Epidermal Growth Factor Receptor Immunostaining Research Articles

Potential for Using EGFR Expression in Rhabdomyosarcoma, Osteosarcoma and Ewing’s Sarcoma: Clinicopathological and Prognostic Significance

Sarcomas are a heterogeneous group of malignant tumors that arise from mesenchymal cells and can arise anywhere in the body, whether it is soft tissue or bone. Epidermal growth factor receptor (EGFR) expression in pediatric sarcomas is explored in the current study. A key feature of EGFRs is their general involvement in signal transduction and oncogenesis, making them one of the most studied receptor protein-tyrosine kinase families. The study included 104 archived formalin-fixed paraffin-embedded blocks assessed using immunohistochemical stains for EGFR expression in rhabdomyosarcoma, osteosarcoma, and Ewing's sarcoma. EGFR gene copy number was analyzed by dual silver in situ hybridization (DISH). EGFR was positively expressed in 56.7% of pediatric sarcoma. Immunostaining for EGFR was significantly associated with deep large tumors, stage, and histologic grade. Significantly, lower chances of overall survival were observed with elevated levels of EGFR five years post-diagnosis. EGFR staining identified independent risk factors for poor patient outcomes. The results of in situ hybridization did not indicate EGFR gene amplification in any of the cases assessed. EGFR overexpression was an independent predictor of pediatric sarcoma outcome, which is highly associated with histologic grade and stage. Results indicate EGFR inhibitors should be potentiated and directed against pediatric sarcoma. KEYWORDS EGFR, Ewing’s sarcoma, osteosarcoma, rhabdomyosarcoma

Evaluation of pyruvate kinase M2 (PKM2) and epidermal growth factor receptor (EGFR) expression and their clinicopathologic significance in bladder urothelial carcinoma

Background: Growing interest have been recently directed towards roles of cancer metabolism in carcinogenesis with “Warburg effect” being the signature of cancer metabolism. Pyruvate kinase M2 (PKM2) is a crucial regulator of the Warburg effect. Epidermal growth factor receptor (EGFR) has been also involved in different metabolic pathways. Aim: This study aimed to investigate the immunohistochemical expression of PKM2 and EGFR in urothelial carcinoma. Furthermore, we analyzed the relation between PKM2 and EGFR with the available clinicopathologic parameters. Materials and Methods: PKM2 and EGFR immunostaining was performed on 70 specimens of urothelial carcinoma of the urinary bladder. Results: PKM2 was highly expressed in 62.9% of cases. High PKM2 expression was significantly associated with high-grade (P=0.003), muscle invasion (P=0.002), advanced T staging (P=0.001) and concomitant carcinoma in situ (P=0.013). EGFR expression was detected in 68.6% of cases. EGFR expression was significantly higher in high-grade tumors (P=0.013), muscle-invasive tumors (P

EGFR-PKM2 signaling promotes the metastatic potential of nasopharyngeal carcinoma through induction of FOSL1 and ANTXR2.

Nasopharyngeal carcinoma (NPC) is notorious for its aggressiveness and high metastatic potential. NPC patients with distant metastasis have a particularly poor prognosis; however, evaluating metastatic potential by expression profiles of primary tumors is challenging. This study aimed to investigate the association between activation of epidermal growth factor receptor (EGFR) signaling and NPC metastasis and the underlying mechanisms. We found an association between EGFR protein overexpression and intense EGFR immunostaining in NPC samples with advanced tumor node metastasis stage, clinical stage, and distant metastasis in NPC patients. Exogenous EGF stimulates NPC mobility and invasiveness in vitro. Activation of EGFR signaling prompted PKM2 translocation to the nucleus. Silencing either EGFR or PKM2 attenuates NPC cell aggressiveness in vitro and in vivo. Blocking EGFR signaling with cetuximab suppressed NPC cell invasiveness in vitro and metastatic potential in vivo. Comprehensive analyses of transcriptome profiles indicated that the EGFR-PKM2 axis activates a number of novel metastasis promoters, including F3, FOSL1, EPHA2, ANTXR2, and AKR1C2. Finally, we found that the metastasis-promoting function of the EGFR-PKM2 axis is dependent on nuclear PKM2 regulation of the transcription of metastasis-related genes, including FOSL1 and ANTXR2. Our study indicates that EGFR-PKM2 signaling promotes NPC cell invasion and metastasis through induction of FOSL1 and ANTXR2 and identifies EGFR as a promising biomarker for predicting the risk of distant metastasis.

