Molecular mechanism of G1 arrest and cellular senescence induced by LEE011, a novel CDK4/CDK6 inhibitor, in leukemia cells

Yan-Fang Tao; Na-Na Wang; Li-Xiao Xu; Zhi-Heng Li; Xiao-Lu Li; Yun-Yun Xu; Fang Fang; Mei Li; Guang-Hui Qian; Yan-Hong Li; Yi-Ping Li; Yi Wu; Jun-Li Ren; Wei-Wei Du; Jun Lu; Xing Feng; Jian Wang; Wei-Qi He; Shao-Yan Hu; Jian Pan

doi:10.1186/s12935-017-0405-y

Molecular mechanism of G₁ arrest and cellular senescence induced by LEE011, a novel CDK4/CDK6 inhibitor, in leukemia cells

Cancer Cell Int. 2017 Mar 6:17:35. doi: 10.1186/s12935-017-0405-y. eCollection 2017.

Authors

Yan-Fang Tao¹, Na-Na Wang², Li-Xiao Xu¹, Zhi-Heng Li¹, Xiao-Lu Li¹, Yun-Yun Xu¹, Fang Fang¹, Mei Li¹, Guang-Hui Qian¹, Yan-Hong Li¹, Yi-Ping Li¹, Yi Wu¹, Jun-Li Ren², Wei-Wei Du², Jun Lu², Xing Feng¹, Jian Wang¹, Wei-Qi He³, Shao-Yan Hu², Jian Pan¹

Affiliations

¹ Institute of Pediatrics, Children's Hospital of Soochow University, Suzhou, China.
² Department of Hematology and Oncology, Children's Hospital of Soochow University, Suzhou, China.
³ CAM-SU Genomic Resource Center, Soochow University, Suzhou, China.

Abstract

Background: Overexpression of cyclin D1 dependent kinases 4 and 6 (CDK4/6) is a common feature of many human cancers including leukemia. LEE011 is a novel inhibitor of both CDK4 and 6. To date, the molecular function of LEE011 in leukemia remains unclear.

Methods: Leukemia cell growth and apoptosis following LEE011 treatment was assessed through CCK-8 and annexin V/propidium iodide staining assays. Cell senescence was assessed by β-galactosidase staining and p16^INK4a expression analysis. Gene expression profiles of LEE011 treated HL-60 cells were investigated using an Arraystar Human LncRNA array. Gene ontology and KEGG pathway analysis were then used to analyze the differentially expressed genes from the cluster analysis.

Results: Our studies demonstrated that LEE011 inhibited proliferation of leukemia cells and could induce apoptosis. Hoechst 33,342 staining analysis showed DNA fragmentation and distortion of nuclear structures following LEE011 treatment. Cell cycle analysis showed LEE011 significantly induced cell cycle G₁ arrest in seven of eight acute leukemia cells lines, the exception being THP-1 cells. β-Galactosidase staining analysis and p16^INK4a expression analysis showed that LEE011 treatment can induce cell senescence of leukemia cells. LncRNA microarray analysis showed 2083 differentially expressed mRNAs and 3224 differentially expressed lncRNAs in LEE011-treated HL-60 cells compared with controls. Molecular function analysis showed that LEE011 induced senescence in leukemia cells partially through downregulation of the transcriptional expression of MYBL2.

Conclusions: We demonstrate for the first time that LEE011 treatment results in inhibition of cell proliferation and induction of G₁ arrest and cellular senescence in leukemia cells. LncRNA microarray analysis showed differentially expressed mRNAs and lncRNAs in LEE011-treated HL-60 cells and we demonstrated that LEE011 induces cellular senescence partially through downregulation of the expression of MYBL2. These results may open new lines of investigation regarding the molecular mechanism of LEE011 induced cellular senescence.

Keywords: Arraystar Human LncRNA array; CDK4/6; Cellular senescence; LEE011; Leukemia.