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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The varying tumor-biological behavior of ovarian carcinomas probably influences both their operability and response to chemotherapy, which are the most relevant prognostic factors. The phenotype of different ovarian carcinomas is obviously associated with an activation of the EGF/TGF-alpha signal pathway, including c-myc and c-jun expression. Analysis of EGF-R, TGF-alpha, c-myc and c-jun expression in 33 stage III/IV, and 2 stage I/II ovarian carcinomas with biochemical, molecular-chemical and immunohistochemical methods showed a correlation between the mRNA and protein levels of EGF-R and TGF-alpha for tumors with low or high expressing rates. However, the concentration of measurable free EGF-Rs seems to depend on the amount of TGF-alpha expression by the tumors. The EGF-R binding ligand TGF-alpha is produced by epithelial tumor cells; stromal cells are usually TGF-alpha-negative, as shown by immunohistochemistry. High expression rates of EGF-R. TGF-alpha and c-myc were detected in 6, 7, and 10 out of 35 ovarian carcinomas, respectively. C-jun mRNA was detected in 18/19 cases studied. Non-malignant tissues originating from myometrium or ovary expressed no (or only small amounts of) EGF-R or TGF-alpha mRNA, whereas a high c-myc expression was found in 1/7 normal myometria, and in 2/5 normal ovaries. There was no strong correlation between EGF-R/TGF-alpha and c-myc/c-jun expression.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Oncogene and growth factor expression in ovarian cancer. 150 88

The effect of 131I therapy was examined in 13 thyroid glands affected by Graves' disease 3 to 29 years after irradiation for hyperthyroidism. All of the patients had clinically palpable thyroid nodules. Two patients were in a latent hypothyroid, 6 in a euthyroid and 5 in a hyperthyroid state. The microscopic changes in the thyroids showed a pattern of multiple adenomatous nodules with cystic changes, marked oxyphilic cell changes with nuclear atypism and various degrees of chronic thyroiditis. Immunohistochemical staining for TG and T4 was negative to mildly positive in these oxyphilic cells and entirely negative for EGF and CEA. The DNA ploidy pattern was diploid pattern in 6 cases. One papillary-type microcarcinoma occurred, but there was no evidence of a relationship between the tumor and the irradiation. The pathologic findings in Graves' thyroid gland after 131I therapy are not specific, but pathologists should differentiate this lesion from adenomatous goiter, which occurs with no apparent cause, or from thyroid carcinoma because of the marked nuclear atypism of this lesion.
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PMID:Histologic changes in Graves' thyroid gland after 131I therapy for hyperthyroidism. 150 2

We have investigated the expression of epidermal growth factor receptor (EGF-R) in invasive cervical cancer tissue of the uterus to determine whether there is a relationship between the expression of EGF-R and lymph node metastasis. Frozen sections of surgical specimens from twenty patients with invasive cervical cancer were immunohistochemically stained by the alkalinephosphatase anti-alkalinephosphatase method. The monoclonal antibody 528 we employed reacts with the receptor binding epitope within the EGF molecule, indicating that monoclonal antibody 528 is competitive with ligands such as EGF. Immunohistochemical staining was carried out before and after dissociation of ligands from the cellular surface of the tumor by acid treatment. However, the staining was resulted in no difference between before and after acid treatment. Consequently, the expression of EGF-R was detected in all cancer tissues as well in some normal tissue such as basal cell layers of epidermis. The expression of EGF-R was related inversely with lymph node metastasis by Wilcoxon rank sum test (p less than 0.05). These findings suggest that the expression of EGF-R in cervical cancer does not always lead to tumor growth or tumor invasion, although it does in some types of cancer.
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PMID:[Immunohistochemical study on the expression of epidermal growth factor receptor (EGF-R) in invasive cervical cancer of the uterus]. 150 31

