title: Pathway specific gene expression profiling reveals oxidative stress genes potentially regulated by transcription co-activator LEDGF/p75 in prostate cancer cells.
abstract: BACKGROUND
  Lens epithelium-derived growth factor p75 (LEDGF/p75) is a stress survival transcription co-activator and autoantigen that is overexpressed in tumors, including prostate cancer (PCa). This oncoprotein promotes resistance to cell death induced by oxidative stress and chemotherapy by mechanisms that remain unclear. To get insights into these mechanisms we identified candidate target stress genes of LEDGF/p75 using pathway-specific gene expression profiling in PCa cells.
  
  
  METHODS
  A "Human oxidative stress and antioxidant defense" qPCR array was used to identify genes exhibiting significant expression changes in response to knockdown or overexpression of LEDGF/p75 in PC-3 cells. Validation of array results was performed by additional qPCR and immunoblotting.
  
  
  RESULTS
  Cytoglobin (CYGB), Phosphoinositide-binding protein PIP3-E/IPCEF-1, superoxidase dismutase 3 (SOD3), thyroid peroxidase (TPO), and albumin (ALB) exhibited significant transcript down- and up-regulation in response to LEDGF/p75 knockdown and overexpression, respectively. CYGB gene was selected for further validation based on its emerging role as a stress oncoprotein in human malignancies. In light of previous reports indicating that LEDGF/p75 regulates peroxiredoxin 6 (PRDX6), and that PRDXs exhibit differential expression in PCa, we also examined the relationship between these proteins in PCa cells. Our validation data revealed that changes in LEDGF/p75 transcript and protein expression in PCa cells closely paralleled those of CYGB, but not those of the PRDXs.
  
  
  CONCLUSIONS
  Our study identifies CYGB and other genes as stress genes potentially regulated by LEDGF/p75 in PCa cells, and provides a rationale for investigating their role in PCa and in promoting resistance to chemotherapy- and oxidative stress-induced cell death.
authors.affiliation: Center for Health Disparities and Molecular Medicine, Department of Basic Sciences, Loma Linda University School of Medicine, Loma Linda, California 92350, USA.
authors.forename: Anamika
authors.initials: A
authors.lastname: Basu
authors.forename: Awa
authors.initials: A
authors.lastname: Drame
authors.forename: Ruben
authors.initials: R
authors.lastname: Muñoz
authors.forename: Rik
authors.initials: R
authors.lastname: Gijsbers
authors.forename: Zeger
authors.initials: Z
authors.lastname: Debyser
authors.forename: Marino
authors.initials: M
authors.lastname: De Leon
authors.forename: Carlos A
authors.initials: CA
authors.lastname: Casiano
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000235:genetics* / Q000378:metabolism; D045744:Cell Line, Tumor; D000078842:Cytoglobin; D020869:Gene Expression Profiling; D005914:Globins / Q000235:genetics / Q000378:metabolism; D006801:Humans; D008297:Male; D046228:Microarray Analysis; D018384:Oxidative Stress / Q000235:genetics*; D011467:Prostate / Q000378:metabolism* / Q000473:pathology; D011471:Prostatic Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D015398:Signal Transduction / Q000235:genetics*; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism; D015533:Transcriptional Activation
chemical_list: D048868:Adaptor Proteins, Signal Transducing; C000627265:CYGB protein, human; D000078842:Cytoglobin; C504649:PSIP1 protein, human; D014157:Transcription Factors; D005914:Globins