Effect and mechanism of tacrolimus on melanogenesis on A375 human melanoma cells / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Topical tacrolimus has been used for vitiligo as a common treatment option for more than ten years while the underlying mechanism is still uncertain. The aim of this study was to investigate the direct effects of tacrolimus on the melanogenesis and migration on human A375 melanoma cells. The expression of c-KIT mRNA and protein of human A375 cells were also investigated.</p><p><b>METHODS</b>The cultured A375 human melanoma cells were randomly assigned to control and tacrolimus treatment groups (10, 10(2), 10(3) and 10(4) nmol/L). The cell proliferation was measured with Cell Counting Kit-8 assays. Melanin content was measured with NaOH method. Transwell migration assay was used to measure cell migration. The expression of c-KIT mRNA and protein were measured with real-time fluorescence quantitative polymerase chain reaction and immunohistochemistry respectively.</p><p><b>RESULTS</b>The cell proliferation of the 10(3) and 10(4) nmol/L tacrolimus groups were significantly lower (0.666 ± 0.062 and 0.496 ± 0.038) as compared with the control (0.841 ± 0.110, P < 0.05). The mean melanin content in all groups treated with different concentration of tacrolimus (10, 10(2), 10(3), 10(4) nmol/L) increased compared with the control group (P < 0.05). Dose-dependent increase in cell migration were seen in all tacrolimus-treated groups (P < 0.01). The expression of c-KIT mRNA level in A375 cells exposed to tacrolimus (10(3) and 10(4) nmol/L) had significantly increased by 3.03-fold and 3.19-fold respectively compared with the control (P < 0.05).</p><p><b>CONCLUSIONS</b>Although tacrolimus had no effects on cell proliferation on A375 human melanoma cells, it could increase the melanin content and cell migration. The expression of c-KIT mRNA and protein increased dose-dependently in tacrolimus-treated groups as compared with the control. Our study demonstrated that tacrolimus could enhance the melanogenesis and cell migration on A375 cells.</p>

Prevalence of vitiligo in China:an epidemiological survey in 6 provinces / 中华皮肤科杂志

Objective To investigate the prevalence of vitiligo in China through a multi-center and larse-population epidemiological survey.Methods A community-based survey was conducted in 6 cities from 6 provinces.Cluster sampling method was used.Subjects were required to fulfill the self-report questionnaires and received physical examination by dermatologists.EpiData and SPSS11.5 were utilized for statistical analysis. Results Totally,19 974 patients participated in this study,and 17 345 valid questionnaires were retrieved with a return rate of 86.84%.Of them,122 were found to have vitiligo.The prevalence and standardized prevalence of vitiligo was 0.70% and 0.56% in all patients,0.95% (75) and 0.69% in male patients and 0.50% (47) and O.45% in female patients.respectively.A significant elevation was observed in the prevalence of vitiligo in males than in females (P<0.01).The prevalence of vitiligo was increased with age and peaked in patients aging from 60 to 69 years and those over 70 years.The age at onset of vitiligo varied from 0 to 19 years in 21.85% of these patients,from 20 to 49 years in 47.05%.The most connnon type was focal vitiligo,which accounted for 36.06%,while the rarest type wag segmental type (2.46%).The pesitivity rate of family history of vitiligo was 9.84% in patients and 1.31% in community population (P<0.01).About 31.97% of the patients complained of negative influence of vitiligo on quality of life.Conclusions The standardized prevalence of vitiligo is 0.56%in 6 provinces from China.Males seem to have a higher prevalence of vifiligo than females.