Role of interleukin-6 and endothelin-1 receptors in enhanced melanocyte dendricity of facial spots and suppression of their ligands by niacinamide and tranexamic acid.

BACKGROUND: Hyperpigmented spots are common issues in all ethnicities with a hallmark characteristic of increased melanocyte dendricity. OBJECTIVES: To determine (1) potential receptors and/or cytokines that are involved in increased melanocyte dendricity in multiple facial spot types; (2) treatment effects of skin-lightening compounds on identified cytokine release from keratinocytes and on dendricity in melanocytes. METHODS: Facial spots (melasma, solar lentigo, acne-induced post-inflammatory hyperpigmentation) and adjacent non-spot skin biopsies were collected from Chinese women (age 20-70). The epidermal supra and basal layers were laser dissected to enrich keratinocyte or melanocyte biology respectively for transcriptome analysis. Melanocyte dendricity was assessed histologically by immunofluorescent staining. Effect of interleukin-6 (IL-6) and endothelin-1 (ET-1) on melanocyte dendricity and melanosome transfer were assessed in human melanocytes or melanocyte-keratinocyte co-culture models. Treatment effects of skin-lightening compounds (niacinamide, tranexamic acid [TxA], sucrose laurate/dilaurate mixture [SDL]) were assessed on IL-6 or ET-1 release from keratinocytes and on dendricity in melanocytes. RESULTS: Transcriptome analysis revealed IL-6 receptor and ET-1 receptor were significantly upregulated compared to the adjacent normal skin, visually confirmed at the protein level through immunostaining. Melanocytes in spot areas are more dendritic than melanocytes in adjacent non-spot skin. The addition of IL-6 and ET-1 to cell culture models increased melanocyte dendricity and melanosome transfer. IL-6 release was significantly suppressed by niacinamide and its combination, while ET-1 release was significantly reduced by both niacinamide and TxA. In contrast, SDL acted directly upon melanocytes to reduce dendricity. CONCLUSION: Interleukin-6 and ET-1 receptors are significantly upregulated in multiple facial spot types. The in vitro testing demonstrated their respective ligands increased melanocyte dendricity. Tested skin-lightening compounds showed reduction in release of IL-6/ET-1 from epidermal keratinocytes and/or inhibition of melanocyte dendricity. This work sheds light on pathophysiological mechanism of facial spots and potential new mechanisms of these skin-lightening compounds which warrant further human clinical validation.

A case of nivolumab-induced acute-onset type 1 diabetes mellitus in melanoma.

Nivolumab, an anti-PD-1 antibody, is now considered an important therapeutic agent in several advanced malignancies. However, immune-related adverse events such as endocrinopathies have been reported with its use. Thyroid disorder and isolated adrenocorticotropic hormone deficiency have frequently been reported as nivolumab-induced immune-related adverse events. Another endocrinopathy is nivolumab-induced type 1 diabetes mellitus (t1dm), described as diabetes mellitus with rapid onset and complete insulin insufficiency, at times leading to fulminant t1dm. We report the case of a 68-year-old woman who developed pancreatic islet-related autoantibody-negative t1dm, possibly induced by nivolumab, under continuous glucocorticoid administration. She was treated with nivolumab for advanced malignant melanoma, concomitant with 10 mg prednisolone daily for thrombophlebitis tapered to 5 mg after 13 courses of nivolumab therapy. At approximately the 27th course of nivolumab therapy, she showed elevated plasma glucose levels despite preserved insulin secretion. A month later, she developed diabetic ketoacidosis. Her insulin secretion decreased and finally was exhausted. She was diagnosed with acute-onset rather than fulminant t1dm because of a rapidly progressive course to diabetic ketoacidosis during just more than 1 week. She is currently receiving insulin replacement. There has been no recurrence of the melanoma. Thus, nivolumab might induce autoimmune diabetes mellitus, with patients having t1dm-sensitive human leucocyte antigen being more susceptible even when receiving glucocorticoids. Physicians should be aware that nivolumab could potentially induce t1dm as a critical immune-related adverse event.

