Members of the receptor tyrosine kinase family, that include EGFR, ErbB-2/HER-2, ErbB-3/HER-3 and ErbB-4/ HER-4, are frequently implicated in experimental models of epithelial cell neoplasia as well as in human cancer...Members of the receptor tyrosine kinase family, that include EGFR, ErbB-2/HER-2, ErbB-3/HER-3 and ErbB-4/ HER-4, are frequently implicated in experimental models of epithelial cell neoplasia as well as in human cancers. Therefore, interference with the activation of these growth factor receptors represents a promising strategy for de- velopment of novel and selective anticancer therapies. Indeed, a number of inhibitors that target either EGFR or HER-2, with the exception of a few that target both; have been developed for treatment of epithelial cancers. Since most solid tumors express different ErbB receptors and/or their ligands, identification of inhibitor(s), targeting multiple EGFR family members may provide a therapeutic benefit to a broader patient population. Here we describe the significance of an ErbB family of receptors in epithelial cancers, and summarize different available therapeutics targeting these receptors. It also emphasizes the need to develop pan-ErbB inhibitors and discusses EGF-Receptor Related Protein, a recently isolated negative regulator of EGFR as a potential pan-ErbB therapeutic for a wide vari- ety of epithelial cancers.展开更多
The relationship between antiproliferative effect of human IFN γ EGF 3 fusion protein and the influence of EGF receptor binding activity has been studied on A431 cell line. Antiproliferative activity of human IF...The relationship between antiproliferative effect of human IFN γ EGF 3 fusion protein and the influence of EGF receptor binding activity has been studied on A431 cell line. Antiproliferative activity of human IFN γ EGF 3 was higher than that of its parent IFN γ. In the 125 I EGF receptor competition experiment, the inhibition of EGF receptor binding capacity on the target cells was observed in the treatments of human IFN γ or IFN γ EGF 3, but the later was more significant. Our data suggests that the antiproliferative effects by IFN γ and its fusion protein are closely related to their EGF receptor competitions.展开更多
A non-radioisotopic method was developed for the assay of epidermal growth factor receptor (EGFR). A peptide with twenty amino acid residues around Tyr 1173, the major phosphorylation site of EGFR, was cloned as a GST...A non-radioisotopic method was developed for the assay of epidermal growth factor receptor (EGFR). A peptide with twenty amino acid residues around Tyr 1173, the major phosphorylation site of EGFR, was cloned as a GST fusion protein and used as substrate. Anti-phosphoty-rosine monoclonal antibody PY99 was used for the determination of the extent of phosphorylation. Both the specificity and the sensitivity were substantially higher than that of the existing method. Km value of the fusion protein is much lower (10 μmol/L) than that of the synthetic peptide (110 μmol/L). The method can be applied to the measurement of the tyrosine kinase activity of c-erb B2 (Neu/HER2).展开更多
Three anti-EGF receptor MoAbs were used in these studies. Administration of MoAbs 3 and 176 inhibited tumor formation in nude mice by CNE-2, a poorly differentiated nasopharyngeal carcinoma cell line and A431, an epid...Three anti-EGF receptor MoAbs were used in these studies. Administration of MoAbs 3 and 176 inhibited tumor formation in nude mice by CNE-2, a poorly differentiated nasopharyngeal carcinoma cell line and A431, an epidermoid carcinoma cell line. When the same MoAbs were used in treatment against HeLa, a cervical carcinoma, tumor growth was not affected. The number of EGF receptors and apparent dissociation constants for ^(125)I-EGF on CNE-2 and A431 was 1.3×10^(?)/cell (Kd 7.7×10^(-8)mol/L) and 1.4×10~6/cell(Kd 2.4×10^(-9)mol/L), respectively. Both MoAbs 3 and 176, capable of competing with EGF for receptor binding, showed significant tumor growth inhibition. MoAb 101 was incapable of blocking the binding of EGF to its receptor, and not as effective as MoAbs 3 and 176 in tumor growth inhibition. Our observation is that the MoAb anti-EGF receptor is cytostatic rather than cytocidal, in vitro against CNE-2 and A431.展开更多
In order to study the mechanism of estrogen and other events involved in the development of breast cancer,we observed the cell growth as well as the expression of p185 and epidermal growth factor(EGF) receptor in huma...In order to study the mechanism of estrogen and other events involved in the development of breast cancer,we observed the cell growth as well as the expression of p185 and epidermal growth factor(EGF) receptor in human breast cancer cell line SK-BR-3 in the presence of estradiol(E2) using flow cytometry. The results showed that E2 could act to expedite the proliferation of breast cancer cells and promote DNA synthesis , and that the percentage in S phase rose significantly (E2 group 26. 7?2. 5,control group 21. 2?2.1, P<0. 05). Under E2 action,p185 presented a reduced expression (E2 35?5. 6, control 61?13.1, P<0. 05) while the EGF receptor expression was greatly enhanced (E, 39?6. 9, control 21?5. 4,P<0. 05),suggesting that EGF may play a more important role in early development of breast cancer.展开更多
