Effects of tacrolimus on the expression of nuclear factor-κB and glucocorticoid receptor by HaCaT cells in vitro

Objective To investigate the effect of tacrolimus on the expression of nuclear factor-κB (NF-κB) in HaCaT cells stimulated by tumor necrosis factor-α(TNF-α),and on the expression of glucocorticoid receptor (GR)α and β in untreated HaCaT cells in vitro.Methods Cultured Ha CaT cells were treated with TNF-α(10μg/L) only,combination of TNF-α(10μg/L) and various concentrations (10-8mol/L, 10-7mol/L,10-6moL/L) of tacrolimus or tacrolimus of different concentrations only.After additional 12-,24-, 36- or 48-hour cnlture, Westem blot and immunofluorescenee-confocal laser scanning microscopy were used to detect the expressions of NF-κB,GRα and GRβ in HaCaT cells.Those untreated HaCaT cells served as the control.Results The relative protein expression level of NF-κB was increased in HaCaT cells after treatment with TNF-α for 24 and 48 hours zompared with untreated ceils (0.73±0.0316 and 0.8925±0.0171 vs 0.4988±0.03506,both P<0.05);however,the increase in NF-κB expression was inhibited by the combination treatment with tacrolimus,and the relative expression level of NF-κB protein was 0.6825±0.0263.0.6200±0.0163 and 0.5575±0.0299 in HaCaT cells treated with TNF-α plus tacrolimus of 10-8mol/L 10-7mol/L and 10-6mol/L,respectively;the difference was significant etween TNF-α-treated cells and those dealt with the combination of NF-α and tacrolimus of 10-7 or 10-6 mol/L (both P<0.05).No significant difference was observed in the expression of NF-κB by HaCaT cells between different time oints treated with tacrolimus of 10-8,10-7 or 10-6 mol/L.Also,there was no zignificant difference in the expression of GRα or GRβ between untreated HaCaT cells and those treated with tacrolimus of 10-8, 10-7 or 10-6 mol/L at any time point.Conclusions Tacrolimus ould inhibit the expression of NF-κB by TNF-α-stimulated HaCaT cells,but does not affect the expression of GRα or GRβ,in untreated HaCaT cells.     

Effects of tacrolimus on the expression of nuclear factor-κB and glucocorticoid receptor by HaCaT cells in vitro

Objective To investigate the effect of tacrolimus on the expression of nuclear factor-κB (NF-κB) in HaCaT cells stimulated by tumor necrosis factor-α(TNF-α),and on the expression of glucocorticoid receptor (GR)α and β in untreated HaCaT cells in vitro.Methods Cultured Ha CaT cells were treated with TNF-α(10μg/L) only,combination of TNF-α(10μg/L) and various concentrations (10-8mol/L, 10-7mol/L,10-6moL/L) of tacrolimus or tacrolimus of different concentrations only.After additional 12-,24-, 36- or 48-hour cnlture, Westem blot and immunofluorescenee-confocal laser scanning microscopy were used to detect the expressions of NF-κB,GRα and GRβ in HaCaT cells.Those untreated HaCaT cells served as the control.Results The relative protein expression level of NF-κB was increased in HaCaT cells after treatment with TNF-α for 24 and 48 hours zompared with untreated ceils (0.73±0.0316 and 0.8925±0.0171 vs 0.4988±0.03506,both P<0.05);however,the increase in NF-κB expression was inhibited by the combination treatment with tacrolimus,and the relative expression level of NF-κB protein was 0.6825±0.0263.0.6200±0.0163 and 0.5575±0.0299 in HaCaT cells treated with TNF-α plus tacrolimus of 10-8mol/L 10-7mol/L and 10-6mol/L,respectively;the difference was significant etween TNF-α-treated cells and those dealt with the combination of NF-α and tacrolimus of 10-7 or 10-6 mol/L (both P<0.05).No significant difference was observed in the expression of NF-κB by HaCaT cells between different time oints treated with tacrolimus of 10-8,10-7 or 10-6 mol/L.Also,there was no zignificant difference in the expression of GRα or GRβ between untreated HaCaT cells and those treated with tacrolimus of 10-8, 10-7 or 10-6 mol/L at any time point.Conclusions Tacrolimus ould inhibit the expression of NF-κB by TNF-α-stimulated HaCaT cells,but does not affect the expression of GRα or GRβ,in untreated HaCaT cells.     

