Cancer Res. 2008 Apr 15;68(8):3037-42.Click here to read Links

Gender-related survival differences associated with EGFR polymorphisms in metastatic colon cancer.

Press OA, Zhang W, Gordon MA, Yang D, Lurje G, Iqbal S, El-Khoueiry A, Lenz HJ.

Division of Medical Oncology, University of Southern California/Norris Comprehensive Cancer Center, Keck School of Medicine, Los Angeles, CA 90033, USA.

Evidence is accumulating supporting gender-related differences in the development of colonic carcinomas. Sex steroid hormone receptors are expressed in the colon and interact with epidermal growth factor receptor (EGFR), a gene widely expressed in colonic tissue. Increased EGFR expression is linked with poor prognosis in colon cancer. Within the EGFR gene there are two functional polymorphisms of interest: a polymorphism located at codon 497 (HER-1 R497K) and a dinucleotide (CA)(n) repeat polymorphism located within intron 1. These germ-line polymorphisms of EGFR were analyzed in genomic DNA from 318 metastatic colon cancer patients, 177 males and 141 females, collected from 1992 to 2003. Gender-related survival differences were associated with the HER-1 R497K polymorphism (P(interaction) = 0.003). Females with the HER-1 497 Arg/Arg variant had better overall survival (OS) when compared with the Lys/Lys and/or Lys/Arg variants. In males the opposite was true. The EGFR dinucleotide (CA)(n) repeat also trended with a gender-related OS difference (P(interaction) = 0.11). Females with both short <20 (CA)(n) repeat alleles had better OS than those with any long >or=20 (CA)(n) repeats. In males the opposite was true. Combination analysis of the two polymorphisms taken together also revealed the same gender-related survival difference (P(interaction) = 0.002). These associations were observed using multivariable analysis. The two polymorphisms were not in linkage disequilibrium and are independent of one another. This study supports the role of functional EGFR polymorphisms as independent prognostic markers in metastatic colon cancer. As a prognostic factor, these variants had opposite prognostic implications based on gender.

PMID: 18413774 [PubMed - in process]

Mol Cancer Res. 2007 Mar;5(3):283-93.Click here to read Links

Activation of the EGFR gene target EphA2 inhibits epidermal growth factor-induced cancer cell motility.

Larsen AB, Pedersen MW, Stockhausen MT, Grandal MV, van Deurs B, Poulsen HS.

Department of Radiation Biology, Section 6321, Copenhagen University Hospital, Blegdamsvej 9, DK-2100 Copenhagen, Denmark.

EphA2 overexpression has been reported in many cancers and is believed to play an important role in tumor metastasis and angiogenesis. We show that the activated epidermal growth factor receptor (EGFR) and the cancer-specific constitutively active EGFR type III deletion mutant (EGFRvIII) induce the expression of EphA2 in mammalian cell lines, including the human cancer cell lines A431 and HN5. The regulation is partially dependent on downstream activation of mitogen-activated protein kinase/extracellular signal-regulated kinase kinase and is a direct effect on the EphA2 promoter. Furthermore, EGFR and EphA2 both localize to the plasma membrane and EphA2 coimmunoprecipitates with activated EGFR and EGFRvIII. Ligand activation of EphA2 and EphA2 knockdown by small interfering RNA inhibit EGF-induced cell motility of EGFR-overexpressing human cancer cells, indicating a functional role of EphA2 in EGFR-expressing cancer cells.

PMID: 17374733 [PubMed

Stem Cells. 2007 Jun;25(6):1410-22. Epub 2007 Mar 1.Click here to read Links

Epidermal growth factor signaling mediated by grb2 associated binder1 is required for the spatiotemporally regulated proliferation of olig2-expressing progenitors in the embryonic spinal cord.

Hayakawa-Yano Y, Nishida K, Fukami S, Gotoh Y, Hirano T, Nakagawa T, Shimazaki T, Okano H.

Department of Physiology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan.

