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Biomedical subjects

S Arase

Publications and source records attributed to S Arase.

At least 19 recordsLinked to original sources
PubMed2006

Epigenetic abnormalities in cutaneous squamous cell carcinomas: frequent inactivation of the RB1/p16 and p53 pathways.

BACKGROUND: Aberrant methylation of CpG islands in the promoter regions of cancer-related genes has been demonstrated in many human tumours. However, the methylation profile of these regions in cutaneous squamous cell carcinomas (SCCs) has not been well studied. OBJECTIVES: To examine epigenetic abnormalities of a wide range of cancer-related genes in SCCs. METHODS: We investigated the methylation status of 11 candidate cancer-related genes (CDH1, p16(INK4a), p14(ARF), DAPK1, MGMT, RB1, RASSF1, p15(INK4b), PTEN, PRDM2 and p53) in 20 cases of SCC by methylation-specific polymerase chain reaction, and comparatively examined the protein production of E-cadherin (CDH1), p16, RB1, p14, BMI1 and cyclin A by immunohistochemical analysis. RESULTS: The frequency of cancer-related gene methylation in SCCs was: CDH1 (95%), p16 (20%), p14 (15%), DAPK1 (15%), MGMT (15%), RB1 (5%), RASSF1 (5%), p15 (0%), PTEN (0%), PRDM2 (0%) and p53 (0%). Almost all cases with hypermethylation of CDH1, p16, RB1 and p14 showed no obvious production of each protein, suggesting that promoter hypermethylation of these genes contributes to the loss of protein production. The results of methylation analysis, in combination with the results of our previous mutation analysis of CDKN2A locus and p53, revealed that 70% of SCCs have alterations in the RB1/p16 or p53 pathway. CONCLUSIONS: Our findings indicate that the promoter hypermethylation of cancer-related genes, especially CDH1, is frequently shown in SCCs, and dysregulation of the RB1/p16 and/or p53 pathway through either genetic or epigenetic mechanisms, except for epigenetic abnormalities of p53 itself, should contribute to the carcinogenesis of SCCs.

Aged↗
PubMed2005

Bowen's disease on the sole: p16INK4a overexpression associated with human papillomavirus type 16.

We report a case of Bowen's disease on the sole presenting clinically as an exophytic, blackish-grey, verrucous tumour, and showing human papillomavirus (HPV) type 16 on analysis with polymerase chain reaction. Positive stains for HPV particles by immunohistochemical analysis were limited to several cell nuclei at the upper stratum Malpighii. However, all the tumour cells in the epidermis exhibited strong and diffuse nuclear and cytoplasmic stains for the tumour suppressor protein p16INK4a. We speculate that dysregulation of the retinoblastoma/p16INK4a pathway may be involved in the pathogenesis of the lesion, and p16INK4a overexpression might serve as a useful surrogate marker for identifying Bowen's disease harbouring high-risk types of HPV infection.

Adult↗
PubMed2003

Differences between intrafollicular microorganism profiles in perioral and seborrhoeic dermatitis.

Although often associated with overuse of topical corticosteroids, perioral dermatitis seems to develop seldom in patients with typical seborrhoeic dermatitis in spite of long-term application of corticosteroids. In order to compare the profiles of intrafollicular microorganisms in the lesions of perioral and seborrhoeic dermatitis, tape-stripped samples were obtained from eight lesions of perioral dermatitis, 10 lesions of seborrhoeic dermatitis, and the perioral skin of 31 normal subjects. After staining with Toluidine blue, resident microorganisms on plucked hair roots were evaluated microscopically. In all patients with perioral dermatitis and two normal subjects, 20-70% of sample hairs were positive for fusiform bacteria regarded as fusobacteria. Malassezia-positive hairs were rarely seen in these cases. Seborrhoeic dermatitis showed the opposite results. Perioral dermatitis may tend to develop under fusiform-bacteria-rich conditions, rather than Malassezia-rich conditions as in the case of seborrhoeic dermatitis.

