Overexpression Of Epidermal Growth Factor Receptor Research Articles

The Effect of Helicobacter pylori on Epidermal Growth Factor Receptor-Induced Signal Transduction and the Preventive Effect of Celecoxib in Gastric Cancer Cells

Background/AimsHelicobacter pylori infection induces cyclooxygenase-2 (COX-2) and epidermal growth factor receptor (EGFR) overexpression, and these factors may engage in cross-talk. The aim of the present study was to evaluate the effect of H. pylori on EGFR signaling pathways and to determine whether celecoxib has an inhibitory effect on this pathway.MethodsThe AGS cell line was cocultured with H. pylori G27 and the isogenic cagE- mutant. The expression of COX-2, EGFR, heparin binding-epidermal growth factor (HB-EGF), and transforming growth factor-β (TGF-β) was measured by real time-polymerase chain reaction (RT-PCR). Next, Western blot analyses of COX-2, EGFR, total Akt, phosphorylated Akt (pAkt), and phosphorylated glycogen synthase kinase-3β (pGSK3β) were performed after incubating H. pylori-treated AGS cells for 24 hours with various concentrations of celecoxib (0, 10, 20, and 30 µmol/L).ResultsH. pylori infection upregulated the mRNA levels of COX-2, EGFR, HB-EGF, and TGF-β, as detected by RT-PCR. However, AGS cells treated with cagE- mutants, which have a defective type IV secretion system, did not exhibit EGFR upregulation. Celecoxib had inhibitory effects on the H. pylori-induced overexpression of COX-2 (p=0.015), EGFR (p=0.025), pAkt (p=0.025), and pGSK3β (p=0.029) by Western blot analysis.ConclusionsH. pylori with an intact type IV secretion system activated the COX-2 and EGFR-Akt pathways in the AGS cell line. As celecoxib exhibited inhibitory effects on the EGFR signaling pathway, the cross-talk of COX-2 and EGFR likely mediates H. pylori-induced gastric cancer.

Mitigation of Radiation-Induced Damage by Targeting EGFR in Noncancerous Human Epithelial Cells

Methyl-2-cyano-3,12 dioxoolean-1,9 diene-28-oate (CDDO-Me) is an antioxidative, anti-inflammatory modulator, which activates the nuclear factor-erythroid 2-related factor 2 (Nrf2)/antioxidant response element (ARE) pathway. While CDDO-Me has radioprotective activity through Nrf2 activation in vitro and in vivo, its ability to mitigate radiation-induced damage when provided after irradiation has not been studied. Here we investigated whether CDDO-Me mitigates ionizing radiation (IR)-induced DNA damage in immortalized normal human colonic epithelial cells (HCECs) and bronchial epithelial cells (HBECs). DNA damage and clonogenic survival were assessed after treatment with CDDO-Me postirradiation. We observed that treatment with CDDO-Me within 30 min after irradiation improved both DNA damage repair and clonogenic survival independently of Nrf2. CDDO-Me activates the epidermal growth factor receptor (EGFR) related DNA repair responses. In the presence of CDDO-Me, EGFR is phosphorylated and translocates into the nucleus where it interacts with DNA-PKcs. CDDO-Me-mediated mitigation activity can be abrogated through depletion of EGFR, ectopic overexpression of mutant EGFR or inhibition of DNA-PKcs. While post-treatment of CDDO-Me protected noncancerous HCECs and HBECs against IR, cancer cells (HCT116 and MCF7) were not protected by CDDO-Me. These results suggest that targeting EGFR using CDDO-Me is a promising radiation mitigator with potential utility for first responders to nuclear accidents.

Human epidermal growth factor receptor-2 overexpression and amplification in metastatic and recurrent high grade or type 2 endometrial carcinomas

