EGFR and KRAS mutations in Turkish non-small cell lung cancer patients: a pilot study

Detection of EGFR gene polymorphisms in non-small cell lung cancer Egyptian patients: a case-control study

BACKGROUND

Non-Small Cell Lung Cancer displays several genetic mutations including epidermal growth factor receptor. This study's objective was to determine if the EGFR exon19 rs121913438 and exon21 rs121434568 variations play a role in NSCLC susceptibility.

METHODS

Case-control research was done at the Mansoura university oncology center including 124 NSCLC patients, and 124 healthy volunteers. blood was used to obtain genomic DNA. ARMS-PCR was used to genotype single-nucleotide polymorphisms.

RESULTS

Molecular study for EGFR exon 19 del. showed NSCLC cases were significantly associated with a higher proportion of heterozygous WD, WD + DD dominant genotypes, and mutant D allele, (p < 0.05 for each), with a risk to develop NSCLC. also, NSCLC cases were significantly associated with a higher proportion of heterozygous TG, TG + GG dominant genotype, G mutant allele, (p < 0.05 for each), with a risk to develop LC (OR > 1 for each). regarding the two EGFR mutations, TTF1 staining was significantly associated with WD + DD genotypes for EGFR exon 19 del But not EGFR exon 21. No substantial differences were found among all studied cases with CK7 or napsin A Tumor cytochemistry.

CONCLUSIONS

The WD heterozygous genotype and D allele in exon 19 del. mutation as well as the TG heterozygous and G allele in exon 21 substitution mutation in EGFR gene are strongly associated with the development of advanced-NSCLC in the Egyptians.

The role of psychiatry in quality of life in young patients with non-small cell lung cancer

Background

Lung cancer is often seen in geriatric patients, with an age of onset of approximately 60 years. Non-small cell lung cancer (NSCLC) remains the leading cause of cancer-related mortality in the United States and around the world. Young patients are rarely diagnosed with lung cancer, with less than 3.5% of patients presenting with this tumor at an age less than 45. In this paper, we examine NSCLC in young patients, between 18 and 35 years of age, which most commonly occurs in non-smokers and is characterized by a higher proportion of adenocarcinoma histology and advanced disease at presentation. These patients often present with metastasis involving one organ and they test positive for driver gene mutations including, but not limited to, epidermal growth factor receptor (EGFR), tyrosine kinase inhibitor (TKI) sensitive mutation and anaplastic lymphoma kinase (ALK). We addressed depression and anxiety and their effect on quality of life (QOL) and attempted to examine how improvement in QOL in these young patients could affect their course of illness and prognosis.

Methods

We conducted a literature review using PubMed, Cochrane, and Google search. We concentrated our search on two elements, reviewing approximately 50 articles focusing on the driver mutations EGFR and ALK as well as genetic mapping of lung adenocarcinoma in patients aged 18–35 years old. We also conducted a review of approximately 30 articles focusing on quality of life in the context of anxiety and depression within this patient population.

Results

We have described a case of a 28-year-old male with new-onset metastatic lung adenocarcinoma that we had treated in our hospital. He was found to have mutations in EGFR and ALK rearrangement. We aimed to address his depression, anxiety, and poor QOL in the context of his diagnosis. Due to his presenting symptoms leading to the diagnosis of adjustment disorder, he was treated with pharmacotherapy as well as conventional therapy to improve his QOL. Due to the time required to identify mutations, our patient passed away before a more targeted treatment could be offered.

Conclusion

It is important to fully explore the nature of the cancer, including mutation types. Our case demonstrates that the detection of the driver gene mutation EGFR and/or ALK rearrangement could affect treatment and prognosis in this patient population. There are many studies available that highlight targeted therapies for these mutations as well as chemotherapy and radiation. Psychiatry has a significant role in improving quality of life in these patients, which could enhance their response to treatment and survival. Involving psychiatry early in the course results in lower rates of depression, anxiety and premature death.

