Epidermal Growth Factor Receptor Gene Polymorphisms Research Articles

Investigating the Association between rs712829 Polymorphism of EGFR Gene with Lung Cancer as a Predictive Marker in Iranian Population

Background and Objectives Lung cancer is the leading cause of cancer death globally. The epidermal growth factor receptor (EGFR) plays an important role in cell proliferation and signaling. In this study, we examined the association between EGFR (rs712829) gene polymorphism and lung cancer risk among the Iranian population. Subjects and Methods A total of 100 patients with primary lung cancer and 100 matched healthy controls were recruited into this study. EGFR rs712829 single nucleotide polymorphism (SNP) were genotyped by PCR-RFLP techniques for this association with lung cancer risk. Results A significant association was observed between the GG genotype (P= 0.039, OR= 5.500, CI=95%; 1.710- 11.921) and also G (P= 0.001, OR= 2.967, CI=95%; 1.557- 5.691) allele of rs712829 SNP with lung cancer risk, this was while the TT genotype and T allele of this polymorphism showed a protective role against risk of lung cancer. Conclusion In conclusion, EGFR rs712829 was associated with a risk of lung cancer among Iranians. More studies in other Iranian populations are required to confirm the present findings.

Investigating the importance of EGFR (− 216G/T), Exo1 (K589E) and LEP (− 2548G/A) gene polymorphisms with risk of lung cancer as potential diagnostic biomarker in Iranian population

BackgroundIn Iran, lung cancer is the third most common type of cancer and its prevalence is increasing rapidly. Identification informative genetic polymorphisms in cancer causing genes including epidermal growth factor receptor (EGFR) as key gene in control of cellular proliferation via intrinsic tyrosine/kinase activity, exonuclease 1 (EXO1) as one of the upregulated gene in different human malignancies and leptin (LEP) participate in carcinogenesis in lung cancer appears to be used as potential genetic markers for predicting lung cancer risk. There is no study about investigate association of the EGFR (− 216G/T), Exo1 (K589E) and LEP (− 2548G/A) gene polymorphisms with risk of lung cancer in Iranian population. The aim of this study was investigating the association of EGFR (− 216G/T), Exo1 (K589E) and LEP (− 2548G/A) gene polymorphisms with risk of lung cancer as a potentially diagnostic biomarker in Iranian population.MethodsIn this case–control study, A total of 100 patients with lung cancer and 100 age and gender-matched healthy controls were recruited into this study and the association between EGFR (− 216G/T), Exo1 (K589E) and LEP (− 2548G/A) gene polymorphisms with the risk of lung cancer was investigated by using PCR–RFLP technique and bioinformatics approach.ResultsThe rs712829 of EGFR gene show that a significant statistical difference between G allele and risk of lung cancer (P = 0.001, OR = 2.976, CI = 95%, 1.557–5.691), in contrast, the T allele and TT genotype show a protective role against the risk of lung cancer. Result of in silico analysis indicated that the rs712829 alter splicing and promoter regulation of EGFR gene and associated with the risk of lung cancer. PCR–RFLP result for rs1047840 of Exo1 gene showed that the AA genotype and A allele of this polymorphism associated with risk of lung cancer, whereas the GG genotype show a protective effect against the risk of lung cancer (P = 0.004, OR = 5.391, CI = 95%, 1.690–17.200). On the other hand, in silico analysis showed that the existence of rs1047840 in Exo1 gene influence lung cancer susceptibility. For rs7799039 of LEP gene, PCR–RFLP analysis showed that, there is no significant association between this polymorphism and the risk of lung cancer.ConclusionThe rs712829 of EGFR gene and rs1047840 of Exo1 are associated with risk of lung cancer among Iranian population and can be used as a potentially candidate biomarker for early detection and primary prevention.

Significance of EGFR investigation in odontogenic keratocyst: a narrative review.

The recent classification of odontogenic keratocysts (OKSs) recognized them as benign neoplasms, although previous findings have revealed their aggressive nature. Immunohistochemical and molecular analyses have investigated OKSs, but the role of epidermal growth factor receptor (EGFR) has not been fully investigated, despite the importance of this oncogene in the process of carcinogenesis in tumors of epithelial origin. The EGFR protein is usually overexpressed, and the EGFR gene is mutated or amplified. This brief review aims to emphasize the importance of EGFR detection in these types of cysts. It was revealed that the majority of the studies examined EGFR protein expressionusing immunohistochemical methods; however, considering EGFR gene variants, mutations were less exploredin the previous periodfrom 1992 to 2023. Although EGFR gene polymorphisms are clinically important, they were not identified in the present study. In light of the current significance of EGFR variants, it would be beneficial to examine them in odontogenic lesions. This would enable resolving of discrepancies about their nature, and potentially enhance classificationsOKCs in the future.

