No abstract available.
Genes, ras* ; Humans*

No abstract available.
Genes, ras* ; Humans

A variety of molecules are involved in tumorigenesis,during which the RAS pathway-related molecules play key roles. RAS gene mutations exist in about 30% of human tumors;in some tumors(e.g. pancreatic adenocarcinomas),the mutation rates may rise to 75%-95%. Even in tumors without RAS mutations,the RAS pathway-related molecules can also be highly activated. RAS-GTPase-activating proteins(RASGAPs)are a group of tumor suppressors. They normally turn off RAS pathway by catalyzing the hydrolysis of RAS-GTP. However,the mutation or hypermethylation of their promoters will inactivate their roles and thus provide an alternative mechanism of activating Ras. This article reviews the research advances in the role of RASGAPs in the development of tumors.
Cell Transformation, Neoplastic ; DNA Methylation ; Genes, ras ; Humans ; Mutation ; Neoplasms ; ras GTPase-Activating Proteins

The gene is frequently mutated and abnormally activated in many cancers，and plays an important role in cancer development. Metabolic reprogramming occurs in malignant tumors，which can be one of the key targets for anti-tumor therapy. gene can regulate lipid metabolism through AKT-mTORC1 single axis or multiple pathways，such as lipid synthesis pathways and degradation pathways. Similarly，lipid metabolism can also modify and activate RAS protein and its downstream signaling pathways. This article overviews the current research progress on the interaction between lipid metabolism and ，to provide insight in therapeutic strategies of lipid metabolism for -driven tumors.
Genes, ras ; Humans ; Lipid Metabolism/genetics* ; Neoplasms/genetics* ; Signal Transduction ; ras Proteins/metabolism*

No abstract available.
Genes, ras* ; Humans* ; Lymph Nodes* ; Polymerase Chain Reaction*

The EGFR Tyrosine kinase inhibitors (TKIs) show significant clinical benefit in selected population with no smoking history, adenocarcinoma or mutations in EGFR gene. Mutations of K-ras gene are associated with resistance to EGFR TKIs. Three published studies of gefitinib experience from Korea are reviewed. Mutations of EGFR gene published up to now and correlation with response to EGFR-TKIs is summarized. This review also discusses the suggested mechanisms of acquired resistance to EGFR TKIs
Adenocarcinoma ; Genes, erbB-1 ; Genes, ras ; Korea ; Protein-Tyrosine Kinases* ; Smoke ; Smoking ; Tyrosine*

Animals ; Genes, BRCA2 ; Genes, erbB-1 ; Genes, erbB-2 ; Genes, p16 ; Genes, p53 ; Genes, ras ; Genetic Predisposition to Disease ; genetics ; Humans ; Pancreatic Neoplasms ; classification ; genetics ; pathology

No abstract available.
Colorectal Neoplasms* ; Electrophoresis* ; Genes, ras* ; Humans* ; Point Mutation* ; Polymerase Chain Reaction*

Cellular oncogenes are expressed as an intrinsic part of the transformed or neoplastic phenotype. More than 60 of the known cellular oncogenes play a specific role in normal cellular development and differentiation. To examine the correlation between ras oncogene expression and the development of cervical cancer, this study investigated the reactivity of cervical intraepithelial neoplasia(CIN) and carcinoma of the uterine cervix by using anti-ras P21 mouse monoclonal antibody. The expression of ras oncogene significantly increased with the grade of malignancy from 11% in severe dysplasia, 30% in carcinoma in situ, 43% in microinvasive carcinoma, to 53% in invasive cancer. The expression of ras oncogene was not correlated with histologic type, tumor size, and nodal status of cervical cancer. It was concluded that expression of ras oncogene is related to early phase of carcinogenesis and tumor invasion of carcinoma of the uterine cervix.
Animals ; Carcinogenesis ; Carcinoma in Situ ; Cervix Uteri* ; Female ; Genes, ras* ; Mice ; Oncogenes ; Phenotype ; Uterine Cervical Neoplasms

The present study was carried out to evaluate the correlation of metastasis and prognostic factors in squamous cell carcinoma of head and neck. Examination was performed on a series of thirty-seven patients who were confirmed to squamous cell carcinoma and its lymphatic metastasis by pathologist. Correlations of metastasis and other factors such as angiogenesis, histologic grading, and p53 expression and ras oncogene were studied. The depth of tumors was around 1 to 27mm. Twenty cases were more than 10mm deep, of which seventeen cases were shown lymphatic metastasis. Total score of histologic grading including keratinization, nuclear atypia, growth pattern and intensity of inflammation was ranged from 5 to 10 points. Of these factors, nuclear atypia with intensity of inflammation, and nuclear atypia with growth pattern was correlated with nuclear atypia each. For angiogenesis, number of new-formed vessels were counted 13 to 58 each. Twenty-eight cases were shown to lymphatic metastasis. No correlation with histologic grading and lymphatic metastasis was found. The results of immunohistochemical staining for p53 and ras oncogene revealed that positive cases were 16 and 22, negative for 21 and 15 each. However, both were not correlated with histologic grading and lymphatic metastasis. These results were revealed that angiogenesis was not correlated with lymphatic metastasis of squamous cell carcinoma arising in head and neck. Nuclear atypia with intensity of inflammation and dysplasia with growth pattern were correlated with histologic grading, which suggested that more careful and adequate advice is needed for effective treatment.
Carcinoma, Squamous Cell* ; Genes, ras ; Head* ; Humans ; Inflammation ; Lymphatic Metastasis ; Neck* ; Neoplasm Metastasis*