PCPTCL-NOS) cohort. The objective response rate (ORR) at 1 month (ORR1) for the total cohort was 45.5% (95%CI, 21.3%-72.0%), and ORR at 4 months (ORR4) was 27.3% (95%CI, 9.2%-57.1%). The mean time to next treatment (TTNT) was 16.0 weeks (3-100 weeks) for all patients, 16.5 months (3-100 weeks) for the MF cohort, and 9.0 (7-16) weeks for the PCPTCL-NOS cohort. The efficacy rate of etoposide-based therapy was 71.4% (95%CI, 35.9%-98.0%) for all patients, 80% (95%CI, 35.9%-98.0%) in the MF cohort, and 50% (95%CI, 9.5%-90.5%) in the PCPTCL-NOS cohort. The median duration of response was 182 (45-323) weeks. The safety profile of mogamulizumab monotherapy in the present cohort was comparable to the previous phase III, randomized trial. The present study suggests that the efficacy and safety profiles of mogamulizumab monotherapy as second-line therapy and beyond in a real-world Japanese cohort were comparable to those in the previous phase III, randomized trial.

Adjuvant Anti-PD-1 Antibody Therapy for Advanced Melanoma: A Multicentre Study of 78 Japanese Cases.

Anti-PD-1 antibodies (Abs) are among the optimal adjuvant therapies for melanoma at high risk of recurrence, especially BRAF wild-type melanoma, but the anti-tumour effects of anti-PD-1 Abs in the adjuvant setting for acral melanoma have not been evaluated previously. The aim of this study was to analyse the efficacy and safety profiles of anti-PD-1 Ab monotherapy in the adjuvant setting in an Asian population including a high ratio of acral melanoma. The efficacy and safety profiles of anti-PD-1 Ab monotherapy in the adjuvant setting were retrospectively analysed in 78 Japanese patients with advanced melanoma, including 31 cases (40%) of acral melanoma. Overall relapse-free survival was 60.3% (47 of 78 cases, 95% confidence interval (CI) 49.2-70.4%), and 39.7% of patients (31 of 78 patients, 95% CI 29.6-50.8%) relapsed during the adjuvant PD-1 Ab treatment. Six cases (7.9%) discontinued the protocol due to serious adverse events. One case (1.3%) discontinued the protocol due to trauma. The relapse-free survival of acral melanoma was 25.8%, whereas that of high cumulative sun damage was 60.0%, and that of low cumulative sun damage was 57.1%. The acral type had a significantly lower 12-month relapse-free survival than other cutaneous types (p = 0.029). The acral type appeared to be an independent prognostic factor on multivariate analysis (p = 0.015). Adverse events due to anti-PD-1 antibody were observed in 37.1% overall. The results of this study suggest that anti-PD-1 Ab therapy in the adjuvant setting is less effective for acral melanoma than for other cutaneous types.

Stromal Factors as a Target for Immunotherapy in Melanoma and Non-Melanoma Skin Cancers.

Immune checkpoint inhibitors (ICIs), such as anti-programmed cell death 1 (PD1) antibodies (Abs) and anti-cytotoxic T-lymphocyte associated protein 4 (CTLA4) Abs, have been widely administered for not only advanced melanoma, but also various non-melanoma skin cancers. Since profiles of tumor-infiltrating leukocytes (TILs) play important roles in immunotherapy using ICIs, it is important to evaluate cancer stromal cells such as tumor-associated macrophages (TAMs) and cancer-associated fibroblasts (CAFs), as well as stromal extracellular matrix protein, to predict the efficacy of ICIs. This review article focuses particularly on TAMs and related factors. Among TILs, TAMs and their related factors could be the optimal biomarkers for immunotherapy such as anti-PD1 Ab therapy. According to the studies presented, TAM-targeting therapies for advanced melanoma and non-melanoma skin cancer will develop in the future.

Immunotherapy for Melanoma: The Significance of Immune Checkpoint Inhibitors for the Treatment of Advanced Melanoma.