基金Supported by grants from the National Institute of Aging (5RO1 AG14343) (APNM) and the Department of Veterans Affairs(APNM and AKR) and from The Susan G. Komen Foundation forBreast Cancer Research (AKR)
文摘Members of the receptor tyrosine kinase family, that include EGFR, ErbB-2/HER-2, ErbB-3/HER-3 and ErbB-4/ HER-4, are frequently implicated in experimental models of epithelial cell neoplasia as well as in human cancers. Therefore, interference with the activation of these growth factor receptors represents a promising strategy for de- velopment of novel and selective anticancer therapies. Indeed, a number of inhibitors that target either EGFR or HER-2, with the exception of a few that target both; have been developed for treatment of epithelial cancers. Since most solid tumors express different ErbB receptors and/or their ligands, identification of inhibitor(s), targeting multiple EGFR family members may provide a therapeutic benefit to a broader patient population. Here we describe the significance of an ErbB family of receptors in epithelial cancers, and summarize different available therapeutics targeting these receptors. It also emphasizes the need to develop pan-ErbB inhibitors and discusses EGF-Receptor Related Protein, a recently isolated negative regulator of EGFR as a potential pan-ErbB therapeutic for a wide vari- ety of epithelial cancers.
文摘The relationship between antiproliferative effect of human IFN γ EGF 3 fusion protein and the influence of EGF receptor binding activity has been studied on A431 cell line. Antiproliferative activity of human IFN γ EGF 3 was higher than that of its parent IFN γ. In the 125 I EGF receptor competition experiment, the inhibition of EGF receptor binding capacity on the target cells was observed in the treatments of human IFN γ or IFN γ EGF 3, but the later was more significant. Our data suggests that the antiproliferative effects by IFN γ and its fusion protein are closely related to their EGF receptor competitions.
基金the fund of Chinese Academy of Sciences (Grant No. KJ952-S1-15).
文摘A non-radioisotopic method was developed for the assay of epidermal growth factor receptor (EGFR). A peptide with twenty amino acid residues around Tyr 1173, the major phosphorylation site of EGFR, was cloned as a GST fusion protein and used as substrate. Anti-phosphoty-rosine monoclonal antibody PY99 was used for the determination of the extent of phosphorylation. Both the specificity and the sensitivity were substantially higher than that of the existing method. Km value of the fusion protein is much lower (10 μmol/L) than that of the synthetic peptide (110 μmol/L). The method can be applied to the measurement of the tyrosine kinase activity of c-erb B2 (Neu/HER2).
文摘Three anti-EGF receptor MoAbs were used in these studies. Administration of MoAbs 3 and 176 inhibited tumor formation in nude mice by CNE-2, a poorly differentiated nasopharyngeal carcinoma cell line and A431, an epidermoid carcinoma cell line. When the same MoAbs were used in treatment against HeLa, a cervical carcinoma, tumor growth was not affected. The number of EGF receptors and apparent dissociation constants for ^(125)I-EGF on CNE-2 and A431 was 1.3×10^(?)/cell (Kd 7.7×10^(-8)mol/L) and 1.4×10~6/cell(Kd 2.4×10^(-9)mol/L), respectively. Both MoAbs 3 and 176, capable of competing with EGF for receptor binding, showed significant tumor growth inhibition. MoAb 101 was incapable of blocking the binding of EGF to its receptor, and not as effective as MoAbs 3 and 176 in tumor growth inhibition. Our observation is that the MoAb anti-EGF receptor is cytostatic rather than cytocidal, in vitro against CNE-2 and A431.
文摘In order to study the mechanism of estrogen and other events involved in the development of breast cancer,we observed the cell growth as well as the expression of p185 and epidermal growth factor(EGF) receptor in human breast cancer cell line SK-BR-3 in the presence of estradiol(E2) using flow cytometry. The results showed that E2 could act to expedite the proliferation of breast cancer cells and promote DNA synthesis , and that the percentage in S phase rose significantly (E2 group 26. 7?2. 5,control group 21. 2?2.1, P<0. 05). Under E2 action,p185 presented a reduced expression (E2 35?5. 6, control 61?13.1, P<0. 05) while the EGF receptor expression was greatly enhanced (E, 39?6. 9, control 21?5. 4,P<0. 05),suggesting that EGF may play a more important role in early development of breast cancer.