Excision Repair Cross-complementation Group 1 Gene Research Articles

Multi-index comprehensive evaluation of the efficacy and response mechanism of immunotherapy in non-small cell lung cancer.

This research conducted multi-index comprehensive evaluations of the immunotherapeutic efficacy and response in non-small cell lung cancer (NSCLC). Forty-five patients with epidermal growth factor receptor (EGFR)/anaplastic lymphoma kinase (ALK) wild-type advanced NSCLC who received immunotherapy were included. Immunohistochemistry was adopted to detect the expression levels of programmed death ligand 1 (PD-L1) with X-ray cross-complementing protein 1 (XRCC1) and excision repair cross-complementing group 1 (ERCC1) proteins in tumor tissues. Flow cytometry was utilized to measure the levels of T-cell subsets in peripheral blood before and after treatment. PCR-RELP method was employed to evaluate XRCC1 and ERCC1 gene polymorphisms in peripheral blood. According to the treatment effect, patients evaluated as complete response (CR), partial response (PR), and stable disease (SD) were categorized into the immune response group, and patients evaluated as progressive disease (PD) were categorized into the immune unresponsive group. The correlation between PD-L1 protein expression, XRCC1 and ERCC1 protein expression, gene polymorphisms, T-cell subpopulation levels, and treatment efficacy was analyzed. The therapeutic efficacy of patients with positive PD-L1 expression was better than that of patients with negative PD-L1 expression (P < 0.05). After treatment, peripheral blood CD3+ and CD4+ cell levels and Thl/Th2 cell levels were higher and CD8+ T cells were lower in the immune response group than in the immune unresponsive group (P < 0.05). Among the patients in the immune response group, peripheral blood CD3+ and CD4+ cell levels were higher and CD8+ T cells were lower in patients with positive PD-L1 expression than in patients with negative PD-L1 expression (P < 0.05). In the XRCC1 gene, the proportion of patients in the immune response group carrying the Arg/Trp + Trp/Trp genotype was higher than that of patients in the immune unresponsive group (P < 0.05). In the ERCC1 gene, the proportion of patients in the immune response group carrying the C/T + T/T genotype was higher than that of patients in the immune unresponsive group (P < 0.05). The positive expression rates of XRCC1 and ERCC1 in patients in the immune unresponsive group were higher than those in the immune response group (P < 0.05). PD-L1 protein expression, XRCC1 and ERCC1 protein expression, and gene polymorphisms are associated with immunotherapy outcome in EGFR/ALK wild-type advanced NSCLC patients, and may be biological indicators for predicting immunotherapy outcome in EGFR/ALK wild-type advanced NSCLC patients.

The Relationship between Single Nucleotide Polymorphism of ERCC1 Gene and the Response to Platinum Based Chemotherapy in Egyptian Non-Small Cell Lung Cancer Patients

Abstract Background Lung cancer (LC) is the second most common cancer diagnosed in both males and females. There are two subtypes of LC. Non-small cell lung cancer (NSCLC) is the major one. Treatment options for NSCLC depends mainly on the stage at diagnosis. The majority of the patients are diagnosed at advanced stages at time of presentation. Therefore, chemotherapy and radiotherapy play the dominant role in treatment of advanced NSCLC. The most commonly used chemotherapy is platinum-based chemotherapy as cisplatin and carboplatin and third generation drugs as vinorelbine and gemcitabine. The efficacy of platinum-based chemotherapy is limited by chemoresistance. The excision repair cross complementation group 1(ERCC1) gene is a member of nucleotide excision repair pathway that plays a critical role in the DNA repair by removing DNA covalent helix-distorting adducts. Aim of the Work In this study investigated the relationship between single nucleotide polymorphism of ERCC1 rs11615 and the response to platinum-based chemotherapy in Egyptian NSCLC patients in order to prevent the non-necessary exposure to the toxic effect of chemotherapy. Patients and Methods This is a cross-sectional study conducted on 50 NSCLC patients who were recruited from the Oncology Clinic in Ain Shams University Hospitals; twenty of them were responders to platinumbased chemotherapy and the other 30 were non-responders according to RECIST criteria. All subjects underwent full medical history focusing on tobacco smoking and family history of cancers, thorough clinical examination, histological diagnosis of NSCLC and TNM classification, radiological studies: computed tomography of chest and abdomen and laboratory investigations in the form of: complete blood picture (CBC), liver function tests and kidney function tests. Detection of the ERCC1 (T/C) polymorphism by realtime PCR was done for both the responders' and the non-responders' groups. Results There was no significant statistical difference observed between the responders’ and nonresponders’ groups regarding the genotype frequencies nor the allelic frequency (p &amp;gt; 0.05). Conclusion The present study did not confirm the presence of significant association between the genotypic frequencies nor the allelic frequencies of the ERCC1 rs 11615 among the responders' and the non-responders' groups. Further studies with higher sample size are needed to clarify the association.