Gab1 (Grb2 associated binder1) has been identified as an adaptor molecule downstream of many growth factors, including epidermal growth factor (EGF), fibroblast growth factor, and platelet-derived growth factor, which have been shown to play crucial roles as mitotic signals for a variety of neural progenitor cells, including stem cells, both in vitro and in vivo. Here, we show that Gab1 deficiency results in a reduction in the number of Olig2-positive (Olig2(+)) progenitor cells in the developing mouse spinal cord after embryonic day 12.5 (E12.5), when gliogenesis starts in the pMN domain where the EGF receptor (EGFR) is expressed predominantly. Our in vitro analysis further revealed that Gab1 is essential for EGF-dependent proliferation of Olig2(+) progenitor cells derived from the E12.5 ventral and E14.5 dorsal but not ventral spinal cord, whereas Gab1 is always required for the activation of Akt1 but not of ERK1/2. Moreover, we found that the action of the Gab1/Akt pathway is context-dependent, since constitutively active Akt1 could rescue the proliferation defect only in the E12.5 spinal cord of the Gab1-deficient mouse in vitro. Finally, we demonstrated that EGFR-deficient mice and Gab1-deficient mice showed a similar reduction in the number of Olig2(+) progenitor cells in the developing spinal cord. These findings indicate that EGFR-mediated signaling through Gab1/Akt contributes to the sufficient expansion of Olig2(+) progenitor cells in a spatiotemporally regulated manner, which represents the origin of glial cells in the developing spinal cord. Disclosure of potential conflicts of interest is found at the end of this article.

PMID: 17332510 [PubMed - indexed for MEDLINE]







































EGFR expression and HER2/neu overexpression/amplification in endometrial carcinosarcoma.

Livasy CA, Reading FC, Moore DT, Boggess JF, Lininger RA.

Department of Pathology and Lab Medicine, University of North Carolina, Chapel Hill, NC 27599-7525, USA; Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC 27599-7525, USA.

OBJECTIVE.: Endometrial carcinosarcomas are aggressive biphasic neoplasms traditionally treated as a high-grade uterine sarcoma. Epidermal growth factor receptor (EGFR) and HER2/neu (HER2) tyrosine kinases have been implicated in the development and progression of several human cancers and are targets for therapeutic intervention. The aim of this study was to evaluate for HER2 and EGFR expression in cases of endometrial carcinosarcoma. METHODS.: Formalin-fixed, paraffin-embedded sections from 55 cases of confirmed endometrial carcinosarcoma were immunostained with commercially available antibodies to EGFR and HER2. Fluorescent in situ hybridization for HER2 gene amplification was performed on all cases showing 2+ or 3+ HER2 staining by immunohistochemistry. HER2 gene amplification and EGFR expression were correlated with several prognostic variables. RESULTS.: EGFR expression was identified in the majority of tumors (45/55, 82%). HER2 overexpression (3+) was seen in 14/55 (25%) cases and HER2 gene amplification was seen in 11 (20%) cases. EGFR expression and HER2 gene amplification did not show significant correlation with disease progression, disease-free survival or overall survival. The carcinomatous component of tumors more frequently showed HER2 overexpression as compared to the sarcomatous component (25% vs. 4%, P = 0.008). The sarcomatous component of tumors more frequently showed EGFR overexpression as compared to the carcinomatous component (44% vs. 24%, P = 0.04). CONCLUSIONS.: EGFR and HER2 appear to play a role in the carcinogenesis of endometrial carcinosarcomas. The carcinomatous and sarcomatous elements of these tumors showed consistent differences in HER2 and EGFR expression patterns supporting biologic differences between these components. Studies evaluating the clinical utility of HER2 or EGFR targeted therapy in these tumors appear warranted.

PMID: 16157366 [PubMed - as supplied


Humanization of a recombinant monoclonal antibody to produce a therapeutic HER dimerization inhibitor, pertuzumab.

Adams CW, Allison DE, Flagella K, Presta L, Clarke J, Dybdal N, McKeever K, Sliwkowski MX.

Genentech Inc., One DNA Way, South San Francisco, CA, 94080, USA, adams.camellia@gene.com.

Dimerization is essential for activity of human epidermal growth factor receptors (HER1/EGFR, HER2/ErbB2, HER3/ErbB3, and ErbB4) and mediates intracellular signaling events leading to cancer cell proliferation, survival, and resistance to therapy. HER2 is the preferred dimerization partner. Activation of HER signaling pathways may be blocked by inhibition of dimer formation using a monoclonal antibody (MAb) directed against the dimerization domain of HER2. The murine MAb 2C4 that specifically binds the HER2 dimerization domain was cloned as a chimeric antibody, humanized using a computer-generated model to guide framework substitutions, and variants were tested as Fabs. Pharmacokinetics and toxicology were evaluated in rodents and cynomolgus monkeys. Cloning the variable domains of MAb 2C4 into a vector containing human kappa and CH1 domains allowed construction of a mouse-human chimeric Fab. DNA sequencing of the chimeric clone permitted identification of CDR residues. The full-length IgG1 of variant F-10 was equivalent in binding to chimeric IgG1 and was designated pertuzumab (rhuMAb 2C4; Omnitarg). Pertuzumab pharmacokinetics was best described by a two-compartment model with a distribution phase of <1 day, terminal half-life of ~10 days, and volume of distribution of ~40 mL/kg that approximates serum volume. With the exception of diarrhea, pertuzumab was generally well tolerated in cynomolgus monkeys. Pertuzumab, a recombinant humanized IgG1 MAb, is the first of a new class of agents known as HER dimerization inhibitors. Inhibition of HER dimerization may be an effective anticancer strategy in tumors with either normal or elevated expression of HER2.

