Role of ERCC1 expression in colorectal adenoma-carcinoma sequence and relation to other mismatch repair proteins expression, clinicopathological features and prognosis in mucinous and non-mucinous colorectal carcinoma

Background: There are several DNA repair pathways that protect cellular DNA from injury, such as nucleotide excision repair (NER) and mismatch repair (MMR). The protein product of the excision repair cross-complementation group 1 (ERCC1) gene plays a pivotal role in NER. The exact relationship between MMR proteins and ERCC1 is not well known in colorectal carcinoma (CRC). Aim of the Study: To investigate expression of ERCC1 and MMR proteins in colorectal mucinous carcinoma (MA) and non-mucinous carcinoma (NMA) using tissue microarray technique. Material and Methods: We studied tumor tissue specimens from 150 patients with colorectal mucinous (MA) and non-mucinous adenocarcinoma (NMA). Tissue microarrays were constructed using modified mechanical pencil tips technique and immunohistochemistry for ERCC1, MLH1, MSH2, MSH6, and PMS2. Results: NMA showed a significantly more frequent aberrant cytoplasmic expression than MA while MA showed a more frequent intact nuclear expression than NMA. There were no significant differences between the NMA and MA groups in the expression of MMR proteins. In NMA cases, ERCC1 expression was significantly related to MMR status while was not significantly related in MA cases. ERCC1 expression was not significantly related to overall and disease-free survival in both NMA and MA groups. Conclusion: this study is the first to investigate the relation between MMR status and ERCC1 expression in colorectal MA and NMA. ERCC1 expression was significantly related to MMR status only in NMA cases. Hence, the current study emphasizes that further research about the relation between various DNA repair pathways is needed.

Mechanisms of miR-503 inhibiting radio-resistance of esophageal squamous cell carcinoma cells by targeting ERCC1 / 中国肿瘤生物治疗杂志

@# Objective: To investigate the mechanism of miR-503 modulates radio-resistance of esophageal squamous cell carcinoma (ESCC) by targeting excision-repair cross-complementing 1 (ERCC1). Methods: The expression level of miR-503 in radio-resistant ESCC tumor tissues and KYSE140 and KYSE140R cells was detected by qPCR. The miR-503 mimic, miR-503 inhibitor or si-ERCC1 was transfected into KYSE140 and KYSE140R cells.After radiation treatment, the colony formation assay and CCK-8 assay were used to detect the proliferation of KYSE140R cells. Flow cytometry was used to detect apoptosis of KYSE140R cells. WB was used to detect changes in protein expression of ERCC1. Dual luciferase reporter gene assay was used to validate the targeting relationship between miR-503 and ERCC1. Results: The expression level of miR-503 was down-regulated in radio-resistant tissues and ESCC cell lines (all P<0.01). Over-expression of miR-503 significantly inhibited cell proliferation and promoted apoptosis of KYSE140R cells (all P<0.01). Dual-luciferase reporter assay validated that ERCC1 was a target gene of miR-503, and miR-503 negatively regulated the expression of ERCC1. Over-expression of miR-503 significantly down-regulated the expression of ERCC1 in KYSE140 and KYSE140R cells (both P<0.01), inhibited cell proliferation (both P<0.01), but significantly increased apoptosis rate (all P<0.01); knockdown of ERCC1 exhibited a similar effect, while knockdown of both ERCC1 and miR-503 reversed the above effects. Conclusion: Over-expression of miR-503 up-regulated the radio-sensitivity of KYSE140R cells by targeting ERCC1.