EGFR amplification and expression in oral squamous cell carcinoma in young adults

The aim of this study was to investigate epidermal growth factor receptor (EGFR) gene alterations in two groups of patients with oral squamous cell carcinoma (OSCC) (a test group of subjects aged ≤40 years and a control group of subjects aged ≥50 years) and to associate the results with EGFR immunostaining, clinicopathological features, and the prognosis. Sixty cases of OSCC were selected (test group, n=21; control group, n=39). The tissue microarray technique was applied to ensure the uniformity of results. Gene amplification was analyzed by fluorescence in situ hybridization (FISH), and immunohistochemical staining for EGFR was analyzed using an automated imaging system. EGFR amplification was higher in the test group than in the control group (P=0.018) and was associated with advanced clinical stage (P=0.013), regardless of age. Patients with EGFR overexpression had worse survival rates, as did patients who had T3–T4 tumours and positive margins. EGFR overexpression has a negative impact on disease progression. Despite the higher amplification of EGFR in young adults, it does not significantly impact the survival rates of affected patients.

Epidermal growth factor receptor expression in carcinoma gallbladder: A prospective study in Indian scenario.

Gallbladder cancer (GBC) is an aggressive disease with poor prognosis and complete surgical resection offering the only cure. Increased epidermal growth factor receptor (EGFR) expression has been noted in various cancers including GBC. Several studies across the world have examined the expression of EGFR in GBC. This study has been done to see the EGFR expression in GBC in Indian context. Fifty cases of GBC were evaluated histopathologically using hematoxylin and eosin stained sections. Immunohistochemical assessment of EGFR expression was done, and scoring was done as per Kaufman et al. Data were collected, tabulated, and analyzed statistically by SPSS 16.0 version (Chicago, Inc., USA) software. Of 50 cases, 44 revealed EGFR over-expression while 6 were negative. Of the 44 cases, 10 had weak EGFR immunostaining intensity (1+), 26 had moderate (2+), and 8 showed strong EGFR immunostaining (3+). We found that most of the cases showing weak EGFR immunostaining intensity (1+) were well-differentiated tumor (70%) and cases with a strong EGFR immunostaining intensity (3+) were poorly differentiated cases of adenocarcinoma (75%). Moderately differentiated adenocarcinoma showed moderate EGFR immunostaining intensity (2+) in most of the cases (53.8%). EGFR is expressed in most of the cases of GBC. In well-differentiated adenocarcinoma, the EGFR expression is less compared to EGFR expression in poorly differentiated tumor, leading to the conclusion that the differentiation of the tumor and EGFR expression is inversely related. Thus, intensity of EGFR expression may correlate with aggressiveness of disease.

Immunohistochemical study of p53, Ki-67, epidermal growth factor receptor, and sex-determining region Y-box 2 in squamous cell carcinoma of tongue

Objective: Tongue cancer (TC) is one of the most common oral cancers. Prognostic evaluation of this tumor includes histologic grade and TNM stage. In this study, we evaluated the expression of p53, Ki-67, epidermal growth factor receptor (EGFR), and sex-determining region Y-box 2 (SOX2) and correlated it with the clinicopathologic variables to assess their potential for use as prognostic markers. We compared the p53 positive and negative group. Design: A retrospective and prospective study with 45 cases of biopsy proven TC which were studied for the expression of p53, Ki-67, EGFR, and SOX2. The results were correlated with known clinicopathologic variables using Chi-square test. The p53 positive and negative groups were compared. Materials and Methods: Archieved blocks of biopsy proven TC were retrieved. Using 4 micron sections of the blockes immunostaining for p53, Ki67, EGFR and SOX2 was done. Results: P53 expression was 68.9%, Ki-67 was 88.9%, EGFR was 48.9%, and SOX2 was 35.6%. Expression of p53 and Ki-67 did not show any correlation with any of the clinicopathologic variables. There was a statistically significant association between EGFR expression and lymph node (LN) positivity (P = 0.001). Stage of tumor and SOX2 positivity showed a significant correlation (P = 0.03). The comparison of p53 positive and negative groups did not reveal a significant difference. Conclusion: p53-negative TC is not significantly different from the p53-positive TC at presentation. The absence of mutant p53 in more than 30% TC points toward the possible etiological role of human papillomavirus in TC. Larger studies are needed to evaluate the possible use of EGFR for prediction of LN metastasis and SOX2 as a prognostic marker.

