Autocrine effect of vascular endothelial growth factor on the proliferation of HaCaT cells / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To determine the autocrine effect of vascular endothelial growth factor (VEGF) on epidermal keratinocytes HaCaT cells.</p><p><b>METHODS</b>Cultured HaCaT cells were treated with various concentrations of VEGF(165) (0,1,5,10,25,50,100 ng/ml) or Avastin (0,0.063,0.125,0.25,0.50,1.0,2.0 mg/ml) in vitro. HaCaT cell proliferation was determined by MTT assay and the cell migration was measured by migration assay. The effect of VEGF(165) (10 ng/ml) on phosphorylation of ERK1/2 was detected in HaCaT cells pretreated or not pretreated with Avastin (0.5 mg/ml).</p><p><b>RESULTS</b>VEGF enhanced the proliferation and migration of HaCaT cells in a dose-dependent manner, while Avastin inhibited the effects of VEGF also in a dose-dependent manner. VEGF(165) (10 ng/ml) induced the phosphorylation of ERK1/2 in HaCaT cells,but which was blocked by Avastin (0.5 mg/ml).</p><p><b>CONCLUSION</b>VEGF enhanced the proliferation and migration of HaCaT cells in a dose-dependent manner, while Avastin inhibited the effects of VEGF also in a dose-dependent manner. VEGF(165) (10 ng/ml) induced the phosphorylation of ERK1/2 in HaCaT cells,but which was blocked by Avastin (0.5 mg/ml).</p>

Fetal bovine serum enhances expression of PEDF in epidermal keratinocytes and dermal fibroblasts / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To investigate the effect of fetal bovine serum (FBS) on expression of pigment epithelium-derived factor (PEDF) in normal epidermal keratinocytes and dermal fibroblasts.</p><p><b>METHODS</b>Keratinocytes and fibroblasts were incubated with 10% FBS. PEDF protein level in the cells was determined by immunofluorescence and Western blot.</p><p><b>RESULTS</b>PEDF was localized mostly in the cytoplasm,while some in the nuclei. The distribution of PEDF in cytoplasm was in a granular pattern. 10% FBS increased the expression of PEDF both in keratinocytes and fibroblasts,but histamine and Phorbol 12-myristate 13-acetate (PMA) did not interfere the distribution of PEDF in cells.</p><p><b>CONCLUSION</b>10% FBS can upregulate expression of PEDF in epidermal keratinocytes and dermal fibroblasts.</p>

Biological characterization of cultured dermal papilla cells and hair follicle regeneration in vitro and in vivo / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Dermal papilla cells (DPC) are a group of mesenchyme-derived cells at the base of the hair follicle, where they regulate and control hair follicle growth through the expression and secretion of cytokines. Nevertheless, the role of DPC derived chemokines and other cytokines in the hair follicle biology remain speculative. In this study, we investigated the expression of basic fibroblast growth factor (bFGF), endothelin-1 (ET-1) and stem cell factor (SCF) in different passages of cultured DPC and their effects on the biological behaviour of DPC.</p><p><b>METHODS</b>The expression of bFGF, ET-1 and SCF in different passages of cultured DPC and their possible effects on the biological behavior of DPC are investigated using in situ hybridization and immunochemistry. In addition, we performed transplantation of hair follicle cells into nude mice. The cultured DPC, dermal sheath cells and fibroblast of human scalp, respectively, were mixed with cells of the hair follicle epithelium in different ratios, and then were cultured in hair follicle organotypic cultures or implanted into the subcutis of nude mice.</p><p><b>RESULTS</b>The expression of ET-1 and SCF in early passages of cultured DPC became stronger, but turned weaker and even negative in late passages (> 6 passages). Hair follicle-like structures were formed after DPC combined with the cells of hair follicle epithelium cells in hair follicle organotypic cultures. When hair follicle organotypic cultures were implanted into the subcutis of nude mice, the relative intact hair follicles were formed. After the transplantation of hair follicle cells into the nude mice, the hair follicle-like structure was formed in the group that contained DPC mixed with hair follicle epithelium cells. However, no hair follicles were formed in the other two groups. It was found that the higher the expression of ET-1 and SCF in DPC, the stronger the ability of DPC to induce hair follicle regeneration.</p><p><b>CONCLUSIONS</b>The cultured DPC can induce hair follicle regeneration and sustain hair growth in vivo and in vitro. Moreover, the expression of ET-1 and SCF is correlated with the ability of DPC inducing hair follicle regeneration.</p>

