Excision Repair Cross-complementation Group Research Articles

P2.03b-054 Biomarker Predictors in NSCLC: Topic: Biomarkers

Among the major challenges in the chemotherapeutic regimens is lacking of effective biomarkers for drug response and sensitivity. Our current study reviewed two promising biomarkers, ERCC1 (excision repair cross-complementing group 1) and RRM1 (ribonucleotide reductase group 1) to identify their potentiality to predict responder to Cisplatin and Gemcitabine among NSCLC (Non-Small Cell Lung Cancer) patients. Prospectively, this study was conducted in National Cancer Institute (NCI) Cairo, Egypt. We measured the mRNA expression level of ERCC1 and RRM1 in tumor cells (using Real-time quantitative PCR) isolated from Stage IIIB/IV NSCLC patients planned to receive Cisplatin and Gemcitabine. Patients were divided into two groups, either both low ERCC1 and RRM1 (group 1) or both are high (group 2). Our objectives were the correlation between both groups and clinical response (CR), Progression free survival (PFS) and Overall Survival (OS). 55 patients were enrolled and followed from Jan 2011 to Jan 2014, Median age was 57(30-75years), 87% had ECOG-PS1, 86% had stage IV, responder (SD/PR) represented 56%. 30 patients had both low ERCC1 and RRM1 (group 1) while the rest 25 patients had high ERCC1 and RRM1 (group 2). There was no significant differences between different clinical response in both groups (P= 0.239), however multivariate Cox regression analysis revealed responders (p=0.007, HR0.33) and high ERCC1/RRM1 RNA (p=0.032, HR;2.51) to be the only predictors of overall survival. Patients in group 1 had longer median PFS (9.8 ms vs 4.9 ms, P= 0.001) and longer median OS (12.5 ms vs 6.2 ms, P<0.001) than patients in group 2. Low ERCC and RRM1 RNA levels serve as a guidance to predict chemosensitivity to cisplatin and Gemcitabine, with longer survival. Combination of ERCC1 and RRM1 RNA has a prognostic and predictive significance in Stage IIIB/IV NSCLC patients receiving Cisplatin and Gemcitabine. Large cohort studies are warranted.

Association between XRCC1 and ERCC1 single-nucleotide polymorphisms and the efficacy of concurrent radiochemotherapy in patients with esophageal squamous cell carcinoma

The aim of the present study was to investigate the association between single-nucleotide polymorphisms (SNPs) in X-ray repair cross-complementing 1–399 (XRCC1-399) or excision repair cross-complementation group 1–118 (ERCC1-118) and the short-term efficacy of radiochemotherapy, tumor metastasis and relapse, as well as the survival time in patients with esophageal squamous cell carcinoma (ESCC). TaqMan probe-based quantitative polymerase chain reaction (qPCR) was conducted to examine the levels of XRCC1-399 and ERCC1-118 SNPs in the peripheral blood of 50 patients with pathologically confirmed ESCC. In addition, the associations between different genotypes and short-term therapeutic efficacy [the complete remission (CR) rate], tumor metastasis and relapse, as well as the survival time following concurrent radiochemotherapy, were determined. A total of 50 ESCC patients who received concurrent radiochemotherapy were enrolled. It was found that the short-term therapeutic efficacy (CR rate) was higher in the group of patients carrying the homozygous mutation of XRCC1-399 (A/A genotype) than in the group of patients without the XRCC1-399 mutation (G/G genotype). In addition, the CR rate was significantly increased in patients carrying one or two ERCC1-118 C alleles (C/C or C/T genotype) compared with patients lacking the C allele (T/T genotype). The differences were statistically significant (A/A vs. G/G, P=0.014; TT vs. C/T+C/C, P=0.040). During the follow-up period, the group of patients carrying the homozygous mutation of XRCC1-399 (A/A genotype) exhibited a markedly reduced risk of metastasis and relapse compared with the group of patients carrying non-mutated XRCC1-399 (G/G genotype; P=0.031). By contrast, ERCC1-118 SNP was not associated with the risk of metastasis and recurrence (P>0.05). The combined results of univariate and multivariate Cox regression analysis showed that the SNP in ERCC1-118 was closely associated with survival time. The mean survival time was significantly prolonged in patients carrying 1 or 2 C alleles (C/C or C/T genotype) compared with patients lacking the C allele (T/T genotype) [T/T vs. C/C, HR=12.96, 95% confidence interval (CI)=3.08–54.61, P<0.001; TT vs. C/T+C/C, HR=11.71, 95% CI=3.06–44.83, P<0.001]. However, XRCC1-399SNP had no effect on survival time (P>0.05). XRCCl-399 SNP was associated with the short-term therapeutic efficacy (the CR rate) and tumor metastasis/relapse in ESCC patients who received the docetaxel plus cisplatin (TP) regimen-based concurrent radiochemotherapy. By contrast, ERCC1-118 SNP was significantly associated with the short-term therapeutic efficacy (the CR rate) and survival time in ESCC patients who received TP regimen-based concurrent radiochemotherapy.

