Evaluation of miRNA-155 as a Biomarker for Cancer Stem Cells and its Role in Chemotherapy Resistance in Iraqi Patients with Acute Myeloid Leukemia

Background: acute myeloid leukemia (AML) is characterized as an aggressive blood cancer with rapid growth of immature leukemic cells. It appears that each subtype of AML displays a distinct miRNA profile. miRNAs play a role in regulating gene expression that is implicated in AML pathogenesis. This study was designed to assess the level of miRNA-155 gene expression in relation to chemotherapy resistance in various AML patient groups, with the hope of developing a novel marker for targeted therapy and early diagnosis and prognosis of cancer stem cells in AML patient. Methods: 120 AML cases were studied. Based on chemotherapy stage, 40 patients were assigned to each group (newly diagnosed, under treatment, and relapsed). Baghdad Teaching Hospital (Iraq) provided the cases and samples from February 2022 to April 2023. This study also included 40 healthy controls. The qRT-PCR method, which uses the ∆Ct-value and fold change (2-∆∆Ct), was used to count the genes after they were standardized to the level of a housekeeping gene (U6). Results: in this study, significantly elevated levels of miRNA-155 were observed in AML patients compared to controls, with a higher fold change detected in the newly diagnosed group. Conclusions: upregulation of miRNA-155 is suggested to be linked to AML development and is strongly associated with the progression of leukemic stem cells. These results might serve as accurate predictors of AML and potential therapeutic targets for the elimination of LSCs.