AMP kinase-related kinase NUAK2 affects tumor growth, migration, and clinical outcome of human melanoma.

The identification of genes that participate in melanomagenesis should suggest strategies for developing therapeutic modalities. We used a public array comparative genomic hybridization (CGH) database and real-time quantitative PCR (qPCR) analyses to identify the AMP kinase (AMPK)-related kinase NUAK2 as a candidate gene for melanomagenesis, and we analyzed its functions in melanoma cells. Our analyses had identified a locus at 1q32 where genomic gain is strongly associated with tumor thickness, and we used real-time qPCR analyses and regression analyses to identify NUAK2 as a candidate gene at that locus. Associations of relapse-free survival and overall survival of 92 primary melanoma patients with NUAK2 expression measured using immunohistochemistry were investigated using Kaplan-Meier curves, log rank tests, and Cox regression models. Knockdown of NUAK2 induces senescence and reduces S-phase, decreases migration, and down-regulates expression of mammalian target of rapamycin (mTOR). In vivo analysis demonstrated that knockdown of NUAK2 suppresses melanoma tumor growth in mice. Survival analysis showed that the risk of relapse is greater in acral melanoma patients with high levels of NUAK2 expression than in acral melanoma patients with low levels of NUAK2 expression (hazard ratio = 3.88; 95% confidence interval = 1.44-10.50; P = 0.0075). These data demonstrate that NUAK2 expression is significantly associated with the oncogenic features of melanoma cells and with the survival of acral melanoma patients. NUAK2 may provide a drug target to suppress melanoma progression. This study further supports the importance of NUAK2 in cancer development and tumor progression, while AMPK has antioncogenic properties.

Systemic treatment of patients with advanced cutaneous squamous cell carcinoma: response rates and outcomes of the regimes used.

BACKGROUND: Cutaneous squamous cell carcinoma (cSCC) is the second most common type of skin cancer. Few patients with cSCC experience metastases, but the prognosis of advanced cSCC (acSCC) is dismal. Evidence regarding systemic therapy for acSCC is limited. Therefore, we aimed to determine the most effective systemic treatment for acSCC. PATIENTS AND METHODS: This retrospective study involved 16 Japanese institutions. We documented patient and tumour characteristics and disease course of patients with acSCC who received systemic therapy between 1st January 2006 and 31st December 2015. We compared the overall survival (OS) and progression-free survival (PFS) for (1) platinum versus non-platinum groups, (2) radiation plus chemotherapy first-line therapy (RCT) versus non-RCT groups and (3) platinum-based RCT versus non-platinum-based RCT groups. RESULTS: Although the use of platinum-based systemic therapy was not associated with statistically significant improvements in PFS and OS, there were significant differences between the RCT and non-RCT groups (PFS: p < 0.001, OS: p = 0.003). In the subgroup analysis, RCT significantly prolonged PFS and OS in the nodal SCC (nSCC) group. For the RCT and non-RCT groups, the median OS was 110 and 14 months, respectively, and the 5-year OS rate was 54% and 21%, respectively. CONCLUSION: RCT could improve OS in patients with nSCC. However, further multicenter prospective studies are needed to establish evidence for superiority of RCT.

Wound, pressure ulcer and burn guidelines - 6: Guidelines for the management of burns, second edition.

"Wound, pressure ulcer and burn guidelines - 6: Guidelines for the management of burns, second edition" is revised from the first edition which was published in the Japanese Journal of Dermatology in 2016. The guidelines were drafted by the Wound, Pressure Ulcer and Burn Guidelines Drafting Committee delegated by the Japanese Dermatological Association, and intend to facilitate physicians' clinical decisions in preventing, diagnosing and treating burn injury. All sections are updated by collecting documents published since the publication of the first edition. Especially, the recommendation levels of dressing materials newly covered by the Japanese national health insurance are mentioned. In addition, the clinical questions (CQ) regarding the initial treatment of electrical (CQ15) and chemical burns (CQ16), and also the use of escharotomy (CQ22), are newly created.

Wound, pressure ulcer and burn guidelines - 1: Guidelines for wounds in general, second edition.

The Japanese Dermatological Association prepared the clinical guidelines for the "Wound, pressure ulcer and burn guidelines", second edition, focusing on treatments. Among them, "Guidelines for wounds in general" is intended to provide the knowledge necessary to heal wounds, without focusing on particular disorders. It informs the basic principles of wound treatment, before explanations are provided in individual chapters of the guidelines. We updated all sections by collecting references published since the publication of the first edition. In particular, we included new wound dressings and topical medications. Additionally, we added "Question 6: How should wound-related pain be considered, and what should be done to control it?" as a new section addressing wound pain, which was not included in the first edition.

