The γ-Benzylidene Digoxin Derivative BD-15 Increases the α3-Na, K-ATPase Activity in Rat Hippocampus and Prefrontal Cortex and no Change on Heart.

Our study aimed to investigate the effects of the new cardiotonic steroid BD-15 (γ-benzylidene derivatives) in the behavioral parameters, oxidative stress and the Na, K-ATPase activity in the hippocampus, prefrontal cortex and heart from rats to verify the safety and possible utilization in brain disorders. For this study, groups of male Wistar rats were used after intraperitoneal injection of 20, 100 and 200 µg/Kg with BD-15. The groups were treated for three consecutive days and the control group received 0.9% saline. BD-15 did not alter behavior of rats treated with different doses. An increase in the specific α2,3-Na, K-ATPase activity was observed for all doses of BD-15 tested in the hippocampus. However, in the prefrontal cortex, only the dose of 100 µg/Kg increased the activity of all Na, K-ATPase isoforms. BD-15 did not cause alteration in the lipid peroxidation levels in the hippocampus, but in the prefrontal cortex, a decrease of lipid peroxidation (~ 25%) was observed. In the hippocampus, GSH levels increased with all doses tested, while in the prefrontal cortex no changes were found. Subsequently, when the effect of BD-15 on cardiac tissue was analyzed, no changes were observed in the tested parameters. BD-15 at a dosage of 100 µg/Kg proved to be promising because it is considered therapeutic for brain disorders, since it increases the activity of the α3-Na, K-ATPase in the hippocampus and prefrontal cortex, as well as decreasing the oxidative stress in these brain regions. In addition, this drug did not cause changes in the tissues of the heart and kidneys, preferentially demonstrating specificity for the brain.

TNF-alpha and melphalan modulate a specific group of early expressed genes in a murine melanoma model.

BACKGROUND: Cutaneous melanoma displays high morbidity and mortality rates. Isolated limb perfusion with melphalan (Mel) is used for the treatment of non-resectable, locally advanced extremity melanomas. When combined with tumor necrosis factor alpha (TNF-alpha) treatment, the complete response varies between 70% and 90%. The mechanisms underlying the effects of Mel and TNF-alpha are not completely understood. We evaluated the impact of systemic Mel and TNF-alpha administration on tumor growth, analyzed the morphological changes promoted by each treatment, and identified early expressed genes in response to Mel and TNF-alpha treatment, either alone or in combination, in a murine melanoma model. METHODS: Six- to eight-week-old male mice were subcutaneously inoculated with B16F10 melanoma cells and then intravenously injected with TNF-alpha, melphalan or a combination of both drugs when the tumors reached 1.0 cm(2). Tumor growth was monitored every other day, and histological analysis was performed when the tumors reached 3.0 cm(2). Total RNA was extracted from the resected tumors and submitted to amplification, labeling and hybridization on an oligonucleotide microarray (Fox Chase Cancer Center). Tumor growth and histological parameters were compared using ANOVA. Survival curves were calculated using the Kaplan-Meier method. Two-way ANOVA was used to identify differentially expressed genes among the various treatments, and Dunn's test was used for pair-wise comparisons. RESULTS: Systemic administration of Mel impaired tumor growth (p<0.001), improved animal survival (p<0.001), and decreased mitotic rate (p=0.049). Treatment with TNF-alpha alone had no impact, neither on tumor growth, nor on survival, but it increased necrosis (p<0.024) and decreased mitotic rates (p=0.001) in the tumors. Combined treatment with Mel and TNF-alpha had similar effects in tumor growth, survival, necrosis and mitotic rate as observed with individual treatments. Moreover, 118 genes were found differentially expressed by microarray analysis and 10% of them were validated by RT- real time PCR. In our model we found that the treatments regulate genes that play important roles in tumorigenesis such as cell adhesion (Pard3, Pecam1, Ilk, and Dlg5), proliferation (Tcfe3 and Polr1e), cell motility (Kifap3, Palld, and Arhgef6), apoptosis (Bcl2l11), and angiogenesis (Flt1 and Ptprj). CONCLUSIONS: Our data reproduces, in mice, some of the features observed in melanoma patients treated with the combination of Mel and TNF-alpha. The identification of genes with altered expression by these drugs both individually and in combination might help in the understanding of their mechanism of action and, as a consequence, improved strategies that could impact their clinical application.

