الفهرس | Only 14 pages are availabe for public view |
Abstract Mammalian cyclins are actually a family of related genes that includes; D-type cyclins (D1, D2, and D3) and cyclin E, which are expressed maximally as the cells progress from G1 to S phase, and cyclin A and B type cyclins, which are expressed in other phases of the cell cycle. Cyclin D1 is thought to play an important role in tumorigenesis and tumor progression. Overexpression of cyclin D1 could lead to tumorigenesis by causing premature pRb phosphorylation and shortening of G1. Many studies were conducted to assess cyclin D1 expression in various malignancies, revealed that there is overexpression of cyclin D1 in a wide variety of malignancies including: parathyroid tumors, breast cancers, esophageal cancers, bladder cancers , cervical & vulvar cancers, non small cell lung cancer (NSCLC) , and head & neck squamous cell carcinomas (HNSCC). cyclin D1 may act as a prognostic marker for ALL and it is correlated with disease progression. On the other hand, the role and degree of cyclin D1 expression in acute myeloid leukemia is not clear. So, we planned this study to assess cyclin D1 expression in cases with de novo acute myeloid leukemia. To achieve this aim, we measured cyclin D1 expression at the protein level, using flow cytometric technique, in 40 patients with newly diagnosed acute myeloid leukemia and 10 patients with newly diagnosed acute lymphoblastic leukemia. In addition, 11 healthy subjects were investigated as a reference control group. In conclusion: ” There was a significant higher expression of cyclin D1 in ALL patients, however in AML patients, cyclin D1 expression was normal . ” Cyclin D1 expression might have no significant role in pathogenesis of acute myeloid leukemia, however it may have a role in leukomogenesis in acute lymphoblastic leukemia. |