Epidermal Growth Factor Receptor (EGFR) Gene Polymorphism May be a Modifier for Cadmium Kidney Toxicity.

The results of many studies indicate that cadmium (Cd) exposure is harmful to humans, with the proximal tubule of the kidney being the main target of Cd accumulation and toxicity. Studies have also shown that Cd has the effect of activating the pathway of epidermal growth factor receptor (EGFR) signaling and cell growth. The EGFR is a family of transmembrane receptors, which are widely expressed in the human kidney. The aim of this study was to investigate the kidney function estimated glomerular filtration rate (eGFR), and its relationship with plasma Cd level and EGFR gene polymorphism. Using data from Academia Sinica Taiwan biobank, 489 subjects aged 30–70 years were analyzed. The demographic characteristics was determined from questionnaires, and biological sampling of urine and blood was determined from physical examination. Kidney function was assessed by the eGFR with CKD-EPI formula. Plasma Cd (ug/L) was measured by inductively coupled plasma mass spectrometry. A total of 97 single-nucleotide polymorphisms (SNPs) were identified in the EGFR on the Taiwan biobank chip, however 4 SNPs did not pass the quality control. Multiple regression analyses were performed to achieve the study aim. The mean (±SD) plasma Cd level of the study subjects was 0.02 (±0.008) ug/L. After adjusting for confounding variables, rs13244925 AA, rs6948867 AA, rs35891645 TT and rs6593214 AA types had higher eGFR (4.89 mL/min/1.73 m2 (p = 0.035), 5.54 mL/min/1.73 m2 (p = 0.03), 4.96 mL/min/1.73 m2 (p = 0.048) and 5.16 mL/min/1.73 m2 (p = 0.048), respectively). Plasma cadmium and rs845555 had an interactive effect on eGFR. In conclusion, EGFR polymorphisms could be modifiers of Cd kidney toxicity, in which rs13244925 AA, rs6948867 AA, rs35891645 TT and rs6593214 AA may be protective, and Cd interacting with rs845555 may affect kidney function.

The Relationship between Metabolic Syndrome and Plasma Metals Modified by EGFR and TNF-α Gene Polymorphisms

With the escalating global prevalence of metabolic syndrome (MetS), it is crucial to detect the high-risk population early and to prevent chronic diseases. Exposure to various metals has been indicated to promote MetS, but the findings were controversial, and the effect of genetic modification was not considered. Epidermal growth factor receptor (EGFR) was proposed to be involved in the pathway of metabolic disorders, and tumor necrotic factor-α (TNF-α) was regarded as an early inflammatory biomarker for MetS. This research aimed to analyze the impact of EGFR and TNF-α gene polymorphisms on the prevalence of MetS under environmental or occupational exposure to metals. We gathered data from 376 metal industrial workers and 639 non-metal workers, including physical parameters, biochemical data, and plasma concentrations of six metals. According to the genomic database of Taiwan Biobank, 23 single nucleotide polymorphisms (SNPs) on EGFR gene and 6 SNPs on TNF-α gene were incorporated in our research. We applied multivariable logistic regression to analyze the probability of MetS with various SNPs and metals. Our study revealed some susceptible and protective EGFR and TNF-α genotypes under excessive exposure to cobalt, zinc, selenium, and lead. Thus, we remind the high-risk population of taking measures to prevent MetS.

The Association of Renal Function and Plasma Metals Modified by EGFR and TNF-α Gene Polymorphisms in Metal Industrial Workers and General Population.