Rectal cancer: Dynamic contrast-enhanced MRI correlates with lymph node status and epidermal growth factor receptor expression

To evaluate correlations between dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and clinicopathologic data as well as immunostaining of the markers of angiogenesis epidermal growth factor receptor (EGFR) and CXC-motif chemokine receptor 4 (CXCR4) in patients with rectal cancer. Presurgical DCE-MRI was performed in 41 patients according to a standardized protocol. Two quantitative parameters (k21 , A) were derived from a pharmacokinetic two-compartment model, and one semiquantitative parameter (TTP) was assessed. Standardized surgery and histopathologic examinations were performed in all patients. Immunostaining for EGFR and CXCR4 was performed and evaluated with a standardized scoring system. DCE-MRI parameter A correlated significantly with the N category (P = 0.048) and k21 with the occurrence of synchronous and metachronous distant metastases (P = 0.029). A trend was shown toward a correlation between k21 and EGFR expression (P = 0.107). A significant correlation was found between DCE-MRI parameter TTP and the expression of EGFR (P = 0.044). DCE-MRI data did not correlate with CXCR4 expression. DCE-MRI is a noninvasive method which can characterize microcirculation in rectal cancer and correlates with EGFR expression. Given the relationship between the dynamic parameters and the clinicopathologic data, DCE-MRI data may constitute a prognostic indicator for lymph node and distant metastases in patients with rectal cancer.

Absence of Human Papillomavirus Infection and Activation of PI3K-AKT Pathway in Cervical Clear Cell Carcinoma

Cervical cancer is the second most common cancer in females worldwide, and the majority of squamous cell carcinomas and adenocarcinomas are associated with high-risk human papillomavirus (HPV) infection. However, the relationship between clear cell carcinoma of the cervix (CCCC) and HPV is unclear. In this study, we sought to determine if HPV infection is associated with CCCC and to elucidate the signaling pathways involved. We collected samples from 13 CCCC patients and collated the relevant clinicopathologic data. We then evaluated the presence of HPV types 16, 18, 31, 33, 35, 52, and 58 by broad-spectrum amplification by polymerase chain reaction and HPV types 39, 45, 51, 56, 59, and 68 by nested polymerase chain reaction assay that combines degenerate E6/E7 consensus primers and type-specific primers from extracted genomic DNA. Immunohistochemistry was used to analyze the expression of EGFR (epidermal growth factor receptor), HER2, PTEN (phosphatase and tensin homolog), phospho-AKT, phospho-mTOR (mammalian target of rapamycin), p16, and p53. EGFR and HER2 gene amplification was determined by fluorescence in situ hybridization. Patients with stage IB CCCC had a better 3-year overall survival rate compared with those with advanced-stage cancer (100% vs 44%; P = 0.014). High-risk HPVs were not detected in any of the cases examined. EGFR immunostaining was observed in 9 (75%) of 12 patients, HER2 in 3 (25%) of 12, PTEN in 6 (50%) of 12, and phospho-AKT in 7 (58%) of 12, and phospho-mTOR in 6 (50%) of 12. EGFR amplification could not be detected, but HER2 amplification was identified in 1 of (12.5%) 8 cases. Patients with stage I CCCC demonstrated good overall survival and rare recurrence. Clear cell carcinoma of the cervix is unrelated to high-risk HPV infection; hence, current vaccines will not prevent the incidence of CCCC. However, increased EGFR or HER2 expression or activation of AKT or mTOR was observed in all cases, indicating that inhibitors of tyrosine kinases or the AKT-mTOR pathway may be suitable treatment regimens for CCCC.

THE SIGNIFICANCE OF EPIDERMAL GROWTH FACTOR RECEPTOR AND SURVIVIN EXPRESSION IN BLADDER CANCER TISSUE AND URINE CYTOLOGY OF PATIENTS WITH TRANSITIONAL CELL CARCINOMA OF THE URINARY BLADDER.