Spa-1和Ki-67在乳房外Paget病肿瘤组织中的表达

目的 探讨Spa-1在乳房外Paget病发生和转移中可能的作用.方法 取17例原位乳房外Paget病和12例侵袭性乳房外Paget病患者皮损及9例正常人皮肤组织,用免疫组化分别检测Spa-1和Ki-67的表达.结果 Spa-1在胞质中显色,Ki-67在胞核中显色.Spa-1和Ki-67仅少量表达于正常人皮肤基底层,在乳房外Paget病肿瘤组织中的表达明显高于正常人皮肤(P<0.01).Spa-1在侵袭性乳房外Paget病肿瘤组织中表达明显高于原位乳房外Paget病(P<0.01).乳房外Paget病肿瘤组织中Spa-1的表达与Ki-67的表达呈正相关.结论 Spa-1在乳房外Paget病的发生发展中可能起作用.

Abstract：

Objective To investigate the potential role of Spa-1 in the development and metastasis of EMPD.Methods Tissue specimens were resected from 17 patients with primary EMPD,12 patients with invasive EMPD and 9 normal human controls.Immunohistochemistry was performed to measure the expression of spa-1 and Ki-67.Results Positive staining was observed for Spa-1 in cytoplasm,and for Ki-67 in cell nuclei.Spa-1 and Ki-67 were weakly expressed in the basal layer of normal skin.The expression of Spa-1 and Ki-67 in EMPD tissue were statistically higher than those in the normal control tissue (both P<0.01).Increased expression of Spa-1 was noted in invasive EMPD tissue compared with in situ EMPD tissue.The expression of Spa-1 was positively correlated with that of Ki-67 in the tissue of EMPD.Conclusion Spa-1 may play a certain role in the initiation and progression of EMPD.     

内皮素对黑素瘤A375细胞转化生长因子-β1及磷酸化Smad 3蛋白表达的调节

Objective To investigate the effects ofendothelin-1 (ET-1) and endothelin-3 (ET-3) on the expression of transformation growth factor-beta 1 (TGF-β1) and phosphorylation of Smad 3 in malignant melanoma cell line, A375. Methods Cultured A375 cells were classified into 5 groups, i.e. control group (no stimulation), ET-1 group (stimulated with ET-1), ET-1+BQ123 group (treated with ET-1 and BQ123),ET-1 + BQ788 group (treated with ET-1 and BQ788), ET-3 group (stimulated with ET-3), to receive different stimulation. The working concentrations were 0, 0.1, 1, 10, 100 nmol/L for ET-1 and ET-3, 10 μmol/L for BQ123 and BQ788. After another 12- and 24-hour culture, ELISA, RT-PCR and Western blot were used to detect the expression of TGF-β1 protein and mRNA as well as phosphorylated Smad 3 (P-Smad 3). Results The expression of TGF-β1 in A375 cells was up-regulated by ET-1, but down-regulated by ET-3, and both of the effects were in a concentration-dependent manner. Under the stimulation with ET-1 and ET-3 of 100 nmol/L, the level of TGF-β1 reached 1289.38 ± 89.42 ng/L per 105 cells and 85.09 ± 9.37 ng/L per 105 cells, respectively, significantly different from that in unstimulated cells (both P < 0.05). BQ123 signifi-cantly blocked the up-regnlatory effect of ET-1 on the expression TGF-β1 protein(P < 0.05), but BQ788 had no significant influence on the effect, so was the case with TGF-β1 mRNA. Western blot revealed that ET-1significantly elevated the expression of P-Smad 3 in A375 cells (P <0.05), and the elevation was significantly inhibited by BQ123, but not by BQ788. The expression of P-Smad 3 was statistically decreased by ET-3 in A375 cells (P <0.05). Conclusions The expression of TGF-β1 could be enhanced by ET-1, but suppressed by ET-3. It is likely that endothelin receptor A mediates the phosphorylation of Smad 3 induced by ET-1.     

