TLX3 rearrangements, t(5;14)
Most chromosomal translocations observed in T-cell acute lymphoblastic leukemia (T-ALL) often produce transcriptional activation of transcription factor oncogenes. Ectopic expression of the TLX3 (also known as HOX11L2) gene, located in 5q35, has been shown to be associated with a cryptic t(5;14)(q35;q32) specific translocation for a subtype of T-ALL. t(5;14)(q35;q32) is found in 20% of T-ALL cases in children and adolescents, whose leukemic cells mostly have normal karyotypes. This chromosomal rearrangement is thought to produce an abnormal TLX3 gene control by CTPI2, located in 14q32.
TLX3 overexpression in T-ALL is strongly associated with the presence of genomic rearrangements, and t(5;14)(q35; q32) has been associated with poor prognosis by some studies.
References
- Bernard OA, et al. (2001) Leukemia; 15 (10) : 1495-1504.
