TY - JOUR
T1 - Identification of the product of two oncogenic rearranged forms of the RET proto-oncogene in papillary thyroid carcinomas
AU - Lanzi, C.
AU - Borrello, M. G.
AU - Bongarzone, I.
AU - Migliazza, A.
AU - Fusco, A.
AU - Grieco, M.
AU - Santoro, M.
AU - Gambetta, R. A.
AU - Zunino, F.
AU - Della Porta, G.
AU - Pierotti, M. A.
PY - 1992/11
Y1 - 1992/11
N2 - In papillary thyroid carcinomas, we have identified two tumor-specific rearrangements of the RET proto-oncogene leading to the formation of different transforming fusion products sharing the tyrosine kinase (tk) domain of the proto-oncogene and designated ptc-1 and ptc-2. We have analysed ptc-l and ptc-2 products by immunoprecipitation with specific anti-RET antibodies followed by immunoblotting with the same reagent or with antibodies specific for phosphotyrosine (P-tyr) residues. The anti-RET antibodies were reactive with 64-kDa (p64ptc-1) and 81-kDa (p81ptc-2) proteins from lysates of ptc-1 and ptc-2 transformed cells, respectively, and identified two proteins of 140 kDa and 160 kDa from extracts of SK-N-SH, a neuroblastoma cell line previously shown to express two differently glycosylated forms of the normal RE T product. The anti P-tyr antibodies, while detecting the same p64ptc-1 and p81ptc-2 proteins from ptc-1 and ptc-2 extracts, did not show any specific band in the neuroblastoma lysates. An additional set of experiments led us to conclude that, whereas the normal product of the RET proto-oncogene is a membrane-associated receptor-like molecule not intrinsically phosphorylated on tyrosine, both oncogenic forms of RET, ptc-1 and ptc-2, are constitutively phosphorylated on tyrosine, display an 'in vitro' autophosphorylation activity, are translocated from the membrane to the cytoplasm and are apparently unaffected by protein kinase C modulation.
AB - In papillary thyroid carcinomas, we have identified two tumor-specific rearrangements of the RET proto-oncogene leading to the formation of different transforming fusion products sharing the tyrosine kinase (tk) domain of the proto-oncogene and designated ptc-1 and ptc-2. We have analysed ptc-l and ptc-2 products by immunoprecipitation with specific anti-RET antibodies followed by immunoblotting with the same reagent or with antibodies specific for phosphotyrosine (P-tyr) residues. The anti-RET antibodies were reactive with 64-kDa (p64ptc-1) and 81-kDa (p81ptc-2) proteins from lysates of ptc-1 and ptc-2 transformed cells, respectively, and identified two proteins of 140 kDa and 160 kDa from extracts of SK-N-SH, a neuroblastoma cell line previously shown to express two differently glycosylated forms of the normal RE T product. The anti P-tyr antibodies, while detecting the same p64ptc-1 and p81ptc-2 proteins from ptc-1 and ptc-2 extracts, did not show any specific band in the neuroblastoma lysates. An additional set of experiments led us to conclude that, whereas the normal product of the RET proto-oncogene is a membrane-associated receptor-like molecule not intrinsically phosphorylated on tyrosine, both oncogenic forms of RET, ptc-1 and ptc-2, are constitutively phosphorylated on tyrosine, display an 'in vitro' autophosphorylation activity, are translocated from the membrane to the cytoplasm and are apparently unaffected by protein kinase C modulation.
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M3 - Article
C2 - 1437145
AN - SCOPUS:0026476684
VL - 7
SP - 2189
EP - 2194
JO - Oncogene
JF - Oncogene
SN - 0950-9232
IS - 11
ER -