Adult↗
PubMed2002

Skin reflectance-spectra and colour-value dependency on measuring-head aperture area in ordinary reflectance spectrophotometry and tristimulus colourimetry.

BACKGROUND/AIMS: Measurement of skin colour has become increasingly popular in the study of dermatology with the increased availability of portable instruments. However, different instruments have been reported as giving different results from measurement of the same skin region. The aim of this study was to examine the effects of differences in measuring-head aperture area on skin reflectance spectra and colour values. METHODS: We measured both reflectance spectra and CIE-L*a*b* values of the skin in five different anatomical regions on 10 subjects using two MINOLTA reflectance spectrometers that were identical apart from the aperture area of the measuring heads (diameters: 5 and 11 mm). For comparison, data were also obtained from a skin-coloured tile. RESULTS: Skin reflectance values measured with the wider-aperture instrument were higher than those measured with the other, irrespective of anatomical location. The differences between the two were near zero at an incident light wavelength of 400 nm, but increased to around 10% of the reflectance value at 700 nm, increasing exponentially with incident light of increasing wavelength. Skin colour was observed to be brighter, redder and yellower, in CIE-L*a*b* expression, when measured with the wider-aperture instrument. The differences between measurements obtained from the skin-coloured tile were much smaller. CONCLUSION: Skin reflectance and colour values measured with reflectance instruments are not absolute data but depend on the aperture area of the measuring head. This is probably due to variations in the proportion of longer-wavelength light reflected from the skin and collected by the instrument.

Adult↗
PubMed2002

Graphic analysis of the relationship between skin colour change and variations in the amounts of melanin and haemoglobin.

BACKGROUND/AIMS: The L*a*b* coordinate is the most commonly used colour system to measure skin colour in dermatology and cosmetology. In this system, a* and L* are often used for quantification of the degrees of erythema and pigmentation. The aim of this study was to examine whether a* and L* can be used as specific scales to indicate the amount of haemoglobin and melanin, respectively, in the skin. METHODS: The a* and L* values were examined with a reflectance spectrometer in various skin conditions or lesions caused by a change in the amount of either melanin or haemoglobin, i.e. vitiligo, ultraviolet-induced pigmentation (PG), erythema resulting from slapping (ER), corticosteroid-induced blanching, erythema due to stasis by arm lowering, and a combination of PG and ER. The differences in values between the test sites and the adjacent normal skin, deltaa* and deltaL*, were plotted on the deltaa*-deltaL* plane and analysed statistically and geometrically. RESULTS: L* depended substantially not only on melanin but also on haemoglobin, especially if the oxygen saturation level was expected to be low. a* was also influenced by melanin. The results of graphic analysis indicated that a linear transformation of (deltaa*, deltaL*) into (deltaHb = 1.68 deltaa* + 0.60 deltaL*, deltaMel =-1.06 deltaa*-1.44 deltaL*) was suitable for separately estimating the change in the amount of haemoglobin (deltaHb) and in that of melanin (deltaMel). CONCLUSION: The results of this study may be of value for understanding the relationship between colour coordinates of the skin and the quantities of haemoglobin and melanin, and may be of use when pigmented lesions of the face are monitored by tristimulus colourimetry, as facial skin colour is affected considerably by the rich and easily variable cutaneous blood flow.

Adult↗
PubMed2001

The chemotactic effect of a dermal papilla cell-derived factor on outer root sheath cells.

