K-sam-related gene, N-sam, encodes fibroblast growth factor receptor and is expressed in T-lymphocytic tumors.
We recently reported the isolation of the K-sam complementary DNA (cDNA), which was amplified preferentially in poorly differentiated types of stomach cancer and codes for one of the heparin-binding growth factor or fibroblast growth factor (FGF) receptor families. The K-sam-related gene, N-sam (NCC-IT-cell-derived sam), was isolated by screening of the cDNA libraries of human immature teratoma cells, NCC-IT. Sequence analysis of the N-sam cDNAs showed that N-sam encodes a human FGF receptor, the FLG protein. N-sam was expressed in lymphocytic leukemia/lymphoma cells, predominantly in the thymic T-cell phenotype. In a T-cell leukemia line, MOLT3, N-sam mRNA expression was markedly enhanced by 12-O-tetradecanoylphorbol-13-acetate treatment and was also up-regulated by basic FGF exposure. These results indicate that N-sam expression is regulated during T-cell ontogeny and modulated by its putative ligand exposure. The results also suggested that interaction between immature T-cell and marrow or thymic interstitial cells might be mediated by N-sam and basic FGF stored in the extracellular matrix of stromal cells.
Hattori
Y
Y
Genetics Division, National Cancer Center Research Institute, Tokyo, Japan.
Odagiri
H
H
Katoh
O
O
Sakamoto
H
H
Morita
T
T
Shimotohno
K
K
Tobinai
K
K
Sugimura
T
T
Terada
M
M
D001483:Base Sequence; D015342:DNA Probes; D004273:DNA, Neoplasm / Q000737:chemistry*; D000091344:Filaggrin Proteins; D015972:Gene Expression Regulation, Neoplastic / Q000235:genetics*; D006801:Humans; D008969:Molecular Sequence Data; D011505:Protein-Tyrosine Kinases / Q000235:genetics*; D012333:RNA, Messenger / Q000032:analysis*; D011956:Receptors, Cell Surface / Q000235:genetics*; D017468:Receptors, Fibroblast Growth Factor; D013601:T-Lymphocytes / Q000737:chemistry; D013724:Teratoma / Q000235:genetics*; D014407:Tumor Cells, Cultured
D015342:DNA Probes; D004273:DNA, Neoplasm; C000717249:FLG protein, human; D000091344:Filaggrin Proteins; D012333:RNA, Messenger; D011956:Receptors, Cell Surface; D017468:Receptors, Fibroblast Growth Factor; D011505:Protein-Tyrosine Kinases