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Detection of the driver gene mutation EGFR and or ALK rearrangement could affect treatment within the young adult population.

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Early psychiatric intervention can improve quality of life.

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Early psychiatric intervention can lower rates of depression, anxiety, and suicidal ideation.

Synonymous Variants: Necessary Nuance in our Understanding of Cancer Drivers and Treatment Outcomes

Once called "silent mutations" and assumed to have no effect on protein structure and function, synonymous variants are now recognized to be drivers for some cancers. There have been significant advances in our understanding of the numerous mechanisms by which synonymous single nucleotide variants (sSNVs) can affect protein structure and function by affecting pre-mRNA splicing, mRNA expression, stability, folding, miRNA binding, translation kinetics, and co-translational folding. This review highlights the need for considering sSNVs in cancer biology to gain a better understanding of the genetic determinants of human cancers and to improve their diagnosis and treatment. We surveyed the literature for reports of sSNVs in cancer and found numerous studies on the consequences of sSNVs on gene function with supporting in vitro evidence. We also found reports of sSNVs that have statistically significant associations with specific cancer types but for which in vitro studies are lacking to support the reported associations. Additionally, we found reports of germline and somatic sSNVs that were observed in numerous clinical studies and for which in silico analysis predicts possible effects on gene function. We provide a review of these investigations and discuss necessary future studies to elucidate the mechanisms by which sSNVs disrupt protein function and are play a role in tumorigeneses, cancer progression, and treatment efficacy. As splicing dysregulation is one of the most well recognized mechanisms by which sSNVs impact protein function, we also include our own in silico analysis for predicting which sSNVs may disrupt pre-mRNA splicing.

The interaction effects of FEN1 rs174538 polymorphism and polycyclic aromatic hydrocarbon exposure on damage in exon 19 and 21 of EGFR gene in coke oven workers

Polycyclic aromatic hydrocarbon (PAH) exposure and genetic susceptibility were conductive to genotoxic effects including gene damage, which can increase mutational probability. We aimed to explore the dose-effect associations of PAH exposure with damage of exons of epidermal growth factor receptor (EGFR) and breast cancer susceptibility gene 1 (BRCA1), as well as their associations whether modified by Flap endonuclease 1 (FEN1) genotype. Two hundred eighty-eight coke oven male workers were recruited, and we detected the concentration of 1-hydroxypyrene (1-OH-pyr) as PAH exposure biomarker in urine and examined base modification in exons of EGFR and BRCA1 respectively, and genotyped FEN1 rs174538 polymorphism in plasma. We found that the damage indexes of exon 19 and 21 of EGFR (EGFR-19 and EGFR-21) were both significantly associated with increased urinary 1-OH-pyr (both P_trend < 0.001). The levels of urinary 1-OH-pyr were both significantly associated with increased EGFR-19 and EGFR-21 in both smokers and nonsmokers (both P < 0.001). Additionally, we observed that the urinary 1-OH-pyr concentrations were linearly associated with both EGFR-19 and EGFR-21 only in rs174538 GA+AA genotype carriers (both P < 0.001). Moreover, FEN1rs rs174538 showed modifying effects on the associations of urinary 1-OH-pyr with EGFR-19 and EGFR-21 (both P_interaction < 0.05). Our findings revealed the linear dose-effect association between exon damage of EGFR and PAH exposure and highlight differences in genetic contributions to exon damage and have the potential to identify at-risk subpopulations who are susceptible to adverse health effects induced by PAH exposure.