The 5'UTR variant of ERCC5 fails to influence outcomes in ovarian and lung cancer patients undergoing treatment with platinum-based drugs.

The common polymorphic variant in the 5′ untranslated region of the excision repair cross-complementation group 5 (ERCC5) gene was described to generate an upstream open reading frame that regulates both the basal ERCC5 expression and its ability to be synthesized following DNA damage. This variant was reported to affect response to platinum therapy in a cohort of patients with pediatric ependymoma. The role of this variant was investigated in two cohorts of cancer patients, specifically in non-small-cell lung cancer (NSCLC) patients (N = 137) and in epithelial ovarian carcinoma (EOC) patients (N = 240), treated in first-line with platinum-based compounds. Differently from what reported for pediatric ependymoma, the analysis of the polymorphism in NSCLC patients cohort was not able to detect any difference among patients harboring different genotypes both in progression free survival (HR = 0.93; 95%CI 0.64–1.33; p-value = 0.678) and overall survival (HR = 0.90; 95%CI 0.62–1.33; p-value = 0.625). These data were corroborated in a EOC patients cohort, where similar progression free survival (HR = 0.91; 95% CI 0.67–1.24; p-value = 0.561) and overall survival (HR = 0.98; 95% CI 0.71–1.35; p-value = 0.912) were found for the different genotypes. These data, obtained in appropriately sized populations, indicate that the effect of this ERCC5 polymorphism is likely to be relevant only in specific tumors.

473P Personalized treatment of advanced non-small cell lung cancer based on excision repair cross-complementation group 1 (ERCC-1) expression

473P Personalized treatment of advanced non-small cell lung cancer based on excision repair cross-complementation group 1 (ERCC-1) expression

Clinicopathological and immunohistochemical features of lung invasive mucinous adenocarcinoma based on computed tomography findings.

BackgroundWe performed an analysis to clarify differences in clinicopathological and molecular features of lung invasive mucinous adenocarcinoma (IMA) based on computed tomography (CT) findings and their impact on prognosis.Patients and methodsOn the basis of CT findings, we divided lung IMA into three subtypes: solid, bubbling, and pneumonic. We then investigated differences in clinicopathological characteristics, prognosis, and the expressions of well-identified biomarkers, including cyclooxygenase-2 (Cox-2), excision repair cross-complementation group 1 (ERCC1), ribonucleotide reductase M1 (RRM1), class III beta-tubulin, thymidylate synthase (TS), secreted protein acidic and rich in cysteine (SPARC), programmed cell death-1 ligand-1 (PD-L1), and epidermal growth factor receptor mutation, among the three subtypes.ResultsA total of 29 patients with resected lung IMA were analyzed. Compared with the solid or bubbling type, the pneumonic type had a higher proportion of symptoms, a larger tumor size, a higher pathological stage, and a significantly worse prognosis. The immunohistochemical findings tended to show high expression of RRM1, class III beta-tubulin, and Cox-2 in the tumor and of SPARC in the stroma, but not of ERCC1, TS, and PD-L1 in the tumor. None of the biomarkers with high expression levels in the tumor were prognostic biomarkers, but the expression of SPARC in the stroma was correlated with a poor outcome.ConclusionClinical and pathological features, in conjunction with molecular data, indicate that IMA should be divided into different subgroups. In our results, the pneumonic type was correlated with a significantly worse outcome. Further studies should be performed to confirm our conclusion and to explore its molecular implications.

