Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0677930 (primary tumor)
 20,210 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The presence of epidermal growth factor receptor (EGF-R) gene was determined in 84 patients with squamous cell carcinoma (SCC) of the oropharyngeal region--a highly prevalent, chewing-tobacco associated malignancy in India, using Southern hybridisation analysis of DNA extracted from primary tumor tissues. We observed a 3- to 8-fold amplification of EGF-R gene in 19/66 (29%) of the SCCs of the oral cavity, and about 30-fold EGF-R amplification in 2/18 (11%) hypopharyngeal cancers. Dot blot analysis of total RNA from several tumour tissues, revealed overexpression of the EGF-R gene in the examined patients, with the EGF-R gene amplified. 4 patients with single copy EGF-R gene, did not exhibit overexpression of the gene. Within our sample set, no correlation was evident between EGF-R gene amplification and clinico-pathological parameters of the malignancy. The amplification and overexpression of the EGF-R gene observed in the primary tumour tissues of 25% (21/84) of the human oropharyngeal cancers, indicate possible involvement of the gene in the pathogenesis of these cancers.
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PMID:Amplification and overexpression of epidermal growth factor receptor gene in human oropharyngeal cancer. 130 31

A strategy for improved treatment of malignant gliomas grade III-IV is presented. The strategy can briefly be described as surgical removal of the bulky tumor, high precision external irradiation of small brain volumes over and near the primary tumor area with high doses from proton beams, and thereafter treatment of spread cells with toxic radionuclides. Proton beams suitable for this are under development. The clinical effects of high single doses on malignant gliomas grade III-IV are presently tested with conventional gamma radiation. Targeting of spread glioma cells with toxic radionuclides tagged to epidermal growth factor, EGF, or to EGF-dextran is presently tested in experimental systems and can, in the near future, be tested in combination with local high doses of external proton radiation. The possibilities to combine proton beams with EGF-guided neutron capture therapy will be considered in a longer perspective.
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PMID:Strategy for planned radiotherapy of malignant gliomas: postoperative treatment with combinations of high dose proton irradiation and tumor seeking radionuclides. 131 Sep 61

Cathepsin D, an acidic protease normally acting in lysosomes, is overproduced both in vitro and in vivo in most breast cancer cells. The mechanism of gene regulation by estrogens and the biological and clinical significance of this overexpression in metastasis are reviewed. In MCF7 cells, cathepsin D is specifically and directly induced by estrogens and also induced by growth factors (EGF, IGF-I and bFGF), but this induction is dependent upon de novo protein synthesis. The mechanism of estrogen induction involves EREs located upstream from the gene. Our laboratory cloned the promoter region (-4kb) of cathepsin D of MCF7 cells and found EREs located in the proximal 5' region of the gene. In MDA-MB231 and BT20 cells, cathepsin D is overexpressed but not regulated by estrogens. Total cathepsin D concentration were assayed by IRMA in breast cancer cytosol routinely prepared for receptor assays. Several retrospective clinical studies indicate a significant correlation between high cathepsin D concentrations in the cytosol of primary breast cancer and further development of clinical metastasis. High cathepsin D concentration in the primary tumor may be either a consequence, or more likely a cause, of metastasis. Transfection experiments using cDNA-cathepsin D in rat tumoral cells facilitates their metastatic potential in nude mice (Garcia et al., Oncogene, 1990, 5, 1809-1814). The mechanism of cathepsin D action in facilitating metastasis is unknown and may involve proteolytic activity in an acidic compartment, and/or interaction with the Man 6P/IGFII receptor.
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PMID:[Mechanism of the overexpression of the cathepsin D gene in breast cancer and consequences in the metastatic process]. 182 91

Malignant progression in breast cancer represents the processes through which localized, hormone-dependent tumor cells become resistant to endocrine manipulations and metastasize to sites distant from the primary tumor. By selection in ovariectomized athymic nude mice, we have isolated a variant (MIII) of the hormone-dependent, poorly invasive, human breast cancer cell line MCF-7. MIII cells have lost their absolute requirement for estrogen to form proliferating tumors in nude mice. Furthermore, these tumors are significantly more invasive than the parental MCF-7 cell line. MIII cells retain some responsivity to estrogens and antiestrogens, indicating that they have progressed to a hormone-independent but hormone-esponsive phenotype. In an attempt to determine the nature of this process, we have compared the phenotype of MIII cells with that of other MCF-7 variants. These comparisons strongly suggest that the factors contributing to perturbations in antiestrogen sensitivity, hormone-dependent growth, metastatic potential and tumorigenicity are essentially independent of each other and acquired in a random manner. Loss of estrogen receptor expression and overexpression of EGF receptors tend to occur later in the process of malignant progression.
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PMID:The process of malignant progression in human breast cancer. 208 84

Monoclonal antibodies have been used to detect tumor cells in bone marrow of patients with neuroblastoma, breast cancer, small cell lung cancer, prostatic cancer and gastrointestinal carcinoma. By comparative analysis immunocytology proved to be more sensitive than conventional cytology and histology and had the additional advantage of specificity. A positive correlation exists between the presence of tumor cells in bone marrow and the extent of the primary tumor. The proliferative potential of the micrometastatic cells was assessed by characterization of EGF and transferrin receptors, tumorigenicity was shown by xenotransplantation experiments in nu/nu mice in a few instances. First follow-up studies indicate that the presence of disseminated tumor cells in bone marrow can be taken as predicting the subsequent development of overt metastasis.
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PMID:Detection, characterization and tumorigenicity of disseminated tumor cells in human bone marrow. 210 96

