Low Epidermal Growth Factor Receptor Research Articles

Association between exposure to organophosphate flame retardants and epidermal growth factor receptor expression in lung cancer patients.

Organophosphate flame retardants (OPFRs) are extensively distributed in our environment, prompting concerns about potential health hazards, including lung injuries resulting from OPFR exposure. The present study recruited 125 lung cancer patients, assessing their exposure to 10 OPFR compounds through urine samples. The final analysis comprised 108 participants after excluding those lacking epidermal growth factor receptor (EGFR) status and those with chronic kidney disease. Demographic and clinical characteristics, as well as urinary OPFR concentrations, were compared based on OPFR detection. Spearman correlation was conducted to explore the relationship between OPFR compounds, while logistic regression was used to identify OPFR compounds associated with EGFR mutation. The study revealed widespread OPFR exposure among lung cancer patients, with an overall detection frequency of 99.07%. Tris(2-butoxyethyl) phosphate (TBEP) exhibited a strong correlation to its metabolite bis(2-butoxyethyl) phosphate (r = 0.88, p < 0.01). Patients with TBEP in their urine had higher percentage of wild-type EGFR and the detection of TBEP was associated with a reduced likelihood of mutant EGFR expression. OPFR exposure was prevalent in lung cancer patients, with TBEP detection identified as a factor with lower EGFR mutation expression. This study contributes to the understanding of OPFR exposure in lung cancer patients and underscores the significance of TBEP in evaluating EGFR mutation in this population.

EGF, TGF-α and Amphiregulin Differently Regulate Endometrium-Derived Mesenchymal Stromal/Stem Cells.

The prototypical receptor tyrosine kinase epidermal growth factor receptor (EGFR) is regulated by a set of its ligands, which determines the specificity of signaling and intracellular fate of the receptor. The EGFR signaling system is well characterized in immortalized cell lines such as HeLa derived from tumor tissues, but much less is known about EGFR function in untransformed multipotent stromal/stem cells (MSCs). We compared the effect of epidermal growth factor (EGF), transforming growth factor-α (TGF-α) and amphiregulin (AREG) on physiological responses in endometrial MSCs (enMSC) and HeLa cells. In addition, using Western blotting and confocal microscopy, we studied the internalization and degradation of EGFR stimulated by the three ligands in these cell lines. We demonstrated that unlike HeLa, EGF and TGF-α, but not AREG, stimulated enMSC proliferation and prevented decidual differentiation in an EGFR-dependent manner. In HeLa cells, EGF targeted EGFR for degradation, while TGF-α stimulated its recycling. Surprisingly, in enMSC, both ligands caused EGFR degradation. In both cell lines, AREG-EGFR internalization was not registered. In HeLa cells, EGFR was degraded within 2 h, restoring its level in 24 h, while in enMSC, degradation took more than 4-8 h, and the low EGFR level persisted for several days. This indicates that EGFR homeostasis in MSCs may differ significantly from that in immortalized cell lines.

EGFR expression and relapse in patients with melanoma receiving adjuvant PD-1-based immunotherapy.

e21566 Background: Since 2018, adjuvant immune checkpoint inhibitors (ICI) have been available for patients with resected stage III/IV melanoma. The Checkmate 238 and Keynote 054 studies showed a survival benefit in patients receiving adjuvant ICI. However, there is no validated biomarker to identify patients at high risk of relapse, despite receiving adjuvant therapy. Here we investigated resistance patterns to immune checkpoint inhibition in the adjuvant setting. Methods: In this cohort study, a discovery cohort of 30 patients from the Department of Dermatology, University Hospital Zürich, was used to evaluate resistance patterns to adjuvant ICI. A second cohort of 107 patients from the Department of Dermatology, University Hospital Tuebingen, was used to validate the findings. We measured epidermal growth factor receptor (EGFR) expression in primary tumor and metastatic tissue by immunohistochemistry and digital pathology using QuPath. The primary endpoint was relapse-free survival. Results: We included 137 patients with melanoma receiving adjuvant ICI: 63 (46%) were females, and 52 (38%) patients harbored a BRAFV600 mutation. The median follow-up was 45 and 39 months in the Zürich and Tuebingen cohorts, respectively (95% confidence interval (CI) 41.8-48.2 and 36.8-41.2, respectively). The two cohorts were homogenous in terms of patients' and tumor characteristics, except for the relapse rate, which was significantly higher in the Tuebingen cohort ( p&lt; 0.002). 71 (52%) therapy naïve in transit or lymph node metastasis and 23 (17%) primary tumors were available to evaluate EGFR expression by immunohistochemistry and digital pathology using QuPath. Surprisingly, in both cohorts, patients with high EGFR expression in metastatic tissue had a significantly higher relapse rate than patients with low EGFR expression ( p= 0.0004 and p= 0.0168 for the Zürich and Tuebingen cohorts, respectively). EGFR expression in primary tumors did not correlate with relapse-free survival ( p= 0.7286). Next-generation sequencing revealed that EGFR expression assessed by immunohistochemistry was not associated with the presence of EGFR mutations and/or amplifications. Conclusions: Currently, there are no validated biomarkers to identify patients with melanoma at high risk of recurrence, despite receiving adjuvant ICI. We found in two independent cohorts that EGFR expression in therapy naive metastatic tissue is positively associated with relapse in patients receiving adjuvant ICI. Our data identified EGFR as a prognostic biomarker that can easily be assessed by immunohistochemistry, allowing us to stratify patients for adjuvant ICI therapy according to their risk of relapse. Stratification according to EGFR expression should be considered in future clinical trials in the adjuvant setting.

