Display options
Share it on

J Cancer. 2012;3:354-61. doi: 10.7150/jca.4813. Epub 2012 Aug 24.

Heterogeneity of p53-pathway Protein Expression in Chemosensitive Chronic Lymphocytic Leukemia: A Pilot Study.

Journal of Cancer

Michael J Groves, Stephanie F Maccallum, Michael T Boylan, Sally Haydock, Joan Cunningham, Keith Gelly, Duncan Gowans, Ron Kerr, Philip J Coates, Sudhir Tauro

Affiliations

  1. 1. Dundee Cancer Centre, University of Dundee, Ninewells Hospital and Medical School, Dundee, Scotland, United Kingdom. DD19SY;

PMID: 22962562 PMCID: PMC3434363 DOI: 10.7150/jca.4813

Abstract

The presence of p53-pathway dysfunction in chronic lymphocytic leukemia (CLL) can be used to identify patients with chemotherapy-refractory disease. Therapeutic responses are known to vary between patients with chemosensitive CLL and may relate to differences in p53-pathway activity. We hypothesized that the magnitude or type of p53-pathway protein expression is heterogeneous in patients with chemosensitive disease and could associate with white cell responses. In this pilot study, changes in p53 and its transcriptional targets, p21/waf1 and MDM2 were analyzed by immunoblotting and densitometry in CLL cells from 10 patients immediately prior to the start of chemotherapy, and after culture for 24 hours (h) with fludarabine (n=7) or chlorambucil (n=3). The in vitro response was also compared to that in vivo in circulating cells pre-treatment, and at 24h and 96h of chemotherapy. Disease responses were evident in all patients after the first treatment-cycle. Significant p53 induction was observed in CLL cells treated in vitro and in vivo. Greater heterogeneity in the expression-intensity was observed in vivo (σ2=45.15) than in vitro (σ2=1.33) and the results failed to correlate (r(2)=0.18, p=0.22). p21/waf1 and MDM2 expression-profiles were also dissimilar in vitro and in vivo. Higher in vivo (but not in vitro) responses associated with changes in white cell count (p=0.026). Thus, heterogeneity of p53-pathway activity exists in chemosensitive CLL; in unselected patients, in vivo changes do not correlate with those in vitro, but may associate with post-treatment white cell responses.

Keywords: CLL; in vitro.; in vivo; p53

References

  1. Lancet. 2010 Oct 2;376(9747):1164-74 - PubMed
  2. Blood. 2001 Aug 1;98(3):814-22 - PubMed
  3. Blood. 2004 Sep 1;104(5):1428-34 - PubMed
  4. Blood. 2007 Aug 15;110(4):1116-22 - PubMed
  5. Genes Dev. 1996 Oct 1;10(19):2438-51 - PubMed
  6. Lancet. 2004 Jan 10;363(9403):105-11 - PubMed
  7. Best Pract Res Clin Haematol. 2010 Mar;23(1):71-84 - PubMed
  8. Cold Spring Harb Perspect Biol. 2009 Nov;1(5):a001883 - PubMed
  9. Cancer Res. 2010 Dec 1;70(23):9808-15 - PubMed
  10. Cancer Res. 2009 Jun 15;69(12):5210-7 - PubMed
  11. Leuk Lymphoma. 1994 Dec;16(1-2):31-6 - PubMed
  12. Mol Cancer. 2010 May 26;9:123 - PubMed
  13. Br J Haematol. 2004 Nov;127(4):425-8 - PubMed
  14. J Pathol. 2003 Nov;201(3):377-88 - PubMed
  15. EMBO J. 1996 Sep 2;15(17):4566-73 - PubMed
  16. J Pathol. 2005 Jan;205(2):221-35 - PubMed
  17. Blood. 2010 Jan 14;115(2):187-97 - PubMed
  18. Blood. 2008 Jun 15;111(12):5446-56 - PubMed
  19. Am J Hematol. 1997 Mar;54(3):189-95 - PubMed
  20. Blood. 2009 Sep 24;114(13):2589-97 - PubMed
  21. Nat Rev Mol Cell Biol. 2003 Jan;4(1):33-45 - PubMed
  22. Mol Cancer. 2010 May 20;9:115 - PubMed
  23. Lancet. 2007 Jul 21;370(9583):230-239 - PubMed
  24. J Clin Oncol. 2007 Dec 1;25(34):5448-57 - PubMed
  25. Nature. 2000 Nov 16;408(6810):307-10 - PubMed
  26. Br J Haematol. 2004 May;125(3):294-317 - PubMed
  27. Cell. 2008 Jul 11;134(1):62-73 - PubMed
  28. Blood. 2009 Dec 17;114(26):5307-14 - PubMed
  29. Blood. 2008 Oct 15;112(8):3322-9 - PubMed

Publication Types