Overexpression of geranylgeranyl diphosphate synthase contributes to tumour metastasis and correlates with poor prognosis of lung adenocarcinoma.

This study aimed to evaluate the biological role of geranylgeranyl diphosphate synthase (GGPPS) in the progression of lung adenocarcinoma. GGPPS expression was detected in lung adenocarcinoma tissues by qRT-PCR, tissue microarray (TMA) and western blotting. The relationships between GGPPS expression and the clinicopathological characteristics and prognosis of lung adenocarcinoma patients were assessed. GGPPS was down-regulated in SPCA-1, PC9 and A549 cells using siRNA and up-regulated in A549 cells using an adenoviral vector. The biological roles of GGPPS in cell proliferation, apoptosis, migration and invasion were determined by MTT and colony formation assays, flow cytometry, and transwell and wound-healing assays, respectively. In addition, the regulatory roles of GGPPS on the expression of several epithelial-mesenchymal transition (EMT) markers were determined. Furthermore, the Rac1/Cdc42 prenylation was detected after knockdown of GGPPS in SPCA-1 and PC9 cells. GGPPS expression was significantly increased in lung adenocarcinoma tissues compared to that in adjacent normal tissues. Overexpression of GGPPS was correlated with large tumours, high TNM stage, lymph node metastasis and poor prognosis in patients. Knockdown of GGPPS inhibited the migration and invasion of lung adenocarcinoma cells, but did not affect cell proliferation and apoptosis. Meanwhile, GGPPS inhibition significantly increased the expression of E-cadherin and reduced the expression of N-cadherin and vimentin in lung adenocarcinoma cells. In addition, the Rac1/Cdc42 geranylgeranylation was reduced by GGPPS knockdown. Overexpression of GGPPS correlates with poor prognosis of lung adenocarcinoma and contributes to metastasis through regulating EMT.

NCAPG2 promotes tumour proliferation by regulating G2/M phase and associates with poor prognosis in lung adenocarcinoma.

NCAPG2 is a component of the condensin II complex and contributes to chromosome segregation via microtubule-kinetochore attachment during mitosis. It is well known that NCAPG2 plays a critical role in cell mitosis; however, the role of altered NCAPG2 expression and its transcriptional regulatory function in cancer development remains mostly unknown. Here, for the first time we reported that NCAPG2 was evidently increased in non-small cell lung cancer tissues compared to adjacent normal lung tissues. Clinicopathological data analysis showed that NCAPG2 overexpression was significantly correlated with lymph node metastasis and pathologic-Tumour Nodes Metastasen stages, and was an independent prognostic factor in lung adenocarcinoma patients. Moreover, siRNA-mediated knockdown of NCAPG2 could inhibit tumour cell growth of lung adenocarcinoma cells (A549 and H1299) in vitro and could significantly lead to cell cycle arrest in the G2 phase. Furthermore, we found that NCAPG2 silencing significantly decreased the expression levels of G2/M phase cell cycle-related protein expressions (Cyclin B1, Cdc2) and increased the expression levels of p27 and p21 through Western blot analysis. Taken together, we demonstrated that increased NCAPG2 expression could regulate cell proliferation and identified as a poor prognostic biomarker in lung adenocarcinoma.

PRC1 contributes to tumorigenesis of lung adenocarcinoma in association with the Wnt/ß-catenin signaling pathway.

