PURPOSE: Nuclear factor kappaB (NF-kappaB) is an important transcription factor in various biological processes. Constitutive NF-kappaB activation has been noted in many tumors, including colorectal cancers. However, the precise role of this activation in colorectal cancer is unclear. EXPERIMENTAL DESIGN: Constitutive NF-kappaB activation was evaluated in colorectal cancer tissues and cell lines. To inhibit NF-kappaB activation, we established cancer cells with stable knockdown of IkappaB kinase gamma (NF-kappaB essential modulator), which is the regulatory subunit of the IkappaB kinase complex, by RNA interference. Cell growth and apoptosis were evaluated in wild-type cells (WT) and knocked-down cells (KD). Microarray and protein array analysis were also done. To determine involvement of angiogenesis, human umbilical vein endothelial cells were used. By s.c. transplantation of the cells into nude mice, tumor sizes, vascularity, and chemodrug sensitivity were analyzed. RESULTS: Constitutive NF-kappaB activation was observed in 40% of colorectal cancer tissues and 67% of cell lines. Cell proliferation was not different between WT and KD in vitro, whereas apoptosis mediated by tumor necrosis factor-alpha and 5-fluorouracil were increased in KD. Several angiogenic chemokines were decreased in KD. Human umbilical vein endothelial cells incubated in WT supernatant showed more branch points than in KD, suggesting that constitutive NF-kappaB activation was involved in angiogenesis. Subcutaneous tumor expansion was suppressed to 23% in KD, and vessels were also decreased. By 5-fluoruracil treatment, tumor expansion was suppressed to a greater extent in KD (to 6%) than in WT (to 50%). CONCLUSION: NF-kappaB inhibition may represent a potent treatment modality in colorectal cancer, especially in cases with constitutive NF-kappaB activation.
PURPOSE: Nuclear factor kappaB (NF-kappaB) is an important transcription factor in various biological processes. Constitutive NF-kappaB activation has been noted in many tumors, including colorectal cancers. However, the precise role of this activation in colorectal cancer is unclear. EXPERIMENTAL DESIGN: Constitutive NF-kappaB activation was evaluated in colorectal cancer tissues and cell lines. To inhibit NF-kappaB activation, we established cancer cells with stable knockdown of IkappaB kinase gamma (NF-kappaB essential modulator), which is the regulatory subunit of the IkappaB kinase complex, by RNA interference. Cell growth and apoptosis were evaluated in wild-type cells (WT) and knocked-down cells (KD). Microarray and protein array analysis were also done. To determine involvement of angiogenesis, human umbilical vein endothelial cells were used. By s.c. transplantation of the cells into nude mice, tumor sizes, vascularity, and chemodrug sensitivity were analyzed. RESULTS: Constitutive NF-kappaB activation was observed in 40% of colorectal cancer tissues and 67% of cell lines. Cell proliferation was not different between WT and KD in vitro, whereas apoptosis mediated by tumor necrosis factor-alpha and 5-fluorouracil were increased in KD. Several angiogenic chemokines were decreased in KD. Human umbilical vein endothelial cells incubated in WT supernatant showed more branch points than in KD, suggesting that constitutive NF-kappaB activation was involved in angiogenesis. Subcutaneous tumor expansion was suppressed to 23% in KD, and vessels were also decreased. By 5-fluoruracil treatment, tumor expansion was suppressed to a greater extent in KD (to 6%) than in WT (to 50%). CONCLUSION:NF-kappaB inhibition may represent a potent treatment modality in colorectal cancer, especially in cases with constitutive NF-kappaB activation.
Authors: Shing Cheng Tan; Mohd Shafi'i Mohd Suzairi; Abdul Aziz Ahmad Aizat; Mustapha Mohd Aminudin; Mohd Shahpudin Siti Nurfatimah; Venkata Murali Krishna Bhavaraju; Biswa Mohan Biswal; Ravindran Ankathil Journal: Med Oncol Date: 2013-08-31 Impact factor: 3.064
Authors: Ravikumar Muthuswamy; Erik Berk; Beth Fallert Junecko; Herbert J Zeh; Amer H Zureikat; Daniel Normolle; The Minh Luong; Todd A Reinhart; David L Bartlett; Pawel Kalinski Journal: Cancer Res Date: 2012-05-16 Impact factor: 12.701
Authors: Simon C Weli; Trine Fink; Cihan Cetinkaya; Mayuri S Prasad; Cristian P Pennisi; Vladimir Zachar Journal: Int J Stem Cells Date: 2010-05 Impact factor: 2.500