An XPA gene splicing mutation resulting in trace protein expression in an elderly patient with xeroderma pigmentosum group A without neurological abnormalities.

A certain relationship between XPA gene mutations and the severity of symptoms has been observed in patients with xeroderma pigmentosum group A (XP-A). Patients with mutations within the DNA-binding domain usually exhibit severe symptoms, whereas splicing mutations in the same domain sometimes cause very mild symptoms. This inconsistency can be explained by a small amount of functional XPA protein produced from normally spliced transcripts. We herein report the case of an adult Japanese patient with XP-A with unusually mild symptoms. We identified a homozygous c.529G>A mutation in exon 4 of the XPA gene, which resulted in aberrant splicing with a 29-bp deletion in exon 4 causing a frameshift. Intact mRNA was observable, but a Western blot analysis failed to detect any normal XPA protein. We therefore evaluated the DNA repair capacity in normal cells in which the XPA expression was artificially diminished. The repair capacity was still present in cells with trace levels of the XPA protein. The repair capacity of the cells derived from our patient with mild symptoms was poor by comparison, but still significant compared with that of the cells derived from a patient with XP-A with severe symptoms. These results provide strong evidence that a trace level of XPA protein can still exert a relatively strong repair capacity, resulting in only a mild phenotype.

Analysis of sebum lipid composition and the development of acneiform rash before and after administration of egfr inhibitor.

Treatment with an epidermal growth factor receptor inhibitor (egfri) in patients having non-small-cell lung cancer can cause frequent and diverse skin toxicities, an acneiform rash being one of the commonest. Although the exact pathophysiology of this rash and its development mechanisms remain unknown, investigators have noted that egfri-induced skin toxicity might be partly associated with sebaceous gland function. Sebum is composed mainly of the lipids squalene (sq), wax ester (we), triglyceride, free fatty acid, and cholesterol, which are secreted mostly from the sebaceous glands and by keratinocytes. We therefore investigated the lipid composition of sebum before and after administration of egfri and whether sebum composition was associated with the development of acneiform rash. To investigate any associated changes in sebum gland activity, we focused especially on alterations in the amounts of sq and we, which are secreted solely from the sebaceous glands. In contrast to our expectations, we observed no substantial changes in the lipid composition of sebum before and after administration of egfri. Composition varies with the individual; however, the proportion of sq and we derived from the sebaceous glands was significantly lower in regions that did not develop acneiform rash than in regions that did. Our results suggest that development of an acneiform rash after administration of egfri could be related to sebaceous gland activity. Measurement of the lipid composition of sebum before therapy with egfri might predict which patients will be prone to acneiform rash.

Triple-marker PCR assay of sentinel lymph node as a prognostic factor in melanoma.

BACKGROUND: Metastasis of sentinel lymph node (SLN) is generally evaluated on histopathological examination and controversy still exists over the usefulness of PCR assay of SLN. OBJECTIVE: To investigate the prognostic value of triple-marker PCR assay of SLN. METHODS: A total of 165 patients with primary cutaneous melanoma who underwent SLN biopsy were included. Clinical and histopathological data were retrieved from each patient's file and triple-marker PCR assay (tyrosinase, GP-100 and MART-1) was performed on the SLN as well as routine histopathological evaluation. PCR positivity was defined as the expression of all three PCR markers. To evaluate melanoma-specific survival (MSS) and disease-free survival (DFS), we used the Kaplan-Meier method and the log-rank test. Multivariate analyses using the Cox proportional hazards regression model were also performed. RESULTS: Sentinel lymph nodes were identified in all 165 patients: 61 patients (37.0%) were male and 104 (63.0%) were female, with a mean age of 60.2 years. Of the 165 melanomas, 81 (49.1%) were acral lentiginous melanomas. Compared with the patients with PCR positivity (1-2 markers) or PCR negativity, patients with PCR positivity (3 markers) had significantly poor MSS (5-year survival rate, 58.7% vs. 84.4%; P < 0.0001) and DFS (5-year survival rate, 25.0% vs. 83.9%; P < 0.0001), with median follow-up of 42 months for MSS and 38 months for DFS. These survival rates of patients with PCR positivity (3 markers) were lower than those of patients with histopathologically positive SLN. In multivariate analysis, PCR positivity (3 markers) was an independent prognostic factor for both MSS (hazard ratio [HR], 2.81; 95% confidence interval [CI], 1.07-7.33; P = 0.035) and DFS (HR, 2.48; 95% CI, 1.08-5.69; P = 0.032). CONCLUSIONS: The expression of three PCR markers was a significant prognostic factor for both MSS and DFS and might be closely correlated to a dismal prognosis.