Association of ERCC1 and XPF polymorphisms with pediatric glioma susceptibility.

Association of ERCC1 and XPF polymorphisms with pediatric glioma susceptibility.

DNA repair in cardiomyocytes is critical for maintaining cardiac function in mice.

Heart failure has reached epidemic proportions in a progressively ageing population. The molecular mechanisms underlying heart failure remain elusive, but evidence indicates that DNA damage is enhanced in failing hearts. Here, we tested the hypothesis that endogenous DNA repair in cardiomyocytes is critical for maintaining normal cardiac function, so that perturbed repair of spontaneous DNA damage drives early onset of heart failure. To increase the burden of spontaneous DNA damage, we knocked out the DNA repair endonucleases xeroderma pigmentosum complementation group G (XPG) and excision repair cross-complementation group 1 (ERCC1), either systemically or cardiomyocyte-restricted, and studied the effects on cardiac function and structure. Loss of DNA repair permitted normal heart development but subsequently caused progressive deterioration of cardiac function, resulting in overt congestive heart failure and premature death within 6months. Cardiac biopsies revealed increased oxidative stress associated with increased fibrosis and apoptosis. Moreover, gene set enrichment analysis showed enrichment of pathways associated with impaired DNA repair and apoptosis, and identified TP53 as one of the top active upstream transcription regulators. In support of the observed cardiac phenotype in mutant mice, several genetic variants in the ERCC1 and XPG gene in human GWAS data were found to be associated with cardiac remodelling and dysfunction. In conclusion, unrepaired spontaneous DNA damage in differentiated cardiomyocytes drives early onset of cardiac failure. These observations implicate DNA damage as a potential novel therapeutic target and highlight systemic and cardiomyocyte-restricted DNA repair-deficient mouse mutants as bona fide models of heart failure.

Genetic Polymorphisms in ERCC1 Gene and Their Association with Response to Radiotherapy in Moroccan Patients with Nasopharyngeal Carcinoma.

Nasopharyngeal carcinoma (NPC) is a severe malignant disease. Despite its low frequency, NPC is very common in North African population. Radiotherapy is the standard therapeutic treatment of NPC. However, radioresistance hampers the success of treatment. At the molecular scale, radioresistance is due to genetic variations involved in DNA repair pathways in NPC patients. Several studies reported that single nucleotide polymorphisms (SNPs) in excision repair cross complementing group 1 (ERCC1) could be associated with radioresistance. In this optic, the present study aimed to evaluate the association between DNA repair gene polymorphisms ERCC1 C8092A and ERCC1 C118T and radiotherapy response of patients with NPC. A total of 95 patients with confirmed NPC were recruited at the Mohammed VI Center for Cancer Treatment, Casablanca - Morocco between 2016 and 2018. Two single nucleotide polymorphisms in ERCC1 gene were genotyped. Multiple analysis software was used to assess the correlation between these SNPs and radio-therapeutic response. Sequencing of ERCC1 C8092A polymorphism revealed that CC and CA genotypes were found in 51.6% and 45.3% of cases, respectively, whereas the homozygote AA genotype was reported in only 3.1% of cases. For ERCC1 C118T polymorphism, the heterozygote CT genotype was identified in 49.5% of cases. Homozygotes genotypes CC and TT were detected in 17.9% and 32.6% respectively of NPC cases. Of note, no significant association was found between the ERCC1 C8092A polymorphism and response to radiation therapy (p=0.81). Similarly, there was no significant association between the response to radiotherapy and allelic distribution (p=0.56). Likewise, no correlation was observed neither with genotypes (p=0.07) nor with alleles (p=0.09) of ERCC1 C118T polymorphism and response to radiation therapy. Our results clearly showed that ERCC1 C8092A and ERCC1 C118T polymorphisms were not associated with response to radiotherapy in Moroccan NPC patients. Large studies are warranted to confirm the role of these SNPs in therapeutic response of NPC patients.

Association between ERCC1 Gene Polymorphism (rs11615) and Colorectal Cancer Susceptibility: A Meta-Analysis of Medical Image Fusion and Safety Applications.

Colorectal cancer (CRC) is a malignant tumor of the colorectal mucosa epithelial tissue transformed. The fusion of data for medical imaging has become a central issue in such biomedical applications as image-guided surgery and radiotherapy. Currently, CRC has been one of the most threatening tumors affecting people's health worldwide. The excision repair cross-complementation group 1 (ERCC1) is a key enzyme for nucleotide excision repair (NER). Emerging epidemiological studies have indicated that the presence of colorectal cancer (CRC) may be relevant to the ERCC1 rs11615 genetic polymorphism. However, the results of ERCC1 rs11615 on CRC in these studies are controversial. We searched PubMed, Web of Science, Embase, CNKI, and CBM databases for the effects of ERCC1 rs11615 variant on CRC development. There was no meta-analysis focused on the diagnosis of colorectal cancer with ERCC1 rs11615 variant. We creatively carried out a meta-analysis of nine case-control studies and used Stata (version 12.0) software to integrate the pooled odds ratios (ORs) corresponding to a 95% confidence interval (CI) of overall and subgroup analysis. Our results suggest that a significant correlation was observed between rs11615 and the susceptibility of CRC OR 95% CI = 1.13 (1.04-1.23) under an allele genetic model and OR 95% CI = 1.14 (1.01-1.30) under a dominant genetic model for overall CRC. Significant statistical difference was also noted in Asians rather than Caucasians based on the ethnicity subgroups. These results suggested that there is a certain association between rs11615 and the susceptibility of colorectal cancer in the Asian populations.

