The gene encoding the Ras-related GTPase RhoB-specific is immediate-early inducible by genotoxic treatments. Regulation of transcriptional activation of rhoB is still unclear. Here we show that cells lacking either p53 or c-Fos are not different from wild-type cells with respect to the level of rhoB induction upon UV irradiation, indicating that these transcription factors are not crucial for s...

BACKGROUND RhoB is a member of the Rho small GTPase family that regulates cytoskeletal dynamics and vesicle trafficking. The RhoB homologs, RhoA and RhoC, have been shown to promote cancer progression and metastasis. In contrast, the functions of RhoB in human cancers are context dependent. Although expression of RhoB inversely correlates with disease progression in several epithelial cancers, ...

Although recent evidence supports a tumor-suppressive role for the GTPase RhoB, little is known about its regulation by signal transduction pathways. Here we demonstrate that Ras downregulates RhoB expression by a phosphatidylinositol 3-kinase (PI3K)- and Akt- but not Mek-dependent mechanism. Furthermore, genetic and pharmacological blockade of PI3K/Akt results in upregulation of RhoB expressio...

PURPOSE RhoB is a low molecular weight GTPase belonging to the Ras protein superfamily. Whereas most Rho proteins have been shown to have a positive role in proliferation and malignant transformation, the specific role of RhoB appears more divergent. We reported previously that RhoB inhibits cell proliferation in various human cancer cells. Here, we studied the specific role played by RhoB in h...

The Rho family of small GTPases play a pivotal role in the dynamic regulation of the actin cytoskeleton. Recent studies have suggested that these signalling proteins also have wide-ranging functions in membrane trafficking pathways. The Rho family member RhoB was shown to localise to vesicles of the endocytic compartment, suggesting a potential function in regulation of endocytic traffic. In ke...

PURPOSE A crucial event in lung adenocarcinoma progression is the switch from an aerogenous spread toward an infiltrating tumor. Loss of RhoB expression has been suggested to be critical for lung cancer invasion. Here, we tested RhoB expression as a prognostic biomarker in non-small cell lung cancer (NSCLC) with a special focus on lepidic pattern. EXPERIMENTAL DESIGN We analyzed RhoB expressi...

We demonstrated that the RhoB signaling pathway, regulates ACh release via actin cytoskeletal reorganization and that botulinum toxin type A (BoNT) inhibits neuroexocytosis by targeting the RhoB pathway in nerve growth factor-differentiated PC12 cells. To confirm these facts, small interfering RNA (siRNA) was used to knockout the expression of RhoB. Transfection of PC12 cells by the siRNA resul...

Anabolic activity, phenotypic alterations, and in particular survival of the chondrocytes are essential for the maintenance of proper articular cartilage and appears to fail during osteoarthritic cartilage degeneration. In this study, we investigated the presence and expression of RhoB in adult human articular cartilage and its regulation in osteoarthritic cartilage as well as in chondrocytes i...