Quantitative in vivo immunohistochemistry of epidermal growth factor receptor using a receptor concentration imaging approach (original) (raw)
Related papers
Clinical Cancer Research, 2010
Purpose: Tissue biomarker discovery is potentially limited by conventional tumor measurement techniques, which have an uncertain ability to accurately distinguish sensitive and resistant tumors. Semiautomated volumetric measurement of computed tomography imaging has the potential to more accurately capture tumor growth dynamics, allowing for more exact separation of sensitive and resistant tumors and a more accurate comparison of tissue characteristics. Experimental Design: Forty-eight patients with early stage non-small cell lung cancer and clinical characteristics of sensitivity to gefitinib were studied. High-resolution computed tomography was done at baseline and after 3 weeks of gefitinib. Tumors were then resected and molecularly profiled. Unidimensional and volumetric measurements were done using a semiautomated algorithm. Measurement changes were evaluated for their ability to differentiate tumors with and without sensitizing mutations. Results: Forty-four percent of tumors had epidermal growth factor receptor-sensitizing mutations. Receiver operating characteristic curve analysis showed that volumetric measurement had a higher area under the curve than unidimensional measurement for identifying tumors harboring sensitizing mutations (P = 0.009). Tumor volume decrease of >24.9% was the imaging criteria best able to classify tumors with and without sensitizing mutations (sensitivity, 90%; specificity, 89%). Conclusions: Volumetric tumor measurement was better than unidimensional tumor measurement at distinguishing tumors based on presence or absence of a sensitizing mutation. Use of volume-based response assessment for the development of tissue biomarkers could reduce contamination between sensitive and resistant tumor populations, improving our ability to identify meaningful predictors of sensitivity. Clin Cancer Res; 16(18); 4647-53. ©2010 AACR.
Avances tecnológicos en nuevos marcadores en cáncer y en biología tumoral AACR
2012
Activated kinases that induce cell proliferation have been attractive targets for targeted cancer therapy development. Cancer cells could become dependent on tumor-specifi c activated kinases and this tendency has been coined oncogene addiction. Here, we investigated three activated kinase inhibitors: BRAF inhibitor, PLX-4032 analog, and the MEK inhibitors, CI1040 and PD0325901. We established a high throughput cellular approach to profi le 240 human tumor cell lines identifying genotype-correlated sensitivity or resistance. Proliferative, apoptotic and cell cycle arrest responses were measured using multiplexed high content screening with automated fl uorescence microscopy and image analysis based technology. Growth index was measured using nuclear dye. Activated caspase 3 antibodies were used for the apoptosis induction detection. Phospho-histone H3 antibodies were used to measure the cell cycle block. We generated cell line profi les to reveal drug sensitivity and resistance patterns that may correlate with the clinical genotype responses. Cell lines with BRAFV600E mutations showed overlapping sensitivity to all three MEK and BRAF inhibitors. RAS mutations confer resistance to the BRAF inhibitor and confer sensitivity to both MEK inhibitors. In addition, we used Alphascreen technology to measure phosphoERK across the 240 non-treated tumor cell line panel. We found that the majority of PLX-4032 sensitive cell lines expressed high levels of phosphoERK. In addition, we investigated BRAF, MEK and EGFR inhibitor combinations to evaluate potential synergies. This preclinical approach can be used to predict mechanisms of susceptibility or resistance to these agents which in turn could be used for the optimization of targeted cancer therapeutics.