Gene network analyses point to the importance of human tissue kallikreins in melanoma progression.

BACKGROUND: A wide variety of high-throughput microarray platforms have been used to identify molecular targets associated with biological and clinical tumor phenotypes by comparing samples representing distinct pathological states. METHODS: The gene expression profiles of human cutaneous melanomas were determined by cDNA microarray analysis. Next, a robust analysis to determine functional classifications and make predictions based on data-oriented hypotheses was performed. Relevant networks that may be implicated in melanoma progression were also considered. RESULTS: In this study we aimed to analyze coordinated gene expression changes to find molecular pathways involved in melanoma progression. To achieve this goal, ontologically-linked modules with coordinated expression changes in melanoma samples were identified. With this approach, we detected several gene networks related to different modules that were induced or repressed during melanoma progression. Among them we observed high coordinated expression levels of genes involved in a) cell communication (KRT4, VWF and COMP); b) epidermal development (KLK7, LAMA3 and EVPL); and c) functionally related to kallikreins (EVPL, KLK6, KLK7, KLK8, SERPINB13, SERPING1 and SLPI). Our data also indicated that hKLK7 protein expression was significantly associated with good prognosis and survival. CONCLUSIONS: Our findings, derived from a different type of analysis of microarray data, highlight the importance of analyzing coordinated gene expression to find molecular pathways involved in melanoma progression.

Identification of genes associated with local aggressiveness and metastatic behavior in soft tissue tumors.

Soft tissue tumors represent a group of neoplasia with different histologic and biological presentations varying from benign, locally confined to very aggressive and metastatic tumors. The molecular mechanisms responsible for such differences are still unknown. The understanding of these molecular alterations mechanism will be critical to discriminate patients who need systemic treatment from those that can be treated only locally and could also guide the development of new drugs' against this tumors. Using 102 tumor samples representing a large spectrum of these tumors, we performed expression profiling and defined differentially expression genes that are likely to be involved in tumors that are locally aggressive and in tumors with metastatic potential. We described a set of 12 genes (SNRPD3, MEGF9, SPTAN-1, AFAP1L2, ENDOD1, SERPIN5, ZWINTAS, TOP2A, UBE2C, ABCF1, MCM2, and ARL6IP5) showing opposite expression when these two conditions were compared. These genes are mainly related to cell-cell and cell-extracellular matrix interactions and cell proliferation and might represent helpful tools for a more precise classification and diagnosis as well as potential drug targets.

Expression profile of malignant and nonmalignant lesions of esophagus and stomach: differential activity of functional modules related to inflammation and lipid metabolism.

Adenocarcinomas of stomach and esophagus are frequently associated with preceding inflammatory alterations of the normal mucosa. Whereas intestinal metaplasia of the gastric mucosa is associated with higher risk of malignization, Barrett's disease is a risk factor for adenocarcinoma of the esophagus. Barrett's disease is characterized by the substitution of the squamous mucosa of the esophagus by a columnar tissue classified histopathologically as intestinal metaplasia. Using cDNA microarrays, we determined the expression profile of normal gastric and esophageal mucosa as well as intestinal metaplasia and adenocarcinomas from both organs. Data were explored to define functional alterations related to the transformation from squamous to columnar epithelium and the malignant transformation from intestinal metaplasia to adenocarcinomas. Based on their expression profile, adenocarcinomas of the esophagus showed stronger correlation with intestinal metaplasia of the stomach than with Barrett's mucosa. Second, we identified two functional modules, lipid metabolism and cytokine, as being altered with higher statistical significance. Whereas the lipid metabolism module is active in samples representing intestinal metaplasia and inactive in adenocarcinomas, the cytokine module is inactive in samples representing normal esophagus and esophagitis. Using the concept of relevance networks, we determined the changes in linear correlation of genes pertaining to these two functional modules. Exploitation of the data presented herein will help in the precise molecular characterization of adenocarcinoma from the distal esophagus, avoiding the topographical and descriptive classification that is currently adopted, and help with the proper management of patients with Barrett's disease.