PMID: 16151804 [PubMed - as supplied by publisher]







































Prime-boost vaccination with plasmid and adenovirus gene vaccines control HER2/neu+ metastatic breast cancer in mice.

Wang X, Wang JP, Rao XM, Price JE, Zhou HS, Lachman LB.

Department of Experimental Therapeutics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA. xiaoyanwang@mdanderson.org

INTRODUCTION: Once metastasis has occurred, the possibility of completely curing breast cancer is unlikely, particularly for the 30 to 40% of cancers overexpressing the gene for HER2/neu. A vaccine targeting p185, the protein product of the HER2/neu gene, could have therapeutic application by controlling the growth and metastasis of highly aggressive HER2/neu+ cells. The purpose of this study was to determine the effectiveness of two gene vaccines targeting HER2/neu in preventive and therapeutic tumor models. METHODS: The mouse breast cancer cell line A2L2, which expresses the gene for rat HER2/neu and hence p185, was injected into the mammary fat pad of mice as a model of solid tumor growth or was injected intravenously as a model of lung metastasis. SINCP-neu, a plasmid containing Sindbis virus genes and the gene for rat HER2/neu, and Adeno-neu, an E1,E2a-deleted adenovirus also containing the gene for rat HER2/neu, were tested as preventive and therapeutic vaccines. RESULTS: Vaccination with SINCP-neu or Adeno-neu before tumor challenge with A2L2 cells significantly inhibited the growth of the cells injected into the mammary fat or intravenously. Vaccination 2 days after tumor challenge with either vaccine was ineffective in both tumor models. However, therapeutic vaccination in a prime-boost protocol with SINCP-neu followed by Adeno-neu significantly prolonged the overall survival rate of mice injected intravenously with the tumor cells. Naive mice vaccinated using the same prime-boost protocol demonstrated a strong serum immunoglobulin G response and p185-specific cellular immunity, as shown by the results of ELISPOT (enzyme-linked immunospot) analysis for IFNgamma. CONCLUSION: We report herein that vaccination of mice with a plasmid gene vaccine and an adenovirus gene vaccine, each containing the gene for HER2/neu, prevented growth of a HER2/neu-expressing breast cancer cell line injected into the mammary fat pad or intravenously. Sequential administration of the vaccines in a prime-boost protocol was therapeutically effective when tumor cells were injected intravenously before the vaccination. The vaccines induced high levels of both cellular and humoral immunity as determined by in vitro assessment. These findings indicate that clinical evaluation of these vaccines, particularly when used sequentially in a prime-boost protocol, is justified.

PMID: 16168101 [PubMed - in process]



Combined Radioimmunotherapy and Chemotherapy of Breast Tumors with Y-90-Labeled Anti-Her2 and Anti-CEA Antibodies with Taxol.

Crow DM, Williams L, Colcher D, Wong JY, Raubitschek A, Shively JE.

Department of Radioimmunotherapy, Division of Radiation Oncology, City of Hope National Medical Center, Duarte, California 91010, Division of Radiology, City of Hope National Medical Center, Duarte, California 91010, and Division of Immunology, Beckman Research Institute of the City of Hope, Duarte, California 91010.

Because breast cancer cells often express either Her2/neu or carcinoembryonic antigen (CEA) or both, these tumor markers are good targets for radioimmunotherapy using Y-90-labeled antibodies. We performed studies on nude mi

