瘢痕疙瘩不同部位P53的表达及其意义

目的观察瘢痕疙瘩浸润部、增生部和老化部P53蛋白表达差异,以探讨瘢痕疙瘩呈浸润性生长的机理。方法取手术切除的瘢痕疙瘩组织及正常皮肤各16例为标本,对其行P53蛋白免疫组织化学染色,比较瘢痕疙瘩不同病理部位和正常皮肤P53表达差异。结果瘢痕疙瘩浸润部P53表达明显高于增生部、老化部和正常皮肤（P＜0.01）,瘢痕疙瘩增生部P53表达明显高于老化部和正常皮肤（P＜0.01）,而后两者间表达差异无统计学意义（P＞0.05）。结论瘢痕疙瘩不同部位P53的表达差异可能是导致瘢痕疙瘩呈浸润性生长的机理之一。     

Proteomic analysis between pathological scars and normal skin

AIM: To investigate and screen the sensitive proteins in the formation mechanism of pathological scars by comparing the results of differential proteomic analysis between pathological scars and normal skin.METHODS: Two-dimensional gel electrophoresis was used to detect the protein expression profiles in 8 keloid patients, 8 hypertrophic scar patients and 3 matched normal skin patients.The proteins that showed differential expression of over 4-fold change were cut and analyzed by MALDI-TOF/TOF mass spectrometry.RESULTS: A two-dimensional protein profiling comparison between pathological scars and normal skin was successfully established.On average, 2 978 spots in keloid, 2 975 spots in hypertrophic scar and 3 053 spots in normal skin were identified using gel analysis software.Compared with normal skin, there were totally 36 differentially-expressed proteins in keloid and hypertrophic scar identified from the spots of over 4-fold change, including 16 proteins in both keloid and hypertrophic scar (8 up-regulated and 8 down-regulated), 11 only in keloid (9 up-regulated and 2 down-regulated) and 9 only in hypertrophic scar (4 up-regulated and 5 down-regulated).CONCLUSION: Proteomic analysis can identify the proteins with variance of pathological scars versus normal skin, thus providing probable new clues to reveal the formation mechanism of pathological scars.     

Leaf Extract of Aerva javanica Suppresses Excessive Growth of Granulation Tissue in Horses

Wound healing in horses is complicated by the excessive growth of granulation tissue, commonly known as proud flesh and is similar to keloids in human beings. At present, there is no satisfactory treatment for proud flesh in horses. In this study, we, for the first time, demonstrated that leaf extract of Aerva javanica suppresses excessive growth of granulation tissue in horses. Many plant flavonoids are claimed to have antiproliferative properties. Kaempferol is a natural flavonoid containing 3-hydroxy flavone backbone found in many plants in its aglycone form and attached with various sugars. Ecdysteroids are steroidal analogs of invertebrate steroidal hormones found in plants. Both flavonoids and ecdysteroids accumulate more in plants during abiotic stress. We hypothesized that Aerva javanica may have high levels of ecdysteroids and kaempferols for surviving in stressful conditions of desert. Those kaempferols may suppress the growth of granulation tissue by their antiangiogenesis property. Ecdysteroids may control the larvae of habronema if associated with proud flesh. Extract was prepared using solvent-based fractionation and silica gel column flash chromatography. Application of the leaf extract in horses suppressed growth of granulation tissue along with restoration of normal skin function. Various purification steps and mass spectrometry were used to identify the active components in the study.     

Effects of tripterine on viability and apoptosis of keloid fibroblasts by regulating GINS2

AIM To explore the effects of tripterine on the viability and apoptosis of keloid fibroblasts （KFB） and its molecular mechanism. METHODS The KFB were treated with tripterine at low, medium and high doses. The cell viability and apoptosis were measured by CCK-8 assay and flow cytometry, respectively. RT-qPCR and Western blot were applied to determine the expression of GINS complex subunit 2 （GINS2）. The KFB were divided into si-NC group, si-GINS2 group, Exp+pcDNA group and Exp+pcDNA-GINS2 group, and the changes of cell viability and apoptosis were measured using the above methods. RESULTS After treatment with tripterine, the viability of KFB was decreased, the apoptotic rate was increased, and GINS2 expression was decreased in a dose-dependent manner （P<0.05）. After knockdown of GINS2, the viability of KFB was decreased, and the apoptotic rate was increased （P<0.05）. Over-expression of GINS2 partially reversed the effect of tripterine on the viability and apoptosis of KFB （P<0.05）. CONCLUSION Tripterine inhibits KFB viability and promotes the apoptosis by down-regulating GINS2.     

NF-κB activation in keloid fibroblasts stimulated with TNF-α

AIM: To investigate NF-κB p65 activation and IκB-α expression in keloid fibroblasts (KFB) and normal skin fibroblasts (NSF) stimulated with TNF-α and to explore the underlying molecular pathogenesis of keloid formation. METHODS: Primary KFB was cultured. The location of NF-κB p65 and IκB-α in KFB and NSF at quiescent condition and the nuclear translocation of NF-κB p65 after TNF-α stimulation were observed by immunofluorescence technique. NF-κB p65 DNA binding activity was detected with TransAMTM NF-κB p65 kit. The IκB-α protein level was determined by means of Western blotting technique. RESULTS: After stimulated with TNF-α, NF-κB p65 translocated into the nucleus. NF-κB p65 DNA binding activity increased to its maximum at 1 h and was dropped to normal at 4 h. TNF-α induced most degradation of IκB-α at 15 min and became detectable in cytoplasm after 4 h. KFB showed more sensitive ability to TNF-α stimulation than NSF. CONCLUSION: NF-κB may play a role in keloid pathogenesis.     

Effects of GSK-3β knockdown by RNA interference on formation of keloid in vitro

AIM: To study the suppressive effect of glycogen synthase kinase-3β (GSK-3β) knockdown by RNA interference on the formation of keloid. METHODS: Human keloid fibroblasts (KFB) in vitro were transfected with 3 pairs of specific GSK-3β small interfering RNA (siRNA). The best siRNA to inhibit the GSK-3β expression in human KFB was screen by RT-PCR and Western blot. The expression of GSK-3β and related proteins at mRNA and protein levels in the KFB was determined by RT-PCR and Western blot.RESULTS: The GSK-3β siRNA1434 remarkably inhibited the expression of GSK-3β at mRNA and proteins levels in the human KFB. After transfection with GSK-3β siRNA, the protein levels of β-catenin, p-GSK-3β, Wnt2 and cyclin D1 were all decreased. KFB growth became slow. With the extension of time, the inhibition of cell growth increased, and the cell doubling time was significantly delayed. CONCLUSION: siRNA targeting GSK-3β efficiently knocks down the expression of GSK-3β in the human KFB, and inhibits the activation of Wnt signaling pathway, thus inhibiting the growth of keloid. GSK-3β may be a potential therapeutic target for keloid.