Normal human mammary epithelial cells (HMECs) proliferate in a serum-free defined growth medium in the absence of epidermal growth factor (Li and Shipley, 1991). Amphiregulin (AR) is a heparin-regulated, EGF-like growth factor. Our observation that one strain of HMECs produce AR mRNA (Cook et al., 1991 a) stimulated us to determine whether AR expression was a common phenomenon in HMECs and whether AR could act as an autocrine growth factor to support the EGF-independent growth of these cells. In this study, we detected high levels of AR expression in four separate HMEC strains while one immortal mammary cell line (HBL-100) and six mammary tumor-derived cell lines had low to undetectable levels of AR. The EGF-independent growth of HMECs was blocked by the addition of heparin or a monoclonal anti-EGF receptor antibody to the culture medium, implicating AR as an autocrine growth mediator. This hypothesis is further supported by the fact that medium conditioned by HMECs contains secreted AR protein. A mammary tumor-derived cell line, Hs578T, which proliferates in an EGF-independent manner, does not express detectable levels of AR and is not growth inhibited by heparin. Examination of the same cell types for expression of transforming growth factor type-alpha (TGF-alpha) mRNA revealed coordinate expression of AR and TGF-alpha in these cells. These data suggest that both AR and TGF-alpha mRNA are produced in much greater abundance by normal HMECs than in tumor-derived cells in culture, and that AR is an important autostimulatory factor for the growth of normal HMECs.
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PMID:Heparin inhibition of autonomous growth implicates amphiregulin as an autocrine growth factor for normal human mammary epithelial cells. 152 24

The expression of epidermal growth factor receptor (EGFR) was investigated in 67 cases of odontogenic cysts and 35 cases of odontogenic tumors using monoclonal antibody to EGFR (Biomarker, Israel) to determine the presence and significance of this transmembrane growth factor receptor. The cystic epithelial cells of odontogenic cystic lesions (keratocyst 60%; primordial cyst 75%; radicular cyst 35%; and follicular cyst 47.4%) were positive to EGFR staining. Cytochemical characterization of EGFR in those cystic epithelium was cell membrane positive type as in the normal epithelium. No expression of EGFR was found in the odontogenic tumors. This diversity of EGFR represents no binding activity of EGF, or loss of EGFR in the tumor cell upon EGFR mediated growth in odontogenic tumors was suggested a different tumor cell growth factor status or microenvironment in cell proliferation mechanism at the cellular level in cysts and tumors of odontogenic origin.
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PMID:Epidermal growth factor receptor in odontogenic cysts and tumors. 152 33

Seven human gastric cancer xenografts with different concentrations of EGF receptor were established in nude mice. The expression of EGF receptor in the tumors was demonstrated by Western blotting with anti-EGF receptor antibody, binding assay with 125I-EGF and immunohistochemistry with anti-EGF receptor antibody. Western blotting revealed EGF receptor doublet bands at molecular masses of 150 KDa and 170 KDa in all of the samples. The concentration of 125I-EGF binding activity in the tumors ranged from 36.0 to 11,000 fmol/mg protein, with a mean of 345 fmol/mg protein. EGF receptor was also demonstrated immunohistochemically on the apical border of the glands and the cell membrane of the tumor cells. There seemed to be a close correlation between the concentration of 125I-EGF binding activity and the doubling time of these tumors in nude mice (gamma = -0.68). However, no definite correlation was observed between EGF ligand binding and histological features of intestinal type or diffuse type. The expression of EGF receptor appears to facilitate the growth of human gastric cancer xenografts in nude mice.
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PMID:Correlation between epidermal growth factor receptor concentration and the growth of human gastric cancer xenografts in nude mice. 152 29

Four tumor promoters, i.e. PB, TPA, NAF, and DDT, added singly to a calcium-deprived synthetic medium, elicited early and late mitogenic effects and concurrent surges of nuclear poly(ADP-ribose) polymerase (pADPRP) activity in primary neonatal rat hepatocytes mutagenized with an intra-uterine dose of DMN. These actions were fully abated by the pADPRP inhibitor 3-MBA. Conversely, EGF only acted as a full mitogen when medium's calcium was at physiological levels, and its effects could not be blocked by 3-MBA. The same tumor promoters, but not EGF, also evoked a swift and lingering amplification of pADPRP transcripts in DMN-initiated hepatocytes kept in low-calcium medium. Hence, a coordinated modulation of both pADPRP transcripts and activity by xenobiotics is likely to be involved in the clonal expansion of early preneoplastic hepatocytes.
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PMID:The exposure of carcinogen-initiated primary neonatal rat hepatocytes to tumor promoters modulates both the transcripts and the enzymatic activity of nuclear poly(ADP-ribose) polymerase. 154 Jan 55