Immunohistochemistry Biomarkers Predict Survival in Stage II/III Gastric Cancer Patients: From a Prospective Clinical Trial / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: Identification of biomarkers to predict recurrence risk is essential to improve adjuvant treatment strategies in stage II/III gastric cancer patients. This study evaluated biomarkers for predicting survival after surgical resection. MATERIALS AND METHODS: This post-hoc analysis evaluated patients from the CLASSIC trial who underwent D2 gastrectomywith orwithout adjuvant chemotherapy (capecitabine plus oxaliplatin) at the Yonsei Cancer Center. Tumor expressions of thymidylate synthase (TS), excision repair cross-complementation group 1 (ERCC1), and programmed death-ligand 1 (PD-L1) were evaluated by immunohistochemical (IHC) staining to determine their predictive values. RESULTS: Among 139 patients, IHC analysis revealed high tumor expression of TS (n=22, 15.8%), ERCC1 (n=23, 16.5%), and PD-L1 (n=42, 30.2%) in the subset of patients. Among all patients, high TS expression tended to predict poor disease-free survival (DFS; hazard ratio [HR], 1.80; p=0.053), whereas PD-L1 positivity was associated with favorable DFS (HR, 0.33; p=0.001) and overall survival (OS; HR, 0.38; p=0.009) in multivariate Cox analysis. In the subgroup analysis, poor DFS was independently predicted by high TS expression (HR, 2.51; p=0.022) in the adjuvant chemotherapy subgroup (n=66). High PD-L1 expression was associated with favorable DFS (HR, 0.25; p=0.011) and OS (HR, 0.22; p=0.015) only in the surgery-alone subgroup (n=73). The prognostic impact of high ERCC1 expression was not significant in the multivariate Cox analysis. CONCLUSION: This study shows that high TS expression is a predictive factor for worse outcomes on capecitabine plus oxaliplatin adjuvant chemotherapy, whereas PD-L1 expression is a favorable prognostic factor in locally advanced gastric cancer patients.

Radiotherapy modulates expression of EGFR, ERCC1 and p53 in cervical cancer

Cervical cancer is a public health problem and the molecular mechanisms underlying radioresistance are still poorly understood. Here, we evaluated the modulation of key molecules involved in cell proliferation, cell cycle and DNA repair in cervical cancer cell lines (CASKI and C33A) and in malignant tissues biopsied from 10 patients before and after radiotherapy. The expression patterns of epidermal growth factor receptor (EGFR), excision repair cross-complementation group 1 (ERCC1) and p53 were evaluated in cancer cell lines by quantitative PCR and western blotting, and in human malignant tissues by immunohistochemistry. The mutation status of TP53 gene was evaluated by direct sequencing. Among cell lines, absent or weak modulations of EGFR, ERCC1 and p53 were observed after exposure to 1.8 Gy. Conversely, increased expressions of p53 (5/10 patients; P=0.0239), ERCC1 (5/10 patients; P=0.0294) and EGFR (4/10 patients; P=0.1773) were observed in malignant tissues after radiotherapy with the same radiation dose. TP53 mutations were found only in one patient. Here we show that a single dose of radiotherapy induced EGFR, ERCC1 and p53 expression in malignant tissues from cervical cancer patients but not in cancer cell lines, highlighting the gap between in vitro and in vivo experimental models. Studies on larger patient cohorts are needed to allow an interpretation that an upregulation of p53, EGFR and ERCC1 may be part of a radioresistance mechanism.

Expression and its clinical significance of ERCC1 in stage Ⅱ colorectal carcinoma / 西安交通大学学报(医学版)

Objective To investigate the expression and clinical significance of excision repair cross complementing gene 1 (ERCC1 )in colorectal carcinoma of stage Ⅱ and its clinical significance.Methods We collected 56 cases of stage Ⅱ postoperative colorectal carcinoma tissue and detected ERCC1 expression with immunofluorescence technique.Statistical analysis was made with SPSS13.0 software.Results ERCC1 expression was obviously lower in stage II postoperative colorectal carcinoma tissue than in normal tissue (P =0.01).In cancer tissue,ERCC1 expression in patients with relapse or metastasis was significantly lower than in those without (P =0.002);ERCC1 expression in patients with T3 was significantly higher than those with T4 (P = 0.044).ERCC1 expression had a positive correlation with the overall survival (OS)and disease-free survival (DFS)(both P =0.000).In the group of high ERCC1 expression patients,five-year OS rate and DFS rate between patients who had received oxaliplatin-based adjuvant chemotherapy and those who did not have no significant difference (P =0.351;P =0.465).In the group of low ERCC1 expression patients,five-year OS rate and DFS rate of patients who received oxaliplatin-based adjuvant chemotherapy were significantly higher than those of patients who did not (P =0.015,P =0.02).ERCC1 (P =0.031 )and relapse or metastasis (P =0.009)were independent factors affecting OS;relapse or metastasis (P =0.000)was an independent factor affecting DFS.Conclusion ERCC1 is an independent factor affecting the OS of patients with stage Ⅱ colorectal carcinoma.Patients with low ERCC1 expression have poor prognosis,but they can benefit from oxaliplatin-based adjuvant chemotherapy.