The effect of cultured normal human dermal papilla cells (DPCs) and conditioned medium prepared with cultured DPCs on chemotactic migration of human hair outer root sheath cells (ORSCs) was examined quantitatively. ORSCs showed significantly increased migration toward both cultured DPCs and the conditioned medium suggesting that DPCs produce and secrete a paracrine factor(s), which attracts hair follicle epithelial cells. Some soluble factors, which are reportedly produced by DPCs, such as insulin-like growth factor-I (IGF-I), hepatocyte growth factor (HGF), vascular endothelial cell growth factor (VEGF), and transforming growth factor-beta1 (TGF-beta1), were also examined. ORSCs showed dramatically increased migration toward IGF-I and HGF at concentrations of 1-10 ng/ml. On the other hand, neither VEGF nor TGF-beta1 showed any effect on the chemotaxis of ORSCs. It is interesting that all factors involving mitogenic activity did not always have chemotactic activity for ORSCs. This is the first report to establish that IGF-I and HGF have not only a growth stimulatory but also a chemotactic effect on ORSCs. In addition, the method presented here may help to simplify chemotaxis assays of any type of epithelial keratinocytes with poor mobility.

Cell Division↗
PubMed2001

Localized heat urticaria: a clinical study using laser Doppler flowmetry.

We studied the pathophysiology of localized heat urticaria using laser Doppler flowmetry (LDF) in two patients with this rare disease. In heat challenge tests, performed with different challenge times and temperatures, a heat stimulator with a thermoregulated metal disc was utilized. Immediately after removal of the heat source, cutaneous blood flow (CBF) changes in the tested sites were monitored with LDF. In both patients the increase in (CBF) took place at some intervals after a heat challenge, synchronous with the start of the urticarial response. This interval, or the latency time (LT), showed distinct inverse proportion to the intensity of heat stimuli and was prolonged by effective treatments, such as application of antihistamines and repeated heat exposure by LDF. Therefore, the time of latency might be regarded as a good indicator of the severity of illness and therapeutic effectiveness, and thus might reflect the relationship between the degree of heat stimuli and the releasing process of chemical mediator(s) in patients with localized heat urticaria (LHU).

Administration, Topical↗
PubMed2001

Germline mutations of the PTCH gene in Japanese patients with nevoid basal cell carcinoma syndrome.

Nevoid basal cell carcinoma syndrome (NBCCS) is an autosomal dominant disorder characterized by developmental and skeletal anomalies, palmo-plantar pits, odontogenic keratocysts, ectopic calcification, and occurrence of various types of tumors including basal cell carcinoma. Recent evidence has indicated that the human homologue of a Drosophila segment polarity gene, PTCH, is a NBCCS susceptibility gene. In the study presented here, we detected two novel mutations of the PTCH gene, I805X/2395delC and Y93X/C297A, in two unrelated Japanese patients. Early protection of the skin from the sunlight is important to the prevention of BCC development in NBCCS patients. Genetic analysis of the PTCH gene is essential for the early, definitive diagnosis of NBCCS, especially before the expression of clinical manifestations is complete.

Adult↗
PubMed2001

Minoxidil-induced hair growth is mediated by adenosine in cultured dermal papilla cells: possible involvement of sulfonylurea receptor 2B as a target of minoxidil.

The mechanism by which minoxidil, an adenosine-triphosphate-sensitive potassium channel opener, induces hypertrichosis remains to be elucidated. Minoxidil has been reported to stimulate the production of vascular endothelial growth factor, a possible promoter of hair growth, in cultured dermal papilla cells. The mechanism of production of vascular endothelial growth factor remains unclear, however. We hypothesize that adenosine serves as a mediator of vascular endothelial growth factor production. Minoxidil-induced increases in levels of intracellular Ca(2+) and vascular endothelial growth factor production in cultured dermal papilla cells were found to be inhibited by 8-sulfophenyl theophylline, a specific antagonist for adenosine receptors, suggesting that dermal papilla cells possess adenosine receptors and sulfonylurea receptors, the latter of which is a well-known target receptor for adenosine-triphosphate-sensitive potassium channel openers. The expression of sulfonylurea receptor 2B and of the adenosine A1, A2A, and A2B receptors was detected in dermal papilla cells by means of reverse transcription polymerase chain reaction analysis. In order to determine which of the adenosine receptor subtypes contribute to minoxidil-induced hair growth, the effects of subtype-specific antagonists for adenosine receptors were investigated. Significant inhibition in increase in intracellular calcium level by minoxidil or adenosine was observed as the result of pretreatment with 8-cyclopentyl-1,3-dipropylxanthine, an antagonist for adenosine A1 receptor, but not by 3,7-dimethyl-1-propargyl-xanthine, an antagonist for adenosine A2 receptor, whereas vascular endothelial growth factor production was blocked by both adenosine A1 and A2 receptor antagonists. These results indicate that the effect of minoxidil is mediated by adenosine, which triggers intracellular signal transduction via both adenosine A1 and A2 receptors, and that the expression of sulfonylurea receptor 2B in dermal papilla cells might play a role in the production of adenosine.

