ABSTRACT
<p><b>OBJECTIVE</b>To study the effect of LSD1 knock-out on human chronic myeloid leukemia cells(K562 cells).</p><p><b>METHODS</b>The LSD1 gene in K562 cells was knocked-out specifically by using CRISPR/Cas9 system, the single cells were gained by flow cytometric sorting technique, the LSD1and LSD1cell lines were gained after amplificantion and culture, identification of Western blot and sequencing. The MTS assay was used to detect the effect of LSD1 knockout on the proliferation of K562 cells, the flow cytometry was used to examine the expression of K562 cell surface marker after LSD1 knockout.</p><p><b>RESULTS</b>The LSD1 stable knockout cell line of K562 (LSD1and LSD1)were successfully costructed. It was found that knockout of LSD1 significantly inhibited the proliferation of K562 and the expression of CD235a.</p><p><b>CONCLUSION</b>LSD1 plays a key role in the regulation of K562 cell proliferation and CD235a expression.</p>