To assess whether epidermal growth factor receptor (EGFR) and survivin immunostaining of tumour cells in urinary cytology and tissue of patients with bladder cancer has a prognostic significance. Prospective study Department of Surgery (Division of Urology), Mubarak Al-Kabeer Teaching Hospital and Faculty of Medicine, Kuwait University, Kuwait Urine cytology smears obtainedpriorto cystoscopy in patients with transitional cell carcinoma (TCC) of the bladder were immunostained for EGFR and survivin. Bladder cancer tissue resected at surgery was also immunostained for EGFR and survivin expression. Tissue expression of EGFR and survivin in TCC of the bladder was compared to their expression in urine cytology and relationship to tumour grade and stage. 178 patients were studied (43 newly diagnosed bladder cancer, 58 with recurrent TCC and 77 in disease remission). Twenty five patients with normal urothelium served as controls. The mean sensitivity of urine cytology, tissue survivin immunohistochemistry (IHC) and tissue EGFR IHC was 30.5%, 62% and 59% respectively. The corresponding mean specificity was 95%, 79% and 38% respectively. For grades 1, 2 and 3 bladder tumors, tissue expression positivity for EGFR was 47.8%, 92.9%, 100% and for tissue survivin it was 27.8%, 18.2% and 33.3% respectively. For grades 1, 2 and 3 bladder tumors, urine expression positivity for EGFR was 35.7%, 40% and 67.7% and for urine survivin it was 8.3%, 42.9% and 33.3% respectively. Positive EGFR immunostaining of urine cytology specimen or tumour tissue increases with histological grade of TCC of the bladder. Survivin expression is less consistent in both urine cytology specimen and tissue samples. EGFR immunostaining may provide a useful tool in the grading of bladder TCC and aid in the selection of patients that may benefit from administration of EGFR inhibitors.

Association between Osteopontin and EGFR Expression with Clinicopathological Parameters in Hepatocellular Carcinoma

Osteopontin (OPN) and epidermal growth factor receptor (EGFR) are important factors associated with tumor progression, invasion and metastasis in humans. The aim of this study was to assess the correlation of OPN and EGFR expression with hepatocellular carcinoma (HCC) progression. Expression of OPN and EGFR was assessed by immunohistochemistry in 100 HCC specimens. Immunostaining scores (0 to 400) were calculated from the percentage of cells (0 to 100) at each immunostaining intensity and the immunostaining intensity (0 to 4). The average immunostaining score for OPN was correlated with tumor grade (56.1 for grade I, 104.6 for grade II, and 141.2 for grade III; P = 0.023) and T stage (58.6 for stage T1, 85.9 for stage T2, 126.8 for stage T3, and 189.1 for stage T4; P = 0.029). Similarly, the average immunostaining score for EGFR was correlated with tumor grade (80.5 for grade I, 142.1 for grade II, 230.6 for grade III; P = 0.011) and T stage (96.4 for stage T1, 135.5 for stage T2, 221.3 for stage T3, and 261.4 for stage T4; P = 0.026). In addition, OPN and EGFR immunostaining scores were also correlated with M, N, and AJCC stages. In conclusion, higher expression of OPN and EGFR is significantly associated with advanced histological grades, advanced pathological stages and poorer survival rates in HCC. OPN and EGFR may be used as novel biomarkers for diagnosis or monitoring of progression of hepatocellular carcinoma.

Epidermal growth factor regulates connexin 43 in the human epididymis: role of gap junctions in azoospermia

