A novel metastatic promoter CEMIP and its downstream molecular targets and signaling pathway of cellular migration and invasion in SCLC cells based on proteome analysis.

PURPOSE: Metastasis is an unavoidable event happened among almost all small cell lung cancer (SCLC) patients. However, the molecular driven factors have not been elucidated. Recently, a novel hydrolase called cell migration inducing hyaluronidase (CEMIP) triggered both migration and invasion in many tumors but not SCLC. Therefore, in this study, we verified that CEMIP promoted migration and invasion in SCLC and applied proteomics analysis to screen out potential target profiles and the signaling pathway related to CEMIP regulation. METHOD: Immunofluorescence was conducted to exam the expression of CEMIP on SCLC and paired adjacent normal tissues among enrollment. RT-qPCR and Western blot (WB) assays were conducted to valuate cellular protein and mRNA expression of CEMIP and EMT markers. Lentivirus-CEMIP-shRNAs and CEMIP plasmid were used for expression manipulating. Changes of cellular migration and invasion were tested through transwell assays. Tandem Mass Tag (TMT) peptide labeling coupled with LC-MS/MS was used for quantifying proteins affected by reducing expression of CEMIP on H446 cells. RESULTS: The expression of CEMIP showed 1.64 ± 0.16-fold higher in SCLC tissues than their normal counterpart. Decreasing the expression of CEMIP on SCLC cells H446 regressed both cellular migration and invasion ability, whereas the promoting cellular migration and invasion was investigated through over-expressing CEMIP on H1688. Proteomic and bioinformatics analysis revealed that total 215 differentially expressed proteins (DEPs) that either their increasing or decreasing relative expression met threshold of 1.2-fold changes with p value ≤ 0.05. The dramatic up-regulated DEPs included an unidentified peptide sequence (encoded by cDNA FLJ52096) SPICE1 and CRYAB, while the expression of S100A6 was largely down-regulated. DEPs mainly enriched on caveolae of cellular component, calcium ion binding of biological process and epithelial cell migration of molecular function. KEGG enrichment indicated that DEPs mainly exerted their function on TGF-ß, GABAergic synapse and MAPK signaling pathway. CONCLUSION: It is the first report illustrating that CEMIP might be one of the metastatic triggers in SCLC. And also, it provided possible molecular mechanism cue and potential downstream target on CEMIP-induced cellular migration and invasion on SCLC.

Differential long noncoding RNAs expression in cancer-associated fibroblasts of non-small-cell lung cancer.

AIM: The aim of this study was to investigate the role of long noncoding RNAs (lncRNAs) profiles in cancer-associated fibroblasts (CAFs) during non-small-cell lung cancer (NSCLC) progression. MATERIALS & METHODS: Differentially expressed lncRNAs and mRNAs were detected by lncRNA microarray between three patient-paired CAFs and the adjacent normal fibroblasts, which were obtained from tumoral and nontumoral portions of surgically resected lung tissue from three primary NSCLCs. Bioinformatic analyses including gene ontology and pathway analysis were applied to these differentially expressed mRNAs. The qRT-PCR was conducted to identify the change of selected lncRNAs that might be involved in contribution of CAFs toward NSCLC. RESULTS: A total of 766 lncRNAs and 750 mRNAs abnormally expressed in CAFs (fold-change >2, p < 0.05). Bioinformatic analyses indicated that these mRNAs are associated with immune function. The qPCR results were consistent with microarray data. CONCLUSION: The lncRNAs profiles of CAFs may provide promising targets for further research on immune regulation during NSCLC process.