DGCR8 promotes the metastasis in triple-negative breast cancer by epigenetically regulating TGF-ß.

OBJECTIVE: Breast cancer (BC) is one of the most ordinary fatal cancers. Recent studies have identified the vital role of genes in the development and progression of Tri-negative breast cancer (TNBC). In this research, DGCR8 was studied to identify how it functioned in the metastasis of TNBC. PATIENTS AND METHODS: DGCR8 expression of tissues was detected by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) in 50 TNBC patients. Wound healing assay and transwell assay were used to observe the changes in the biological behaviors of TNBC cells through knockdown or overexpression of DGCR8. In addition, qRT-PCR and Western blot assay were performed to discover the potential target protein of DGCR8 in TNBC. RESULTS: DGCR8 expression level in TNBC samples was higher than that of adjacent ones. Besides, the migration ability and invasion ability of TNBC cells were inhibited after DGCR8 was silenced, while they were promoted after DGCR8 was overexpressed. In addition, TGF-ß was downregulated after silencing of DGCR8 in TNBC cells, while TGF-ß was upregulated after overexpression of DGCR8 in TNBC cells. Furthermore, TGF-ß was upregulated in TNBC tissues, which was positively associated with DGCR8. CONCLUSIONS: Our study uncovers a new oncogene in TNBC and suggests that DGCR8 can enhance TNBC cell migration and invasion via targeting TGF-ß, which provides a novel therapeutic target for TNBC patients.

[Advances in osteoradionecrosis of nasopharynx after radiotherapy for nasopharyngeal carcinoma].

Radiation therapy is the first choice for the treatment of nasopharyngeal carcinoma. However, it is inevitable that nasopharyngeal mucosa and tissue will be damaged after radiotherapy of nasopharyngeal carcinoma, which will cause corresponding complications. Nasopharyngeal osteonecrosis is a serious complication. Up to now, there are few reports about nasopharyngeal osteonecrosis, and the underlaying pathological mechanism remains unclear. The potential theories include radiotherapy damage, infection and trauma, but also the " three H" principle of hypoxic hypocellular hypovascular tissue, as well as the theory of radio induced fibrosis. It is controversial about the treatment of nasopharyngeal osteonecrosis. It takes comprehensive treatment, including local treatment, systemic treatment, surgical treatment and other treatments. Among them, local treatment as nasopharyngeal debridement usually is first choice. We reviewed the pathological mechanism and treatment methods of nasopharyngeal osteonecrosis, in order to provide a reference for better prevention and treatment of it.