Characterization of TGF-beta-regulated interleukin-8 expression in human prostate cancer cells.
BACKGROUND
Interleukin (IL)-8 and transforming growth factor (TGF)-beta1 are overexpressed in advanced prostate cancer. The purpose of this study was to investigate TGF-beta1-regulated IL-8 expression in prostate cancer cells.


METHODS
TGF-beta receptor expression was evaluated by real-time reverse-transcription PCR (RT-PCR) and Western blotting. TGF-beta1-regulated IL-8 expression was determined by real-time RT-PCR, enzyme-linked immunoabsorbance assay (ELISA), nuclear run-on, and IL-8 promoter reporter assay.


RESULTS
PC-3MM2 cells expressed type I and type II TGF-beta receptors (TbetaRI and TbetaRII). LNCaP cells expressed significantly lower level of TbetaRII. Constitutive expression of IL-8 was detected in PC-3MM2 cells and LNCaP cells engineered with TbetaRII (LNCaP-TbetaRII). TGF-beta1 stimulated IL-8 expression in dose- and time-dependent manners, which was blocked by cycloheximide (CHX) and actinomycin D (ActD). The nuclear run-on and IL-8 luciferase reporter assays show that TGF-beta1 activated IL-8 gene transcription.


CONCLUSIONS
TGF-beta1 signaling regulates IL-8 expression in prostate cancer cells and may contribute to the overexpression of IL-8 in human prostate cancer.
Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, Ohio 45267, USA.
Shan
S
Lu
Zhongyun
Z
Dong
D030201:Activin Receptors, Type I / Q000032:analysis / Q000235:genetics / Q000502:physiology; D015153:Blotting, Western; D045744:Cell Line, Tumor; D003513:Cycloheximide / Q000494:pharmacology; D003609:Dactinomycin / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004797:Enzyme-Linked Immunosorbent Assay; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects* / Q000502:physiology; D006801:Humans; D016209:Interleukin-8 / Q000235:genetics* / Q000502:physiology; D008297:Male; D011471:Prostatic Neoplasms / Q000235:genetics* / Q000473:pathology; D017346:Protein Serine-Threonine Kinases; D012333:RNA, Messenger / Q000032:analysis / Q000235:genetics; D000077293:Receptor, Transforming Growth Factor-beta Type I; D000077294:Receptor, Transforming Growth Factor-beta Type II; D018125:Receptors, Transforming Growth Factor beta / Q000032:analysis / Q000235:genetics / Q000502:physiology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction / Q000502:physiology; D013997:Time Factors; D014158:Transcription, Genetic / Q000187:drug effects; D016212:Transforming Growth Factor beta / Q000235:genetics / Q000502:physiology*; D053773:Transforming Growth Factor beta1
D016209:Interleukin-8; D012333:RNA, Messenger; D018125:Receptors, Transforming Growth Factor beta; C508960:TGFB1 protein, human; D016212:Transforming Growth Factor beta; D053773:Transforming Growth Factor beta1; D003609:Dactinomycin; D003513:Cycloheximide; D017346:Protein Serine-Threonine Kinases; D030201:Activin Receptors, Type I; D000077293:Receptor, Transforming Growth Factor-beta Type I; D000077294:Receptor, Transforming Growth Factor-beta Type II