Association of lipoprotein lipase expression with TP53 gene polymorphisms in chronic lymphocytic leukemia cells

Expression of lipoprotein lipase (LPL) correlates with unmutated (UM) status of the variable region of the heavy chain of immunoglobulin (IGHV) genes, but the expression level of LPL in UM chronic lymphocytic leukemia (CLL) cases varies significantly.

To study the association of LPL expression with the genetic variants of the TP53 gene since both genes are involved in lipid metabolism.

Expression of LPL mRNA was measured in peripheral blood mononuclears of 45 CLL patients with UM IGHV genes by real-time quantitative reverse transcription polymerase chain reaction. Mutational status of IGHV genes and TP53 genotyping (rs1042522, rs1642785, rs17883323, rs2909430, rs145153611, rs113530090, rs12947788, rs12951053, and rs17878362) were performed by polymerase chain reaction amplification followed by direct sequencing.

Observed CLL patients were divided on groups with low (11.17 ± 2.66) and high (275.48 ± 39.37) LPL expression. In CLL patients with UM IGHV genes and low LPL expression we found an increased frequency of rs1042522 G (p = 0.0036), rs1642785 C (p = 0.0001), and rs17878362A2 alleles (p = 0.0091). The possible functional significance of these changes is discussed.

Some polymorphic variants of TP53 may be genetic modifiers for LPL expression level in CLL leukemic B-cells. Further research is required in a larger cohort to confirm these findings.