Testing for EGFR Mutations and ALK Rearrangements in Advanced Non-Small-Cell Lung Cancer: Considerations for Countries in Emerging Markets

The treatment of patients with advanced non-small-cell lung cancer (NSCLC) in recent years has been increasingly guided by biomarker testing. Testing has centered on driver genetic alterations involving the epidermal growth factor receptor (EGFR) and anaplastic lymphoma kinase (ALK) rearrangements. The presence of these mutations is predictive of response to targeted therapies such as EGFR tyrosine kinase inhibitors (TKIs) and ALK TKIs. However, there are substantial challenges for the implementation of biomarker testing, particularly in emerging countries. Understanding the barriers to testing in NSCLC will be key to improving molecular testing rates worldwide and patient outcomes as a result. In this article, we review EGFR mutations and ALK rearrangements as predictive biomarkers for NSCLC, discuss a selection of appropriate tests and review the literature with respect to the global uptake of EGFR and ALK testing. To help improve testing rates and unify procedures, we review our experiences with biomarker testing in China, South Korea, Russia, Turkey, Brazil, Argentina and Mexico, and propose a set of recommendations that pathologists from emerging countries can apply to assist with the diagnosis of NSCLC.

Extended-spectrum of KRAS and NRAS mutations in lung cancer tissue specimens obtained with bronchoscopy

Background

Mutations in the RAS genes, HRAS, KRAS, and NRAS, are the most common modifications in many types of human tumors and are found in approximately 30% of all human cancers. These mutations are usually found in codons 12, 13, or 61.

Methods

The aim of this study is to evaluate mutations in codons 59, 117, and 146 of KRAS and NRAS genes in addition to codons 12,13, and 61 of KRAS gene in lung cancer tissue specimens obtained with bronchoscopy. KRAS and NRAS mutation analyses with pyrosequencing were performed on DNA isolated from formalin-fixed paraffin-embedded (FFPE) tissue samples of 64 patients histopathologically diagnosed as lung cancer after bronchoscopic biopsy.

Results

In all, 20 patients (31.2%) had mutations in KRAS gene (8/27 squamous cell carcinoma, 8/11 adenocarcinoma, 3/16 small cell carcinoma, and 1/1 pleomorphic carcinoma). The most common mutation in codon 12 was in c.35G>T (G12V). When the mutation rate of adenocarcinoma (72.7%) and squamous cell carcinoma (22.9%) patients was compared with each other, a statistically significant difference was observed (P = 0.008). There were no mutations in codons 59, 117, or 146 of KRAS and NRAS genes in patients with lung cancer.

Conclusion

In this study, we firstly examined mutations in codons 59, 117, and 146 of KRAS and NRAS genes in addition to codons 12, 13, and 61 of KRAS gene in Turkish lung cancer patients both in non-small cell lung cancer and small cell lung cancer. Although no mutation was detected in codons 59, 117, and 146 of KRAS and NRAS genes, the frequency of KRAS gene mutation was higher than the rate of mutation in both Asian and Western countries, and multicenter studies including more cases should be performed to further explore our results.

EGFR mutation status in a series of Turkish non-small cell lung cancer patients

Epidermal growth factor receptor (EGFR) mutations are potential markers driving carcinogenesis, and may alter the response to EGFR tyrosine kinase inhibitors in patients with non-small cell lung cancer (NSCLC). The frequency of EGFR mutations in patients with NSCLC differs according to sex, smoking habits and regional-based ethnicity differences. The aim of the present study was to determine the frequency of EGFR mutations in Turkish patients with NSCLC to highlight the importance of regional differences, and their associations with patient characteristics. Genomic DNA was extracted from formalin-fixed and paraffin-embedded tumor tissue sections of 409 NSCLC patients. The most common EGFR mutations in exons 18, 19, 20 and 21 were detected using BioFilmChip-based microarray assay. The overall EGFR mutation frequency was 16.6%, and the highest mutation frequencies were observed in exon 19 (6.4%) and exon 21 (7.3%). There was a higher frequency of EGFR mutations in females compared with males and in never-smokers compared with smokers (both P≤0.05). These results were similar to other European population-based studies, but not consistent Middle-Eastern based studies. The present study may contribute to understanding the gradient frequency of EGFR mutation across different ethnicities, and in designing genome wide-based collaborations that may reveal novel decision making and susceptibility mutations in EGFR in patients with NSCLC.