473P Personalized treatment of advanced non-small cell lung cancer based on excision repair cross-complementation group 1 (ERCC-1) expression

473P Personalized treatment of advanced non-small cell lung cancer based on excision repair cross-complementation group 1 (ERCC-1) expression

The ERCC1-4533/8092, TNF-α 238/308 polymorphisms and the risk of hepatocellular carcinoma in Guangxi Zhuang populations of China: Case-control study.

Objective:To investigate the relationship between excision repair cross-complementing group 1 (ERCC1)-4533/8092, tumor necrosis factor-alpha (TNF-α)-238/308 polymorphisms, and the risk of hepatocellular carcinoma (HCC) in Guangxi Zhuang population of China.Methods:Polymerase chain reaction-restriction fragment length polymorphism method was used to detect the ERCC1-4533/8092 and TNF-α-238/308 polymorphisms in 88 cases with HCC and 82 cases of normal control.Results:There were no differences in the frequency distribution of ERCC1-4533 and TNF-α-238 polymorphisms in the HCC group and the control group (P > 0.05). The genotype frequency distributions of the ERCC1-8092 and TNF-α-308 in the HCC group and the control group were different (P < 0.05). Compared with ERCC1-8092 CC genotype, ERCC1-C8092 CA/AA genotype had higher risk of HCC (CA/AA vs CC; odds ratio 3.51, 95% confidence interval 1.03–12.016). Compared with TNF-α-308 GG genotype, TNF-α-308 GA/AA genotype was significantly associated with an increased risk of HCC (GA/AA vs GG; odds ratio 3.84, 95% confidence interval 1.011–14.57).Conclusion:The genetic polymorphisms of ERCC1-8092 and TNF-α-308 are associated with the risk of HCC in Guangxi Zhuang population of China.

18F-fludrodeoxyglucose maximal standardized uptake value and metabolic tumor burden are associated with major chemotherapy-related tumor markers in NSCLC patients.

ObjectiveMetabolic activity and tumor burden are significant for prognosis and metastasis of non-small cell lung cancer (NSCLC), including maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG). Chemotherapy resistance is a great challenge for treating NSCLC patients and is also closely related with several biomarkers such as epidermal growth factor receptor (EGFR), p53, and excision repair cross-complementing group 1 protein (ERCC1). Our purpose was to determine the correlation between positron emission tomography/computed tomography (PET/CT) parameters and tumor markers-related chemotherapy resistance in NSCLC.MethodsForty-six NSCLC chemotherapy-naïve patients were enrolled. The SUVmax, MTV, and TLG were calculated by PET/CT imaging, and expression of EGFR, p53, and ERCC1 were analyzed by immunohistochemistry on tissues. SUVmax, MTV, and TLG compared for their performance in predicting the expression of EGFR, p53, and ERCC1 were illustrated with statistical analysis.ResultsSUVmax was significantly correlated with p53 expression (P=0.001), and MTV and TLG were significantly associated with ERCC1 (P=0.000; P=0.000). Furthermore, multiple stepwise regression analysis revealed that SUVmax was the primary predictor for p53, MTV and TLG was the primary predictor for ERCC1. SUVmax had a sensitivity of 91% and specificity of 50% for the detection of p53 positive. The sensitivities of MTV and TLG were 83% and 80%, and specificities were 69% and 75% for the detection of ERCC1 positive, respectively. When we suggested p53 or ERCC1 positive, the cutoff value of SUVmax, MTV, and TLG were 7.68, 23.62, and 129.65 cm3, respectively.ConclusionSUVmax, MTV, and TLG were closely associated with p53 and ERCC1’ expressions. Therefore, 18F-fludrodeoxyglucose PET/CT could be a new way of predicting p53 or ERCC1-related chemotherapy effect in NSCLC patients with more convenience.

