Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0006826 (cancer)
 1,092,456 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The EGF-like domains of heregulin alpha, beta 1, beta 2, and beta 3 were fused to a truncated form of Pseudomonas exotoxin (PE38KDEL), which contains a modified carboxyl-terminal sequence, KDEL, that increases that toxin activity. The resulting chimeric toxins were produced in Escherichia coli, purified to near homogeneity, and shown to be cytotoxic to target cells with very high activity on HTB20, N-87 MCF-7, and HepG2 cells; high activity on A431 and MDA-MB468 cells; and low activity toward SK-OV3, L929, and KB cells. The fact that cytotoxicity did not correlate with the levels of erbB2 expression indicated that another receptor in the erb family might be involved. Accordingly, cytotoxicity assays were performed on NIH/3T3 cell lines transfected with EGFR, ErbB2, ErbB3, or ErbB4. The results indicate that the heregulin toxins target ErbB4 or possibly ErbB3 but not ErbB2.
Cancer Res 1995 Jan 01
PMID:Cytotoxic activity of chimeric toxins containing the epidermal growth factor-like domain of heregulins fused to PE38KDEL, a truncated recombinant form of Pseudomonas exotoxin. 780 44

Epidermal growth factor (EGF), its related peptide transforming growth factor (TGF-alpha) and their common receptor (EGFR) have been implicated in the control of cell proliferation and differentiation in the gastrointestinal epithelium and may play an important role in gastric carcinogenesis. We compared the immunohistochemical expression and topographic distribution of these peptides using Western blot analysis in gastric carcinoma precursor lesions and in non-cancer tissue. We observed: (i) increased and extended expression of TGF-alpha in normal mucosa and hyperplasia in carcinoma fields compared with non-cancer controls; (ii) increased expression of EGFR in intestinal metaplasia (IM) from carcinoma fields compared with controls; (iii) EGF expression was not detected in normal mucosa and only weakly in IM; (iv) coexpression of TGF-alpha/EGFR and EGF/EGFR was higher in intestinal metaplasia in carcinoma fields than in non-cancer controls. We conclude that altered expression of TGF-alpha/EGFR is associated with morphological changes during gastric carcinogenesis. In this regard increased expression of TGF-alpha is a very early event which is subsequently followed by up-regulation of EGFR and this has important biological and clinical implications.
Br J Cancer 1995 Jan
PMID:Expression of transforming growth factor alpha, epidermal growth factor receptor and epidermal growth factor in precursor lesions to gastric carcinoma. 781 44

Epidermal growth factor (EGF) is a mitogenic peptide that binds to surface membrane receptors (EGFR) of breast cancer cells. After binding, secondary transmitter molecules are activated by tyrosine phosphorylation of the intracellular receptor domaine. The activity of the EGF/EGFR system can be modulated by a variety of chemically unrelated compounds including cytostatic agents. The purpose of our present study was to determine the effects of mitotic inhibitors on EGF receptor binding on human breast cancer cells. We found that MDA-231 and MDA-468 cells bind substantially more [125I]EGF after preincubation with docetaxel, vinblastine and vincristine. This effect was concentration- and time-dependent, reaching a maximum at 3000 ng/ml and 48 h incubation for docetaxel, and 100 ng/ml and 48 h incubation for vinca alcaloids. Subsequent experiments showed an increase in the rate of EGF binding as well as maximal binding capacity. Scatchard analysis of binding experiments under equilibrium conditions indicated that this was due to an increase in the number of apparent EGF binding sites. Modulation of EGF receptor binding by docetaxel, vinblastine, and vincristine was not detectable when isolated membranes were used, indicating that intact cytoplasmatic mechanisms are required for the upregulation of EGF receptors.
Eur J Cancer 1994
PMID:Effects of the microtubule-disturbing agents docetaxel (Taxotere), vinblastine and vincristine on epidermal growth factor-receptor binding of human breast cancer cell lines in vitro. 783 45