Effects of acitretin on the expression of signaling pathway-related genes in epidermal squamous-cell carcinoma cells / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To study the effects of acitretin on the expression of signaling pathway-related genes in an epidermal squamous-cell carcinoma cell line.</p><p><b>METHODS</b>The mRNA expression levels of STAT3, cyclin D1 and p42/44MAPK were detected in a human epidermal carcinoma cell line A431 by RT-PCR. Their expressions at protein level were studied by Western blot. The expression levels were studied in cells treated with or without 10(-5) mol/L acitretin at different time intervals.</p><p><b>RESULTS</b>(1) Acitretin could significantly inhibit the expression of STAT3 and cyclin D1 mRNA in a time-dependent manner (P < 0.05). The STAT3 and cyclin D1 protein expression levels were down-regulated. Acitretin could also down-regulate the p42/4MAPK mRNA expression. (2) After incubation with acitretin, the mRNA level of cyclin D1 cells was positively correlated with that of STAT3 (P < 0.05). The cyclin D1 protein level was also positively correlated with that of STAT3 (P < 0.05). However there was no correlation of mRNA levels between cyclin D1 and p42/44MAPK.</p><p><b>CONCLUSION</b>Regulation of the Jak/STAT3 signaling pathway may play an important role in the effect of acitretin on epidermal squamous-cell carcinoma cells. The abnormal expression of STAT3 can be regarded as a prerequisite for acitretin treatment effect.</p>

Acitretin induces apoptosis and changes of relative signaling pathway in epidermoid carcinoma cell line A431 / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To study the effects of Acitretin on growth inhibition and apoptosis of epidermoid carcinoma cell line A431 and its molecular mechanisms.</p><p><b>METHODS</b>A431 cells were treated with Acitretin at the concentration of 10(-5)mol/L in different time intervals. The inhibition of cell growth was determined by MTT method, morphological changes were observed by electron microscopy, apoptosis was assessed by flow cytometry and Annexin-V staining. The mRNA expression levels of STAT3, cyclinD1 and p42/44MAPK were detected by reverse transcriptase polymerase chain reaction (RT-PCR). The protein expression levels of P-STAT3 and CyclinD1 were observed by Western blot in A431 cells.</p><p><b>RESULT</b>(1)Acitretin inhibited the growth of A431 cells in vitro in a dose-and time-dependent manner. Morphological changes revealed characteristics of cell apoptosis. Flow cytometry showed more sub-G(1) phase in A431 cells and more cells positively stained with Annexin-V. (2)Acitretin significantly inhibited the expression of STAT3 and CyclinD1 mRNA in A431 cells in vitro in a time-dependent manner(P<0.05). The p-STAT3 and CyclinD1 protein levels were down regulated. The Acitretin could also down regulate the p42/4MAPK mRNA in A431 cells. (3) After incubation with Acitretin, the mRNA level of CyclinD1 in A431 cells was positively correlated with that of STAT3(p<0.05). The protein level of CyclinD1 was also positively correlated with that of p-STAT3(p<0.05). However, there was no correlation between Mrna levels of CyclinD1 and p42/44MAPK.</p><p><b>CONCLUSION</b>(1)Acitretin plays an inhibitory role in the tumor cell growth and induces the cell apoptosis in A431 cells. (2)The regulation of the Jak/STAT3 signaling pathway may play an important role in inducing growth inhibition and apoptosis by Acitretin in A431 cells.</p>

Skin-like structure generated from implantation of hair follicle bulb cells into collagen/chitosan porous scaffolds in vitro / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To observe the skin regeneration after hair follicle bulb cells were implanted into collagen/chitosan porous scaffolds in vitro.</p><p><b>METHODS</b>The cultured dorsal hair follicle bulb cells of 4d-old C57BL/6J mice were implanted into collagen/chitosan porous scaffolds in vitro. The skin regeneration was observed.</p><p><b>RESULT</b>The skin-like structure was formed on the collagen/chitosan porous scaffolds where were cultured the hair follicle bulb cells before 4th passages.</p><p><b>CONCLUSION</b>The skin-like structure is generated in vitro when early passages of cultured hair bulb cells are implanted into collagen/chitosan porous scaffolds.</p>

Effect of STAT3 phosphorylation and p53 expression on human epidermal non melanoma cutaneous tumors / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To investigate the effect of stat3 phosphorylation and p53 expression on human epidermal non-melanoma cutaneous tumours.</p><p><b>METHODS</b>Immunohistochemistry technique was employed to measure the expression of p-stat3 and p53 protein in skin tissue from 30 cases of skin squamous cell carcinoma (SCC), 20 cases of basal cell carcinoma (BCC), 20 cases of seborrhoeic keratosis (SK) and 20 normal subjects.</p><p><b>RESULT</b>(1) p-stat3 protein was abnormally increased in SCC and BCC as compared with normal skin and SK. Expression of p-stat3 in SCC was also significantly higher than that in BCC. (2) Expression of p-stat3 was higher in poorly-differentiated cancers than that in well-differentiated cancers in SCC. The positive rate of p-stat3 expression was correlated with the depth of tumor invasion, but not with tumor size. (3) There was no p53 protein expression on normal skin and SK, it was significantly upregulated in SCC and BCC. In SCC, the intensity of p53 expression was associated with tumor differentiation. There was no correlation between the positive rate of p53 expression and the depth of tumor invasion, whereas the positive rate of p53 expression was correlated with the sun-exposure area. (4) There existed positive correlation between the expression intensity of p-stat3 and p53 in SCC (r=0.641, P<0.05).</p><p><b>CONCLUSION</b>(1) The overexpression of p-stat3 may play an important role in the development of epidermal tumors. (2) The abnormal activation of stat3 may be related to metastatic potentials in SCC. (3) Both p53 gene and stat3 may contribute to the pathogenesis of skin SCC.</p>