Search results for " RAS"
showing 10 items of 218 documents
Functional deficiencies of components of the MHC class I antigen pathway in human tumors of epithelial origin
2000
An association between oncogenic transformation and repression of different components of the MHC class I antigen processing machinery (APM) have been described in murine model systems. In order to discover whether a similar correlation exists, human tumor cell lines of distinct histology with altered ras protein were analyzed for the expression of APM components utilizing RT-PCR and Western blot analyses. A heterogeneous expression pattern of MHC class I antigens, TAP peptide transporter, proteasome subunits, proteasome activator PA28 and the chaperones calnexin, calreticulin as well as tapasin was displayed by these tumor cell lines. Single or combined deficiencies in the expression and/o…
The Long and Winding Road to Useful Predictive Factors for Anti-EGFR Therapy in Metastatic Colorectal Carcinoma: The KRAS/BRAF Pathway
2010
Monoclonal antibodies targeting the epidermal growth factor receptor (EGFR) have improved outcomes for patients with metastatic colorectal carcinoma. Among patients not carrying activating mutations in the KRAS gene, only a limited number will experience tumor response to these therapeutic agents. The role of BRAF mutations in determining resistance to this treatment is emerging through preclinical and clinical studies. Standardization and validation of laboratory mutation analysis is needed to allow an optimal use of anti-EGFR therapies in the management of colorectal carcinoma. Clinical single-arm and randomized studies were conducted both in first-line and refractory settings to evaluate…
Irinotecan or oxaliplatin: Which is the first move for the mate?
2020
Objectives: The aim of the present review is to discuss the potential link between RAS, BRAF and microsatellite instability (MSI) mutational patterns and chemotherapeutic agent efficacy [Irinotecan (IRI) vs. Oxaliplatin (OXA)], and how this can potentially influence the choice of the chemotherapy backbone. Methods: Following a review of the research literature, all pertinent articles published in the core journals were selected for the study. The inclusion criteria regarded relevant clinical and pre-clinical studies on the topic of interest (Relationship of OXA and IRI to KRAS/BRAF mutations and MSI). Results: Excision repair cross complementation group 1 (ERCC1) expression is inhibited by…
Establishment and comparative characterization of novel squamous cell non-small cell lung cancer cell lines and their corresponding tumor tissue.
2010
Abstract Background Cell lines play an important role for studying tumor biology and novel therapeutic agents. Particularly in pulmonary squamous cell carcinoma (SCC) the availability of cell lines is limited and knowledge about their representativeness for corresponding tumor tissue is scanty. Materials and methods We established three novel SCC cell lines from fresh tumor tissue of 28 donors, including 8 SCC. Two cell lines were derived from different localizations of the same donor, i.e. primary tumor and lymph node metastasis. This represents a so far unique combination in lung cancer. The genotypes, gene expression profiles and mutational status of epidermal growth factor receptor ( EG…
La qualità tecnologica utile di prodotti edilizi innovativi
2014
Ras family genes: An interesting link between cell cycle and cancer
2002
Ras genes are evolutionary conserved and codify for a monomeric G protein binding GTP (active form) or GDP (inactive form). The ras genes are ubiquitously expressed although mRNA analysis suggests different level expression in tissue. Mutations in each ras gene frequently were found in different tumors, suggesting their involvement in the development of specific neoplasia. These mutations lead to a constitutive active and potentially oncogenic protein that could cause a deregulation of cell cycle. Ras protein moderates cellular responses at several mitogens and/or differentiation factors and at external stimuli. These stimuli activate a series of signal transduction pathways that either can…
Reversible Pisa Syndrome in a patient with Parkinson's disease on rasagiline therapy
2013
Do personal characteristics affect the Rasch measures of perceived physical risk? A quantile regression approach
2012
This paper focuses on the measurement of the perception of healthy risk according to personal characteristics. The Physical Risk Assessment Inventory was adopted as measurement tool and it was administered to 551 students enrolled in the first and in the fifth classes of some high schools of Palermo. The analysis of the determinants of the perceived risk is based on its quantitative measures. Therefore the analysis has been developed into two tracks. First track is devoted to obtain a quantitative measure of the perceived risk: an Extended Logistic Rasch Model was used considering separately males and females. Results highlight the different perception of risk between males and females, alt…
Direct Identification of Each Specific Mutation in Codon 12 and 13 of ci-ki-ras2 by SSCP Analysis
1998
We compared the SSCP behaviour of the DNA fragments containing c-ki-ras 2 wild type 12 and 13 codons or each of the 12 possible point mutated sequences in these two codons. We found that a single electrophoresis condition was sufficient to distinguish each specific mutation from the other 11 and from the wild type sequence. This observation makes it possible to identify each specific mutation directly by SSCP without any need for reamplification and sequencing.