Wound, pressure ulcer and burn guidelines - 4: Guidelines for the management of connective tissue disease/vasculitis-associated skin ulcers.

The Japanese Dermatological Association prepared guidelines focused on the treatment of skin ulcers associated with connective tissue disease/vasculitis practical in clinical settings of dermatological care. Skin ulcers associated with connective tissue diseases or vasculitis occur on the background of a wide variety of diseases including, typically, systemic sclerosis but also systemic lupus erythematosus (SLE), dermatomyositis, rheumatoid arthritis (RA), various vasculitides and antiphospholipid antibody syndrome (APS). Therefore, in preparing the present guidelines, we considered diagnostic/therapeutic approaches appropriate for each of these disorders to be necessary and developed algorithms and clinical questions for systemic sclerosis, SLE, dermatomyositis, RA, vasculitis and APS.

Oculocutaneous albinism type IV: A boy of Moroccan descent with a novel mutation in SLC45A2.

Oculocutaneous albinism type IV (OCA4 [MIM606574]) caused by mutations of the SLC45A2 gene is an autosomal recessive disorder of pigmentation characterized by reduced biosynthesis of melanin pigment in the skin, hair, and eye. We had the opportunity to examine a Belgian boy of Moroccan descent with clinically severe OCA and screened the mutation in his SLC45A2 gene. Sequencing of exon 1, of which the PCR product showed aberrant patterns in the SSCP gel, revealed that the patient was a homozygote for p.H38R mutation. We demonstrated that the p.H38R-mutant protein was functionally incapable of melanin synthesis using melanocyte cultures (under white cells; uw) established from a mouse model of OCA4. This is the second report of the occurrence of OCA4 in a member of an African ethnic group.

Case of hypereosinophilic syndrome with cutaneous necrotizing vasculitis.

A 25-year-old male presented with pruritic papules over his trunk and extremities. The pruritic eruption had appeared on the arms 5 months before and gradually spread over the trunk. Blood tests showed a white blood cell count of 13 760/microL with 42.2% eosinophils. A skin biopsy from the leg revealed necrotizing vasculitis in the upper dermis with prominent eosinophil infiltration in the dermis and subcutis. Liver dysfunction in accordance with eosinophilia was also seen. The underlying disorder causing the eosinophilia was not detected. We diagnosed this case as hypereosinophilic syndrome. Although systemic corticosteroid therapy using prednisolone was effective, the symptoms recurred during a reduction of prednisolone. The addition of cyclosporine resulted in improvement of his symptoms. Both drugs were successfully tapered without relapsing symptoms. Hypereosinophilic syndrome with cutaneous necrotizing vasculitis is a rare condition, and this case suggests that cyclosporine may be a useful therapeutic adjunct in facilitating steroid tapering.

Characterization of melanosomes and melanin in Japanese patients with Hermansky-Pudlak syndrome types 1, 4, 6, and 9.

Hermansky-Pudlak syndrome (HPS) is an autosomal recessive disorder characterized by oculocutaneous albinism (OCA), a bleeding tendency, and ceroid deposition. Most of the causative genes for HPS encode subunits of the biogenesis of lysosome-related organelles complex (BLOC). In this study, we identified one patient each with HPS4, HPS6, and HPS9 by whole-exome sequencing. Next, we analyzed hair samples from the three patients and representative patients with HPS1 and controls using electron microscopy and chemical methods. All HPS patients had fewer, smaller, and more immature melanosomes than healthy controls. Further, all patients showed reduced total melanin content and increased levels of benzothiazine-type pheomelanin. The results of this study demonstrate the impact of the dysfunctions of BLOCs on the maturation of melanosomes and melanin levels and composition through analysis of their hair samples.

Rhododenol-induced leukoderma in a mouse model mimicking Japanese skin.

