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Background: Platinum-based chemotherapy is the main treatment for advanced lung squamous cell carcinoma (LUSC). Eventually, patients with LUSC develop resistance to cisplatin, which affects the prognosis. Hence, the researchers sought to find a lncRNA in LUSC that affects resistance to cisplatin. Methods: The lncRNA microarray assay was used to screen the differential expression of lncRNA. qPCR was used to detect lncRNA DSCAS (DSCAS) expression in tissues and cell lines. Lentiviral transfection was used to regulate the expression of DSCAS. CCK-8, colony formation, wound healing, transwell, and flow cytometry assays were used to assess the biological behaviors and sensitivity to cisplatin of LUSC cell. RNA-RNA interaction was tested using the dual luciferase reporting assay, RNA-IP, and RNA-RNA pull-down assay. The downstream pathway of DSCAS was verified by qPCR and Western blotting assays. Results: DSCAS was highly expressed in LUSC tissues and cells, and its expression levels were higher in cisplatin-insensitive tissues than in cisplatin-sensitive tissues. Elevation of DSCAS promoted cell proliferation, migration and invasion as well as increased cisplatin resistance of lung cancer cells, while demotion of DSCAS inhibited cell proliferation, migration and invasion as well as decreased the cisplatin resistance of lung cancer cells. DSCAS bound to miR-646-3p to regulate the expression of Bcl-2 and Survivin, which affected the cell apoptosis and sensitivity to cisplatin in LUSC cells. Conclusions: DSCAS regulates biological behavior and cisplatin sensitivity in LUSC cells by competitively binding to miR-646-3p to mediate the expression of Survivin and Bcl-2, known as apoptosis-related proteins.

Lonicera japonica (L. japonica) is utilized as foods and healthy drink around the world. Until now, the immunomodulatory activity of polysaccharides from L. japonica (LJP) is little studied. In our previous work, LJP was fractionated to a neutral component (LJP-N) and an acidic component (LJP-A) by a DEAE-Cellulose column, and LJP-N was a starch-like polysaccharide and LJP-A was a pectic polysaccharide. In this study, LJP-N and LJP-A were investigated for their immunomodulatory effect, and the protective effect of these two polysaccharide fractions against immune injury by cyclophosphamide (CTX) in BALB/c mice was evaluated. Results showed that when compared with CTX group, LJP fractions, especially for LJP-A (200 mg kg−1) can enhance the immune function, improve atrophy of the lymphoid organs thymus and spleen (the increased approximately 1.8- and 1.6-fold), increase the phagocytic function of macrophages (increased approximately 1.7-fold), increase the secretion of cytokines (the levels of IL-6, IL-2, and TNF-α increased approximately 2.5-, 2.0-, and 1.4-fold) and immunoglobulins levels (the levels of IgM and IgG increased approximately 1.2- and 1.7-fold) in serum, and enhance the cytotoxic activity of NK cells (increased approximately 3.5-fold). Taken together, the present results suggest that LJP-A, rich in uronic acid, with a molecular weight of 400 kDa, may be a potential candidate as the functional foods.