Anti-apoptotic Ras signalling cascade

About: Anti-apoptotic Ras signalling cascade is a research topic. Over the lifetime, 1436 publications have been published within this topic receiving 151118 citations.

ras Oncogenes in Human Cancer: A Review

Abstract: Mutations in codon 12, 13, or 61 of one of the three ras genes, H-ras, K-ras, and N-ras, convert these genes into active oncogenes. Rapid assays for the detection of these point mutations have been developed recently and used to investigate the role mutated ras genes play in the pathogenesis of human tumors. It appeared that ras gene mutations can be found in a variety of tumor types, although the incidence varies greatly. The highest incidences are found in adenocarcinomas of the pancreas (90%), the colon (50%), and the lung (30%); in thyroid tumors (50%); and in myeloid leukemia (30%). For some tumor types a relationship may exist between the presence of a ras mutation and clinical or histopathological features of the tumor. There is some evidence that environmental agents may be involved in the induction of the mutations.

Targeting RAS signalling pathways in cancer therapy

Abstract: The RAS proteins control signalling pathways that are key regulators of several aspects of normal cell growth and malignant transformation. They are aberrant in most human tumours due to activating mutations in the RAS genes themselves or to alterations in upstream or downstream signalling components. Rational therapies that target the RAS pathways might inhibit tumour growth, survival and spread. Several of these new therapeutic agents are showing promise in the clinic and many more are being developed.

Phosphatidylinositol-3-oh kinase as a direct target of ras

Abstract: Ras (p21ras) interacts directly with the catalytic subunit of phosphatidylinositol-3-OH kinase in a GTP-dependent manner through the Ras effector site. In vivo, dominant negative Ras mutant N17 inhibits growth factor induced production of 3' phosphorylated phosphoinositides in PC12 cells, and transfection of Ras, but not Raf, into COS cells results in a large elevation in the level of these lipids. Therefore Ras can probably regulate phosphatidylinositol-3-OH kinase, providing a point of divergence in signalling pathways downstream of Ras.

NF-κB is a target of AKT in anti-apoptotic PDGF signalling

Abstract: The mechanisms of cell proliferation and transformation are intrinsically linked to the process of apoptosis: the default of proliferating cells is to die unless specific survival signals are provided1,2. Platelet-derived growth factor (PDGF) is a principal survival factor that inhibits apoptosis and promotes proliferation1, but the mechanisms mediating its anti-apoptotic properties are not completely understood. Here we show that the transcription factor NF-κB3,4,5 is important in PDGF signalling. NF-κB transmits two signals: one is required for the induction of proto-oncogene c-myc and proliferation, and the second, an anti-apoptotic signal, counterbalances c-Myc cytotoxicity. We have traced a putative pathway whereby PDGF activates NF-κB through Ras and phospatidylinositol-3-kinase (PI(3)K) to the PKB/Akt protein kinase and the IκB kinase (IKK); NF-κB thus appears to be a target of the anti-apoptotic Ras/PI(3)K/Akt pathway6,7. We show that, upon PDGF stimulation, Akt transiently associates in vivo with IKK and induces IKK activation. These findings establish a role for NF-κB in growth factor signalling and define an anti-apoptotic Ras/PI(3)K/Akt/IKK/NF-κB pathway, thus linking anti-apoptotic signalling with transcription machinery.