Narrow-margin excision is a safe, reliable treatment for well-defined, primary pigmented basal cell carcinoma: an analysis of 288 lesions in Japan.

BACKGROUND: Complete excision is the most promising treatment for basal cell carcinoma (BCC) and a surgical margin of at least 4 mm is recommended. However, little is known about the appropriate surgical margin of pigmented BCC. OBJECTIVE: To investigate the reliability of narrower margin excision of well-defined, pigmented BCC. METHODS: We identified a total of 263 patients with 288 well-defined, primary pigmented BCC at the Department of Dermatology, Kyushu University (Fukuoka, Japan), between January 2006 and December 2013. All lesions were surgically excised with 1-6-mm margins and analysed. For 30 recent lesions out of the 288 lesions, border gaps between dermoscopy and histopathology were assessed. RESULTS: Of the 288 lesions, 218 (75.7%) were excised with a narrow margin (≤ 3 mm) and 60 lesions (24.3%) with a wide margin (≥ 4 mm). Only two lesions (0.7%), which were excised with 2-mm margins, were associated with tumour-positive margins. Narrow-margin excision showed a complete removal rate of 99% (2-mm margins, 95.3%; 3-mm margins, 100%). Dermoscopically determined borders almost exactly corresponded to the histopathological ones; 71.2% of border gaps between dermoscopy and histopathology were within 1 mm and there were no cases in which tumours spread beyond 1 mm of their dermoscopic borders. CONCLUSION: Surgical excision with a 2-3-mm margin is reliable treatment for well-defined, primary pigmented BCC, with a complete removal rate of 99%.

Inhibition of AHR transcription by NF1C is affected by a single-nucleotide polymorphism, and is involved in suppression of human uterine endometrial cancer.

Involvement of the aryl hydrocarbon receptor (AHR) in carcinogenesis has been suggested in many studies. Upregulation of AHR has been reported in some cancer species, and an association between single-nucleotide polymorphisms (SNPs) of AHR and cancer risk or cancer development has also been reported. This evidence suggests the involvement of some specific SNPs in AHR transcriptional regulation in the process of carcinogenesis or cancer development, but there have been no studies to elucidate the mechanism involved. In this study, we identified the transcription factor Nuclear Factor 1-C (NF1C) as a candidate to regulate AHR transcription in a polymorphism-dependent manner. SNP rs10249788 was included in a consensus binding site for NF1C. Our results suggested that NF1C preferred the C allele to the T allele at rs10249788 for binding. Forced expression of NF1C suppressed the activity of the AHR promoter with C at rs10249788 stronger than that with T. Moreover, expression analysis of human uterine endometrial cancer (HEC) specimens showed greater upregulation of AHR and downregulation of NF1C than those of normal endometrium specimens. Sequence analysis showed HEC patients at advanced stages tended to possess T/T alleles more frequently than healthy women. We also demonstrated that NF1C suppressed proliferation, motility and invasion of HEC cells. This function was at least partially mediated by AHR. This study is the first to report that a polymorphism on the AHR regulatory region affected transcriptional regulation of the AHR gene in vitro. Because NF1C is a tumor suppressor, our new insights into AHR deregulation and its polymorphisms could reveal novel mechanisms of genetic susceptibility to cancer.

A Case of Sparganosis mansoni in the Thigh: Serological Validation of Cure Following Surgery.

