RRC ID 39346
著者 Sasaki Y, Takahashi T, Miyazaki H, Matsumoto A, Kato T, Nakamura K, Iho S, Okuno Y, Nakao K.
タイトル Production of thrombopoietin by human carcinomas and its novel isoforms.
ジャーナル Blood
Abstract Thrombocytosis is occasionally seen in patients with carcinomas and has been assumed to be attributable to interleukin-6 or granulocyte-macrophage colony-stimulating factor produced by carcinoma cells. In this study, we clarified whether thrombopoietin (TPO) is involved in carcinoma-associated thrombocytosis. Expression of TPO mRNA was observed in the majority of 27 carcinoma cell lines as determined by reverse transcriptase-polymerase chain reaction (RT-PCR). There were 6 PCR products differing in size; sequence analysis showed the full-length TPO mRNA (TPO-1), 12- and 116-bp deleted variants (TPO-2 and TPO-3, respectively), and 3 novel isoforms (197- and 128-bp deleted forms and a 60-bp insert form of TPO-3; named TPO-4, TPO-5, and TPO-6, respectively). Of 27 lines, 24 expressed TPO-1 mRNA with various other isoforms. Culture supernatants of COS-1 cells transfected with TPO-5 or TPO-6 cDNA did not promote the proliferation of TPO-responsive cells, whereas Western blot analysis on the cell lysates demonstrated TPO-5 but not TPO-6 protein, suggesting poor extracellular secretion (TPO-5) or poor protein synthesis (TPO-6). TPO protein was detected in 10-fold concentrated culture supernatants of cells of these carcinoma lines, with a median concentration of 0.38 fmol/mL as evaluated by enzyme-linked immunosorbent assay. High blood TPO levels were observed with a median value of 3.46 fmol/mL (range, 0.34 to 8.67 fmol/mL) in patients with advanced carcinomas associated with thrombocytosis. These results indicate that thrombocytosis in patients with carcinomas might be caused, at least in part, by TPO produced by carcinoma cells.
巻・号 94(6)
ページ 1952-60
公開日 1999-9-15
PII S0006-4971(20)48902-5
PMID 10477724
MeSH Amino Acid Sequence Animals COS Cells DNA Transposable Elements Female Genetic Variation HeLa Cells Humans Molecular Sequence Data Protein Isoforms / biosynthesis Protein Isoforms / chemistry Protein Isoforms / genetics RNA, Messenger / genetics Recombinant Proteins / biosynthesis Recombinant Proteins / chemistry Reverse Transcriptase Polymerase Chain Reaction Sequence Alignment Sequence Deletion Thrombopoietin / biosynthesis Thrombopoietin / chemistry Thrombopoietin / genetics* Transcription, Genetic* Transfection Tumor Cells, Cultured
IF 17.794
引用数 31
WOS 分野 HEMATOLOGY
リソース情報
ヒト・動物細胞 HLC-1(RCB0083)