Plumbagin binds to epidermal growth factor receptor and mitigate the effects of epidermal growth factor micro-environment in PANC-1 cells.

A sustained increase in the mortality of pancreatic cancer (PC) and sudden metastasis-related mortality is a cause for concern. Aberrant expression of epidermal growth factor (EGF) receptor (EGFR) is noted in several cases of PC metastasis. The present study is aimed at analyzing the expression of EGFR in PC and its relevance to the progression of PC. Despite the number of studies that have shown the benefits of plumbagin on PC cells, its role on cancer stem cells remains largely unknown. To this end, the study used an EGF micro-environment to make cancer stem cells in vitro and ascertained the role of plumbagin in mitigating the actions of EGF. The kaplan-meier (KM) plot indicated reduced overall survival (OS) analysis in PC patients with high EGFR than low EGFR expression. Plumbagin pre-treatment significantly prevented EGF-induced survival, epithelial-to-mesenchymal transition (EMT), clonogenesis, migration, matrix metalloproteinase -2 (MMP-2) gene expression and its secretion, and matrix protein hyaluron production in PANC-1 cells. The computational studies indicate the greater affinity of plumbagin with different domains of EGFR than gefitinib. Several hallmarks of resistance and migration due to EGF are effectively attenuated by plumbagin. Collectively, these results warrant investigating the actions of plumbagin in a pre-clinical study to substantiate these findings.

Clinicopathological Parameters and Immunohistochemical Expression of EGFR in Colorectal Carcinoma: A Cross-sectional Study

Introduction: Colorectal Carcinoma (CRC) is the third most common type of cancer worldwide and is one of the leading causes of cancer-related death. Adenocarcinoma is the most common type. Histopathological examination is necessary to determine the type and extent of the tumour, which is essential for patient management and prognosis. Molecular markers play a major role in CRC, among which Epidermal Growth Factor Receptor (EGFR) has prognostic significance. Aim: The aim of this study was to evaluate the immunohistochemical expression of EGFR in cases of colonic carcinoma and analyse its relationship with various histological and clinical parameters. Materials and Methods: An observational (cross-sectional) study was conducted in the Department of Pathology, Sree Mookambika Institute of Medical Sciences, Kulasekharam, Kanyakumari district, Tamil Nadu, India. Data from colonic carcinoma patients confirmed by Haematoxylin and Eosin (H&amp;E) staining were collected over a three-year period from January 2019 to December 2021. A total of 58 cases were included. The characteristics studied included age, sex, Carcinoembryonic Antigen (CEA) levels, tumour site, size, degree of histological differentiation (well, moderate, poor), TNM staging, and lymph node status. The EGFR score was obtained by multiplying the grade (% positive cells) by the intensity, and a composite score ranging from 0 to 9 was obtained. This score was used to define low EGFR expression (&lt;6) or high EGFR expression (&gt;6). Analysis was performed using the Chi-square test in Statistical Package for the Social Sciences (SPSS) version 20.0. Results: Among the 58 patients included in the study, the most common age group affected by CRC was 61 to 70 years (28 cases; 48.3%), with a mean age of 63.32±14.36 years. The most common histological variant was low-grade adenocarcinoma (47 cases; 81.03%). EGFR reactivity was positive in 50 patients (86.20%). EGFR overexpression was significantly associated with histopathological type (low-grade adenocarcinoma) and tumour stage, with p-values of 0.03 and 0.001, respectively. Conclusion: Immunohistochemical overexpression of EGFR in CRC is associated with histopathological type and tumour staging in this study. This overexpression is associated with poor prognosis and can be used as a predictive marker for patients who yield positive results with chemotherapy.

Postoperative Prognostic Predictors of Bile Duct Cancers: Clinical Analysis and Immunoassays of Tissue Microarrays.

Cholangiocarcinoma frequently recurs even after curative resection. Expression levels of proteins such as epidermal growth factor receptor (EGFR), Snail, epithelial cadherin (E-cadherin), and interleukin-6 (IL-6) examined by immunohistochemistry have been studied as potential prognostic factors for cholangiocarcinoma. The aim of this study was to investigate significant factors affecting the prognosis of resectable cholangiocarcinoma. Ninety-one patients who underwent surgical resection at Samsung Medical Center for cholangiocarcinoma from 1995 to 2013 were included in this study. Expression levels of E-cadherin, Snail, IL-6, membranous EGFR, and cytoplasmic EGFR were analyzed by immunohistochemistry using tissue microarray blocks made from surgical specimens. Patients with high levels of membranous EGFR in tissue microarrays had significantly shorter overall survival (OS) and disease-free survival (DFS): high membranous EGFR (score 0-2) 38.0 months versus low membranous EGFR (score 3) 14.4 months (p=0.008) and high membranous EGFR (score 0-2) 23.2 months versus low membranous EGFR (score 3) 6.1 months (p=0.004), respectively. On the other hand, E-cadherin, Snail, cytoplasmic EGFR, and IL-6 did not show significant association with OS or DFS. Patients with distant metastasis had significantly higher IL-6 levels than those with locoregional recurrence (p=0.01). This study showed that overexpression of membranous EGFR was significantly associated with shorter OS and DFS in surgically resected bile duct cancer patients. In addition, higher IL-6 expression was a predictive marker for recurrence in cholangiocarcinoma patients with distant organ metastasis after surgical resection.