Exposure to metals may be associated with renal function impairment, but the effect modified by genetic polymorphisms was not considered in most studies. Epidermal growth factor receptor (EGFR) and tumor necrotic factor-α (TNF-α) play important roles in renal hemodynamics, and they have been reported to be associated with some renal diseases. The aim of our research is to explore whether genetic variations in EGFR and TNF-α have influence on renal function under exposure to various metals. This cross-sectional study consisted of 376 metal industrial workers, 396 participants of Taiwan Biobank, and 231 volunteers of health examinations. We identified 23 single nucleotide polymorphisms (SNPs) on the EGFR gene and 6 SNPs on the TNF-α gene, and we also measured their plasma concentration of cobalt, copper, zinc, selenium, arsenic, and lead. Multiple regression analysis was applied to investigate the association between various SNPs, metals, and renal function. Our results revealed some protective and susceptible genotypes under occupational or environmental exposure to metals. The individuals carrying EGFR rs2280653 GG might have declined renal function under excessive exposure to selenium, and those with EGFR rs3823585 CC, rs12671550 CC, and rs4947986 GG genotypes might be susceptible to lead nephrotoxicity. We suggest the high-risk population to prevent renal diseases.

The impact of EGFR gene polymorphisms on the response and toxicity derived from neoadjuvant chemotherapy for breast cancer.

Neoadjuvant chemotherapy is usually used for treating locally advanced breast cancer. However, not all patients achieve pathologic complete response (pCR). In this study, we selected two epidermal growth factor receptor (EGFR) single nucleotide polymorphism (SNP) sites, rs1468727 and rs845552, to investigate the association between the genotypes and the response and toxicity derived from neoadjuvant chemotherapy for breast cancer. All participants took part in clinical trial SHPD001 and SHPD002. For univariate analyses, the association between SNP and pCR or toxicity was analyzed by Chi-square or Fisher's exact test. For multivariate analyses, logistic regression was used instead. In all, one hundred and eighteen patients were enrolled. We found that the frequency of AA genotype in rs845552 was higher than that of other genotypes in HER2-positive breast cancer (AA vs. AG, P=0.039; AA vs. GG, P=0.005; AA vs. AG+GG, P=0.009). Multivariate logistic regression analyses showed that pCR was more difficult to be achieved in patients with a CT genotype in rs1468727 compared to those with a CC+TT genotype (OR =0.288, 95% CI: 0.109-0.762, P=0.012) or a CC genotype (OR =0.254, 95% CI: 0.076-0.849, P=0.026). Moreover, we demonstrated that both rs1468727 and rs845552 were associated with toxicity that results in complications such as increased total bilirubin, skin rash, peripheral neuropathy, and alopecia (P<0.05). Our study reported for the first time, that in treating breast cancer with neoadjuvant chemotherapy, EGFR SNP rs1468727 is associated with treatment response, and that both rs1468727 and rs845552 are related to treatment-derived toxicity. In addition, we also found that rs845552 may be related to the status of HER2 in breast cancer.

The investigation of the amounts and expressions of epidermal growth factor, epidermal growth factor receptor, and epidermal growth factor receptor gene polymorphisms in acne vulgaris.

Epidermal growth factor receptor inhibitors (EGFRI) used in cancer chemotherapy cause acneiform folliculitis in 70%-100% of patients in a dose-dependent manner. Acneiform folliculitis is considered to be caused by an inflammatory process due to follicular hyperkeratosis and subsequently a set of changes both in epidermis and hair follicles as a result of epidermal growth factor receptor (EGFR) blockade. Both acne vulgaris and acneiform folliculitis due to EGFRIs show similar changes in the pilosebaceous unit. Furthermore, in both groups of patients, topical application of recombinant human epidermal growth factor (EGF) has been reported to improve the disease. In this study, it was aimed to investigate the role of EGF and EGFR amount, expression, and EGFR gene polymorphisms in the etiopathogenesis of acne vulgaris. 156 acne vulgaris patients, within 18-25years of age, who had 15 or more inflammatory acne lesions on dermatologic evaluation were included in this study. The absence of any known systemic or genetic disease or cancer and any systemic or topical treatment for the last 1month were prerequisites. In the control group, 154 volunteers in the same age range who were examined at the outpatient clinic with diagnoses of melanocytic nevus, ephelid, cherry angioma, and callus and who had no more than 3 inflammatory acne lesions were recruited. The amounts of EGF and EGFR were determined by sandwich ELISA, expressions of EGF and EGFR by reverse transcriptase polymerase chain reaction; EGFR polymorphisms were examined by restriction enzyme digestion, Sanger, and high-resolution melting methods. The patient and control groups were compared in terms of EGFR gene polymorphisms in addition to the amount and expressions of EGF and EGFR. The amount of EGF in the serum was found to be significantly higher in the acne group. (P=.0012). There was no significant difference in other parameters studied. The results of our study showed a significant increase in the amount of EGF in the acne group. Though EGF may be incriminated in the etiopathogenesis of AV, the most likely explanation about its role may be controlling inflammation from the very first stage.

