Objective. To investigate the differential protein profile of human lung squamous carcinoma (HLSC) and normal bronchial epithelium (NBE) and provide preliminary results for further study to explore the carcinogenic mechanism of HLSC.Methods. Laser capture microdissection (LCM) was used to purify the target cells from 10 pairs of HLSC tissues and their matched NHBE, respectively. A stable-isotope labeled strategy using iTRAQ, followed by 2D-LC/Q-STAR mass spectrometry, was performed to separate and identify the differential expression proteins.Results. A total of 96 differential expression proteins in the LCM-purified HLSC and NBE were identified. Compared with NBE, 49 proteins were upregulated and 47 proteins were downregulated in HLSC. Furthermore, the expression levels of the differential proteins including HSPB1, CKB, SCCA1, S100A8, as well as S100A9 were confirmed by western blot and tissue microarray and were consistent with the results of quantitative proteomics.Conclusion. The different expression proteins in HLSC will provide scientific foundation for further study to explore the carcinogenic mechanism of HLSC.
Abstract
Background In molecular level, competing endogenous RNAs (ceRNAs) regulates other RNA transcripts through competing for shared microRNAs (miRNA). miRNA negatively regulate gene expression at the levels of mRNAs stability and translation suppression. Methods We tested the mRNA level of miR-218-5p and RNASEH1-AS1 in clinical lung squamous cell carcinoma tissues by qRT-PCR. In the exploring of the role of miR-218-5p and RNASEH1-AS1 in the malignant phenotype of NCI-H520 cells, colony formation and MTT assay were used to test the cell viability and proliferation capability, trans-well invasion and wound healing assay were performed to examine the cell migration and invasion. ChIP assay was conducted to confirm the direct interact of POU2F1 and RNASEH1-AS1 promoter. Results In this investigation, we found that LncRNA RNASEH1-AS1 is up-regulated in human lung cancer, and serves as a miRNA sponge for hsa-miR-218-5p in human lung squamous carcinoma cells. lncRNA RNASEH1-AS1 facilitates growth and motility of lung squamous carcinoma cells, while miR-218-5p does the opposite. NET1 and POU2F1 are validated as direct and functional targets of miR-218-5p. The downregulation of miR-218-5p releases the suppression of NET1 and POU2F1. POU2F1 binds directly to the lncRNA-RNASEH1-AS1 promoter and acts as transcription factor to enhance the promoter activity of RNASEH1-AS1. Conclusion Above all, the positive feedback loop of RNASEH1-AS1/ hsa-miR-218-5p/ NET1/ POU2F1 can help us to understand the regulatory mechanism behind genesis and progression of human lung squamous carcinoma, possibly providing new biomarkers for its diagnosis and treatment.
Costunolide induces G1/S phase arrest and activates mitochondrial-mediated apoptotic pathways in SK-MES 1 human lung squamous carcinoma cells