Screening and validating circular RNAs that estimate disease risk and treatment response of pediatric acute myeloid leukemia: a microarray-based analyses and RT-qPCR validation

Abstract

Purpose: Circular RNA (circRNA) is a type of novel non-coding RNA with close involvement in the tumorigenesis and treatment response of leukemias. This study aimed to screen and validate candidate circRNAs that estimate disease risk and response to induction therapy of pediatric acute myeloid leukemia (AML).

Methods: Bone marrow samples were obtained from 4 complete response (CR) pediatric AML patients, 4 non-CR pediatric AML patients, and 4 controls to screen differentially expressed circRNAs (DECs) through microarray analyses. Ten candidate circRNAs were selected and validated in 40 pediatric AML patients and 10 controls through reverse transcription-quantitative polymerase chain reaction.

Results: Microarray assay discovered 378 upregulated DECs and 688 downregulated DECs in pediatric AML patients vs. controls; 832 upregulated DECs and 950 downregulated DECs in CR AML patients vs. non-CR AML patients. Then cross-analysis identified 441 DECs that both related to pediatric AML risk and CR achievement. Further validation of ten candidate circRNAs in larger sample-sized populations showed that circ_0032891, circ_0076995, circ_0014352, circ_0047663, circ_0007444, circ_0001684, circ_0000544, and circ_0005354 were related to pediatric AML risk; circ_0032891, circ_0076995, circ_0014352, circ_0047663, circ_0007444, circ_0001684, and circ_0000544 were related to CR achievement in pediatric AML patients. Regarding the correlation of candidate circRNAs with survival profile, only circ_0032891, circ_0076995, and circ_0000544 forecasted event-free survival; circ_0076995 and circ_0001684 estimated overall survival in pediatric AML patients.

Conclusion: CircRNA profile is intensively implicated in the disease risk and treatment response of pediatric AML, especially that circ_0032891, circ_0000544, circ_0076995, and circ_0001684 are related to pediatric AML risk, CR achievement, and survival.

Keywords: Circular RNA profile; Microarray; Pediatric acute myeloid leukemia; RT-qPCR validation; Treatment response.