IntroductionHuman epidermal growth factor receptor (HER)-2 overexpression or gene amplification is more common in high-grade or type 2 endometrial carcinomas. We assessed the discordance of HER-2 expression between primary and metastatic or recurrent endometrial carcinomas.Materials and methodsThirty-six primary, along with 14 metastatic and five recurrent tumors (matched to primaries), pathologically confirmed as high-grade or type 2 endometrial carcinomas, were submitted for immunohistochemistry (IHC) for HER-2. Fluorescence in situ hybridization was performed when the tumors showed HER-2 overexpression (≥2+ IHC score). The results of the IHC and fluorescence in situ hybridization assays were compared between the primary and metastatic or recurrent tumors. The relationships between HER-2 expression and clinicopathological factors or prognosis were investigated.ResultsHER-2 overexpression and HER-2 amplification (a ratio of HER-2 copies to chromosome 17 [CEP17] copies ≥2.2) were detected in 33.3% (twelve of 36 patients) and 5.6% (two of 36 patients) of primary tumors, respectively. HER-2 overexpression was not associated with clinicopathological factors or prognosis. In 19 tumor specimens obtained from metastatic or recurrent tumors, HER-2 overexpression and HER-2 amplification were detected in 57.9% (eleven patients) and 15.8% (three patients), respectively. HER-2 overexpression tended to predict a worse prognosis.ConclusionHER-2 expression in metastatic or recurrent tumors was more frequent than in matched primary high-grade or type 2 endometrial carcinomas. Trastuzumab in combination with cytotoxic chemotherapy may represent an alternative therapeutic option for these tumors.

Flavopiridol Synergizes with Sorafenib to Induce Cytotoxicity and Potentiate Antitumorigenic Activity in EGFR/HER-2 and Mutant RAS/RAF Breast Cancer Model Systems

Oncogenic receptor tyrosine kinase (RTK) signaling through the Ras-Raf-Mek-Erk (Ras-MAPK) pathway is implicated in a wide array of carcinomas, including those of the breast. The cyclin-dependent kinases (CDKs) are implicated in regulating proliferative and survival signaling downstream of this pathway. Here, we show that CDK inhibitors exhibit an order of magnitude greater cytotoxic potency than a suite of inhibitors targeting RTK and Ras-MAPK signaling in cell lines representative of clinically recognized breast cancer (BC) subtypes. Drug combination studies show that the pan-CDK inhibitor, flavopiridol (FPD), synergistically potentiated cytotoxicity induced by the Raf inhibitor, sorafenib (SFN). This synergy was most pronounced at sub-EC50 SFN concentrations in MDA-MB-231 (KRAS-G13D and BRAF-G464V mutations), MDA-MB-468 [epidermal growth factor receptor (EGFR) overexpression], and SKBR3 [ErbB2/EGFR2 (HER-2) overexpression] cells but not in hormone-dependent MCF-7 and T47D cells. Potentiation of SFN cytotoxicity by FPD correlated with enhanced apoptosis, suppression of retinoblastoma (Rb) signaling, and reduced Mcl-1 expression. SFN and FPD were also tested in an MDA-MB-231 mammary fat pad engraftment model of tumorigenesis. Mice treated with both drugs exhibited reduced primary tumor growth rates and metastatic tumor load in the lungs compared to treatment with either drug alone, and this correlated with greater reductions in Rb signaling and Mcl-1 expression in resected tumors. These findings support the development of CDK and Raf co-targeting strategies in EGFR/HER-2-overexpressing or RAS/RAF mutant BCs.

EGFR overexpressing cells and tumors are dependent on autophagy for growth and survival

Background and purposeThe epidermal growth factor receptor (EGFR) is overexpressed, amplified or mutated in various human epithelial tumors, and is associated with tumor aggressiveness and therapy resistance. Autophagy activation provides a survival advantage for cells in the tumor microenvironment. In the current study, we assessed the potential of autophagy inhibition (using chloroquine (CQ)) in treatment of EGFR expressing tumors. Material and methodsQuantitative PCR, immunohistochemistry, clonogenic survival, proliferation assays and in vivo tumor growth were used to assess this potential. ResultsWe show that EGFR overexpressing xenografts are sensitive to CQ treatment and are sensitized to irradiation by autophagy inhibition. In HNSSC xenografts, a correlation between EGFR and expression of the autophagy marker LC3b is observed, suggesting a role for autophagy in EGFR expressing tumors. This observation was substantiated in cell lines, showing high EGFR expressing cells to be more sensitive to CQ addition as reflected by decreased proliferation and survival. Surprisingly high EGFR expressing cells display a lower autophagic flux. ConclusionsThe EGFR high expressing cells and tumors investigated in this study are highly dependent on autophagy for growth and survival. Inhibition of autophagy may therefore provide a novel treatment opportunity for EGFR overexpressing tumors.