BACKGROUND: Protein regulator of cytokinesis-1 (PRC1) belongs to the microtubule-associated proteins (MAPs) family, and is involved in cytokinesis. Recent investigations suggest PRC1 involvement in human carcinogenesis, including breast carcinoma, hepatocellular carcinoma and etc. However, whether PRC1 contributes to lung adenocarcinoma tumorigenesis remains unknown. METHODS: Quantitative reverse-transcription polymerase chain reaction (qRT-PCR), Western blotting and Immunohistochemical staining (IHC) were used to evaluate and contrast the PRC1 expression profile in lung adenocarcinoma and adjacent normal lung tissues. We examined the clinical use of PRC1 in lung adenocarcinoma prognosis. Additionally, the tumorigenesis impact of PRC1 in lung adenocarcinoma cells was verified via in vitro and in vivo metastasis and tumorigenesis assays. Notably, Next Generation Sequencing (NGS) was performed to investigate the molecular mechanism underlying the oncogenic role of PRC1 in lung adenocarcinoma. RESULTS: PRC1 mRNA and protein expressions were upregulated in lung adenocarcinoma tissues compared to adjacent normal lung tissues. PRC1 protein overexpression correlated with lymph node metastasis and was an independent poor prognostic factor for lung adenocarcinoma patients. Our data implied that PRC1 depletion limited the proliferation and invasion of lung adenocarcinoma cells in vitro and lowered tumor development and lung metastasis in vivo. Remarkably, limiting PRC1 substantially prompted G2/M phase cell cycle arrest and apoptosis. Mechanistically, by conducting NGS on PRC1-depleted A549 cells and control cells, we discovered that PRC1 expression was significantly correlated with the Wnt signaling pathway. CONCLUSIONS: This investigation offers confirmation that PRC1 is a prognostic and promising therapeutic biomarker for people with lung adenocarcinoma and takes on a key part in the activation of the Wnt/ß-catenin pathway in lung adenocarcinoma development.

Comparison between endobronchial ultrasound-guided transbronchial biopsy and CT-guided transthoracic lung biopsy for the diagnosis of peripheral lung cancer: a systematic review and meta-analysis.

BACKGROUND: With the release of the National Lung Screening Trial results, the detection of peripheral pulmonary lesions (PPLs) is likely to increase. Computed tomography (CT)-guided percutaneous transthoracic needle biopsy (PTNB) and radial probe endobronchial ultrasound (r-EBUS)-guided transbronchial lung biopsy (TBLB) are recommended for tissue diagnosis of PPLs. METHODS: A systematic review of published literature evaluating the accuracy of r-EBUS-TBLB and CT-PTNB for the diagnosis of PPLs was performed to determine point sensitivity and specificity, and to construct a summary receiver-operating characteristic curve. RESULTS: This review included 31 publications dealing with EBUS-TBLB and 14 publications dealing with CT-PTNB for the diagnosis of PPLs. EBUS-TBLB had point sensitivity of 0.69 (95% CI: 0.67-0.71) for the diagnosis of peripheral lung cancer (PLC), which was lower than the sensitivity of CT-PTNB (0.94, 95% CI: 0.94-0.95). However, the complication rates observed with EBUS-TBLB were lower than those reported for CT-PTNB. CONCLUSIONS: This meta-analysis showed that EBUS-TBLB is a safe and relatively accurate tool in the investigation of PLC. Although the yield remains lower than that of CT-PTNB, the procedural risks are lower.

Prognostic value of the expression of estrogen receptor ß in patients with non-small cell lung cancer: a meta-analysis.

BACKGROUND: Lung cancer remains the leading cause of cancer-related deaths in men and the second leading cause in women worldwide. It is becoming increasingly clear that estrogen and estrogen receptors are involved in the pathogenesis and development of lung cancer. However, observational studies on the prognostic role of estrogen receptor ß (ERß) in non-small cell lung cancer (NSCLC) are controversial. METHODS: To clarify the impact of ERß in NSCLC survival, we performed this meta-analysis that included eligible studies. The combined hazard ratios (HR) and their corresponding 95% confidence intervals (CIs) were calculated in terms of overall survival. RESULTS: A total of eleven studies with 3,300 patients were evaluable for this meta-analysis. Our results suggested that ERß overexpression had no relationship on survival of patients with NSCLC, the HR (95% CI) was 1.000 (0.954-1.047) overall. Moreover, there was no heterogeneity between the studies. CONCLUSIONS: ERß overexpression indicates no relationship of prognosis for patients with NSCLC.