Solamargine (SM), isolated from Solanum incanum herb, displayed a superior cytotoxicity in four human lung cancer cell lines. The half-inhibitory concentrations (IC 50 ), of the cell viability assay for H441, H520, H661 and H69 cells were 3, 6.7, 7.2 and 5.8 lM, respectively. SM-induced apoptosis of these cells by PS externalization in a dose-dependent manner and increased sub-G 1 fraction were observed. Quenching of the expression of tumor necrosis factor receptors (TNFRs) during the progress of human lung carcinogenesis has been previously reported. SM may induce cell apoptosis via modulating the expression of TNFRs and their subsequent TRADD/FADD signal cascades. Subsequently, SM treatment increased the binding activities of TNF-a and TNF-b to the lung cancers, and the intrinsic TNFs-resistant cancer cells became susceptible to TNF-a and -b. In addition, SM caused release of cytochrome c, downregulation of anti-apoptotic Bcl-2 and Bcl-x L , increase of caspase-3 activity, and DNA fragmentation. Thus, SM could modulate the expressions of TNFRs and Bcl-2, and might be a potential anticancer agent for TNFs and Bcl-2 related resistance of human lung cancer cells.

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BackgroundNasopharyngeal carcinoma (NPC) is known for its high metastatic potential and locoregional recurrence, although the molecular alterations that are driving NPC metastasis remain unclear at this time. This study aimed to examine the expression of fibulin-5 in NPC, correlate the results with clinicopathological variables and survival, and to investigate the role of fibulin-5 in human NPC cell lines.Material and MethodsStandard semi-quantitative-RT-PCR, quantitative-RT-PCR, immunoblotting, and immunohistochemistry were used to investigate the mRNA and protein expression profiles of fibulin-5 in normal and NPC tissues. Immunohistochemistry of fibulin-5 was correlated with clinicopathological characteristics by univariate analyses. NPC cells overexpressing fibulin-5 or fibulin-5-siRNA cells were generated by stable transfection to characterize the molecular mechanisms of fibulin-5-elicited cell growth and metastasis.ResultsOur results demonstrated that fibulin-5 overexpression in NPC specimens and significantly correlated with advanced tumor metastasis indicating a poor 5-year overall survival. Fibulin-5 was mainly expressed in the nucleus in human NPC specimens and cell lines. Functionally, fibulin-5 overexpression yielded fast growth in NPC cells. In addition, fibulin-5 promotes cell metastasis in NPC cells through increased FLJ10540 and phosphor-AKT activity. In contrast, siRNA depletion of fibulin-5 suppressed FLJ10540 expression and phosphor-AKT activity. Suppression of either fibulin-5 or FLJ10540 can cause significant inhibition with regards to cell motility in NPC cells. Finally, immunohistochemical analysis of human aggressive NPC specimens showed a significant and positive correlation between fibulin-5 and FLJ10540 expression.ConclusionHigher fibulin-5 expression is not only an important indicator of poor survival, but also contributes to the development of new therapeutic strategies in the FLJ10540/AKT pathway for NPC treatment.

The functions of Rap-1A in oral carcinogenesis are largely unexplored. In this study, we examined the expression of Rap-1A at different malignant stages of oral cavity squamous cell carcinoma (OCSCC). Semiquantitative RT-PCR, quantitative RT-PCR, and Western blotting were used to evaluate Rap-1A mRNA and protein expressions, respectively, in paired OCSCC patient specimens. To determine the possible correlation between Rap-1A expression and various clinical characteristics, 256 samples from patients with OCSCC were evaluated by immunohistochemical staining. Strong Rap-1A expression was a significant prognostic marker and predictor of aggressive OCSCC. The overall and disease-specific 5-year survival rates were significantly correlated with strong expression of Rap-1A (P < 0.001). Functionally, overexpressed Rap-1A could promote oral cancer cell migration and invasion by Transwell chambers and wound healing assay. Conversely, the suppression of Rap-1A expression using Rap-1A-mediated siRNA was sufficient to decrease cell motility. Furthermore, our data also illustrated that Aurora-A could not only induce mRNA and protein expressions of Rap-1A for enhancing cancer cell motility but also co-localize and form a complex with Rap-1A in the oral cancer cell line. Finally, immunohistochemical staining, indirect immunofluorescence, and Western blotting analysis of human aggressive OCSCC specimens revealed a significantly positive correlation between Rap-1A and Aurora-A expression. Taken together, our results suggest that the Aurora-A/Rap-1A pathway is associated with survival, tumor progression, and metastasis of OCSCC patients.

The proliferation and migration of hepatic stellate cells (HSCs) profoundly impact the pathogenesis of liver inflammation and fibrogenesis. As a perennial herb native to China, Bupleurum falcatum is administered for its anti-inflammatory, antipyretic, and antihepatotoxic effects. Saikosaponin a (SSa) and Saikosaponin d (SSd) are the major active components of triterpene saponins in Bupleurum falcatum. This study analyzes how SSa and SSd affect rat HSC-T6 cell line proliferation and migration. Experimental results indicate that, in addition to suppressing HSC-T6 proliferation, wound healing activity and cell migration in a time-and dose-dependent manner, SSa and SSd significantly induce apoptosis. Additionally, SSa and SSd decreased the expressions of extracellular matrix-regulated kinase 1/2 (ERK1/2), platelet-derived growth factor receptor 1 (PDGFR1), and subsequently transforming growth factor-b1 receptor (TGF-b1R), a-smooth muscle actin, TGF-b1 and connective tissue growth factor. They also decreased phosphorylation of p38 (p-p38) and ERK1/2 (p-ERK1/2) of HSC-T6. Furthermore, both SSa and SSd can block PDGF-BB and TGF-b1-induced cell proliferation and migration of HSC-T6. These results suggest that SSa and SSd may inhibit proliferation and activation of HSC-T6, and the modulated mechanisms warrant further study.