Epidermal growth factor receptor expression in laryngeal cancer predicts the effect of hypoxia modification as an additive to accelerated radiotherapy in a randomised controlled trial

Accelerated radiotherapy (AR) improves the poor prognosis associated with epidermal growth factor receptor (EGFR) overexpression frequently seen in head and neck carcinomas. Combining AR with carbogen and nicotinamide (ARCON) counteracts enhanced tumour cell proliferation- and hypoxia-related radioresistance. The purpose of this study was to investigate if EGFR expression levels are associated with response to ARCON in patients with carcinoma of the larynx.Patients (N=272) with advanced stage larynx carcinoma were randomised between AR alone and ARCON. Paraffin-embedded biopsies from these patients were processed for immunohistochemical staining of EGFR. EGFR fraction was quantitated by automated image analysis and related to clinical outcome.A large variation was observed in EGFR fraction between tumours with expression levels ranging from 0 to 0.93 (median fraction 0.4). No difference in 5-year locoregional control was found between low and high EGFR expressing tumours in the AR arm (69% versus 75%), which is in line with the established effect of AR in EGFR overexpressing tumours. There was, however, a significant association in the ARCON arm: patients with low EGFR levels had a better 5-year locoregional control (88% versus 72% p=0.02) and disease-specific survival (92% versus 77% p=0.01). ARCON improved locoregional control relative to AR only in patients with low EGFR expression (hazard ratio (HR) 0.34 p=0.009).In conclusion, only in tumours with a low EGFR fraction, adding hypoxia modification to AR has an additive beneficial effect on outcome. EGFR expression is a predictive biomarker for the selection of patients that will or will not respond to ARCON.

Scheduling of paclitaxel and gefitinib to inhibit repopulation for optimal treatment of human cancer cells and xenografts that overexpress the epidermal growth factor receptor

In clinical studies, evaluating the combination of chemotherapy and the epidermal growth factor receptor (EGFR) inhibitor gefitinib, treatments were administered concurrently, despite it being counter-intuitive to give a cytostatic agent concurrent with cycle-active chemotherapy. One strategy to enhance efficacy might be to give the agents sequentially, thus allowing selective inhibition of repopulation of cancer cells between doses of chemotherapy. Here, we evaluate the hypothesis that sequential administration might allow inhibition of repopulation by gefitinib, with tumor cells re-entering cycle to allow sensitivity to subsequent chemotherapy. Sequential and concurrent administration of paclitaxel and gefitinib were studied in vitro and in xenografts using EGFR over-expressing, EGFR-mutant, and EGFR wild-type human cancer cell lines. We evaluated cell cycle distribution and repopulation during treatment. The sequential use of gefitinib and paclitaxel to treat EGFR over-expressing A431 cells in vitro decreased repopulation compared to chemotherapy alone, and there was greater cell kill compared to concurrent treatment. In contrast, combined treatment led to greater growth delay than use of gefitinib alone for concurrent but not for sequential treatment of mice bearing A431 xenografts; concurrent treatment had greater effects to reduce functional vasculature in the tumors. Conversely, sequential treatment led to greater growth delay than concurrent treatment of EGFR-mutant HCC-827 xenografts that are sensitive to lower doses of gefitinib. These studies highlight the importance of considering effects on the cell cycle, and on the solid tumor microenvironment, including tumor vasculature, when scheduling cytostatic and cytotoxic agents in combination.

Evidence of epidermal growth factor receptor expression in uveal melanoma: Inhibition of epidermal growth factor-mediated signalling by Gefitinib and Cetuximab triggered antibody-dependent cellular cytotoxicity

Despite advances in surgery and radiotherapy of uveal melanoma (UM), many patients develop distant metastases that poorly respond to therapy. Improved therapies for the metastatic disease are therefore urgently needed. Expression of the epidermal growth factor receptor (EGFR), a target of kinase inhibitors and humanised antibodies in use for several cancers, had been reported.Forty-eight human UMs were analysed by expression profiling. Signalling was tested in three EGFR expressing UM cell lines by Western blotting using phosphorylation specific antibodies for EGFR and the downstream mediators AKT (v-akt murine thymoma viral oncogene homolog) and extracellular signal-regulated kinase (ERK). Evidence for signalling in tumours was obtained through the application of a UM-specific EGF-signature. The EGFR specific kinase inhibitor, Gefitinib and the humanised monoclonal antibody, Cetuximab, were tested for their effect on EGFR signalling. Natural killer cell mediated antibody-dependent cellular cytotoxicity (ADCC) and tumour necrosis factor α (TNF-α) release was analysed for Cetuximab.Fourteen of 48 UMs and three of 14 cell lines (over-)express EGFR, at least in part due to trisomy of the EGFR locus on chromosome 7p12. EGFR and the downstream mediator, AKT, are phosphorylated upon stimulation with EGF in EGFR expressing cell lines. EGFR over-expressing tumours but not EGFR negative tumours show an activated EGF-signature. Gefitinib inhibits EGFR and AKT phosphorylation and Cetuximab induces EGFR phosphorylation but inhibits signalling to AKT induced with EGF. Cetuximab triggers natural killer (NK) cells to lyse EGFR+ cell lines and to release TNF-α.EGFR appears suited as a novel molecular drug target for therapy of uveal melanoma.

