Leukomelanoderma Resembling Hyperpigmented Mycosis Fungoides.

Acquired circumscribed hyperpigmented patches and plaques have various differential diagnoses, including post-inflammatory hyperpigmentation and mycosis fungoides (MF). Leukomelanoderma is an uncommon cutaneous condition in which the pathogenesis is not fully elucidated. It has been reported that leukomelanoderma occurs after allergic contact dermatitis from hydroquinone or acute cutaneous graft-versus-host disease (1,2). Hyperpigmented MF is a cutaneous T-cell lymphoma with a frequent CD8+ phenotype (3). Herein, we report a case of leukomelanoderma clinically and histologically resembling hyperpigmented MF. A 55-year-old Japanese woman was referred to our department for evaluation of reticulate pigmentation with pruritic erythema on the face. She had used commercially available depigmenting cosmetic reagents for 20 years and ointment containing 10% hydroquinone for 3 months. Physical examination revealed diffuse hyperpigmentation and demarcated hypopigmented macules on the face and neck (Figure 1, a). Dermoscopy showed depigmented spots and reticulated plus dotted hyperpigmentation; it presented a pseudo-pigment network (Figure 1, b). Histological examination of a tissue specimen biopsied from the lesion showed superficial band-like lymphocytic infiltration in dermis accompanying single cells or small clusters in epidermis (Figure 1, c). Interface changes were observed together with melanophages in the dermis. Melan-A-positive melanocytes were absent. Immunohistochemical analysis demonstrated that the epidermotropic lymphocytes were CD3+CD7-, and they had predominance of CD8+ cells (Figure 1, d). These immunohistochemical results mimicked MF. However, PCR analysis of the T-cell receptor g-gene rearrangement was negative. Closed patch test result with hydroquinone (5% pet.) was graded D2 (+?) and D3 (+). Ten months after discontinuing cosmetic reagents and hydroquinone, the pigmentary changes showed improvement. The pathomechanism of leukomelanoderma is unclear. Although post-inflammatory pigmentation due to allergic or contact dermatitis together with direct depigmenting effects from hydroquinone use has been suggested (1), the immunophenotype of T-cells has not been examined. As observed in our patient, interface changes with melanophages, in addition to frequent CD8+ phenotype of the epidermotropism and dermal infiltrate of lymphocytes, were characteristic for hyperpigmented MF (3). Moreover, minimal CD7 expression was a specific finding for MF (4). T-cell receptor clonality was negative in our patient, but the clonality appears to be detected by PCR in up to 50% of the patients with early MF (3). In contrast, the closed patch test was positive for hydroquinone in our patient, and it is reported that CD8+ T-cells are recruited to the interphase between the epidermis and the dermis of the patients with allergic contact dermatitis (5). CD8+ T-cells might contribute to acute cutaneous graft-versus-host disease-like interface changes and destroy melanocytes in the leukomelanoderma lesion. Allergic contact dermatitis presenting as leukomelanoderma was thus suggested in our patient. However, further reports and studies are required to support this issue. Therefore, we considered it necessary to follow the patient, since MF was not absolutely eliminated.

A newly identified gene Ahed plays essential roles in murine haematopoiesis.

The development of haematopoiesis involves the coordinated action of numerous genes, some of which are implicated in haematological malignancies. However, the biological function of many genes remains elusive and unknown functional genes are likely to remain to be uncovered. Here, we report a previously uncharacterised gene in haematopoiesis, identified by screening mutant embryonic stem cells. The gene, 'attenuated haematopoietic development (Ahed)', encodes a nuclear protein. Conditional knockout (cKO) of Ahed results in anaemia from embryonic day 14.5 onward, leading to prenatal demise. Transplantation experiments demonstrate the incapacity of Ahed-deficient haematopoietic cells to reconstitute haematopoiesis in vivo. Employing a tamoxifen-inducible cKO model, we further reveal that Ahed deletion impairs the intrinsic capacity of haematopoietic cells in adult mice. Ahed deletion affects various pathways, and published databases present cancer patients with somatic mutations in Ahed. Collectively, our findings underscore the fundamental roles of Ahed in lifelong haematopoiesis, implicating its association with malignancies.

Keratinocyte Regnase-1, a Downregulator of Skin Inflammation, Contributes to Protection against Tumor Promotion by Limiting Cyclooxygenase-2 Expression.

