Circ_0001946 Promotes the Development of Acute Myeloid Leukemia by Upregulating PDL1

OBJECTIVE: Circ_0001946 has been identified as an oncogenic factor, and the aim of this study was to explore the detailed roles and putative targets of circ_0001946 in acute myeloid leukemia (AML). MATERIALS AND METHODS: Levels of circ_0001946 were examined in AML tissues and cells. Furthermore, the regulatory functions of circ_0001946 in AML were explored. The expression of circ_0001946 was evaluated in AML samples and a matched para-carcinoma control, as well as in AML cell lines and a human bone marrow stromal cell line using reverse transcription-quantitative polymerase chain reaction. Cell proliferation was examined using a CCK-8 kit, and migration/invasion was measured by transwell assay. Furthermore, interactions between associated molecules were assessed using RNA pulldown, and the mRNA stability of the relevant gene was examined by mRNA stability assay. RESULTS: Our data indicated that circ_0001946 was upregulated in AML specimens/cells. Additionally, overexpression of circ_0001946 promoted the proliferation, migration, and invasion of AML cells and, vice versa, these biological processes were suppressed by knockdown of circ_0001946. Furthermore, PDL1 is a potential downstream molecule of circ_0001946 in AML and its stability was improved by circ_0001946. The expression of PDL1 was increased in AML specimens and positively correlated with circ_0001946 expression. Moreover, biological behavioral alterations in AML cells induced by oe-circ_0001946 were abrogated by sh-PDL1 and the effects of sh-circ_0001946 were enhanced by treatment with sh-PDL1. CONCLUSION: Taken together, these data suggest that levels of circ_0001946 are elevated in AML and that circ_0001946 could promote the growth of AML cells. Furthermore, PDL1 is a novel downstream molecule of circ_0001946 in AML. Circ_0001946/PDL1 signaling may play crucial roles in tumor progression in AML and could be a novel candidate for targeted treatments for AML patients.