Genomic landscape of circulating tumour DNA in metastatic extramammary Paget's disease.

Although cancer personalized profiling by deep sequencing (CAPP-Seq) of cell-free DNA (cfDNA) has gained attention, the clinical utility of circulating tumour DNA (ctDNA) in extramammary Paget's disease (EMPD) has not been investigated. In this study, genomic alterations in the cfDNA and tumour tissue DNA were investigated in seven patients with metastatic EMPD. CAPP-Seq revealed mutations in 18 genes, 11 of which have not yet been reported in EMPD. The variant allele frequency of some of the mutated genes reflected the disease course in patients with EMPD. In one patient, the mutation was detected even though imaging findings revealed no metastasis. In another patient with triple EMPD (genital area and both axilla), cfDNA sequencing detected the mutation in a rib metastatic lesion, which was also detected in both axilla lesions but not the genital region. Investigations of the ctDNA may be useful towards the elucidation of clonal evolution in EMPD.

Overexpression of Janus kinase 2 protein in extramammary Paget's disease.

Extramammary Paget's disease is a rare malignant tumor of the skin that occurs primarily in the genitocrural region. Although the prognosis of extramammary Paget's disease with distant metastasis is poor, an effective therapy has not been established. Because Janus kinase 2 has attracted attention as a therapeutic target in several cancers, we investigated the expression of the Janus kinase 2 protein and the relationship between its level of expression and clinical significance in 53 patients with extramammary Paget's disease in our hospital. Immunohistochemistry showed that most extramammary Paget's disease tissues were positive for Janus kinase 2 (50/53, 94.3%), and the immunostaining intensity of Janus kinase 2 was correlated with the degree of invasiveness, lymph node metastasis and distant metastasis. Based on these findings, Janus kinase 2 may be a promising therapeutic target in extramammary Paget's disease.

Immunotherapy with 4-1BBL-Expressing iPS Cell-Derived Myeloid Lines Amplifies Antigen-Specific T Cell Infiltration in Advanced Melanoma.

We have established an immune cell therapy with immortalized induced pluripotent stem-cell-derived myeloid lines (iPS-ML). The benefits of using iPS-ML are the infinite proliferative capacity and ease of genetic modification. In this study, we introduced 4-1BBL gene to iPS-ML (iPS-ML-41BBL). The analysis of the cell-surface molecules showed that the expression of CD86 was upregulated in iPS-ML-41BBL more than that in control iPS-ML. Cytokine array analysis was performed using supernatants of the spleen cells that were cocultured with iPS-ML or iPS-ML-41BBL. Multiple cytokines that are beneficial to cancer immunotherapy were upregulated. Peritoneal injections of iPS-ML-41BBL inhibited tumor growth of peritoneally disseminated mouse melanoma and prolonged survival of mice compared to that of iPS-ML. Furthermore, the numbers of antigen-specific CD8+ T cells were significantly increased in the spleen and tumor tissues treated with epitope peptide-pulsed iPS-ML-41BBL compared to those treated with control iPS-ML. The number of CXCR6-positive T cells were increased in the tumor tissues after treatment with iPS-ML-41BBL compared to that with control iPS-ML. These results suggest that iPS-ML-41BBL could activate antigen-specific T cells and promote their infiltration into the tumor tissues. Thus, iPS-ML-41BBL may be a candidate for future immune cell therapy aiming to change immunological "cold tumor" to "hot tumor".

Myasthenic crisis and polymyositis induced by one dose of nivolumab.

An 80-year-old man, who developed multiple lymph node and skin metastasis of malignant melanoma, received nivolumab monotherapy. Two weeks after the first dose, he experienced anorexia and fatigue, and suffered from progressive, severe dyspnea and muscle weakness. We diagnosed him with myocarditis, myositis, and myasthenic crisis induced by nivolumab. We commenced steroid therapy, immune absorption therapy, plasma exchange therapy, and i.v. immunoglobulin therapy, and succeeded in saving his life. Because his serum level of anti-acetylcholine receptor antibodies in a sample collected before nivolumab treatment were positive and were elevated significantly after nivolumab, we suspected that nivolumab triggered a severe autoimmune response, which progressed subclinical myasthenia gravis to myasthenic crisis. We carried out T cell receptor repertoire analysis using next-generation sequencing technologies and identified infiltration of clonally expanded T cell populations in the skeletal muscle after nivolumab treatment, implying a very strong T cell immune response against muscular cells. To avoid severe immune-related adverse events, the exclusion of patients with subclinical autoimmune disease is very important for treatment with immune checkpoint inhibitors.

