Animals ; Humans ; Lung Neoplasms ; genetics ; pathology ; MicroRNAs ; genetics ; physiology ; Neoplasm Metastasis ; genetics ; pathology

BACKGROUND AND OBJECTIVEIt has been reported that defective expression of TGFBR3 was found in non-small cell lung cancer (NSCLC). However, its molecular mechanisms remain unclear. The aim of this study is to investigate expression of TGFBR3 in NSCLC cell lines and normal human bronchial epithelial cell (HBEpiC), and to explore potential molecular mechanisms underlying inactivation of TGFBR3 gene.

METHODSWestern blot was performed to determine the expression of TGFBR3 in HBEpiC and NSCLC cell lines. Automatic image analysis was carried out to estimate relative expression of TGFBR3 protein. We screened for mutation of the promoter region of TGFBR3 gene using DNA direct sequencing. Bisulfite-sodium modification sequencing was used to detect the methylation status of TGFBR3 promoter.

RESULTSTGFBR3 protein level was abnormally reduced in NSCLC cell lines as compared with HBEpiC. There was significant difference in TGFBR3 expression between the highly metastatic cell line 95D and non-metastatic cell lines, including LTEP-alpha-2, A549 and NCI-H460. No mutation and methylation was found in upstream sites -165 to -75 of the proximal promoter of TGFBR3 in HBEpiC and NSCLC cell lines. Hypermethylation was shown in upstream sites -314 to -199 of the distal promoter of TGFBR3 in HBEpiC and NSCLC cell lines.

CONCLUSIONReduced expression of TGFBR3 was observed in NSCLC cell lines, especially in 95D, suggesting that TGFBR3 might play an important role in development and progression of NSCLC and correlate with NSCLC invasion and migration. The methylation event occurring at TGFBR3 promoter is not a major cause for reduction of TGFBR3 expression.

Carcinoma, Non-Small-Cell Lung ; etiology ; genetics ; pathology ; Cell Line, Tumor ; DNA Methylation ; Gene Expression Regulation, Neoplastic ; Humans ; Lung Neoplasms ; etiology ; genetics ; pathology ; Mutation ; Promoter Regions, Genetic ; Proteoglycans ; genetics ; Receptors, Transforming Growth Factor beta ; genetics

Intracellular nutrients and the rate of energy lfowing in tumor cells are otfen higher than that in normal cells due to the prolonged stress of tumor-speciifc microenvironment. In this context, the metabolism of tumor cells provides the fuel of bio-synthesis and energy required for tumor metastasis. Consistent with this, the abnormal metabolism such as extremely active glucose metabolism and excessive accumulating of fatty acid is also discovered in metastatic tumors. Previous Studies have conifrmed that the regulation of tumor metabolism can affect the tumor metastasis, and some of these have been successfully applied in clinical effective, positive way. hTus, targeting metabolism of tumor cells might be an effectively positive way to prevent the metastasis of tumor. So, our review is focused on the research development of the relationship between tu-mor metabolism and metastasis as well as the underlying mechanism.

Background and objective Our previous study found that nicotine could induce lung cancer cell epithelial-mesenchymal transition (EMT). The aim of this study is to explore the relationship between nicotine-induced EMT and lung cancer invasion and metastasis. Methods Real-time PCR and Western blot were used to detect the expression changes of EMT-related markers, E-cadherin and Vimentin, in A549 lung cancer cells treated with nicotine;hTe transposition ofβ-catenin protein expression was determined by immunolfuorescence;Scratch test and Transwell invasion assay were used to detect the effects of nicotine on lung cancer cell migration and invasion. Results Nicotine can signiifcantly down-regulate the expressional level of E-cadherin mRNA and protein of A549 cells in a manner of dose and time-dependent (P<0.01, P<0.01);Nicotine can signiifcantly up-regulate the expressional level of Vimentin mRNA and protein of A549 cells in a manner of dose and time-dependent (P<0.01, P<0.01);Immunolfuorescence results showed thatβ-catenin protein was signiifcantly transfered to nucleus;Scratch test and Transwell assay showed that Nicotine could remarkably increase the migration and invasion poten-tial of lung cancer cells (P<0.01, P<0.01). Conclusion Nicotine can induce cancer cells EMT, and promote the invasion and metastasis ability of lung cancer cells.

Background and objective Cisplatin is the ifrst-line drug for the chemotherapy of non-small cell lung cancer (NSCLC), but the acquired chemoresistance restricted the effect of its treatment. hTe aim of this study is to validate the miRNAs related to the Cisplatin resistance in lung cancer and elucidate the molecular mechanisms. Methods We performed miRNA microarray and RT-PCR to obtain the aberrant differential expressed miRNAs between A549 and its paired Cisplatin-resistant cell line A549/DDP cells, and then we investigated the biological functions of miR-192, which is the aberrant differen-tial expressed miRNA. Atfer transfection of the miR-192 into A549 cells, we measured the half inhibition concentration (IC50), cell apoptosis of the trasfectant cells, and then we used biological sotfwares and dual-luciferase report assay to explore the target gene of the miR-192, which was further validated by RT-PCR and Western blot. Result MiR-192 was highly over-expressed in A549/DDP cells , whose quantity was 37.59±0.35 fold higher than that in A549 cells. Overexpression of miR-192 in A549 cells signiifcantly conferred resistance to Cisplatin and inhibited apoptosis. By contrast, down-expression of miR-192 in A549/DDP cells remarkably restrained the Cisplatin resistance and induced apoptosis. MiR-192 binded to Bim 3’-UTR and negatively regulated Bim expression at the post-transcriptional level in lung adenocarcinoma cells. Conclusion Our data suggested that miR-192 induced Cisplatin-resistance and inhibited cell apoptosis in lung cancer via negative targeting Bim expression.