086 The role of Excision Repair Cross-Complementation Group 8 protein in the modulation of oxidative stress and senescent-associated secretory phenotype in keratinocytes from a patient suffering from Cockayne syndrome

086 The role of Excision Repair Cross-Complementation Group 8 protein in the modulation of oxidative stress and senescent-associated secretory phenotype in keratinocytes from a patient suffering from Cockayne syndrome

Genomic characterization of response to chemoradiation in urothelial bladder cancer.

The authors characterized the genetic landscape of chemoradiation-treated urothelial carcinoma of the bladder (UCB) with the objective of identifying potential correlates of response. Primary tumors with (n = 8) or without (n = 40) matched recurrent tumors from 48 patients who had non-metastatic, high-grade UCB and received treatment primarily with chemoradiation were analyzed using a next-generation sequencing assay enriched for cancer-related and canonical DNA damage response (DDR) genes. Protein expression of meiotic recombination 11 homolog (MRE11), a previously suggested biomarker, was assessed in 44 patients. Recurrent tumors were compared with primary tumors, and the clinical impact of likely deleterious DDR gene alterations was evaluated. The profile of alterations approximated that of prior UCB cohorts. Within 5 pairs of matched primary-recurrent tumors, a median of 92% of somatic mutations were shared. A median 33% of mutations were shared between 3 matched bladder-metastasis pairs. Of 26 patients (54%) who had DDR gene alterations, 12 (25%) harbored likely deleterious alterations. In multivariable analysis, these patients displayed a trend toward reduced bladder recurrence (hazard ratio, 0.32; P = .070) or any recurrence (hazard ratio, 0.37; P = .070). The most common of these alterations, ERCC2 (excision repair cross-complementation group 2) mutations, were associated with significantly lower 2-year metastatic recurrence (0% vs 43%; log-rank P = .044). No impact of MRE11 protein expression on outcome was detected. A similar mutation profile between primary and recurrent tumors suggests that pre-existing, resistant clonal populations represent the primary mechanism of chemoradiation treatment failure. Deleterious DDR genetic alterations, particularly recurrent alterations in ERCC2, may be associated with improved chemoradiation outcomes in patients with UCB. A small sample size necessitates independent validation of these observations. Cancer 2016;122:3715-23. © 2016 American Cancer Society.

Abstract 2890: ERCC5 variant rs2296147 T-allele creates a predicted TP53 binding site and up-regulates transcript abundance in normal bronchial epithelial cells, while rs17655 C-allele is linked to miRNA binding site variant and down regulates