Unique characteristics of G719X and S768I compound double mutations of epidermal growth factor receptor (EGFR) gene in lung cancer of coal-producing areas of East Yunnan in Southwestern China

BackgroundThe principal objective of this project was to investigate the Epidermal Growth Factor Receptor (EGFR) gene mutation characteristics of lung cancer patients, which can provide a molecular basis for explaining the clinicopathological features, epidemiology and use of targeted therapy in lung cancer patients in the coal-producing areas of East Yunnan.MethodologyWe collected 864 pathologically confirmed lung cancer patients’ specimens in First People’s Hospital of Qujing City of Yunnan Province from September 2016 to September 2021. We thereafter employed Next Generation Sequencing (NGS) technology to detect all exons present in the EGFR gene.ResultsThe overall mutation frequency of the EGFR gene was 47.22%. The frequency of EGFR gene mutations in the tissue, plasma, and cytology samples were found to be 53.40%, 23.33%, and 62.50%, respectively. Univariate analysis indicated that the coal-producing areas and Fuyuan county origin were significantly associated with relatively low EGFR gene mutation frequency. Female, non-smoking history, adenocarcinoma, non-brain metastasis, and tissue specimens were found to be related to high EGFR gene mutation frequency. Multivariate logistic regression analysis suggested the lung cancer patients in the central area of Qujing City, stage Ia, non-coal-producing areas, non-Fuyuan origin, and non-Xuanwei origin were more likely to develop EGFR gene mutations. The most common mutations were L858R point mutation (33.09%) and exon 19 deletion (19-del) (21.32%). Interestingly, the mutation frequency of G719X (p = 0.001) and G719X + S768I (p = 0.000) in the coal-producing areas were noted to be more significant than those in non-coal-producing regions.ConclusionThis findings of this study might be important in establishing the correlation between routine using NGS for EGFR gene mutation diagnosis and clinical practice in the lung cancer patients.

Economic Analysis of Tissue-First, Plasma-First, and Complementary NGS Approaches for Treatment-Naïve Metastatic Lung Adenocarcinoma.

BackgroundTo compare the testing costs and testing turnaround times of tissue-first, plasma-first, and complementary next-generation sequencing (NGS) approaches in patients with treatment-naïve metastatic lung adenocarcinoma.Materials and MethodsWe developed a decision tree model to compare three different approaches. Patients were entered into the model upon cancer diagnosis and those with both insufficient tissue specimens and negative liquid-based NGS were subjected to tissue re-biopsy. Actionable gene alterations with the U.S. Food and Drug Administration (FDA)-approved therapies included epidermal growth factor receptor (EGFR) mutation, anaplastic lymphoma kinase (ALK) gene rearrangement, ROS proto-oncogene 1 (ROS1) rearrangement, B-Raf proto-oncogene (BRAF) V600E mutation, rearranged during transfection (RET) gene rearrangement, mesenchymal-epithelial transition factor (MET) mutation, neurotrophic tyrosine receptor kinase (NTRK) gene rearrangement, K-Ras proto-oncogene (KRAS) G12C mutation, and human epidermal growth factor receptor 2 (HER2) mutation. Model outcomes were testing costs, testing turnaround times, and monetary losses taking both cost and time into consideration. We presented base-case results using probabilistic analysis. Stacked one-way and three-way sensitivity analyses were also performed.ResultsIn terms of testing costs, tissue-first approach incurred US$2,354($1,963–$2,779) and was the most cost-efficient strategy. Complementary approach testing turnaround time (days) of 12.7 (10.8 to 14.9) was found as the least time-consuming strategy. Tissue-first, complementary, and plasma-first approaches resulted in monetary losses in USD of $4,745 ($4,010–$5,480), $6,778 ($5,923–$7,600), and $7,006 ($6,047–$7,964) respectively, and identified the same percentage of patients with appropriate FDA-approved therapies. Costs for liquid-based NGS, EGFR mutation rates, and quantity of tissue specimens were the major determinants in minimizing monetary loss. Plasma-first approach would be the preferable strategy if its testing price was reduced in USD to $818, $1,343, and $1,869 for populations with EGFR mutation rates of 30%, 45%, and 60% respectively.ConclusionThe tissue-first approach is currently the best strategy in minimizing monetary loss. The complementary approach is an alternative for populations with a low EGFR mutation rate. The plasma-first approach becomes increasingly preferable as EGFR mutation rates gradually increase.

