RESUMEN
Increased levels of the calcium-binding protein neuronal calcium sensor 1 (NCS1) predict an unfavorable patient outcome in several aggressive cancers, including breast and liver tumors. Previous studies suggest that NCS1 overexpression facilitates metastatic spread of these cancers. To investigate this hypothesis, we explored the effects of NCS1 overexpression on cell proliferation, survival, and migration patterns in vitro in 2- and 3-dimensional (2/3-D). Furthermore, we translated our results into an in vivo mouse xenograft model. Cell-based proliferation assays were used to demonstrate the effects of overexpression of NCS1 on growth rates. In vitro colony formation and wound healing experiments were performed and 3-D migration dynamics were studied using collagen gels. Nude mice were injected with breast cancer cells to monitor NCS1-dependent metastasis formation over time. We observed that increased NCS1 levels do not change cellular growth rates, but do significantly increase 2- and 3-D migration dynamics in vitro. Likewise, NCS1-overexpressing cells have an increased capacity to form distant metastases and demonstrate better survival and less necrosis in vivo. We found that NCS1 preferentially localizes to the leading edge of cells and overexpression increases the motility of cancer cells. Furthermore, this phenotype is correlated with an increased number of metastases in a xenograft model. These results lay the foundation for exploring the relevance of an NCS1-mediated pathway as a metastatic biomarker and as a target for pharmacologic interventions.-Apasu, J. E., Schuette, D., LaRanger, R., Steinle, J. A., Nguyen, L. D., Grosshans, H. K., Zhang, M., Cai, W. L., Yan, Q., Robert, M. E., Mak, M., Ehrlich, B. E. Neuronal calcium sensor 1 (NCS1) promotes motility and metastatic spread of breast cancer cells in vitro and in vivo.
Asunto(s)
Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Proteínas Sensoras del Calcio Neuronal/metabolismo , Neuropéptidos/metabolismo , Animales , Línea Celular Tumoral , Proliferación Celular/genética , Proliferación Celular/fisiología , Femenino , Humanos , Ratones , Ratones Desnudos , Microscopía Fluorescente , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Background: Hepatocellular carcinoma (HCC) is the second leading cause of cancer-related death worldwide. There is an urgent demand for prognostic biomarkers that facilitate early tumor detection, as the incidence of HCC has tripled in the United States in the last three decades. Biomarkers to identify populations at risk would have significant impact on survival. We recently found that expression of Neuronal Calcium Sensor 1 (NCS1), a Ca2+-dependent signaling molecule, predicted disease outcome in breast cancer, but its predictive value in other cancer types is unknown. This protein is potentially useful because increased NCS1 regulates Ca2+ signaling and increased Ca2+ signaling is a hallmark of metastatic cancers, conferring cellular motility and an increasingly aggressive phenotype to tumors.Methods: We explored the relationship between NCS1 expression levels and patient survival in two publicly available liver cancer cohorts and a tumor microarray using data mining strategies.Results: High NCS1 expression levels are significantly associated with worse disease outcome in Asian patients within these cohorts. In addition, a variety of Ca2+-dependent and tumor growth-promoting genes are transcriptionally coregulated with NCS1 and many of them are involved in cytoskeleton organization, suggesting that NCS1 induced dysregulated Ca2+ signaling facilitates cellular motility and metastasis.Conclusions: We found NCS1 to be a novel biomarker in HCC. Furthermore, our study identified a pharmacologically targetable signaling complex that can influence tumor progression in HCC.Impact: These results lay the foundation for using NCS1 as a prognostic biomarker in prospective cohorts of HCC patients and for further functional assessment of the characterized signaling axis. Cancer Epidemiol Biomarkers Prev; 27(9); 1091-100. ©2018 AACR.
Asunto(s)
Calcio/metabolismo , Carcinoma Hepatocelular/mortalidad , Neoplasias Hepáticas/mortalidad , Proteínas Sensoras del Calcio Neuronal/metabolismo , Neuropéptidos/metabolismo , Biomarcadores de Tumor , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/terapia , Estudios de Cohortes , Terapia Combinada , Femenino , Estudios de Seguimiento , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/terapia , Masculino , Pronóstico , Tasa de SupervivenciaRESUMEN
We used ultrafast x radiography and developed a novel multiphase numerical simulation to reveal the origin and the unique dynamics of the liquid-jet-generated shock waves and their interactions with the jets. Liquid-jet-generated shock waves are transiently correlated to the structural evolution of the disintegrating jets. The multiphase simulation revealed that the aerodynamic interaction between the liquid jet and the shock waves results in an intriguing ambient gas distribution in the vicinity of the shock front, as validated by the ultrafast x-radiography measurements. The excellent agreement between the data and the simulation suggests the combined experimental and computational approach should find broader applications in predicting and understanding dynamics of highly transient multiphase flows.
Asunto(s)
Ondas de Choque de Alta Energía , Modelos Teóricos , Radiografía/métodos , Simulación por Computador , Aceite Mineral/química , Hexafluoruro de Azufre/química , Rayos XRESUMEN
Phospholipid-ethanol-aqueous mixtures containing bilayer-forming lipids and 20-50 wt.% of water form viscous gels. Further hydration of these gels results in the formation of liposomes whose morphology depends upon the lipid type. Upon hydration of gels containing mixtures of the lipids 1-palmitoyl-2-oleoyl-phosphatidylcholine (POPC) and 1-palmitoyl-2-oleoyl-phosphatidylglycerol (POPG), small homogeneous and unilamellar liposomes were produced. In contrast, hydration of gels containing only POPC resulted in formation of large multilamellar liposomes. Likewise, mulitlamellar liposomes resulted when this method was applied to form highly fusogenic liposomes comprised of the novel negatively charged N-acyl-phosphatidylethanolamine (NAPE) mixed with di-oleoyl-phosphatidylcholine (DOPC) (7:3) [T. Shangguan, C.C. Pak, S. Ali, A.S. Janoff, P. Meers, Cation-dependent fusogenicity of an N-acyl phosphatidylethanolamine, Biochim. Biophys. Acta 1368 (1998) 171-183]. In all cases, the measured aqueous entrapment efficiencies were relatively high. To better understand how the molecular organization of these various gels affects liposome morphology, we examined samples by freeze-fracture transmission electron microscopy and X-ray diffraction. We found that phospholipid-ethanol-water gels are comprised of highly organized stacks of lamellae. A distinct feature of the gel samples that result in small unilamellar liposomes is the combination of acyl chain interdigitation and net electrostatic charge. We speculate that the mechanism of unilamellar liposome formation proceeds via formation of stalk contacts between neighboring layers similar to membrane hemifusion intermediates, and the high aqueous entrapment efficiencies make this liposome formation process attractive for use in drug delivery applications.