Lung cancer, especially non-small cell lung cancer (NSCLC), is the leading cause of cancer-related mortality in the world. Both microRNAs and epidermal growth factor receptor (EGFR) are important factors in NSCLC. In our study, the expression of miR-30b in 47 tumor tissues and paired normal tissues of NSCLC were detected by RT-PCR, and we found that miR-30b was down-regulated in NSCLC tumor tissues and was associated with TNM stage, differentiation, and lymph node metastases. Then we investigated the ability of miR-30b to regulate EGFR in several NSCLC cell lines, and found that miR-30b inhibited proliferation, migration and invasion, induced apoptosis and enhanced sensitivity of the NSCLC cells to EGFR tyrosine kinase inhibitors (EGFR-TKIs) by targeting EGFR and repressing EGFR signaling pathways. Overall, these results indicate that miR-30b may be a potential therapeutic target in NSCLC patients.

The important functions of long non-coding RNAs in the malignancy of non-small cell lung cancer (NSCLC) has been increasingly highlighted. However, whether LINC01748 functions in a crucial regulatory role still requires further research. The aim of the present study was to investigate the biological roles of LINC01748 in NSCLC. Furthermore, different experiments were utilized to investigate the mechanism of action of LINC01748 in 2 NSCLC cell lines. Reverse transcription-quantitative PCR was used to measure mRNA expression levels. Cell Counting Kit-8 assay, flow cytometry analysis and Transwell and Matrigel assays were also used to analyze, cell viability, apoptosis, and migration and invasion, respectively. A tumor xenograft model was used for in vivo experiments. RNA immunoprecipitation experiments, luciferase reporter assays and rescue experiments were used to investigate the mechanisms involved. Data from The Cancer Genome Atlas dataset and patients recruited into the present study showed that LINC01748 was overexpressed in NSCLC. Patients with high LINC01748 mRNA expression level had shorter overall survival rate compared with that in patients with low LINC01748 mRNA expression level. Then, knockdown of LINC01748 mRNA expression level reduced cell proliferation, migration and invasion, but increased cell apoptosis in vitro . Knockdown of LINC01748 also reduced tumor growth in vivo . Mechanistically, LINC01748 could act as a competing endogenous (ce)RNA to sponge microRNA(miR)-520a-5p, to increase the expression level of the target gene, high mobility group AT-hook 1 (HMGA1) in the NSCLC cell lines. Furthermore, rescue experiments illustrated that the functions exerted by LINC01748 knockdown were negated by miR-520a-5p inhibition or HMGA1 overexpression. In summary, LINC01748 acted as a ceRNA by sponging miR-520a-5p, leading to HMGA1 overexpression, thus increasing the aggressiveness of the NSCLC cells. Accordingly, targeting the LINC01748/miR-520a-5p/HMGA1 pathway may benefit NSCLC therapy.

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Compared with other materials, high-volume fraction aluminum-based silicon carbide composites (hereinafter referred to as SiCp/Al) have many advantages, including high strength, small change in the expansion coefficient due to temperature, high wear resistance, high corrosion resistance, high fatigue resistance, low density, good dimensional stability, and thermal conductivity. SiCp/Al composites have been widely used in aerospace, ordnance, transportation service, precision instruments, and in many other fields. In this study, the ABAQUS/explicit large-scale finite element analysis platform was used to simulate the milling process of SiCp/Al composites. By changing the parameters of the tool angle, milling depth, and milling speed, the influence of these parameters on the cutting force, cutting temperature, cutting stress, and cutting chips was studied. Optimization of the parameters was based on the above change rules to obtain the best processing combination of parameters. Then, the causes of surface machining defects, such as deep pits, shallow pits, and bulges, were simulated and discussed. Finally, the best cutting parameters obtained through simulation analysis was the tool rake angle γ0 = 5°, tool clearance angle α0 = 5°, corner radius r = 0.4 mm, milling depth ap = 50 mm, and milling speed vc= 300 m/min. The optimal combination of milling parameters provides a theoretical basis for subsequent cutting.