Nucleolar and spindle associated protein 1 enhances chemoresistance through DNA damage repair pathway in chronic lymphocytic leukemia by binding with RAD51

Purpose: Nucleolar and spindle associated protein 1 (NUSAP1), serves as a microtubule binding protein in chromosome separation, spindle assembly, and plays significant role to ensure normal regulation of cell cycle as well. This experiment aimed to document the NUSAP1 expression and functions in chronic lymphocytic leukemia (CLL). Methods: Lentivirus vectors either encoding shNUSAP1 or empty lentiviral vector were stably transfected into MEC-1 cells. 3 shNUSAP1 transfected and 3 shControl transfected MEC-1 cell samples were performed RNA sequencing (RNA-seq) analysis, functional enrichment analyses of gene ontology (GO) and gene set enrichment analysis (GSEA). Results: Silencing NUSAP1 inhibited the cell proliferation, promoted cell apoptosis and G0/G1 phase arrest. Mechanistically, high expression of NUSAP1 strengthened DNA damage repairing with RAD51 engagement. Our results also indicated that NUSAP1 knockdown suppressed the growth of CLL cells in vivo. Conclusion: Our research investigates the mechanism by which NUSAP1 enhances chemoresistance via DNA damage repair signaling by stabilizing RAD51 in CLL cells. Hence, NUSAP1 may be expected to be a perspective target for the treatment of CLL with chemotherapy resistance. RNA profiles of three test and three control samples were generated by deep sequencing, using Illumina HiSeq 4000.