Expression of astrocyte-elevated gene-1 indicates prognostic value of fluoropyrimidine-based adjuvant chemotherapy in resectable stage III colorectal cancer.

It is unclear which prognostic factor such as pathological features and gene mutation are majorly relevant for stage III disease and whether they aid in determining patients who will be benefit from postoperative adjuvant chemotherapy. The expression of astrocyte-elevated gene-1 (AEG-1), thymidylate synthase (TS), excision repair cross-complementation group 1 (ERCC1), epidermal growth factor receptor (EGFR), and vascular endothelial growth factor (VEGF) was examined to investigate their role in adjuvant chemotherapy for patients with resectable stage III colorectal cancer (CRC). A significant positive correlation was observed between AEG-1, TS, ERCC1, EGFR, and VEGF gene expression levels in CRC cell lines, and low AEG-1 and TS expression were highly sensitive to 5-fluorouracil treatment. Our results showed that AEG-1 expression was high in T4 and caused CRC recurrence or metastasis. Patients with T4, high AEG-1, TS and VEGF expression had a significantly short disease-free survival and overall survival. In multivariate Cox regression analysis, high AEG-1 expression could be an independent prognostic factor indicating poor survival in patients with resectable stage III CRC treated with adjuvant chemotherapy. In conclusion, AEG-1 expression and tumor grade are potential prognostic factors for recurrence and survival in patients with stage III CRC receiving adjuvant fluoropyrimidine-based chemotherapy.

Single-arm, open label prospective trial to assess prediction of the role of ERCC1/XPF complex in the response of advanced NSCLC patients to platinum-based chemotherapy

BackgroundPlatinum-based therapy, combined or not with immune checkpoint inhibitors, represents a front-line choice for patients with non-small-cell lung cancer (NSCLC). Despite the improved outcomes in the last years for this malignancy, only a sub-group of patients have long-term benefit. Excision repair cross-complementation group 1 (ERCC1) has been considered a potential biomarker to predict the outcome of platinum-based chemotherapy in NSCLC. However, the ERCC1 gene is transcribed in four splice variants where the isoform 202 was described as the only one active and able to complex Xeroderma pigmentosum group F-complementing protein (XPF). Here, we prospectively investigated if the active form of ERCC1, as assessed by the ERCC1/XPF complex (ERCC1/XPF), could predict the sensitivity to platinum compounds.Patients and methodsProspectively enrolled, patients with advanced NSCLC treated with a first-line regimen containing platinum were centrally evaluated for ERCC1/XPF by a proximity ligation assay. Overall survival (OS), progression-free survival (PFS) and objective response rate (ORR) were analyzed.ResultsThe absence of the ERCC1/XPF in the tumor suggested a trend of worst outcomes in terms of both OS [hazard ratio (HR) 1.41, 95% confidence interval (CI) 0.67-2.94, P = 0.373] and PFS (HR 1.61, 95% CI 0.88-3.03, P = 0.123). ORR was marginally influenced in ERCC1/XPF-negative and -positive groups [odds ratio (stable disease + progressive disease versus complete response + partial response) 0.87, 95% CI 0.25-3.07, P = 0.832].ConclusionThe lack of ERCC1/XPF complex in NSCLC tumor cells might delineate a group of patients with poor outcomes when treated with platinum compounds. ERCC1/XPF absence might well identify patients for whom a different therapeutic approach could be necessary.

Modulation of DNA damage by XPF, XPG and ERCC1 gene polymorphisms in pesticide-exposed agricultural workers of Punjab, North-West India

