Pityriasis Lichenoides et Varioliformis Acuta Developing during Pembrolizumab Treatment for Bladder Cancer.

Introduction: Anti-PD-1 immunotherapies enhance T-cell responses against tumor cells by blocking the interaction between PD-1 and its ligand, PD-L1. While these therapies offer significant benefits in treating various malignancies, they can also lead to several immune-related adverse events (irAEs), most notably manifesting in the skin. Lichenoid reactions, eczema, and vitiligo are the three most prevalent forms of cutaneous irAE. Case Presentation: Here, we report a rare case of a pityriasis lichenoides et varioliformis acuta (PLEVA) that developed during pembrolizumab treatment for invasive bladder cancer. A 53-year-old man, receiving pembrolizumab for invasive bladder cancer, developed erythematous papules on his legs after his 11th infusion. The skin lesions gradually spread to his entire trunk and extremities. A punch biopsy revealed several apoptotic keratinocytes and spongiosis, along with perivascular and lichenoid lymphocytic infiltration with vacuolar alteration. Immunohistochemistry showed infiltration of CD4+ and CD8+ T cells in both the epidermis and dermis. Granzyme B-positive inflammatory cells were also slightly present. From these results, he was diagnosed with PLEVA, which might be classified as a lichenoid eruption, especially based on the histological findings. Conclusion: We hypothesize that the anti-PD-1 antibody might lead to epidermal necrosis by amplifying the expression of cytolytic molecules such as granzyme B in CD8+ T cells.

Anti-inflammatory and antifibrotic effects of CBP/ß-catenin inhibitor for hepatocytes: small molecular inhibitor, OP-724 possibly improves liver function.

Wnt/ß-catenin signals are associated with several functions, including organ fibrosis. A synthetic small molecule, OP-724 (prodrug of C-82), an inhibitor of cyclic AMP response element-binding protein (CREB)-binding protein (CBP)/ß-catenin, has demonstrated antifibrotic activity in mouse models of hepatic fibrosis. OP-724 is mediated by profibrotic and antifibrotic cells, such as hepatic stellate cells, macrophages, and neutrophils. In this study, the direct effects of C-82 on hepatocytes in hepatic inflammation were investigated. Immortalized human hepatocytes were pretreated with inflammatory cytokines. Moreover, the alteration of mRNA and protein expressions of cytokines and chemokines associated with hepatic inflammation and fibrosis, and of mitochondria-related molecules after C-82 treatment were analyzed in this study. The mRNA expression of several proinflammatory and profibrotic chemokines was upregulated by the stimulation of these inflammatory cytokines. In addition, this increase was prevented by C-82. In particular, the protein secretion of CCL2, CCL5, CXCL1, CXCL9, and CXCL10 was noticeably upregulated by TNFα and prevented by additional C-82. Moreover, C-82 increased the VEGF-A and FGF-2 proteins, categorized as anti-inflammatory and antifibrotic molecules, respectively. It also increased the expression of mitochondrial components and mitochondrial membrane potential. In conclusion, C-82 inhibits hepatocyte-mediated proinflammation and fibrogenesis. It also directly activates the mitochondrial function, thus improving liver dysfunction.

IsoChichibabin desmosine-13C3,15N1 synthesis and quantitative LC-MS/MS analysis of desmosine and isodesmosine in human skin.

Desmosine and isodesmosine are crosslinking amino acids of elastin, which is an essential component of the dermal extracellular matrix protein. Quantitative analysis of crosslinker desmosines in human skin dermis has not been fully achieved due to the insoluble nature of elastin protein. In the present study, chemical synthesis of isotopically labeled desmosine, desmosine-13C3,15N1, was carried out via isoChichibabin pyridinium synthesis starting from corresponding isotopically labeled amino acids. Isotope-dilution LC-MS/MS analysis of desmosine and isodesmosine utilizing synthetic desmosine-13C3,15N1 enabled the quantitative analysis of desmosines in human skin for the first time. Thus, ca. 1.43 µg of desmosines was detected from analysis of 1 mg of dry human skin.

Epidermal Nevus Syndrome Associated with Dwarfism and Atopic Dermatitis.

