Study The Expression Of CASK,Id1 In Human Keloid And The Effect Of Artesunate On Keloid Fibroblast

Objective To explore the difference of protein expression of CASK and Id1 in normal skin and keloid with immunohistochemical method and the change of protein expression of CASK and Id1 in fibroblasts derived from human keloid induced by Artesunate with immunocytochemical method and Western blotting so as to approach the mechanism of keloid.Methods(1) the expression of CASK and Id1 in 15 cases of keloid and 12 cases of normal skin were detected by immunohistochemical method.(2) DMEM medium was the basic culture medium,being supplemented with fetal bovine serum(10%) using for culturing keloid tissue pieces attaching to the wall of culture flask.Fibroblasts were incubated at 37℃in a humidified atmosphere of 5%CO₂ and 95% air in the incubator. Growth kinetics, Cellular morphologies were observed. Fibroblasts were treated with a series of concentrations of Artesunate,Dm screened by MTT reduction assay then experimental groups designed according to this Dm.The expression of CASK and Id1 in keloid fibroblast was detected by immunocytochemical assay.The changes of CASK and Id1 protein were detected with Western blotting.Results(1) Positive rate of CASK and Id1 expression in 14 cases keloid were 72.3% and 74.5% . Among 14 cases of normal skin, positive rate of CASK and Id1 were 18.5% and 20.4% . The difference of positive rate of CASK and Id1 expression between two groups were statistical significance(P<0.05).(2) The cell proliferation was inhibited by Artesunate.It showed that division index were decreased with dosage and time dependency in dosages of Artesunate .The IC50 of the drug against the cells was 60mg/l..Oval-shap cells, karyopyknosis and fragmentation were observed under light microscope.(3) Artesunate inhibited the proliferation of fibroblasts derived from human keloid in a time and dose dependent manner. The data indicated that the expression of CASK of fibroblasts derived from keloid was upgraded and Id1 was depressed by artesunate after 24h.The ptotein expression of CASK increase 26.0% and Id1 reduced 30.76%. The difference of positive rate of CASK and Id1 expression between two groups were statistical significance(P<0.05).Conclusion(1) The regulation CASK and Id1 in keloid suggested that CASK and Id1 may play an important role in the formation of keloid.(2) The inhibiting effect of Artesunate on proliferation of fibroblasts in a dosage and time dependent manner was manifested. The expression of CASK of fibroblasts derived from keloid was upgraded and the expression of Id1 was depressed.(3) Artesunate inhibited the proliferation in keloid fibroblast, which may be related to the change of protein expression of CASK and Id1.Through reduce the expression of Id1,Artesunate participate inhibit fibroblast proliferation.CASK, hypothesized as upstream of Id1,had the growth inhibitory effect on fibroblasts,which might be throught Id1 signal pathway.