Novel nude mice model of human NK/T cell lymphoma were established by subcutaneously injecting two NK/T cell lymphoma cell lines into the right axillary region of mice and successful passages were completed by injecting cell suspension which was obtained through a 70-μm cell strainer. These mice models and corresponding cell clones have been successfully developed for more than 8 generations. The survival rates of both resuscitation and transplantation in NKYS and YT models were 90% and 70% correspondingly. Pathologically, the tumour cells in all passages of the lymphoma-bearing mice and cell lines obtained from tumours were parallel to initial cell lines. Immunologically, the tumour cells expressed the characteristics of the primary and essential NK/T lymphomas. The novel mice models maintained the essential features of human NK/T cell lymphoma, and they would be ideal tools in vivo for further research of human NK/T cell lymphoma.

miR-516a-3p has been reported to play a suppressive role in several types of human tumours. However, the expression level, biological function and fundamental mechanisms of miR-516a-3p in breast cancer remain unclear. In the present study, we found that miR-516a-3p expression was down-regulated and Pygopus2 (Pygo2) expression was up-regulated in human breast cancer tissues and cells. Through analysing the clinicopathological characteristics, we demonstrated that low miR-516a-3p expression or positive Pygo2 expression was a predictor of poor prognosis for patients with breast cancer. The results of a dual luciferase reporter assay and Western blot analysis indicated that Pygo2 was a target gene of miR-516a-3p. Moreover, overexpression of miR-516a-3p inhibited cell growth, migration and invasion as well as epithelial-mesenchymal transition (EMT) of breast cancer cells, whereas reduced miR-516a-3p expression promoted breast cancer cell growth, migration, invasion and EMT. Furthermore, we showed that miR-516a-3p suppressed cell proliferation, metastasis and EMT of breast cancer cells by inhibiting Pygo2 expression. We confirmed that miR-516a-3p exerted an anti-tumour effect by inhibiting the activation of the Wnt/β-catenin pathway. Finally, xenograft tumour models were used to show that miR-516a-3p inhibited breast cancer cell growth and EMT via suppressing the Pygo2/Wnt signalling pathway. Taken together, these results show that miR-516a-3p inhibits breast cancer cell growth, metastasis and EMT by blocking the Pygo2/ Wnt/β-catenin pathway.