MicroRNA‑509 targets PAX6 to inhibit cell proliferation and invasion in papillary thyroid carcinoma

Abstract

MicroRNAs (miRNAs/miRs) negatively regulate the expression of numerous genes and therefore contribute to the occurrence and development of papillary thyroid carcinoma (PTC). Hence, further investigation into the specific roles of miRNAs in PTC is valuable for developing effective therapeutic methods for patients with this disease. MiRNA-509 is dysregulated and serves pivotal roles in several types of human cancer; however, the expression and roles of miR-509 in PTC and its underlying mechanism require further investigation. In the present study, the expression of miR-509 in PTC tissues and cell lines was detected and the specific functions of miR-509 in the progression of PTC were investigated. Additionally, the molecular mechanisms underlying the action of miR-509 in PTC were determined. The present study demonstrated that miR-509 was significantly downregulated in PTC tissues and cell lines. MiR-509 upregulation inhibited the PTC cell proliferation and invasion. Mechanistically, paired box 6 (PAX6) was identified as a novel target of miR-509 in PTC cells. In clinical PTC samples, miR-509 was significantly overexpressed and inversely correlated with PAX6 expression. PAX6 restoration effectively reversed the inhibitory effects of miR-509 overexpression on PTC cell proliferation and invasion. These results demonstrated that miR-509 may act as a tumor suppressor in PTC by directly targeting PAX6. Thus, miR-509 may be a potential therapeutic target for the treatment of patients with PTC.

Exosomal circular RNA hsa_circ_007293 promotes proliferation, migration, invasion, and epithelial–mesenchymal transition of papillary thyroid carcinoma cells through regulation of the microRNA-653-5p/paired box 6 axis

“…PAX6 belongs to the PAX family and is a vital transcription factor in a variety of biological processes [ 42 ]. Other investigations have also supported PAX6 as an oncogene and have characterized its overexpression across numerous types of human cancers [ 43 , 44 ]. Moreover, its cancer-promoting effects can be regulated by miRNAs [ 43 , 45 , 46 ].…”

“…Other investigations have also supported PAX6 as an oncogene and have characterized its overexpression across numerous types of human cancers [ 43 , 44 ]. Moreover, its cancer-promoting effects can be regulated by miRNAs [ 43 , 45 , 46 ]. Here, our findings confirmed the inhibitory impact of miR-653-5p on PAX6 expression in PTC cells.…”

MicroRNAs in Papillary Thyroid Cancer: What Is New in Diagnosis and Treatment

“…MiR-375 downregulation was found to enhance ERBB2 gene expression according to Wang et al's study, whereas it was positively regulated in PTC according to Saiselet et al's study(94,145). MiR-509 inhibited the PAX6 gene expression and acted as a tumor suppressor, reported as downregulated in PTC by Zhang et al, while it was found to be upregulated in another study(94,146). MiR-98 was found to be positively expressed inLiu et al's study and negatively expressed in Suresh et al's study…”

lncRNA ZFPM2-AS1 promotes retinoblastoma progression by targeting microRNA miR-511-3p/paired box protein 6 (PAX6) axis

“…PAX6 is also involved in a variety of key biological processes, including cell proliferation, migration, adhesion, signal transduction in normal development and tumorigenesis [ 29 , 30 ]. PAX6 showed the most interactions in the largest network, and has been reported to be a cancer driver in various cancers including lung [ 31–33 ] breast [ 30 ], colon [ 34 , 35 ], liver [ 36 ], pancreatic [ 36 ], and thyroid cancers [ 37 ]. Studies have shown that forced expression of PAX6 induces the formation of retinal heterotopic tissue [ 38 ].…”