Patients with advanced gastric cancer in Qinghai Tibetan TSER, ERCC1, polymorphism and mRNA significance / 实用医学杂志

Objective To discuss progress in Qinghai Tibetan Thymidylate synthase enhancer in patients with gastric cancer (TSER),ERCC1 polymorphism of genes,gene expression and mRNA studies.Methods 210 cases of advanced gastric cancer were enrolled as required to complete the treatment and follow-up.TSER,ERCC 1 gene polymorphism were tested using PCR-RFLP method.Analysis of gastric cancer is based on the results of gene polymorphism and clinical pathological factors in relations.The expression of ERCC1 mRNA was detected by RTPCR,and tracking access after treatment.Analyzing the relationship among ERCC1 mRNA expression,clinical treatment of overall survival,total response rates and gene polymorphism.Results In patients with advanced gastric C/C in Qinghai ERCC1 gene frequency was 54.2％,C/T frequency was 42.7％,T/T ERCC1 gene frequency was 5.6％.ERCC1 mRNA expression and clinical effect in the treatment of pathological factors were not related,ERCC1 mRNA and gene ERCC1 polymorphism had no relevance.Conclusions Progress in Qinghai Tibetan TSER gene is highly expressed type 3R/3R in patients with gastric cancer.ERCC 1 gene polymorphisms with type C/ C is overexpressed.ERCC1,TSER gene polymorphism and clinicopathologic parameters in advanced gastric is not related.Extension of Tibetan ERCC1 mRNA in gastric cancer patients expression has no association with ERCC1 gene polymorphism.

Clinical expression of P53,Livin and PARP in the epithelial ovarian cancer and its impact in the chemotherapy resistance and clinical prognosis / 中国生化药物杂志

Objective To explore the clinical expression of P53, Livin and PARP in the epithelial ovarian cancer and its correlation with the chemotherapy resistance and clinical prognosis.Methods 74 specimen of epithelial ovarian cancer confirmed from January 2009 to June 2011 in our gynecology department were selected.During the follow-up visit, the subjects were divided into chemotherapy sensitivity group and chemotherapy resistance group according to the recurrence cases, the clinical expression and survival rate for two groups were compared, the influence factors of survival time were analyzed.Results The positive rate of P53, Livin and PARP for chemotherapy sensitivity group was 47.1%, 56.9%and 52.9%;the positive rate for chemotherapy resistance group was 73.9%, 95.7% and 95.7%,the diyforences were significant(P<0.05).After 1, 3 and 5 years of treatment, the survival rate for chemotherapy sensitivity group was 100.0%, 82.4% and 66.7%,The survival rate for chemotherapy resistance group was 87.0%, 26.1% and 8.7%,the diyforences were significant(P<0.05).Based on the Cox regression model, the influence factors of the patient's age, pathological differentiation degree, clinical staging and chemotherapy sensitivity were introduced.It was known that the patient's survival time was greatly influenced by clinical staging and chemotherapy sensitivity (P<0.05).Conclusion For patients with epithelial ovarian cancer, the expression of P53, Livin and PARP is correlated with chemotherapy resistance.Therefore, the clinical effect is predictable, for patients with higher expression, the personalized therapy can improve the patient's prognosis.