Gap junctions (GJs) allow for direct communication between adjacent cells. They are composed of connexons consisting of transmembrane proteins, connexins (Cxs). The objectives of this study were to determine if GJ proteins GJA1 (Cx43), GJB1 (Cx32) and GJB2 (Cx26) are present in the epididymis of men with a normal epididymis, to assess whether or not Cx expression and localization are altered in azoospermic patients, and to determine if epidermal growth factor (EGF) regulates GJA1 expression. Epididymides were obtained from men with localized testis cancer with active spermatogenesis and histologically normal epididymal tubule (group 1), men with non-obstructive azoospermia secondary to Sertoli-cell only syndrome (group 2) and from azoospermic men with normal spermatogenesis and epididymal obstruction (group 3). Epididymides were subdivided into three segments: caput, corpus and cauda. Quantitative real-time RT-PCR was performed to assess GJA1, GJB1, GJB2 and EGF receptor (EGFR) mRNA levels in epididymides from patients from each group (all n=3, except n=1 for caput blockage). A human caput epididymal cell line was then used to determine the role of EGFR signaling on the regulation of human epididymal GJA1. Real-time RT-PCR analysis revealed that GJA1, GJB1, GJB2 and EGFR were expressed along the human epididymis. In the cauda epididymidis of group 2 and 3 men, we observed a significant decrease in GJA1 (P=0.0456 and P=0.0465, respectively) and GJB1 (P=0.0450 and P=0.0497, respectively) mRNA levels when compared with group 1 men. We also observed a decrease in EGFR mRNA levels (P=0.0358) in the cauda epididymidis of group 3 men when compared with group 1. Immunocytochemistry revealed that in the epididymis, GJA1 and EGFR were localized between basal and principal cells and between adjacent principal cells. In group 2 and 3 patients, however, we noted a dramatic increase in cytosolic immunostaining for both GJA1 and EGFR in both principal and basal cells. Using a human caput epididymal cell line derived from fertile men, we demonstrated that changes in GJA1 phosphorylation could be regulated by EGF (P=0.015) and the extracellular regulated kinase 1/2 signaling pathway (P=0.03). Furthermore, while the phosphoinositide-3-kinase (PI3K)/AKT signaling pathway did not alter GJA1 phosphorylation, treatment with PI3K/AKT inhibitor LY294002 significantly (P=0.024) inhibited the EGF-stimulated increase in GJA1 total protein levels at 24 h. Immunolocalization indicated that loss of PI3K/AKT signaling was associated with increased cytosolic localization of Cx43 in this cell line. Together, these data suggest that in azoospermic men decreased expression of EGFR may be responsible for decreasing GJA1 levels and increasing its cytosolic localization via the PI3K/AKT signaling pathway.

Su1251 Overexpression of EGFR in the Exocrine Pancreas Induces a Chronic Pancreatitis

Background and Aim: Chronic pancreatitis and pancreatic ductal adenocarcinoma (PDA) frequently overexpress epidermal growth factor receptor (EGFR) and EGF-family ligands. Although chronic pancreatitis is a risk factor for PDA, the relationship between chronic pancreatitis and PDA remains obscure. A critical obstacle to understanding the role of chronic pancreatitis in development of PDA is the lack of appropriate animal models for chronic pancreatitis with similar clinical courses as in human patients. Serine protease inhibitor Kazal type 1 (SPINK1: mouse homolog Spink3), which is also known as tumor associated trypsin inhibitor (TATI), is mainly produced in the pancreatic acinar cells. Recently, we showed that SPINK1 binds to EGFR to activate its downstream signaling. The present study aims to generate chronic pancreatitis model mice and assess the molecular events from chronic pancreatitis to PDA. Methods: 1) C57BL/6 female mice were repeatedly induced acute pancreatitis by using choline-deficient with ethionine (CDE) diet for 54 weeks. 2) To assess the molecular events caused by long term CDE diet treatment using Western blotting. 3) To further analyze the clinical importance of EGFR and SPINK1 in the chronic pancreatitis and PDA, we examined the expression of SPINK1 and EGFR. Immunohistochemical analyses were performed using human chronic pancreatitis and PDA samples. Results: 1) Histological evaluation revealed that chronic pancreatitis, characterized by acinar atrophy, fibrosis and well-developed tubular complexes (TCs), was observed after 24 wk of CDE-diet treatment. In spite of the severe pancreatic degeneration, neoplastic changes were not observed. 2) Expression of EGFR and its ligands (Spink3 and TGF α) and activation of K-Ras (GTP-Ras formation), which are frequently observed in human PDA, were indeed observed in parallel with TCs formation. In addition, cyclooxygenase-2 which induced by stimuli involved in inflammatory responses was also overexpressed. 3) In the human chronic pancreatitis samples, TCs were positive EGFR immunostaining. Furthermore, PDA cases were positive for both SPINK1 and EGFR immunoreactivity. Conclusion: We have successfully developed a chronic pancreatitis model with CDE diet. We also showed expression of EGFR and its potent ligands, phosphorylation of EGFR, and activation of K-Ras as the step of chronic inflammation. It was suggested that EGFR signaling cascades were important for the development from chronic pancreatitis to PDA. Howevere, chronic pancreatitis itself is not sufficient for the development of PDA. Further combinations of CDE-diet treatment with the administration of other promotion insults or genetic alterations may result in PDA development.

