RAS mutations arise at high frequency in human malignancy and have been shown to play a role in the disruption of both normal differentiation and proliferation. In addition, RAS influences a number of intracellular signaling pathways, which impinge on proteins that regulate programmed cell death. In this study, we have examined whether this oncogene can influence the activation of the apoptotic...

The oncogene N-ras has been found to be amplified (congruent to 20 copies) in the human breast carcinoma cell line MCF-7. The amplified sequences have been localized to a marker chromosome by in situ hybridization. Sublines of MCF-7, serially passaged in different laboratories, have marked variation in the degree of N-ras amplification. The differing degrees of amplification of N-ras are furthe...

RAS mutations arise at high frequency in human malignancy and have been shown to play a role in the disruption of both normal differentiation and proliferation. In addition, RAS influences a number of intracellular signaling pathways, which impinge on proteins that regulate programmed cell death. In this study, we have examined whether this oncogene can influence the activation of the apoptotic...

inactive ras proteins in vivo. product binds specifically to catalytically The Saccharomyces cerevisiae CDC25 gene

BACKGROUND Glioma is one of the most aggressive and lethal human brain tumors. Accumulating evidence shows that microRNAs play important roles in cancers, including glioma. Previous studies reported that miR-124 levels were downregulated in glioma specimens. Here, we further investigate the potential role of miR-124 in glioma. METHODS The expression levels of miR-124 were detected in glioma s...

The metastatic properties of the methylcholanthrene-induced T-10 sarcoma tumor variants which originated in C3H x C57Bl/6 F1 mice are correlated with the relative expression of class I major histocompatibility complex antigens. Both the nonmetastatic and the highly metastatic clones were found to lack the H-2K region-controlled H-2Kb and H-2Kk antigens. However, the nonmetastatic clones express...

Using a neural transplantation model and retrovirus-mediated gene transfer, we have introduced the oncogenes v-Ha-ras and \-myr into the developing rat brain. Upon insertion of a construct encoding i-l la-ra.v and the Escherichia colt /3-galactosidase marker gene, the retroviral vector was found to be expressed in neurons, astrocytes, and endothelial cells of the graft. After latency periods of...

The highly conserved RAS-mitogen activated protein kinase (MAPK) signaling pathway is involved in a wide range of cellular processes including differentiation, proliferation, and survival. Somatic mutations in genes encoding RAS-MAPK components frequently occur in many tumors, making the RAS-MAPK a critical pathway in human cancer. Since the pioneering study reporting that let-7 miRNA acted as ...

We use the Drosophila melanogaster larval hematopoietic system as an in vivo model for the genetic and functional genomic analysis of oncogenic cell overproliferation. Ras regulates cell proliferation and differentiation in multicellular eukaryotes. To further elucidate the role of activated Ras in cell overproliferation, we generated a collagen promoter-Gal4 strain to overexpress Ras(V12) in D...

The critical pathways determining the resistance of tumor cells to ionizing radiation are poorly defined. Because the ras oncogene, a gene activated in many human cancers treated with radiotherapy, can induce increased radioresistance, we have asked which Ras effector pathways are significant in conferring a survival advantage to tumor cells. The phosphoinositide-3-kinase (PI3K) inhibitor LY294...