内皮素对黑素瘤A375细胞转化生长因子-β1及磷酸化Smad 3蛋白表达的调节

Objective To investigate the effects ofendothelin-1 (ET-1) and endothelin-3 (ET-3) on the expression of transformation growth factor-beta 1 (TGF-β1) and phosphorylation of Smad 3 in malignant melanoma cell line, A375. Methods Cultured A375 cells were classified into 5 groups, i.e. control group (no stimulation), ET-1 group (stimulated with ET-1), ET-1+BQ123 group (treated with ET-1 and BQ123),ET-1 + BQ788 group (treated with ET-1 and BQ788), ET-3 group (stimulated with ET-3), to receive different stimulation. The working concentrations were 0, 0.1, 1, 10, 100 nmol/L for ET-1 and ET-3, 10 μmol/L for BQ123 and BQ788. After another 12- and 24-hour culture, ELISA, RT-PCR and Western blot were used to detect the expression of TGF-β1 protein and mRNA as well as phosphorylated Smad 3 (P-Smad 3). Results The expression of TGF-β1 in A375 cells was up-regulated by ET-1, but down-regulated by ET-3, and both of the effects were in a concentration-dependent manner. Under the stimulation with ET-1 and ET-3 of 100 nmol/L, the level of TGF-β1 reached 1289.38 ± 89.42 ng/L per 105 cells and 85.09 ± 9.37 ng/L per 105 cells, respectively, significantly different from that in unstimulated cells (both P < 0.05). BQ123 signifi-cantly blocked the up-regnlatory effect of ET-1 on the expression TGF-β1 protein(P < 0.05), but BQ788 had no significant influence on the effect, so was the case with TGF-β1 mRNA. Western blot revealed that ET-1significantly elevated the expression of P-Smad 3 in A375 cells (P <0.05), and the elevation was significantly inhibited by BQ123, but not by BQ788. The expression of P-Smad 3 was statistically decreased by ET-3 in A375 cells (P <0.05). Conclusions The expression of TGF-β1 could be enhanced by ET-1, but suppressed by ET-3. It is likely that endothelin receptor A mediates the phosphorylation of Smad 3 induced by ET-1.     

内皮素对黑素瘤A375细胞转化生长因子-β1及磷酸化Smad 3蛋白表达的调节

Objective To investigate the effects ofendothelin-1 (ET-1) and endothelin-3 (ET-3) on the expression of transformation growth factor-beta 1 (TGF-β1) and phosphorylation of Smad 3 in malignant melanoma cell line, A375. Methods Cultured A375 cells were classified into 5 groups, i.e. control group (no stimulation), ET-1 group (stimulated with ET-1), ET-1+BQ123 group (treated with ET-1 and BQ123),ET-1 + BQ788 group (treated with ET-1 and BQ788), ET-3 group (stimulated with ET-3), to receive different stimulation. The working concentrations were 0, 0.1, 1, 10, 100 nmol/L for ET-1 and ET-3, 10 μmol/L for BQ123 and BQ788. After another 12- and 24-hour culture, ELISA, RT-PCR and Western blot were used to detect the expression of TGF-β1 protein and mRNA as well as phosphorylated Smad 3 (P-Smad 3). Results The expression of TGF-β1 in A375 cells was up-regulated by ET-1, but down-regulated by ET-3, and both of the effects were in a concentration-dependent manner. Under the stimulation with ET-1 and ET-3 of 100 nmol/L, the level of TGF-β1 reached 1289.38 ± 89.42 ng/L per 105 cells and 85.09 ± 9.37 ng/L per 105 cells, respectively, significantly different from that in unstimulated cells (both P < 0.05). BQ123 signifi-cantly blocked the up-regnlatory effect of ET-1 on the expression TGF-β1 protein(P < 0.05), but BQ788 had no significant influence on the effect, so was the case with TGF-β1 mRNA. Western blot revealed that ET-1significantly elevated the expression of P-Smad 3 in A375 cells (P <0.05), and the elevation was significantly inhibited by BQ123, but not by BQ788. The expression of P-Smad 3 was statistically decreased by ET-3 in A375 cells (P <0.05). Conclusions The expression of TGF-β1 could be enhanced by ET-1, but suppressed by ET-3. It is likely that endothelin receptor A mediates the phosphorylation of Smad 3 induced by ET-1.     