BACKGROUND: Rhododendrol, 4-(4-hydroxyphenyl)-2-butanol, Rhododenol(®) (RD), a naturally occurring phenolic compound, was developed as a tyrosinase inhibitor for skin-lightening/whitening cosmetics. In 2013, skin depigmentation was reported in consumers using RD-containing skin-brightening cosmetics; this condition is called RD-induced leukoderma. OBJECTIVE: The etiology of RD-induced leukoderma is still largely unknown. Here, to assess the depigmentation potential of RD, we developed a new mouse model of leukoderma by topically applying RD. METHODS: Hairless hk14-SCF Tg mice with melanocytes distributed in the epidermis were used for this study. RD was applied on the dorsal skin of the mice daily for 28 days. Then, immunohistological, biochemical, and electron microscopic analyses were performed on biopsy samples taken from these mice. RESULTS: The depigmentation in the RD-treated sites appeared on Day 14. Histological examination indicated a loss of epidermal melanocytes at Day 7. On the other hand, the melanocyte number did not decrease in the albino mice having the same background as the hairless hk14-SCF Tg, but without tyrosinase activity. Biochemical analyses showed that the eumelanin content decreased in the RD-treated sites and metabolites of RD-quinone, i.e., non-protein thiol adducts and protein-SH adducts, were produced. Electron microscopic analyses revealed double-membrane-walled structures containing electron-dense material, which might be typical for melanin-containing autophagosomes and a dilated endoplasmic reticulum (ER), which would indicate ER stress. CONCLUSIONS: These data suggested that RD exerted tyrosinase-dependent melanocyte cytotoxicity and that tyrosinase-dependent accumulation of ER stress from activation of the autophagy pathway contributed to melanocyte cytotoxicity.

The wound/burn guidelines - 6: Guidelines for the management of burns.

Burns are a common type of skin injury encountered at all levels of medical facilities from private clinics to core hospitals. Minor burns heal by topical treatment alone, but moderate to severe burns require systemic management, and skin grafting is often necessary also for topical treatment. Inappropriate initial treatment or delay of initial treatment may exert adverse effects on the subsequent treatment and course. Therefore, accurate evaluation of the severity and initiation of appropriate treatment are necessary. The Guidelines for the Management of Burn Injuries were issued in March 2009 from the Japanese Society for Burn Injuries as guidelines concerning burns, but they were focused on the treatment for extensive and severe burns in the acute period. Therefore, we prepared guidelines intended to support the appropriate diagnosis and initial treatment for patients with burns that are commonly encountered including minor as well as moderate and severe cases. Because of this intention of the present guidelines, there is no recommendation of individual surgical procedures.

The wound/burn guidelines - 2: Guidelines for the diagnosis and treatment for pressure ulcers.

The Wound/Burn Guidelines Committee consists of members commissioned by the Board of Directors of the Japanese Dermatological Association (JDA). It held several meetings and evaluations in writing since October 2008, and drafted five guidelines for the diagnosis and treatment including commentaries on wounds in general and the Guidelines for the Diagnosis and Treatment for Pressure Ulcers by taking opinions of the Scientific Committee and Board of Directors of JDA into consideration.

The wound/burn guidelines - 4: Guidelines for the management of skin ulcers associated with connective tissue disease/vasculitis.

The Japanese Dermatological Association prepared guidelines focused on the treatment of skin ulcers associated with connective tissue disease/vasculitis practical in clinical settings of dermatological care. Skin ulcers associated with connective tissue diseases or vasculitis occur on the background of a wide variety of diseases including, typically, systemic sclerosis but also systemic lupus erythematosus (SLE), dermatomyositis, rheumatoid arthritis (RA), various vasculitides and antiphospholipid antibody syndrome (APS). Therefore, in preparing the present guidelines, we considered diagnostic/therapeutic approaches appropriate for each of these disorders to be necessary and developed algorithms and clinical questions for systemic sclerosis, SLE, dermatomyositis, RA, vasculitis and APS.

The wound/burn guidelines - 1: Wounds in general.

The Japanese Dermatological Association determined to prepare the Wound/Burn Guidelines focusing on treatments, catering to needs for the clinical practice of dermatology. Among these guidelines, "Wounds in General" was intended to explain knowledge necessary "to heal wounds" without specifying particular disorders.

The wound/burn guidelines - 3: Guidelines for the diagnosis and treatment for diabetic ulcer/gangrene.

We aimed to prepare guidelines for the management of diabetic ulcer/gangrene with emphasis on the diagnosis and treatment of skin symptoms. They serve as a tool to improve the quality of the diagnosis and treatment in each patient and, further, to improve the level of the care for diabetic ulcer in Japan by systematically presenting evidence-based recommendations for clinical judgments by incorporating various viewpoints.

The wound/burn guidelines - 5: Guidelines for the management of lower leg ulcers/varicose veins.

Varicose veins are treated at multiple clinical departments, but as patients often visit the dermatology clinic first due to leg ulcers, the present Guidelines for the Management of Lower Leg Ulcers/Varicose Veins were prepared in consideration of the importance of the dermatologist's role. Also, the disease concept of chronic venous insufficiency or chronic venous disorders and the CEAP classification of these disorders are presented. The objective of the present guidelines is to properly guide the diagnosis and treatment of lower leg ulcers/varicose veins by systematically presenting evidence-based recommendations that support clinical decisions.

Topical vitamin D3 is effective in treating senile warts possibly by inducing apoptosis.

