A modified in-gel DNA renaturation technique, which detects DNA sequences amplified greater than 7-fold in human DNA, was used to analyze gene amplification in surgical specimens of primary and metastatic ovarian carcinomas. Amplified DNA sequences were detected in two of eight tumors. Hybridization of these samples with different oncogene probes revealed that both tumors contained an amplified...

Mutations of the Ki-ras oncogene in endometrial carcinoma have been reported in Japan, but the prevalence and clinical significance of such mutations in the United States remains unclear. DNA extracted from paraffin sections of 112 carcinomas of the endometrium was amplified by the polymerase chain reaction with mismatched primers that generated a BstNI recognition site with the wild-type codon...

BACKGROUND Conditional transgenic models have established that tumors require sustained oncogene activation for tumor maintenance, exhibiting the phenomenon known as "oncogene-addiction." However, most cancers are caused by multiple genetic events making it difficult to determine which oncogenes or combination of oncogenes will be the most effective targets for their treatment. METHODOLOGY/PR...

colorectal cancer (crc) is one of the most common cancers worldwide. understanding of the tumor behavior, in a much closer look, at the molecular level, results in a more effective treatment and accurate prognosis of the disease. from among various genes altered in colorectal cancer k-ras is assumed to be of diagnostic and prognostic significance. k-ras mutations are believed to be a critical e...

Activation of K-ras oncogene has been implicated in colorectal carcinogenesis, being mutated in 30-60% of the adenocarcinomas. In this study, 737 incident colorectal cancer (CRC) patients, originating from 120 852 men and women (55-69 years at baseline) participating in the Netherlands Cohort Study (NLCS), were studied in order to evaluate subgroups with respect to K-ras mutation status. Mutati...

Transfection of primary rat embryo fibroblasts with the H-ras oncogene plus the cooperating oncogene v-myc results in the development of foci of morphologically altered tumorigenic cells. We examined radiation (X-rays) induced inhibition of DNA synthesis in cell lines derived from such transformed clones and compared the results to those obtained with the nontransformed parental cells, rat embr...

Abstract :  Reovirus (respiratory enteric orphan virus), a naturally occurring benign human pathogen, has an inherent ability to target transformed and cancerous cells and cause their lysis, while leaving non-transformed cells relatively unaffected.  The efficiency of this innate oncolytic activity of reovirus correlates with expression of the ras oncogene.  Cells expressing ac...

The effect of transfection of NIH 3T3 cells by the human ras (c-Ha-ras-1) oncogene on uptake, interconversion, and excretion of polyamines was studied. Uptake and interconversion of spermidine were higher in the ras-transfected cells. Acetylpolyamines were excreted into the medium by the ras-transfected cells, whereas they were retained by NIH 3T3 cells. In addition to acetylpolyamines, some un...

knowledge about the clinical significance of v-raf murine sarcoma viral oncogene homolog b1 ( braf ) mutations in colorectal cancer (crc) is growing. braf encodes a protein kinase involved with intracellular signaling and cell division. the gene product is a downstream effector of kirsten ras 1( kras ) within the ras/raf/mapk cellular signaling pathway. evidence suggests that braf mutations, li...