977P - Detection of leukemic stem cells in patients with de novo acute myeloblastic leukemia

Date 28 September 2014
Event ESMO 2014
Session Poster Display session
Topics Leukaemia
Translational Research
Presenter Manal Elmasry
Citation Annals of Oncology (2014) 25 (suppl_4): iv327-iv339. 10.1093/annonc/mdu339
Authors M.W. Elmasry
  • Clinical Pathology, Faculty of Medicine Cairo University, 1331 - Cairo/EG

Abstract

Aim

Defining the self-renewing [Thy1-, CD34 + , CD38-] LICs in AML cases before and after induction chemotherapy as a predictor for relapse and to determine how CSF1R (Fms) and CD34 markers affect the growth and survival of human leukemic cells in the CD38- Thy1- population.

Methods

This study was carried out on 30 samples from the peripheral blood of adult patients with de-novo acute myeloid leukemia. The majority of the patients were monocytic AML Samples were sorted into four populations (Fms + CD34-, Fms + CD34 + , Fms-CD34+ and Fms-CD34-) according to the surface markers of the cells. Cells were cultured on mouse stromal cells transfected with a plasmid containing human CSF-1. Samples were cultured using Iscove's modified Dulbecc's medium (IMDM).The cultures were assessed for survival of leukemic cells in days.

Results

The mean survival in days of the cells was 13.9 before chemotherapy and 14.1 after chemotherapy. The difference in growth was insignificant (p > 0.05). The Fms-CD34+ population in all but two samples tested had the longest survival time in culture.

Conclusions

Our results suggest that leukemic stem cells may survive chemotherapy mainly due to their quiescence. Human CSF-1 was shown to increase the number of leukemic cells in co-culture with mouse stroma after 5 weeks. A novel leukemic stem cell (Fms-CD34+) has been identified and is the cell responsible for the growth and maintenance of the leukemic bulk.

Disclosure

All authors have declared no conflicts of interest.