Abstract Background: Excision repair cross-complementation group 5 (ERCC5) gene plays an important role in nucleotide excision repair (NER) and dysregulation of ERCC5 is associated with increased lung cancer risk. This study was conducted to characterize cis-acting genetic variants responsible for inter-individual variation in ERCC5 transcript regulation in normal bronchial epithelial cells (NBEC). Methods: We determined genotypes at putative ERCC5 cis-regulatory single nucleotide polymorphic sites (SNP) rs751402 and rs2296147, and marker SNPs rs1047768 and rs17655. Using a recently developed targeted sequencing method, ERCC5 allele-specific transcript abundance was assessed in NBEC RNA from 55 individuals heterozygous for rs1047768 and 21 subjects heterozygous for rs17655. Syntenic relationships among alleles at rs751402, rs2296147 and rs1047768 were assessed by allele-specific PCR followed by Sanger sequencing. We assessed association of NBEC ERCC5 allele-specific expression at rs1047768 with haplotype and diplotype structure at putative ERCC5 promoter cis-regulatory SNPs rs751402 and rs2296147. Results: Genotype analysis revealed higher inter-individual variation in allelic ratios in cDNA samples relative to matched gDNA samples at both rs1047768 and rs17655 (p&amp;lt;0.0001 and p = 0.0005 respectively). By haplotype analysis, mean expression was higher at the rs1047768 alleles syntenic with rs2296147 T allele compared to rs2296147 C allele (p = 0.0030). Sequence analysis predicts that T allele at SNP rs2296147 creates a TP53 binding site. Mean expression was higher at rs17655 G allele (p&amp;lt;0.0001) which is syntenic with G allele at a linked SNP rs873601 (r2 = 0.74). C allele at SNP rs873601 is predicted to create a miRNA binding site. Conclusions: These data support the conclusion that T allele at SNP rs2296147 creates a TP53 binding site and up-regulates ERCC5 while C allele at SNP rs873601 creates a miRNA binding site and down-regulates ERCC5. Variation in ERCC5 transcript abundance associated with allelic variation at these SNPs is likely associated with variation in NER function in NBEC and lung cancer risk. Citation Format: Xiaolu Zhang, Erin L. Crawford, Thomas M. Blomquist, Sadik A. Khuder, Jiyoun Yeo, Albert M. Levin, James C. Willey. ERCC5 variant rs2296147 T-allele creates a predicted TP53 binding site and up-regulates transcript abundance in normal bronchial epithelial cells, while rs17655 C-allele is linked to miRNA binding site variant and down regulates. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2890.

Comprehensive Biomarkers for Personalized Treatment in Pulmonary Large Cell Neuroendocrine Carcinoma: A Comparative Analysis With Adenocarcinoma

The prognosis for patients with large cell neuroendocrine carcinoma (LCNEC) of the lung is extremely poor, and optimal treatment strategies have not yet been established. To improve prognoses in patients with LCNEC, this study analyzed immunohistochemical expression and gene mutations of several known molecular targets in LCNECs and compared the expression levels of these targets with those in lung adenocarcinomas. Twenty-six patients with primary LCNEC and 40 patients with adenocarcinoma were analyzed. Excision repair cross-complementation group 1 (ERCC1), class III β-tubulin, topoisomerase I, topoisomerase II, epidermal growth factor receptor (EGFR)-L858R, and somatostatin receptor expression were evaluated by immunohistochemistry, and EGFR mutations were evaluated using direct DNA sequencing and the Scorpion-amplified refractory mutation system. In patients with LCNEC and adenocarcinoma, positive rates of topoisomerase I, topoisomerase II, ERCC1, class III β-tubulin, EGFR-L858R, and somatostatin were 100.0% and 100.0%, 65.4% and 15.0% (p<0.0001), 42.3% and 17.5% (p= 0.0462), 46.2% and 62.5%, 0.0% and 20.0% (p= 0.0182), and 50.0% and 5.0% (p < 0.0001), respectively. The frequencies of EGFR mutations were 0.0% and 37.5% in LCNEC and adenocarcinoma (p= 0.0002), respectively. Five-year overall survival rates were 64% in LCNEC and 91% in adenocarcinoma in stage I (p= 0.0132). Multivariate analysis showed that LCNEC histologic type was an independent prognostic factor in stage I. LCNEC showed overexpression of topoisomerase II, somatostatin, and ERCC1. These findings suggested that it was possible to have good response to treatment with etoposide and octreotide and that LCNEC may be resistant to platinum-based therapy compared with adenocarcinoma. EGFR mutations were not observed in LCNEC. These results may indicate a favorable response to adjuvant treatments that are not typically prescribed for non-small cell lung cancer.

