Aim:To determine the effect of saposin C (a known trophic domain of prosaposin) on proliferation,migration and invasion,as well as its effect on the expression of urokinase plasmonogen activator (uPA),its receptor (uP...Aim:To determine the effect of saposin C (a known trophic domain of prosaposin) on proliferation,migration and invasion,as well as its effect on the expression of urokinase plasmonogen activator (uPA),its receptor (uPAR) and matrix metalloproteinases (MMP)-2 and -9 in normal and malignant prostate cells.In addition,we tested whether saposin C can activate p42/44 and stress-activated protein kinase/c-Jun NH_2-terminal kinase (SAPK/JNK) signal transduction pathways of the mitogen-activated protein kinase (MAPK) superfamily.Methods:We employed West- ern blot analysis,phospho-specific antibodies,cell proliferation assay,reverse transcriptase-polymerase chain reaction, in vitro kinase assays and migration and invasion to determine the effect of saposin C on various biological behaviors of prostate stromal and cancer cells.Results:Saposin C,in a cell type-specific manner,upregulates uPA/uPAR and immediate early gene c-Jun expression,stimulates cell proliferation,migration and invasion and activates p42/44 and SAPK/JNK MAPK pathways in prostate stromal and cancer cells.Normal prostate epithelial cells were not responsive to saposin C treatment in the above studies.Conclusion:Saposin C functions as a multipotential modulator of diverse biological activities in prostate cancer and stromal cells.These results strongly suggest that saposin C functions as a potent growth factor for prostatic cells and may contribute to prostate carcinogenesis and/or the development of hormone-refractory prostate cancer.展开更多
Aim: To determine the effects of the functional domain of saposin C (neurotrophic peptide [NP]) on androgen receptor (AR) expression and transcriptional activity. Methods: We constructed DNA vectors expressing N...Aim: To determine the effects of the functional domain of saposin C (neurotrophic peptide [NP]) on androgen receptor (AR) expression and transcriptional activity. Methods: We constructed DNA vectors expressing NP or a chimeric peptide of the viral TAT transduction domain and NP (TAT-NP) using gene cloning technology. The effects of ectopic expression of NP or TAT-NP on cell growth were examined by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl-2H-tetrazolium bromide (MTT) assay. Reverse transcription-polymerase chain reaction (RT-PCR), Western blot, transient transfection and reporter gene assays were used to determine the effects of NP on AR expression and activation. Results: NP stimulated proliferation of androgen responsive LNCaP cells in the absence of androgens. RT-PCR and Western blot analyses showed that ectopic expression of NP resulted in induction of AR gene expression, and that the NP-stimulated expression of AR could be synergistically enhanced in the presence of androgens. Furthermore, reporter gene assay results showed that NP could enhance AR transactivation by increasing androgen-inducible gene reporter activity. Conclusion: We provided evidence that ectopic expression of saposin C-originated NP could upregulate AR gene expression and activate the AR transcriptional function in an androgen-independent manner in prostate cancer cells.展开更多
文摘Aim:To determine the effect of saposin C (a known trophic domain of prosaposin) on proliferation,migration and invasion,as well as its effect on the expression of urokinase plasmonogen activator (uPA),its receptor (uPAR) and matrix metalloproteinases (MMP)-2 and -9 in normal and malignant prostate cells.In addition,we tested whether saposin C can activate p42/44 and stress-activated protein kinase/c-Jun NH_2-terminal kinase (SAPK/JNK) signal transduction pathways of the mitogen-activated protein kinase (MAPK) superfamily.Methods:We employed West- ern blot analysis,phospho-specific antibodies,cell proliferation assay,reverse transcriptase-polymerase chain reaction, in vitro kinase assays and migration and invasion to determine the effect of saposin C on various biological behaviors of prostate stromal and cancer cells.Results:Saposin C,in a cell type-specific manner,upregulates uPA/uPAR and immediate early gene c-Jun expression,stimulates cell proliferation,migration and invasion and activates p42/44 and SAPK/JNK MAPK pathways in prostate stromal and cancer cells.Normal prostate epithelial cells were not responsive to saposin C treatment in the above studies.Conclusion:Saposin C functions as a multipotential modulator of diverse biological activities in prostate cancer and stromal cells.These results strongly suggest that saposin C functions as a potent growth factor for prostatic cells and may contribute to prostate carcinogenesis and/or the development of hormone-refractory prostate cancer.
文摘Aim: To determine the effects of the functional domain of saposin C (neurotrophic peptide [NP]) on androgen receptor (AR) expression and transcriptional activity. Methods: We constructed DNA vectors expressing NP or a chimeric peptide of the viral TAT transduction domain and NP (TAT-NP) using gene cloning technology. The effects of ectopic expression of NP or TAT-NP on cell growth were examined by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl-2H-tetrazolium bromide (MTT) assay. Reverse transcription-polymerase chain reaction (RT-PCR), Western blot, transient transfection and reporter gene assays were used to determine the effects of NP on AR expression and activation. Results: NP stimulated proliferation of androgen responsive LNCaP cells in the absence of androgens. RT-PCR and Western blot analyses showed that ectopic expression of NP resulted in induction of AR gene expression, and that the NP-stimulated expression of AR could be synergistically enhanced in the presence of androgens. Furthermore, reporter gene assay results showed that NP could enhance AR transactivation by increasing androgen-inducible gene reporter activity. Conclusion: We provided evidence that ectopic expression of saposin C-originated NP could upregulate AR gene expression and activate the AR transcriptional function in an androgen-independent manner in prostate cancer cells.
基金Supported by National Natural Science Foundation of China(No.31101266)Scientific Research Program Funded by Education Department of Shaanxi Province(No.12JK0711)~~