Fig. 7.

Cytoplasmic HOTAIRM1 regulates the miR-152-3p/ULK3 axis to promote leukemia cell autophagy and proliferation. a Venn diagram showing the number of common miRNAs (score > 0.9) targeting the HOTAIRM1 3’UTR predicted by two bioinformatics software tools. b Relative levels of candidate miRNAs in OCI-AML3 cells transfected with shHOTAIRM1. c-d miR-152-3p expression levels in OCI-AML3 (c) and OCI-AML2 + NPM1-mA (d) cells transfected with the HOTAIRM1 expression vector. e Correlation of HOTAIRM1 expression with miR-152-3p expression in 14 NPM1-mutated AML samples. f Survival analysis based on miR-152-3p expression in NPM1-mutated AML samples using TCGA data. g Luciferase reporter assays were used to detect luciferase activity in HOTAIRM1-WT/Mut-transfected HEK293T. h The correlation between miR-152-3p and ULK3 RNA expression levels was analyzed in the TCGA AML dataset by using starBase. i Expression level of ULK3 in primary AML blasts without (n = 20) and with NPM1 mutation (n = 14). j Luciferase reporter assays were used to detect luciferase activity in ULK3-WT/Mut-transfected HEK293T. k-l Relative ULK3 mRNA and protein expression in OCI-AML3 cells after transfection with the miR-152-3p mimic (k) and in OCI-AML2 cells after transfection with the miR-152-3p inhibitor (l). m-n Western blot analysis of ULK3 levels in the different transfection groups of HOTAIRM1-silenced OCI-AML3 cells after miR-152-3p downregulation (m) and in HOTAIRM1-overexpressing OCI-AML2 cells after miR-152-3p upregulation (n). The data are presented as the mean ± SD of three independent experiments. *P < 0.05, **P < 0.01, ***P < 0.001. n.s. indicates no significant difference