A pilot study of the ERCC1 and XPF genes in forensic age estimation / 中国法医学杂志

Objective The aim of this study is to detect the mRNA and protein expression levels of ERCC1 and XPF genes among different age groups of healthy Chinese Han individuals,and to analyze the correlation between the mRNA and protein expression levels andthe age of individuals in order to find new molecular markers for forensic age estimation.Methods Peripheral blood samples were obtained from 150 unrelated healthy Chinese Han individuals.The plasma was centrifuged from the whole blood by gradient centrifugation,and the totalRNA was extractedwithTrizol fromperipheral blood mononuclear cells(PBMCs).Real-time quantitative reverse transcription polymerase chain reaction (RT-qPCR) was used to quantitatively analyze the mRNA relative expression levels of ERCC1and XPF in PBMCs.Enzyme linked immunosorbent assay (ELISA) was used to quantitatively analyze the protein expression levels of ERCC1and XPF in plasma.Results There were no significant differences in the mRNA relative expression levels of ERCC1 and XPF in PBMCs between males and females(P＞0.05).Significant differences were found in the mRNA relative expression levels of ERCC1 and XPF between different age groups (P＜0.05).Regression analysis showed thatthe mRNA relative expression levels of ERCC1 and XPF were both negatively correlated with age.The correlation coefficients(r) were-0.578 and-0.844,respectively.When the age was used as independent variable(x) and the mRNA expression relative level as dependent variable (y),the fitting curveswere Y=3.3E-5X2-0.0261X+1.9175 (R2=0.3244,P＜0.01),Y=0.0003X2-0.0459X+2.0439 R2=0.729,P＜0.01),respectively.There were no significant differences inthe protein expression levels of ERCC1 and XPF in plasma between different age groups or genders (P＞0.05).Conclusion The mRNA relative expression levels of ERCC1 and XPF in PBMCsdeclined with the increase of age,however,the protein expression levels in plasma were unrelated to age.ERCC 1 and XPF genes can be used asnew molecular markers for forensic age estimation,so as to providetheoretical basis for establishing the mathematical model of ERCC1/XPF genesin concern ofindividual ages.

Relationship between expression of ERCC1 and prognosis of smoking patients with advanced NSCLC / 安徽医科大学学报

Objective To investigate the expression of ERCC1 in smoking patients with advanced non-small cell lung cancer(NSCLC) and its relationship with clinical features and prognosis.Methods The expression of ERCC1 was detected in 96 patients with advanced NSCLC by PCR assay.The clinicopathologic factors, treatment effect and survival time were observed.Results The expression of ERCC1 was related to smoking index(P=0.029), but it was not related to other clinicopathological factors.The patients with low expression of ERCC1 had better response rate and median survival time when compared to those with high expression patients.The difference was statistically significant(P=0.001,P<0.01).Conclusion ERCC1 expression is associated with smoking index and the patients with low expression of ERCC1 shows higher chemotherapy efficiency and longer median survival than patients with high expression, which indicates that detection of ERCC1 may be a useful parameter in evaluating the therapeutic effect and prognosis of smoking patients with advanced NSCLC.

Expression and its clinical significance of ERCC1 in stage Ⅱ colorectal carcinoma / 西安交通大学学报(医学版)

Objective To investigate the expression and clinical significance of excision repair cross complementing gene 1 (ERCC1 )in colorectal carcinoma of stage Ⅱ and its clinical significance.Methods We collected 56 cases of stage Ⅱ postoperative colorectal carcinoma tissue and detected ERCC1 expression with immunofluorescence technique.Statistical analysis was made with SPSS13.0 software.Results ERCC1 expression was obviously lower in stage II postoperative colorectal carcinoma tissue than in normal tissue (P =0.01).In cancer tissue,ERCC1 expression in patients with relapse or metastasis was significantly lower than in those without (P =0.002);ERCC1 expression in patients with T3 was significantly higher than those with T4 (P = 0.044).ERCC1 expression had a positive correlation with the overall survival (OS)and disease-free survival (DFS)(both P =0.000).In the group of high ERCC1 expression patients,five-year OS rate and DFS rate between patients who had received oxaliplatin-based adjuvant chemotherapy and those who did not have no significant difference (P =0.351;P =0.465).In the group of low ERCC1 expression patients,five-year OS rate and DFS rate of patients who received oxaliplatin-based adjuvant chemotherapy were significantly higher than those of patients who did not (P =0.015,P =0.02).ERCC1 (P =0.031 )and relapse or metastasis (P =0.009)were independent factors affecting OS;relapse or metastasis (P =0.000)was an independent factor affecting DFS.Conclusion ERCC1 is an independent factor affecting the OS of patients with stage Ⅱ colorectal carcinoma.Patients with low ERCC1 expression have poor prognosis,but they can benefit from oxaliplatin-based adjuvant chemotherapy.