Inter-individual variations in DNA repair capacity (DRC) for repairing pesticide-induced DNA oxidation damage may influence adverse health outcomes. We aimed to evaluate whether polymorphisms in genes involved in nucleotide excision repair (NER) pathway could modulate DNA damage in pesticide-exposed agricultural workers. Xeroderma pigmentosum group F (XPF) (Arg415Gln, G1244A, rs1800067), xeroderma pigmentosum group G (XPG) (Asp1104His, G3507C, rs17655), excision repair cross complementation group 1 (ERCC1) (3′UTR, C8092A, rs3212986) and ERCC1 (Asn118Asn, C19007T, rs11615) polymorphisms were analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique in 225 pesticide-exposed agricultural workers and 225 controls from Punjab, North-West India. The assessment of DNA damage was carried out by alkaline comet assay. Kruskal-Wallis test was used to evaluate the association of gene polymorphisms in NER pathway with DNA damage. Pesticide-exposed agricultural workers carrying variant XPF Gln/Gln (AA) genotype showed higher comet tail length (p < 0.01) than wild type Arg/Arg (GG) genotype. The comet tail length (p < 0.01) was found to be significantly increased in exposed agricultural workers carrying XPG His/His (CC) genotype than wild-type Asp/Asp (GG) genotype. In relation to the individuals carrying wild type ERCC1 3′UTR CC genotype, exposed individuals with variant ERCC1 3′UTR CA genotype showed elevation in the comet tail length (p = 0.029). However, we found no association of ERCC1 Asn118Asn (C19007T) genotype with DNA damage. These results indicate that XPF, XPG and ERCC1 genes of NER pathway may modulate the efficacy of the DNA repair system against pesticide exposure in our population.

Expression and Genetic Polymorphisms of ERCC1 in Chinese Han Patients with Oral Squamous Cell Carcinoma.

The aim of this study was to investigate the expression of the excision repair cross-complementation group 1 (ERCC1) in oral squamous cell carcinoma (OSCC) and the possible association of ERCC1 polymorphisms with susceptibility and response to chemotherapy of OSCC in a Chinese Han population. The expression of ERCC1 was determined by real-time PCR in eight patients. Four single-nucleotide polymorphisms (SNPs) rs11615, rs3212948, rs3212961, and rs735482 of ERCC1 were genotyped in 113 OSCC patients and 184 healthy controls using a PCR restriction matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS) assay. We found that a higher gene expression of ERCC1 was observed in tumor tissue as compared to pericarcinomatous tissue in OSCC patients. All genotypic and allelic frequencies of the tested ERCC1 polymorphisms were in Hardy-Weinberg equilibrium. The genotypic and allelic frequencies of rs11615, rs3212948, rs3212961, and rs735482 of ERCC1 were not different between OSCC patients and controls. No correlation was observed between ERCC1 polymorphisms and the response to chemotherapy. Our results show that ERCC1 is increased in the tumor tissue of OSCC patients. The investigated ERCC1 gene polymorphisms (rs11615, rs3212948, rs3212961, and rs735482) are not associated with the susceptibility and response to chemotherapy of OSCC in our investigated Chinese Han population.

Abstract 353: Expression of astrocyte-elevated gene-1 is associated with prognostic value of adjuvant chemotherapy in resectable stage III colorectal cancer

Abstract Background: Administration of postoperative adjuvant chemotherapy has reduced the risk of tumor recurrence and improved survival for patients with resected colorectal cancer (CRC). Regarding the prognostic factors, including pathologic features and gene mutation have major relevance for stage III disease, it is not well known whether they might help select patients who would fare favorably when received adjuvant chemotherapy. OBJECTIVE: Expression of astrocyte-elevated gene-1 (AEG-1), thymidylate synthase (TS), excision repair cross-complementation group 1 (ERCC1), epidermal growth factor receptor (EGFR), vascular endothelial growth factor (VEGF) were needed to investigate the role involved in adjuvant combination therapy for patients with resectable stage III colon cancer. Methods: AEG-1, TS, ERCC1, EGFR and VEGF were investigated by CRC cell lines and intra-tumor immunohistochemistry stain. Furthermore, this study collected 29 patients with stage III colorectal cancer who underwent surgical resection from 2011 to 2016 and received postoperative adjuvant chemotherapy. The culmination of clinical data registration included surgical procedures, tumor size, number of lymph node metastases, and types of chemotherapy drugs. Result: A significant positive correlation between AEG-1, TS, ERCC1, EGFR, and VEGF gene expression levels were revealed in CRC cell lines. Cell lines with lower AEG-1 and TS expression had higher sensitivity to 5-FU treatment. In clinical studies, we found that higher AEG-1 expression was noted in T4 and also caused CRC recurrence or metastasis. Patients with T4 and stage IIIC CRC had a significantly shorter DFS (T4 v.s. T1-3, DFS, months, median: 4.1 ± 1.2 v.s. non-reach [NR], p &amp;lt; 0.001; IIIC v.s. IIIA or IIIB, DFS, months, median: 10.6 ± 5.3 v.s. NR, p = 0.037; respectively). Patients with higher AEG-1 and TS expression had a shorter DFS (AEG-1, high v.s. low, months, median: 12.8 ± 2.4 v.s. NR, p = 0.003; TS, high v.s. low, months, median: 13.8 ± 2.3 v.s. NR, p = 0.012; respectively). In multivariate Cox Regression analysis, advanced tumor invasion (T4) and high AEG-1 expression could be an independent prognostic factor to cause poor survival in resectable stage III CRC patients treated with adjuvant chemotherapy. Conclusion: Expressions of AEG-1 and tumor grade as a candidate prognostic factor of recurrence in stage III colorectal cancer patients receiving adjuvant fluoropyrimidine-based chemotherapy. A prospective cohort study should be guaranteed to validate these factors to be predictive markers of adjuvant chemotherapy benefit for stage III CRC. Citation Format: Chung-Yu Chen, Peng-Sheng Lai, Ying-Yin Chen, Long-Wei Lin. Expression of astrocyte-elevated gene-1 is associated with prognostic value of adjuvant chemotherapy in resectable stage III colorectal cancer [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 353.