Cases of Sparganum mansoni, caused by the plerocercoid larva of the tapeworm S. mansoni, occur throughout the world, particularly in Asian, Middle Eastern, and European countries. However, cases of infection with this parasite are rarely seen in Japan. Here, we present a case of a 61-year-old woman with a solitary subcutaneous nodule in left inner aspect of the thigh, from which a long, slender, whitish worm was surgically removed. The parasite was histopathologically identified as S. mansoni. Serological testing confirmed cure of the infection after surgical removal of the parasite. The authors advocate immunoserological examination in case of S. mansoni.

Expression of milk fat globule epidermal growth factor-VIII may be an indicator of poor prognosis in malignant melanoma.

BACKGROUND: Milk fat globule epidermal growth factor-VIII (MFG-E8) is a secreted protein that binds phosphatidylserine and promotes apoptotic cell ingestion by phagocytes, mediating the immune tolerance and maintenance of homeostasis. A recent study has shown that MFG-E8 expression in human melanoma is increased with tumour progression; however, the effect of its expression on patient survival has not yet been clarified. OBJECTIVE: To analyse MFG-E8 expression in melanoma, and to determine whether it can serve as a marker for diagnosis, tumour progression and/or prognosis. METHODS: MFG-E8 expression was examined by immunohistochemistry in 60 primary melanomas, 22 metastatic lesions and 30 benign naevi. The following clinicopathological variables were evaluated: age, gender, histological type, tumour site, Breslow thickness, Clark's level, the presence or absence of ulceration and tumour-infiltrating lymphocytes, and survival periods. Statistical analyses were performed to assess associations and melanoma-specific survival. RESULTS: MFG-E8 expression was significantly higher in primary and metastatic melanoma than in naevus. Furthermore, it increased according to tumour progression and metastasis. Patients with MFG-E8 expression in primary tumours had significantly shorter survival periods than those without MFG-E8 expression. Univariate and multivariate analyses revealed that MFG-E8 expression was a statistically significant and independent prognostic factor. CONCLUSION: MFG-E8 expression may serve as a tumour progression marker and can predict an unfavourable prognosis in patients with melanoma.

Stromal expression of cathepsin K in squamous cell carcinoma.

BACKGROUND: Cathepsin K (CTSK), a cysteine protease with strong collagenolytic and elastolytic properties involved in extracellular matrix turnover, may be produced by neoplastic cells as well as stromal macrophages and fibroblasts. Its expression is suggested as associated with increased invasive and metastatic potential. OBJECTIVES: The aim of this study is to examine stromal expression of cathepsin K in skin tumors. METHODS: A series of 13 normal skin and 109 skin tumours, including 51 benign and 58 malignant epidermal tumours were tested for CTSK and Ki-67 expression by immunohistochemical analysis. RESULTS: Stromal CTSK expression and the tumoral Ki-67 labelling index were significantly higher in invasive squamous cell carcinoma (SCC) than in other epidermal tumours. CONCLUSION: Cathepsin K-positive stromal fibroblasts may play a crucial role in SCC progression by promoting extracellular matrix degradation, thereby facilitating SCC growth and invasion into surrounding tissue and vasculature. CTSK inhibitors may be a potential novel therapeutic option to decrease SCC progression.

Immunohistochemical analysis of the mammalian target of rapamycin signalling pathway in extramammary Paget's disease.

