background : â  celiac disease (cd) is an immune-mediated inflammation of the small intestine caused by sensitivity to dietary gluten and related proteins in genetically sensitive individuals . recurrent aphthous stomatitis (ras) is an inflammatory condition characterized by painful recurrent, single or multiple ulcerations of the oral mucosa. the association between cd and ras has been evaluat...

Recently, several groups have reported that Ras association domain family 1 (RASSF1A) interacts with Ras and mediates Ras-dependent apoptosis. However, the mechanism by which RASSF1A plays a role as a tumor suppressor in human cancer is unclear. In this study, we investigated the relationship between the RASSF1A methylation and K-ras mutation and their effects on patient's survival in 242 prima...

In the majority of breast cancers, overexpression and hyperactivation of Ras in the tumor microenvironment play significant role in promoting cancer cell growth, angiogenesis, and metastasis. We have previously shown that vascular endothelial growth factor (VEGF) expression in triple negative breast cancer cells is regulated, at least in part, by SAF-1 (serum amyloid A activating factor 1) tran...

PURPOSE While the dysregulation of specific pathways in cancer influences both treatment response and outcome, few current prognostic markers explicitly consider differential pathway activation. Here we explore this concept, focusing on K-Ras mutations in lung adenocarcinoma (present in 25%-35% of patients). EXPERIMENTAL DESIGN The effect of K-Ras mutation status on prognostic accuracy of exi...

The induction of tumors with chemicals and the production of transgenic animals are two experimental approaches to study oncogene involvement in carcinogenesis. The combination of both strategies offers an excellent model system to study tumor development. This study analyzes the potential cooperation of N-methylnitrosourea (MNU) treatment and N-ras proto-oncogene overexpression in tumorigenesi...

Mammalian Ras, which is encoded by three independent genes, has been thought to be a versatile component of intracellular signalling. However, when, where and how Ras signalling plays essential roles in development and whether the three Ras genes have overlapping functions in particular cells remain unclear. Here, we show that the three Ras proteins dose-dependently regulate lymphatic vessel gr...

Oncogenic K-Ras mutation occurs frequently in several types of cancers, including pancreatic and lung cancers. Tumors with K-Ras mutation are resistant to chemotherapeutic drugs as well as molecular targeting agents. Although numerous approaches are ongoing to find effective ways to treat these tumors, there are still no effective therapies for K-Ras mutant cancer patients. Here we report that ...

Organ-specific cancers with activated ras oncogenes most often are associated exclusively with only one ras isoform. For example, only H-ras activation is associated with rat mammary cancers. The mechanism underlying this specificity is mostly unknown. We have shown previously that this tissue specificity of Ras isoforms is defined by the Ras protein itself and not by differential gene expressi...

RAS genes are among the most frequently mutated proto-oncogenes in cancer. However, how Ras stability is regulated remains largely unknown. Here, we report a regulatory loop involving the E3 ligase Nedd4-1, Ras, and PTEN. We found that Ras signaling stimulates the expression of Nedd4-1, which in turn acts as an E3 ubiquitin ligase that regulates Ras levels. Importantly, Ras activation, either b...

ras proto-oncogenes have traditionally been associated with the regulation and promotion of cell growth. We have induced thymic lymphomas in N-ras(-/-) mice and in transgenic mice that overexpress wild-type N-ras and found that the lack of wild-type N-ras alleles favors the development of thymic lymphomas,whereas overexpression of wild-type N-ras protects against thymic lymphomagenesis in the p...