ERCC1基因在非小细胞肺癌中的作用

化疗是非小细胞肺癌治疗的主要手段之一,而耐药是影响化疗疗效的重要因素。切除修复交叉互补基因1是核苷酸切除修复的关键基因,其基因表达及基因多态性与铂类耐药存在相关性,从而影响非小细胞肺癌对化疗敏感性及疗效。     

Genetic variation in the DNA repair genes is predictive of outcome in lung cancer

To assess whether DNA repair gene variants influence the clinical behaviour of lung cancer we examined the impact of a comprehensive panel of 109 non-synonymous single-nucleotide polymorphisms (nsSNPs) in 50 DNA repair genes on overall survival (OS) in 700 lung cancer patients. Fifteen nsSNPs were associated with OS, significantly greater than that expected (P = 0.04). SNPs associated with prognosis mapped primarily to two repair pathways--nucleotide excision repair (NER): ERCC5 D1104H (P = 0.004); ERCC6 G399D (P = 0.023), ERCC6 Q1413R (P = 0.025), POLE (P = 0.014) and base excision repair: APEX1 D148E (P = 0.028); EXO1 E670G (P = 0.007); POLB P242R (P = 0.018). An increasing number of variant alleles in EXO1 was associated with a poorer prognosis [hazard ratio (HR) = 1.24; P = 0.0009]. A role for variation in NER and BRCA2/FA pathway genes as determinants of OS was provided by an analysis restricted to the 456 patients treated with platinum-based agents. Our data indicate that the pathway-based approach has the potential to generate prognostic markers of clinical outcome.     

Lack of correlation between ERCC1 (C8092A) single nucleotide polymorphism and efficacy/toxicity of platinum based chemotherapy in Chinese patients with advanced non-small cell lung cancer

PurposeWe investigated whether single nucleotide polymorphism of excision repair cross-complementation group 1 C8092A affected the clinical outcomes and toxicity in advanced stage non-small cell lung cancer patients receiving first line platinum based chemotherapy.Material/MethodsA total of 300 chemotherapy treated patients were examined for C8092A genotypes in peripheral blood samples.ResultsOverall response rate was 33.6% and median overall survival was 13.5 months. There was no significant correlation between C8092A single nucleotide polymorphism and overall survival, tumor response or toxicity for platinum-based chemotherapy.ConclusionsExcision repair cross-complementing group 1 (ERCC1) showed controversial results in different studies that have been carried out until now. In our Chinese population there is no correlation between ERCC1 C8092A SNP and efficacy or toxicity. Ethnicity could be a possible explanation for these controversial results.     

Clinicopathological significance of ERCC1 expression in breast cancer

The excision repair cross-complementation 1 (ERCC1) enzyme plays an essential role in the nucleotide excision repair pathway and is associated with resistance to platinum-based chemotherapy in different types of cancer. The aim of the present study was to evaluate the clinicopathological significance of ERCC1 expression in breast cancer patients. We analyzed the immunohistochemical expression of ERCC1 in a tissue microarray from 135 primary breast carcinomas and correlated the immunohistochemical findings with clinicopathological factors and outcome data. ERCC1 expression analysis was available for 109 cases. In this group, 58 (53.2%) were positive for ERCC1. ERCC1-positive expression was correlated with smaller tumor size (P = 0.007) and with positivity for estrogen receptor (P = 0.040), but no correlation was found with other clinicopathological features. Although not statistically significant, triple negative breast cancers were more frequently negative for ERCC1 (61.5% of the cases) compared to the non-triple negative breast cancer cases (41.5%). In conclusion, ERCC1 expression correlated significantly with favorable prognostic factors, such as smaller tumor size and ER-positivity, suggesting a possible role for ERCC1 as a predictive and/or prognostic marker in breast cancer.     