Therapeutic options for treating advanced melanoma have progressed rapidly in recent decades. Until 6 years ago, the regimen for treating advanced melanoma consisted mainly of cytotoxic agents such as dacarbazine and type I interferons. Since 2014, anti-programmed cell death 1 (PD1) antibodies have been recognized as anchor drugs for treating advanced melanoma, with or without additional combination drugs such as ipilimumab, but the efficacies of these immunotherapies are not fully satisfactory. In this review, we describe the development of the currently available anti-PD1 Abs-based immunotherapies for advanced melanoma, focusing on their efficacy and immune-related adverse events (AEs), as well as clinical trials still ongoing for the future treatment of advanced melanoma.

Serum soluble CD163 and proinflammatory chemokines may be biomarkers of the onset of adverse events in dabrafenib plus trametinib combination therapy for advanced melanoma.

Various adverse events (AEs) have been reported to occur at a high rate in patients treated with dabrafenib plus trametinib (D + T) combination therapy. Among such AEs, the incidence of pyrexia was highest among the series of AEs in patients treated with D + T combination therapy. Although little is known about the mechanisms of pyrexia caused by D + T combination therapy, a recent report suggested that sCD163, as well as interferon-inducible chemokines (CXCL9, CXCL10, CXCL11), might correlate with pyrexia caused by encorafenib plus binimetinib combination therapy. In addition to these soluble factors, CXCL5 is a biomarker for predicting immune-related AEs in melanoma patients treated with nivolumab. From the above findings, we hypothesized that these soluble factors might also correlate with the onset of AEs in D + T combination therapy. The serum levels of sCD163 were increased in patients with pyrexia in parallel with their severity, whereas the serum levels of CXCL5 were increased in patients without pyrexia. Moreover, increased levels of CXCL9, CXCL10, and CXCL11 were prominent in patients with AEs over G2 levels. As these chemokines recruit Th1, Th17, and activated CD8+ T cells, increased serum levels of these chemokines might correlate with the positive feedback of inflammatory reactions related to AEs.

RB1 gene mutations are a distinct predictive factor in Merkel cell carcinoma.

Merkel cell carcinoma (MCC) is a rare cutaneous neuroendocrine carcinoma that tends to show local recurrence and metastasis. Typically, MCC is polyomavirus (MCPyV)-associated and cytokeratin 20 (CK20) positive. However, little is known about this tumor and its origins. Here, we aimed to determine the developmental origins of MCC and to identify prognostic clinicopathologic factors. Initial examinations revealed that CK20 and MCPyV expression (CK20+, MCPyV+ (60%); CK20+, MCPyV- (10%); CK20-, and MCPyV- (30%)) did not affect overall survival. With RB1 gene sequencing of FFPE specimens, which covered an entire exon, all RB1 mutation-positive cases showed positive regional lymph node and/or distant metastases (8/8 cases, 100%), whereas the frequency of the metastasis was statistically significantly lower in RB1 mutation-negative cases, (10/16 cases, 62%, P = 0.033). The results were also confirmed with immunohistochemistry, and either RB1 alterations, entire exon sequencing, or immunohistochemistry was associated with the metastasis (P = 0.007). RB1 alterations may be used to access the aggressive clinical course of MCC.

Serum CCL22 levels decreased in parallel with disease activity in CCR4-positive mycosis fungoides treated with mogamulizumab.

