Down-regulation of lysyl oxidase-induced tumorigenic transformation in NRK-49F cells characterized by constitutive activation of ras proto-oncogene.

@article{citeulike:1603808, abstract = {Several investigations have suggested a putative tumor suppressor role for lysyl oxidase because it is down-regulated in many human and oncogene-induced tumors. To address this issue we down-regulated the enzyme in normal rat kidney fibroblasts by stable transfection of its cDNA in an antisense orientation. The selected clones revealed an absence of lysyl oxidase and dramatic phenotypic changes, interpretable as signs of transformation. The antisense lysyl oxidase clones showed, indeed, loose attachment to the plate and anchorage-independent growth and were highly tumorigenic in nude mice. Moreover, we found an impaired response of the PDGF and IGF-1 receptors to their ligands. In particular, the transformed cells showed a down-regulation of both PDGF receptors and expressed the 105-kDa isoform of the IGF-1 beta receptor, which was not present in the normal control cells. The lack of response to PDGF-BB has been described as a feature of many ras-transformed phenotypes. Therefore, we looked at the status of the p21(ras). Indeed, we found a significantly higher level of active p21(ras) both during steady-state growth and prolonged starvation. Our data reveal new evidence for a tumor suppressor activity of lysyl oxidase, highlighting its particular role in controlling Ras activation and growth factor dependence.}, address = {Department of Nephrology, Istituto G. Gaslini, Largo G. Gaslini, 5, 16147 Genova, Italy.}, author = {Giampuzzi, M. and Botti, G. and Cilli, M. and Gusmano, R. and Borel, A. and Sommer, P. and Di Donato, A. }, citeulike-article-id = {1603808}, doi = {10.1074/jbc.M101695200}, issn = {0021-9258}, journal = {J Biol Chem}, month = {August}, number = {31}, pages = {29226--29232}, posted-at = {2007-08-29 08:01:19}, priority = {2}, title = {Down-regulation of lysyl oxidase-induced tumorigenic transformation in NRK-49F cells characterized by constitutive activation of ras proto-oncogene.}, url = {http://dx.doi.org/10.1074/jbc.M101695200}, volume = {276}, year = {2001} }

TY - JOUR ID - citeulike:1603808 L3 - citeulike-article-id:1603808 TI - Down-regulation of lysyl oxidase-induced tumorigenic transformation in NRK-49F cells characterized by constitutive activation of ras proto-oncogene. JF - J Biol Chem VL - 276 IS - 31 SP - 29226 EP - 29232 AD - Department of Nephrology, Istituto G. Gaslini, Largo G. Gaslini, 5, 16147 Genova, Italy. SN - 0021-9258 N2 - Several investigations have suggested a putative tumor suppressor role for lysyl oxidase because it is down-regulated in many human and oncogene-induced tumors. To address this issue we down-regulated the enzyme in normal rat kidney fibroblasts by stable transfection of its cDNA in an antisense orientation. The selected clones revealed an absence of lysyl oxidase and dramatic phenotypic changes, interpretable as signs of transformation. The antisense lysyl oxidase clones showed, indeed, loose attachment to the plate and anchorage-independent growth and were highly tumorigenic in nude mice. Moreover, we found an impaired response of the PDGF and IGF-1 receptors to their ligands. In particular, the transformed cells showed a down-regulation of both PDGF receptors and expressed the 105-kDa isoform of the IGF-1 beta receptor, which was not present in the normal control cells. The lack of response to PDGF-BB has been described as a feature of many ras-transformed phenotypes. Therefore, we looked at the status of the p21(ras). Indeed, we found a significantly higher level of active p21(ras) both during steady-state growth and prolonged starvation. Our data reveal new evidence for a tumor suppressor activity of lysyl oxidase, highlighting its particular role in controlling Ras activation and growth factor dependence. AU - Giampuzzi, M AU - Botti, G AU - Cilli, M AU - Gusmano, R AU - Borel, A AU - Sommer, P AU - Di Donato, A PY - 2001/08/03/ UR - http://dx.doi.org/10.1074/jbc.M101695200 ER -