Regulation of cancerous progression and epithelial-mesenchymal transition by miR-34c-3p via modulation of MAP3K2 signaling in triple-negative breast cancer cells.

Emerging but limited data have evidenced an essential involvement of microRNAs (miRNAs) in the development and progression of triple negative breast cancer (TNBC), which empowers these small regulators as an innovative therapeutic approach, especially for this unique tumor subgroup still lacking an efficient and specific therapeutic target. Herein, we reported the down-regulation of miR-34c-3p level in TNBC tissues, and its expression was closely associated with estrogen receptor alpha (ERα), but not other receptors, in well-characterized breast cancer (BCa) cells. Functionally, ectopic expression of miR-34c-3p inhibited migration, invasion and epithelial-mesenchymal transition (EMT) in TNBC cells. From a mechanistic standpoint, bioinformatics coupled with luciferase and gain-of-function, loss-of-function assays showed that miR-34c-3p may regulate TNBC progression by directly targeting the 3'-untranslated region (UTR) of mitogen-activated protein kinase kinase kinase 2 (MAP3K2). Consistently, MAP3K2 overexpression could effectively rescue miR-34c-3p mimics-induced suppression of cell invasion and EMT. In light of these findings, miR-34c-3p may function as a tumor suppressor in regulating of TNBC invasiveness and EMT through negatively modulating MAP3K2 pathway. Future endeavor in this field may help to identify a novel biomarker to predict prognosis and response to therapy in TNBC.

Wu J ，Li WZ ，Huang ML ，Wei HL ，Wang T ，Fan J ，Li NL ，Ling R ... -  《-》

MicroRNA-455-3p promotes invasion and migration in triple negative breast cancer by targeting tumor suppressor EI24.

Li Z ，Meng Q ，Pan A ，Wu X ，Cui J ，Wang Y ，Li L ... -  《Oncotarget》

MiR-508-3p inhibits cell invasion and epithelial-mesenchymal transition by targeting ZEB1 in triple-negative breast cancer.

Guo SJ ，Zeng HX ，Huang P ，Wang S ，Xie CH ，Li SJ ... -  《-》

MiR-92b inhibited cells EMT by targeting Gabra3 and predicted prognosis of triple negative breast cancer patients.

Li YY ，Zheng XH ，Deng AP ，Wang Y ，Liu J ，Zhou Q ，Cheng GY ，Jiang Q ... -  《-》

Dual regulation by microRNA-200b-3p and microRNA-200b-5p in the inhibition of epithelial-to-mesenchymal transition in triple-negative breast cancer.

Rhodes LV ，Martin EC ，Segar HC ，Miller DF ，Buechlein A ，Rusch DB ，Nephew KP ，Burow ME ，Collins-Burow BM ... -  《Oncotarget》