We previously showed that the ribonuclease Regnase-1 (Reg1) in keratinocytes plays a role in mitigating skin inflammation by downregulating proinflammatory cytokines. In this study, we explored whether Reg1 also has a protective role against skin carcinogenesis. The chemically induced two-stage carcinogenesis protocol revealed that epidermis-specific Reg1-deficient (Reg1-knockout [Reg1-cKO]) mice developed skin tumors with shorter latency and more multiplicity than control mice. In addition, repeated UVB irradiation readily provoked solar keratosis-like lesions in Reg1-cKO mice. Increased levels of cyclooxygenase 2, whose mRNA (Ptgs2) is reportedly a target of Reg1, have been known to be associated with the development of squamous cell carcinomas. Indeed, Ptgs2 mRNA levels were upregulated in the skin of Reg1-cKO mice after treatment with the tumor promoter 12-O-tetradecanoylphorbol-13-acetate. The level of prostaglandin E2 was higher in 12-O-tetradecanoylphorbol-13-acetate‒treated Reg1-cKO mouse skin than in control mice skin. Moreover, in vivo inhibition of cyclooxygenase 2 attenuated the 12-O-tetradecanoylphorbol-13-acetate‒induced epidermal thickening in Reg1-cKO mice. Finally, REG1 knockdown in human squamous cell carcinomas lines enhanced PTGS2 mRNA levels after 12-O-tetradecanoylphorbol-13-acetate treatment. In conclusion, epidermal Reg1 plays a regulatory role not only in skin inflammation but also in tumor promotion through the downregulation of cyclooxygenase 2. Therefore, forced expression of Reg1 under inflammatory conditions may be relevant to preventing skin cancer.

English version of Japanese guidance for use of biologics for psoriasis (the 2022 version).

This is the English version of Japanese guidance for use of biologics for psoriasis (the 2022 version). As the first biologics for psoriasis in Japan, infliximab and adalimumab, anti-tumor necrosis factor-α antibodies, became available in the field of dermatology in 2010, followed by ustekinumab, an anti-interleukin (IL)-12/IL-23p40 antibody, which was launched in Japan in 2011. Moreover, after 2015, three IL-17 inhibitors, the IL-17A antibody preparations secukinumab and ixekizumab, and an anti-IL-17 receptor antibody preparation brodalumab were marketed. Furthermore, after 2018, the anti-IL23p19 antibody preparations guselkumab and risankizumab, the TNF inhibitor certolizumab pegol, the IL-23 inhibitor tildrakizumab, and the anti-IL-17A/F antibody bimekizumab were marketed. It is important for physicians to select appropriate biologic therapy for each psoriatic patient after due consideration of disease factors, treatment factors, and patient background factors, sharing such information with patients. The followings can be listed as points to be considered for the selection of biologics: drug effects (e.g., strength of effectiveness, time to onset of effectiveness, effectiveness against arthritis, primary failure, secondary failure), safety (e.g., infections, administration-related reactions, and relationships with other comorbidities), convenience for patients (e.g., hospital visit intervals, self-injection, maintenance therapy at clinics, feasibility of drug discontinuation/re-administration), and payment (medical costs) borne by patients. This guidance has been prepared with the aim of allowing dermatologists experienced in the treatment of psoriasis to use biologics appropriately according to the circumstances of individual patients after consideration of the above-mentioned factors.

Loss of epidermal Langerhans cells in psoriasiform lesions of de novo induced or worsened pre-existing psoriasis following uses of immune checkpoint inhibitors.

Immune checkpoint inhibitors (ICI), including monoclonal antibodies to programmed death 1, programmed death ligand 1, and cytotoxic T lymphocyte-associated antigen 4, have provided great therapeutic benefits for cancer patients at advanced stages. However, the introduction of ICI frequently results in the development of immune-related adverse events (irAE) through activation of autoreactive T cells. Here, we present three cases of cancer patients with cutaneous irAE, including development of de novo psoriasis and exacerbation of pre-existing psoriasis. Interestingly, these patients shared an altered histological feature characterized by loss of epidermal CD1a+ cells, namely Langerhans cells (LC), in the psoriasiform lesions in contrast to "conventional psoriasis" exhibiting unchanged or activated LC. A possible underlying mechanism was that ICI-mediated hyperactivation of effector T cells contributed to aggravation or establishment of psoriasis phenotype, which might be associated with direct cytotoxicity or expulsion of LC from the epidermis.