ERCC1 mutations in UV-sensitive Chinese hamster ovary (CHO) cell lines

In mammalian nucleotide excision repair (NER), the ERCC1 protein is known to act as a complex with ERCC4 (XPF) protein, which is necessary for stability of ERCC1, and this complex introduces an incision on the 5′ side of a damaged site in DNA. ERCC1 also binds to XPA protein to make a large protein complex at the site of DNA damage. Since no human disease associated with ERCC1 has been identified, Chinese hamster ovary (CHO) cell lines defective in ERCC1 are a unique source for characterization of ERCC1 deficiency in mammalian cells. We have isolated the full length ERCC1 cDNA from a wild-type CHO cell line and analyzed mutations in two CHO cell lines which fall into complementation group 1 of UV-sensitive rodent cell lines. One cell line, 43-3B, has a missense mutation at the 98th residue (V98E). The in vitro translated mutant protein of 43-3B is unable to bind to XPA protein. Although the mutant protein is able to bind to XPF protein in vitro, the mutant protein is highly unstable in vivo. These defects presumably cause the NER deficiency of this cell line. Another mutant, UV-4, has an insertion mutation in the middle of the coding sequence, resulting in a truncated protein due to a nonsense codon arising from the frameshift. Thus, these two mutant cell lines are deficient in the function of the ERCC1 gene for NER.     

Role of common ERCC1 polymorphisms in cisplatin‐resistant epithelial ovarian cancer patients: A study in Chinese cohort

Epithelial ovarian cancer (EOC) contributes the majority of death cases among various ovarian malignancies. Although a standard method of treatment is the surgical removal of malignant tissue followed by platinum‐based chemotherapy, a group of patients does not respond appropriately to cisplatin. An appropriate response to cisplatin has been linked with the nucleotide excision repair mechanism. The present study aims to investigate the role of polymorphisms in DNA repair genes, excision repair cross‐complementation group 1 (ERCC1) with susceptibility to EOC development and tumour response to platinum‐based chemotherapy in Chinese EOC patients. Patients (n = 559) reporting to the Department of Oncology and general surgery, the First Affiliated Hospital of Kunming Medical University, were enrolled in the study. Three hundred twenty‐three healthy controls hailing from similar geographical areas without a history of cancer enrolled as healthy controls. Excision repair cross‐complementation group 1 polymorphisms (rs11615, rs3212986, rs735482, rs2336219, rs3212980, rs3212964, rs3212961 and rs2298881) were genotyped by appropriate methods. Distribution of genotypes and allele for ERCC1 polymorphisms (rs11615, rs3212986, rs735482, rs2336219, rs3212980, rs3212964, rs3212961 and rs2298881) were comparable among healthy controls and EOC patients. Interestingly, homozygous mutant and the minor allele for rs11615 and rs3212986 polymorphisms were significantly higher in nonresponder EOC patients when compared to those with a proper response to cisplatin treatment. The prevalence of other SNPs was comparable among the two treated clinical categories. Furthermore, combined genotype revealed significant association of rs11615: TT/ rs3212986: AA genotype combination with cisplatin nonresponder. Variants of rs11615, rs3212986 polymorphisms are associated with cisplatin resistance in Chinese EOC patients. Combined rs11615 and rs3212986 genotypes can be used as a predictive biomarker for platinum‐based chemotherapy outcomes.     

Excision repair cross-complementation group 1 (ERCC1) expression in advanced urothelial carcinoma patients receiving cisplatin-based chemotherapy

Cisplatin has been the cornerstone of the chemotherapy regimen for urothelial carcinoma. Excision repair cross-complementation group 1 (ERCC1) is a key component of the platinum-DNA repair machinery responsible for nucleotide excision repair. Recent reports have suggested that ERCC1 is a predictive and prognostic marker in solid cancers treated with platinum-based chemotherapy. We performed this study to determine whether or not immunohistochemical expression of ERCC1 can predict objective tumor response and cancer-specific survival in patients with advanced urothelial carcinoma treated with cisplatin-based chemotherapy. We performed a retrospective analysis of 89 patients with advanced or recurrent urothelial cancer, who had undergone treatment at Samsung Medical Center between May 2001 and August 2007. Pretherapeutic biopsy samples from 89 patients with a known tumor response were available. ERCC1 expression was assessed by immunohistochemistry. Of the 89 patients, ERCC1 expression was positive in 49 patients (55%). The overall response rate after chemotherapy was 68.5% (95% CI 54.8-74.8%). Among 61 patients who obtained a response, 27 were negative for ERCC-1 expression and 34 were positive (p = 0.61). Median duration of follow-up was 53.7 months (range 14.4-152.3 months). Progression-free survival (PFS) was 10.6 months for ERCC-1-negative patients and 8.4 months for ERCC-1-positive patients (p = 0.03); the difference in overall survival between patients with ERCC-1-negative tumors and ERCC-1-positive tumors (p = 0.73) was not statistically significant. Other than ERCC1 expression, there was no independent prognostic factor for PFS. These results suggest a negative contribution by ERCC1expression to PFS in metastatic urothelial carcinoma patients treated with cisplatin-based chemotherapy.     

