Human LPP gene is fused to MLL in a secondary acute leukemia with a t(3;11) (q28;q23).
The mixed lineage leukemia, MLL, gene is frequently rearranged in patients with secondary leukemia following treatment with DNA topoisomerase II inhibitors. By FISH and Southern blot analyses we identified a rearrangement in the MLL gene due to a novel t(3;11)(q28;q23) chromosomal translocation in a patient who developed AML-M5 3 years after treatment for a follicular lymphoma. Through inverse PCR, the LPP (lipoma preferred partner) gene on 3q28 was identified as the MLL fusion partner. LPP contains substantial identity to the focal adhesion protein, zyxin, and is frequently fused to HMGIC in lipomas. The breakpoint occurred in intron 8 of MLL and LPP. Two in-frame MLL-LPP transcripts, which fuse MLL exon 8 to LPP exon 9, were detected by RT-PCR, although the smaller of these contained a deletion of 120 bp from the MLL sequence. The predicted MLL-LPP fusion protein includes the A/T hook motifs and methyltransferase domain of MLL joined to the two last LIM domains of LPP. A reciprocal LPP-MLL transcript, predicted to include the proline-rich and leucine zipper motifs, and the first LIM domain of LPP were also detected by RT-PCR. In summary, LPP is a newly identified MLL fusion partner in secondary leukemia resulting from topoisomerase inhibitors. The MLL-LPP and LPP-MLL predicted proteins contain many of the features present in other MLL rearrangements.
Dahéron
L
L
Laboratoire d'Hématologie (CNRS FRE 2224), Poitiers University Hospital, CHU La Miletrie BP577, 86021 Poitiers Cedex, France.
Veinstein
A
A
Brizard
F
F
Drabkin
H
H
Lacotte
L
L
Guilhot
F
F
Larsen
C J
CJ
Brizard
A
A
Roche
J
J
D000328:Adult; D000595:Amino Acid Sequence; D001483:Base Sequence; D019457:Chromosome Breakage / Q000235:genetics; D002880:Chromosomes, Human, Pair 11 / Q000235:genetics; D002893:Chromosomes, Human, Pair 3 / Q000235:genetics; D003001:Cloning, Molecular; D003598:Cytoskeletal Proteins / Q000235:genetics*; D004268:DNA-Binding Proteins / Q000235:genetics*; D017809:Fatal Outcome; D005260:Female; D011495:Histone-Lysine N-Methyltransferase; D006801:Humans; D007621:Karyotyping; D060588:LIM Domain Proteins; D007948:Leukemia, Monocytic, Acute / Q000139:chemically induced / Q000235:genetics*; D008224:Lymphoma, Follicular / Q000188:drug therapy / Q000235:genetics*; D008969:Molecular Sequence Data; D051788:Myeloid-Lymphoid Leukemia Protein; D016609:Neoplasms, Second Primary / Q000139:chemically induced / Q000235:genetics*; D015514:Oncogene Proteins, Fusion / Q000235:genetics*; D011519:Proto-Oncogenes; D012333:RNA, Messenger / Q000235:genetics; D014157:Transcription Factors; D014178:Translocation, Genetic / Q000235:genetics*
D003598:Cytoskeletal Proteins; D004268:DNA-Binding Proteins; C497422:KMT2A protein, human; D060588:LIM Domain Proteins; C103594:LPP protein, human; D015514:Oncogene Proteins, Fusion; D012333:RNA, Messenger; D014157:Transcription Factors; D051788:Myeloid-Lymphoid Leukemia Protein; D011495:Histone-Lysine N-Methyltransferase