Chemoresistance factors in non-small cell lung cancer

Lung cancer takes the leading position in cancer morbidity and mortality structure in the world and Ukraine. Advanced stages are diagnosed in more than 70% of lung cancer patients. Chemotherapy remains the main method of treatment for advanced lung cancer. Currently, the standard of chemotherapy in patients with III–IV stages of non-small cell lung cancer (NSCLC) is a combination of cisplatin/carboplatin with paclitaxel, etoposide, gemcitabine and vinorelbine. Although, the objective response rate after chemotherapy treatment is only about 20–50%. Low rates of chemotherapy efficacy are connected with chemoresistance of tumor to definite chemotherapeutic agents. Tumor chemoresistance is the result of different tumor intracellular mechanisms activity. Basing on current data we tried to analyze prognostic and predictive value of main chemoresistance factors in NSCLC. Conclusions . Nowadays we can certainly affirm that chemoresistance to cisplatin in NSCLC is due to increased expression of ERCC1 (Excision repair cross-complementation group 1 protein), BCRP; and resistance to taxanes is connected with elevated expression of β-tubuline III class; and tumoral chemoresistance to gemcitabine is due to high RRM1 (Ribinucleotide reductase M1) expression. High expression of BRCA1 (Breast Cancer 1) protein in tumors leads to increase of tumor cells resistance to cisplatin, but at the same time it increases the sensitivity to taxanes. Therefore, investigation of tumor chemoresistance plays an important role in algorithms’ creation for optimal chemotherapy schemes selection in patients with different stages of NSCLC in order to achieve the best tumor response to treatment and improve overall and disease-free survival. The information of main NSCLC chemoresistance factors, its prognostic and predictive value are presented in this overview.

High ERCC1 expression is associated with platinum-resistance, but not survival in patients with epithelial ovarian cancer.

The present study aimed to investigate the association between excision repair cross-complementation group 1 (ERCC1) expression and clinical resistance to platinum-based chemotherapy or clinical characteristics, including survival time, in patients with epithelial ovarian cancer (EOC). ERCC1 expression was determined by immunohistochemical staining in 92 tumor specimens from patients with EOC. The effect of ERCC1 expression on progression-free survival time (PFS) or overall survival time (OS), and its association with clinical resistance to platinum-based chemotherapy was investigated by Kaplan-Meier survival analysis, Cox regression analysis and the χ2 test. Of 92 patients with EOC, 89.13% (82/92) had ERCC1-positive tumors. The positive rate was significantly higher in platinum-resistant patients compared with those who were platinum-responding (P<0.05). The PFS and median OS were 12 and 30 months, respectively, in ERCC1 high expression patients, and 17 and 39 months, respectively, in ERCC1 low expression patients. However, there was no statistically significant difference in PFS (P=0.099) or OS (P=0.103) between the high and low expression groups. Furthermore, it was identified that ERCC1 was not an independent factor affecting the prognosis of patients with EOC based on Cox proportional hazards regression analysis. These results demonstrate that high ERCC1 expression is associated with resistance to platinum-based chemotherapy, but not with survival time, and ERCC1 protein expression is not an independent factor or the only factor affecting the prognosis of patients with EOC.

ERCC1 Expression Can Predict Response to Platinum-Based Induction Chemotherapy in Head and Neck Cancer Cases.

To investigate whether excision repair cross complementing-group1 (ERCC1) expression status could serve as a bio-predictor of response to platinum-based induction chemotherapy for head and neck cancers (HNCs) patients with a diagnosis of epithelial HNC were studied retrospectively. Paraffin embedded tumor samples of the patients were analyzed by reverse transcription-polymerase chain reaction (RT-PCR) to determine ERCC1 expression status and its correlation with response to platinum-based induction chemotherapy was investigated. Of 44 included patients, 33 were male (75%) and 11 were female (25%) with a mean age of 53 years. Some 36% of patients whose tumor samples had high ERCC1 expression showed no response to induction chemotherapy. The value for patients with low ERCC1 expression was 9% and the difference was statistically significant (p=0.03). The ERCC1 expression state did not significantly vary between patient groups according to sex, age, primary tumor site, and tumor and node stage. Our study indicates that ERCC1 expression status detected by RT-PCR might serve as a bio-predictor of response to platinum-based induction chemotherapy for epithelial HNCs.