BACKGROUND: We have previously observed that persistent activation of the serine/threonine kinase, protein kinase B (AKT) is a frequent event in extramammary Paget's disease (EMPD). AKT promotes cell proliferation by its ability to coordinate mitogenic signalling with energy- and nutrient-sensing pathways that control protein synthesis through the atypical serine/threonine kinase, mammalian target of rapamycin (mTOR). CDK2, a member of the serine/threonine kinase family of cyclin-dependent kinases, is a key regulator of G(1)-S cell cycle progression, and has recently been shown to be one of the targets of AKT. The AKT-mTOR-p70 ribosomal protein S6 kinase (p70S6K) pathway has been described in some human malignancies, but not in EMPD. OBJECTIVE: To investigate the immunohistochemical staining of the AKT-mTOR-p70S6K pathway in EMPD and to evaluate the relationships among the components. METHODS: Samples of primary EMPD tissue were subjected to immunohistological staining with phosphorylated (p)-AKT, p-mTOR, p-4E-binding protein 1 (p-4EBP1), p-p70S6K/S6K1, p-ribosomal protein S6 (p-S6) and CDK2. Ten normal skin samples served as a control. RESULTS: Of the 32 EMPD tissue samples, 29, 27, 26, 29, 26 and 32 samples were positive for p-AKT, p-mTOR, p-4EBP1, p-p70S6K/S6K1, p-S6 and CDK2 staining, respectively. All these cell signalling molecules showed higher positivity in invasive EMPD than in EMPD in situ. There were significant correlations between p-AKT, p-mTOR, p-4EBP1, p-p70S6K/S6K1 and p-S6 and CDK2. CONCLUSIONS: The activation of the AKT-mTOR-p70S6K pathway may play an important role in the pathogenesis of EMPD. The high expression of the components of the pathway was highly correlated with CDK2 expression, suggesting that the AKT/mTOR pathway may induce the malignant transition through CDK2 in EMPD. The AKT-mTOR-p70S6K pathway might be a potential therapeutic target in EMPD.

Activation of the mammalian target of rapamycin signalling pathway in epidermal tumours and its correlation with cyclin-dependent kinase 2.

BACKGROUND: The enzyme mammalian target of rapamycin (mTOR) integrates many different cellular signals to control cell growth and proliferation, protein synthesis and breakdown, and other processes. Dysregulation of mTOR is implicated in a range of human diseases, including cancers and cardiovascular disorders. To date, there has been no report on the expression of protein kinase B (AKT)/mTOR cell signalling in epidermal tumours. OBJECTIVES: This study was designed to investigate the activation of the mTOR signalling pathway in epidermal tumours and to correlate this with cyclin-dependent kinase 2 (CDK2) expression. METHODS: Immunohistological staining was performed with phosphorylated (p-) AKT, p-mTOR, p-4E-binding protein 1 (p-4EBP1), p-ribosomal protein S6 (p-S6), p-p70 ribosomal protein S6 kinase 1 (p-p70S6K1) and CDK2 in 15 cases each of seborrhoeic keratosis, actinic keratosis, keratoacanthoma and Bowen's disease (BD), and 25 cases of squamous cell carcinoma (SCC). Fifteen normal skin (NS) samples served as control. RESULTS: Among 85 tumours, 40 (47%) were positive for p-AKT, 31 (36%) for p-mTOR, 44 (52%) for p-4EBP1, 38 (45%) for p-S6, and 39 (46%) for p-p70S6K1. CDK2 immunostaining was positive in all cases of SCC and BD, and in 67% of benign tumours. All of these markers were stained much more frequently in malignant tumours than in benign tumours or NS. p-AKT, p-mTOR, p-4EBP1, p-p70S6K1 and p-S6 each showed high correlation with CDK2. CONCLUSIONS: Constitutive activation of the AKT/mTOR pathway was frequent in epidermal tumours, especially in malignant tumours. Activation was highly correlated with CDK2 expression, suggesting that the AKT/mTOR pathway may induce the malignant transition through CDK2 in epidermal tumours.

Increased expression of an epidermal stem cell marker, cytokeratin 19, in cutaneous squamous cell carcinoma.