ERCC1 Expression-Based Randomized Phase II Study of Gemcitabine/Cisplatin Versus Irinotecan/Cisplatin in Patients with Advanced Non-small Cell Lung Cancer / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: We evaluated the clinical utility of excision repair cross-complementation group 1 (ERCC1) expression as a predictive biomarker for platinum-based chemotherapy in advanced non-small cell lung cancer (NSCLC). MATERIALS AND METHODS: Eligible patients were randomly assigned to the GP (gemcitabine 1,250 mg/m² on days 1 and 8, and cisplatin 75 mg/m² on day 1 every 3 weeks) or IP (irinotecan 65 mg/m² and cisplatin 30 mg/m² on days 1 and 8 every 3 weeks) arm. The primary goal of this study was to compare the response rate (RR) of the GP and IP arms according to the ERCC1 expression level. RESULTS: A total of 279 patients were randomly assigned to the GP (n=139) and IP (n=140) arms, among which 63% were ERCC1-positive and 268 patients were assessable for the RR. The GP and IP arms did not differ significantly with respect to the RR (29.8% vs. 27.0%, respectively; p=0.082), median progression-free survival (PFS; 4.5 months vs. 3.9 months, respectively; p=0.117), and overall survival (OS; 16.5 months vs. 16.7 months, respectively; p=0.313). When comparing the efficacy between the ERCC1-positive and ERCC1-negative groups, there was no significant difference in the RR (GP, 28.2% vs. 32.6%, respectively, p=0.509; IP, 30.2% vs. 21.6%, respectively, p=0.536), median PFS (GP, 4.6 months vs. 5.0 months, respectively, p=0.506; IP, 3.9 months vs. 3.7 months, respectively, p=0.748), or median OS (GP, 18.6 months vs. 11.9 months, respectively, p=0.070; IP, 17.5 months vs. 14.0 months, respectively, p=0.821). CONCLUSION: Immunohistochemical analysis of the ERCC1 expression level did not differentiate the efficacy of platinum-based chemotherapy in advanced NSCLC.

Influence on radiosensitivity of lung glandular cancer cells when ERCC1 gene silenced by targeted siRNA

Objective To identify the influence on radiosensitivity of lung glandular cancer cells when excisions repair cross-complementing group1 (ERCC1) gene was silenced by targeted siRNA. Methods siRNA which targeting to ERCC1 and control siRNA was designed and synthesized. The human lung glandular cancer SPC-A-1 cells was transfected. A total of 56 nude mice were divided into two groups, and two kinds of SPC-A-1 cells were transplanted to armpit of right forelimb, to establish the nude mice subcutaneous xenotransplanted tumor model of human lung glandular cancer cells. After the tumor was developed, the nude mice were randomly divided into four groups and accepted different doses of X-Ray radiation, then the change of tumor volume, survival time of mice in every group were recorded and the average lifetime was calculated. Twenty-one days later of X-ray experiment, two mice were taken and killed in each group and the tumors organizations were stripped. The cell apoptosis rate and cell cycle distributions were obtained by FCM (flow cytometry). Results The volume of tumor which ERCC1 gene was silenced was less than single irradiation group after X-ray irradiation, and the growth speed was slower and the lifetime of mice was lengthened as well (P < 0.05). The cells apoptosis rate and the rate of G