Association Between DCE-MRI Perfusion Histogram Parameters and EGFR and VEGF Expressions in Different Lauren Classifications of Advanced Gastric Cancer.

Objective: To investigate the correlations between dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) perfusion histogram parameters and vascular endothelial growth factor (VEGF) and epidermal growth factor receptor (EGFR) expressions in advanced gastric cancer (AGC). Methods: This retrospective study included 80 pathologically confirmed patients with AGC who underwent DCE-MRI before surgery from February 2017 to May 2021. The DCE-MRI perfusion histogram parameters were calculated by Omni Kinetics software in four quantitative parameter maps. Immunohistochemical methods were used to detect VEGF and EGFR expressions and calculate the immunohistochemical score. Results: VEGF expression was relatively lower in patients with intestinal-type AGC than those with diffuse-type AGC (p < 0.05). For VEGF, Receiver operating characteristics (ROC) curve analysis revealed that Quantile 90 of Ktrans, Meanvalue of Kep and Quantile 50 of Ve provided the perfect combination of sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for distinguishing high and low VEGF expression, For EGFR, Skewness of Ktrans, Energy of Kep and Entropy of Vp provided the perfect combination of sensitivity, specificity, PPV and NPV for distinguishing high and low EGFR expression. Ktrans (Quantile 90, Entropy) showed the strongest correlation with VEGF and EGFR in patients with intestinal-type AGC (r = 0.854 and r = 0.627, respectively); Ktrans (Mean value, Entropy) had the strongest correlation with VEGF and EGFR in patients with diffuse-type AGC (r = 0.635 and 0.656, respectively). Conclusion: DCE-MRI perfusion histogram parameters can serve as imaging biomarkers to reflect VEGF and EGFR expressions and estimate their difference in different Lauren classifications of AGC.

Noninvasive Evaluation of EGFR Expression of Digestive Tumors Using 99mTc-MAG3-Cet-F(ab')2-Based SPECT/CT Imaging.

Purpose This study is aimed at investigating the feasibility of cetuximab (Cet) F(ab′)2 fragment- (Cet-F(ab′)2-) based single photon emission tomography/computed tomography (SPECT/CT) for assessing the epidermal growth factor receptor (EGFR) expression in digestive tumor mouse models. Methods Cet-F(ab′)2 was synthesized using immunoglobulin G-degrading enzyme of Streptococcus pyogenes (IdeS) protease and purified with protein A beads. The product and its in vitro stability in normal saline and 1% bovine serum albumin were analyzed with sodium dodecyl sulfate–polyacrylamide gel electrophoresis. The EGFR expression in the human colon tumor cell line HT29 and the human stomach tumor cell line MGC803 were verified using western blotting and immunocytochemistry. Cet-F(ab′)2 was conjugated with 5(6)-carboxytetramethylrhodamine succinimidyl ester to demonstrate its binding ability to the MGC803 and HT29 cells. Cet-F(ab′)2 was conjugated with NHS-MAG3 for 99mTc radiolabeling. The best imaging time was determined using a biodistribution assay at 1, 4, 16, and 24 h after injection of the 99mTc-MAG3-Cet-F(ab′)2 tracer. Furthermore, 99mTc-MAG3-Cet-F(ab′)2 SPECT/CT was performed on MGC803 and HT29 tumor-bearing nude mice. Results HT29 cells had low EGFR expression while MGC803 cell exhibited the high EGFR expression. Cet-F(ab′)2 and intact cetuximab showed similar high binding ability to MGC803 cells but not to HT29 cells. Cet-F(ab′)2 and 99mTc-MAG3-Cet-F(ab′)2 showed excellent in vitro stability. The biodistribution assay showed that the target to nontarget ratio was the highest at 16 h (17.29 ± 5.72, n = 4) after tracer injection. The 99mTc-MAG3-Cet-F(ab′)2-based SPECT/CT imaging revealed rapid and sustained tracer uptake in MGC803 tumors rather than in HT29 tumors with high image contrast, which was consistent with the results in vitro. Conclusion SPECT/CT imaging using 99mTc-MAG3-Cet-F(ab′)2 enables the evaluation of the EGFR expression in murine EGFR-positive tumors, indicating the potential utility for noninvasive evaluation of the EGFR expression in tumors.

Study of Programmed Death Ligand 1 and EGFR/HER2 Expression in Non-Small-Cell Lung Carcinoma With a Clinicopathological Spectrum.

Non-small-cell lung carcinoma (NSCLC) is a disease characterized by the upregulation of programmed death ligand 1 (PD-L1) along with alterations in epidermal growth factor receptor (EGFR) and HER2-neu (HER2) amplification in addition to EGFR mutation. In the present study, the expression of PD-L1 and EGFR and HER2-neu in NSCLC was studied and their expression in relation to various clinicopathological parameters was analysed. We studied 49 core biopsy specimens of NSCLC for PD-L1, EGFR and HER2-neu expressions using immunohistochemistry. Scoring was based on the intensity and percentage of tumour cells expressing the immunomarkers. PD-L1, EGFR and HER2-neu expression was seen in 20.4%, 32.7% and 14.2% of NSCLC, respectively. The analysis showed no significant difference in PD-L1 expression in relation to any clinicopathological parameters. Low or negative EGFR expression was significantly associated with positive lymph node status (P=0.04). HER2-neu expression showed a significant difference in relation to tumour histology (adenocarcinoma; P=0.01). Also, there was no difference noted with PD-L1 expression in relation to EGFR and HER2-neu expression. As our study has a small number of cases, the validation of the predictive and prognostic value of these markers in lung cancer patients requires further studies.