The Association between Epidermal Growth Factor Receptor (EGFR) Gene Polymorphisms and Lung Cancer Risk

Lung cancer is the leading cause of cancer death globally. The epidermal growth factor receptor (EGFR) plays an important role in cell proliferation and signaling. In this study, we examined the association between EGFR gene polymorphisms and lung cancer risk among the Jordanian population. A total of 129 patients with primary lung cancer and 129 matched healthy controls were recruited into this study. EGFR rs712829, rs712830, rs2072454, and rs11543848 single nucleotide polymorphisms (SNPs) were genotyped to test for their association with lung cancer risk. A significant association was observed between the rs712829 SNP and lung cancer risk (p &lt; 0.05) where the GG + GT genotypes were higher in lung cancer patients when compared to controls. In addition, no association was detected between rs712830, rs2072454, and rs11543848 SNPs and lung cancer risk. When patients were stratified according to the lung cancer type, a significant association was detected between both rs712829 and rs2072454 and adenocarcinoma lung cancer (p &lt; 0.05). Haplotype analysis of all four SNPs showed a significant association between the TCCG haplotype and both lung cancer and the adenocarcinoma subtype (p &lt; 0.001). In conclusion, EGFR rs712829, rs2072454 SNPs, and TCCG haplotypes are associated with a risk of lung cancer among Jordanians. Since genetic associations are affected by the genetic background of populations, more studies in other Arab populations are required to confirm the present findings.Support or Funding InformationThe study was supported by funding provided by the Ministry of Higher Education—Scientific Research Fund (SRF) grant number JUST‐1‐2016. Genotypes/Allele Pattern Patients Controls p‐Value For rs712829 GG 12 (28%) 29 (22%) 0.020 TT 4 (9%) 35 (27%) GT 27 (63%) 65 (50%) For rs712830 CC 41 (95%) 121 (94%) 0.670 CA 2 (5%) 8 (6%) For rs2072454 CC 6 (14%) 15 (12%) 0.027 TT 26 (60%) 57 (44%) CT 11 (26%) 57 (44%) For rs11543848 AA 8 (19%) 26 (20%) 0.073 GG 2 (5%) 18 (14%) GA 33 (77%) 85 (66%) Note: Rs29: rs712829, Rs30: rs712830, Rs54: rs2072454 and Rs48: rs11543848. Haplotype Rs29 Rs30 Rs54 Rs48 Frequency Odd Ratio (95% CI) p‐Value 1 T C T A 0.2118 1.00 — 2 G C T A 0.1748 1.00 (0.31–3.24) 1 3 G C T G 0.1552 0.93 (0.34–2.55) 0.9 4 T C T G 0.1228 1.38 (0.32–5.96) 0.66 5 G C C G 0.0953 1.08 (0.31–3.67) 0.91 6 T C C A 0.0794 1.46 (0.33–6.43) 0.62 7 G C C A 0.0681 0.69 (0.15–3.15) 0.63 8 T C C G 0.0629 168,507 (168,498–168,517) &lt;0.001 9 G A T G 0.0156 0.71 (0.08–6.39) 0.76 Note: Rs29: rs712829, Rs30: rs712830, Rs54: rs2072454 and Rs48: rs11543848.

Association between epidermal growth factor (EGF) and EGF receptor gene polymorphisms and end-stage renal disease and acute renal allograft rejection in a Korean population

