miRNA‐301b‐3p accelerates migration and invasion of high‐grade ovarian serous tumor via targeting CPEB3/EGFR axis

High‐grade ovarian serous carcinoma (HGS‐OvCa), a type of ovarian cancer with poor prognosis due to distant metastasis, is urgently in need of new therapeutic targets. microRNAs (miRNAs), a class of small noncoding RNAs, perform significant roles in tumor progression. Mounting evidence has revealed the aberrant expression of miRNA in various cancers, one of which is HGS‐OvCa. Present study planned to investigate that miRNA‐301b‐3p accelerates migration and invasion of high‐grade ovarian serous tumor via targeting CPEB3/EGFR axis. Upregulation of miR‐301b‐3p was uncovered in HGS‐OvCa tissues and cell lines, and was identified to be associated with metastasis. The Kaplan‐Meier analysis confirmed the association of miR‐301b‐3p with poor prognosis of HGS‐OvCa patients. Transwell assay validated the oncogenic effect of miR‐301b‐3p on migration and invasion of HGS‐OvCa cells. Cytoplasmic polyadenylation element binding protein 3 (CPEB3) was then identified as a target of miR‐301b‐3p. It was also discovered that CPEB3 was downregulated in HGS‐OvCa tissues and cell lines. The Spearman correlation curve presented the negative correlation of CPEB3 expression with miR‐301b‐3p. Furthermore, rescue assays proved that miRNA‐301b‐3p regulated the invasion and migration through CPEB3. Western blot and qRT‐PCR analysis showed that miRNA‐301b‐3p induced epidermal growth factor receptor and downstream metastasis‐related proteins, p38, and extracellular signal‐regulated kinase 1/2 (ERK1/2), through CPEB3. To be concluded, these results indicated that miRNA‐301b‐3p accelerated migration and invasion of high‐grade ovarian serous tumor via targeting CPEB3/EGFR axis. microRNA‐301b‐3p (miR‐301b‐3p) is upregulated in high‐grade ovarian serous carcinoma (HGS‐OvCa) tissues and cell lines and is related to metastasis as well as prognosis in HGS‐OvCa patients. miR‐301b‐3p is a promoter for HGS‐OvCa metastasis, and knockdown of miR‐301b‐3p inhibited migration and invasion of HGS‐OvCa cells. Cytoplasmic polyadenylation element binding protein 3 (CPEB3) is directly targeted by miR‐301b‐3p, and is downregulated in HGS‐OvCa tissues and cells. The role of miR‐301b‐3p/CPEB3 in HGS‐OvCa cell migration and invasion. miR‐301b‐3p regulates mitogen‐activated protein kinase signaling through CPEB3 in HGS‐OvCa.