BACKGROUND: Mutations in the p53 tumor suppressor gene (also known as TP53) are common in human lung cancers. The wild-type form of p53 is dominant over the mutant; thus, restoration of wild-type p53 function in lung cancer cells may suppress their growth as tumors. PURPOSE: We investigated the therapeutic efficacy of direct administration of a retroviral wild-type p53 (wt-p53) expression vector (LNp53B) in an orthotopic human lung cancer model in nu/nu mice. METHODS: Proliferation of H226Br cells was determined by cell counting after infection with LNp53B in vitro. Irradiated (350 cGy) female BALB/c nu/nu mice were inoculated intratracheally with 2 x 10(6) H226Br cells (whose p53 gene has a homozygous mutation at codon 254) and treated beginning 3 days later with an intratracheal instillation of LNp53B retroviral supernatant for 3 days. RESULTS: Infection with LNp53B inhibited proliferation of H226Br cells in vitro. Thirty days after tumor cell inoculation, 62%-80% of the control mice showed macroscopic tumors of the right main stem bronchus. LNp53B suppressed H226Br tumor formation in 62%-100% of mice, and the effect was abrogated by dilution of the retroviral supernatant with inactive vector. CONCLUSIONS: Direct administration of a retroviral vector expressing wt-p53 may inhibit local growth in vivo of human lung cancer cells with abnormal p53 expression. IMPLICATIONS: Development of gene-replacement treatment strategies based on the type of mutations found in target cancers is warranted and may lead to the development of new adjunctive therapies and gene-specific prevention strategies for lung cancer.
BACKGROUND: Mutations in the p53tumor suppressor gene (also known as TP53) are common in human lung cancers. The wild-type form of p53 is dominant over the mutant; thus, restoration of wild-type p53 function in lung cancer cells may suppress their growth as tumors. PURPOSE: We investigated the therapeutic efficacy of direct administration of a retroviral wild-type p53 (wt-p53) expression vector (LNp53B) in an orthotopic humanlung cancer model in nu/nu mice. METHODS: Proliferation of H226Br cells was determined by cell counting after infection with LNp53B in vitro. Irradiated (350 cGy) female BALB/c nu/nu mice were inoculated intratracheally with 2 x 10(6) H226Br cells (whose p53 gene has a homozygous mutation at codon 254) and treated beginning 3 days later with an intratracheal instillation of LNp53B retroviral supernatant for 3 days. RESULTS: Infection with LNp53B inhibited proliferation of H226Br cells in vitro. Thirty days after tumor cell inoculation, 62%-80% of the control mice showed macroscopic tumors of the right main stem bronchus. LNp53B suppressed H226Br tumor formation in 62%-100% of mice, and the effect was abrogated by dilution of the retroviral supernatant with inactive vector. CONCLUSIONS: Direct administration of a retroviral vector expressing wt-p53 may inhibit local growth in vivo of humanlung cancer cells with abnormal p53 expression. IMPLICATIONS: Development of gene-replacement treatment strategies based on the type of mutations found in target cancers is warranted and may lead to the development of new adjunctive therapies and gene-specific prevention strategies for lung cancer.
Authors: Xiquan Cui; Lap Man Lee; Xin Heng; Weiwei Zhong; Paul W Sternberg; Demetri Psaltis; Changhuei Yang Journal: Proc Natl Acad Sci U S A Date: 2008-07-28 Impact factor: 11.205
Authors: M Pariat; S Carillo; M Molinari; C Salvat; L Debüssche; L Bracco; J Milner; M Piechaczyk Journal: Mol Cell Biol Date: 1997-05 Impact factor: 4.272