Abstract 4932: Excision repair cross-complementing group-1 (ERCC1) induction and polymorphism are markers of inferior outcome in patients with colorectal cancer treated with oxaliplatin

Abstract Background: Oxaliplatin confers tumoricidal effect by forming platinum-DNA adducts and is an integral part of the treatment paradigm for patients with colorectal cancer (CRC). The nucleotide excision repair pathway (NERP) plays a crucial role in tissue resistance to the drug. We have previously demonstrated that ERCC1 (part of NERP) is an inducible gene in CRC cell lines on exposure to oxaliplatin, and high levels confer drug resistance. We aimed to translate these findings by using Peripheral Blood Mononuclear Cells (PBMC) as a surrogate and assess ERCC1 as a biomarker of sensitivity to oxaliplatin therapy. Additionally, we assessed prevalence of single nucleotide polymorphisms (SNP) and its relation to patient outcomes. Methods: In consenting patients with CRC who received oxaliplatin, blood was sampled at 0, 2, 48 hours, and 14 days during any cycle of chemotherapy, and/or DNA from formalin fixed paraffin embedded (FFPE) tissue was isolated. ERCC1 gene expression was quantified by qPCR (quantitative real time polymerase chain reaction) and WB (western blotting). SNPs were analyzed through Sanger sequencing of DNA from blood or tissue. Clinical benefit from oxaliplatin was determined using the parameters of relapse free survival (RFS) for limited stage and progression free survival (PFS) for mCRC. Results: 54 patients had serial blood sampled; 25 (46.3%) had mCRC and 1 was excluded due to mortality prior to therapy. 13 (52%) had an increase in ERCC1 expression from baseline, while 11 (48%) showed no change or decrease. Median PFS was 190 and 237 days respectively (log-rank test HR 2.35, CI 1.005-5.479; p = 0.0182). In the 29 patients with limited stage disease, 19 (65.5%) had an induction of ERCC. In these patients change in expression did not correlate with RFS. We did not find any significant correlation of PFS with baseline expression of ERCC1 in either group. SNP in rs11615 (AAT&amp;gt;AAC, 97 samples) was assessed. 80/97 had stage 4 disease, with AAC in 69 (86.3%) patients. Median PFS was lower in patients with AAC than AAT (203 vs 684.5 days; log-rank test HR 2.4, CI 1.45-3.97, p=0.0045). On analysis of racial distribution, blacks had the highest prevalence of AAC (100%), followed by Hispanics (81.8%), persons of mixed race (76.9%) and whites (68.8%) (Fisher exact test p=0.0004). Conclusions: We confirm our hypothesis that the ERCC1 gene is induced in vivo in a sub-population of patients on treatment with oxaliplatin. This induction can serve as a potential marker of drug-resistance in mCRC as evidenced by the significant difference in PFS. Additionally, presence of SNP is an independent marker of drug resistance, which has a significant pattern of distribution among various races. Analysis of a second SNP (rs3212986), also implicated in drug resistance, is underway. Citation Format: Devika Rao, Atrayee Basu Mallick, Titto Augustine, Cecilia Daroqui, Jeeshan Jiffry, Amartej Merla, Imran Chaudhary, Raviraja Seetharaman, Arjun Sood, Srikanth Gajavelli, Santiago Aparo, Lakshmi Rajdev, Andreas Kaubisch, Jennifer Chuy, Radhashree Maitra, Sanjay Goel. Excision repair cross-complementing group-1 (ERCC1) induction and polymorphism are markers of inferior outcome in patients with colorectal cancer treated with oxaliplatin [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4932.

The role of ERCC1 and AFP gene polymorphism in hepatocellular carcinoma.