Cetuximab promotes anticancer drug toxicity in rhabdomyosarcomas with EGFR amplification in vitro

Overexpression of human epidermal growth factor receptor (EGFR) has been detected in various tumors and is associated with poor outcomes. Combination treatment regimens with EGFR-targeting and cytotoxic agents are a potential therapeutic option for rhabdomyosarcoma (RMS) with EGFR amplification. We investigated the effects of combination treatment with actinomycin D and the EGFR-targeting agent cetuximab in 4 RMS cell lines. All 4 RMS cell lines expressed wild-type K-ras, and 2 of the 4 overexpressed EGFR, as determined by flow cytometry, real-time PCR and direct sequencing. Combination of cetuximab and actinomycin D was highly effective, synergistically inhibiting cell growth with a combination index of less than 1. Moreover, combination treatment with these two reagents increased the rate of apoptosis in EGFR-positive cells. Cetuximab has antitumor activity in EGFR-amplified RMS cells when combined with antitumor reagents, indicating that cetuximab is a potential therapeutic reagent for RMS with EGFR amplification.

-216G/T (rs712829), a functional variant of the EGFR promoter, is associated with the pleural metastasis of lung adenocarcinoma

Numerous mutations and variants in the epidermal growth factor receptor (EGFR) gene have been demonstrated to be associated with the occurrence, metastasis and prognosis of various types of tumors, including lung cancer. Thus, the present study aimed to investigate whether -216G/T (rs712829), a functional polymorphism of the EGFR promoter that is able to induce EGFR activation and overexpression, is associated with the pleural metastasis of lung adenocarcinoma. The study subjects were comprised of 326 patients with primary lung adenocarcinoma and 312 matched cases with pleural metastasis. The -216G/T genotypes were determined in all subjects by PCR amplification and direct DNA sequencing, and EGFR expression was also evaluated by immunohistochemical staining in the primary tumor tissues with various -216G/T genotype backgrounds. The results showed that the frequencies of allele T and genotypes G/T and T/T in the pleural metastasis group were significantly higher compared with those in the non-metastasis group, with adjusted ORs of 1.46 (95% CI, 1.015–1.963) for G/T and 1.97 (95% CI, 1.051–3.152) for T/T. Furthermore, the expression of the EGFR protein was higher in the primary lung adenocarcinoma tissues with -216T/T and -216G/T compared with those with -216G/G (P<0.05). These results collectively indicate that the -216G/T polymorphism in the EGFR promoter is associated with the risk of the pleural metastasis of lung adenocarcinoma and that this effect may be associated with -216G/T-induced overexpression of the EGFR protein.

Overexpression of epidermal growth factor receptor as a prognostic factor in colorectal cancer on the basis of the Allred scoring system

BackgroundOverexpression of epidermal growth factor receptor (EGFR) is found in many types of neoplasms. The aim of the study was to evaluate EGFR expression in colorectal cancer (CRC) specimens and to determine whether EGFR expression correlates with clinicopathological data and overall survival.Patients and methodsTissue specimens from 181 consecutive CRC patients treated at the Military Institute of Medicine in 2006–2010 were collected and examined for EGFR expression, by immunohistochemistry staining. The staining intensity and percentage of cells with membranous EGFR expression were scored and then grouped according to the parameters of the Allred Scoring system. Cutoff values were subjected to further statistical analysis. Univariate tests and a multivariate Cox proportional hazards model were used in data analysis.ResultsEGFR was overexpressed in 96 of 181 CRC specimens (53%). EGFR expression was not correlated with other clinicopathological variables. On univariate analysis, overexpression of EGFR, determined by PS (percentage score) (>3) and total score (sum of PS and intensity score) (>4), was associated with poor overall survival. On multivariate analysis, EGFR overexpression (PS > 3) was an independent adverse prognostic factor (hazard ratio [HR] 1.62; 95% confidence interval [CI]: 1.03–2.53). Elevated carcinoembryonic antigen (CEA) serum concentration before treatment, performance status (Word Health Organization [WHO]-2), and tumor localized in colon and liver metastases were also independent unfavorable prognostic factors.ConclusionEGFR overexpression (PS > 3) in a CRC patient population was an independent adverse prognostic factor. Implementation of the Allred Scoring system criteria into clinical practice might facilitate treatment decisions in CRC patients.