Mogamulizumab is a humanized anti-C-C chemokine receptor type (CCR)4 antibody that shows cytotoxicity against CCR4+ lymphoma cells via antibody-dependent cell-mediated cytotoxicity in advanced cutaneous T cell lymphoma (CTCL) patients. The production levels of ligands for CCR4, that is, Chemokine (C-C motif) ligand (CCL)17 and CCL22, are important for the assessment of the disease activity in CTCL patients. We evaluated the serum levels of CCL17, CCL19, CCL22, C-X-C motif chemokine ligand (CXCL)10, and CXCL13, which are ligands for CCR4, CCR7, CCR4, C-X-C Motif Chemokine Receptor (CXCR)3, and CXCR5, respectively, at baseline and 4 weeks after the administration of mogamulizumab in five patients with mycosis fungoides. The serum levels of CCL22 were significantly decreased in patients who responded to mogamulizumab, but no differences were identified in the serum levels of CCL17, CCL19, CXCL10, or CXCL13. Immunofluorescence staining revealed that the majority of CCL22-producing cells were cluster of differentiation (CD)163+ tumor-associated macrophages, and they were surrounded by CCR4+ CTCL cells. Our present data suggested that the serum CCL22 level may be a predictive marker of the efficacy of mogamulizumab for the treatment of CCR4+ CTCL.

Successful treatment of mogamulizumab-resistant mycosis fungoides with mogamulizumab plus etoposide combined therapy: Investigation of the immunomodulatory effects of etoposide on the tumor microenvironment.

Mogamulizumab shows cytotoxicity against CCR4+ lymphoma cells by antibody-dependent cell-mediated cytotoxicity (ADCC) in advanced cutaneous T-cell lymphoma (CTCL) patients. Although mogamulizumab is used as one of the anchor drugs for the treatment of advanced CTCL, its efficacy is unsatisfactory, especially in mycosis fungoides (MF). Therefore, additional drugs to enhance the antitumor effects of mogamulizumab are needed to further optimize its use for the treatment of MF. In this report, two cases of mogamulizumab-resistant MF successfully treated with additional administration of etoposide are presented. Moreover, the possible mechanisms of mogamulizumab-etoposide combined therapy for the treatment of MF were investigated based on the modulation of chemokine profiles in vivo using an EL-4 mouse T-cell lymphoma model. Intraperitoneal administration of etoposide significantly increased the mRNA expressions of CCL17, CXCL5, and CXCL10, suggesting that CCR4+ CTCL cells gather around the tumor-associated macrophagess. Furthermore, the immunomodulatory effects of etoposide on the mRNA expressions of these chemokines were validated using monocyte-derived M2 macrophages in vitro. Since mogamulizumab shows cytotoxicity against CCR4+ lymphoma cells by ADCC that depends on the contact between the lymphoma cells and the effector cells, these chemokines could enhance the therapeutic effect of mogamulizumab.

Successful treatment of unresectable recurrent cutaneous squamous cell carcinoma of the scalp with meningeal invasion with nivolumab monotherapy.

Although the number of cutaneous squamous cell carcinoma (cSCC) cases is increasing, the effectiveness of systemic therapy for the treatment of advanced cSCC is limited. Since cSCC possesses a high tumor mutation burden (TMB) compared to other cancer species, and since high TMB correlated with increased neoantigens and the efficacy of anti-PD1 antibodies (Abs) in various cancers, cSCC could be a target for anti-PD1 Abs monotherapy. In this report, we describe a case of unresectable recurrent cSCC of the scalp with meningeal invasion, but highly expressed programmed death-ligand 1 (PD-L1), treated with nivolumab monotherapy.

Variable indoleamine 2,3-dioxygenase expression in acral/mucosal melanoma and its possible link to immunotherapy.

Immune checkpoint inhibitors have improved the prognosis of advanced melanoma. Although anti-programmed death ligand-1 (PD-L1) is a well-studied biomarker for response to anti-programmed death-1 PD-1 therapy in melanoma, its clinical relevance remains unclear. It has been established that the high expression of indoleamine 2,3-dioxygenase (IDO) is correlated to a response to anti-CTLA-4 treatment in melanoma. However, it is still unknown whether the IDO expression is associated with response to anti-PD-1 therapy in advanced melanoma. In addition, acral and mucosal melanomas, which comprise a great proportion of all melanomas in Asians, are genetically different subtypes from cutaneous melanomas; however, they have not been independently analyzed due to their low frequency in Western countries. To evaluate the association of IDO and PD-L1 expression with response to anti-PD-1 antibody in acral and mucosal melanoma patients, we analyzed 32 Japanese patients with acral and mucosal melanomas treated with anti-PD-1 antibody from the perspective of IDO and PD-L1 expression levels by immunohistochemistry (IHC). Multivariate Cox regression models showed that the low expression of IDO in tumors was associated with poor progression-free survival (HR = 0.33, 95% CI = 0.13-0.81, P = 0.016), whereas PD-L1 expression on tumors was not associated with progression-free survival. Significantly lower expression of IDO in tumors was found in non-responders compared to responders. Assessment of the IDO expression could be useful for the identification of suitable candidates for anti-PD-1 therapy among acral and mucosal melanomas patients. Further validation study is needed to estimate the clinical utility of our findings.