The aim of this study was to evaluate the effects of polymorphisms in excision repair cross-complementation group 1 (ERCC1) and alpha-fetoprotein (AFP) genes and their haplotypes on the susceptibility to hepatocellular carcinoma (HCC), and to decipher the association between single-nucleotide polymorphisms (SNPs) and clinicopathologic characteristics of HCC.Peripheral blood DNA was extracted from 206 subjects. SNaPshot technique was used for genotyping 5 SNP sites of the ERCC1 rs735482, rs1046282, rs3212948, and AFP rs737241, rs4024 genotypes. Chi-squared test and logistic regression model were used to analyze the relationship of different genotypes or haplotype and the susceptibility and clinicopathologic characteristics of HCC.The frequency of GG.GA and AA genotypes at the AFP rs737241 site in the case and control groups showed statistically significant differences (P < .05). The risk of HCC in subjects carrying mutated allele A (GA+AA) was increased by 0.543-times (P < .05) compared to that in the subjects with the GG genotype. Significant differences were observed in the linkage disequilibrium between 2 of the five SNPs (P < .05); the frequency of ERCC1 C-C and AFP A-A haplotypes was significantly lower in the case group than in the control group (P < .05). The results of clinicopathologic analysis showed that A allele at the rs737241 locus could increase the expression level of AFP (P = .007), the rs1046282 mutation C allele could increase the AFP expression level (P = .011), rs4024 locus mutation A allele could reduce the risk of vascular invasion (P = .013), rs3212948 locus mutation T allele could reduce the differentiation of liver cancer (P = .022), rs1046282 locus C allele could reduce the DNA load of hepatitis B virus (P = .035), and rs735482 A allele could increase the tumor size in HCC (P = .037).The SNPs in rs737241 for AFP gene may correlate with the occurrence of HCC. The SNPs in ERCC1 and AFP genes may affect the prognosis of HCC, offering reliable information for early prediction of tumor progression and diagnosis of HCC.

Excision repair cross-complementing group-1 (ERCC1) gene induction in peripheral blood mononuclear cells as a marker of outcome in patients with colorectal cancer treated with oxaliplatin.

542 Background: Oxaliplatin is a third generation platinum agent that confers tumoricidal effect by forming platinum-DNA adducts and is an integral part of the standard of care regimens for patients with colorectal cancer (CRC). Tissue resistance to oxaliplatin appears to be multifactorial, with the nucleotide excision repair (NER) pathway playing a major role. We have previously demonstrated that Excision Repair Cross-Complementing group-1 (ERCC1), can be induced in colorectal cell lines on exposure to Oxaliplatin and high levels confer resistance to apoptosis. We aim to further this knowledge by analyzing gene expression in vivo, using PBMC as a surrogate, to assess ERCC1 as a biomarker of sensitivity to Oxaliplatin therapy. Methods: Patients with CRC who received oxaliplatin were consented to blood (PBMC) sampling at 0, 2, 48 hours, and 14 days during any cycle of chemotherapy. ERCC1 gene expression was quantified by qPCR (quantitative real time polymerase chain reaction) and WB (western blotting). Clinical benefit from oxaliplatin was determined using the parameters of relapse free survival (RFS) for limited stage and progression free survival (PFS) for mCRC. Results: Fifty-four patients were enrolled on study, 25 (46.3%) had mCRC. Twenty-four patients were included in final analysis based on clinical data. Thirteen (52%) had an increase in ERCC expression from baseline, while 11 (48%) showed no change or decrease. Median PFS was 190 and 237 days respectively (log-rank test HR 2.35, CI 1.005-5.479; p = 0.0182). In the 29 patients with limited stage disease, 19 (65.5%) had an induction of ERCC. However, in these patients change in expression did not correlate with RFS. We did not find any significant correlation of PFS with baseline expression of ERCC1 in either group. Conclusions: We confirm our hypothesis that the ERCC1 gene is induced in vivo in a sub-population of patients on treatment with Oxaliplatin. This induction can serve as a potential marker of resistance to oxaliplatin based chemotherapy in mCRC as evidenced by the significant difference in PFS. Further analyses of the influence of ERCC1 polymorphisms on outcomes is underway.

PO534 Cost-Effectiveness Analysis of Therapeutic Hypothermia In Critical Patient After Cardiac Arrest: Estimate of Lifetime Horizon Follow-Up

Customized chemotherapy has several advantages: patients are more likely to be treated with the most effective agents and can be spared the toxicity of ineffective drugs. Based on the literature, excision repair cross complementation group 1 (ERCC1) and ribonucleotide reductase M1 (RRM1) genes represent predictive biomarkers of response to platinum compound and gemcitabine, in NSCLC.We had planned a phase II trial (Simon design) to evaluate combination chemotherapy according to single nucleotide polymorphisms (SNPs) of ERCC1 (118T/C and 8092C/A) and RRM1 (−37C/A and −524T/C) in naïve patients affected by advanced NSCLC. ERCC1 and RRM1 SNPs assessment was performed in peripheral blood lymphocytes (PBLs). Combination chemotherapy was selected based on ERCC1 and RRM1 SNPs: we assume that patients with one or two C alleles at position 118 and with one or two A alleles at position 8092 in ERCC1 gene would correspond to Cisplatin non-responder and than with two A alleles at −37 and two C alleles at −524 in RRM1 gene to gemcitabine non-responder. Four schedules were provided: cisplatin + gemcitabine, cisplatin + docetaxel, gemcitabine + docetaxel; docetaxel + vinorelbine. Primary endpoint was overall response (ORR) in the intention-to-treat population.42 patients were enrolled from January 2010 to November 2011; 40 patients received at least 1 cycle of chemotherapy; median age was 66 years (range: 47–72); 36(90%) had stage IV, 4(10%) IIIB; 23(58%) had adenocarcinoma, 14(35%) squamous carcinoma. Twenty-five (62%) patients received treatment A, 3(8%) treatment B, 11(28%) treatment C, 1(23%) treatment D. ORR was 55%, analysis in squamous patients subgroups showed 71.4% ORR. The median follow-up was 19.7 months, PFS was 23 weeks (95% CI = 15–26) and OS was 40.4 weeks (95% CI = 32–55). Treatment was well tolerated.We observed an increase of ORR in NSCLC patients when they were treated with chemotherapy according to ERCC1 and RRM1 SNPs status.