Regulation of glioma cell phenotype in 3D matrices by hyaluronic acid

Human glioblastoma multiforme (hGBM) is the most common, aggressive, and deadly form of brain cancer. A major obstacle to understanding the impact of extracellular cues on glioblastoma invasion is the absence of model matrix systems able to replicate compositional and structural elements of the glioma mass as well as the surrounding brain tissue. Contact with a primary extracellular matrix component in the brain, hyaluronan, is believed to play a pivotal role in glioma cell invasion and malignancy. In this study we report use of gelatin and poly(ethylene glycol) (PEG) based hydrogel platforms to evaluate the effect of extracellular (composition, mechanics, HA incorporation) and intracellular (epidermal growth factor receptor overexpression) factors on the malignant transformation of U87MG glioma cells. Three-dimensional culture platforms elicit significantly different responses of U87MG glioma cells versus standard 2D culture. Critically, grafting brain-mimetic hyaluronic acid (HA) into the hydrogel network was found to induce significant, dose-dependent alterations of markers of glioma malignancy versus non-grafted 3D gelatin or PEG hydrogels. Clustering of glioma cells was observed exclusively in HA containing gels and expression profiles of malignancy-associated genes were found to vary biphasically with incorporated HA content. We also found HA-induced expression of MMP-2 is blocked by +EGFR signaling, suggesting a connection between CD44 and EGFR in glioma malignancy. Together, this work describes an adaptable platform for manipulating the local extracellular microenvironment surrounding glioma cells and highlights the importance of developing such systems for investigating the etiology and early growth of glioblastoma multiforme tumors.

Impact of the new EGF receptor and ALK testing guideline on personalized lung cancer medicine.

All advanced-stage lung adenocarcinoma patients should be tested for EGF receptor (EGFR) mutations and for EML4–ALK translocations as a guide for selecting them for tyrosine kinase inhibitor (TKI) therapy. The new EGFR and ALK guideline provides useful recommendations for appropriate testing [1]. Lung tumors are the leading cause of cancerrelated mortality worldwide [2]. Almost 80% of cases are non-small-cell lung cancer (NSCLC) and extensive disease is present at the time of diagnosis in the majority of patients. Systemic treatment with chemotherapy has reached a plateau of 10–20% response rates and 4–5 months of progression-free survival (PFS), and has not improved in more than a decade [3–5]. A first milestone in a new era of targeted therapy for this disease was reached with the discovery of a subset of tumors carrying activating mutations of EGFR, which can be selectively blocked with TKIs such as erlotinib and gefitinib. Numerous clinical studies have demonstrated the efficacy of these TKIs in the treatment of EGFR-mutated lung tumors, with 55–83% response rates and 9–13 month PFS [6,7]. A second milestone was the discovery, in 2007, of the EML4–ALK translocation in 6.7% of Japanese NSCLC patients [8]. The translocation was later found in 4–7% of Chinese [9], European [10] and US patients [11]. When treated with a novel ALK inhibitor, crizotinib, these patients showed response rates of 57% with a PFS greater than 6 months [12]. As a result of these new developments, many laboratories worldwide are currently testing lung tumor samples for EGFR mutations and EML4–ALK fusions. In an effort to standardize testing practices, the College of American Pathologists, the International Association for the Study of Lung Cancer and the Association for Molecular Pathology constituted writing and advisory panels, presided by three cochairs, to

Chemotherapeutic Potential of 2-[Piperidinoethoxyphenyl]-3-Phenyl-2H-Benzo(b)pyran in Estrogen Receptor- Negative Breast Cancer Cells: Action via Prevention of EGFR Activation and Combined Inhibition of PI-3-K/Akt/FOXO and MEK/Erk/AP-1 Pathways