Su1252 Factors Predictive of Relapse, Cancer and Cyst Formation in Autoimmune Pancreatitis Patients

Background and Aim: Chronic pancreatitis and pancreatic ductal adenocarcinoma (PDA) frequently overexpress epidermal growth factor receptor (EGFR) and EGF-family ligands. Although chronic pancreatitis is a risk factor for PDA, the relationship between chronic pancreatitis and PDA remains obscure. A critical obstacle to understanding the role of chronic pancreatitis in development of PDA is the lack of appropriate animal models for chronic pancreatitis with similar clinical courses as in human patients. Serine protease inhibitor Kazal type 1 (SPINK1: mouse homolog Spink3), which is also known as tumor associated trypsin inhibitor (TATI), is mainly produced in the pancreatic acinar cells. Recently, we showed that SPINK1 binds to EGFR to activate its downstream signaling. The present study aims to generate chronic pancreatitis model mice and assess the molecular events from chronic pancreatitis to PDA. Methods: 1) C57BL/6 female mice were repeatedly induced acute pancreatitis by using choline-deficient with ethionine (CDE) diet for 54 weeks. 2) To assess the molecular events caused by long term CDE diet treatment using Western blotting. 3) To further analyze the clinical importance of EGFR and SPINK1 in the chronic pancreatitis and PDA, we examined the expression of SPINK1 and EGFR. Immunohistochemical analyses were performed using human chronic pancreatitis and PDA samples. Results: 1) Histological evaluation revealed that chronic pancreatitis, characterized by acinar atrophy, fibrosis and well-developed tubular complexes (TCs), was observed after 24 wk of CDE-diet treatment. In spite of the severe pancreatic degeneration, neoplastic changes were not observed. 2) Expression of EGFR and its ligands (Spink3 and TGF α) and activation of K-Ras (GTP-Ras formation), which are frequently observed in human PDA, were indeed observed in parallel with TCs formation. In addition, cyclooxygenase-2 which induced by stimuli involved in inflammatory responses was also overexpressed. 3) In the human chronic pancreatitis samples, TCs were positive EGFR immunostaining. Furthermore, PDA cases were positive for both SPINK1 and EGFR immunoreactivity. Conclusion: We have successfully developed a chronic pancreatitis model with CDE diet. We also showed expression of EGFR and its potent ligands, phosphorylation of EGFR, and activation of K-Ras as the step of chronic inflammation. It was suggested that EGFR signaling cascades were important for the development from chronic pancreatitis to PDA. Howevere, chronic pancreatitis itself is not sufficient for the development of PDA. Further combinations of CDE-diet treatment with the administration of other promotion insults or genetic alterations may result in PDA development.

Immunohistochemical discrimination of wild-type EGFR from EGFRvIII in fixed tumour specimens using anti-EGFR mAbs ICR9 and ICR10

Background:The human epidermal growth factor receptor (EGFR) is an important therapeutic target in oncology, and three different types of EGFR inhibitors have been approved for the treatment of cancer patients. However, there has been no clear association between the expression levels of EGFR protein in the tumours determined by the FDA-approved EGFR PharmDx kit (Dako) or other standard anti-EGFR antibodies and the response to the EGFR inhibitors.Method:In this study, we investigated the potential of our anti-EGFR monoclonal antibodies (mAbs; ICR9, ICR10, ICR16) for immunohistochemical diagnosis of wild-type EGFR and/or the type-III deletion mutant form of EGFR (EGFRvIII) in formalin-fixed, paraffin-embedded human tumour specimens.Results:We found that the anti-EGFR mAb in the EGFR PharmDx kit stained both wild-type and EGFRvIII-expressing cells in formalin-fixed, paraffin-embedded sections. This pattern of EGFR immunostaining was also found with our anti-EGFR mAb ICR16. In contrast, mAbs ICR10 and ICR9 were specific for the wild-type EGFR.Conclusion:We conclude that mAbs ICR9 and ICR10 are ideal tools for investigating the expression patterns of wild-type EGFR protein in tumour specimens using immunohistochemistry, and to determine their prognostic significance, as well as predictive value for response to therapy with EGFR antibodies.