A. Bateman, et al, Cancer Res., 60: 2492–2497, 2000
Cancer Research, 2000
The AACR-Pezcoller International Award for Cancer Research is given annually to a scientist anywhere in the world who has made a major scientific discovery in the field of cancer, who continues to be active in the field, and whose ongoing work holds promise for future substantive contributions to cancer research. The Award recognizes extraordinary basic or translational cancer research. The Award will be presented to a single investigator for his or her highly original work. Under extraordinary circumstances, two individuals may be selected to share the Award when their investigations are clearly related and have resulted in prizeworthy work. The Awardee will be selected by an international committee of AACR members appointed by the AACR President with the agreement of the Council of the Pezcoller Foundation. The selection will be based solely on the Awardee's scientific accomplishments without regard to race, gender, nationality, geographic location, or religious or political views. The Pezcoller Foundation was established in 1982 by Professor Alessio Pezcoller, a dedicated Italian surgeon who has made important contributions to medicine throughout his career and who, through his foresight, vision, and generous gift in support of the formation of the Foundation, stimulated others to make significant advances in cancer research. Over the past decade the Pezcoller Foundation, in collaboration with the E.S.O.-European School of Oncology, gave a major biennial award for outstanding contributions to cancer and cancer-related biomedical science. The American Association for Cancer Research (AACR) was founded in 1907 by eleven physicians and scientists dedicated to the conquest of cancer and now has over 15,000 members in more than 60 countries who are experts in basic, clinical, and translational cancer research. The AACR is dedicated to its mission of preventing and curing cancer through the communication of important scientific results in a variety of forums including publications, meetings, and training and educational programs. Because of the commitment of the Foundation and the AACR to scientific excellence in cancer research, these organizations are now collaborating annually on the presentation of this Award. This will strengthen international collaborations and will be a catalyst for advancements in cancer research internationally.
Under conditions of short-term hormone deprivation, epidermal growth factor (EGF) induces DNA synthesis, cytoskeletal changes, and Src activation in MCF-7 and LNCaP cells. These effects are drastically inhibited by pure estradiol or androgen antagonists, implicating a role of the steroid receptors in these findings. Interestingly, EGF triggers rapid association of Src with androgen receptor (AR) and estradiol receptor A (ERA) in MCF-7 cells or ERB in LNCaP cells. Here, we show that, through EGF receptor (EGFR) and erb-B2, EGF induces tyrosine phosphorylation of ER preassociated with AR, thereby triggering the assembly of ER/AR with Src and EGFR. Remarkably, experiments in Cos cells show that this complex stimulates EGF-triggered EGFR tyrosine phosphorylation. In turn, estradiol and androgen antagonists, through the Src-associated receptors, prevent Src activation by EGF and heavily reduce EGFR tyrosine phosphorylation and the subsequent multiple effects, including DNA synthesis and cytoskeletal changes in MCF-7 cells. In addition, knockdown of ERa or AR gene by small interfering RNA (siRNA) almost abolishes EGFR tyrosine phosphorylation and DNA synthesis in EGF-treated MCF-7 cells. The present findings reveal that steroid receptors have a key role in EGF signaling. EGFR tyrosine phosphorylation, depending on Src, is a part of this mechanism. Understanding of EGF-triggered growth and invasiveness of mammary and prostate cancer cells expressing steroid receptors is enhanced by this report, which reveals novel aspects of steroid receptor action. (Cancer Res 2005; 65(22): 10585-93) Note: A. Migliaccio and M. Di Domenico contributed equally to this work. Requests for reprints: Ferdinando Auricchio, Dipartimento di Patologia Generale,
Blocking EGFR in the liver improves the tumor-to-liver uptake ratio of radiolabeled EGF
Tumor Biology, 2010
Overexpression of epidermal growth factor receptor (EGFR) in several types of malignant tumors correlates with disease progression. EGFR could, therefore, be an excellent candidate for targeted radionuclide diagnostics. However, the high natural expression of EGFR in the liver may be problematic. The aim of this study was to improve the tumor-to-liver ratio of radiolabeled epidermal growth factor (EGF) by blocking its uptake by the liver with a nonradiolabeled EGFR-targeting molecule in tumorbearing mice. Intraperitoneally injected nonradiolabeled EGF was first evaluated as a blocking agent, preadministered at various time intervals before intravenous injection of 125 I-labeled EGF. The anti-EGFR Affibody molecule (Z EGFR:955 ) 2 was then assessed as a blocking agent of 111 In-labeled EGF in a dual isotope study (50, 100, and 200µg, preadministered 30 or 60 min before 111 In-EGF). The 30-min preadministration of nonradiolabeled EGF significantly decreased 125 I-EGF uptake in the liver, whereas uptake in the tumor remained unchanged. Furthermore, preadministration of only 50µg (Z EGFR:955 ) 2 as a blocking agent 30 min before the 111 In-EGF decreased the uptake of 111 In-EGF by the liver and increased its uptake by the tumor, thereby increasing the tumor-to-liver ratio sixfold. We conclude that the Affibody molecule (Z EGFR:955 ) 2 shows promise as a blocking agent that could enhance the outcome of radionuclide-based EGFRexpressing tumor diagnostics and imaging.