Inhibition of epidermal growth factor receptor (EGFR) signaling is considered to be a promising treatment strategy for estrogen receptor (ER)-negative breast tumors. We have investigated here the anti-breast cancer properties of a novel anti-proliferative benzopyran compound namely, 2-[piperidinoethoxyphenyl]-3-phenyl-2H-benzo(b)pyran (CDRI-85/287) in ER- negative and EGFR- overexpressing breast cancer cells. The benzopyran compound selectively inhibited the EGF-induced growth of MDA-MB 231 cells and ER-negative primary breast cancer cell culture. The compound significantly reduced tumor growth in xenograft of MDA-MB 231 cells in nude mice. The compound displayed better binding affinity for EGFR than inhibitor AG1478 as demonstrated by molecular docking studies. CDRI-85/287 significantly inhibited the activation of EGFR and downstream effectors MEK/Erk and PI-3-K/Akt. Subsequent inhibition of AP-1 promoter activity resulted in decreased transcription activation and expression of c-fos and c-jun. Dephosphorylation of downstream effectors FOXO-3a and NF-κB led to increased expression of p27 and decreased expression of cyclin D1 which was responsible for decreased phosphorylation of Rb and prevented the transcription of E2F- dependent genes involved in cell cycle progression from G1/S phase. The compound induced apoptosis via mitochondrial pathway and it also inhibited EGF-induced invasion of MDA-MB 231 cells as evidenced by decreased activity of MMP-9 and expression of CTGF. These results indicate that benzopyran compound CDRI-85/287 could constitute a powerful new chemotherapeutic agent against ER-negative and EGFR over-expressing breast tumors.

TH-C-141-02: Imaging of Targeted Cancer Therapy Using Multifunctional Liposomal Nanoprobes and MRI

Purpose: To develop a multifunctional liposomal nanoprobe that selectively binds to epidermal growth factor receptor (EGFR) over‐expressing tumor cells with an encapsulating a magnetic resonance (MR) imaging contrast agent, gadolinium (Gd) and conjugating an EGFR‐specific monoclonal antibody within liposome particles. The function of the probe is to target cancer overexpressing cells so that uptake of anti‐EGFR targeted therapeutic agents may be imaged. We tested our nanoprobe using a head and neck cancer cell line and Cetuximab, an anti‐EGFR drug. Methods: Encapsulation of Gd within liposome particles was optimized by combining Dipalmitoylphosphatidylcholine (DPPC), cholesterol, 1,2‐dioleoyl‐sn‐glycero‐3‐phospho‐ethanolamine‐N‐(biotinyl)(sodium salt) (DOPE‐Biotin), and Diethylenetriaminepentaacetic acid‐bis(stearylamide)‐Gd (DTPA‐BSA‐Gd). Avidin was included in the liposomal membrane to conjugate with biotin‐modulated anti‐EGFR antibody. The probes were characterized for size, surface potential and structural integrity with dynamic light scattering (DLS) and transmission electronic microscopy (TEM). In‐vitro targeting specificity of the probe was evaluated using fluorescence microscopy by comparing the binding capacity of a fluorescence‐labeled probe in a human head and neck cancer cell line, 15B (high EGFR overexpression) and a human embryonic kidney cell line, HEK293 (low EGFR control). Finally, the in vitro applicability of MRI contrast Gd within the probe was demonstrated by detecting cell‐bound particles with MR imaging. Results: Using TEM scanning, the probes were near spherical in shape and identical in particle size (∼100nm). The surface potential was +5.13mV. The EGFR‐specific targeting assay with fluorescence‐labeled probes showed significantly high occupancy of the probe on the surface of 15B cells in comparison with HEK293 cells. The T1 relaxation time of this EGFR‐specific probe attached to15B cells was measured to be 379.3 ms, shorter than that of control vector without anti‐EGFR conjugation (516.2 ms). Conclusion: We have demonstrated targeting specificity of a nanoprobe in discriminating high and low EGFR‐expressing cells. The incorporation of Gd revealed the cell‐targeting under MR imaging.

Epidermal growth factor receptor overexpression is a marker for adverse pathologic features in papillary thyroid carcinoma