内皮素对黑素瘤A375细胞转化生长因子-β1及磷酸化Smad 3蛋白表达的调节

Objective To investigate the effects ofendothelin-1 (ET-1) and endothelin-3 (ET-3) on the expression of transformation growth factor-beta 1 (TGF-β1) and phosphorylation of Smad 3 in malignant melanoma cell line, A375. Methods Cultured A375 cells were classified into 5 groups, i.e. control group (no stimulation), ET-1 group (stimulated with ET-1), ET-1+BQ123 group (treated with ET-1 and BQ123),ET-1 + BQ788 group (treated with ET-1 and BQ788), ET-3 group (stimulated with ET-3), to receive different stimulation. The working concentrations were 0, 0.1, 1, 10, 100 nmol/L for ET-1 and ET-3, 10 μmol/L for BQ123 and BQ788. After another 12- and 24-hour culture, ELISA, RT-PCR and Western blot were used to detect the expression of TGF-β1 protein and mRNA as well as phosphorylated Smad 3 (P-Smad 3). Results The expression of TGF-β1 in A375 cells was up-regulated by ET-1, but down-regulated by ET-3, and both of the effects were in a concentration-dependent manner. Under the stimulation with ET-1 and ET-3 of 100 nmol/L, the level of TGF-β1 reached 1289.38 ± 89.42 ng/L per 105 cells and 85.09 ± 9.37 ng/L per 105 cells, respectively, significantly different from that in unstimulated cells (both P < 0.05). BQ123 signifi-cantly blocked the up-regnlatory effect of ET-1 on the expression TGF-β1 protein(P < 0.05), but BQ788 had no significant influence on the effect, so was the case with TGF-β1 mRNA. Western blot revealed that ET-1significantly elevated the expression of P-Smad 3 in A375 cells (P <0.05), and the elevation was significantly inhibited by BQ123, but not by BQ788. The expression of P-Smad 3 was statistically decreased by ET-3 in A375 cells (P <0.05). Conclusions The expression of TGF-β1 could be enhanced by ET-1, but suppressed by ET-3. It is likely that endothelin receptor A mediates the phosphorylation of Smad 3 induced by ET-1.     