Haplotype and diplotype analyses of variation in ERCC5 transcription cis-regulation in normal bronchial epithelial cells.

Excision repair cross-complementation group 5 (ERCC5) gene plays an important role in nucleotide excision repair, and dysregulation of ERCC5 is associated with increased lung cancer risk. Haplotype and diplotype analyses were conducted in normal bronchial epithelial cells (NBEC) to better understand mechanisms responsible for interindividual variation in transcript abundance regulation of ERCC5 We determined genotypes at putative ERCC5 cis-regulatory SNPs (cis-rSNP) rs751402 and rs2296147, and marker SNPs rs1047768 and rs17655. ERCC5 allele-specific transcript abundance was assessed by a recently developed targeted sequencing method. Syntenic relationships among alleles at rs751402, rs2296147, and rs1047768 were assessed by allele-specific PCR followed by Sanger sequencing. We then assessed association of ERCC5 allele-specific expression at rs1047768 with haplotype and diplotype structure at cis-rSNPs rs751402 and rs2296147. Genotype analysis revealed significantly (P < 0.005) higher interindividual variation in allelic ratios in cDNA samples relative to matched gDNA samples at both rs1047768 and rs17655. By diplotype analysis, mean expression was higher at the rs1047768 alleles syntenic with rs2296147 T allele compared with rs2296147 C allele. Furthermore, mean expression was lower at rs17655 C allele, which is syntenic with G allele at a linked SNP rs873601 (D' = 0.95). These data support the conclusions that in NBEC, T allele at SNP rs2296147 upregulates ERCC5, variation at rs751402 does not alter ERCC5 regulation, and that C allele at SNP rs17655 downregulates ERCC5 Variation in ERCC5 transcript abundance associated with allelic variation at these SNPs could result in variation in NER function in NBEC and lung cancer risk.

Low-level laser irradiation alters mRNA expression from genes involved in DNA repair and genomic stabilization in myoblasts

Low-level lasers are used for the treatment of diseases in soft and bone tissues, but few data are available regarding their effects on genomic stability. In this study, we investigated mRNA expression from genes involved in DNA repair and genomic stabilization in myoblasts exposed to low-level infrared laser. C2C12 myoblast cultures in different fetal bovine serum concentrations were exposed to low-level infrared laser (10, 35 and 70 J cm−2), and collected for the evaluation of DNA repair gene expression. Laser exposure increased gene expression related to base excision repair (8-oxoguanine DNA glycosylase and apurinic/apyrimidinic endonuclease 1), nucleotide excision repair (excision repair cross-complementation group 1 and xeroderma pigmentosum C protein) and genomic stabilization (ATM serine/threonine kinase and tumor protein p53) in normal and low fetal bovine serum concentrations. Results suggest that genomic stability could be part of a biostimulation effect of low-level laser therapy in injured muscles.

Functional Analysis of SNPs in the ERCC5 Promoter in Advanced Colorectal Cancer Patients Treated With Oxaliplatin-Based Chemotherapy.

The promoter is the center for regulation of gene transcription due to containing numerous transcription factor binding sites. The aim of the study was to determine whether genetic variations at excision repair cross complementation group 5 (ERCC5) promoter could affect transcription factor binding and whether such single nucleotide polymorphism (SNP)-dependent binding could affect gene expression, drug response, and clinical outcome.A total of 170 patients who were cytologically or histologically confirmed with advanced colorectal cancer (CRC), at least 1 measurable lesion, and underwent oxaliplatin-based chemotherapy were studied. The polymerase chain reaction–ligation detection reaction (PCR-LDR) was used to analyze SNPs. The reporter gene assay system and electrophoretic mobility shift assays (EMSA) were performed to investigate the effect of SNPs on the ERCC5 promoter activity and DNA-binding activity, respectively. The mRNA and protein expression of ERCC5 in tumor tissues of colorectal cancer patients with different genotypes were detected by real-time PCR and western blot, respectively.Both −763A and −763G allele had nuclear protein-binding ability. +25A allele did not show any nuclear protein-binding ability, whereas +25G allele did. The relative luciferase activity of the −763A/+25G haplotype was significantly higher than other 3 haplotypes (P < 0.05). The expression level of ERCC5 mRNA and protein was significantly higher in tumor tissues with −763AA+25GG genotype combination than that with −763GG+25AA genotype combination (P < 0.05, respectively). Allelic variants (−763AA vs −763AG or –763GG, +25GG versus +25AG or +25AA) were significantly associated with shorter progression-free survival (PFS) and overall survival (OS) (P < 0.05, respectively). At multivariate analysis, patients with risk genotypes (−763AA or +25GG genotype) demonstrated a significantly increasing risk of progression (P = 0.01) or worse OS (P = 0.001).The ERCC5 promoter polymorphisms at −763 and +25 may be important functional variants and predictors of clinical outcome of CRC patients who received oxaliplatin chemotherapy.