BACKGROUND: Cytokeratin 19 (CK19) has been considered to be a putative marker for epidermal stem cells in the hair follicle bulge. Cumulative reports have shown that epidermal stem cells play an important role in skin carcinogenesis. However, to date there has been no report on the clinical alteration of the stem cells in squamous cell carcinoma (SCC). OBJECTIVES: To investigate alteration of the stem cells and proliferating cells and to assess their relationship and potential contribution to SCC. METHODS: Thirty paraffin-embedded neoplastic skin lesions, consisting of 10 cases each of actinic keratosis (AK), Bowen disease (BD) and SCC, were examined immunohistologically for CK19 and Ki-67. RESULTS: Positive reactivity for CK19 was seen in 30% of AK, 50% of BD and 80% of SCC lesions. There was significantly higher expression levels of CK19 in SCC than in AK and BD (P < 0.05). In addition, BD lesions harboured a significantly higher number of CK19-positive cells than did AK lesions (P < 0.05). There were significant differences in Ki-67 labelling indices between AK and BD and between AK and SCC (P < 0.001), but not between BD and SCC (P > 0.05). Furthermore, a serial section comparison study showed that there was a minor population of cells co-expressing CK19 and Ki-67 in a subset of the tumour cells of SCC samples. The percentage of CK19+ cells significantly correlated with that of Ki67+ cells in all examined neoplastic skin lesions. CONCLUSIONS: These results suggest that CK19 expression may be associated with the retention of stem cell characteristics or a state that is uncommitted to terminal squamous differentiation.

Differential expression of two new members of the p53 family, p63 and p73, in extramammary Paget's disease.

BACKGROUND: The proteins p53, p63 and p73 are known to be overexpressed and to play important roles in the pathogenesis of many tumours, but the expression of p63 and p73 has not previously been investigated in extramammary Paget's disease (EMPD). AIM: To investigate the potential contribution of p53, p63 and p73 in the pathogenesis of EMPD. METHODS: In total, 35 paraffin wax-embedded tissue samples from patients with EMPD were examined using immunohistochemical staining for p53, p63 and p73. RESULTS: All of the 35 EMPD specimens, including all 6 invasive EMPD and 2 metastatic lymph-node specimens, showed nuclear overexpression of both p53 and p73. The expression levels (percentage of positive cells) of p53 and p73 (90.66 +/- 12.53% and 80.20 +/- 13.07%) in EMPD were significantly higher than those of normal skin. There was a significant correlation between the expression levels of p53 and p73 in EMPD. In 29 of 35 EMPD specimens, there was no nuclear expression of p63, and weak or moderate staining was found in only 6 specimens. The expression level of p63 in EMPD was significantly less than that in normal skin. CONCLUSIONS: Our study shows that the concordant overexpression of p53 and p73 and the decreased expression of p63 may play a pivotal role in the pathogenesis of EMPD. The decreased expression of p63 may play a more important role in the pathogenesis of EMPD than the overexpression of p53 and p73.

Expression of insulin-like growth factor-1 receptor, p-AKT and p-ERK1/2 protein in extramammary Paget's disease.

BACKGROUND: The insulin-like growth factor-1 (IGF-1) receptor (R)-induced phosphatidylinositol 3-kinase (PI3K)/AKT and mitogen-activated protein kinase (MAPK)/ERK signal transduction cascade, which have critical roles in prevention of apoptosis and regulation of cell cycle progression, plays an important role in tumorigenesis. The expression of IGF-1R, AKT and ERK1/2 has been described in some human malignancies, but not in extramammary Paget's disease (EMPD). OBJECTIVES: To study the expression of IGF-1R, p-AKT and p-ERK1/2 in EMPD and to evaluate the relationships among them. METHODS: Thirty-six tissue samples of 34 patients with primary EMPD were subjected to immunohistochemical staining for IGF-1R, p-AKT and p-ERK1/2. RESULTS: Of thirty-six EMPD tissue samples, 34, 34 and 28 were positive for IGF-IR, p-AKT and p-ERK1/2 expression, respectively; 27, 23 and 17 of the 36 specimens stained positive for IGF-IR, p-AKT and p-ERK1/2 in more than half of Paget's cells, respectively. There were significant correlations between the IGF-1R and p-AKT expression as well as between IGF-1R and p-ERK1/2 expression. Taken together, these results indicate that IGF-1R is overexpressed, and AKT and ERK1/2 are frequently phosphorylated in EMPD. CONCLUSIONS: Our study shows that the expression of IGF-1R and the induction of p-AKT and the p-ERK1/2 pathway may play an important role in the pathogenesis of EMPD. The IGF-IR system might be a potential therapeutic target in EMPD.