Discordance between EGFR Expression and Clinicopathologic Parameters of Colorectal Adenocarcinoma in Taiwan

Dysregulation of epidermal growth factor receptor (EGFR) has been associated with colorectal cancer, but no evidence shows a relationship of EGFR expression to clinicopathological parameters in colorectal cancer in Taiwan. Immunohistochemical analysis of EGFR, Ki67, and p53 was performed in tissue microarray slides of 9 normal glandular tissues and 150 specimens including 49 well, 58 moderately, and 43 poorly differentiated colorectal adenocarcinomas. Differences in intensity of EGFR immunostaining and the percentages of Ki67 and p53 positive cells between normal and tumor specimens were evaluated using the Student t-test, one-way ANOVA, and linear regression analysis. Intensity of EGFR staining was weak and nuclear expression of Ki67 and p53 was scattered in all 9 control specimens. Expression of Ki67 and p53 but not EGFR was significantly higher in more advanced grades and TNM stages of colorectal adenocarcinoma than in normal controls. The percentages of Ki67 and p53 stained tumor cells were significantly higher in moderately (Ki67: 60.3 ± 6.5, p53: 47.6 ± 3.8) and poorly (Ki67: 61.8 ± 5.3, p53: 55.1 ± 4.1) differentiated tumor cells than in well differentiated (Ki67: 40.8 ± 4.4, p53: 39.8 ± 4.2) tumor cells. Additionally, the Ki67 and p53 staining intensity was also significantly correlated with the more advanced T, N and American Joint Committee on Cancer (AJCC) clinical stage of colorectal adenocarcinoma, suggesting their usefulness as biomarkers of colorectal adenocarcinoma progression. In conclusion, EGFR immunochemistry may not be a good method for pre-treatment evaluation of colorectal adenocarcinoma in Taiwan.

EGFR Expression Stratifies Oligodendroglioma Behavior

Epidermal growth factor receptor (EGFR) expression and signaling contribute to glioma biological features and, thus, are a target for new drug development. The role, if any, of EGFR in routine surgical neuropathological diagnostics is less clear. Herein, we describe prospective EGFR IHC analysis in an adult cohort comprising 750 infiltrative gliomas. EGFR expression increased with World Health Organization grade but did not significantly differ between grade-matched astrocytic and oligodendroglial tumors. Survival did not significantly differ by EGFR expression among astrocytic tumors adjusted for World Health Organization grade. However, grade II oligodendrogliomas with strong EGFR expression and 1p/19q codeletion showed reduced survival, compared with their codeleted counterparts with weaker EGFR expression. Surprisingly, an inverse phenomenon was found with grade III anaplastic oligodendrogliomas, in which stronger EGFR expression was a favorable marker for survival. Among all gliomas, the likelihood of EGFR amplification, as viewed by fluorescence in situ hybridization, increased with the strength of EGFR expression, and <1% of cases with weak or no EGFR immunostaining showed amplification. These data suggest that EGFR IHC is useful in certain circumstances (ie, it may help supplement 1p/19q prognostic information in oligodendroglial tumors and screen out cases that would not benefit from more costly EGFR fluorescence in situ hybridization analysis).

Increased epidermal growth factor receptor expression at the invasive margin is a negative prognostic factor in colorectal cancer

The receptor tyrosine kinase epidermal growth factor receptor (EGFR) is often expressed in solid malignant tumours, and the expression has been correlated to disease progression. Multiple new agents targeted against the EGFR have been developed during the last decade, but treatment selecting criteria are still not clear. This immunohistochemical study includes 386 colorectal cancer patients and focuses on EGFR expression variations within the tumour, comparing central parts to the invasive margin. Positive immunostaining for EGFR was evident in the central part in 176/386 (46%) of analyzed primary tumours. The invasive margin was positive in 222/386 (58%). A similar expression in both the central part and the invasive front was evident in 286/386 (74%). An increased score at the invasive margin compared to central parts (EGFR(i) ) was evident in 97/386 (25%) of the tumours. Moreover, the results show a significant survival disadvantage for the EGFR(i) group, both in potentially curatively resected colon cancer patients (n = 170, p = 0.01) and in potentially curatively resected colon and rectal cancer patients combined (n = 273, p = 0.013). Multivariate survival analysis adjusted for age, gender, bowel localisation, grade, stage and tumour type showed an increased risk of cancer death for EGFR(i) tumours (HR, 1.53; 95% CI, 1.04-2.23; p = 0.029). A significant correlation between EGFR expression at the invasive margin and the presence of budding was seen (p = 0.0001). This investigation of a large patient material implies that EGFR immunohistochemical analysis still has a role in risk evaluation of colorectal cancer patients.