Purpose Epidermal growth factor (EGF) has been found to be associated with the development and repair mechanisms of several renal diseases. In this study, we hypothesized that single nucleotide polymorphisms (SNPs) in EGF or its receptor genes might have an association with end-stage renal disease (ESRD) or acute renal allograft rejection (AR) in a Korean population. Methods Three-hundred and forty seven recipients of the first renal transplants for ESRD, including 63 AR patients along with 289 healthy adults were included in the study. Five EGF gene SNPs (rs11568835, rs11568943, rs2237051, rs11569017, and rs3756261) and four EGFR gene SNPs (rs1140475, rs2293347, rs1050171, and rs6965469) were analyzed. The genotypes of these SNPs were analyzed using the AxiomTM genome-wide human assay. Statistical analysis was performed using SNPStats and Haploview version 4.2 software. Multiple logistic regression models (codominant, dominant, recessive, and Log-additive) were used to estimate the odds ratio (OR), 95% confidence interval (CI), and P value. Results One SNP (rs11569017) in the EGF gene showed significant association with ESRD but not with AR. Another SNP (rs11568835) in the EGF gene showed significant association with susceptibility to AR but not with ESRD. One SNP (rs1050171) in the EGFR gene showed significant association with susceptibility to AR but not with ESRD. Conclusion Our findings suggest that SNPs in the EGF and EGFR gene may be associated with the risk of ESRD and AR development in the Korean population.

EGFR Gene Polymorphism Predicts Improved Outcome in Patients With EGFR Mutation-positive Non–small cell Lung Cancer Treated With Erlotinib

BackgroundPatients with advanced-stage non–small cell lung cancer with epidermal growth factor receptor (EGFR) mutations are successfully treated with tyrosine kinase inhibitors (TKIs). However, treatment outcome varies significantly. Previously, we found the polymorphism 181946C>T (rs2293347) located in exon 25 of the EGFR gene to be a predictor of improved outcome. However, these data were based on a subgroup analysis. Furthermore, other minor studies have found conflicting data. Thus, the aim of this study was to demonstrate the association of 181946C>T with clinical outcome in an independent cohort of EGFR-mutated patients treated with erlotinib. Patients and MethodsSeventy-five patients were prospectively enrolled. Blood samples were collected, and genotype for 181946C>T was determined by allele-specific polymerase chain reaction. Genotype was correlated with outcome. ResultsIn 73 patients, 181946C>T was successfully measured. Patients harboring the 181946CT genotype had a significantly longer median progression-free survival compared with patients harboring the 181946CC genotype (49.9 months [95% confidence interval (CI), 5.9-93.9 months] versus 11.1 months (95% CI, 7.4-14.9 months); P = .020). Moreover, a significantly longer median overall survival of 65.6 months (95% CI, 11.0-120.3 months) versus 31.2 months (95% CI, 10.9-51.6 months) was found (P = .019). Both results remained significant in a multivariate analysis adjusting for potential confounders. ConclusionWe demonstrate that the 181946C>T polymorphism is a significant predictor of prolonged progression-free survival and overall survival in an independent cohort of EGFR mutation-positive patients treated with erlotinib. The polymorphism could be an important predictor of treatment response in these patients. A large multicenter cohort study involving other concurrent genetic alterations is warranted.

The Impact of EGFR Gene Polymorphisms on the Risk of Alzheimer's Disease in a Chinese Han Population: A Case-Controlled Study.

BackgroundThe aim of this study was to investigate the association between polymorphisms of the epidermal growth factor receptor (EGFR) gene with the risk of Alzheimer’s disease (AD) in a Chinese Han population.Material/MethodsA polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay was used to genotype 139 patients with AD and 152 healthy control individuals. The Hardy-Weinberg equilibrium (HWE) was analyzed using the chi-squared (χ2) test, and genotype and allele frequencies were compared between the two population groups, using the χ2 test. The odds ratios (ORs) and corresponding 95% confidence intervals (CI) were calculated to express the degree of risk of AD resulting from polymorphisms in the EGFR gene. Linkage disequilibrium among EGFR polymorphisms was analyzed using the Haploview bioinformatics software.ResultsThe CC genotype and C allele frequencies of rs730437 were significantly lower in patients with AD compared with the controls (P=0.037), indicating that rs730437 was associated with a reduced risk of AD (CC vs. AA: OR=0.446, 95% CI=0.207–0.960) (C vs. A: OR=0.702, 95% CI=0.502–0.980). The presence of the TT genotype of rs1468727 significantly reduced the risk of AD (P=0.003; OR=0.333, 95% CI=0.160–0.691), and T allele carriers of rs1468727 had a 0.605-fold increased risk of AD. Haplotype A-C-C was significantly correlated with an increased risk of AD (OR=1.922, 95% CI=1.130–3.269).ConclusionsIn a Han Chinese population, EGFR gene polymorphisms, rs730437 and rs1468727 and haplotype A-C-C were shown to be possible protective factors for the development of AD.