ce bearing xenografts from MCF7, a cell line that has low Her2 and CEA expression, to more accurately reflect the more usual situation in breast cancer. Although uptake of In-111 anti-CEA into tumors was lower than that for In-111-labeled anti-Her2, radioimmunotherapy (RIT) with Y-90 anti-CEA was equivalent to that of Y-90 anti-Her2. When either Y-90 antibody was combined with a split-dose treatment with Taxol, the antitumor effect was greater than with either agent alone. When Y-90 anti-CEA was combined with a single dose of Taxol, the results were equivalent to the split-dose regimen. RIT plus cold Herceptin had no additional effects on tumor size reduction over RIT alone. When animals were first treated with Y-90 anti-Her2 and imaged 1-2 weeks later with In-111 anti-CEA or anti-Her2, tumor uptake was higher for anti-CEA and improved over tumor uptake with no prior RIT. These results suggest that a split dose of RIT with anti-Her2 antibody followed by anti-CEA antibody would be more effective than a single dose of either. This prediction was partially confirmed in a controlled study comparing single- vs split-dose anti-Her2 RIT followed by either anti-Her2 or anti-CEA RIT. These studies suggest that combined RIT and Taxol therapy are suitable in breast cancers expressing either low amounts of Her2 or CEA, thus expanding the number of eligible patients for combined therapies. They further suggest that split-dose RIT using different combinations of Y-90-labeled antibodies is effective in antitumor therapy.

PMID: 16173788 [PubMed - as supplied by publisher]


Phase I clinical study of the recombinant antibody toxin scFv(FRP5)-ETA specific for the ErbB2/HER2 receptor in patients with advanced solid malignomas.

von Minckwitz G, Harder S, Hovelmann S, Jager E, Al-Batran SE, Loibl S, Atmaca A, Cimpoiasu C, Neumann A, Abera A, Knuth A, Kaufmann M, Jager D, Maurer AB, Wels WS.

Department of Gynecology and Obstetrics, University Hospital Frankfurt, Germany.

INTRODUCTION: ScFv(FRP5)-ETA is a recombinant antibody toxin with binding specificity for ErbB2 (HER2). It consists of an N-terminal single-chain antibody fragment (scFv), genetically linked to truncated Pseudomonas exotoxin A (ETA). Potent antitumoral activity of scFv(FRP5)-ETA against ErbB2-overexpressing tumor cells was previously demonstrated in vitro and in animal models. Here we report the first systemic application of scFv(FRP5)-ETA in human cancer patients. METHODS: We have performed a phase I dose-finding study, with the objective to assess the maximum tolerated dose and the dose-limiting toxicity of intravenously injected scFv(FRP5)-ETA. Eighteen patients suffering from ErbB2-expressing metastatic breast cancers, prostate cancers, head and neck cancer, non small cell lung cancer, or transitional cell carcinoma were treated. Dose levels of 2, 4, 10, 12.5, and 20 microg/kg scFv(FRP5)-ETA were administered as five daily infusions each for two consecutive weeks. RESULTS: No hematologic, renal, and/or cardiovascular toxicities were noted in any of the patients treated. However, transient elevation of liver enzymes was observed, and considered dose limiting, in one of six patients at the maximum tolerated dose of 12.5 microg/kg, and in two of three patients at 20 microg/kg. Fifteen minutes after injection, peak concentrations of more than 100 ng/ml scFv(FRP5)-ETA were obtained at a dose of 10 microg/kg, indicating that predicted therapeutic levels of the recombinant protein can be applied without inducing toxic side effects. Induction of antibodies against scFv(FRP5)-ETA was observed 8 days after initiation of therapy in 13 patients investigated, but only in five of these patients could neutralizing activity be detected. Two patients showed stable disease and in three patients clinical signs of activity in terms of signs and symptoms were observed (all treated at doses > or = 10 microg/kg). Disease progression occurred in 11 of the patients. CONCLUSION: Our results demonstrate that systemic therapy with scFv(FRP5)-ETA can be safely administered up to a maximum tolerated dose of 12.5 microg/kg in patients with ErbB2-expressing tumors, justifying further clinical development.







PMID: 15611632 [PubMed - as supplied by publisher]




Mutations in BRCA1 and BRCA2 show different expressivity wit

h respect to cancer risk, and allelic heterogeneity may be present in both genes. We collected 179 pedigrees with identified germline mutation (104 BRCA1 and 75 BRCA2), ascertained in six collaborating centers of the Italian Consortium for Hereditary Breast and Ovarian Cancer. Significant heterogeneity was detected for several variables, and a logistic regression model including age of diagnosis in the proband, presence of ovarian cancer in the family, presence of prostate or pancreatic cancer in the family, and presence of male breast cancer in the family proved to be effective in predicting the presence of a mutation in a gene rather than the other. Excess of familial aggregation of both breast and ovarian cancer was observed in both genes. Proportion of ovarian cancer was increased in the 5' portion of BRCA1, and presence of prostate or pancreatic cancer in a family was correlated with presence of ovarian cancer in BRCA2
PMID: 14531499 [PubMed - in process]


Flowchart: Preparation: Egfr 


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Breast Cancer

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Text Box: Egfr Colon Cancer




Text Box: GAB1