Exosomal lncRNA NEAT1 from cancer-associated fibroblasts facilitates endometrial cancer progression via miR-26a/b-5p-mediated STAT3/YKL-40 signaling pathway

Cancer-associated fibroblasts cells (CAFs) confer a rapid growth and metastasis ability of endometrial cancer (EC) via exosomes-mediated cellular communication. Long non-coding RNA nuclear enriched abundant transcript 1 (lncRNA NEAT1) drives the malignant phenotypes of EC cells. However, the role of exosomal NEAT1 from CAFs in EC progression remains ambiguous, which needs to be investigated. In our study, NEAT1 and YKL-40 were up-regulated, while miR-26a/b-5p was down-regulated in EC tissues. Moreover, NEAT1 expression was increased in CAF-exosomes compared with that in NF-exosomes. In addition, the exosomal NEAT1 derived from CAFs could transfer to EC cells and promote YKL-40 expression. Further exploration showed that exosomal NEAT1 enhanced YKL-40 expression via regulating miR-26a/b-5p-STAT3 axis in EC cells. More importantly, exosomal NEAT1 accelerated in vivo tumor growth via miR-26a/b-5p-STAT3-YKL-40 axis. Taken together, our study reveals that exosomal NEAT1 from CAFs contributes to EC progression via miR-26a/b-5p-mediated STAT3/YKL-40 pathway, which indicates the therapeutic potential of exosomal NEAT1 for treating EC.