ATP-Binding Cassette Transporters↗
PubMed2000

Severe dermographism after topical therapy with diphenylcyclopropenone for alopecia universalis.

We describe here a 19-year-old Japanese man with an 11-year history of alopecia universalis, who, after the 1st application of a 0.003% diphenylcyclopropenone (DPCP) solution to the whole scalp, developed acute contact dermatitis at the test site, together with widespread severe dermographism. Every 3 weeks, persistence of the severe urticarial reaction and efficacy of treatment were monitored by constant pressure stimuli in a series of pressure tests, and subsequently evaluated by laser Doppler flowmetry (LDF). Although, on pressure tests, the urticarial response was found to significantly improve after starting treatment, erythematous responses continued to appear for nearly 3 months. The persistent course of these side-effects in our patient strongly suggests that precautions must currently be taken in the therapeutic use of potent sensitizers such as DPCP.

Administration, Topical↗
PubMed2000

A novel PTEN mutation in a Japanese patient with Cowden disease.

Cowden disease (CD) is an autosomal dominant syndrome characterized by multiple hamartomatous lesions and an increased risk for malignancies. Recent evidence has indicated that the PTEN gene, encoding a protein tyrosine phosphatase, is the CD susceptibility gene. However, another line of evidence has suggested that CD might be genetically heterogeneous. Clinical features of CD are variable, and there are interfamilial differences in the expression of skin lesions. Therefore, information on PTEN mutations in CD patients should be accumulated to clarify the genotype-phenotype correlation. In the present study, we found heterozygous germline mutations of PTEN in all of three Japanese patients with CD examined, indicating no genetic heterogeneity among our patients. The mutations included two non-sense mutations of R335X and R130X, and a mis-sense mutation of C136R. To the best of our knowledge, the C136R mutation has not previously been reported in CD patients. This novel mutation was located outside the core motif of the phosphatase domain of PTEN protein, where most of the missense mutations previously reported in CD patients were clustered. Mucocutaneous manifestations were far fewer in the patient with this mutation than in the patients with nonsense mutations. Whether the phenotypic difference in mucocutaneous features was due to the different mutations remains unclear.

Adult↗
PubMed1999

Sweet's syndrome associated with chronic myelogenous leukemia: demonstration of leukemic cells within a skin lesion.

We report a case of acute febrile neutrophilic dermatosis, Sweet's syndrome, associated with chronic myelogenous leukemia (CML) in which we found rearrangement of the bcr gene in DNA obtained from a skin lesion as well as in blood DNA by Southern blot analysis. This indicated the presence of CML cells within the skin lesion. To our knowledge, this is the first report in which the presence of CML cells is shown within skin lesions of Sweet's syndrome. In our patient, leukocyte alkaline phosphatase activities returned to normal levels when he was suffering from Sweet's syndrome and decreased again to below normal levels after it subsided. Whether the normalization of leukocyte alkaline phosphatase activity is common among CML patients with Sweet's syndrome remains to be determined.

Blotting, Southern↗
PubMed1999

Lack of somatic mutation in the PTEN gene in squamous cell carcinomas of human skin.

