HIGH CDX2 GENE EXPRESSION PREDICTS INFERIOR PROGNOSIS IN ACUTE MYELOID LEUKEMIA PATIENTS WITH NORMAL CYTOGENETICES.

Background: The caudal-type homebox gene CDX2 plays an important role not only in normal hematopoiesis but also in leukemogenesis. It is one of the most frequent aberrantly expressed proto-oncogenes in human leukemias. Patients and Methods: We studied the expression level of CDX2 mRNA in 66 newly diagnosed cytogenetically normal acute myeloid leukemia (CN-AML) patients and 20 healthy controls by Real-Time Quantitative Reverse-Transcriptase Polymerase Chain Reaction (RTQ-PCR) to determine gene relation to patients clinical and laboratory findings at diagnosis and to determine its impact on patients' outcome. Results: CDX2 expression rates and expression levels were significantly higher in AML patients than in controls (p<0.001). CDX2 high expressors were significantly older (p=0.006), had higher TLC (p=0.001), lower platelets count (p=0.024) and had hepatosplenomegaly (p<0.001) and lymph node enlargement (p=0.004) more than CDX2 low expressors. CDX2 high expressors was associated with worse prognosis; worse CR rates, shorter OS,DFS and EFS than CDX2 low expressors. The difference were highly statistically significant (p<0.001) in all. Conclusion: CDX2 is highly expressed in CN-AML patients. It is associated with high tumor burden and unfavorable prognosis. Therefore, it could be added to the prognostic markers in CN-AML patients.