Long noncoding RNA MEG3 decreases the growth of head and neck squamous cell carcinoma by regulating the expression of miR-421 and E-cadherin.

Maternally expressed 3 (MEG3), a long chain noncoding RNA (lncRNA), has verified its function as a suppressor in several kinds of cancers. However, the downstream mechanism of MEG3 in regulating the molecular mechanism of epithelial-mesenchymal transformation (EMT) in head and neck squamous cell carcinoma (HNSCC) progression demands further investigation. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to determine the expression level of MEG3 in HNSCC and adjacent normal tissues of 51 cases. Luciferase report assay was used to detect the correlation between miR-421 and MEG3, and miR-421 and E-cadherin in HNSCC cell lines. Cell invasion and proliferation capacity were assessed through transwell and CCK8 assays. Scratch wound assay was used to assess cell migration capacity. Firstly, this study demonstrated that the expression of MEG3 was significantly downregulated in HNSCC compared to adjacent normal tissues. Overexpressed MEG3 inhibited cell proliferation, migration, and invasion in vitro. Secondly, MEG3 upregulated the expression of E-cadherin, which was instead downregulated by miR-421. MiR-421 was negatively regulated by MEG3 in HNSCC. Therefore, MEG3 regulated EMT by sponging miR-421 targeting E-cadherin in HNSCC. This study indicated that the MEG3-miR-421-E-cadherin axis could be a new therapeutic target for HNSCC.

Ji Y ，Feng G ，Hou Y ，Yu Y ，Wang R ，Yuan H ... -  《Cancer Medicine》

LncRNA MEG3 inhibits cell epithelial-mesenchymal transition by sponging miR-421 targeting E-cadherin in breast cancer.

MEG3, a lncRNA, has been verified in several tumors to function as tumor suppressors including breast cancer development and progression, however, the expression pattern and underlying mechanisms of MEG3 involved in breast cancer progression is still need to be further explored. The expression of MEG3 was confirmed in 90 cases of breast cancer tissues compared to adjacent normal tissues by quantitative real-time polymerase chain reaction (qRT-PCR) analysis. The association between clinicopathological factors and MEG3 expression was evaluated by chi-square test. Kaplan-Meier curve and log rank test was performed to assess disease-free survival (DFS) and overall survival (OS) time in patients. CCK8 and transwell invasion assays were used to assess cell proliferation and invasion capacity. Luciferase report assay and RNA pull down assay were used to detect the association between miR-421 and MEG3 in breast cancer. In the study, we demonstrated that the expression of MEG3 was significantly down-regulated in breast cancer tissues compared to adjacent normal tissues. Reducing MEG3 expression was significantly associated with TNM stage and lymph nodes metastasis in patients. Survival analysis showed that lower MEG3 predicted a poor DFS and OS for patients. In vitro, we showed that up-regulated MEG3 inhibited cell proliferation and cell invasion capacities. We further revealed that endogenous miR-421 expression was negatively regulated by MEG3 in breast cancer cells and MEG3 regulated E-cadherin expression by sponging to miR-421 in breast cancer cells. Our results showed that MEG3/miR-421/E-cadherin regulatory axis may be a novel therapeutic target for breast cancer.

Zhang W ，Shi S ，Jiang J ，Li X ，Lu H ，Ren F ... -  《-》

Low expression of lncRNA MEG3 promotes the progression of oral squamous cell carcinoma by targeting miR-21.

Zhang LL ，Hu D ，Zou LH 《-》

Long Noncoding RNA LINC00460 Promotes Cell Progression by Sponging miR-4443 in Head and Neck Squamous Cell Carcinoma.

Li M ，Zhang X ，Ding X ，Zheng Y ，Du H ，Li H ，Ji H ，Wang Z ，Jiao P ，Song X ，Zhong Y ，Wu H ... -  《-》

LncRNA LINC00460 promotes EMT in head and neck squamous cell carcinoma by facilitating peroxiredoxin-1 into the nucleus.

Jiang Y ，Cao W ，Wu K ，Qin X ，Wang X ，Li Y ，Yu B ，Zhang Z ，Wang X ，Yan M ，Xu Q ，Zhang J ，Chen W ... -  《JOURNAL OF EXPERIMENTAL & CLINICAL CANCER RESEARCH》