Production of thrombopoietin by human carcinomas and its novel isoforms

Yutaka Sasaki, Takayuki Takahashi, Hiroshi Miyazaki, Atsushi Matsumoto, Takashi Kato, Kishiko Nakamura, Sumiko Iho, Yoshiaki Okuno, Kazuwa Nakao

研究成果: Article

39 引用 (Scopus)

抜粋

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.

元の言語English
ページ(範囲)1952-1960
ページ数9
ジャーナルBlood
94
発行部数6
出版物ステータスPublished - 1999 9 15
外部発表Yes

ASJC Scopus subject areas

  • Biochemistry
  • Immunology
  • Hematology
  • Cell Biology

フィンガープリント Production of thrombopoietin by human carcinomas and its novel isoforms' の研究トピックを掘り下げます。これらはともに一意のフィンガープリントを構成します。

  • これを引用

    Sasaki, Y., Takahashi, T., Miyazaki, H., Matsumoto, A., Kato, T., Nakamura, K., Iho, S., Okuno, Y., & Nakao, K. (1999). Production of thrombopoietin by human carcinomas and its novel isoforms. Blood, 94(6), 1952-1960.