[Ku80 Inhibition Affects the Chemotherapeutic Sensitivity of T-Acute Lymphoblastic Leukemia Cell Line Jurkat].

Objective: To investigate the influence of Ku80 inhibition on the chemotherapeutic sensitivity of the T-acute lymphoblastic leukemia(T-ALL) cell line Jurkat, and to explore the potential mechanism.

Methods: The transcription and expression level of Ku80 in 6 hematological malignant cell lines were detected by RT-qPCR and Western blot, respectively. The expression of Ku80 in Jurkat cells was detected by Western blot after transfection with the recombinant shKu80 lentiviral vector. The proliferation capacity of Jurkat cells was explored by CCK-8 after Ku80 inhibition. The colony formation ability, apoptosis, and γH2AX(a protein marker of DNA damage) expression in Jurkat cells were investigated after Ku80 silencing and co-treated with etoposide(VP16) for 4 hours through soft agar assay, flow cytometry and Western blot, respectively.

Results: The mRNA level and protein expression of Ku80 were both highest in Jurkat among 6 hematological malignant cell lines. Ku80 expression was successfully down regulated in Jurkat cells after relative plasmid transfected. The proliferative ability of cells was significantly decreased after Ku80 inhibition(P < 0.05). The colony formation capacity of Jurkat cells was obviously reduced and the cells apoptosis and γH2AX expression were increased after Ku80 inhibition, with or without VP16 incubation.

Conclusion: Targeted silencing of Ku80 could enhance the sensitivity of VP16 in Jurkat cells, which might be associated with the elevated level of DNA damage accumulation.