The proportion of lymphocytic inflammation with CD123-positive cells in lupus erythematous profundus predict a clinical response to treatment.

Lupus erythematosus profundus is a rare inflammatory disorder of subcutaneous fat in patients with lupus ery-thematosus. Previous reports suggested that plasmacytoid dendritic cells, which expressed CD123 and CD303 antigens, play a central proinflammatory role in the patho-genesis of lupus erythematosus. To find the factors that determine the response to treatment, we analysed 23 skin specimens from the patients with lupus erythematosus profundus. The patients with considerable lymphocytic inflammation with high percentages of CD123+ cells in dermis and subcutaneous fat significantly responded to the systemic corticosteroid therapies. On the other hand, the patients with minor lymphocytic inflammation with low percentages of CD123+ cells showed poor response to treatments. The mean percentage of CD123+ cells in patients who showed good response to therapy was significantly higher than those that showed poor response (p = 0.027). These results suggest that the clinical response to treatment of lupus erythematosus profundus could be predicted from the histological features.

SLC39A7 upregulation links to skin fibrosis in systemic sclerosis via TGF-ß/SMAD pathway.

Systemic sclerosis (SSc) is a multisystem connective tissue disease. Skin fibrosis, the hallmark of this disease, is defined as the excess deposition and accumulation of extracellular matrix, mainly type 1 collagen, in the dermis. SLC39A7 is an intracellular zinc transporter that plays a unique role in connective tissue formation. Therefore, we investigated the expression and role of SLC39A7 in SSc. Using immunohistochemical staining we demonstrated the overexpression of SLC39A7 in the skin of SSc patients. Quantitative real-time PCR and western blot data analysis showed that both SLC39A7 mRNA and protein levels were significantly upregulated in dermal fibroblasts from SSc patients compared to healthy controls. We used the shRNA lentiviral particle transduction system to stably knockdown the expression of SLC39A7 in SSc fibroblasts. The results showed that knockdown of SLC39A7 suppressed the production of type 1 collagen. These findings provide evidence that SLC39A7 is involved in the pathogenesis of SSc and that SLC39A7 plays a positive role in its progression.

Elevation of circulating DNAs of disease-associated cytokines in serum cell-free DNA from patients with alopecia areata.

Alopecia areata (AA) is an autoimmune disease characterized by damage to hair follicles and hair loss. Cell-free DNA (cfDNA) has recently received attention as a biomarker of various disorders including inflammatory skin diseases. In this study, we aimed to investigate the clinical significance of cfDNA and the circulating DNAs of disease-associated cytokines in AA patients. Serum samples were obtained from 63 patients with AA and 32 healthy controls (HC). Using droplet digital polymerase chain reaction, circulating C-X-C motif chemokine ligand (CXCL) 9, CXCL10, CXCL11, C-X-C motif chemokine receptor 3, interferon (IFN)-γ, interleukin (IL) -7, IL-15, and Janus kinase (JAK) 2 were detectable in both HC and AA patients. Among the detectable DNAs, copies of circulating CXCL9, CXCL11, IL-15, IFN-γ, and JAK2 were significantly higher in AA patients than in HC. These results suggest that increased circulating DNA levels may reflect damage to hair follicles in AA patients.

Genetic intratumour heterogeneity and clonal evolution in extramammary Paget's disease.

All tumour cells in a patient have shared and non-shared genetic alterations, and the diversity of mutations is described as intratumoural heterogeneity (ITH). Multiregion sequencing is a genome sequencing analytical technique used for multiple, spatially-separated biopsy tissues that may further our understanding of ITH and tumour evolution. Although genetic mutations in extramammary Paget's disease (EMPD) have recently been detected by next-generation sequencing analysis, there have been no reports of ITH based on multiregion sequencing in EMPD. Thus, we clarified the landscape of ITH and tumour evolution in EMPD. We performed whole-exome sequencing on 35 tissues (30 tumour tissues and five normal skin samples as a paired control), collected from five patients with EMPD. The rate of private mutations was significantly higher than that of ubiquitous and shared mutations. Ubiquitous mutations were not present in driver genes, and most driver genes exhibited private and shared mutations. The most frequent base substitution was C>T in almost all lesions, and most mutational signatures corresponded to signature 1, 2, 3, and 8. The types of proposed aetiology in most lesions were based on age and AID/APOBEC family and BRCA1/BRCA2 mutations. Evolutionary trees were characterized by short trunks and long branches due to the extremely high ratio of private mutations. In contrast, pathogenic factors, such as base substitutions, mutational signatures, and proposed aetiology, were shared. Tumour evolution in EMPD appears to be characterized by a high level of genetic ITH with shared background factors.

