Novel miRNA-based biomarker panel for detection β2-agonists in goats

miR‑451 suppresses the malignant characteristics of colorectal cancer via targeting SAMD4B

Cancer metastasis and recurrence are major causes of poor survival in patients with colorectal cancer (CRC). Therefore, the biological behavior of microRNA (miR)‑451 in CRC deserves further investigation. Reverse transcription‑quantitative PCR was applied to measure the relative expression of miR‑451 in blood serum specimens from patients with CRC and CRC cells. In vitro, HCT116 cells were transfected with miR‑451 mimics, a miR‑451 inhibitor, or SAMD4B plasmids. Proliferation, migration and apoptosis were measured using CCK‑8, Transwell assays and flow cytometry, respectively. Luciferase reporter assay was used to identify targets of miR‑451 and western blotting performed to explore the internal mechanisms of miR‑451 regulation. In vivo, the effect of miR‑451 and SAMD4B plasmids on tumor growth was analyzed using a nude mouse xenograft model. Results indicated that serum miR‑451 expression was lower in patients with CRC compared with healthy controls. Patients with elevated expression of miR‑451 had longer survival times compared with those with low expression. Overexpression of miR‑451 inhibited proliferation and migration, promoted apoptosis and enhanced the sensitivity of CRC cells to chemotherapy. SAMD4B was identified as a direct target of miR‑451 using miRNA target prediction programs and dual luciferase reporter assay validated the binding site of miR‑451 in the 3‑'UTR region of SAMD4B. Further studies confirmed that miR‑451 inhibited CRC progression via targeting SAMD4B. Results indicated that miR‑451 is essential for blocking tumor growth via targeting SAMD4B in vivo and in vitro. The miR‑451/SAMD4B axis may serve as a novel therapeutic target in patients with CRC.

miR-451a inhibits cancer growth, epithelial-mesenchymal transition and induces apoptosis in papillary thyroid cancer by targeting PSMB8

Despite the increasing incidence of papillary thyroid cancer in the past decade, the molecular mechanism underlying its progression remains unknown. Several studies have reported down-regulation of miR-451a or circular miR-451a in papillary thyroid cancer cell lines or patients. However, the underlying molecular mechanism remains unknown. In this study, we found that overexpression of miR-451a could inhibit proliferation, epithelial-mesenchymal transition and induce apoptosis in papillary thyroid cancer cells. Proteasome subunit beta type-8 was predicted to be a direct target of miR-451a and was validated with a luciferase reporter assay. Further functional assays showed that miR-451a could inhibit thyroid cancer progression by targeting proteasome subunit beta type-8.