OBJECTIVE: To investigate the role of DYRK1A in the cytarabine (Ara-C) resistance mechanism of acute myeloid leukemia (AML) cells. METHODS: Overexpression and silencing of DYRK1A gene in THP-1 cells were used to observe whether the sensitivity of THP-1 cells to Ara-C was altered. RT-PCR was used to detect the changes in mRNA expression of related genes during Ara-C transport or metabolism. Western blot and RT-PCR were used to detect SAMHD1 expression after regulating DYRK1A expression in Ara-C treated cells. Co-IP technology was used to detect the interaction between Cyclin L2, DYRK1A, and SAMHD1. RESULTS: Overexpression of DYRK1A decreased Ara-C sensitivity in THP-1 cells while silencing DYRK1A increased it. Overexpression and silencing of DYRK1A did not affect Ara-C transport or metabolic gene expression. Overexpression of DYRK1A could increase the expression of SAMHD1 protein in cells, while silencing DYRK1A reduced SAMHD1 expression. Cyclin L2 interacted with DYRK1A and SAMHD1 in THP-1 cells. CONCLUSION DYRK1A is involved in Ara-C resistance in AML cells, and its mechanism may be related to increased expression of SAMHD1 by interacting with Cyclin L2.
Humans ; Cytarabine/pharmacology* ; Protein-Tyrosine Kinases/metabolism* ; Leukemia, Myeloid, Acute ; Dyrk Kinases ; Drug Resistance, Neoplasm ; Protein Serine-Threonine Kinases/metabolism* ; SAM Domain and HD Domain-Containing Protein 1 ; Cell Line, Tumor

As the most common chromosomal disorder compatible to life, Down syndrome (DS) is caused by an extra copy of chromosome 21. Almost all DS patients have cognitive dysfunction. Therefore, it is important to study the underlying pathogenetic mechanism to elucidate its molecular basis. This article has provided a review for the molecular mechanisms of NRIP1 and DYRK1A genes, which have been closely associated with the cognitive dysfunctions of DS patients. It has also summarized the research progress on the mechanism of DS and development of new therapeutic strategies based on such studies, with an aim to provide insights into the prevention and treatment for the cognitive dysfunctions in DS patients.
Down Syndrome/psychology* ; Humans ; Protein-Tyrosine Kinases/genetics* ; Dyrk Kinases ; Protein Serine-Threonine Kinases/genetics* ; Cognition Disorders/etiology*