The relationship of telomere and telomerase activity with outcome of aplastic anemia after immunosuppressive therapy

Abstract

To observe the changes of telomere length and telomerase activity in patients with aplastic anemia (AA), and relationship with immunosuppressive therapy (IST) efficacy, to explore the pathogenesis of AA and the role of telomere length in evaluating immunosuppressive therapy efficacy. 71 cases of AA patients between September 2010 and March 2013 were enrolled into this study. 3 ml peripheral blood specimens from this cohort of patients were collected to test the telomere length in peripheral blood mononuclear cell (PBMNC) with flow-FISH and detect telomerase activity with TRAP-PCR-ELISA method. Telomere length and age showed negative correlation (b=-0.387, P=0.001) in normal control, NSAA and SAA + VSAA groups, telomere length became shorter with the growth of age, and normal control group telomere length decreased along with the age growth slightly greater than the other two groups (NSAA, SAA+VSAA). Besides the effect of age on telomere length, no significant difference was observed between NSAA and SAA+VSAA groups (P=0.573), and NSAA, SAA+VSAA (30.957 ± 4.502,29.510 ± 5.911)groups were significantly shorter than normal control group (51.086±10.844) (P<0.01). Telomere length in NR group (25.357±4.848)was significantly lower than normal control group (51.086 ± 10.844) (P=0.005), telomere length in CR(32.808 ± 4.685)/PR groups (30.334±4.464) compared with normal control group had no significant difference (P=0.517, P=0.254). Telomere length below 29.21% obviously decreased outcomes of IST. Telomerase activity had significant difference (χ²=20.385, P<0.01). The telomerase activity had no significant difference in terms of age and gender in three groups, multiple comparison found that telomerase activities in SAA + VSAA (0.324±0.178) (P<0.01), and NSAA (0.234±0.175) groups (P=0.002) were significantly higher than normal control group (0.107±0.083). Telomere length of PBMNC in AA patients was significantly shortened than normal control group with telomerase activity increased, and telomere shorted more apparently in NR group, these patients should adjust the treatment as early as possible. Telomeres could predict the curative effect of IST.