EGFR in melanoma: clinical significance and potential therapeutic target

The role of epidermal growth factor receptor (EGFR) has been established in a range of neoplasms. In melanoma, data on EGFR protein expression are conflicting. Fluorescence in situ hybridization (FISH) analysis for EGFR gene expression in melanoma showed EGFR gene amplification to be linked with worse prognosis. Cetuximab has been shown to suppress the formation of metastasis in mice. EGFR protein expression and gene copy number status were evaluated by means of immunohistochemistry and FISH in melanoma samples of patients with known clinicopathological data. Associations between EGFR expression and prognostic parameters were investigated. The effect of different cetuximab concentrations on the BLM melanoma cell line was evaluated by means of methyl tetrazolium (MTT), sulforhodamine B (SRB) and Matrigel invasion assays. EGFR protein expression was more frequently observed in patients with a positive sentinel lymph node. However, EGFR immunostaining has no predictive value. The presence of EGFR polysomy was associated with thicker tumors. Treatment of the BLM melanoma cell line with different concentrations of cetuximab reduced the invasive capacity of the cells, but did not alter cell viability or growth. EGFR appears to be involved in progression and metastasis of a subset of melanomas. Targeting EGFR could therefore represent a therapeutic option for these melanomas.

The epidermal growth factor receptor pathway in relation to pelvic lymph node metastasis and survival in early-stage cervical cancer

The objective of this study is to correlate the expression of epidermal growth factor receptor (EGFR) components with clinical behavior of early-stage cervical cancer. Tissue samples of 336 consecutive Federation of International Gynecologists and Obstetricians stage IB-IIA cervical cancer patients all treated primarily by radical surgery were collected. Clinicopathologic and follow-up data were prospectively obtained during standard treatment and follow-up. As representatives for the EGFR pathway, expression of EGFR, pEGFR, PTEN, pAKT, and pERK was assessed by immunohistochemistry on tissue microarrays. Positive immunostaining was observed for EGFR in 32.1%, for pEGFR in 21.0%, for PTEN in 38.3%, for pAKT in 5.3%, and for pERK in 4.3% of tumor samples. Positive EGFR immunostaining was associated with squamous cell carcinoma of the cervix (odds ratio [OR], 7.41; 95% confidence interval [CI], 3.38-16.23, P < .001), negative pEGFR immunostaining with poor differentiation (OR, 0.39; 95% CI, 0.20-0.73, P = .004), and negative PTEN immunostaining with metastatic pelvic lymph nodes (OR, 0.51; 95% CI, 0.30-0.90, P = .019). In multivariate analysis, only pelvic lymph node metastasis (hazard ratio, 6.11; 95% CI, 3.46-10.77, P < .001) and poor differentiation (hazard ratio, 1.91; 95% CI, 1.12-3.26, P = .018) were related to disease-specific survival. In early-stage cervical cancer, loss of PTEN expression is associated with pelvic lymph node metastasis, suggesting PTEN to be one of the tumor suppressor genes affecting pelvic lymph node metastasis. However, expression of EGFR pathway components does not appear to have prognostic impact in surgically treated early-stage cervical cancer.

Expression of epidermal growth factor receptor (EGFR) and Ki67 in feline oral squamous cell carcinomas (FOSCC)

The aims of this study were to establish expression of epidermal growth factor receptor (EGFR) and Ki67 in 67 archived biopsy samples of feline oral squamous cell carcinomas (FOSCCs) and to establish if the expression of either markers was predictive of survival. Samples were immunohistochemically labelled for the two proteins and scored. Statistical analyses of data, including Kaplan-Meier survival curves, were performed. All samples expressed both markers although levels differed between samples. Median overall survival was 46 days and 1-year survival was 5%. There was no correlation between Ki67 and EGFR scores (Pearson's correlation coefficient, P = 0.861). Low cellular proliferation (low Ki67 score) was positively correlated with an overall longer survival (Log Rank, P = 0.02) and a trend towards better survival for the high EGFR group was observed (Log Rank, P = 0.076). Ki67 and EGFR immunostaining in FOSCC may be of value as biochemical markers for screening of biopsies from cases of FOSCC.