The human ras gene plays a fundamental role in the transduction of extracellular signals to the nucleus, thereby regulating cell growth and differentiation. Point mutations in the ras gene convert it into a transforming oncogene that has been found in many solid and hematologic malignancies. We describe a rapid and sensitive assay based on a radiolabeled polymerase chain reaction followed by re...

We assessed the role of the cell labile iron pool in mediating oncogene-induced cell proliferation via repression of ferritin expression. When HEK-293 cells, engineered to inducibly express either active (+) or dominant-negative (-) forms of the H-ras oncogene, were treated with antisense nucleotides to ferritin subunits they displayed (a) decreased ferritin levels, (b) increased labile iron po...

background: endometrial cancer is the most common gynecologic malignancy that has often proceeded by a premalignant phase. modern molecular and immune staining methods for precancerous lesions diagnosis have been expanded. one of the genetic alternations in the endometrial cancer carcinogenesis is the mutational activation of the k-ras oncogene. k-ras mutation has recognized to occur at an earl...

The isoprenoid pathway in FRTL-5 thyroid cells was found to be deeply altered on transformation with v-K-ras. A dramatic overall reduction of protein prenylation was found in v-K-ras-transformed cells in comparison with the parent FRTL-5 cells, as shown by labeling cells with [3H]mevalonic acid. This phenomenon was accompanied by a relative increase of p21(ras) farnesylation and by a decrease o...

HYPOTHESIS Are different events involved in the development of sporadic versus hereditary tumours? The possible importance of the microenvironment in hereditary cancer In a recent review, Weinberg (1989) has discussed apparent violations of multistep carcinogenesis when in some cases full transformation of primary cultures by single oncogenes (ras) has been reported. Normally at least two coope...

The STP-C488 oncogene of herpesvirus saimiri has transforming activity independent of the rest of the viral genome. We now demonstrate that STP-C488 associates with cellular ras in transformed cells. Mutations that disrupted this association with ras disrupted the transforming ability of the STP-C488 oncogene. Binding assays showed that STP-C488 was capable of competing with raf-1 for binding t...

of introducing a mutant ras oncogene into cells. In the Whitehead Institute for Biomedical Research 1970s, the effects elicited by a ras oncogene were Department of Biology Massachusetts Institute thought obvious: ostensibly normal cells exposed to of Technology this gene would become transformed into cancer cells. Cambridge, Massachusetts 02142 Then, in 1983, the beginnings of subtlety became ...

Nuclear microinjection of c-H-ras DNA induced DNA synthesis in reversibly nonproliferating quiescent human cells. The proto-oncogene and oncogene forms were equally effective inducers. In contrast, c-H-ras DNA either alone or in combination with the adenovirus E1A gene did not cause terminally nondividing senescent cells to synthesize DNA.

Pancreatic ductal adenocarcinoma is one of the most aggressive malignancies, characterized by the local invasion into surrounding tissues and early metastasis to distant organs. Oncogenic mutations of the K-RAS gene occur in more than 90% of human pancreatic cancers. The goal of this study was to investigate the functional significance and downstream effectors of mutant K-RAS oncogene in the pa...

Both Myc and Ras oncogenes impact cellular metabolism, deregulate redox homeostasis and trigger DNA replication stress (RS) that compromises genomic integrity. However, how are such oncogene-induced effects evoked and temporally related, to what extent are these kinetic parameters shared by Myc and Ras, and how are these cellular changes linked with oncogene-induced cellular senescence in diffe...