Caveolin-1 regulates osteoclast differentiation by suppressing cFms degradation

Caveolae are flask-shaped cell-surface membranes, which consist of cholesterol, sphingolipids and caveolin proteins. In a microarray analysis, we found that caveolin-1 (Cav-1) was upregulated by receptor activator of NFkappaB ligand (RANKL), the osteoclast differentiation factor. Silencing of Cav-1 inhibited osteoclastogenesis and also decreased the activation of mitogen-activated protein kinase and the induction of NFATc1 by RANKL. Cav-1 knockdown suppressed the expression of cFms and RANK, two major receptors for osteoclastogenesis. Interestingly, cFms expression was decreased only at the protein level, not at the messenger RNA (mRNA) level, whereas RANK expression was decreased at both the mRNA and protein levels. Furthermore, Cav-1 deficiency increased the lysosomal degradation of cFms. Taken together, these results demonstrate that Cav-1-dependent cFms stabilization contributes to efficient osteoclastogenesis.

A Case of Pityriasis Rotunda Aggravated During Pregnancy / 대한피부과학회지

Pityriasis rotunda is an uncommon dermatosis characterized by asymptomatic, multiple, widely distributed, strikingly circular hypopigmented or hyperpigmented, scaly patches on the trunk and extremities. Histopathologic findings are consistent with ichthyosis vulgaris. It has been associated with a variety of underlying systemic diseases. We report a case of pityriasis rotunda aggravated during pregnancy.

Immunohistochemical Labeling of Melanocytic Differentiation Antibodies in Melanocytic Nevi and Malignant Melanomas / 대한피부과학회지

BACKGROUND: Malignant melanoma is the cancer derived from melanocyte and its prevalence and mortality has increased constantly. Recently, newly developed monoclonal antibodies such as antibodies to MART-1, tyrosinase, TRP-1, MITF and NKI-beteb are frequently used in the diagnosis of melanoma. OBJECTIVE: We evaluated these antibodies to see if there are differences of positivity and expression pattern of immunohistochemical labelings between melanocytic nevi and malignant melanomas. METHODS: We have examined 6 antibodies (antibody to S-100, tyrosinase, TRP-1, MART-1, MITF and HMB-45) in their expressions in 8 malignant melanomas and 24 benign melanocytic nevi. RESULTS: No remarkable difference in positivity of staining between benign melanocytic nevi and malignant melanomas was observed. The staining pattern for S-100 protein is homogenous in all melanocytic nevi and malignant melanomas. HMB-45 showed staining confined to the junctional and superficial dermal components in both diseases. Tyrosinase and TRP-1 showed staining confined to the junctional and superficial dermal cells in most benign melanocytic nevi and variable in malignant melanomas. Although more variable patterns were found in the malignant melanomas, MART-1 demonstrated homogenous staining of all cells in the benign lesions. The staining pattern of MITF in melanocytic nevi was principally in junctional and superficial dermal components, whereas it was homogenous in malignant melanomas. CONCLUSIONS: It should be stated that none of the melanocytic differentiation antibodies has any diagnostic value in differentiating between melanoma and nevus cells, but new monoclonal antibodies taken together could contribute to the detection of malignant melanoma due to their high specificity and complementary natures.

A Case of Sweet's Syndrome which Mimic Panniculitis Treated with High Dose Potassium Iodide / 대한피부과학회지

Sweet's syndrome, first described in 1964 by Sweet, is characterized by fever, neutrophilic leukocytosis, sudden onset of asymmetric, erythematous, often painful skin lesions, and dense dermal infiltrates of mature neutrophils without signs of vasculitis. The disease responds rapidly to systemic therapy with corticosteroids but recurs in about 25% of the cases. Alternative treatments include potassium iodide, colchine, dapsone, clofazimine, cyclosporin. We report a case of classic sweet's syndrome which was successfully treated with potassium iodide without adverse reactions. 33 year-old male patient became afebrile and symptom free within 24h after starting potassium iodide 900mg/day. The cutaneous eruptions subsided completely in 5 days. He received the drug only for 12days, but there has been no recurrence after 6 months under observation.