Knockout of Zeb2 ameliorates progression of renal tubulointerstitial fibrosis in a mouse model of renal ischemia-reperfusion injury.

BACKGROUND: Zeb2, a zinc finger E-box-binding homeobox transcription factor, regulates transforming growth factor (TGF)-ß signaling pathway. However, its role in the pathogenesis of acute kidney injury (AKI) and AKI-to-chronic kidney disease (CKD) transition is unclear. METHODS: We evaluated Zeb2 function in a bilateral renal ischemia-reperfusion injury (IRI)-induced AKI model using proximal tubule-specific Zeb2 conditional knockout (Zeb2-cKO) and wild-type (WT) mice, and in renal biopsy samples. RESULTS: In Zeb2-cKO mice, the levels of plasma creatinine and blood urea nitrogen post-IRI were significantly lower than that in WT mice. Immunohistological analysis revealed mild tubular injury, reduced neutrophil infiltration, fewer fibrotic changes and reduced expression of fibrotic proteins [collagen type IV, α-smooth muscle actin (α-SMA), fibronectin and connective tissue growth factor (CTGF)], at 3-14 days post-IRI. Zeb2 expression was upregulated in proximal tubular cells post-IRI in WT mice. Zeb2 siRNA transfection reduced TGF-ß-stimulated mRNA and protein expression of collagen type IV, α-SMA, fibronectin and CTGF in cultured renal tubular cells. Patients with AKI-to-CKD transition exhibited high Zeb2 expression in renal tubules, as revealed by renal biopsy. Hypoxia and CoCl2-treatment upregulated Zeb2 promoter activity and mRNA and protein expression in cultured renal tubular epithelial cells, suggesting a regulatory role for hypoxia. CONCLUSIONS: Zeb2 was upregulated in renal tissues in both mice and humans with AKI. Zeb2 regulates fibrotic pathways in the pathogenesis of AKI and AKI-to-CKD transition. Therefore, inhibition of Zeb2 could be a potential therapeutic strategy for AKI.

Efficacy and Safety of Certolizumab Pegol in Japanese Patients with Moderate to Severe Plaque Psoriasis: 52-Week Results.

INTRODUCTION: Certolizumab pegol (CZP), an Fc-free, PEGylated anti-tumour necrosis factor biologic, dosed at 400 mg every 2 weeks (Q2W) and 200 mg Q2W over 16 weeks, resulted in improvements in Japanese patients with moderate to severe plaque psoriasis (PSO); no new safety signals were identified. We present 52-week efficacy and safety results. METHODS: Patients ≥ 20 years with PSO ≥ 6 months [Psoriasis Area and Severity Index (PASI) ≥ 12, body surface area ≥ 10%, Physician's Global Assessment (PGA) ≥ 3] were randomised 1:2:2 to placebo Q2W, CZP 400 mg Q2W and CZP 200 mg Q2W (400 mg weeks 0/2/4) for 16 weeks. Week 16 PASI 50 responders continued through week 52; CZP 200 mg Q2W-randomised patients were re-randomised 1:1 to CZP 200 mg Q2W or CZP 400 mg Q4W; patients initially randomised to other treatment groups continued in the same group. Outcomes included PASI 75/90/100, PGA 0/1, Dermatology Life Quality Index (DLQI) 0/1, Itch Numeric Rating Scale (INRS) 0, modified Nail Psoriasis Severity Index (mNAPSI), durability of response for week 16 PASI 75/90 responders, and safety. RESULTS: Of 26/53/48 patients randomised to placebo, CZP 400 mg Q2W and CZP 200 mg Q2W, 2/47/39 completed week 52, respectively. PASI 75/90 responses were generally maintained from weeks 16 to 52 for all CZP doses. Most week 16 PASI 75/90 achievers maintained their response through week 52. PASI 75/90/100 responses at week 52 in the CZP 400 mg Q2W and CZP 200 mg Q2W groups were 83.0/81.1/41.5% and 72.9/60.4/18.8%, respectively; DLQI/INRS remission rates were 64.2/50.9% in CZP 400 mg Q2W and 58.3/27.1% in CZP 200 mg Q2W-treated patients. Reductions in mNAPSI observed for CZP-treated groups were maintained through week 52. No new safety signals were identified. CONCLUSION: CZP treatment resulted in improvements in signs and symptoms of PSO, which were maintained through week 52. The 400 mg Q2W dose could provide additional clinical benefit. TRIAL REGISTRATION: NCT03051217.

