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Dive into the research topics where Asako Ichihara is active.

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Featured researches published by Asako Ichihara.


British Journal of Dermatology | 2011

microRNA-mediated keratinocyte hyperproliferation in psoriasis vulgaris

Asako Ichihara; Masatoshi Jinnin; Keitaro Yamane; Akihiko Fujisawa; Keisuke Sakai; Shinichi Masuguchi; Satoshi Fukushima; Keishi Maruo; Hironobu Ihn

Background  Psoriasis is a chronic inflammatory skin disease characterized by intense proliferation and abnormal differentiation of keratinocytes, although the pathogenesis is still not completely clarified.


Experimental Dermatology | 2013

Hair miR-29a levels are decreased in patients with scleroderma

Risa Takemoto; Masatoshi Jinnin; Zhongzhi Wang; Hideo Kudo; Kuniko Inoue; Wakana Nakayama; Asako Ichihara; Toshikatsu Igata; Ikko Kajihara; Satoshi Fukushima; Hironobu Ihn

In the present study, we evaluated the possibility that we can utilize hair shaft miR‐29a levels as disease marker of scleroderma. Hair samples were obtained from 20 scleroderma patients, five dermatomyositis patients and 13 controls. microRNAs were purified from hairs as well as skins or sera, and miR‐29a levels were measured with quantitative real‐time polymerase chain reaction. Mean hair miR‐29a levels in scleroderma patients were significantly lower than those in control subjects or dermatomyositis, while expression levels of hair shaft marker keratin 34 were similar among them. There was no strong correlation among the miR‐29a levels in the hair, skin and serum of each patient, suggesting that hair microRNAs can be independent biomarkers. We found scleroderma patients with decreased miR‐29a levels had contracture of the phalanges at a significantly higher prevalence than those without. To confirm the clinical usefulness of hair microRNAs, large‐scale researches are needed in the future.


European Journal of Dermatology | 2013

Detection of hair root miR-19a as a novel diagnostic marker for psoriasis

Hiroki Hirao; Masatoshi Jinnin; Asako Ichihara; Akihiko Fujisawa; Katsunari Makino; Ikko Kajihara; Keisuke Sakai; Satoshi Fukushima; Yuji Inoue; Hironobu Ihn

BACKGROUND Objective biomarkers that reflect the diagnosis and disease activity have not been in clinical use for psoriasis. OBJECTIVES We investigated the hair root miR-19a levels, regulatory microRNA of TNF-α, and evaluated the possibility that miR-19a can be a biomarker of psoriasis. MATERIALS AND METHODS microRNAs were extracted from hair roots of patients with psoriasis (n = 18) and healthy controls (n = 22). Samples from 10 atopic dermatitis patients and 4 dermatomyositis patients were also included as the disease controls. miR-19a levels were determined by quantitative real-time PCR. RESULTS Hair root levels of miR-19a were significantly up-regulated only in psoriasis compared with normal controls. In characteristics (ROC) curve analysis for hair root miR-19a, to distinguish psoriasis patients from normal subjects, the areas under curve (AUC) was 0.87. Relative miR-19a levels were inversely and significantly correlated with duration between symptom onset and the first visit to the hospital in psoriasis patients. CONCLUSIONS Our results indicated hair root miR-19a levels are effective as a disease marker.


PLOS ONE | 2015

Investigation of FOXM1 as a Potential New Target for Melanoma.

Azusa Miyashita; Satoshi Fukushima; Satoshi Nakahara; Junji Yamashita; Aki Tokuzumi; Jun Aoi; Asako Ichihara; Hisashi Kanemaru; Masatoshi Jinnin; Hironobu Ihn