Occurrence of Epidermal Growth Factor Receptor Expression in Squamous Cell Carcinoma of Oral Cavity and Adjacent Sites: A Retrospective Observational Study

AbstractIntroduction Oral cavity squamous cell carcinomas (OCSCCs) are one of the most common malignancies encountered. They have diverse clinicopathologic profiles. Epidermal growth factor receptor (EGFR) is an important marker of OCSCC for diagnosis, prognosis, and therapy.Objective The study aimed to evaluate the distribution of clinicopathological parameters in cases of squamous cell carcinoma (SCC) of the oral cavity and adjacent sites and their EGFR expression. An attempt was made to correlate EGFR scores with different parameters.Materials and Methods An observational retrospective study was undertaken for 1 year. Patients with histologically proven SCC of the oral cavity and adjacent sites were included. Clinicopathologic and immunohistochemical features of each case were analyzed.Results A total of 59 cases of SCC were included of which 41 (69%) were males. The mean age of the patients was 56.4 ± 10.3 years. The most common location of the tumors was oral cavity (31, 53%) followed by larynx (10, 16%). Most cases were moderately differentiated tumors (31, 53%). Immunohistochemical analysis showed low EGFR score in 7 (11.9%) cases, intermediate in 6 (10.1%), and high in 46 (78%) cases. Association between gender of patients and EGFR score was statistically significant (p = 0.000159). Most lesions of the oral cavity (31 cases, 53%) had a high EGFR score (23 cases, 74.2%). A statistically significant correlation was found between tumor grade and EGFR score (p = 0.03338).Conclusion This study from eastern region of India reveals unique characteristics of EGFR expression in SCC of the oral cavity and adjacent sites.

Honokiol Prevents Non-Alcoholic Steatohepatitis-Induced Liver Cancer via EGFR Degradation through the Glucocorticoid Receptor-MIG6 Axis.

Simple SummaryNon-alcoholic fatty liver disease (NAFLD) is a major health problem globally linked with the growing prevalence of metabolic syndrome. A subset of patients with NAFLD progress to non-alcoholic steatohepatitis (NASH), which increases the risk of hepatocellular carcinoma (HCC). However, the mechanisms responsible for the progression to HCC are unclear, and no preventative modalities have been developed. To address this issue, the present study used the natural compound honokiol to clarify the mechanism of this process. The results illustrated that epidermal growth factor receptor (EGFR) was upregulated in mice with NASH, and treatment with honokiol inhibited EGFR and the progression to HCC. Further analysis illustrated that honokiol increased glucocorticoid receptor (GR) nuclear translocation and mitogen-inducible gene 6 (MIG6)/ERBB receptor feedback inhibitor 1 (ERRFI1) expression, thereby promoting EGFR degradation. These findings were confirmed in tissues from patients with NASH and HCC.Non-alcoholic steatohepatitis (NASH) has become a serious public health problem associated with metabolic syndrome. The mechanisms by which NASH induces hepatocellular carcinoma (HCC) remain unknown. There are no approved drugs for treating NASH or preventing NASH-induced HCC. We used a genetic mouse model in which HCC was induced via high-fat diet feeding. This mouse model strongly resembles human NASH-induced HCC. The natural product honokiol (HNK) was tested for its preventative effects against NASH progression to HCC. Then, to clarify the mechanisms underlying HCC development, human HCC cells were treated with HNK. Human clinical specimens were also analyzed to explore this study’s clinical relevance. We found that epidermal growth factor receptor (EGFR) signaling was hyperactivated in the livers of mice with NASH and human HCC specimens. Inhibition of EGFR signaling by HNK drastically attenuated HCC development in the mouse model. Mechanistically, HNK accelerated the nuclear translocation of glucocorticoid receptor (GR) and promoted mitogen-inducible gene 6 (MIG6)/ERBB receptor feedback inhibitor 1 (ERRFI1) expression, leading to EGFR degradation and thereby resulting in robust tumor suppression. In human samples, EGFR-positive HCC tissues and their corresponding non-tumor tissues exhibited decreased ERRFI1 mRNA expression. Additionally, GR-positive non-tumor liver tissues displayed lower EGFR expression. Livers from patients with advanced NASH exhibited decreased ERRFI1 expression. EGFR degradation or inactivation represents a novel approach for NASH–HCC treatment and prevention, and the GR–MIG6 axis is a newly defined target that can be activated by HNK and related compounds.