Long-term efficacy and safety of tildrakizumab in Japanese patients with moderate to severe plaque psoriasis: Results from a 5-year extension of a phase 3 study (reSURFACE 1).

The three part, double-blind, randomized, controlled reSURFACE 1 trial and extension study (NCT01722331) evaluated efficacy and safety of tildrakizumab in adults with moderate to severe plaque psoriasis. Patients with ≥50% improvement from baseline in Psoriasis Area and Severity Index (PASI 50) following treatment with tildrakizumab 100 mg (TIL100) or 200 mg (TIL200) could enter the optional long-term extension study and continue treatment at the same dose for an additional 192 weeks. This subgroup analysis assessed the long-term efficacy and safety of tildrakizumab treatment for Japanese patients enrolled in reSURFACE 1 for up to 5 years of treatment. The primary efficacy outcomes were the proportions of patients who maintained PASI 75 and Physician Global Assessment (PGA) clear or minimal with ≥2-grade reduction from baseline (PGA 0/1) from base study week 64 to extension week 192. Secondary outcomes were the proportion of patients who maintained PASI 90/100 from base study week 64 to extension week 192. Adverse events (AEs) were monitored throughout the study and for up to 20 weeks after the last study visit. Of the 120 Japanese patients who entered the reSURFACE 1 extension study, 43 (79.6%) patients receiving tildrakizumab 100 mg and 58 (87.9%) patients receiving tildrakizumab 200 mg completed the extension study. Of all Japanese patients with PASI 75/90/100 and PGA 0/1 at week 64, 85%/88% receiving TIL100/TIL200 maintained PASI 75, 70%/96% maintained PASI 90, 63%/67% maintained PASI 100, and 68%/72% maintained PGA 0/1 at extension week 192. AEs led to discontinuation in 1.7 patients per 100 patient-years (P100PY) receiving tildrakizumab 100 mg and 0.8 P100PY receiving tildrakizumab 200 mg. Incidences of severe infections, malignancies, confirmed major adverse cardiac events, and hypersensitivity reactions were low in both treatment groups. Through 5 years of treatment, tildrakizumab maintained efficacy and was well tolerated with low rates of AEs of special interest.

Pralatrexate for refractory mycosis fungoides in two Japanese patients.

Pralatrexate has been approved for the treatment of relapsed/refractory peripheral T cell lymphomas. Studies in the U.S. also support the clinical efficacy of pralatrexate to treat advanced-stage cutaneous T-cell lymphomas, but outcomes in Japanese patients have not yet been reported. We herein describe two Japanese patients with heavily-pretreated relapsed/refractory mycosis fungoides that were successfully controlled by pralatrexate.

Human Polyomavirus 6 Detected in Cases of Eosinophilic Pustular Folliculitis.

BACKGROUND: Human polyomaviruses (HPyVs) have been associated with several cutaneous inflammatory conditions. More investigation is needed to identify further presentations of cutaneous pathology associated with HPyVs. Our aim was to investigate the possible association of skin-tropic HPyVs with folliculitis, particularly eosinophilic pustular folliculitis (EPF). METHODS: This study included 55 Japanese patients, comprising 13 patients with EPF and 42 patients with suppurative folliculitis. HPyV DNAs were detected by quantitative polymerase chain reaction. Expression of viral antigen and geographically related viral genotypes were also assessed. RESULTS: Human polyomavirus 6 (HPyV6) DNA was found in 9 of 13 (69%) patients with EPF, a rate significantly higher than that found in suppurative folliculitis (1/42; 2%). Of the 7 HPyV6 DNA-positive EPF specimens analyzed, 4 were positive for HPyV6 small tumor antigen. All the HPyV6 strains detected in this study were of the Asian/Japanese genotype. CONCLUSIONS: The predominant detection of HPyV6 DNA and the expression of viral antigen suggest a possible association between HPyV6 infection and EPF in a subset of patients. Worldwide studies are warranted to determine whether Asian/Japanese genotype HPyV6 is associated preferentially with the incidence and pathogenesis of this eosinophil-related skin disease that has an ethnic predilection for the East Asian population.

Establishment of a mouse model for post-inflammatory hyperpigmentation.