Serum levels of leptin receptor in patients with malignant melanoma as a new tumor marker.

Leptin is known to be abnormally expressed in a variety of cancers, and leptin receptors have been reported to be expressed on human melanoma cells. In this study, we evaluated the possibility that the serum levels of leptin receptor could be a tumor marker of malignant melanoma (MM). Serum samples were obtained from 71 patients with MM, and the serum levels of leptin receptor were measured by double-determinant ELISA. Interestingly, serum levels of leptin receptor decreased gradually with the stages of MM, being highest at in situ and lowest at stage IV. There was also a trend of reverse correlation between tumor thickness and serum levels of leptin receptor. To our knowledge, this is the first report investigating the serum levels of leptin receptor in MM, and serum leptin receptor levels may be used as a useful tumor marker of MM.

A study of 95 infantile hemangiomas treated with propranolol: A potentially efficacious combination with laser therapy.

We studied 95 patients with infantile hemangioma (IH) treated with propranolol at the Department of Dermatology, Kumamoto University Hospital, from November 2016 to January 2022, based on sex, site, clinical classification, duration of treatment, and residual lesions after treatment. Four of the 95 patients discontinued propranolol due to side effects, and 55 completed follow-ups at our hospital. We observed that 30.1% showed complete resolution of the skin rash, while the remaining 69.8% had erythema or atrophic scarring. Complete resolution occurred in 70% of the cases with the subcutaneous type but only in 15% with the tumor type. Seventeen of the 55 patients who completed follow-ups were treated with propranolol combined with laser therapy. Combined use of propranolol and laser therapy significantly reduced severe erythema compared to the propranolol monotherapy. These results suggest that propranolol therapy in IH often leaves erythema except in the subcutaneous type and that an improvement in erythema can be expected when propranolol is combined with laser therapy.

PIK3CA mutations in cutaneous squamous cell carcinoma.

Oncogenic PIK3CA mutation activates phosphoinositide 3-kinase (PI3K) enzyme, and PI3K-AKT signaling activation induces several growth-regulatory transcription factors. PIK3CA mutations have attracted attention as biomarker in clinical trials of various inhibitors including PI3K inhibitors. About 80% of PIK3CA mutations in human cancers are observed in 'hot spot' regions: exon 9 (E542K and E545K) and exon 20 (H1047R). There were few reports about clinical significance of PIK3CA mutations in cutaneous cell carcinoma (cSCC). Thus, we investigate the prevalence of three PIK3CA hot spot mutations in 143 cases with cSCC and evaluate the correlation between the presence of these mutations and clinical characteristics by using ddPCR. The frequency of each E542K, E545K and H1047R PIK3CA mutations was 1.4% (2/143), 2.8% (4/143), and 0.7% (1/143) respectively. No significant correlation was found between PIK3CA mutations and clinical characteristics. Although additional basic researches and clinical trials are necessary, various inhibitors may be effective therapeutics for PIK3CA mutation-positive cSCC. Our study revealed the prevalence of PIK3CA mutations in cSCC.

Overexpression of heat shock protein 90 through the downregulation of miR-9-5p in extramammary Paget's disease.

Heat shock protein 90 (HSP90) facilitates diverse cellular processes by interacting process with more than 200 client proteins. Overexpression of HSP90 contributes to the pathogenesis of various malignant tumors, and HSP90 inhibitors attenuate the progression of malignant tumors in vitro/vivo. Numerous clinical trials have used HSP90 inhibitors to treat several cancers, and pimitespib (an HSP90 inhibitor) is covered by insurance for advanced gastrointestinal stromal tumor in Japan. In this study, we investigated the expression pattern of HSP90 and analyzed its clinical significance in extramammary Paget's disease (EMPD). All 77 EMPD tissues investigated were positive for HSP90 expression. The immunoreactivity of HSP90 in fetal cases due to EMPD tended to be highly stained. Although there was no significant difference in HSP90 mRNA levels between 24 paired lesional and nonlesional tissues, microRNA-inhibiting HSP90 levels in tumor tissues were significantly decreased compared with those in normal tissues. Thus, HSP90 may play an important role in the pathogenesis of EMPD and may be a novel therapeutic target for EMPD.

The role of angiopoietin-like protein 2 in pathogenesis of dermatomyositis.

