LAUSR

Long noncoding RNAs (lncRNAs) have been found to play an important role in the occurrence and development of endometrial carcinoma (EC). Here, using RNA sequencing analysis, we systemically screened and identified the lncRNA eukaryotic translation initiation factor 1A, X‐linked (EIF1AX)‐AS1, which is aberrantly downregulated in clinical EC tissues and closely correlated with tumor type. EIF1AX‐AS1 markedly inhibited EC cell proliferation and promoted apoptosis in vitro and in vivo. Mechanistically, EIF1AX‐AS1 interacts with EIF1AX mRNA and poly C binding protein 1 (PCBP1), which promote EIF1AX mRNA degradation. Intriguingly, by interacting with internal ribosome entry site‐related protein Y‐box binding protein 1 (YBX‐1), EIF1AX promotes c‐Myc translation through the internal ribosome entry site pathway. c‐Myc promotes EIF1AX transcription and thus forms a feed‐forward loop to regulate EC cell proliferation. Taken together, these data reveal new insights into the biology driving EC proliferation and highlights the potential of lncRNAs as biomarkers for prognosis and future therapeutic targets for cancer.