Effect of chemical peeling on photocarcinogenesis.

Chemical peeling is one of the dermatological treatments available for certain cutaneous diseases and conditions or improvement of cosmetic appearance of photo-aged skin. We assessed the photo-chemopreventive effect of several clinically used chemical peeling agents on the ultraviolet-irradiated skin of hairless mice. Chemical peeling was done using 35% glycolic acid dissolved in distilled water, 30% salicylic acid in ethanol, and 10% or 35% trichloroacetic acid in distilled water at the right back of ultraviolet-irradiated hairless mice every 2 weeks for glycolic acid, salicylic acid and 10% trichloroacetic acid, and every 4 weeks for 35% trichloroacetic acid for a total of 18 weeks after the establishment of photo-aged mice by irradiation with ultraviolet B range light three times a week for 14 weeks at a total dose of 6.66 J/cm(2) . Tumor formation was assessed every week. Skin specimens were taken from treated and non-treated area for evaluation under microscopy, evaluation of p53 expression and mRNA expression of cyclooxygenase-2. Serum level of prostaglandin E(2) was also evaluated. All types of chemical peeling reduced tumor formation in treated mice, mostly in the treated area but also in the non-treated area. Peeling suppressed retention of p53-positive abnormal cells and reduced mRNA expression of cyclooxygenase-2 in treated skin. Further, serum prostaglandin E(2) level was decreased in chemical peeling treated mice. These results indicate that chemical peeling with glycolic acid, salicylic acid and trichloroacetic acid could serve tumor prevention by removing photo-damaged cells.

Preventive effect of chemical peeling on ultraviolet induced skin tumor formation.

BACKGROUND: Chemical peeling is one of the dermatological treatments available for certain cutaneous diseases and conditions or improvement of cosmetic appearance of photoaged skin. OBJECTIVES: We assessed the photochemopreventive effect of several clinically used chemical peeling agents on the ultraviolet (UV)-irradiated skin of hairless mice. METHODS: Chemical peeling was done using 35% glycolic acid dissolved in distilled water, 30% salicylic acid in ethanol, 10% or 35% trichloroacetic acid (TCA) in distilled water at the right back of UV-irradiated hairless mice every 2 weeks in case of glycolic acid, salicylic acid, and 10% TCA and every 4 weeks in case of 35% TCA for totally 18 weeks after the establishment of photoaged mice by irradiation with UVA+B range light three times a week for 10 weeks at a total dose of 420 J/cm(2) at UVA and 9.6 J/cm(2) at UVB. Tumor formation was assessed every week. Skin specimens were taken from treated and non-treated area for evaluation under microscopy, evaluation of P53 expression, and mRNA expression of cyclooxygenase (COX)-2. Serum level of prostaglandin E(2) was also evaluated. RESULTS: All types of chemical peeling reduced tumor formation in treated mice, mostly in the treated area but also non-treated area. Peeling suppressed clonal retention of p53 positive abnormal cells and reduced mRNA expression of COX-2 in treated skin. Further, serum prostaglandin E(2) level was decreased in chemical peeling treated mice. CONCLUSIONS: These results indicate that chemical peeling with glycolic acid, salicylic acid, and TCA could serve tumor prevention by removing photodamaged cells.

Successful treatment of Rosai-Dorfman disease with low-dose oral corticosteroid.

We present herein a Japanese case of Rosai-Dorfman disease (RDD) in which cutaneous manifestations completely remitted after treatment with low-dose oral corticosteroid. A 69-year-old Japanese man presented with a 1-year history of enlarged submandibular lymph nodes and subsequent nasal and pharyngeal bleeding. RDD was diagnosed based on biopsy results from a lymph node in the left parotid region. The patient had also noted several skin eruptions that repeatedly appeared and disappeared on the face and arms. Biopsies were taken from skin eruptions on the face and cuboidal fossa. Both biopsy specimens showed dense, well-demarcated infiltration of histiocytes, lymphocytes and multinucleated giant cells from just under the epidermis to the subcutaneous tissue. These histiocytes were positive for CD68 and S-100, but negative for CD1a, and some displayed emperipolesis. Given the histopathological findings and the fact that the patient was suffering from RDD, skin lesions were diagnosed as cutaneous manifestations of RDD. Cutaneous lesions gradually began to persist concomitant with enlargement of extranodal lymphadenopathy in the nasopharyngeal area. Increasing respiratory obstruction prompted a trial with oral prednisolone commencing at 0.4 mg/kg per day. Both the lymphadenopathy and skin lesions responded quickly. Within 3 months, all his skin lesions disappeared completely with almost complete resolution of lymphadenopathy. Twelve months after the beginning of oral prednisolone therapy, slight recurrence of mucosal and cutaneous lesions appeared, but disappeared quickly with an increase in prednisolone to 0.3 mg/kg per day. Low-dose prednisolone appeared very effective in the case of RDD.

Docetaxel: a therapeutic option in the treatment of cutaneous angiosarcoma: report of 9 patients.

BACKGROUND: Effective treatment options are limited for patients with cutaneous angiosarcoma (AS). Docetaxel, a member of the taxane family of drugs, reportedly has been effective in the treatment of lung, head and neck, and breast cancers. Another taxane drug, paclitaxel, reportedly had unique activity in the treatment of AS of the scalp and neck and acquired immunodeficiency syndrome-related Kaposi sarcoma. Therefore, the authors hypothesized that docetaxel may be of value in the treatment of cutaneous AS that is resistant to conventional therapy. However, there were only 3 case reports of the successful treatment of AS in elderly patients using docetaxel in combination with surgery and radiotherapy. METHODS: This was a retrospective trial. After written informed consent was obtained, docetaxel was administered intravenously at a dose of 25 mg/m(2) for 1 hour weekly over a period of 8 weeks on the basis of previous reports. This treatment regimen was received by 9 patients with cutaneous AS who were treated at Kobe University Hospital between January 2003 and October 2006. RESULTS: Six of the 9 patients who received treatment achieved major responses, including 2 complete responses and 4 partial responses. Neutropenia and peripheral neuropathy were not prominent, although severe radiation dermatitis enhanced by the docetaxel was observed in 3 patients. There were no deaths attributable to this therapy. CONCLUSIONS: The current study demonstrated that docetaxel was effective in patients with cutaneous AS.

Lub1 participates in ubiquitin homeostasis and stress response via maintenance of cellular ubiquitin contents in fission yeast.

Ubiquitin-dependent proteolysis plays a pivotal role in stress responses. To investigate the mechanisms of these cellular processes, we have been studying Schizosaccharomyces pombe mutants that have altered sensitivities to various stress conditions. Here, we showed that Lub1, a homologue of Ufd3p/Zzz4p/Doa1p in budding yeast, is involved in the regulation of ubiquitin contents. Disruption of the lub1+ gene resulted in monoubiquitin as well as multiubiquitin depletion without change in mRNA level and in hypersensitivity to various stress conditions. Consistently, overexpression of genes encoding ubiquitin suppressed the defects associated with lub1 mutation, indicating that the phenotypes of the lub1 mutants under stress conditions were due to cellular ubiquitin shortage at the posttranscriptional level. In addition, the lub1-deleted cells showed aberrant functions in ubiquitin/proteasome-dependent proteolysis, with accelerated degradation of ubiquitin. Also Cdc48, a stress-induced chaperon-like essential ATPase, was found to interact with Lub1, and this association might contribute to the stabilization of Lub1. Our results indicated that Lub1 is responsible for ubiquitin homeostasis at the protein level through a negative regulation of ubiquitin degradation.