Epidermal growth factor (EGF-R) estrogen (ER) and progesterone (PR) receptors were evaluated in 89 primary breast cancers and 23 axillary lymph node metastases. About 57% of primary and 72.2% of metastatic tumors were EGF-R positive and median EGF-R levels were higher in metastatic deposits than in primary breast tumors (P less than 0.05). An inverse distribution of EGF-R and steroid hormone receptor positive tumors was found (chi 2 = 10.87; P less than 0.001 for PR and chi 2 = 5.01; P less than 0.05 for ER) and an interesting correlation between EGF-R expression in primary tumor and axillary lymph node involvement was demonstrated (chi 2 = 21.4; P less than 0.001). Immunohistochemical studies with a monoclonal antibody against EGF-R revealed the presence of EGF-R only in malignant cells. Our data suggest that EGF-R could identify a class of more aggressive breast tumors endowed with a higher metastatic potential and may therefore represent an unfavorable prognostic parameter in breast cancer.
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PMID:Epidermal growth factor receptor in human breast cancer: correlation with steroid hormone receptors and axillary lymph node involvement. 306 25

125I-EGF binding technique was used to demonstrate high affinity receptor binding for epidermal growth factor (EGF-R) in 72 human mammary carcinomas. 27% of the tumors were EGF-R positive and the presence of this receptor was correlated with receptor levels for estradiol, DNA-pattern, proliferative index, thymidine kinase, tumor size, number of lymph node metastases and 6-year relapse probability. Our results confirm previous reports of an inverse relation between the cellular content of EGF-R and ER. In addition, we could associate EGF-R positivity with an aneuploid DNA-pattern and an increased growth rate, as measured by proliferative index. No correlation was found between EGF-R positivity in the primary tumor and presence of axillary lymph node metastasis at the time of operation. The 6-year relapse rate was somewhat higher for patients whose primary tumors were EGF-R positive. Moreover patients who had lymph node metastases at the time of operation and EGF-R positive tumors experienced a significantly lower 6-year disease free survival rate as compared to those who were node negative and had receptor negative tumors. It remains to be shown whether EGF-R alone can be used as an independent prognostic factor.
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PMID:Prognostic significance of the receptor for epidermal growth factor in human mammary carcinomas. 363 6

We used standard karyotypic analyses of first-division cells to identify a subpopulation of cells in primary malignant gliomas with over-representation of chromosomes 7 and 22. These cells are a minor subpopulation in the primary tumor but become the dominant population after treatment in vitro of the cells with the chemotherapeutic agent 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU). The selection for a cell with this specific karyotypic abnormality suggests that these chromosomes contain genes important to the growth of BCNU-resistant cells. Southern blot hybridization analyses demonstrate an increased copy number of the genes encoding platelet-derived growth factor (PDGF) A-chain and B-chain, which have been mapped to chromosomes 7 and 22, respectively. Reverse transcription followed by polymerase chain reaction (RT-PCR) analysis demonstrates increased expression of these genes. In addition, these cells secrete a mitogenic factor that stimulates 3H-thymidine uptake in NIH 3T3 cells. This factor is sensitive to anti-PDGF antibodies and beta-mercaptoethanol, but not to anti-EGF antibodies. These data suggest that autocrine and/or paracrine mechanisms occur in human malignant gliomas, and that over-expression of PDGF may play a role in the growth of BCNU-resistant cells in these tumors.
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PMID:BCNU-resistant human glioma cells with over-representation of chromosomes 7 and 22 demonstrate increased copy number and expression of platelet-derived growth factor genes. 750 21

We report on the establishment and characterization of a scirrhous gastric cancer cell line, designated OCUM-2M, derived from a 49-year-old Japanese female. OCUM-2M was derived from a primary tumor of stomach taken by total gastrectomy. The cell line grew singly or in clusters in the cultured medium. The cell line continued to multiply for more than one year. Doubling time was 37.3 hours, chromosomal mode was 70. The DNA ploidy pattern was aneuploid and DNA index was 1.59. It produced several tumor-associated antigens such as CEA, CA19-9, SLX and SPan-1. The cell line was transplantable in athymic BALB/c nude mice, and histological findings of the xenografted tumor showed poorly differentiated adenocarcinoma. The growth of OCUM-2M was stimulated following the addition of EGF, b-FGF and KGF, and decreased following the addition of TGF-beta 1. This cell line is useful in vitro and in vivo systems for studies of the biology of scirrhous gastric carcinoma.
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PMID:[Establishment of a new scirrhous gastric cancer cell line OCUM-2M from a primary gastric tumor]. 773 Oct 88

EGFR was determined, before treatment; in tumors biopsies obtained from 109 consecutive patients with head and neck cancer (100 men and nine women), using iodine labelled recombinant EGF. The median age of the study population was 60 years. EGFR levels varied from 2 to 2302 fmol/mg membrane protein (median 71). There was a significant difference of distribution for EGFR levels between stages I and II tumors and stages III and IV tumors (P = 0.03). The EGFR cut-off value for overall survival was 120 fmol/mg protein and the median follow-up was 18 months (3-35) EGFR overexpression was associated with shorter relapse-free (P = 0.0125) and overall survival (P = 0.028). By multivariate analysis the only significant variables were EGFR for relapse-free survival and tumor staging and EGFR for overall survival. Analyzed in 60 patients treated by first-line chemotherapy CDDP-5FU, the longest survival was achieved for patients who had a complete response to chemotherapy and the lowest EGFR levels (P = 0.018). EGFR expression in the primary tumor allows survival among first line chemotherapy responder categories to be discriminated.
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PMID:[EGF receptor, a prognostic factor in epidermoid cancers of the upper aerodigestive tracts]. 774 4


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