Inflammation-mediated abrogation of androgen signaling: an in vitro model of prostate cell inflammation.
As a link between inflammation and cancer has been reported in many studies, we established an in vitro model of prostatic inflammation to investigate the loss of androgen receptor (AR)-mediated signaling in androgen responsive prostate cell lines. First, the U937 monocyte cell line was differentiated into macrophages using phorbol acetate (PMA), and cells were induced with lipopolysaccharide (LPS) for cytokine secretion. Next, the cytokine levels (TNFα, IL-6, and IL1β) in conditioned media (CM) were analyzed. Prostate cells were then fed with CM containing varying concentrations of TNFα, and IkB degradation, nuclear factor kappa B (NFκB) translocation and transactivation, and the expression of matrix metalloproteinase-8 (MMP8) and matrix metalloproteinase-9 (MMP9) were then assessed. As a result of CM treatment, ubiquitin-mediated AR degradation, which was restored using anti-TNFα antibody neutralization, led to both a decrease in KLK4, PSA, and NKX3.1 expression levels and the upregulation of GPX2. In addition to the loss of AR, acute and chronic CM exposure resulted in p53 degradation and consequent p21 downregulation, which was also restored by either androgen administration or ectopic NKX3.1 expression via the stabilization of MDM2 levels in LNCaP cells. Additionally, CM treatment enhanced H2AX((S139)) phosphorylation (a hallmark of DNA damage) and genetic heterogeneity in the absence of androgens in prostate cells without activating mitochondrial apoptosis. Thus, the data suggest that inflammatory cytokine exposure results in the loss of AR and p53 signaling in prostate cells and facilitates genetic heterogeneity via ROS accumulation to promote prostate carcinogenesis.
Department of Pharmaceutical Biotechnology, Ege University, Bornova, Izmir, Turkey.
Bilge
B
Debelec-Butuner
Cansu
C
Alapinar
Lokman
L
Varisli
Burcu
B
Erbaykent-Tepedelen
Syed Muhammad
SM
Hamid
Ceren
C
Gonen-Korkmaz
Kemal Sami
KS
Korkmaz
D000111:Acetylcysteine / Q000031:analogs & derivatives / Q000494:pharmacology; D000728:Androgens / Q000235:genetics / Q000378:metabolism*; D000975:Antioxidants / Q000378:metabolism / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects / Q000235:genetics; D002454:Cell Differentiation / Q000187:drug effects / Q000235:genetics; D045744:Cell Line, Tumor; D015536:Down-Regulation / Q000187:drug effects / Q000235:genetics; D005979:Glutathione Peroxidase / Q000235:genetics / Q000378:metabolism; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism; D006801:Humans; D020672:I-kappa B Proteins / Q000235:genetics / Q000378:metabolism; D007249:Inflammation / Q000235:genetics / Q000378:metabolism*; D018836:Inflammation Mediators / Q000378:metabolism; D053583:Interleukin-1beta / Q000235:genetics / Q000378:metabolism; D015850:Interleukin-6 / Q000235:genetics / Q000378:metabolism; D007610:Kallikreins / Q000235:genetics / Q000378:metabolism; D008239:Lysine / Q000031:analogs & derivatives / Q000494:pharmacology; D008264:Macrophages / Q000187:drug effects / Q000378:metabolism; D008297:Male; D020780:Matrix Metalloproteinase 9 / Q000235:genetics / Q000378:metabolism; D016328:NF-kappa B / Q000235:genetics / Q000378:metabolism; D010766:Phosphorylation / Q000187:drug effects / Q000235:genetics; D017430:Prostate-Specific Antigen / Q000235:genetics / Q000378:metabolism; D011471:Prostatic Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D011472:Prostatitis / Q000188:drug therapy / Q000378:metabolism* / Q000473:pathology; D051736:Proto-Oncogene Proteins c-mdm2 / Q000235:genetics / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism; D011944:Receptors, Androgen / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism; D015533:Transcriptional Activation / Q000187:drug effects; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics / Q000378:metabolism; D016159:Tumor Suppressor Protein p53 / Q000235:genetics / Q000378:metabolism; D020298:U937 Cells; D015854:Up-Regulation / Q000187:drug effects
C410798:AR protein, human; D000728:Androgens; D000975:Antioxidants; D018398:Homeodomain Proteins; D020672:I-kappa B Proteins; D018836:Inflammation Mediators; D053583:Interleukin-1beta; D015850:Interleukin-6; C086501:N-acetylcysteine lysinate; D016328:NF-kappa B; C491178:NKX3-1 protein, human; D017382:Reactive Oxygen Species; D011944:Receptors, Androgen; C495901:TP53 protein, human; D014157:Transcription Factors; D014409:Tumor Necrosis Factor-alpha; D016159:Tumor Suppressor Protein p53; C117436:GPX2 protein, human; D005979:Glutathione Peroxidase; C497206:MDM2 protein, human; D051736:Proto-Oncogene Proteins c-mdm2; D007610:Kallikreins; C120801:kallikrein 4; D017430:Prostate-Specific Antigen; D020780:Matrix Metalloproteinase 9; D008239:Lysine; D000111:Acetylcysteine