S A Milligan1, C Nopajaroonsri. 1. Section of Pulmonary Medicine, Medical Service (111P), VA Medical Center, 510 East Stoner Avenue, Shreveport, LA 71101, USA. shawn.milligan@med.va.gov
Abstract
BACKGROUND: Nuclear factor-kappa B (NF-kappa B) nuclear translocation has an important role in preventing apoptotic cell death in some cancers. However, little is known about the role of NF-kB in non-small cell carcinoma. MATERIALS AND METHODS: Human lung adenocarcinoma cells were stimulated with tumor necrosis factor (TNF) alone or TNF with proteasome inhibitors to block NF-kappa B translocation. Cytotoxicity assays, histone-associated DNA-fragmentation ELISA, immunoblots of poly-(ADP ribose)-polymerase (PARP) and electron microscopy were used to evaluate apoptosis. RESULTS: TNF induced I kappa B proteolysis and NF-kappa B nuclear translocation; however, this was blocked by pretreatment with proteasome inhibitors. TNF alone was not cytotoxic, but when NF-kappa B was blocked TNF induced cell death. Specifically, the cytotoxicity was due to apoptosis as noted by increased DNA-fragmentation, degradation of PARP and characteristic morphology. CONCLUSIONS: Proteasome inhibition was an effective method to inhibit NF-kappa B activation in lung adenocarcinoma cells. TNF in conjunction with. NF-kappa B inhibition was a potent stimulus for apoptosis.
BACKGROUND:Nuclear factor-kappa B (NF-kappa B) nuclear translocation has an important role in preventing apoptotic cell death in some cancers. However, little is known about the role of NF-kB in non-small cell carcinoma. MATERIALS AND METHODS:Humanlung adenocarcinoma cells were stimulated with tumor necrosis factor (TNF) alone or TNF with proteasome inhibitors to block NF-kappa B translocation. Cytotoxicity assays, histone-associated DNA-fragmentation ELISA, immunoblots of poly-(ADP ribose)-polymerase (PARP) and electron microscopy were used to evaluate apoptosis. RESULTS:TNF induced I kappa B proteolysis and NF-kappa B nuclear translocation; however, this was blocked by pretreatment with proteasome inhibitors. TNF alone was not cytotoxic, but when NF-kappa B was blocked TNF induced cell death. Specifically, the cytotoxicity was due to apoptosis as noted by increased DNA-fragmentation, degradation of PARP and characteristic morphology. CONCLUSIONS: Proteasome inhibition was an effective method to inhibit NF-kappa B activation in lung adenocarcinoma cells. TNF in conjunction with. NF-kappa B inhibition was a potent stimulus for apoptosis.
Authors: Georgios T Stathopoulos; Zhiwen Zhu; M Brett Everhart; Ioannis Kalomenidis; William E Lawson; Semra Bilaceroglu; Todd E Peterson; Daphne Mitchell; Fiona E Yull; Richard W Light; Timothy S Blackwell Journal: Am J Respir Cell Mol Biol Date: 2005-10-06 Impact factor: 6.914
Authors: Jay W Tichelaar; Yu Zhang; Jean C leRiche; Paul W Biddinger; Stephen Lam; Marshall W Anderson Journal: BMC Cancer Date: 2005-12-06 Impact factor: 4.430