Alterations in microRNAs expression have been proposed to play role in 
endometrial cancer pathogenesis. Dicer and Drosha are main regulators of 
microRNA biogenesis and deregulation of their expression has been indicated as a 
possible cause of microRNAs alterations observed in various cancers. The 
objective of this study was to investigate Dicer and Drosha genes expression in 
endometrial cancer and to analyze the impact of clinicopathological 
characteristics on their expression. Fresh tissue samples were collected from 44 
patients (26 endometroid endometrial carcinoma and 18 controls). Clinical and 
pathological data were acquired from medical documentation. Dicer and Drosha 
genes expressions were assessed by qRT-PCR using validated reference genes. 
Dicer and Drosha expression levels were significantly lower in endometrial 
cancer samples comparing to controls. Dicer was down-regulated by the factor of 
1.54 (p=0.009) and Drosha gene mean expression value was 1.4 times lower in 
endometrial cancer group versus control group (p=0.008). Down-regulation of 
Dicer significantly correlated with decreased expression of Drosha (coefficient 
value 0.75). Decreased expression of Drosha correlated with higher histological 
grade and was influenced by BMI. Lower Dicer expression was found in nulli- and 
uniparous females comparing to multiparous individuals (p=0.002). Neither the 
FIGO stage nor the menstrual status had significant influence on the expression 
of studied genes. This study revealed for the first time that expression 
alterations of main regulators of microRNAs biogenesis are present in 
endometrial cancer tissue and could be potentially responsible for altered 
microRNAs profiles observed in this malignancy.