The Association between Epidermal Growth Factor Receptor (EGFR) Gene Polymorphisms and Lung Cancer Risk.

Lung cancer is the leading cause of cancer death globally. The epidermal growth factor receptor (EGFR) plays an important role in cell proliferation and signaling. In this study, we examined the association between EGFR gene polymorphisms and lung cancer risk among the Jordanian population. A total of 129 patients with primary lung cancer and 129 matched healthy controls were recruited into this study. EGFR rs712829, rs712830, rs2072454, and rs11543848 single nucleotide polymorphisms (SNPs) were genotyped to test for their association with lung cancer risk. A significant association was observed between the rs712829 SNP and lung cancer risk (p < 0.05) where the GG + GT genotypes were higher in lung cancer patients when compared to controls. In addition, no association was detected between rs712830, rs2072454, and rs11543848 SNPs and lung cancer risk. When patients were stratified according to the lung cancer type, a significant association was detected between both rs712829 and rs2072454 and adenocarcinoma lung cancer (p < 0.05). Haplotype analysis of all four SNPs showed a significant association between the TCCG haplotype and both lung cancer and the adenocarcinoma subtype (p < 0.001). In conclusion, EGFR rs712829, rs2072454 SNPs, and TCCG haplotypes are associated with a risk of lung cancer among Jordanians. Since genetic associations are affected by the genetic background of populations, more studies in other Arab populations are required to confirm the present findings.

Associations between EGFR gene polymorphisms and susceptibility to glioma: a systematic review and meta-analysis from GWAS and case-control studies.

The results of genome-wide association studies (GWAS) and case-control studies performed to investigate the associations between epidermal growth factor receptor (EGFR) gene polymorphisms and glioma risk are controversial. The aim of this systematic review and meta-analysis is to determine whether EGFR gene polymorphisms are associated with glioma risk by searching ‘PubMed’, ‘EMBASE’, ‘Web of Science’, ‘Cochrane Library’ and ‘China WeiPu Library’ to retrieve studies that investigated associations between EGFR gene polymorphisms and glioma risk. Four GWAS containing 35 studies and 7 case-control studies meeting the inclusion criteria were finally recruited, and 11 single-nucleotide polymorphisms (SNPs) were analyzed. The results showed a significant positive association between rs730437/rs845552 and glioma risk in Asians, and a significant negative association between them in Caucasians. In addition, rs11506105 was significantly associated with an increased risk of glioma in both Asians and Caucasians, and rs11979158 decreased the risk of glioma in Caucasians. However, no significant association was observed between rs12718945/rs17172432/rs4947492 and glioma risk in Asians, between rs2252586 and glioma risk in Caucasians, and between rs3752651 and glioma risk in either Asians or Caucasians. In conclusion, different SNPs in EGFR gene might have different impacts on the risk of glioma in various ethnicities, which offers new insights into the treatment with a target-oriented approach.

Correlations between EGFR gene polymorphisms and pleural metastasis of lung adenocarcinoma.

Proliferation, growth, and differentiation of cells are strictly controlled by the signal system of epidermal growth factor receptor (EGFR). If any link of the EGFR signals system is interfered with or damaged, the proliferation, growth, and differentiation of cells would become uncontrolled. EGFR is overexpressed in a variety of malignant tumors, such as non-small-cell lung cancer, colorectal cancer and breast cancer. Results of the study have proved that EGFR overexpression is closely associated with mutations and variants of the EGFR genes, whose mutations and variants are associated with occurrence, metastasis, and prognosis of different types of tumors, including lung cancer. This study is aimed at investigating whether the polymorphisms of CA simple sequence repeat in intron 1 (CA-SSR1), -216G/T, and R497K in the EGFR are able to induce EGFR activation and whether overexpression is associated with pleural metastasis of lung adenocarcinoma. A total of 432 lung adenocarcinoma patients with pleural metastasis (metastasis group) and 424 patients with lung adenocarcinoma but without pleural metastasis (nonmetastasis group) were enrolled in this study. For all patients, the CA-SSR1 genotypes were determined by capillary electrophoresis, polymerase chain reaction amplification, and direct DNA sequencing, and the R497K and -216G/T genotypes were determined by polymerase chain reaction amplification and direct DNA sequencing. EGFR expression was evaluated by immunohistochemical staining in primary tumor tissues with different -216G/T, R497K, and CA-SSR1 genotypes. Our results showed significant differences between pleural metastasis and nonmetastasis groups in the genotype and allele distribution of -216G/T, R497K, and CA-SSR1 polymorphisms of the EGFR gene. The -216T allele, Arg allele, and shorter CA-SSR1 (<17) had significantly increased risks of pleural metastasis compared with the -216G allele, Lys allele, and longer CA-SSR1 (≥17), respectively. The expression of EGFR was higher in patients with genotypes of -216T/T or -216G/T, Arg/Arg or Arg/Lys, and shorter CA-SSR1 (<17) than that in patients with genotypes of -216G/G, Lys/Lys, and longer CA-SSR1 (≥17), respectively. These results indicate that -216G/T, R497K, and CA-SSR1 polymorphisms are associated with the risk of pleural metastasis of lung adenocarcinoma, which may be related to the overexpression of EGFR protein induced by -216G/T, R497K, and CA-SSR1 polymorphisms.