Vitamin D3 ointments containing active forms of vitamin D3 are widely used to treat inflammatory keratotic dermatoses such as psoriasis. Senile wart or seborrheic keratosis is a benign tumor which occurs mainly in the elderly. It has traditionally been treated with surgical procedures, freezing with liquid nitrogen, or laser therapy. We treated senile warts with topical vitamin D3 ointments (tacalcitol, calcipotriol or maxacalcitol). Out of 116 cases treated for 3 to 12 months, 35 (30.2%) showed complete disappearance or more than an 80% decrease in the volume of the tumor, 54 cases (46.6%) showed a decrease in the volume between 40 and 80%, and no remarkable changes or decreases of less than 40% were seen in 27 cases (23.3%). The tumors faded without any inflammatory changes such as erythema or swelling. An organ culture experiment using senile wart as a material with several concentrations of tacalcitol revealed that tacalcitol induced apoptosis in the tissue. On the other hand, only sporadic apoptotic cells were seen in the controls (p<0.001). Vitamin D3 may affect senile warts by inducing apoptosis. Clearance of senile warts, especially on exposed areas without pain, may improve the quality of life (QOL) of the elderly.

ADAM protease inhibitors reduce melanogenesis by regulating PMEL17 processing in human melanocytes.

BACKGROUND: ADAMs (a disintegrin and metalloprotease) are a family of proteases involved in ectodomain shedding that play a role in various biological processes such as cell adhesion and migration. ADAM10 and ADAM17 are suggested to be involved in pigmentary disorders. OBJECTIVE: We examined the effect of ADAM protease inhibitors on the modulation of melanogenesis in normal human epidermal melanocytes (NHEM). METHODS: NHEMs and B16F10 treated with ADAM protease inhibitors were analyzed. AlamarBlue cell proliferation assay, melanin content assay, tyrosinase activity assay, Western blotting analysis, electron microscopic analysis, and RNA interference were employed. RESULTS: In NHEMs, melanin content was reduced by treatment with ADAM protease inhibitors. The inhibitors did not change the protein expression of tyrosinase, TRP-1, and MITF. In B16F10 cells, treatment of the cells with ADAM protease inhibitor diminished the α-MSH-induced increase in melanin content. Electron microscopy showed that the number of fibrillar and mature melanosomes was significantly reduced and that the vacuolar compartments were filled with dense unstructured aggregates after treatment with ADAM protease inhibitors. We therefore focused on the processing of PMEL17, a melanosomal glycoprotein that forms a fibrillar matrix on which melanin gets deposited. Proteolytic processing of PMEL17 is required to form functional fibrils during melanogenesis. Recently, γ-secretase and ß-site amyloid precursor protein-cleaving enzyme 2 (BACE2) were found to cleave PMEL17. We found that ADAM protease inhibitors exerted effects on the processing of C-terminal and N-terminal fragments of PMEL17. Using BACE2 siRNA and γ-secretase inhibitor, we showed that ADAM protease inhibitor affected PMEL17 processing in a γ-secretase and BACE2-independent mechanism. CONCLUSION: Several proteases, including ADAM proteases, can contribute to the formation of fibrils and their assembly into sheets in melanosomes.

NUAK2 Amplification Coupled with PTEN Deficiency Promotes Melanoma Development via CDK Activation.

The AMPK-related kinase NUAK2 has been implicated in melanoma growth and survival outcomes, but its therapeutic utility has yet to be confirmed. In this study, we show how its genetic amplification in PTEN-deficient melanomas may rationalize the use of CDK2 inhibitors as a therapeutic strategy. Analysis of array-CGH data revealed that PTEN deficiency is coupled tightly with genomic amplification encompassing the NUAK2 locus, a finding strengthened by immunohistochemical evidence that phospho-Akt overexpression was correlated with NUAK2 expression in clinical specimens of acral melanoma. Functional studies in melanoma cells showed that inactivation of the PI3K pathway upregulated p21 expression and reduced the number of cells in S phase. NUAK2 silencing and inactivation of the PI3K pathway efficiently controlled CDK2 expression, whereas CDK2 inactivation specifically abrogated the growth of NUAK2-amplified and PTEN-deficient melanoma cells. Immunohistochemical analyses confirmed an association of CDK2 expression with NUAK2 amplification and p-Akt expression in melanomas. Finally, pharmacologic inhibition of CDK2 was sufficient to suppress the growth of NUAK2-amplified and PTEN-deficient melanoma cells in vitro and in vivo. Overall, our results show how CDK2 blockade may offer a promising therapy for genetically defined melanomas, where NUAK2 is amplified and PTEN is deleted.