title: Knockdown of PKR expression by RNAi reduces pulmonary metastatic potential of B16-F10 melanoma cells in mice: possible role of NF-kappaB.
abstract: It was suggested that PKR may act as a tumor suppressor. However, the results are still controversial. Here, we investigate the effect of PKR-specific short hairpin RNA (shRNA) expressing plasmids on pulmonary metastatic potential of B16-F10 melanoma cells in mice. Levels of both PKR mRNA and PKR protein were only significantly reduced in tumor cells transfected with plasmid-based PKR-specific shRNA. Injection of tumor cells transfected with PKR-specific shRNA expressing plasmid resulted in inhibition (85%) of metastatic nodules compared with control. Our results suggest that this effect is mediated by the transcription factor NF-kappaB. This study does not support the concept of PKR as a tumor suppressor.
authors.affiliation: Department of Biochemistry and Immunology, School of Medicine University of São Paulo, 14049-900, Ribeirão Preto, SP, Brazil.
authors.forename: Nayara
authors.initials: N
authors.lastname: Delgado André
authors.forename: Fernando L
authors.initials: FL
authors.lastname: De Lucca
mesh_terms: D000818:Animals; D015153:Blotting, Western; D008175:Lung Neoplasms / Q000378:metabolism / Q000517:prevention & control* / Q000556:secondary*; D008297:Male; D008546:Melanoma, Experimental / Q000378:metabolism / Q000473:pathology / Q000628:therapy*; D051379:Mice; D008810:Mice, Inbred C57BL; D016328:NF-kappa B / Q000378:metabolism*; D034741:RNA, Small Interfering / Q000494:pharmacology*; D019892:eIF-2 Kinase / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism
chemical_list: D016328:NF-kappa B; D034741:RNA, Small Interfering; D019892:eIF-2 Kinase