A synonymous EGFR polymorphism predicting responsiveness to anti-EGFR therapy in metastatic colorectal cancer patients.

Genetic factors are known to affect the efficiency of therapy with monoclonal antibodies (mAbs) targeting the epidermal growth factor receptor (EGFR) in patients with metastatic colorectal cancer (mCRC). At present, the only accepted molecular marker predictive of the response to anti-EGFR mAbs is the somatic mutation of KRAS and NRAS as a marker of resistance to anti-EGFR. However, only a fraction of KRAS wild-type patients benefit from that treatment. In this study, we show that the EGFR gene polymorphism rs1050171 defines, independently of RAS mutational status, a sub-population of 11% of patients with a better clinical outcome after anti-EGFR treatment. Median PFS for patients with the GG genotype was 10.17months compared to 5.37 of those with AG + AA genotypes. Taken together, our findings could be used to better define CRC populations responding to anti-EGFR therapy. Further studies in larger independent cohorts are necessary to validate the present observation that a synonymous polymorphism in EGFR gene impacts on clinical responsiveness.

EGFR gene polymorphisms -216G&gt;T and -191C&gt;A are risk markers for gastric cancer in Mexican population

Epidermal growth factor receptor (EGFR) is a transmembrane glycoprotein with tyrosine-kinase activity that plays an important role in multiple cellular functions. EGFR overexpression has been observed in several types of tumors and it is significantly associated with disease stage, survival, prognosis, and progression of cancer. The polymorphisms -216G>T, -191C>A, and (CA)n first intervening sequence (IVS1) have been related to EGFR overexpression and have been studied in several types of cancer, but not in gastric cancer (GC). The aim of this study was to determine the association of these 3 polymorphisms and GC. Genomic DNA from 68 GC patients and 102 healthy blood donors were analyzed. Polymorphisms were identified by DNA-sequencing (-216G>T and -191C>A) and GeneScan (CA)n IVS1. The results showed that the distribution of the -216G>T and -191C>A genotypes differed between groups (P < 0.05). The odds ratio for the -216TT genotype was 4.59 (95% confidence interval = 1.55-13.54, P < 0.05) and 10.71 (95% confidence interval = 2.31-49.59, P < 0.05) for the -191AA genotype, both in a recessive model. The genotype and allele distributions of the (CA)n IVS1 repeat was similar in both groups. In conclusion, the -216TT and -191AA genotypes and GA haplotype of the EGFR gene were found to be associated with an increased risk of gastric cancer in a Mexican population.

Comprehensive analysis of the association of EGFR, CALM3 and SMARCD1 gene polymorphisms with BMD in Caucasian women.