Recent studies have shown that immunotherapies and molecular targeted therapies are effective for advanced melanoma. Non-antigen-specific immunotherapies such as immunocheckpoint blockades have been shown to be effective in the treatment of advanced melanoma. However, the response rates remain low. To improve their efficacy, they should be combined with antigen-specific immunotherapy. Elevated expression of the transcription factor, Forkhead box M1 (FOXM1), has been reported in various human cancers, and it has been shown to have potential as a target for immunotherapy. The purpose of this study was to investigate the FOXM1 expression in human melanoma samples and cell lines, to evaluate the relationship between the FOXM1 expression and the clinical features of melanoma patients and to investigate the association between the FOXM1 and MAPK and PI3K/AKT pathways in melanoma cell lines. We conducted the quantitative reverse transcription PCR (qRT-PCR) and Western blotting analyses of melanoma cell lines, and investigated melanoma and nevus tissue samples by qRT-PCR and immunohistochemistry. We performed MEK siRNA and PI3K/AKT inhibitor studies and FOXM1 siRNA studies in melanoma cell lines. We found that FOXM1 was expressed in all of the melanoma cell lines, and was expressed in 49% of primary melanomas, 67% of metastatic melanomas and 10% of nevi by performing immunohistochemical staining. Metastatic melanoma samples exhibited significantly higher mRNA levels of FOXM1 (p = 0.004). Primary melanomas thicker than 2 mm were also more likely to express FOXM1. Patients whose primary melanoma expressed FOXM1 had a significantly poorer overall survival compared to patients without FOXM1 expression (p = 0.024). Downregulation of FOXM1 by siRNA significantly inhibited the proliferation of melanoma cells, and blockade of the MAPK and PI3K/AKT pathways decreased the FOXM1 expression in melanoma cell lines. In conclusion, FOXM1 is considered to be a new therapeutic target for melanoma.


Journal of Dermatology | 2014

miR-424 levels in hair shaft are increased in psoriatic patients

Yasuo Tsuru; Masatoshi Jinnin; Asako Ichihara; Akihiko Fujisawa; Chikako Moriya; Keisuke Sakai; Satoshi Fukushima; Hironobu Ihn

Objective diagnostic markers have not been in clinical use for psoriasis. In this study, we investigated the levels of miR‐424 in hair roots and hair shafts in psoriatic patients, and evaluated the possibility that miR‐424 can be a biomarker of the disease. A single hair root and five pieces of hair shafts (~5 cm in length) were obtained from the non‐lesional occiput of each individual of 26 psoriatic patients. Control hair samples were collected from nine normal subjects. Samples from 10 atopic dermatitis patients were also included as the disease control. miR‐424 levels were determined by quantitative real‐time polymerase chain reaction. Hair shaft miR‐424 levels were significantly upregulated only in patients with psoriasis compared with normal controls and those with atopic dermatitis. By receiver–operator curve analysis of hair shaft miR‐424 to distinguish psoriatic patients from normal subjects, the area under the curve was 0.77. However, relative miR‐424 levels were not correlated with disease activity markers including disease duration, body surface area and Psoriasis Area and Severity Index. Hair root miR‐424 was not useful for evaluating both diagnosis and severity of the disease. Our results indicated hair shaft miR‐424 levels may be useful as a diagnostic marker of psoriasis.


Journal of Dermatological Science | 2014

Analysis of expression pattern of serum microRNA levels in patients with psoriasis

Yusaku Koga; Masatoshi Jinnin; Asako Ichihara; Akihiko Fujisawa; Chikako Moriya; Keisuke Sakai; Satoshi Fukushima; Yuji Inoue; Hironobu Ihn

alysis of expression pattern of serum icroRNA levels in patients with psoriasis seen only in miR-125b levels between normal subjects and AD patients (P = 0.0032). When receiver operating characteristics (ROC) curves of all 6 miRNA levels were analyzed, the serum levels of miR-203, miRNA which is most significantly downregulated in PV patients as described above, might serve as more useful biomarker for differentiating PV patients and normal subjects with the areas under curves (AUCs) of 0.92 than levels of other 5 miRNAs (Fig. S1): according to the Youden index, the most optical ywords: ammatory skin diseases; Epigenetics; croRNA


European Journal of Dermatology | 2014

Down-regulation of microRNA-196a in the sera and involved skin of localized scleroderma patients

Takamitsu Makino; Masatoshi Jinnin; Mitsuhiko Etoh; Keitaro Yamane; Ikko Kajihara; Katsunari Makino; Asako Ichihara; Toshikatsu Igata; Keisuke Sakai; Satoshi Fukushima; Hironobu Ihn

BackgroundLocalized scleroderma (LSc) exhibits fibrosis of the skin and subcutaneous tissue. LSc shows an excessive deposition of type 1 collagen.ObjectivesTo elucidate the mechanism of type 1 collagen overexpression in LSc, we investigated the epigenetics, focusing on microRNA (miRNA).Materials & MethodsmiRNA expression profile was determined by PCR array analysis. The expression of microRNA-196a (miR-196a) in the skin tissuewas examined by in situ hybridization or real-time PCR. The serum levels of miR-196a were measured by real-time PCR.ResultsPCR array analysis demonstrated that the miR-196a level was markedly decreased in LSc skin tissue in vivo. The transfection of specific inhibitor for miR-196a into normal cultured human dermal fibroblasts led to the up-regulation of type 1 collagen protein in vitro. Furthermore, the serum levels of miR-196a were significantly decreased in LSc patients.ConclusionDown-regulation of miR-196a and subsequent overexpression of type 1 collagen in dermal fibroblasts may play a key role in the pathogenesis of LSc. The serum levels of miR-196a may be useful as a diagnostic marker of LSc.


