DNA polymerases (pol-d1 and pol-d2) expression of childhood leukemia

Objective: The aim of this study is to evaluate the prognostic value of flow cytometry and DNA Polymerases (PolD1 and PolD2) expression which are essential to DNA replication and repair and their interferance with other clinical pictures. Material and Method: Within the scope of this study, totally 101 cases that are diagnosed between January 2008 and November 2015 at "Çukurova University Faculty Of Medicine Balcalı Hospital" are taken into account. 73 of these cases have acute lymphoblastic leukemia (ALL) and 28 of them have acute myeloid leukemia (AML). DNA polymerases (PolD1 and PolD2) expression are examined via Real Time PCR at the time of diagnosis. Results: DNA polymerases' expression of ALL and AML patients are found statistically significant (p:0,001) when compared by control group. DNA polymerases' expression are significantly low, but they are not statistically significant (p>0,05) in the group of ALL patients who had relapse, central nervous system involvement or who past away during treatment. At the same time, DNA polymerases' expression of AML patients who had relapse or who past away are found to be significantly low, but they are not statistically significant (p>0,05). Effect of DNA polymerases' expression levels are divided into two groups (high and low) according to the 95th percentile of control group's mean, then its effect on survival is examined. ALL patients with high DNA PolD1 expression had 5 year survival rate of %68, ALL patients with low DNA PolD1 expression had 5 year survival rate of %54 respectively. ALL patients with high DNA PolD2 expression had 5 year survival rate of %68, ALL patients with low DNA PolD2 expression had 5 year survival rate of %58 as well. AML patients with high DNA PolD1 expression had 5 year survival rate of %80, AML patients with low DNA PolD1 expression had 4 year survival rate of %54. AML patients with high DNA PolD2 expression had 5 year survival rate of %88, AML patients with low DNA PolD2 expression had 5 year survival rate of %63. It seems probable that, the differences would be statistically signficant if the study could be implemented on greater amount of participants. Conclusion: DNA polymerases' expression of the patients -who had relapse, central nervous system involvement or who past away- that are measured during diagnosis are significantly low. At the same time, patients' survival rates are worse who had low DNA polymerase expression. Thus, it can be thought that evaluation of DNA polymerases' expression during diagnosis can be used as a poor prognostic factor. This paper seems to be the first study in literature that is about the expression of DNA polymerases' in acute childhood leukemia. Future study can be implemented on greater amount of cases to show the effects of DNA polymerases more clearly. Keywords: Acute leukemia, DNA polymerase, PolD1, PolD2, Prognosis.