Highly expressed ribosomal protein L34 predicts poor prognosis in acute myeloid leukemia and could be a potential therapy target

Abstract

B ackground: Acute myeloid leukemia (AML) is a devastating malignancy with great heterogeneity, novel prognostic biomarkers and therapy targets are needed to improve the precise management of AML patients. Increasing evidence has shown the role of RPL34, a ribosomal protein, in tumorigenesis and progression. However, the detailed expression status and clinical significance of RPL34 in AML are largely unknown. M ethods: The expression level of RPL34 was detected in bone marrow samples from both AML patients and AML cell lines. Then using recombinant shRNA-lentiviral vector, we analyzed the impact of RPL34 knockdown on cell proliferation, apoptosis and cell cycle distribution. Lastly, by analyzing public gene expression datasets (GSE12417 and GSE2191), we determined the prognostic role of RPL34 in AML. Results: The mRNA level of RPL34 was significantly elevated in AML bone marrow samples and cell lines. Patients with high level of RPL34 had inferior survival outcomes than their counterparts, and upregulation of RPL34 may mediate chemoresistance in AML. Through knockdown of RPL34 in HL-60 cell line, we found cell proliferation was inhibited, cell apoptosis was triggered, and cell cycle was arrested in S phase. Conclusions: The present study demonstrated that downregulation of RPL34 could inhibit cell proliferation, promote cell apoptosis, and induce cell cycle arrest in AML cell line HL-60. Also, its expression and clinical significance in AML patients was confirmed. All these findings suggest that RPL34 may be a potential novel therapy target in AML. Key words: Acute myeloid leukemia; ribosomal protein L34; biomarker; therapy target; chemoresistance