Post-inflammatory hyperpigmentation (PIH) is a common cutaneous condition that can cause a disfigured appearance. However, the pathophysiology of PIH remains poorly understood, at least in part, because an appropriate animal model for research has not been established. In order to analyze the pathomechanism of PIH, we successfully induced PIH in a hairless version of transgenic mice (hk14-SCF Tg/HRM) that have a human-type epidermis containing melanin by repeated hapten application of 2,4-dinitrofluorobenzene. Histopathologic observation showed epidermal hyperplasia, predominant infiltrations of inflammatory cells, and melanin-containing cells in the dermis just after elicitation of the atopic dermatitis-like condition. At week 2, the findings were similar to the characteristics of PIH, that is, an increase of melanin without spongiosis or liquid degeneration in the epidermis and an increase in dermal melanophages. Dynamic analysis of melanin showed that the melanin in the dermis remained for a longer duration than in the epidermis. Furthermore, immunohistochemical staining revealed that the majority of cells containing melanin were positive for the anti-CD68 antibody, but negative for the anti-F4/80 antibody. These data suggest that novel treatments of PIH should be targeted against macrophages and should eventually lead to the development of new treatment modalities.

Exploration of biomarkers to predict clinical improvement of atopic dermatitis in patients treated with dupilumab: A study protocol.

BACKGROUND: Atopic dermatitis (AD) is a common eczematous skin disorder that profoundly reduces the quality of life due to intractable pruritus. Excellent therapeutic success of the anti-interleukin 4 receptor-α antibody dupilumab in clinical trials and a real-world clinical context indicates the crucial roles of interleukin (IL)-4 and IL-13 in the pathogenesis of AD. Along with the clinical improvement in skin scores and pruritus, dupilumab significantly and progressively reduces and normalizes the upregulated expression of T helper type 2 signatures such as Chemokine (C-C motif) ligand (CCL)17, CCL18, CCL22, and CCL26 in the lesional skin of AD. However, no blood/serum biomarkers are known to predict good or poor outcome in patients with AD treated with dupilumab. METHODS: Patients are at least 18 years of age and have moderate-to-severe AD with Eczema Area and Severity Index (EASI) ≥16, Investigator's Global Assessment ≥3, and body surface area ≥10%. We are going to enroll more than 130 subjects from 18 medical facilities. Clinical objective findings will be evaluated by EASI. Subjective symptoms will be assessed by Patient-Oriented Eczema Measure, Numerical Rating Scale for Pruritus (Pruritus-NRS), Skin Comfort-NRS, and Treatment Satisfaction-NRS. We will measure 18 blood/serum biomarkers including % eosinophils in blood cell count, lactate dehydrogenase, total IgE, soluble interleukin 2 receptor, CCL17, CCL18, CCL22, CCL26, CCL27, IL-13, IL-22, IL-24, IL-25, IL-31, IL-33, thymic stromal lymphopoietin, periostin, and squamous cell carcinoma antigen-2. The clinical evaluation and biomarker sampling will be performed at 0, 2, 4, 8, and 16 weeks of dupilumab treatment. We will also perform proteomic analysis (of roughly 300 proteins) of the patients' sera obtained at 0 and 2 weeks of treatment. The primary endpoint is the association between "baseline levels of 18 biomarkers" and "% change from baseline of EASI at 16 weeks of dupilumab treatment." DISCUSSION: This is the first clinical trial to explore the biomarkers, including potential proteomic markers, most strongly associated with improvement in EASI in patients with moderate-to-severe AD treated with dupilumab for 16 weeks (B-PAD study). A limitation is that we will only enroll Japanese patients.

Skin and hair abnormalities of Cantu syndrome: A congenital hypertrichosis due to a genetic alteration mimicking the pharmacological effect of minoxidil.

Cantu syndrome is an autosomal dominant disorder, first described by Cantu in 1982, that is characterized by congenital hypertrichosis, characteristic facial anomalies and cardiomegaly. Recent investigations have revealed that this syndrome is caused by mutations of ABCC9, which encodes a regulatory subunit of SUR2, an adenosine triphosphate-mediated potassium channel opener, expressed not only in smooth muscle but also in hair follicles. However, the abnormalities of skin and hair in patients with Cantu syndrome have not been well explored. We herein report three Japanese patients with Cantu syndrome and describe their specific skin manifestations and alterations in the histopathology of their hair follicles and sebaceous glands. Similar alterations were shared among those three patients and may be related to the function of SUR2, namely the regulation of hair follicle growth, because SUR2 is a known pharmacological target of minoxidil.