Proliferation and apoptosis does not affect presenting white cell count in childhood ALL.
BACKGROUND
Treatment response/drug resistance in childhood acute lymphoblastic leukaemia (ALL) is related to presenting white cell count. This relationship might be explained by high proliferation fraction or by absence of significant apoptosis, but is presently unknown.


OBJECTIVE
To study the relationship between proliferation and apoptosis in childhood ALL.


METHODS
1.3.1. Study Groups. Thirty consecutive, unselected cases of childhood ALL (15M,15F). White cell count varied from 1-200 at presentation. 1.3.2. Proliferation/Apoptosis Fraction. Immunocytochemical detection of Ki-67 (MM1, NovaCastra, UK) on 5 microns paraffin slides, Immunocytochemical detection of apoptosis specific DNA (Klenow) fragments by labelling of 3'-OH ends in 10 microns paraffin sections (Frag-EL, CalBiochem, USA). 1.3.3. Quantitation. Image analysis (Quantimet 570C) using nuclear size bias correcting counting frame and rule. Calculation of proliferation (%Ki-67) fraction and of apoptosis corrected proliferation fraction (%Ki-67/100-%apoptosis).


RESULTS
Using both linear, logarithmic regression as well as power analysis, no relationship between variables was detected.


CONCLUSIONS
Presenting white cell count is not related to apoptotic or cell proliferative activity or to net tumour growth defined by the balance between these two processes. The relationship to treatment resistance still requires explanation.
Pyesmany
A F
AF
Department of Clinical Haemato-Oncology, Dalhousie University, IWK Grace Health Centre, Halifax, Nova Scotia, Canada.
Ball
L M
LM
Yhap
M
M
Henry
M
M
Laybolt
K
K
Riddell
D C
DC
van Velzen
D
D
D000293:Adolescent; D017209:Apoptosis; D001854:Bone Marrow Cells / Q000473:pathology*; D002455:Cell Division; D002648:Child; D002675:Child, Preschool; D053938:DNA Fragmentation; D005260:Female; D006801:Humans; D007223:Infant; D019394:Ki-67 Antigen / Q000032:analysis; D007958:Leukocyte Count; D008297:Male; D008940:Mitotic Index; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000097:blood* / Q000473:pathology*; D012044:Regression Analysis
D019394:Ki-67 Antigen