Molecular analysis of a HTLV-IpX defective human adult T-cell leukemia

Leuk Res. 1992 Sep;16(9):941-6. doi: 10.1016/0145-2126(92)90040-e.


Fresh and cultured leukemia cells from an adult T-cell leukemia (ATL) patient which possessed gag and env gene defective human T-cell leukemia virus type I (HTLV-I) provirus genome were molecularly analyzed. Cells from both fresh and the established cell line, named KB-1 showed identical surface markers of helper T cells, expressed the interleukin 2 (IL-2) receptor and had an identical defective HTLV-I provirus genome with deletions of the gag and env genes involving pX gene exon 2. The KB-1 cells grew vigorously in vitro, even in the absence of IL-2 and the culture supernatant of KB-1 contained a large amount of IL-2. Neither pX mRNA nor p40(TAX) protein was detected in the KB-1 cells. The collective evidence suggests that the pX gene was not functioning in this particular ATL case. The biological function of the HTLV-I genes, especially the pX gene is discussed in relation to the early and late leukemogenesis of ATL.

Publication types

  • Case Reports
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Blotting, Southern
  • Chromosome Deletion*
  • DNA, Neoplasm / analysis*
  • DNA, Viral / analysis*
  • Genes, env / genetics*
  • Genes, gag / genetics*
  • Genes, pX / genetics*
  • Human T-lymphotropic virus 1 / genetics*
  • Humans
  • Leukemia-Lymphoma, Adult T-Cell / genetics*
  • Male
  • Middle Aged
  • Tumor Cells, Cultured


  • DNA, Neoplasm
  • DNA, Viral