Evaluation of epidermal growth factor receptor mutations and thyroid transcription factor-1 status in Turkish non-small cell lung carcinoma patients: A study of 600 cases from a single center

Background

This study aims to investigate the frequency, distribution, and morphological/immunohistochemical features of epidermal growth factor receptor mutations and to examine the possible relationship between the material type and technical success of mutation analysis in Turkish population with non-small cell lung cancer.

Methods

Between September 2012 and December 2015, a total of 499 consecutive, treatment-naïve patients (437 males, 163 females; mean age 61 years; range, 30 to 84 years) with primary or metastatic non-small cell lung cancer who underwent epidermal growth factor receptor mutation testing using Sanger sequencing method were retrospectively analyzed. Archival records and hematoxylin-eosine and immunohistochemically stained sections were re-examined. The thyroid transcription factor-1 and napsin A immunohistochemical stains were performed on tissue array blocks.

Results

Seventy-five mutations were detected in 70 patients (14%). The success rate of testing and intact deoxyribonucleic acid fragment length were significantly higher in the cytological material, compared to tissue specimens (p<0.001). The mutation rate in adenocarcinomas was 33.9% for women and 9.4% for men. The most common mutation was L746-E750del in exon 19 (29.3%), followed by the L858R mutation in exon 21 (28%). The mutation rate was the highest in micropapillary (40%) and lowest in solid (5.4%) adenocarcinomas. All epidermal growth factor receptor mutations, except for one, were positive for the thyroid transcription factor-1. The single nucleotide polymorphism Q787Q in exon 20 was observed in 79.6% of patients.

Conclusion

The frequency and distribution of epidermal growth factor receptor mutations in the Turkish patients with non-small cell lung cancer are similar to the European populations. These results also demonstrate that cytological materials are highly reliable for epidermal growth factor receptor mutation testing, and the probability of detection of wild-type epidermal growth factor receptor is low in cases of thyroid transcription factor-1 negativity.

EGFR mutation frequency in Middle East and African non-small cell lung cancer patients: a systematic review and meta-analysis

BACKGROUND

Our goal was to investigate the prevalence of the epidermal growth factor receptor (EGFR) mutation in Middle East and African countries and to compare its prevalence with that shown in other populations.

METHODS

We used PubMed and the Cochrane Library databases to conduct a literature search using the terms "[EGFR] AND [mutation] AND [Non Small Cell Lung Cancer] AND [Middle East OR Africa]." We assessed studies published in English and French from 2004 until 2016.

RESULTS

Ten relevant studies were included in this systematic review. Overall, 1215 patients with non-small cell lung cancer (NSCLC) were included in this analysis. The overall ratio of male to female patients was 2.15. Of total patients included, 41.1% had never smoked and 85.8% had been diagnosed with adenocarcinoma. In 8 of the 10 studies, polymerase chain reaction (PCR) analyses were conducted to identify EGFR mutations. In total, 257 patients had an EGFR mutation, corresponding to a prevalence of 21.2%. The most frequent abnormality detected in all of the studies was in exon 19. In addition, all studies concluded the presence of a correlation between EGFR mutation status and female sex, non-smoking status, and adenocarcinoma subtype.

CONCLUSIONS

The EGFR mutation frequency in Middle East and African patients is higher than that shown in white populations but still lower than the frequency reported in Asian populations.

Association between PD-L1 expression and driver gene status in non-small-cell lung cancer: a meta-analysis

OBJECTIVE

To assess the association between PD-L1 expression and driver gene mutations in patients with non-small-cell lung cancer (NSCLC).

METHOD

We performed a meta-analysis of 26 studies (7541 patients) which were published from 2015 to 2017. Pooled odds ratios (ORs) with 95% confidence intervals (CI) were calculated to describe the correlation. Subgroup analysis was performed based on population characteristics, types of PD-L1 antibodies and quality of individual studies.