The tumor suppressor gene PTEN is deleted and/or mutated in a variety of tumors and the susceptibility gene for Cowden disease. Loss of heterozygosity of chromosome 10q23, where PTEN resides, in squamous cell carcinomas (SCCs) of human skin and the association of SCC with Cowden disease were reported previously. In the present study, we screened for mutations of PTEN in SCCs by polymerase chain reaction single strand conformation polymorphism analysis to examine whether PTEN is involved in the carcinogenesis of SCC. None of 21 SCCs showed somatic mutations in the coding regions of PTEM. Instead the same allelic variation was detected in two cases without any clinical features of Cowden disease. Our results indicate that inactivation of PTEN does not play an important role in the carcinogenesis of SCC.

Carcinoma, Squamous Cell↗
PubMed1999

Cerebriform intradermal nevus: a case of scalp expansion on the galea.

We report here a 7-year-old Japanese girl with cerebriform intradermal nevus (CIN). By placement of expanders on the galea, her scalp was expanded more easily with less discomfort than is expected when the expanders are placed under the galea. An immunohistochemical study on the expression of proliferating cell nuclear antigen suggested higher proliferative activity of nevus cells from the CIN lesion than that of cells from congenital or acquired intradermal nevi. The high proliferative activity appeared to be associated with a growth spurt of the lesion.

Child↗
PubMed1998

Psoriatic arthritis associated with dilated cardiomyopathy and Takayasu's arteritis.

A 40-year-old Japanese man with psoriatic arthritis (PA) involving the spine, sacroiliac and peripheral joints presented with dyspnoea and ankle oedema. Blood pressure was 180/110 and 114/80 mmHg in the right and left upper arms, respectively. Examinations showed left ventricular dilatation and diffuse hypokinesis of the left ventricle, with no involvement of the coronary arteries. Aortography detected total occlusion of the left subclavian artery and stenosis of the origin at the right renal artery. Dilated cardiomyopathy and Takayasu's arteritis associated with PA was diagnosed. A few cases of PA have been reported in association with cardiovascular diseases, but the association of these three diseases has not been documented in the literature to date. Dermatologists need to be aware of cardiovascular manifestations in patients with PA, because cardiovascular diseases are not rare in other seronegative spondyloarthropathies.

Adult↗
PubMed1998

Peripheral ulcerative keratitis associated with erythema elevatum diutinum and a positive rheumatoid factor: a report of three cases.

Peripheral ulcerative keratitis (PUK) is a complication of collagen-vascular diseases such as rheumatoid arthritis (RA) and other systemic vasculitides. We report three cases of erythema elevatum diutinum with PUK. These patients presented with nodules and plaques consistent with erythema elevatum diutinum on the extremities and crusted or ulcerated purpuric lesions on the soles. Histopathological examination of these lesions revealed a dense neutrophilic infiltrate with nuclear dust and fibrin around blood vessels. All the patients developed PUK concomitant with the development of the skin lesions. The rheumatoid factor was positive at high titre in all three patients; this was associated with probable RA in one. Cutaneous lesions were dramatically improved by administration of dapsone in all cases. Dapsone was also effective in treating the ocular lesions in two patients.

Aged↗
PubMed1998

An unusual reaction to cold: a sporadic case of familial polymorphous cold eruption?

A 14-year-old Japanese girl had a lifelong history of skin lesions developing after generalized exposure to cold air; the lesions were often accompanied by systemic symptoms such as fever and chills. The skin lesions were non-pruritic, maculopapular, erythematous eruptions and were neither urticarial nor angioedematous. An ice-cube test was negative. Laboratory examinations showed marked leucocytosis during an acute attack. On the basis of clinical features, histological findings and laboratory data, although these symptoms were sporadic, the most likely diagnosis was familial polymorphous cold eruption, which has also been referred to as familial cold urticaria. Serum levels of granulocyte colony-stimulating factor and interleukin 6 were significantly elevated during an acute attack after cold exposure, suggesting that both cytokines played important parts in the development of her condition.

Adolescent↗