SummaryThree genes, including EGFR (epidermal growth factor receptor), CALM3 (calmodulin 3, calcium-modulated protein 3) and SMARCD1 (SWI/SNF-related matrix-associated actin-dependent regulator of chromatin subfamily d member 1), play different roles in bone and/or fat metabolism in Caucasian women. In this population-based investigation of 870 unrelated postmenopausal Caucasian women, CALM3 polymorphisms were significantly associated with femoral neck bone mineral density (FNK BMD), hip BMD and spine BMD. Age and tobacco status also affected BMD levels and were therefore corrected for in our statistical analysis.Introduction EGFR, CALM3 and SMARCD1 play roles in bone and/or fat metabolism. However, the correlations between the polymorphisms of these three genes and body composition levels, including BMD, remain to be determined.Materials and MethodsA population-based investigation of 870 white women was conducted. Forty-four SNPs (single nucleotide polymorphisms) in EGFR, CALM3 and SMARCD1 were chosen by the software, including those of potential functional importance. The candidate SNPs were genotyped by the KASPar assay for an association analysis with body composition levels. The correlation analysis was assessed by the Pearson's product-moment correlation coefficient and Spearman rank-order correlation tests, and the family-wise error was corrected using the Wald test implemented in PLINK.ResultsThe SNP rs12461917 in the 3′-flanking region of the CALM3 gene was significantly associated with FNK BMD (P = 0.001), hip BMD (P<0.001) and spine BMD (P = 0.001); rs11083838 in the 5′-flanking region of CALM3 gene was associated with spine BMD (P = 0.009). After adjusting for multiple comparisons, rs12461917 remained significant (P-adjusted = 0.033 for FNK BMD, P-adjusted = 0.006 for hip BMD and P-adjusted = 0.018 for spine BMD).ConclusionsOur data show that polymorphisms of the CALM3 gene in Caucasian women may contribute to variations in the BMD of the hip, spine and femoral neck.

Molecular epidemiology of lung cancer and geographic variations with special reference to EGFR mutations.

Lung cancer is a leading cause of cancer-related mortality in many countries. Although recent advances in targeted therapy against driver oncogenes have significantly improved patient outcome, cure of this disease is still exceptional. Although tobacco is a known cause of lung cancer, not all smokers develop lung cancer, and conversely many patients, especially Asian female patients with lung cancer, are lifetime never-smokers. Therefore, efforts to understand the basis for different susceptibilities to lung cancer among individuals with different genetic, biologic, ethnic, and social backgrounds are important to help develop effective preventive measures. Lung cancer in never-smokers has many different characteristics to lung cancer in smokers, such as adenocarcinoma predominance and high frequency of epidermal growth factor receptor (EGFR) mutation yet low number of genetic changes. Epidemiologic studies suggest that East Asians are more susceptible to smoking-unrelated lung cancer but less susceptible to smoking-related lung cancer compared with Caucasians. Mutations in the EGFR gene are more common in Asian females and never-smokers. Our case-control study suggests that EGFR mutation occurs independent of smoking, and that the apparent low frequency of EGFR mutations in smokers may be the result of dilution by smoking-related lung cancer. The frequencies of three EGFR gene polymorphisms associated with increased protein expression are significantly different between East Asians and Caucasians, favoring lower protein expression in East Asians. Although these may be associated with preferred expression of the EGFR mutant allele, it is difficult to explain the frequent EGFR mutation in Asian patients. Genome wide association studies (GWAS) revealed several loci related to lung cancer susceptibility. In the future, GWAS may identify loci that are specifically related to EGFR-targeted carcinogenesis, leading to identification of carcinogens that induce EGFR mutations and effective prevention measures.

Epidermal Growth Factor Receptor Gene Polymorphisms and Gastric Cancer in Iran

Epidermal growth factor receptor (EGFR) is a transmembrane receptor which contributes to many processes involved in cell survival, proliferation and inhibits apoptosis, that may lead to cancer development. Gastric cancer is one of the most common diseases of digestive system that has low 5-year-survival. The aim of this research was to determine the significance of EGFR tyrosine kinase domain gene polymorphisms in gastric cancer in Iran. In the present study, 83 patients with gastric cancer and 40 normal subjects were investigated for EGFR gene polymorphisms in exons 18-21 by PCR-SSCP. Then, DNA sequencing was conducted for different mobility shift bands. Finally the data were statistically analyzed using the chi-2 test and the SPSSver.16 program. Exon 18 of EGFR gene showed three different bands in SSCP pattern and DNA sequencing displayed one mutation. SSCP pattern of Exons 19 and 21 did not show different migration bands. Exon 20 of EGFR gene revealed multiple migrate bands in SSCP pattern. DNA sequencing displayed 2 mutations in this exon: one mutation was caused amino acid change and another mutation was silent. It may be that EGFR tyrosine kinase gene polymorphisms differ between populations and screening could be useful in gastric cancer patients who might benefit from tyrosine kinase inhibitor therapy.