RESULTS

A lower frequency of PD-L1 positivity was observed in NSCLCs harboring EGFR mutation (OR: 0.64, 95% CI, 0.45-0.91, p = 0.014). A negative correlation was also found at 1% (OR: 0.35, 95% CI, 0.22-0.55, p = 0.000) and 50% (OR: 0.33, 95% CI, 0.14-0.81, p = 0.015) cutoff for PD-L1 positive, elderly age group (OR: 0.56, 95% CI, 0.35-0.89, p = 0.013), female dominant group (OR: 0.55, 95% CI, 0.29-0.94, p = 0.030) and smoker dominant group (OR: 0.52, 95% CI, 0.29-0.96, p = 0.035). No significant differences in PD-L1 expression were observed among patients with different ALK, BRAF, HER2, PIK3CA status and MET expression level. Higher level of PD-L1 was found in tumors with KRAS mutation (OR: 1.45, 95% CI, 1.18-1.80, p = 0.001). PD-L1 expression level was not significantly different between triple (EGFR/ALK/KRAS) wild type NSCLCs and those with EGFR/ALK/KRAS mutation.

CONCLUSIONS

PD-L1 expression in EGFR mutated NSCLCs were lower than those in EGFR wild type NSCLCs, while tumors with KRAS mutation showed higher levels of PD-L1.

EGFR with TKI-sensitive mutations in exon 19 is highly expressed and frequently detected in Chinese patients with lung squamous carcinoma

Recently, tyrosine kinase inhibitors (TKIs) have been recommended as a first-line treatment for advanced non-small cell lung cancer (NSCLC), significantly improving the treatment outcomes of lung adenocarcinoma patients with the EGFR mutation. However, the application of TKIs for lung squamous cell carcinoma (SCC), the second largest pathological subtype of NSCLC, remains controversial because available data for the EGFR mutation profile and frequency in SCC patients are limited. In this study, 89 bronchoscopic-biopsy specimens from Chinese SCC male patients were assayed for EGFR exon 19 mutation, using improved polymerase chain reaction-denature gel gradient electrophoresis. EGFR exon 19 mutations were detected in 77 of 89 (86.5%) patients, and included six kinds of point mutations (11.6%) and two deletions (Del_747-751 [64.9%] and Del_746-751 [23.3%]). We found that the proportion of mutated EGFR varied from 0.98% to 100% in positive specimens and increased with the development of the disease. The difference of proportion between Stage IV patients and Stage II patients or Stage III patients was significant (P<0.001). These results provided valuable clues to explain the reason why patients harboring the same mutation responded distinctly to TKI treatment. Del_747-751 and Del_746-751 were the dominant mutations in the assayed SCC patients (76.4%), and both belong to the EGFR-TKI-sensitive mutation. Recently research demonstrated that Del_746-751 patients have better response to EGFR-TKI than Del_L747-751 patients. However, our study indicated that majority of SCC patients (55.5%) carried Del_ L747-751. We suggest that the unique clinic features of SCC should be further studied to reveal the mechanism of poorer treatment outcome of EGFR-TKI therapy, and that a better treatment plan and more specific, potent targeted drugs for lung SCC need to be developed.

Clinicopathological features of Chinese lung cancer patients with epidermal growth factor receptor mutation

BACKGROUND

Epidermal growth factor receptor (EGFR) gene was the major causative gene of lung cancer and also the specific treatment target. It is necessary to analyze the genotype and phenotype characters of patients.

METHODS

We investigated 1,034 lung cancer patients in this study. The collected clinicopathological parameters included gender, age at diagnosis, smoking status, pathological TNM stage, tumor morphology and location, visceral pleural invasion as well as histological type.