PL01.06 Molecular Epidemiology of Asian Lung Cancer

Lung adenocarcinoma (LADC), the most frequent histological type of lung cancer, develops in both ever- and never-smokers, and has two distinct characteristics in Asian populations. First, the proportion of never-smoking patients is considerably higher than that among individuals of European descent (approximately 40% vs 10%), and the rates of development and death from lung cancer in never-smokers are significantly higher in Asians than those in individuals of European descent. Second, in Asian individuals LADC frequently (in approximately 50% of cases) carries oncogenic mutations of the epidermal growth factor receptor (EGFR) gene, in contrast to lower EGFR mutation rates (approximately 10%) in European/US patients. In Asian patients, EGFR mutation frequently occurs in both never- (60%) and ever- (40%) smokers, while it occurs almost exclusively in European/US ever-smokers. Notably, EGFR-mutated LADC does not respond well to immune checkpoint blockade therapy due to its non-inflamed (immune-cold) features, including low infiltration of CD4+ and CD8+ T cells. Therefore, it is highly likely that there are specific risk factors, independent from smoking, that promote LADC development in Asians and have immunogenic effects influencing tumour characteristics. By conducting genome-wide association study, we demonstrated that HLA loci influence lung adenocarcinoma risk independently from smoking and that the association of HLA-class II, but not class I, loci is more prominent for lung adenocarcinomas with EGFR gene mutations than those without; the HLA-DPB1 Asp57 and 76Val alleles are associated with elevated risk for EGFR-mutated lung adenocarcinoma. HLA variants might influence lung adenocarcinoma risk by modulating anti-tumour immunity.

Epidermal growth factor receptor intron 1 polymorphism and microsatellite instability in sporadic colorectal cancer.

Epidermal growth factor receptor (EGFR) expression is commonly upregulated in sporadic colorectal cancer (CRC) and its high expression is associated with poor prognosis in patients with CRC. CA-SSR1 is a dinucleotide CA repeat of the EGFR gene that can modulate EGFR transcription and is a potential target of the mismatch repair machinery in tumours with microsatellite instability (MSI). In the present study, 160 sporadic colon cancer samples were analysed for EGFR CA-SSR1 polymorphism and MSI status. Additionally, EGFR mRNA and protein expression levels in the tumour centre and in the invasive tumour front, compared with those in adjacent normal tissue samples, were evaluated in 80 tumour samples. An inverse association was identified between EGFR mRNA levels and the sum of repeats in both alleles of the CA-SSR1 polymorphism in normal tissues. Changes in CA-SSR1 were detected in the tumour centre as well as in the invasive tumour front and metastases in all MSI high (MSI-H) tumours. Analysis of EGFR expression at the mRNA and protein levels according to MSI status revealed lower EGFR mRNA and protein expression in MSI-H tumours than microsatellite-stable (MSS) tumours. Furthermore, higher EGFR levels in the invasive tumour front compared with in the tumour centre in MSS tumours were identified, suggesting a role of EGFR in tumour progression and higher invasive potential of MSS than MSI-H tumours.

Enhanced Caspase-Mediated Abrogation of Autophagy by Temozolomide-Loaded and Panitumumab-Conjugated Poly(lactic-co-glycolic acid) Nanoparticles in Epidermal Growth Factor Receptor Overexpressing Glioblastoma Cells.

The mechanism of cell death has attracted a great deal of research interest in the design of antitumor therapy in recent days. Several attempts have been carried out in this direction and in our study also, we studied this phenomenon with the design of panitumumab (PmAb)-conjugated and temozolomide (TMZ)-loaded poly(lactic-co-glycolic acid) nanoparticles (PLGA-NPs), termed PmAb-TMZ-PLGA-NPs. First, PmAb was functionalized on the surface of TMZ-PLGA-NPs using ethyl(dimethylaminopropyl)carbodiimide (EDC)-N-hydroxysuccinimide (NHS) chemistry. Targeted PLGA-NPs significantly enhanced the cellular uptake of nanoparticles in the U-87 MG cell line as a result of the high epidermal growth factor receptor (EGFR) expression, compared to the LN229 cell line. Our study demonstrated that following the treatment of PmAb-TMZ-PLGA-NPs, a more pronounced anticancer effect was noticed in comparison with free TMZ and TMZ-PLGA-NPs. Further, a more pronounced cytotoxic effect of PmAb-TMZ-PLGA-NPs was observed in the high EGFR-overexpressed glioblastoma multiforme (GBM) model (U-87 MG) cell line compared to the low EGFR GBM model (LN229). Our study demonstrated that the treatment of PmAb-TMZ-PLGA-NPs in GBM tried to adopt the autophagic pathway of the cell survival mechanism with the elevated level of autophagic marker (Beclin-1 and LC3B) at 24 h time point, thereby suppressing the expression of caspase-9 and PARP. However, at the 48 h time point, the elevated expression of caspase-9 and PARP with the downregulation of Beclin-1 and LC3B, following the treatment of PmAb-TMZ-PLGA-NPs in the GBM model, suggested that apoptotic cell death was superior over autophagic cell survival. It was also noteworthy the activation of caspase-9 was correlated with the continuous overproduction of reactive oxygen species up to a 48 h time point after the treatment of PmAb-TMZ-PLGA-NPs. This result sheds light on the biological effect of targeted chemotherapy and illustrates that PmAb-TMZ-PLGA-NPs could be applied for EGFR-overexpressed different cancer models.