The coexpression of EGFR and c-erbB-2 protein was examined immunohistochemically in a total of 62 freshly frozen specimens of colorectal cancer, and correlations between the coexpression of both receptors and their clinicopathological variables were analyzed. Positive staining of both receptors was found in 21 cases, and it was related to the degree of lymphatic or vascular invasion of cancer cell, the synchronous metastasis to liver or lung, and the most advanced stage (Dukes' D). Moreover, the incidence of the distant metastasis including metachronous metastasis to other organs such as liver, lung or peritoneum were significantly higher in the positive cases of both receptors. These results suggest that the coexpression of EGFR and c-erbB-2 protein may be related to the distant metastasis of colorectal cancer.
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PMID:[Immunohistochemical study of the coexpression of epidermal growth factor receptor (EGFR) and c-erbB-2 protein in colorectal cancer]. 790 10

Recent progress in molecular biology has revealed that the proliferation of breast cancer is controlled by various growth factors and their receptors. In particular, the amplifications and products of oncogenes which code growth factors and receptors can be different indicators of clinical malignancy from the conventional prognostic factors. We investigated the relation of c-erbB-2 and int-2 gene amplification, expression, ER and EGFR with clinical characteristics. In retrospective study, the cumulative 10-year survival rate of patients with c-erbB-2 and int-2 gene amplification was significantly lower than in patients without amplification. In 72 cases with tumor diameter less than 3.0 cm, which can be an indication of breast preservation surgery, the survival rates of patients in these gene amplified groups were significantly lower than in the non-amplified groups. As for prospective study, the results were the same as those from retrospective study. These data show that the cases with these gene amplification have a high biological malignancy and high risk of recurrence to distant organs, despite the small tumor diameter.
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PMID:[Abnormalities and clinical characteristics of growth factors and receptor systems in breast cancer]. 791 99

The effects of a short period of in vivo systemic rh-IFN-alpha/2b treatment on epidermal-growth-factor(EGFR)-, estrogen(ER)- and progesterone(PR)-receptor content in 11 primary human cervical tumors was investigated by the radioreceptorial technique. EGFR levels were found to be significantly higher in cervical tumors after rh-IFN-alpha/2b treatment with respect to basal levels. In 2 cases, immunohistochemical and cytofluorimetric analysis showed that rh-IFN-alpha/2b treatment induces an increase in EGFR immunoreactivity and in the fraction of EGFR-positive cells. No difference in ER and PR levels in cervical tumors before and after rh-IFN-alpha/2b treatment was observed. Our results suggest that rh-IFN-alpha/2b up-regulates EGFR in primary human cervical tumors in vivo.
Int J Cancer 1994 Sep 15
PMID:Effect of recombinant human interferon-alpha/2b on epidermal-growth-factor-, estrogen- and progesterone-receptor expression in primary cervical cancer. 792 66

Cell kinetic data are an important adjunct to histologically based tumor classifications and provide reliable information about future tumor behaviour. The growth fraction of 62 transitional cell carcinomas was assessed using Ki-67 and PCNA (Proliferating cell nuclear antigen/cyclin) immunostainings. Ki-67 recognises an unknown nuclear antigen expressed in dividing cells and requires the use of frozen sections. PCNA, a non histone nuclear protein, identifies proliferating cells within fixed, embedded tissue sections. The percentage of labeled cells was expressed as the labeling index (LI). The median LI in normal urothelium and transitional cell carcinoma were 0.5% and 8%, respectively for Ki-67, and 1.5% and 12% for PCNA. A general agreement between indices of cell proliferation and histological grade and stage was demonstrated. Although some discrepancies were observed, there was a strong correlation between Ki-67 and PCNA Lis (r = 0.8308, P < 0.01). In addition, tumor EGFR positive had PCNA values greater than those found in cancer EGFR negative (P = 0.01). These findings suggest that immunohistochemical nuclear labeling with anti-PCNA on routinely processed tissue is a simple technique for the assessment of transitional cell carcinomas.
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PMID:PCNA/cyclin expression in transitional cell carcinomas of the human bladder: its correlation with Ki-67 and epidermal growth factor receptor immunostainings. 793 59

