Objective To investigate the relationship between keloid proliferation and destruction of skin appendages(SAs). Methods Pathological biopsies of keloids were derived from 17 patients whounderwent scar resection. All samples were divided into 4 groups: infiltrating growth locus of keloids（K-I,n=9），proliferative keloids (K-P,n=17), atrophic keloids (K-A,n=10), and edging normal skin (K-N,n=6). Normal skin derived from thorax of patients was used as control (NS, n=6). The density of SAs and the expressive characteristics of pan-cytokeratin (CKp), cytokeratin19 (CK19), secretory component of glandular epithelium(SC), proliferating cell nuclear antigen(PCNA), and apoptosis related proteins (Bcl-2 and Bax) were observed with immunohistochemical method. Results Compared with K-N and NS, the density of SAs expressing CKP and SC in keloids was apparently decreased, and remnant of CKp protein was observed after the disappearance of SAs structures. Protein expression of Bax was increased in epithelial cellsof most SAs. SAs containing postive immunostaining signals of Bcl-2, PCNA and CK19 exhibited squamous epithelization and abnormal structure. The structure of SAs underwent 3 morphological stages: infiltrating, proliferating, and maturing.In correspondence to each stage, SAs underwent proliferation, structural destruction, and fibrosis which were caused by cellular migration, nflammatory reaction, and vascular occlusion respectively. Conclusion Abnormal proliferation of epithelial cells and their structural destruction of SAs may beassociated with tissue fibrosis in keloid lesion.
Objective To study the expression of heat shock protein 47 (HSP47) and its correlation to collagen deposition in pathological scar tissues. Methods The tissues of normal skin(10 cases), hypertrophic scar(19 cases), and keloid(16 cases) were obtained. The expression ofHSP47 was detected by immunohistochemistry method. The collagen fiber content was detected by Sirius red staining and polarization microscopy method. Results Compared with normal skin tissues(Mean IOD 13 050.17±4 789.41), the expression of HSP47 in hypertrophic scar(Mean IOD -521 159.50±272994.13) and keloid tissues(Mean IOD 407 440.30±295 780.63) was significantly high(Plt;0.01). And there was a direct correlation between the expression of HSP47 and the total collagen fiber content（r＝0.386，Plt;0.05）. Conclusion The HSP47 is highly expressed in pathological scartissues and it may play an important role in the collagen deposition of pathological scar tissues.
Objective To study the curative effects of keloid by operation combined with postoperative β radiation and silicone gel sheeting. Methods From 1996 to 2002, 598 patients with keloid(243 males, 355 females, aging 15-55 years with an average of 28.6 years) were treated by integrated therapy. Their disease courses were from 6 months to 6 years. The keloid area ranged from 1.0 cm×1.5 cm~8.0 cm×15 cm. First, keloid was removed by operation, and then the wounds weresutured directly(group suture) or covered with skin graft(group graft). In groupsuture, the operational sites were managed by β ray radiotherapy 24-48 hours after operation. The total doses of radiation were 12-15 Gy, 5 times 1 week(group suture A) and 10 times 2 weeks (group suture B). Radiotherapy was not taken until stitches were taken out in group graft, and then the same methods were adopted as group suture B. After radiotherapy, silicone gel sheeting was used in 325 cases for 3-6 months. Results All patients were followed up for 12-18 months. (1) The overall efficacy was 91.3% in group suture A(n=196), and 95.8% in group suture B (n=383), respectively. There was significant difference between the two groups(Plt;0.01). (2) Radiotherapy was of no effect in 6 cases of group graft(n=19). (3) Silicone gel sheeting had effectivenessin 185 cases. Silicone gel sheeting had no obvious effect on the overall efficacy, but it could improve the quality of texture and color of skin. Conclusion By use of integrated methods to treat keloid, if the wound can be sutured directly, skin grafting should not be adopted. The results in group suture B are better than those in group suture A; silicone gel sheeting should be used as possible.