Excision repair cross complementation group 1 (ERCC-1) gene polymorphisms and response to nivolumab in advanced non-small cell lung cancer (NSCLC).

3032 Background: Anti PD1 antibodies showed significant clinical activity in different cancer types. Recently, it was observed that cancers with higher somatic mutation burden, as tumors with genome instability due to DNA repair defects, develop more elevated anti PD1 induced neoantigen specific T cell reactivity which results into increased susceptibility to PD1 blockade. We hypothesize that NSCLC pts with single nucleotide polymorphisms (SNPs) of the ERCC-1 gene, a key enzyme of DNA nucleotide excision repair pathway, may be more responsive to PD-1 blockade due to their genetic instability. Methods: We evaluated the rs11615 and rs3212986 ERCC1 SNPs by pyrosequencing analysis on tumor DNA of stage IIIb-IV previously treated NSCLC patients receiving Nivolumab (Nivo) 3 mg/kg q2w. To be eligible for this study, pts had to have a complete record of clinical and radiological parameters. Objective tumour response was assessed according to RECIST 1.1 criteria. Results: Between Jul 2015 and Jan 2016, 45 NSCLC pts received Nivo. Pts characteristics were as follows: M/F = 37/8; median age (range) = 64 (38-80); ECOG PS, 0/1/2 = 33/9/3; Stage IIIb/IV = 8/37; sqNSCLC/non sq NSCLC = 11/34; current-former smokers/non-smokers = 40/5; EGFR status, mutant/wildtype/unknown = 4/35/6; median cycles (range) = 12 (1-28). Only two pts presented the rs11615 SNP. 16 pts were positive for the rs3212986 SNP. ORR for all pts was 26.6% (95% CI, 10 to 47). The ORR was significantly higher in NSCLC pts positive for the rs3212986 SNP than for wild-type NSCLC patients (62.5% vs. 6.9%. p = 0.0001). For all pts median PFS was 4.3 mos (95% CI, 1.2 to 7.4)and median OS not-reached. Among pts positive for the rs3212986 SNP, median PFS and OS were 8.2 mos and not-reached respectively. In contrast wild-type patients presented a median PFS of 3.1 mos (HR = 0.21 95% CI, 0.07 to 0.57; p = 0.02) and a median OS of 6.5 mos (HR = 0,403 95% CI = 0,131-1,237 p = 0.11). Multivariate analyses confirmed the effect of rs3212986 SNP after adjustment for age, PS, sex and disease stage for PFS. Conclusions: This study suggests that genetic instability due to tumor ERCC1 SNPs in advanced NSCLC pts may be of value to predict clinical benefit from Nivo.

Relationship between excision repair cross-complementation group 1 methylation and sensitivity to cisplatin-based concurrent chemoradiotherapy in cervical squamous cell carcinoma

Objective To investigate the correlation of the excision repair cross-complementation group 1(ERCC1) gene methylation status with sensitivity to cisplatin-based concurrent chemoradiotherapy and clinical pathological characteristics in patients with cervical squamous cell carcinoma (CSCC). Methods Methylation specific polymerase chain reaction was used to determine the ERCC1 gene methylation status in cervical tissue from 20 healthy people and 60 patients with CSCC. All patients with CSCC were treated with cisplatin-based concurrent chemoradiotherapy. The treatment outcomes were evaluated using the Response Evaluation Criteria in Solid Tumors. Based on the treatment outcomes, patients with a complete response were assigned to chemoradiotherapy-sensitive group, and patients with a partial response, stable disease, or progressive disease were assigned to chemoradiotherapy-resistant group. Comparison of the ERCC1 gene methylation status between the two groups was made by χ2 test, and multivariate logistic regression analysis was used to analyze the relationship of the ERCC1 gene methylation status with various clinical pathological characteristics and sensitivity to chemoradiotherapy. Results The ERCC1 gene methylation rate was significantly higher in cervical tissue with CSCC than in normal cervical tissue (60% vs. 0%, P=0.000). The multivariate analysis showed that ERCC1 gene methylation was an independent influencing factor for sensitivity to cisplatin-based concurrent chemoradiotherapy in CSCC (P=0.022); ERCC1 gene methylation was significantly correlated with histological grade of CSCC (P=0.030); there was no significant relationship of ERCC1 gene methylation with clinical pathological characteristics including age, tumor size, lymph node metastasis, FIGO stage, and pretreatment hemoglobin and platelet count (P=0.729, 0.707, 0.340, 0.747, 0.073, 1.000). Conclusions The ERCC1 gene promoter methylation status may be involved in the development and progression of CSCC. It may also influence the sensitivity of patients with CSCC to cisplatin-based concurrent chemoradiotherapy by playing a role in cell differentiation. Key words: Excision repair cross-complementation group 1; Radiosensitivity; Cervical neoplasms/radiotherapy; Cervical neoplasms/chemotherapy