Dermatomyositis (DM) is an autoimmune disease marked by chronic inflammation of skin and muscle tissues and characterized clinically by proximal muscle weakness and skin eruption, including heliotrope rash, and Gottron's sign. Treatment with a non-specific immunosuppressive agent or anti-inflammatory corticosteroids is beneficial, although some patients are resistant to these therapies. Proinflammatory cytokines derived from infiltrating inflammatory cells and activated resident cells within skin and muscle tissues likely promote chronic inflammation in DM pathogenesis; however, molecular mechanisms underlying the disease are not completely defined. Here we show that mRNA and protein levels of angiopoietin-like protein 2 (Angptl2), a recently identified chronic inflammation mediator, are abundant in keratinocytes from DM patients' skin eruptions. To examine whether skin cell-derived Angptl2 promotes DM manifestations, we analyzed transgenic (Tg) mice expressing Angptl2 driven by the keratinocyte specific promoter K14 (K14-Angptl2) and therefore constitutively expressing Angptl2 in skin tissue. We found that K14-Angptl2 Tg mice exhibited skin phenotypes similar to those observed in DM patients. In addition, treatment of keratinocytes with exogenous Angptl2 activated the NF-κB inflammatory cascade, resulting in increased expression of the proinflammatory cytokines IL-1ß and IL-6. We propose that keratinocyte-derived Angptl2 functions in DM pathogenesis by inducing chronic inflammation in skin tissue.

Analysis of microsatellite instability using Promega panel in dermatofibrosarcoma protuberans.

Dermatofibrosarcoma protuberans (DFSP) is a rare neoplasm derived from fibroblasts. Although the frequency of microsatellite instability (MSI) in skin cancer is reported to be less than 5%, there is only one report of the status of MMR in DFSP. The only analytical report of microsatellite stability in which Promega panel is not used, showed that the frequency of MSI-high, MSI-low and microsatellite stable (MSS) cases was 13.9% (5/36), 16.7% (6/36) and 69.4% (25/36), respectively. Thus, the aim of this study was to evaluate the status of MMR in 36 patients with DFSP diagnosed at Kumamoto University. MSI analysis using the Promega panel showed that all cases were MSS, which indicated the absence of MSI in DFSP. This result indicates that the status of MMR may not be useful for the potential therapeutic application of pembrolizumab and the pathogenesis of DFSP may not involve MSI.

A Japanese case of melanoma of unknown origin with a rare BRAFV600R mutation was successfully treated with BRAF/MEK inhibitors.

Combination therapy with BRAF and MEK inhibitors (BRAF/MEKi) has shown significantly prolonged progression-free survival (PFS) and overall survival (OS) for BRAF mutated melanoma. Over 90% of the activating mutations are BRAFV600E or BRAFV600K changes. There are no reports of BRAFV600R in Japanese patients with melanoma. The third most common BRAF mutation is BRAFV600R. In this case, we detected the BRAFV600R mutation with FoundationOne CDx in a Japanese patient with melanoma.. The patient was treated with BRAF/MEKi and maintained stable disease status for 1 year.

Intertumor and intratumor heterogeneity of PIK3CA mutations in extramammary Paget's disease.

Although the prognosis of patients with extramammary Paget's disease (EMPD) treated with radical resection is good, the prognosis of EMPD with distant metastasis is very poor. PIK3CA mutations predict a good response to PIK3CA inhibitors. The aim of this study was to investigate the occurrence rate of PIK3CA mutations (including multiple mutations [MM]) related to the intertumor and intratumor heterogeneity in EMPD and to evaluate the correlation between these mutations and clinical parameters of EMPD. We performed droplet digital polymerase chain reaction to detect PIK3CA mutations (E542K, E545K, H1047R, and MM) in 68 patients with EMPD. In addition, we investigated the presence of PIK3CA mutations at multiple sites in 16 patients with PIK3CA mutations to assess the intratumor heterogeneity of PIK3CA mutations in EMPD. The frequency of one or more PIK3CA mutations in patients with EMPD was 30.8% (21/68). The frequency of E542K, E545K, H1047R, and MM were 10.2% (7/68), 13.2% (9/68), 11.7% (8/68), and 4.4% (3/68), respectively. No significant correlation was found between PIK3CA mutation patterns and clinical parameters. Of the 21 patients with PIK3CA mutations, 16 with tissue samples that could be analyzed at multiple sites were examined. The proportion of patients with the same PIK3CA mutations at all sites was 12.5% (2/16). The proportion of patients with the same PIK3CA mutations at least two or more sites, but not at all sites, was 31.2% (5/16). The proportion of patients with no PIK3CA mutations at other sites was 37.5% (6/16). The proportion of patients with other PIK3CA mutations at other sites was 18.7% (3/16). There is intertumor and intratumor heterogeneity of PIK3CA mutations. PIK3CA mutations in EMPD may be progressor mutations in EMPD.