BackgroundEpidermal growth factor receptor (EGFR) overexpression (EGFR-H) is implicated in thyroid carcinoma disease progression; however, the clinicopathologic significance of EGFR-H in tumors that harbor EGFR and/or v-Raf murine sarcoma viral oncogene homolog B1 (BRAF)(V600E) mutations is unknown. MethodsTissue microarrays from 81 patients who had undergone thyroidectomy for carcinoma from 2002–2011 were scored for EGFR expression using immunohistochemistry. Somatic mutations in EGFR exons 19 and 21 and BRAF were analyzed. Correlations between the EGFR immunohistochemistry, EGFR, and BRAF(V600E) mutations and the clinicopathologic features were assessed. ResultsEGFR-H was detected in 39.5% of carcinomas (n = 32) from patients with papillary (PTC, 46.2%, n = 18), follicular (29.6%, n = 8), and anaplastic (100.0%, n = 6) but not medullary (0.0%, n = 9) thyroid carcinoma. BRAF(V600E) mutations were identified in 22.2% of the carcinoma cases (n = 18, 15 PTCs and 3 anaplastic thyroid carcinomas). No somatic EGFR mutations were detected in any subtype. On PTC univariate analysis, EGFR-H correlated with increasing stage, extrathyroid extension, tumor capsule invasion, adverse pathologic features (any demonstration of extrathyroid extension, tumor capsule invasion, lymphovascular invasion, lymph node metastasis, and/or distant metastasis), and BRAF(V600E) mutations. On multivariate analysis, EGFR-H correlated with BRAF(V600E) mutations. In BRAF wild-type PTCs, the correlation between EGFR-H and adverse pathologic features approached statistical significance (P = 0.065). ConclusionsEGFR-H could be an important biomarker for aggressive PTCs, particularly in BRAF wild-type PTCs. Despite EGFR-H in PTC, follicular thyroid carcinoma, and anaplastic thyroid carcinoma by immunohistochemistry, somatic EGFR mutations were absent. Therefore, future investigations of EGFR should consider histologic and immunohistochemical methods, in addition to molecular profiling of thyroid carcinomas. This multimodal approach is particularly important for future clinical trials testing anti-EGFR therapy.

Treatment of brain metastases in non-small cell lung cancer (NSCLC) patients with epidermal growth factor receptor (EGFR) mutations: the role of EGFR tyrosine kinase inhibitors.

The brain is one of the most common sites for lung adenocarcinoma metastasis, which are found in almost 20-30% of patients with the disease (1). These patients have poor median survival, and more effective therapies are urgently required. Since traditional chemotherapy is less effective against metastatic brain tumors, radiotherapy remains the main therapeutic or palliative option for inoperable central nervous system (CNS) disease. Radiotherapy supplemented with steroids has yielded responses rates of 50-75% for intracranial lesions, providing rapid attenuation of neurologic symptoms and improvement of performance status (2). However, brain metastases still herald a poor prognosis with a median survival of less than six months (3). Age, performance status, control of primary tumor, extend of extracranial disease, number of brain metastases, aggressive treatment modalities like surgery or radiosurgery, but also biomarkers such as expression levels of vascular enthothelial growth factor (VEGF), cyclooxygenase-2, epidermal growth factor receptor (EGFR) overexpression, and EGFR mutations have been explored as prognostic factors for patients with CNS metastases (4).

Phase I study of cisplatin (cDDP)/hyperthermia (HT)/lapatinib (Lap) in patients (pts) with recurrent carcinoma of the uterine cervix (rCC) in previously irradiated area (PIA).

e16504 Background: Pts with rCC in PIA might benefit from cDDP plus HT. Lap inhibits the intracellular tyrosine kinase domain of the epidermal growth factor receptor (EGFR) and HER2. Overexpression of EGFR and HER2 is often seen in pts with CC and might be involved in chemotherapy resistance. Besides, preclinical data suggest a synergistic effect of combining cDDP and Lap. Therefore, this phase I dose-escalation study was performed to determine the maximum tolerated dose (MTD) of Lap added to fixed doses of cDDP and HT. Methods: Pts with rCC in PIA, adequate organ function and ECOG performance status 0-1 were scheduled for 6 weekly administrations of 70 mg/m2cDDP plus locoregional HT. Daily Lap was added on days 1-56, starting at a dose-level of 1000 mg. The MTD was defined as the highest dose where ≤1/6 pts experienced dose-limiting toxicity (DLT). Safety, pharmacodynamics (PhD) and response were assessed. Results: Eight pts were treated. The first 4 pts (2 each at dose 1000 mg and 750 mg) experienced DLT. Of the 4 pts treated at dose level -2 (500 mg), only 1 pt was able to complete the treatment as planned, 2 pts experienced a DLT and 1 pt was not evaluable (NE), because of early progressive disease (PD) (see Table). In the evaluable pts 1 PD, 4 stable diseases and 2 partial responses (PR) were observed. One patient with PR had a resection of the local recurrence. Analysis of the resected specimen showed a pathological complete response (pCR). Enumeration of circulating endothelial cells measured at baseline and during therapy did not show consistent results. The same applied for the PhD on Ki-67, p27Kip1and EGFR in pretreatment and on-therapy skin biopsies. Conclusions: It is not feasible to combine Lap with fixed doses of cDDP and HT in pts with rCC in PIA mainly due to increased cDDP-related toxicity. The observed pCR is intriguing and warrants further investigation of combining HER2-blockade and cDDP/HT. Clinical trial information: NL24464.078.08. [Table: see text]