肺癌组织中DNA修复基因ERCC1的表达与多环芳烃-DNA加合物的关系

目的:探讨核苷酸切除修复基因ERCC1在肺癌中的表达及其与多环芳烃(PAH)-DNA加合物的关系。方法: 用RT-PCR技术检测150例肺癌、120例癌旁肺组织、40例肺良性病变和40例正常肺组织中ERCC1基因mRNA的表达;用免疫法检测PAH-DNA加合物;分析有关暴露因素对修复基因ERCC1的表达和PAH-DNA加合物的影响,并探讨ERCC1与PAH-DNA加合物的关系。结果:30.7%(46/150)的肺癌组织和2.5%(1/40)的正常肺组织存在ERCC1基因的表达低下;吸烟可抑制ERCC1基因的表达。肺组织中PAH-DNA加合物的水平与ERCC1基因表达呈显著负相关,Spearman相关系数为-0.648,P<0.01。结论:ERCC1是参与修复DNA加合物等损伤的一个重要的核苷酸切除修复基因,其表达低下在肺癌发生中起着重要作用。     

Heterogeneity and overlaps in nucleotide excision repair disorders

Nucleotide excision repair (NER) is an essential DNA repair pathway devoted to the removal of bulky lesions such as photoproducts induced by the ultraviolet (UV) component of solar radiation. Deficiencies in NER typically result in a group of heterogeneous distinct disorders ranging from the mild UV sensitive syndrome to the cancer-prone xeroderma pigmentosum and the neurodevelopmental/progeroid conditions trichothiodystrophy, Cockayne syndrome and cerebro-oculo-facio-skeletal-syndrome. A complicated genetic scenario underlines these disorders with the same gene linked to different clinical entities as well as different genes associated with the same disease. Overlap syndromes with combined hallmark features of different NER disorders can occur and sporadic presentations showing extra features of the hematological disorder Fanconi Anemia or neurological manifestations mimicking Hungtinton disease-like syndromes have been described. Here, we discuss the multiple functions of the five major pleiotropic NER genes (ERCC3/XPB, ERCC2/XPD, ERCC5/XPG, ERCC1 and ERCC4/XPF) and their relevance in phenotypic complexity. We provide an update of mutational spectra and examine genotype-phenotype relationships. Finally, the molecular defects that could explain the puzzling overlap syndromes are discussed.     

Proficient deoxyribonucleic acid repair of methylation damage in hamster ERCC-gene mutants

Three major pathways, nucleotide excision repair (NER), base excision repair (BER) and O⁶-methylguanine–DNA methyltransferase (MGMT), are responsible for the removal of most adducts to DNA and thus for the survival of cells influenced by deoxyribonucleic acid (DNA) adduct-forming chemicals. We have evaluated host cell reactivation and cell survival of wild type Chinese hamster ovary cells and of mutants in the NER-genes ERCC1, ERCC2, and ERCC4 after treatment with the methylating compounds dimethylsulfate and methylnitrosourea. No effect of the three genes could be demonstrated, i.e., survival and host cell reactivation after methylation damage in the mutants and the wild type cells were similar. Gene-specific repair experiments confirmed the proficient removal of methyl lesions. We conclude that the three nucleotide excision repair genes are immaterial to the repair of methylation damage. This suggests that NER does not play a role in the removal of methylation in mammalian cells and that BER and MGMT are responsible for the survival of such cells, when they are challenged with methylation of DNA.     

