title: Acidic extracellular microenvironment promotes the invasion and cathepsin B secretion of PC-3 cells.
abstract: BACKGROUND
  This study aimed to investigate the effect of acidic microenvironment on the invasion of prostatic carcinoma PC-3 cells and to explore the potential mechanism.
  
  
  METHODS
  PC-3 cells were maintained in medium at different pHs (pH 7.4, pH 7.0 and pH 6.6). Invasion and metastasis of PC-3 cells were investigated in vitro. Acridine orange staining was performed, followed by laser confocal scanning microscopy for the localization of lysosomes. Western blot assay and ELISA were employed to evaluate the effect of acidic microenvironment on the cathepsin B secretion.
  
  
  RESULTS
  Acidic microenvironment remarkably promote the invasion and migration of PC-3 cells (P<0.01). Moreover, at acidic extracellular pH (pHe), an obvious shift of lysosomes from the perinuclear region to the periphery was observed. Western blot assay and ELISA revealed that acidic microenvironment promoted the cathepsin B secretion in PC- cells.
  
  
  CONCLUSIONS
  Acidic microenvironment may significantly promote the invasion of PC-3 cells and increase the secretion of cathepsin B. This suggests that the acidic microenvironment induced invasion of PC- cells is related to the elevated cathepsin B secretion.
authors.affiliation: Department of Urology, Affiliated Hospital of Guilin Medical College Guilin 541004, Guangxi, China.
authors.forename: Li
authors.initials: L
authors.lastname: Gao
authors.affiliation: Department of Urology, The Third Affiliated Hospital of Sun Yat-Sen University Guangzhou 510630, China.
authors.forename: You-Qiang
authors.initials: YQ
authors.lastname: Fang
authors.affiliation: Department of Urology, Affiliated Hospital of Guilin Medical College Guilin 541004, Guangxi, China.
authors.forename: Tian-Yu
authors.initials: TY
authors.lastname: Zhang
authors.affiliation: Department of Urology, Affiliated Hospital of Guilin Medical College Guilin 541004, Guangxi, China.
authors.forename: Bo
authors.initials: B
authors.lastname: Ge
authors.affiliation: Department of Urology, Affiliated Hospital of Guilin Medical College Guilin 541004, Guangxi, China.
authors.forename: Rong-Jing
authors.initials: RJ
authors.lastname: Tang
authors.affiliation: Department of Urology, Affiliated Hospital of Guilin Medical College Guilin 541004, Guangxi, China.
authors.forename: Jie-Fu
authors.initials: JF
authors.lastname: Huang
authors.affiliation: Department of Urology, Affiliated Hospital of Guilin Medical College Guilin 541004, Guangxi, China.
authors.forename: Lei-Ming
authors.initials: LM
authors.lastname: Jiang
authors.affiliation: Guangxi Key Laboratory of Molecular Medicine in Liver Injury and Repair, Guilin Medical College Guilin 541004, Guangxi, China.
authors.forename: Ning
authors.initials: N
authors.lastname: Tan
keywords: Acidic extracellular microenvironment; cathepsin B; human prostatic cancer; invasion; lysosome