Epidermal growth factor receptor as a prognostic predictor to chemoradiotherapy in the primary lesion of esophageal squamous cell carcinoma.

e15167 Background: Concurrent chemoradiotherapy (CCRT) is standard performed for patients with locally advanced esophageal squamous cell carcinoma (ESCC). Some reports have revealed that patients who responded well to CCRT had favorable outcomes, whereas poor responders conversely showed a worse prognosis. The aim of this study was to identify molecular markers predicting prognosis to CCRT. Methods: Forty-seven patients with locally advanced ESCC who were treated with CCRT were included in the present study.The regimen comprised 5-fluorouracil and cisplatinumcombined with radiation therapy (1.8-2Gy/day). The chemotherapy was repeated every 3 weeks and the total radical radiation dose was 60-64Gy.The clinicopathologic features, patterns of treatment failure, and survival data were compared with the expressions of epidermal growth factor receptor (EGFR), which were determined by immunohistochemistry in biopsy specimens obtained before treatment. Univariate and multivariate analyses were performed to determine the prognostic factors that influence patients survival. Results: Overall the indices of the overexprssions of EGFR (the percentage of immunoreactivetumor cells≥50%) in all patients were 59.6%. EGFR expression was no significantly associated with gender,age,tumor differentiation grade,tumor location,depth of invasion, and metastasis status except for lymph node status (P=0.011). A significant difference was seen in the overall survival between patients with or without EGFR overexpression group(P=0.024). However, overexpression of EGFR was not associated with local recurrence or distant metastasis.In addition, a relationship between overall survival and sex (P=0.021),age (P=0.018),T stage(P=0.035), and tumor location (P=0.023) was detected.Local recurrence was found has a relationship with T stage(P=0.015) and metastasis status (P=0.026),and distant metastasis was found has a relationship with age (P=0.048). Conclusions: EGFR overexpression determined in pretreatment biopsy specimens maybe a clinically useful biomarker for predicting the overall survival of ESCC patients.

Potentiation of cetuximab by inhibition of Tregs in metastatic squamous cell cancers of head and neck.

TPS6101 Background: There are few effective treatment options for patients with metastatic squamous cell cancers of head and neck (HNSCC). The only significant advance in the last few decades has been approval of cetuximab, a monoclonal antibody directed against the overexpressed epidermal growth factor receptor (EGFR). Despite its high specificity for EGFR, cetuximab as single-agent has resulted in response rates of only 13% and PFS of less than 2 months. Recent evidence suggests that cetuximab may induce tumor cell killing through an immune-mediated ADCC and not through blockade of EGFR signaling. Cetuximab binds EGFR on tumor cells making them targets for natural killer (NK) cell-mediated lysis. The effectiveness of cetuximab is limited by the tumor mediated immune-suppression that inhibits NK and other effector cells. This local and possibly generalized immune suppression is primarily mediated by regulatory T cells (Tregs) which inhibit NK cells and other effector cells. HNSCC tumors are highly immunosuppressive and characterized by marked and persistent elevation of inhibitory Tregs. The myelosuppression and immunosuppression caused by cyclophosphamide is dose dependent, and at lower doses cyclophosphamide has been shown to selectively deplete Tregs, restore NK cell activity and paradoxically induce auto-immunity. Objectives: To assess potentiation of clinical response by tracking PFS, OS and HRQOL and immune augmentation in tumor biopsies and blood samples. Methods: The current pilot study (n=15) will assess the hypothesis that Tregs, which are elevated in HNSCC, can be suppressed with cyclophosphamide and that this suppression can lead to improved anti-tumor responses mediated by cetuximab. Eligibility: Metastatic HNSCC progressed on initial chemotherapy or not a candidate for platinum Treatment: Daily oral cyclophosphamide 50 mg bid and weekly cetuximab (SOC). Patients will have blood collected for immune monitoring at weeks 0, 3, 6, 12 and pre and post treatment biopsies at week 0, 6. T cell subsets, NK cell function, Tregs, MDSC will be assessed at tumor site and in blood for immune response. Restaging CT scans will be done pretreatment and at weeks 6, 12. Clinical trial information: NCT01581970.