RESULTS

Almost 50% participants had EGFR mutations. L858R in exon 21 was the most common type. Concomitant mutation, 19 del and L858R, were detected in 20 patients. Compared to patients with exon 19 del or L858R mutations solely, they were inclined to have small size adenocarcinomas which occurred in bilateral and invaded the visceral pleura. The tyrosine kinases inhibitors (TKIs)-resistant mutation, insertions in exon 20, was detected in 11 patients.

CONCLUSIONS

The summarized clinicopathological features will help clinicians to implement the feasible treatment plan.

Increased EGFR mRNA Expression Levels in Non-Small Cell Lung Cancer

Objective

In this study, we investigated the frequency of Epidermal growth factor receptor (EGFR) gene mutations, the level of EGFR mRNA and protein expressions in Turkish population for indicating substantial differences in the frequency of EGFR mutations, EGFR amplification and EGFR protein expression between populations and the effect of these parameters in response to EGFR tyrosine kinase inhibitors.

Materials and Methods

The study included 34 patients with non-small cell lung cancers. The RNA and DNA were extracted from the normal and tumor side of the lung tissue removed by surgery. To investigate the most common mutations in the EGFR gene, exon 19 was sequenced and mutation specific PCR was performed for detecting the L858R mutation in exon 21. EGFR mRNA expression was measured by relative quantitative reverse transcription PCR. The EGFR protein levels were detected with immunohistochemistry methods from the sections of the patients' paraffin blocks.

Results

No EGFR mutation in exon 19 or L858R mutation in exon 21 were detected in the patients. Overexpression of EGFR gene mRNA was identified in 16 of 34 (%47) patients and overexpression of EGFR protein was detected in 15 of 34 (%44) patients. Statistical analysis was not significant for the correlation between sex, age, smoking, histopathology, pathological stage and overexpression of EGFR mRNA and protein.

Conclusion

It was found that in Turkish population, EGFR mutation in exon 19 and L858R mutation were very rare, EGFR protein expression was similar and EGFR mRNA expression significantly increased compared to the literature. Markedly increased EGFR mRNA expression ratios in the absence of activating mutations showed that identifying the EGFR mRNA expression level for prediction of response to EGFR tyrosine kinase inhibitors might be significant in the Turkish population.

Epidermal Growth Factor Receptor Activating Mutations in Squamous Histology of Lung Cancer Patients of Southern Bulgaria

There is only limited data on the prevalence of epidermal growth factor receptor (EGFR) activating mutations in squamous cell carcinomas and adenosquamous carcinomas of the lung in patients of the Southern Bulgarian region and the efficacy of EGFR tyrosine kinase inhibitors. AIM: Previous reports for Bulgarian population showed high incidence of EGFR mutations in the squamous cell carcinomas, so we set the goal to investigate their frequency in Southern Bulgaria, after precise immunohistochemical verification of lung cancers. MATERIALS AND METHODS: Two hundred and thirty-six lung carcinomas were included in this prospective study. All biopsies were initially analysed with p63, TTF1, Napsin A, CK7, CK34βE12, synaptophysin, CK20 and CDX2. Two hundred and twenty-five non-small cell lung carcinomas were studied with real-time PCR technology to assess the status of the EGFR gene. RESULTS: We detected 132 adenocarcinomas (58.7%), 89 squamous cell carcinomas (39.2%), 4 adenosquamous carcinomas (1.8%), 9 large cell neuroendocrine carcinomas (3.8%) and 2 metastatic colorectal adenocarcinomas (0.8%). Activating mutations in the EGF receptor had 3 out of 89 squamous cell carcinomas (3.37%). We have established mutations in L858R, deletion in exon 19 and rare mutation in S7681. One out of four adenosquamous carcinomas had a point mutation in the L858R (25%). CONCLUSIONS: The frequency of EGFR mutations we found in lung squamous cell carcinomas in a Southern Bulgarian region is lower than that in European countries. Ethnic diversity in the region does not play role of an independent predictive factor in terms of mutation frequency.