BRCA1 and p53: compensatory roles in DNA repair

The BRCA1 breast cancer susceptibility gene has been implicated in many cellular processes, yet its specific mechanism of tumor suppression remains unclear. BRCA1 plays a role in several DNA repair pathways including nucleotide excision repair (NER). Loss of the p53 tumor suppressor gene, a key regulator of NER, is an important and necessary event in the pathogenesis of BRCA1-mutated tumors. Here we discuss the role of BRCA1 and NER in breast cancer and the interactions of BRCA1 with p53 in breast tumorigenesis and suggest approaches for risk assessment and chemotherapeutic management of BRCA1-related breast cancer.     

Expression of ERCC1 and class IIIβ tubulin for predicting effect of carboplatin/paclitaxel in patients with advanced inoperable non‐small cell lung cancer

It was recently reported that expression of excision repair cross‐complementation group 1 (ERCC1), a DNA repair protein, predicts sensitivity to platinum‐based chemotherapy drugs. Microtubule inhibitors such as paclitaxel demonstrate anticancer effects by inhibiting spindle fibers during mitosis; and class IIIβ tubulin (IIIβ tubulin), a microtubule component, is thought to be resistant to microtubule inhibitors. The purpose of the present study was to examine the correlation between prognosis and expression of these proteins using biopsy tissues obtained from 40 patients with advanced inoperable non‐small cell lung cancer who had been treated with carboplatin plus Taxol. On immunostaining 27 patients (68%) were positive for ERCC1 and 22 (55%) were positive for IIIβ tubulin. The prognosis of the ERCC1‐negative group was significantly better than that for the ERCC1‐positive group (P= 0.014). As for IIIβ tubulin, the prognosis for the negative group was also significantly better than that for the positive group (P= 0.025). Multivariate analysis showed that the expression of ERCC1 was an independent predictor of prognosis (hazard ratio: 3.485; 95% confidence interval: 1.123–10.818, P= 0.031). It was concluded that determination of the expression of these proteins is useful to predict the effects of platinum‐based anticancer drugs.     

TFPI‐2 Downregulates Multidrug Resistance Protein in 5‐FU‐Resistant Human Hepatocellular Carcinoma BEL‐7402/5‐FU Cells

Tissue factor pathway inhibitor‐2 (TFPI‐2) is known to induce apoptosis and to suppress tumor metastasis in several types of cancer cells. However, there is little known about its reversal effect on chemoresistant tumor cells. This study investigated the effect of TFPI‐2 in 5‐fluorouracil (5‐FU)‐resistant human hepatocellular cancer BEL‐7402/5‐FU cells in vitro. We constructed TFPI‐2 overexpression BEL‐7402/5‐FU cell lines and explored resistance index (RI) of 5‐FU, function of the P‐glycoprotein (P‐gp) efflux pump, and the mRNA and protein expression of drug resistance gene, including multidrug resistance gene (MDR1), lung‐resistance protein (LRP), multidrug resistance‐associated protein (MRP1), glutathione‐S‐transferase‐π (GST‐π), excision repair cross‐complementing gene 1 (ERCC1), and p38 phosphorylation. We found that TFPI‐2 improved the RI of 5‐FU and inhibited P‐gp function. Western blotting and real‐time PCR revealed that TFPI‐2 also decreased mRNA and protein expression of MDR1, LRP, MRP1, GST‐π, and ERCC1, whereas p38 phosphorylation was increased. We considered that TFPI‐2 reduces 5‐FU resistance in BEL‐7402/5‐FU cells, and the mechanism appears to involve p38‐mediated downregulation of drug resistance gene expression such as MDR1, LRP, MRP1, GST‐π, and ERCC1. Anat Rec, 2013. © 2012 Wiley Periodicals, Inc.     

A common polymorphism in the 5′ UTR of ERCC5 creates an upstream ORF that confers resistance to platinum-based chemotherapy

We show that a common polymorphic variant in the ERCC5 5′ untranslated region (UTR) generates an upstream ORF (uORF) that affects both the background expression of this protein and its ability to be synthesized following exposure to agents that cause bulky adduct DNA damage. Individuals that harbor uORF1 have a marked resistance to platinum-based agents, illustrated by the significantly reduced progression-free survival of pediatric ependymoma patients treated with such compounds. Importantly, inhibition of DNA-PKcs restores sensitivity to platinum-based compounds by preventing uORF1-dependent ERCC5 expression. Our data support a model in which a heritable 5′ noncoding mRNA element influences individuals’ responses to platinum-based chemotherapy.     