The very rapid growth rate (1 population doubling/day) of normal human epidermal keratinocytes (HK) cultured in serum-free medium can be utilized for wound closure in burn treatment. However, rapid growth in vitro may present the possibility of neoplastic transformation. To investigate this possibility, HK were cultured from primary isolation to large populations in MCDB 153 medium supplemented with epidermal growth factor (EGF, 10 ng/ml), insulin (5 micrograms/ml), hydrocortisone (0.5 micrograms/ml), and Bovine Pituitary Extract (BPE, 70 micrograms/ml). HK were studied for their ability to form tumors in athymic mice after subcutaneous inoculation. Sixteen separate HK strains were inoculated from primary cultures, or from secondary cultures either before or after storage in liquid nitrogen. Transformed cell lines, SCC 13 and FL, derived from human epithelial carcinomata were used as controls for tumor formation. HK formed no tumors (0/79) after 26 weeks incubation, SCC 13 formed nodular tumors (3/5) after 20 weeks incubation, and FL formed tumors (5/5) after 4 weeks incubation. HK cells were not found by histological examination of inoculation sites of keratinocyte cultures derived from primary culture from skin. In contrast, palpable tumors from both SCC 13 and FL were returned to tissue culture and continued to proliferate. These results support the conclusion that the rapid growth rate of human epidermal keratinocytes in vitro can be attributed to permissive culture conditions, and not to neoplastic transformation.
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PMID:Absence of tumorigenicity in athymic mice by normal human epidermal keratinocytes after culture in serum-free medium. 154 Sep 41

The expression of epidermal growth factor receptor (EGF-R) was examined in 27 primary human brain tumors (7 glioblastomas, 10 astrocytomas, 5 oligodendrogliomas, 1 schwannoma, 1 ganglioneuroma, 1 medulloblastoma, 1 ependymoma, 1 histiocytic lymphoma), in 6 brain metastases from lung carcinomas and in 20 meningiomas. Peritumoral tissues histologically normal excised surgically along with a large tumor were used as control. All plasma membranes from brain tissues tested showed specific EGF binding. The EGF receptor is expressed at low levels in the control human brain and at very high levels in 60% of the total intracranial tumors studied. When the various histological types of tumors were analyzed, the higher percentage of positive tumors was found with the meningiomas (85%) and the glioblastomas (71%), while the lower percentage of positivity was found with the oligodendrogliomas (40%) and the astrocytomas (30%). A good correlation between binding and total amount of EGF-R protein detected by Western Blot was also observed.
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PMID:Epidermal growth factor receptor in human brain tumors. 156 Jan 88

Recombinant tumor necrosis factor alpha (rTNF alpha; optimal dose 1000 U/ml) significantly increased the density of epidermal growth factor receptor (EGF-R) in three of four glioma cell lines in culture as determined by binding analysis of anti-EGF-R monoclonal antibody (mAb) 425. Since enhancement of EGF-R expression by rTNF-alpha was inhibited when cells were treated with the protein synthesis inhibitor cycloheximide, the effects of rTNF alpha may be protein-synthesis-dependent. The dose of rTNF alpha that was optimal for up-regulation of EGF-R on glioma cells did not inhibit the growth of these cells. 125I-labeled mAb 425 lysed glioma cells in culture following its internalization into the cells. After glioma cells had been treated with rTNF alpha, the growth-inhibitory effects of the mAb were significantly enhanced, probably a reflection of the increase in EGF-R density on the tumor cell surfaces. The rTNF alpha effects were specific to the EGF-R and did not affect unrelated glioma-associated antigens. In our previous clinical trials, 125I-labeled mAb 425 showed immunotherapeutic effects in glioma patients. The present study provides the basis for considerations of combined immunotherapy of glioma patients with 125I-labeled mAb 425 and rTNF alpha.
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PMID:Enhancement of epidermal growth factor receptor expression on glioma cells by recombinant tumor necrosis factor alpha. 156 13


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