Analysis of tumor necrosis factor α-induced and nuclear factor κB-silenced LNCaP prostate cancer cells by RT-qPCR.


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Gonen-Korkmaz C., SEVİN G. , GÖKÇE G. , ARUN M. Z. , YILDIRIM G., REEL B. , ...More

Experimental and therapeutic medicine, vol.8, no.6, pp.1695-1700, 2014 (Journal Indexed in SCI Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 8 Issue: 6
  • Publication Date: 2014
  • Doi Number: 10.3892/etm.2014.2032
  • Title of Journal : Experimental and therapeutic medicine
  • Page Numbers: pp.1695-1700
  • Keywords: prostate cancer, cell culture, gene silencing, NF kappa B, TNF alpha, p53, STAMP genes, MOLECULAR-CLONING, SIGNALING PATHWAY, TNF-ALPHA, APOPTOSIS, GENE, INHIBITION, SUPPRESSION, MECHANISMS, SURVIVAL, THERAPY

Abstract

Prostate cancer is the second leading cause of morbidity and mortality in males in the Western world. In the present study, LNCaP, which is an androgen receptor-positive and androgen-responsive prostate cancer cell line derived from lymph node metastasis, and DU 145, which is an androgen receptor-negative prostate cancer cell line derived from brain metastasis, were investigated. TNF alpha treatment decreased p105 and p50 expression and R1881 treatment slightly decreased p105 expression but increased p50 expression with or without TNF alpha induction. As an aggressive prostate cancer cell line, DU145 transfected with six transmembrane protein of prostate (STAMP)1 or STAMP2 was also exposed to TNF alpha. Western blotting indicated that transfection with either STAMP gene caused a significant increase in NF kappa B expression following TNF alpha induction. In addition, following the treatment of LNCaP cells with TNF alpha, reverse transcription quantitative polymerase chain reaction (RT-qPCR) was performed with a panel of apoptosis-related gene primers. The apoptosis-related genes p53, p73, caspase 7 and caspase 9 showed statistically significant increases in expression levels while the expression levels of MDM2 and STAMP1 decreased following TNF alpha induction. Furthermore, LNCaP cells were transfected with a small interfering NF kappa B (siNF kappa B) construct for 1 and 4 days and induced with TNF alpha for the final 24 h. RT-qPCR amplifications were performed with apoptosis-related gene primers, including p53, caspases and STAMPs. However, no changes in the level of STAMP2 were observed between cells in the presence or absence of TNF alpha induction or between those transfected or not transfected with siNF kappa B; however, the level of STAMP1 was significantly decreased by TNF alpha induction, and significantly increased with siNF kappa B transfection. Silencing of the survival gene NF kappa B caused anti-apoptotic STAMPI expression to increase, which repressed p53, together with MDM2. NF kappa B silencing had varying effects on a panel of cancer regulatory genes. Therefore, the effective inhibition of NF kappa B may be critical in providing a targeted pathway for prostate cancer prevention.