内皮素对黑素瘤A375细胞转化生长因子-β1及磷酸化Smad 3蛋白表达的调节

Objective To investigate the effects ofendothelin-1 (ET-1) and endothelin-3 (ET-3) on the expression of transformation growth factor-beta 1 (TGF-β1) and phosphorylation of Smad 3 in malignant melanoma cell line, A375. Methods Cultured A375 cells were classified into 5 groups, i.e. control group (no stimulation), ET-1 group (stimulated with ET-1), ET-1+BQ123 group (treated with ET-1 and BQ123),ET-1 + BQ788 group (treated with ET-1 and BQ788), ET-3 group (stimulated with ET-3), to receive different stimulation. The working concentrations were 0, 0.1, 1, 10, 100 nmol/L for ET-1 and ET-3, 10 μmol/L for BQ123 and BQ788. After another 12- and 24-hour culture, ELISA, RT-PCR and Western blot were used to detect the expression of TGF-β1 protein and mRNA as well as phosphorylated Smad 3 (P-Smad 3). Results The expression of TGF-β1 in A375 cells was up-regulated by ET-1, but down-regulated by ET-3, and both of the effects were in a concentration-dependent manner. Under the stimulation with ET-1 and ET-3 of 100 nmol/L, the level of TGF-β1 reached 1289.38 ± 89.42 ng/L per 105 cells and 85.09 ± 9.37 ng/L per 105 cells, respectively, significantly different from that in unstimulated cells (both P < 0.05). BQ123 signifi-cantly blocked the up-regnlatory effect of ET-1 on the expression TGF-β1 protein(P < 0.05), but BQ788 had no significant influence on the effect, so was the case with TGF-β1 mRNA. Western blot revealed that ET-1significantly elevated the expression of P-Smad 3 in A375 cells (P <0.05), and the elevation was significantly inhibited by BQ123, but not by BQ788. The expression of P-Smad 3 was statistically decreased by ET-3 in A375 cells (P <0.05). Conclusions The expression of TGF-β1 could be enhanced by ET-1, but suppressed by ET-3. It is likely that endothelin receptor A mediates the phosphorylation of Smad 3 induced by ET-1.     

内皮素对黑素瘤A375细胞转化生长因子-β1及磷酸化Smad 3蛋白表达的调节

Objective To investigate the effects ofendothelin-1 (ET-1) and endothelin-3 (ET-3) on the expression of transformation growth factor-beta 1 (TGF-β1) and phosphorylation of Smad 3 in malignant melanoma cell line, A375. Methods Cultured A375 cells were classified into 5 groups, i.e. control group (no stimulation), ET-1 group (stimulated with ET-1), ET-1+BQ123 group (treated with ET-1 and BQ123),ET-1 + BQ788 group (treated with ET-1 and BQ788), ET-3 group (stimulated with ET-3), to receive different stimulation. The working concentrations were 0, 0.1, 1, 10, 100 nmol/L for ET-1 and ET-3, 10 μmol/L for BQ123 and BQ788. After another 12- and 24-hour culture, ELISA, RT-PCR and Western blot were used to detect the expression of TGF-β1 protein and mRNA as well as phosphorylated Smad 3 (P-Smad 3). Results The expression of TGF-β1 in A375 cells was up-regulated by ET-1, but down-regulated by ET-3, and both of the effects were in a concentration-dependent manner. Under the stimulation with ET-1 and ET-3 of 100 nmol/L, the level of TGF-β1 reached 1289.38 ± 89.42 ng/L per 105 cells and 85.09 ± 9.37 ng/L per 105 cells, respectively, significantly different from that in unstimulated cells (both P < 0.05). BQ123 signifi-cantly blocked the up-regnlatory effect of ET-1 on the expression TGF-β1 protein(P < 0.05), but BQ788 had no significant influence on the effect, so was the case with TGF-β1 mRNA. Western blot revealed that ET-1significantly elevated the expression of P-Smad 3 in A375 cells (P <0.05), and the elevation was significantly inhibited by BQ123, but not by BQ788. The expression of P-Smad 3 was statistically decreased by ET-3 in A375 cells (P <0.05). Conclusions The expression of TGF-β1 could be enhanced by ET-1, but suppressed by ET-3. It is likely that endothelin receptor A mediates the phosphorylation of Smad 3 induced by ET-1.     