Journal of Dermatology | 2014

Case of disseminated cutaneous Mycobacterium chelonae infection mimicking cutaneous vasculitis.

Asako Ichihara; Masatoshi Jinnin; Satoshi Fukushima; Yuji Inoue; Hironobu Ihn

Mycobacterium chelonae is a non‐tuberculous, rapidly growing mycobacteria and is widely distributed in the natural environment. In the immunocompetent status, localized cutaneous infections such as cellulitis and subcutaneous abscesses commonly occur after traumatic injury. However, disseminated cutaneous infections occur on a background of immunosuppression. Cutaneous M. chelonae infection presents with a variety of skin eruptions. We report a case of disseminated M. chelonae infection mimicking cutaneous vasculitis. The patient was treated with long‐term oral corticosteroids and injected etanercept for the treatment of rheumatoid arthritis and asthma. Because the skin eruptions were preceded by asthma and rheumatoid arthritis and the pathological findings showed fibrinoid necrosis around the vascular of dermis, cutaneous vasculitis was first suspected. The culture from the pus revealed the bacterium which grew within 5 days on Ogawas culture medium suggesting a rapidly growing mycobacteria. This bacterium was identified as M. chelonae by the DNA–DNA hybridization method. We chose 800 mg/day clarithromycin and 500 mg/day levofloxacin as a result of the drug‐sensitivity test. After 6 months of the treatment, infection symptoms disappeared. Rapidly growing mycobacteria should be considered in the differential diagnosis of infections in patients under immunosuppression caused by diseases or drugs such as corticosteroids and biologic agents. Repeated bacterial examinations are important and required for the diagnosis of rapidly growing mycobacteria.


European Journal of Dermatology | 2015

Serum miR-124 up-regulation as a disease marker of toxic epidermal necrolysis

Shoki Sato; Asako Ichihara; Masatoshi Jinnin; Yuki Izuno; Satoshi Fukushima; Hironobu Ihn

BackgroundToxic epidermal necrolysis (TEN) is a lethal complication of drugs, thus early diagnosis and treatment are important. However, there are no satisfactory clinical biomarkers of TEN.ObjectivesWe investigated miR-124 and miR-214 expressions in serum and skin tissues of severe drug eruptions to evaluate the possibility of biomarkers of TEN.Materials & MethodsmicroRNAs were extracted from serum and skin tissues. Serum samples were obtained from 7 TEN patients, 5 Stevens-Johnson syndrome (SJS) patients, 11 erythema multiforme (EM) minor patients and 21 healthy volunteers. Skin tissues were obtained from 4 TEN patients, 3 SJS patients, 8 EM minor patients, 3 psoriasis and 3 atopic dermatitis patients. Six control skin samples were obtained. MicroRNA concentrations were determined by PCR array and real-time PCR.ResultsThe concentrations of miR-124 in sera from TEN were significantly higher than those from healthy controls. In the characteristics curve analysis of serum miR-124 for differentiating TEN patients from normal subjects, the area under curve was 0.94. The serum miR-124 concentration was strongly correlated with the erosion area and the SCORTENscale. The expression of miR-214was significantly increased in the skin of TEN.ConclusionThe serum miR-124 concentration can be used as a disease activity marker for severe drug eruptions, reflecting the severity of keratinocyte apoptosis.


Drug discoveries and therapeutics | 2015

Crizotinib-associated erythema multiforme in a lung cancer patient

Soichiro Sawamura; Ikko Kajihara; Asako Ichihara; Satoshi Fukushima; Masatoshi Jinnin; Emi Yamaguchi; Hirotsugu Kohrogi; Hironobu Ihn

Crizotinib is an oral small-molecule anaplastic lymphoma kinase (ALK) tyrosine-kinase inhibitor for the treatment of ALK-positive non-small-cell lung cancer (NSCLC). A 63-year old woman with postoperative relapsed ALK-positive NSCLC was treated with crizotinib. Erythema multiforme (EM) occurred one week after initiation of crizotinib therapy. Skin biopsy specimen showed compatible drug eruption. The discontinuation of crizotinib improved her eruption within one week. This report presented the first case of crizotinib-associated EM, which is the preclinical stage of Stevens-Johnson syndrome. Although crizotinib is clinically available, we should be aware of its potential severe skin adverse event.

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