Objective To clarify the correlation of p53 codon 72 polymorphism in peripheral blood with keloid susceptibility in Chinese population. Methods All the literatures of case-control research on the correlation between p53 codon 72 polymorphism in peripheral blood and keloid in Chinese population were searched in PubMed, EBSCO, CNKI, CBM, and WanFang Data from their establishment to August 2010. Meta-analyses were performed to detect whether there were differences between the keloid group and the control group about the distribution of genotypes of p53 codon 72 in peripheral blood, such as, Pro/Pro vs. Arg/Arg, Pro/Pro vs. Pro/Arg, and alleles Pro vs. Arg. Results Five studies involving 328 keloid patients and 420 patients in the control group were included. The results of meta-analyses showed that the population having the genotype Pro/Pro presented no increased keloid risk compared to that with the genotypes Arg/Arg (OR=2.17, 95%CI 0.86 to 5.47) or Pro/Arg (OR=1.90, 95%CI 0.92 to 3.93), while the allele Pro showed significant association with increased keloid risk compared to the allele Arg (OR=1.86, 95%CI 1.03 to 3.35). Conclusion The allele Pro of p53 codon 72 in peripheral blood of Chinese population is significantly associated with increased keloid risk.
Objective To observe the effect of gene expression of p53 and the polymorphism of p53 gene codon 72 on cl inical phenotype of keloids. Methods The tissue and blood samples were taken from 35 patients with keloids, 19 males and 16 females, and the course of disease was from 4 months to 8 years. Meanwhile, autologous peripheral blood was collected for genotype analysis. According to the observing scope, the tissue samples of the keloids were divided into 2 groups: the central group involving the central part of the keloids (the central area within two-thirds of the radius) and the peripheral group involving the peripheral part of the keloids (the peripheral area within one-third of the radius). According to the largest diameter of the keloids, the two groups were divided into 3 subgroups: the small size group with 5 patients (lt; 1 cm), the medium size group with 21 patients (1-3 cm) and the large size group with 9 patients (gt; 3 cm). DNA of the tissue and blood samples were extracted, and the PCR followed by DNA sequencing was used to detect the polymorphism of p53 gene codon 72. The expression change of P53 was detected by immunohistochemical staining. The fibroblast apoptosis in keloid tissues was detected by TUNEL method. Results The genetic genotype of p53 gene codon 72 in keloids included Arg/Arg in 7 cases, Pro/Arg in 21 cases, Pro/ Pro in 7 cases. The significant correlation was found between genotype and cl inical phenotype (P lt; 0.05). Immunohistochemical staining revealed that P53 was detectable in peripheral and central groups of small-medium size keloids and central groups keloids, and detectable in few cells in peripheral groups of large size keloids. The absorbency value was 3 439.359 8 ± 538.527 5 in Arg/Arg genotype, 3 273.186 2 ± 375.213 9 in Arg/Pro genotype, 1 691.372 9 ± 98.989 3 in Pro/Pro genotype. There weresignificant differences among the three genotypes (P lt; 0.05). The fibroblast apoptosis was detected by TUNEL, and the apoptotic cells were evenly distributed. The apoptosis index was 31.000 0 ± 3.266 0 in peripheral group of large size keloids, 42.300 0 ± 4.354 8 in peripheral group of medium size keloids, 44.600 0 ± 5.253 6 in peripheral group of small size keloids. There were significant differences among the three groups (P lt; 0.05). Conclusion There is close relationshi p between the cl inical phenotype of keloids and the expression of P53. The polymorphism variation of p53 gene codon 2 is beneficial for apoptosis of fibroblasts in keloids.
Objective To study the mutations at 1 573 fragment of TNF receptor II (TNFR-II) gene in patients with keloid. Methods The tissue DNA was extracted from 22 samples of keloids donated by 22 patients (6 males and 16 females, aged 18-53 years), and all keloids were examined and classified by pathologist. The peri pheral blood DNA was extracted from the same patients as the control. PCR was used to ampl ify the 1 573 fragment of TNFR-II gene from the keloid tissue DNA and peripheral blood DNA. The PCR products were sequenced directly and then compared with the GeneBankdata. Results All the concentration of the extracted DNA in trial were higher than 0.50 μg/μL and the purity (A260/A280) ofthe extracted DNA were higher than 1.5. It closed to the magnitude of the design DNA fragment by agarose gel electrophoresis examining, and corresponded with the test requirement. Mutations at 1 573 fragment of TNFR-II gene were detected in 13 out of 22 keloids. The mutation incidence was 59.1%. Among them, 9 had point mutation at codon 1 663, accounting 40.9%. No TNFR-II gene mutation was detected in all peripheral blood samples. There were significant difference between keloids DNA and peripheral blood DNA (P lt;0.01). The mutations involved point mutation, deletion and insertion as well as multisite and multitype. Conclusion There is a correlation between the mutation at 1 573 fragment of TNFR-II gene and keloid.