Epidermal nevus syndrome (ENS) is a congenital disorder characterized by widespread linear epidermal lesions consisting of epidermal nevus and extracutaneous involvements, especially of the central nervous system and skeletal system. Garcia-Hafner-Happle syndrome, also known as fibroblast growth factor receptor 3 (FGFR3)-ENS, is characterized by a systematized keratinocytic EN of soft and velvety type with neurological abnormalities such as seizures, intellectual impairment, and cortical atrophy. We present a case of a 9-year-old Japanese boy afflicted with Garcia-Hafner-Happle syndrome associated with dwarfism and atopic dermatitis. We show the results of physical examination, DNA analysis, and imaging studies and discuss the mutation underlying the child's disorder.

Risk factors for arthropathy in patients with ulcerative colitis after total colectomy.

OBJECTIVE: Patients with ulcerative colitis (UC) often develop arthropathy. The purpose of this study was to determine the frequency of and risk factors for arthropathy in patients with UC who underwent total colectomy which is the final radical treatment lead to remission. METHODS: Patients who underwent total colectomy from January 2007 to April 2016 were analyzed for the development of arthropathy. The type of arthropathy and risk factors for developing arthropathy were analyzed by clinical and endoscopic severity classification, extraintestinal manifestations (EIMs) and medical treatment. RESULTS: Total of 219 patients who underwent total colectomy with sufficient medical records were analyzed. Forty-eight cases (21.9%) had EIMs, and 40 cases (18.2%) developed arthropathy (57.0% polyarthropathy; 42.5% peripheral arthropathy). Multivariate analysis showed that severity of Matts classification grade 3 or 4 versus grade 1 or 2 (hazard ratio [HR] 2.31, 95% confidence interval [CI] 1.22-4.36, p < .05) and EIMs other than arthropathy (HR 3.29, 95% CI 1.43-7.58, p < .05) were risk factors for the development of arthropathy. CONCLUSION: This study showed that approximately one fifth of patients with UC who underwent total colectomy developed arthropathy. The risk factors for the development of arthropathy were preoperative endoscopic disease activity and EIMs.

Three-dimensional structure analysis of melanocytes and keratinocytes in senile lentigo.

Senile lentigo or age spots are hyperpigmented macules of skin that commonly develop following long-term exposure to ultraviolet radiation. This condition is caused by accumulation of large numbers of melanosomes (melanin granules) produced by melanocytes within neighboring keratinocytes. However, there is still no consensus regarding the melanosome transfer mechanism in senile lentigo. To date, most pathohistological studies of skin have been two-dimensional and do not provide detailed data on the complex interactions of the melanocyte-keratinocyte network involved in melanosome transfer. We performed a three-dimensional reconstruction of the epidermal microstructure in senile lentigo using three different microscopic modalities to visualize the topological melanocyte-keratinocyte relationship and melanosome distribution. Confocal laser microscopy images showed that melanocyte dendritic processes are more frequently branched and elongated in senile lentigo skin than in normal skin. Serial transmission electron micrographs showed that dendritic processes extend into intercellular spaces between keratinocytes. Focused ion beam-scanning electron micrographs showed that dendritic processes in senile lentigo encircle adjacent keratinocytes and accumulate large numbers of melanosomes. Moreover, melanosomes transferred to keratinocytes are present not only in the supranuclear area but throughout the perinuclear area except on the basal side. The use of these different microscopic methods helped to elucidate the three-dimensional morphology and topology of melanocytes and keratinocytes in senile lentigo. We show that the localization of melanosomes in dendritic processes to the region encircling recipient keratinocytes contributes to efficient melanosome transfer in senile lentigo.

A Novel Method for Visualizing Melanosome and Melanin Distribution in Human Skin Tissues.

Melanin incorporated into keratinocytes plays an important role in photoprotection; however, abnormal melanin accumulation causes hyperpigmentary disorders. To understand the mechanism behind the accumulation of excess melanin in the skin, it is essential to clarify the spatial distribution of melanosomes or melanin in the epidermis. Although several markers have been used to detect melanosomes or melanin, no suitable markers to determine the precise localization of melanin in the epidermis have been reported. In this study, we showed that melanocore-interacting Kif1c-tail (M-INK), a recently developed fluorescent probe for visualizing mature melanosomes, binds to purified melanin in vitro, and applied it for detecting melanin in human skin tissues. Frozen skin sections from different phototypes were co-stained for the hemagglutinin (HA)-tagged M-INK probe and markers of melanocytes or keratinocytes, and a wide distribution of melanin was observed in the epidermis. Analysis of the different skin phototypes indicated that the fluorescent signals of HA-M-INK correlated well with skin color. The reconstruction of three-dimensional images of epidermal sheets enabled us to observe the spatial distribution of melanin in the epidermis. Thus, the HA-M-INK probe is an ideal tool to individually visualize melanin (or melanosome) distribution in melanocytes and in keratinocytes in skin tissues.

