The human lbc oncogene product is a guanine nucleotide exchange factor that specifically activates the Rho small GTP binding protein, thus resulting in biologically active, GTP-bound Rho, which in turn mediates actin cytoskeletal reorganization, gene transcription, and entry into the mitotic S phase. In order to elucidate the mechanism of onco-Lbc transformation, here we report that while proto...

Transformation of fibroblast cells by v-abl oncogene involved overexpression of the c-myc (5) or of the cellular protein p53 (6). Two proto-oncogenes, cmyc and c-K-ras, have been shown to cooperate in the transformation of secondary rat embryo fibroblasts (7). Oncogenic activation of c-myc occurs mainly through constituve and elevated expression of its gene product and generally requires cooper...

background:breast cancer remains the most common and second lethal cancer in females. her-2/neu is one of the most important amplified oncogene in breast cancer. the amplification of her-2 is correlated with decreased survival, metastasis, and early recurrence.  the amplification of her-2/neu gene and synthesis of the protein are reported in 10%-34% of breast cancer cases associated with tumor ...

The c-kit proto-oncogene encodes a receptor tyrosine kinase that is thought to play an important role in hematopoiesis. In a series of human acute myeloblastic leukemia (AML), the expression of the c-kit proto-oncogene and its product was studied by means of Northern blot and immunoblot analyses. The c-kit mRNA was expressed in 20 of 25 cases of AML, and in those cases the product of the c-kit ...

BACKGROUND Proto-oncogene c-erbB-2 is located in chromosome 17 region q21 and codifies a 185 Kd protein, with tyrosine kinase activity. The amplification of this gene is associated with relapse and lower survival in breast cancer. Overexpression of this gene can be detected by immunohistochemistry (IHC). However, fluorescence in situ hybridization (FISH) and chromogenic in situ hybridization (C...

Asbestos fibers cause persistent increases in activator protein-1 (AP-1) family member proto-oncogenes in lung epithelial and mesothelial cells that are linked to proliferation and cell transformation. Using lung epithelial cells, the progenitor cells of lung cancers, we report that crocidolite asbestos initially depletes intracellular glutathione followed by up-regulation of both catalytic and...

Proto-oncogene fos mRNA levels are rapidly and transiently elevated 12-fold in regenerating liver 10-60 min following partial hepatectomy. This response, and the induction of fos protein synthesis, has been simulated qualitatively and quantitatively in long term primary cultures of quiescent adult rat hepatocytes where proliferative transitions can be initiated directly in serum-free medium by ...

introduction: gastric cancer remains the second most common cause of cancer-related deaths worldwide. in many malignancies like, lung and breast, multiple prognostic factors are known, such as mutations in ki-67, her-2/neu, p53. in this study, we evaluated immunohistochemical protein expression patterns of cell-cycle-regulators p53, proliferation marker ki-67, surface expression of cd44, her-2/...

Rep68 protein, encoded by adeno-associated virus type 2 (AAV), has been previously shown to bind to specific sequences within the viral genome and in human chromosome 19. The effect of AAV Rep protein on human cellular genes is of interest because AAV is being developed as a gene therapy vector. We have identified sequences related to the Rep recognition sequence in the AAV P5 promoter in or ne...

Unfertilized frog eggs arrest at the second meiotic metaphase, due to cytostatic activity of the c-mos proto-oncogene (CSF). MAP kinase has been proposed to mediate CSF activity in suppressing cyclin degradation. Using an in vitro assay to generate CSF activity, and recombinant CL 100 phosphatase to inactivate MAP kinase, we confirm that the c-mos proto-oncogene blocks cyclin degradation throug...