Heterogeneity of excision repair cross-complementation group 1 gene expression in non-small-cell lung cancer patients.

Excision repair cross-complementation group 1 (ERCC1) gene expression analysis is currently used widely in the molecular diagnosis of cancer. According to numerous studies, ERCC1 gene expression correlates with overall survival and effectiveness of chemotherapy with platinum agents. However, the degree of this correlation differs among various studies, with certain authors reporting a complete lack of such a correlation. These contradictions may be attributed to a number of factors, including the heterogeneity of the tumor tissue. In this study, we attempted to assess the degree of genetic heterogeneity exhibited by tissue samples obtained from non-small-cell lung cancer (NSCLC) through the expression of the ERCC1 gene. This study included 25 samples of tumor tissue from patients with a morphologically confirmed NSCLC diagnosis. A total of three randomized sections of each specimen were used. The ERCC1 gene expression was assessed by quantitative polymerase chain reaction (qPCR) in the TaqMan format. When planning the experiment and analysis of qPCR data, the MIQE guidelines were taken into consideration. We established that the coefficient of variation of the relative level of ERCC1 gene expression in the majority of the samples exceeded 33% (P<0.05), indicating the significant heterogeneity of the sample. We also demonstrated that the degree of heterogeneity of the tumor tissue is largely dependent on disease stage.

ERCC1 gene polymorphism in gastric cancer.

As a crucial part of the DNA damage repair process,the expression of excision repair cross-complementing group 1 （ERCC1 ）is closely related to the genesis and development of gastric cancer.Studies find that ERCC1 gene polymorphism can alter the expression of the gene itself,which affects the sensitivity and efficacy of platinum-based chemotherapy.Therefore,the detection of ERCC1 polymorphism may guide the indi-vidualized chemotherapy of the patients with gastric cancer. Key words: Stomach neoplasms; Polymorphism, single nucleotide; ERCC1

192P - Prognostic Biomarkers in Malignant Pleural Mesothelioma

ABSTRACT Aim: The standard of care for malignant pleural mesothelioma (MPM) includes combination of platinum compounds and pemetrexed. Despite this, the median survival of MPM patients is still bad (12 months). Excision Repair Cross Complementing Group 1 (ERCC1) acts removing DNA adducts formed by platinum compounds, whereas Pemetrexed inhibits Thymidylate Synthase (TS), a folic enzyme also involved in ex novo synthesis of DNA. This study aims to analyse retrospectively, in a large series of MPM specimens, the ERCC1 and TS gene and protein expression to investigate their prognostic and predictive role. Methods: Pleural biopsies were collected from140 consecutive MPM patients (98 males and 42 females, mean age 68 years, range 27-90). Histologic subtypes were: epithelioid (#103, 73%), sarcomatoid (#19, 14%) and biphasic (#18, 13%). At the end of the study 113 patients were died (average disease specific survival (DSS) 13 months; range 1-60); mRNA was extracted from formalin fixed paraffin embedded blocks and reverse transcribed in cDNA to perform gene expression assay by qRT-PCR. Immunohistochemistry was performed by anti-ERCC1 and anti-TS mAbs and the results were scored from 0 to 3 depending on the percentage of positive tumour cells and staining intensity. The results were statistically correlated with the clinical features and with the DSS of the patients respectively by Fisher's exact test and Logrank test. Results: Of 140 patients 102 received platinum and pemetrexed (in single or in combination), the remaining were untreated due to bad performance status, advanced age or refusing therapy. Statistically significant correlation was found between the lack of protein expression of ERCC1 and DSS in the whole cohort (P = .03). Low levels of TS mRNA were significantly correlated with the DSS in the whole cohort (P = .01) and in the untreated subgroup (including patients not receiving pemetrexed) (P = .04), whereas did not in the subgroup of pemetrexed treated patients Conclusions: ERCC1 protein expression, scored by IHC, and TS gene expression, evaluated by mRNA analysis, seem both important prognostic markers; we suggest their evaluation in routine biopsies from patients with MPM. Disclosure: All authors have declared no conflicts of interest.