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Nasopharyngeal carcinoma (NPC) is a rare head and neck tumor that threatens people's health. Radiotherapy is a major treatment for NPC, however, radioresistance of the NPC cells may contribute to treatment failure. LncRNA SNHG16 was upregulated in NPC; however, the function of SNHG16 in radioresistant NPC cells remains unexplored. RT-qPCR was applied for detecting SNHG16, miR-31-5p and SFN levels. MTT assay and colony formation assay were applied to assess the cell viability and proliferation. Dual luciferase was applied for assessing the relation among SNHG16, miR-31-5p and SFN. SFN level in NPC cells was examined by Western blot. The level of SNHG16 and SFN in NPC cells was significantly upregulated by exposure to radiation. In addition, silencing of SNHG16 or miR-31-5p mimics notably attenuated radioresistance of NPC cells. SNHG16 could positively regulate the expression of SFN in NPC cells through binding with miR-31-5p. Furthermore, SNHG16 downregulation obviously attenuated the proliferation and radioresistance of NPC cells by regulation of miR-31-5p/SFN axis. Knockdown of lncRNA SNHG16 attenuates radioresistance of nasopharyngeal carcinoma cells by miR-31-5p/SFN axis. Thus, our research data show a novel method for improving the efficacy of radiotherapy for NPC. [ABSTRACT FROM AUTHOR]

In this study, a three‐dimensional large‐scale numerical model is established to investigate the failure characteristics of overlying strata and mechanism of strong ground pressure induced by excavation disturbance from multiple working faces. The characteristics of overlying strata fractures, heights of the caving zone and the fracture zone, and evolution of the stress field are systematically analyzed. The numerical simulation results reveal that the height of the caving zone after mining is 8.1 m, and that of the fracture zone is 27.3 m under the conditions of gently inclined thin coal seams. These findings are consistent with the theoretical results. The fracture development process can be divided into three stages: extensive development of new fractures, partial compaction of fractures, and closure of numerous fractures. In the structure of the post‐mining overlying rock, four stress zones are identified as follows: two zones of stress concentration at both ends of the working face, respectively, a zone of relatively high stress at the middle of the working face with low overlying strata, and a zone of stress fully released at the middle of the working face with high overlying strata. Comprehensive analysis of the maximum vertical stress of the cross section and the stress of the working face indicates that the stress increases significantly when mining enters the gob square stage and the roof does not collapse timely. [ABSTRACT FROM AUTHOR]