内皮素对黑素瘤A375细胞转化生长因子-β1及磷酸化Smad 3蛋白表达的调节

Objective To investigate the effects ofendothelin-1 (ET-1) and endothelin-3 (ET-3) on the expression of transformation growth factor-beta 1 (TGF-β1) and phosphorylation of Smad 3 in malignant melanoma cell line, A375. Methods Cultured A375 cells were classified into 5 groups, i.e. control group (no stimulation), ET-1 group (stimulated with ET-1), ET-1+BQ123 group (treated with ET-1 and BQ123),ET-1 + BQ788 group (treated with ET-1 and BQ788), ET-3 group (stimulated with ET-3), to receive different stimulation. The working concentrations were 0, 0.1, 1, 10, 100 nmol/L for ET-1 and ET-3, 10 μmol/L for BQ123 and BQ788. After another 12- and 24-hour culture, ELISA, RT-PCR and Western blot were used to detect the expression of TGF-β1 protein and mRNA as well as phosphorylated Smad 3 (P-Smad 3). Results The expression of TGF-β1 in A375 cells was up-regulated by ET-1, but down-regulated by ET-3, and both of the effects were in a concentration-dependent manner. Under the stimulation with ET-1 and ET-3 of 100 nmol/L, the level of TGF-β1 reached 1289.38 ± 89.42 ng/L per 105 cells and 85.09 ± 9.37 ng/L per 105 cells, respectively, significantly different from that in unstimulated cells (both P < 0.05). BQ123 signifi-cantly blocked the up-regnlatory effect of ET-1 on the expression TGF-β1 protein(P < 0.05), but BQ788 had no significant influence on the effect, so was the case with TGF-β1 mRNA. Western blot revealed that ET-1significantly elevated the expression of P-Smad 3 in A375 cells (P <0.05), and the elevation was significantly inhibited by BQ123, but not by BQ788. The expression of P-Smad 3 was statistically decreased by ET-3 in A375 cells (P <0.05). Conclusions The expression of TGF-β1 could be enhanced by ET-1, but suppressed by ET-3. It is likely that endothelin receptor A mediates the phosphorylation of Smad 3 induced by ET-1.     

内皮素对黑素瘤A375细胞转化生长因子-β1及磷酸化Smad 3蛋白表达的调节

Objective To investigate the effects ofendothelin-1 (ET-1) and endothelin-3 (ET-3) on the expression of transformation growth factor-beta 1 (TGF-β1) and phosphorylation of Smad 3 in malignant melanoma cell line, A375. Methods Cultured A375 cells were classified into 5 groups, i.e. control group (no stimulation), ET-1 group (stimulated with ET-1), ET-1+BQ123 group (treated with ET-1 and BQ123),ET-1 + BQ788 group (treated with ET-1 and BQ788), ET-3 group (stimulated with ET-3), to receive different stimulation. The working concentrations were 0, 0.1, 1, 10, 100 nmol/L for ET-1 and ET-3, 10 μmol/L for BQ123 and BQ788. After another 12- and 24-hour culture, ELISA, RT-PCR and Western blot were used to detect the expression of TGF-β1 protein and mRNA as well as phosphorylated Smad 3 (P-Smad 3). Results The expression of TGF-β1 in A375 cells was up-regulated by ET-1, but down-regulated by ET-3, and both of the effects were in a concentration-dependent manner. Under the stimulation with ET-1 and ET-3 of 100 nmol/L, the level of TGF-β1 reached 1289.38 ± 89.42 ng/L per 105 cells and 85.09 ± 9.37 ng/L per 105 cells, respectively, significantly different from that in unstimulated cells (both P < 0.05). BQ123 signifi-cantly blocked the up-regnlatory effect of ET-1 on the expression TGF-β1 protein(P < 0.05), but BQ788 had no significant influence on the effect, so was the case with TGF-β1 mRNA. Western blot revealed that ET-1significantly elevated the expression of P-Smad 3 in A375 cells (P <0.05), and the elevation was significantly inhibited by BQ123, but not by BQ788. The expression of P-Smad 3 was statistically decreased by ET-3 in A375 cells (P <0.05). Conclusions The expression of TGF-β1 could be enhanced by ET-1, but suppressed by ET-3. It is likely that endothelin receptor A mediates the phosphorylation of Smad 3 induced by ET-1.     