Malassezia-derived aryl hydrocarbon receptor ligands enhance the CCL20/Th17/soluble CD163 pathogenic axis in extra-mammary Paget's disease.

Malassezia yeast play a role in the pathogenesis of chronic dermatitis, especially in apocrine areas, by polarizing the local immunologic background to a Th2/Th17 state through aryl hydrocarbon receptor (AhR)-dependent pathways. Extra-mammary Paget's disease (EMPD) is an adenocarcinoma of apocrine origin, and except for cases associated with Malassezia yeast and their metabolites, the lesions typically develop in areas not exposed to environmental material. The purpose of this study was to investigate (a) the immunomodulatory effects of Malassezia metabolites on normal human keratinocytes (NHKCs), focusing on interleukin (IL)-17 and related cytokines/chemokines (IL-23, IL-36γ, CCL20), (b) the expression of these factors in lesion-affected skin in EMPD and (c) the activation of tumor-associated macrophages (TAMs) by these factors. Malassezia metabolites augmented the expression of cytochrome P450, family 1, subfamily A, polypeptide 1 (CYP1A1), CCL20 and IL-36γ mRNA in NHKCs in vitro. In lesion-affected skin of patients with EMPD, epidermal keratinocytes expressed CYP1A1 and CCL20. In addition, Paget cells expressed CCL20 and IL-23. IL-17-producing cells were distributed adjacent to Paget cells. Compared to healthy donors, patients with EMPD exhibited significantly increased serum levels of soluble (s)CD163, CXCL5, CXCL10 and CCL20. In addition, serum levels of sCD163 decreased significantly following tumor resection. Our study demonstrates a possible mechanism for the development of EMPD involving AhR-mediated signalling by epidermal keratinocytes and RANKL-induced recruitment of Th17 cells and TAMs.

A novel technique to diagnose non-melanoma skin cancer by thermal conductivity measurements: Correlations with cancer stromal factors.

The skin surface temperature reflects the physiological state of the human body. Quantitative methods of identification of skin cancers based on accurate measurement of effective thermal conductivity (ETC) are among the promising diagnostic tools for differentiating non-invasive and invasive melanomas before surgical treatment. To validate these findings, in this report, the diagnostic methods for invasive and non-invasive extramammary Paget's disease (EMPD) and squamous cell carcinoma (SCC) were further tested by measuring the absolute value of skin surface temperature and the ETC of the skin. In addition, to investigate the stromal factors that might affect ETC, immunohistochemical staining for LL37, periostin (POSTN), MMP12, and MMP28 was performed. The invasive SCC and EMPD group showed a relatively higher skin surface temperature compared to the in situ SCC group. The non-invasive EMPD and SCC group showed significantly lower values of ETC at lesions, whereas the invasive EMPD group showed significantly higher ETC values at lesions compared to healthy skin. Immunohistochemical staining showed that the percentage of LL37-producing cells was significantly increased in invasive EMPD and SCC compared to that in non-invasive EMPD and SCC. Moreover, Spearman's rank correlation test showed a significant inverse correlation between the percentage of MMP12-positive cells and increased levels of ETC-expressing areas in EMPD and SCC (r = -.5997). The present study suggested that differences in ETC could be a novel high-accuracy diagnostic technique for non-melanoma skin cancer, especially for detecting dermal invasion of SCC and EMPD.