Epidermal growth factor receptor as a molecular determinant of glioblastoma response to dopamine receptor D2 inhibitors.

There are ongoing clinical trials exploring the efficacy of dopamine receptor D2 (DRD2) inhibition against glioblastomas, the most common primary brain tumor. Here we examine potential molecular determinants of this efficacy. The Cancer Genome Atlas glioblastoma database and other published mRNA profiles were used to analyze the DRD2 and epidermal growth factor receptor (EGFR) expression pattern. In vitro and in vivo responses to DRD2 inhibitors were determined using patient-derived xenograft (PDX) glioblastoma models. Immunohistochemical studies were performed on clinically annotated glioblastoma samples derived from patients treated with ONC201. Analysis of clinical glioblastoma specimens derived from independent patient cohorts revealed an inverse correlation between EGFR and DRD2 mRNA expression, with implication that signaling mediated by these proteins shares overlapping functions. In independent panels of PDX glioblastoma lines, high EGFR expression was associated with poor in vitro and in vivo response to DRD2 inhibitors, including haloperidol and ONC201. Moreover, ectopic expression of a constitutively active EGFR, variant (v)III, suppressed glioblastoma sensitivity to ONC201. DRD2 expression positively correlated with expression of rate-limiting enzymes for dopamine synthesis as well as dopamine secretion, suggesting contribution of autocrine DRD2 signaling. Analysis of specimens from patients treated with ONC201 (n = 15) showed an inverse correlation between the intensity of EGFR staining and clinical response. The median overall survival for patients with high and low EGFR staining was 162 and 373 days, respectively (0.037). High EGFR expression is a determinant of poor glioblastoma response to DRD2. This finding should inform future clinical trial designs.

Epidermal growth factor receptor expression as a molecular determinant of glioblastoma response to the dopamine receptor D2 antagonist, ONC201.

e14552 Background: Durable response in glioblastoma patients have been reported in phase I/II clinical trials for the blood-brain penetrant dopamine receptor D2 (DRD2) antagonist, ONC201. Here we examine potential molecular determinants of response to DRD2 inhibition. Methods: The Cancer Genome Atlas (TCGA) glioblastoma database and other published mRNA profiles were used to analyze the DRD2 expression pattern. In vitro and in vivo responses to ONC201 were determined using patient derived xenograft glioblastoma models. Immunohistochemical studies were performed on clinically annotated glioblastoma samples derived from phase I/II clinical trials involving ONC201. Results: For the majority of clinical glioblastoma specimens in both the TCGA and non-TCGA dataset, epidermal growth factor receptor (EGFR) expression was inversely correlated with DRD2. This observation was recapitulated in a panel of patient-derived glioblastoma lines. In this panel of DRD2 expressing lines, high EGFR expression was associated with poor response to ONC201 in vitro and in vivo. Moreover, ectopic expression of EGFR reduced DRD2 expression and ONC201 sensitivity, suggesting functional redundancy between DRD2 and EGFR. In cell lines and clinical glioblastoma samples, DRD2 expression closely associated with the expression of rate-limiting enzymes for dopamine synthesis, suggesting dependency of a subset of glioblastomas on autocrine DRD2 signaling. Analysis of specimens from patients treated with ONC201 (n = 15) showed an inverse correlation between the intensity of EGFR staining and clinical response. The median overall survival for patients with high and low EGFR staining was 162 and 373 days, respectively (p = 0.037). All patients who exhibited progression free survival beyond 200 days showed low to no EGFR expression. Conclusions: Our results suggest EGFR expression as a determinant of response to ONC201 in glioblastoma patients and should inform the design of future clinical trials.

The role of epidermal growth factor receptor (EGFR) in the efficacy of neoadjuvant chemotherapy in triple-negative breast cancer patients

Background. Identification of predictive molecular markers of triple-negative breast cancer (TNBC) will enable the evaluation of the efficacy of neoadjuvant chemotherapy (NACT) and define optimum approaches for the prognosis of the disease course in TNBC patients. The aim of the study was to examine the correlation between the expression of the epidermal growth factor receptor (EGFR), its gene’s polymorphic variants and the neoadjuvant chemotherapy (NACT) efficacy in triple-negative breast cancer (TNBC) patients. Materials and methods. The study included 70 patients with triple-negative breast cancer, who had received 2-4 cycles of FAC and CAX regimens. The efficacy of the neoadjuvant chemotherapy was assessed according to the RECIST scale. The EGFR expression level in tumors before and after the NACT was evaluated with the help of immunohistochemistry. Genotypes for EGFR (rs2227983 and rs1468727) were detected by a real-time PCR. Results. It was found that NCT significantly decreases the EGFR expression level in the tumor ( p = 0.000). The research associates the objective clinical response as well as the pathological complete response with the low EGFR expression level ( p = 0.007 and p = 0.000 respectively). Patients carrying the EGFR CC mutant genotype of rs1468727 did not achieve a pathological complete response ( p = 0.042). In addition, patients with EGFRCC mutant genotype are more likely to have tumors with a high EGFR expression compared to EGFRTT wild-type genotype patients ( p = 0.047). Conclusion . The EGFR expression level in tumor tissue and the polymorphic variants of its gene in the rs1468727 locus can be considered as potential molecular markers with predictive significance in relation to the NACT efficacy in triple-negative breast cancer patients.