内皮素对黑素瘤A375细胞转化生长因子-β1及磷酸化Smad 3蛋白表达的调节

Objective To investigate the effects ofendothelin-1 (ET-1) and endothelin-3 (ET-3) on the expression of transformation growth factor-beta 1 (TGF-β1) and phosphorylation of Smad 3 in malignant melanoma cell line, A375. Methods Cultured A375 cells were classified into 5 groups, i.e. control group (no stimulation), ET-1 group (stimulated with ET-1), ET-1+BQ123 group (treated with ET-1 and BQ123),ET-1 + BQ788 group (treated with ET-1 and BQ788), ET-3 group (stimulated with ET-3), to receive different stimulation. The working concentrations were 0, 0.1, 1, 10, 100 nmol/L for ET-1 and ET-3, 10 μmol/L for BQ123 and BQ788. After another 12- and 24-hour culture, ELISA, RT-PCR and Western blot were used to detect the expression of TGF-β1 protein and mRNA as well as phosphorylated Smad 3 (P-Smad 3). Results The expression of TGF-β1 in A375 cells was up-regulated by ET-1, but down-regulated by ET-3, and both of the effects were in a concentration-dependent manner. Under the stimulation with ET-1 and ET-3 of 100 nmol/L, the level of TGF-β1 reached 1289.38 ± 89.42 ng/L per 105 cells and 85.09 ± 9.37 ng/L per 105 cells, respectively, significantly different from that in unstimulated cells (both P < 0.05). BQ123 signifi-cantly blocked the up-regnlatory effect of ET-1 on the expression TGF-β1 protein(P < 0.05), but BQ788 had no significant influence on the effect, so was the case with TGF-β1 mRNA. Western blot revealed that ET-1significantly elevated the expression of P-Smad 3 in A375 cells (P <0.05), and the elevation was significantly inhibited by BQ123, but not by BQ788. The expression of P-Smad 3 was statistically decreased by ET-3 in A375 cells (P <0.05). Conclusions The expression of TGF-β1 could be enhanced by ET-1, but suppressed by ET-3. It is likely that endothelin receptor A mediates the phosphorylation of Smad 3 induced by ET-1.     

内皮素对黑素瘤A375细胞转化生长因子-β1及磷酸化Smad 3蛋白表达的调节

Objective To investigate the effects ofendothelin-1 (ET-1) and endothelin-3 (ET-3) on the expression of transformation growth factor-beta 1 (TGF-β1) and phosphorylation of Smad 3 in malignant melanoma cell line, A375. Methods Cultured A375 cells were classified into 5 groups, i.e. control group (no stimulation), ET-1 group (stimulated with ET-1), ET-1+BQ123 group (treated with ET-1 and BQ123),ET-1 + BQ788 group (treated with ET-1 and BQ788), ET-3 group (stimulated with ET-3), to receive different stimulation. The working concentrations were 0, 0.1, 1, 10, 100 nmol/L for ET-1 and ET-3, 10 μmol/L for BQ123 and BQ788. After another 12- and 24-hour culture, ELISA, RT-PCR and Western blot were used to detect the expression of TGF-β1 protein and mRNA as well as phosphorylated Smad 3 (P-Smad 3). Results The expression of TGF-β1 in A375 cells was up-regulated by ET-1, but down-regulated by ET-3, and both of the effects were in a concentration-dependent manner. Under the stimulation with ET-1 and ET-3 of 100 nmol/L, the level of TGF-β1 reached 1289.38 ± 89.42 ng/L per 105 cells and 85.09 ± 9.37 ng/L per 105 cells, respectively, significantly different from that in unstimulated cells (both P < 0.05). BQ123 signifi-cantly blocked the up-regnlatory effect of ET-1 on the expression TGF-β1 protein(P < 0.05), but BQ788 had no significant influence on the effect, so was the case with TGF-β1 mRNA. Western blot revealed that ET-1significantly elevated the expression of P-Smad 3 in A375 cells (P <0.05), and the elevation was significantly inhibited by BQ123, but not by BQ788. The expression of P-Smad 3 was statistically decreased by ET-3 in A375 cells (P <0.05). Conclusions The expression of TGF-β1 could be enhanced by ET-1, but suppressed by ET-3. It is likely that endothelin receptor A mediates the phosphorylation of Smad 3 induced by ET-1.