For the integration of new cell biological prognostic factors in daily clinical practice, we need to know not only their prognostic power with respect to prediction of relapse free and overall survival, but also their possible relation to response to endocrine therapy or chemotherapy in order to select adequate treatment for each patient. A large number of cell biological parameters are currently available to predict the prognosis of patients with breast cancer, but it is still difficult to predict the response to treatment accurately. A valuable prognostic factor can be a worthless predictive factor for endocrine therapy or chemotherapy, and vice versa. High tumour levels of ER, PGR, AR and PS2 protein predict a relatively good response to endocrine therapy, whereas EGFR positivity, HER2/neu positivity, aneuploidy, high proliferation indices and possibly high u-PA levels indicate a good chance of a poor response to endocrine therapy in metastatic breast cancer. With respect to chemotherapy, a high proliferation rate and HER2/neu amplification predict a good response to therapy in metastatic disease, whereas MDR gene expression and possibly c-myc amplification are related to a worse response. In conclusion, the newer cell biological parameters can be used to select high and low risk patients and type of systemic treatment and can be used as targets for new treatment modalities.
Cancer Surv 1993
PMID:Prognostic factors and response to therapy in breast cancer. 801 96

Our primary objectives were to: 1) develop a system for the study of prostatic tumor evolution; and 2) examine the role of the epidermal growth factor/epidermal growth factor receptor (EGF/EGFR) pathway in prostate tumor progression. Adult human prostate epithelial cells previously immortalized by transfection with the SV40 T antigen gene (P69SV40T) produced tumors in only 2/18 mice with a 6 month latency period. Reinjection of cells recovered from these tumors after 1 or 2 cycles of growth in nude mice produced tumors in 2/4 and 2/3 mice with markedly decreased latent intervals of 12, 25, 25 and 25 days each. The chromosomal complement of each tumor was human, consistently pseudodiploid, and retained the Y chromosome. In both anchorage-independent and adherent cell growth assays, EGF stimulated proliferation by approximately 2-fold in both the parental P69SV40T line and the tumor sublines. The tumor sublines expressed less EGFR protein than the parental line, as assessed by Western immunoblotting and flow cytometric analysis. Immunoprecipitation revealed increased production of the 18 and 25 kDa TGF-alpha precursors parallel to decreases in detectable EGFR. The growth of both the parental P69SV40T line and the tumor sublines was inhibited by a neutralizing antibody to TGF-alpha under serum-free defined conditions. Inclusion of the TGF-alpha neutralizing antibody consistently inhibited the proliferation of the tumor sublines more than P69SV40T in both proliferation and [3H]thymidine incorporation assays. This finding suggests that the increased tumorigenicity and decreased latent interval observed among the human prostate tumor cells is partially due to activation of the TGF-alpha/EGFR autocrine network.
Int J Cancer 1994 Sep 01
PMID:Tumorigenicity of SV40 T antigen immortalized human prostate epithelial cells: association with decreased epidermal growth factor receptor (EGFR) expression. 807 59

The Distribution pattern and proportion of the positive cells of proliferating cell nuclear antigen (PCNA) were examined immunohistochemically to study the proliferative activities of 33 cases of carcinoma found at the confluence of the main hepatic ducts. Expressions of CEA, CA19-9 and EGF receptor (R) were further examined with serial histological sections and comparatively analyzed with the result of PCNA staining and the clinico-pathological features of the carcinoma. PCNA positive cancer cells were observed in greatest abundance at the deeply infiltrated region of the carcinoma. CEA and CA19-9 were also expressed most strongly in this region and a stromal staining pattern was predominant. However, negative or apical staining patterns of CEA and CA19-9 were more frequent in the surface or the lateral spreading regions of the carcinoma, where the PCNA positive cancer cells were fewer in number. EGFR expression was rarely observed in the present study.
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PMID:[Immunohistochemical detection of proliferating cell nuclear antigen (PCNA) in carcinoma at the confluence of the main hepatic ducts and its relationship to expression of CEA, CA19-9 and EGF receptor]. 809 56


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