MRP1 expression in CTCs confers resistance to irinotecan-based chemotherapy in metastatic colorectal cancer.

Circulating tumor cells are important markers of tumor progression and can reflect tumor behavior in metastatic colorectal cancer (mCRC). Identification of proteins that confer resistance to treatment is an important step to predict response and better selection of treatment for patients. Multidrug resistance-associated protein 1 (MRP1) and Multidrug resistance-associated protein 4 (MRP4) play a role in irinotecan-resistance, and Excision Repair Cross-Complementation group 1 (ERCC1) expression can confer resistance to platinum compounds. Here, we included 34 patients with mCRC and most of them received FOLFIRI or FOLFOX chemotherapy (91.1%). CTCs were isolated by ISET(®) Technology and identified in 30 patients (88.2%), with a median of 2.0 CTCs/mL (0-31.0). We analyzed the immunocytochemical expression of MRP1, MRP4 and ERCC1 only in patients who had previously detectable CTCs, accordingly to treatment received (n = 19, 15 and 13 patients, respectively). Among patients treated with irinotecan-based chemotherapy, 4 out of 19 cases with MRP1 positive CTCs showed a worse progression free survival (PFS) in comparison to those with MRP1 negative CTCs (2.1 months vs. 9.1 months; p = 0.003). None of the other proteins studied in CTCs had significant association with PFS. We analyzed also histological sections of primary tumors and metastases by immunohistochemistry, and found no association with clinicopathological characteristics or with PFS. Our results show MRP1 as a potential biomarker of resistance to treatment with irinotecan when found in CTCs from mCRC patients. This is a small proof-of-principle study and these early findings need to be validated in a larger cohort of patients.

ERCC1 expression affects outcome in metastatic pancreatic carcinoma treated with FOLFIRINOX: A single institution analysis.

IntroductionNo clinically useful predictive factor has been yet identified for treatment of metastatic pancreatic cancer (mPC). It is noteworthy that FOLFIRINOX, despite its high toxicity, is effective only in some patients. We retrospectively analyzed expression of excision repair cross-complementing group-1 (ERCC1) - involved in the repair of platinum induced damage - in patients affected by mPC treated with FOLFIRINOX in order to evaluate its predictive role.ResultsFOLFIRINOX resulted more effective in patients with normal ERCC1 levels than in those with ERCC1 hyper-expression. Median progression free survival (PFS) was 11 vs. 4 months (HR 0.26; 95% CI 0.14-0.50; p<.0001), median overall survival (OS) 16 vs. 8 months (HR 0.23; 95% CI 0.12-0.46; p<.0001) and disease control rate (DCR) 93% vs. 50% (p=0.00006). The advantage was confirmed at univariate and multivariate analysis.Patients and Methods71 patients with histologically proven mPC and treated with FOLFIRINOX as first-line therapy were considered eligible. mRNA ERCC1 expression was determined using RT-PCR analysis.DiscussionERCC1 might be an effective predictor of response to FOLFIRINOX in mPC. Patients overexpressing ERCC1 should be excluded by this often toxic therapy and referred to an alternative treatment.