Objective To build animal models of keloid by method of tissue engineering and to discuss the feasibility of using it in clinical and lab researches. Methods Fibroblasts(FB) were isolated from keloids and cultured. The seventh and eighth generation of the cultured FBs were inoculated into the copolymers of polylactic acid and polyglycolic PLGA. After being cultured in rotatory cell culture system （RCCS）for 1 week,the FB was transplanted into athymic mice. The specimens were obtained 4 weeks and 8 weeks and examined histologically. Results All mice survived.The collagen patterns of all keloids were pressed in every specimen obtained 8 weeks. Fibrocytes andFB were observed in specimens by electronic microscope. There were abundent rough endoplasmic reticulum (RER) in FB， which indicated that FB’s capability of synthesizing and secreting collagen was preserved and the cellular characteristicwas remained. Conclusion There is a good affinity between PLGAand FB. The composition of PLGA and FB can form keloids in athymic mice,so that it deserves further researching and developing.
OBJECTIVE: To investigate the expression and distribution of platelet derived growth factor receptor-beta(PDGFR-beta) in normal skin and keloid and to discuss its biological function in keloid formation. METHODS: 1. To detect the expression and distribution of PDGFR-beta in normal skin and keloid tissue by immunohistochemistry; 2. To detect the receptor expression in vitro by Flow cytometry (FCM); 3. To detect the subcellular distribution of receptor by Laser confocal microscope. RESULTS: 1. Immunohistochemistry showed that normal skin and keloid tissue were almost the same in expression but different in distribution of PDGFR-beta; 2. There was more expression of PDGFR-beta in normal fibroblasts than that in keloid fibroblasts in vitro by FCM; 3. Laser confocal microscope revealed that the PDGFR-beta concentrated on the surface of cell membrane in keloid fibroblasts, but in normal skin fibroblasts, the receptors were coagulated on the nuclear membrane and intranucleus. CONCLUSION: Compared with the fibroblasts in vivo, there was a difference of the PDGFR-beta expression in fibroblasts in vitro, more expression of PDGFR-beta in normal fibroblast than that in keloid fibroblast in vitro; and the subcellular distribution of PDGFR-beta was different in normal skin and keloid fibroblasts. The characteristics of the expression and distribution of PDGFR-beta in keloid may contribute to the formation of keloid.
【Abstract】 Objective To summarize the recent progress in related research on transforming growth factor β1 （TGF-β1）/Smad3 signal transduction pathway and post-traumatic scar formation. Methods Recent related literature at home and abroad on TGF-β1/Smad3 signal transduction pathway and post-traumatic scar formation was reviewed and summarized. Results TGF-β1 is an important influence factor of fibrotic diseases, and it plays biological effects by TGF-β1/Smad3 signal transduction pathway. The pathway is regulated by many factors and has crosstalk with other signal pathways at cellular and molecular levels. The pathway is involved in the early post-traumatic inflammatory response, wound healing, and late pathological scar formation. Intervening the transduction pathway at the molecular level can influence the process of fibrosis and extracellular matrix deposition. Conclusion TGF-β1/Smad3 signal transduction pathway is an important way to affect post-traumatic scar formation and extracellular matrix deposition. The further study on the pathway will provide a theoretical basis for promotion of wound healing, as well as prevention and treatment of pathological scar formation.
Objective To compare gene express difference ofkeloid and normal skin tissues by using the suppression subtractive hybridization (SSH) so asto find the differential express gene in keloid. Methods mRNA extracted fromkeloid and normal skin tissues was used as the template to synthesis cDNA of keoid and normal skin. The cDNA of keloid served as a tester, the cDNA of normal skin as a driver. cDNA was digested with RsaⅠ. Adaptor-ligated tester cDNA was prepared. Then first hybridization, second hybridization and PCR amplificationwere done. Differentially expressed cDNA was selectively amplified during thesereactions. After SSH, the PCR mixture was ligated with T-vector. The positive clones were selected and the insert gene fragments were analyzed. Southern hybridization identified the keloid differential express genes. The positive clones ofSouthern hybridization were selected, and these sequences were analyzed. The results were compared with that of GeneBank. Results Thirteen differential genes were found in keloid, of which 11 gene clones have been known their function, and 2 clones have not known their function. 〖WTHZ〗Conclusion Keloid differentially expressed gene was screened successfully by SSH.