Prospective validation of quantitative NSE mRNA in pleural fluid of non-small cell lung cancer patients

Knockdown of neuron-specific enolase suppresses the proliferation and migration of NCI-H209 cells

Neuron-specific enolase (NSE) is generally considered as a marker for diagnosis and evaluation of the response to therapy in small cell lung cancer (SCLC). However, the role of NSE in the progression of SCLC remains to be elucidated. In the present study, the functions of NSE in SCLC, in addition to the potential mechanisms, were investigated using a loss-of-function approach with NSE-targeting small interfering (si)RNA. The knockdown of NSE markedly decreased the proliferation of NCI-H209 cells, as indicated by MTT assay (P<0.05). Furthermore, the silencing of NSE resulted in the formation of smaller and fewer colonies compared with that in the control group (P<0.001). Flow cytometric analysis indicated that the silencing of NSE resulted in a decreased S-phase population among NCI-H209 cells (P<0.05). Transwell assay demonstrated that the silencing of NSE suppressed the migration of NCI-H209 cells (P<0.001). NCI-H209 cells transfected with NSE siRNA-1 or negative control were collected and the protein levels of metastasis-associated genes were detected using western blot analysis. The results indicated that the knockdown of NSE led to downregulation of the pro-metastatic gene vascular endothelial growth factor (VEGF; P<0.05) and the upregulation of metastasis suppressor genes NM23 and E-cadherin (P<0.05). Taken together, the results of the present study demonstrated that the silencing of NSE suppressed the migration, proliferation and colony formation ability of SCLC cells and decreased the S-phase population. In addition, the knockdown of NSE resulted in the upregulation of E-cadherin and NM23 and the downregulation of VEGF. Collectively, these results indicated that intracellular NSE may have an important role in the progression of SCLC.

Novel role of semaphorin 3A in the growth and progression of hepatocellular carcinoma

Semaphorin 3A (SEMA3A), a secretory protein, is a founding member of the semaphorin family and functions in both the biological behavior of tumor cells and the modulation of tumor-associated macrophages. However, the role of SEMA3A in hepatocellular carcinoma (HCC) is still not well established. In the present study, we investigated the expression levels of SEMA3A in 80 HCC tissues and cell lines, using RT-qPCR, western blotting and immunohistochemistry. Expression profile analysis revealed that SEMA3A was significantly overexpressed in human HCC patients and positively correlated with the metastatic potential of HCC cells. Lentiviral transfection into PLC/PRF/5 and HCCLM3 cells was performed to stably upregulate and downregulate the expression of SEMA3A in HCC cells. Cell Counting Kit-8 (CCK-8), wound-healing and invasion assays revealed that SEMA3A promoted the proliferation and migration of HCC cells in vitro. Proteome profiler antibody microarray analysis revealed that overexpression of SEMA3A in HCC cells induced a significant increase in the expression levels of gelsolin-like capping protein (CapG), galectin-3, enolase 2 and epithelial cell adhesion molecule (EpCAM). Furthermore, the upregulation of SEMA3A in HCC cells promoted tumor growth and progression in an HCC mouse model. These results indicate that SEMA3A enhances CapG, galectin-3, enolase 2 and EpCAM expression to promote HCC progression and is a potential therapeutic target for HCC.