Sp1 and Sp3 transcription factors upregulate the proximal promoter of the human prostate-specific antigen gene in prostate cancer cells.
The serum level of prostate-specific antigen (PSA) is useful as a clinical marker for diagnosis and assessment of the progression of prostate cancer, and in evaluating the effectiveness of treatment. We characterized four Sp1/Sp3 binding sites in the proximal promoter of the PSA gene. In a luciferase assay, these sites contributed to the basal promoter activity in prostate cancer cells. In an electrophoretic mobility shift assay and chromatin immunoprecipitation assay, we confirmed that Sp1 and Sp3 bind to these sites. Overexpression of wild-type Sp1 and Sp3 further upregulated the promoter activity, whereas overexpression of the Sp1 dominant-negative form or addition of mithramycin A significantly reduced the promoter activity and the endogenous mRNA level of PSA. Among the four binding sites, a GC box located at nucleotides -53 to -48 was especially critical for basal promoter activity. These results indicate that Sp1 and Sp3 are involved in the basal expression of PSA in prostate cancer cells.
Shin
Toshitaka
T
Department of Anatomy, Biology, and Medicine, Faculty of Medicine, Oita University, 1-1 Idaigaoka, Hasama-machi, Oita 879-5593, Japan. shintosh@med.oita-u.ac.jp
Sumiyoshi
Hideaki
H
Matsuo
Noritaka
N
Satoh
Fuminori
F
Nomura
Yoshio
Y
Mimata
Hiromitsu
H
Yoshioka
Hidekatsu
H
D001665:Binding Sites / Q000235:genetics; D047369:Chromatin Immunoprecipitation; D017931:DNA Primers / Q000235:genetics; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D024202:Electrophoretic Mobility Shift Assay; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects / Q000235:genetics; D017930:Genes, Reporter / Q000235:genetics; D006801:Humans; D008297:Male; D008926:Plicamycin / Q000031:analogs & derivatives* / Q000494:pharmacology; D011401:Promoter Regions, Genetic; D017430:Prostate-Specific Antigen / Q000235:genetics* / Q000378:metabolism; D011471:Prostatic Neoplasms / Q000235:genetics* / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics; D016329:Sp1 Transcription Factor / Q000235:genetics* / Q000378:metabolism; D051705:Sp3 Transcription Factor; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism; D014407:Tumor Cells, Cultured
D017931:DNA Primers; D004268:DNA-Binding Proteins; D012333:RNA, Messenger; C497121:SP3 protein, human; D016329:Sp1 Transcription Factor; D014157:Transcription Factors; D051705:Sp3 Transcription Factor; C066851:mithramycin A; D017430:Prostate-Specific Antigen; D008926:Plicamycin