Anti-tumor Activity of the Small Molecule Inhibitor PRI-724 Against ß-Catenin-activated Hepatocellular Carcinoma.

BACKGROUND/AIM: CBP is a transcriptional coactivator in the Wnt/ß-catenin pathway that is related to cell kinetics and differentiation. This study aimed to characterize ß-catenin-activated hepatocellular carcinoma (HCC) and evaluate the direct effects of PRI-724 (a selective inhibitor of Wnt/ß-catenin/CBP signaling) on HCC. MATERIALS AND METHODS: Immunohistochemistry for ß-catenin was performed in 199 HCC resected samples. Moreover, using cultured HCC cell lines, cell kinetics and its related proteins were analyzed after treatment of cells with C-82 (active form of PRI-724). RESULTS: Nuclear ß-catenin expression was found in 18% of HCC cases and the tumor sizes in these positive samples were larger. In HCC cell lines with a constitutively activated ß-catenin, C-82 inhibited cell proliferation. C-82 led to an increase in the percentage of cells in the G0/G1 phase of the cell cycle. The percentage of cells in the sub-G1 phase also increased. Moreover, C-82 treatment significantly decreased the expression of cell proliferating markers and increased the expression of apoptosis-related proteins. CONCLUSION: PRI-724(C-82) may be a novel drug for ß-catenin-activated HCC therapy.

Intensive granulocyte and monocyte adsorption apheresis for generalized pustular psoriasis.

Granulocyte and monocyte adsorption apheresis (GMA) is usually performed weekly (consisting of five sessions) for refractory skin diseases, such as generalized pustular psoriasis (GPP). The time to remission of inflammatory bowel diseases has been reported to be significantly shorter in intensive GMA (twice a week) than in regular GMA (once a week). Despite several reports of GPP cases treated with intensive GMA, the efficacy of intensive GMA has not been verified in GPP. Herein, we present two GPP patients with a mutation in the IL36RN gene, who initially received regular GMA, and intensive GMA upon recurrence. There were no adverse effects during regular and intensive GMA for both patients. Because concomitant medication was only prednisolone (20 mg/day) during regular and intensive GMA, intensive GMA showed superiority to regular GMA in patient 1. Although concomitant medications were different between regular and intensive GMA in patient 2, these drugs had been used before the start of each GMA therapy. We cannot neglect the effects of concomitant drugs, but we observed a shorter time to remission in intensive GMA than that in regular GMA in both patients. More case studies will be necessary for evaluating the clinical efficacy of intensive GMA.

Activation of STING signaling accelerates skin wound healing.

BACKGROUND: The process of repair after skin injury is precisely regulated by a variety of mediators such as cytokines and chemokines. Recent reports demonstrated that cytoplasmic DNA-sensor cyclic GMP-AMP synthase (cGAS) activates the stimulator of interferon genes (STING) via production of cyclic GMP-AMP (cGAMP) and subsequently induces inflammatory cytokines, including type I interferon (IFN). OBJECTIVE: We examined whether activation of the STING pathway by cGAMP affects the process of skin wound repair. METHODS: The skin wound repair model was established using wild-type (WT) mice. Two full-thickness skin biopsies were taken from the right and left subscapular regions. One site was treated with ointment containing cGAMP, and the other was treated with a control ointment. Changes in wound size over time were calculated using photography. RESULTS: Treatment with cGAMP significantly accelerated skin wound healing up to day 6. Biochemical analyses showed that topical treatment with cGAMP on wound sites promoted STING signaling pathway and enhanced the expression of IFN-ß, CXCL10 and CCL2 in the wound sites treated with cGAMP markedly compared with the control. The scratch assay also revealed that cGAMP treatment accelerated wound closure in mouse embryonic fibroblasts. The acceleration of skin wound repair by cGAMP in WT mouse was impaired by administration of anti-IFNR antibody and anti-CXCR3 antibody respectively. CONCLUSION: These results revealed that topical treatment with cGAMP accelerates skin wound healing by inducing type I IFN and CXCL10/CXCR3. Topical administration of cGAMP might contribute to new effective treatments for accelerating skin wound healing.