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.     

Genetic variability of DNA repair mechanisms influences chemotherapy outcome of gastric cancer

Genetic variability of DNA repair mechanisms influences chemotherapy treatment outcome of gastric cancer. We conducted a cohort study to investigate the role of ERCC1-ERCC2 gene polymorphisms in the chemotherapy response and clinic outcome of gastric cancer. Between March 2011 and March 2013, 228 gastric patients who were newly diagnosed with histopathology were enrolled in our study. Genotypes of ERCC1 rs11615, rs3212986, rs2298881 and ERCC2 rs3212986 were conducted by polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) assay. We found that individuals carrying TT genotype of ERCC1 rs11615 and CC genotype of ERCC1 rs2298881 were associated with better response to chemotherapy and longer survival time of gastric cancer. Moreover, individuals with AA genotype of ERCC2 rs1799793 were correlated with shorter survival of gastric cancer. In conclusion, ERCC1 rs11615, rs2298881 and ERCC2 rs1799793 polymorphism play an important role in the treatment outcome of gastric cancer.     

Early-onset nucleotide excision repair disorders with neurological impairment: Clues for early diagnosis and prognostic counseling

Nucleotide excision repair associated diseases comprise overlapping phenotypes and a wide range of outcomes. The early stages still remain under-investigated and underdiagnosed, even although an early recognition of the first symptoms is of utmost importance for appropriate care and genetic counseling. We systematically collected clinical and molecular data from the literature and from newly diagnosed NER patients with neurological impairment, presenting clinical symptoms before the age of 12 months, including foetal cases. One hundred and eighty-five patients were included, 13 with specific symptoms during foetal life. Arthrogryposis, microcephaly, cataracts, and skin anomalies are the most frequently reported signs in early subtypes. Non ERCC6/CSB or ERCC8/CSA genes are overrepresented compared to later onset cohorts: 19% patients of this cohort presented variants in ERCC1, ERCC2/XPD, ERCC3/XPB or ERCC5/XPG. ERCC5/XPG is even the most frequently involved gene in foetal cases (10/13 cases, [4/7 families]). In this cohort, the mutated gene, the age of onset, the type of disease, severe global developmental delay, IUGR and skin anomalies were associated with earlier death. This large survey focuses on specific symptoms that should attract the attention of clinicians towards early-onset NER diagnosis in foetal and neonatal period, without waiting for the completeness of classical criteria.     

Genetic variability of genes in NER pathway influences the treatment outcome of gastric cancer

We performed a study to investigate the role of ERCC1, ERCC2, ERCC5, XPA and XPC polymorphisms from perspective of the whole NER pathway in the prognosis of gastric cancer. A total of 410 gastric cancer patients were recruited between January 2010 and December 2011. Restriction fragment length polymorphism-polymerase chain reaction (RFLP-PCR) was used to analyze genotypes of ERCC1 rs11615 and rs3212986, ERCC2 rs13181 and s1799793, ERCC5 rs17655, XPA rs1800975 and XPC rs2228001. Our study found that carriers of ERCC1 rs3212986 TT genotype showed significantly favorable survival than wide-type GG genotype in multivariate analysis (OR=6.38, 95% CI=2.54-19.03), and patients with variant CC genotype of ERCC2 rs13181 exhibited better response to chemotherapy than those with AA genotype (OR=2.21, 95% CI=1.17-4.25). By Cox proportional hazards model, patients with variant TT genotype of ERCC1 rs3212986 exhibited longer PFS and OS than those who had GG genotype (for PFS, HR=0.37, 95% CI=0.17-0.75; for OS, HR=0.36, 95% CI=0.13-0.87). For ERCC2 rs13181 polymorphism, carriers with CC genotype demonstrated significantly increased hazards of progression of disease and death in multivariate model (for PFS, HR=0.48, 95% CI=0.26-0.88; for OS, HR=0.44, 95% CI=0.20-0.91). In conclusion, our finding suggests that ERCC1 rs3212986 and ERCC2 rs13181 gene polymorphism could influence the response to chemotherapy and clinical outcome of gastric cancer.