An NF90/long noncoding RNA-LET/miR-548k feedback amplification loop controls esophageal squamous cell carcinoma progression.

In our previous study we have found that miR-548k has oncogenic roles in esophageal squamous cell carcinoma (ESCC) via repressing long noncoding RNA (lncRNA)-LET and further upregulating nuclear factor 90 (NF90). However, the upstream factors controlling miR-548k expression are still unknown. In this study, we found NF90 directly binds pri-miR-548k, increases the stability of pri-miR-548k, and upregulates the expression of pri-miR-548k and miR-548k. Therefore, NF90, miR-548k and lncRNA-LET forms a feedback loop. Gain-of-function and loss-of-function assays demonstrated that in accordance with the roles of miR-548k, NF90 also promotes ESCC cell proliferation and migration. Furthermore, we verified the regulatory feedback loop between NF90, miR-548k, and lncRNA-LET. We found NF90 upregulated miR-548k and downregulated lncRNA-LET. miR-548k downregulated lncRNA-LET and upregulated NF90. lncRNA-LET downregulated NF90 and miR-548k. Through the reciprocal regulations between each other, the NF90/miR-548k/lncRNA-LET feedback loop controls the expressions of NF90 targets (HIF-1α and VEGF), miR-548k targets (KLF10 and EGFR), and lncRNA-LET target (p53). Further functional assays demonstrated that activation of the NF90/miR-548k/lncRNA-LET feedback loop via simultaneously overexpressing NF90 and miR-548k and simultaneously depleting lncRNA-LET significantly promotes ESCC cell proliferation and migration in vitro and ESCC tumor growth in vivo. Targeting the NF90/miR-548k/lncRNA-LET feedback loop via simultaneously depleting NF90 and miR-548k and simultaneously overexpressing lncRNA-LET significantly inhibits ESCC cell proliferation and migration in vitro and ESCC tumor growth in vivo. In summary, our findings identified a crucial oncogenic NF90/lncRNA-LET/miR-548k feedback amplification loop, which may be promising therapeutic targets for ESCC.

Lin J ，Chen Z ，Wu S ，Huang W ，Chen F ，Huang Z ... -  《Journal of Cancer》

Up-regulated miR-548k promotes esophageal squamous cell carcinoma progression via targeting long noncoding RNA-LET.

Dysregulated noncoding RNAs have been observed in diverse cancers. MIR458K is frequently amplified in esophageal squamous cell carcinoma (ESCC). However, the expression, clinical significances, and action mechanisms of miR-548k in ESCC are still unclear. In this study, we found that miR-548k is significantly up-regulated in ESCC tissues and cell lines. Up-regulated miR-548k expression is significantly correlated with advanced invasion depth, lymph node metastasis, advanced TNM stage, and poor overall survival. Gain-of- and loss-of-function assays demonstrated that miR-548k promotes the proliferation and migration of ESCC cells in vitro and tumor growth in vivo. Mechanistically, we found that miR-548k directly targets and represses the expression of long noncoding RNA-LET (lncRNA-LET), and further down-regulates p53 and up-regulates NF90. In addition, we found that lncRNA-LET is down-regulated and inversely correlated with miR-548k in ESCC. Down-regulated lncRNA-LET also indicated poor overall survival of ESCC patients. Functional assays demonstrated that lncRNA-LET inhibits the proliferation and migration of ESCC cells, and the effects of miR-548k on ESCC are dependent on the negative regulation of lncRNA-LET. In summary, our data revealed the critical roles of miR-548k-lncRNA-LET regulation axis in ESCC and suggested that the miR-548k-lncRNA-LET regulation axis may be promising prognostic biomarkers and therapeutic targets for ESCC.

Chen Z ，Lin J ，Wu S ，Xu C ，Chen F ，Huang Z ... -  《-》

The chromosome 11q13.3 amplification associated lymph node metastasis is driven by miR-548k through modulating tumor microenvironment.

Zhang W ，Hong R ，Li L ，Wang Y ，Du P ，Ou Y ，Zhao Z ，Liu X ，Xiao W ，Dong D ，Wu Q ，Chen J ，Song Y ，Zhan Q ... -  《Molecular Cancer》

HDAC3-Mediated Repression of LncRNA-LET Regulates Gastric Cancer Cell Growth Proliferation, Invasion, Migration, and Apoptosis via MiR-548k.

Zhang J ，Liu X ，Chen J ，Xia S ... -  《-》

Exosomal lncRNA ZFAS1 regulates esophageal squamous cell carcinoma cell proliferation, invasion, migration and apoptosis via microRNA-124/STAT3 axis.

Li Z ，Qin X ，Bian W ，Li Y ，Shan B ，Yao Z ，Li S ... -  《JOURNAL OF EXPERIMENTAL & CLINICAL CANCER RESEARCH》