Activation of ERK/IER3/PP2A-B56γ-positive feedback loop in lung adenocarcinoma by allelic deletion of B56γ gene.

In order to investigate the involvement of the IER3/PP2A-B56γ/ERK-positive feedback loop, which leads to sustained phosphorylation/activation of ERK in carcinogenesis, we immunohistochemically examined the expression of IER3 and phosphorylated ERK in lung tumor tissues. IER3 was overexpressed in all cases of adenocarcinomas examined, but was not overexpressed in squamous cell carcinomas. Phosphorylated ERK (pERK) was also overexpressed in almost all adenocarcinomas. EGFR and RAS, whose gene product is located upstream of ERK, were sequenced. Activating mutation of EGFR, which is a possible cause of overexpression of IER3 and pERK, was found only in 5 adenocarcinomas (42%). No mutation of RAS was found. We further examined the sequences of all exons of B56γ gene (PPP2R5C) and IER3, but no mutation was found. Using a single nucleotide insertion in intron 1 of PPP2R5C, which was found in the process of sequencing, allelic deletion of PPP2R5C was examined. Eight cases were informative (67%), and the deletion was found in 4 of them (50%). Three cases having deletion of PPP2R5C did not have EGFR mutation. Finally, PPP2R5C deletion or EGFR mutation that could be responsible for IER3/pERK overexpression was found in at least 8 cases (67% or more). This is the first report of a high incidence of deletion of PPP2R5C in human carcinomas.

In situ UDP-glucose regeneration unravels diverse functions of plant secondary product glycosyltransferases.

The catalytic function of plant secondary product glycosyltransferases (PSPGs) was investigated by coupling the activities of recombinant flavonoid glucosyltransferases having different regiospecificities with sucrose synthase from Arabidopsis thaliana. In the present system, UDP, a product inhibitor of PSPGs, was removed from the reaction mixture and used for regeneration of UDP-glucose by AtSUS1. The in situ UDP-glucose regeneration system not only enhanced the glucosylation efficiency but also unraveled the novel regioselectivity of PSPGs. The effect of the system was shown to be because of the removal of UDP from the reaction system and not because of the additional supply of UDP-glucose.

A single UVB exposure increases the expression of functional KIT in human melanocytes by up-regulating MITF expression through the phosphorylation of p38/CREB.

KIT is an essential receptor that modulates melanocyte function and whose function is disrupted in several pigmentary disorders. However, little is known about the effects of a single UVB exposure on the expression of KIT and two important regulatory transcription factors, MITF and AP-2 alpha, in human melanocytes. We found that a single UVB exposure of human melanocytes induces an early decrease and a subsequent increase in functional KIT expression in concert with up-regulated MITF expression. The increased MITF expression was accompanied by a markedly stimulated and prolonged phosphorylation of p38/CREB. The UVB-stimulated expression of KIT could be completely abolished by a p38 inhibitor, concomitant with a reduced phosphorylation of CREB and a down-regulation of MITF expression. Interestingly, in non-UVB exposed human melanocytes, a MEK inhibitor stimulated the phosphorylation of p38/CREB which was associated with an increased production of MITF and KIT in a pattern similar to that induced by UVB. These findings indicate that UVB stimulates functional KIT expression in human melanocytes via the up-regulation of MITF which is, in turn, due to the activation of p38 and CREB.

Inhibitory effects of whisky congeners on melanogenesis in mouse B16 melanoma cells.

We examined the effect of whisky congeners, substances other than ethanol in whisky, on melanogenesis in mouse B16 melanoma cells. Treatment with whisky congeners significantly blocked melanogenesis. Our results indicate that the inhibitory effects of whisky congeners on melanogenesis is due to direct inhibition of tyrosinase activity and to suppression of tyrosinase protein levels.