Vimentin expression and the influence of Matrigel in cell lines of head and neck squamous cell carcinoma

Vimentin is a cytoeskeletal intermediate filament protein commonly observed in mesenchymal cells; however, it can also be found in malignant epithelial cells. It is demonstrated in several carcinomas, such as those of the cervix, breast and bladder, in which it is widely used as a marker of the epithelial to mesenchymal transition that takes place during embryogenesis and metastasis. Vimentin is associated with tumors that show a high degree of invasiveness, being detected in invasion front cells. Its expression seems to be influenced by the tumor microenvironment. The aim of this study was to evaluate vimentin expression in head and neck squamous cell carcinoma (HNSCC) cell lines, and to investigate the contribution of the microenvironment to its expression. HNSCC cell lines (HN6, HN30 and HN31) and an immortalized nontumorigenic cell line (HaCaT) were submitted to a three-dimensional assay with Matrigel. Cytoplasmatic staining of the HN6 cell line cultured without Matrigel and of the HN30 and HN31 cell lines cultured with Matrigel was demonstrated through immunohistochemistry. Western Blotting revealed a significant decrease in vimentin expression for the HN6 cell line and a significant increase for the HN30 and HN31 cell lines cultured with Matrigel. The results suggest that vimentin can be expressed in HNSCC cells and its presence is influenced by the microenvironment of a tumor.

A semi-quantitative assay to screen for angiogenic compounds and compounds with angiogenic potential using the EA. hy926 endothelial cell line

Angiogenesis, the development of new capillary vessels, has a host of clinical manifestations. The identification of agents that increase or decrease angiogenesis is of great pharmaceutical interest. Classically, in vitro angiogenesis utilizes human umbilical vein endothelial cells (HUVEC) grown in matrigel. This valid and simple method has the drawbacks that each cell population is distinct and the constraint of obtaining primary source material. Herein we utilize the established EA.hy926 endothelial cell line as our model for in vitro angiogenesis and present a novel formula to quantify endothelial cell remodeling to identify pro- and anti-angiogenic agents. Furthermore, our technique details the procedures to identify and quantify compounds that have the capacity to generate pro- or anti-angiogenic factors when given to non-endothelial cells, which we define herein as angiogenic potential. In conclusion, we propose a novel formula that we are confident accurately reflects the degree of in vitro angiogenesis allowing the quantification of prospective angiogenic compounds.

Efecto de los proteoglicanos arteriales sobre la oxidación in vitro de LDL aislada de pacientes hipercolesterolémicos / Effect of arterial proteoglycans on in vitro oxidation of LDL isolated from hypercholesterolemic patients

The interaction of LDL with extracellular matrix proteoglycan apparently contribute to the acumulation of apo B-lipoproteins in atherogenesis. Retention of LDL by intima proteoglycans appears to increase the residence time needed for their structural, hydrolytic and oxidative modification. If the rate of LDL entry exceeds the tissue capacity to eliminate the modified products, this process may contribute to atherogenesis. In this study we explored whether alterations of LDL induced by human arterial CSPG alter the lipoprotein susceptibility to copper-catalyzed oxidation. Human LDL was complexed with human arterial CSPG and dissociated by raising the ionic strength. The CSPG-treated LDL was subjected to oxidation by micromolar amounts of copper. This treatment increased LDL susceptibility to oxidation 8 times, as indicated by formation rates of thiobarbituric acid-reacting substances (TBARS). Furthermore, the hypercholesterolemic patients show LDL with significantly higher affinity for arterial proteoglycans than LDL from controls.

Actividad biológica de biopolimeros de origen marino; I: influencia sobre la actividad asesina natural (NK) en el ratón / Biologic activity of biopolymers of marine origen; I: influence on natural killer cell (NK) activity in the mouse

El papel de las células asesinas naturales (NK) en la respuesta antitumoral y en la respuesta antimetastizante del organismo ha sido ampliamente evaluada. Es por eso que en nuestro estudio analizamos el efecto de 3 biopolímeros de origen natural (marino) producidos en nuestro instituto sobre este elemento de la inmunidad no específico. En nuestro trabajo experimental observamos que los productos 22CM062 y 22M016 resultaron ser notables activadores de la función de este tipo de células mientras el producto 22V117 se mostró inefectivo

Actividad biológica de biopolímeros de origen marino; II: influencia sobre la actividad de macrófagos peritoneales de ratón / Biologic activity of biopolymers of marine origin; II: influence on the activity of mouse peritoneal macrophages

Es altamente conocido el papel que desempeñan los macrófagos en el proceso de inhibición de la metastización. En el presente trabajo reportamos los resultados obtenidos al evaluar 3 biopolímeros de origen marino producidos en nuestro instituto sobre dos funciones características de estas células. Nosotros encontramos que los productos 22CM062 y 22V117 estimularon notablemente la actividad quimioluminiscente y citostática de estas células, mientras que el producto 22M016 produjo un efecto poco notable.