Dual-Receptor-Targeted (DRT) Radiation Nanomedicine Labeled with 177Lu Is More Potent for Killing Human Breast Cancer Cells That Coexpress HER2 and EGFR Than Single-Receptor-Targeted (SRT) Radiation Nanomedicines.

Resistance to HER2-targeted therapies in breast cancer (BC) is associated in some cases with an increased expression of epidermal growth factor receptors (EGFR). We describe a dual-receptor-targeted (DRT) radiation nanomedicine for local intratumoral (i.t.) treatment of BC composed of 15 nm sized gold nanoparticles (AuNPs) modified with trastuzumab (TmAb) to target HER2 and panitumumab (PmAb) to target EGFR. The AuNPs were modified with poly(ethylene glycol) (PEG3k) linked to 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) chelators to complex the β-particle emitter, 177Lu. Our aim was to compare the properties of these DRT-AuNP-177Lu with single-receptor-targeted (SRT)-TmAb-AuNP-177Lu or PmAb-AuNP-177Lu or nontargeted (NT)-AuNP-177Lu using human BC cells that expressed HER2, EGFR, or both receptors. To construct these radiation nanomedicines, PEG5K was linked to TmAb or PmAb, while PEG3k was linked to DOTA. These polymers were conjugated to AuNP via two Au-thiol bonds using a terminal lipoic acid (LA) group on the polymers. NT-AuNP-177Lu were constructed without modification with TmAb or PmAb. MDA-MB-231-H2N, MDA-MB-468, and BT-474 human BC cells were designated as HER2mod/EGFRmod, EGFRhigh/HER2neg, and HER2high/EGFRlow, respectively, based on the expression of these receptors. Specific binding to HER2 and/or EGFR was assessed by incubating BC cells with DRT-AuNP-177Lu or TmAb-AuNP-177Lu or PmAb-AuNP-177Lu, or NT-AuNP-177Lu in the absence or presence of an excess of TmAb or PmAb or both competitors. Binding and internalization of AuNP by BC cells were assessed by dark-field microscopy. Cell fractionation studies were conducted to quantify AuNP-177Lu bound and internalized. The cytotoxicity of DRT-AuNP-177Lu was determined in clonogenic survival (CS) assays after an exposure of 5 × 105 BC cells to 3 MBq (1.4 × 1012 AuNP) for 16 h and then seeding and culturing the cells for 7-15 days. CS was compared to exposure to TmAb-AuNP-177Lu and PmAb-AuNP-177Lu or NT-AuNP-177Lu. The absorbed doses to the nucleus in these CS assays were estimated. DRT-AuNP-177Lu were specifically bound by BC cells that expressed HER2 or EGFR or both receptors. In contrast, SRT-TmAb-AuNP-177Lu and PmAb-AuNP-177Lu were bound and internalized only by BC cells that expressed HER2 or EGFR, respectively. NT-AuNP-177Lu exhibited very low binding to BC cells. DRT-AuNP-177Lu and SRT-TmAb-AuNP-177Lu or PmAb-AuNP-177Lu were internalized by BC cells in accordance with the receptor expression. Importantly, DRT-AuNP-177Lu were more potent in vitro than PmAb-AuNP-177Lu for killing MDA-MB-231-H2N cells that coexpress HER2 and EGFR (CS = 18.8 ± 1.0 vs 51.5 ± 10.4%; P = 0.006). Furthermore, DRT-AuNP-177Lu were more potent for killing BT-474 cells with high HER2 but low EGFR expression than TmAb-AuNP-177Lu (CS = 8.9 ± 3.3 vs 20.7 ± 2.4%; P = 0.007) or PmAb-AuNP-177Lu (CS = 63.9 ± 1.7%; P < 0.0001). Even for MDA-MB-468 cells that overexpress EGFR but have negligible HER2, DRT-AuNP-177Lu were more potent for cell killing than PmAb-AuNP-177Lu (CS = 3.2 ± 3.0 vs 7.5 ± 1.8%; P = 0.001) or TmAb-AuNP-177Lu (63.2 ± 3.2%; P = 0.0002). All targeted forms of AuNP-177Lu were more cytotoxic to BC cells than those of NT-AuNP-177Lu. High absorbed doses (36-119 Gy) were deposited in the nucleus of BC cells by DRT-AuNP-177Lu. We conclude that a DRT radiation nanomedicine is more potent for killing BC cells that coexpress HER2 and EGFR than SRT radiation nanomedicines. These results are promising for further evaluation of these DRT-AuNP-177Lu in vivo for the local radiation treatment of human BC tumors that coexpress HER2 and EGFR in mice following i.t. injection, especially tumors that are resistant to HER2-targeted therapies.