The relationship on polymorphisms of ERCC1-4533/8092 and the susceptibility of hepatocellular carcinoma / 国际检验医学杂志

Objective To investigate the relationship on the excision repair cross complementing gene 1(ERCC1)‐4533/8092 site single nucleotide polymorphisms(SNPs) and the susceptibility to hepatocellular carcinoma(HCC) in Guangxi Zhuang population . Methods Polymerase chain reaction‐restriction fragment length polymorphism (PCR‐RFLP) method was used to detect the ER‐CC1‐4533/8092 gene polymorphism in 88 cases with primary liver cancer and 82 cases of normal controls .Results There was no difference in the frequency distribution of ERCC1‐4533 in the case group and the control group ,the frequency distribution of the ERCC1‐8092 in the case group and the control group was different(P< 0 .05) .Compared with ERCC1‐8092 CC ,ERCC1‐C8092 CA/AA had higher risk of primary hepatocellular carcinoma(CA :OR=2 .556 ,95% CI:1 .345 -4 .855;AA :OR= 8 .667 ,95% CI:1 .000-75 .092) .ERCC1‐8092 C allele as a reference ,ERCC1‐8092 A allele can increase the risk of primary liver cancer (OR=2 .387 ,95% CI:1 .428-3 .992) .Conclusion The genetic polymorphisms of ERCC1‐8092 sites are associated with susceptibility to hepatocellular carcinoma in Guangxi Zhuang population .

ERCC1 expression in advanced breast cancer and its relationship with cisplatin resistance / 中华内分泌外科杂志

Objective To investigate ERCC1 expression in advanced breast cancer and its relationship with cisplatin resistance. Methods ERCC1 expression in 50 cases of advanced breast cancer was measured by RT-QPCR. The chemotherapy (CAF) was given. Gemcitabine and cisplatin were given because of metastasis. Results The expression of ERCC1 has no relationship with age, lymph node metastasis, clinicl stage, histologi-cal grade or human epidermal growth factor receptor-2 (HER2) expression. The effective rate was 18.8% (3/16) for ERCC1 high-expressed patients and 79.4%(27/34)for ERCC1 low-expressed patients in terms of cisplatin chemotherapy. The sensitity for cisplatin chemotherapy was high for patients with low ERCC1 expression and it was low for patients with high ERCC1 expression. The effective rate (complete remission+partial remission), and ineffective rate (stable disease+progressive disease) between the two had statastical significance (P<0.001). Con-clusions ERCC1 low-expressed patients can benefit from cisplatin. ERCC1 can be used as a moleculer marker for predicting chemotherapy efficacy in breast cancer.

Influence on radiosensitivity of lung glandular cancer cells when ERCC1 gene silenced by targeted siRNA

OBJECTIVE@#To identify the influence on radiosensitivity of lung glandular cancer cells when excisions repair cross-complementing group1 (ERCC1) gene was silenced by targeted siRNA.@*METHODS@#siRNA which targeting to ERCC1 and control siRNA was designed and synthesized. The human lung glandular cancer SPC-A-1 cells was transfected. A total of 56 nude mice were divided into two groups, and two kinds of SPC-A-1 cells were transplanted to armpit of right forelimb, to establish the nude mice subcutaneous xenotransplanted tumor model of human lung glandular cancer cells. After the tumor was developed, the nude mice were randomly divided into four groups and accepted different doses of X-Ray radiation, then the change of tumor volume, survival time of mice in every group were recorded and the average lifetime was calculated. Twenty-one days later of X-ray experiment, two mice were taken and killed in each group and the tumors organizations were stripped. The cell apoptosis rate and cell cycle distributions were obtained by FCM (flow cytometry).@*RESULTS@#The volume of tumor which ERCC1 gene was silenced was less than single irradiation group after X-ray irradiation, and the growth speed was slower and the lifetime of mice was lengthened as well (P < 0.05). The cells apoptosis rate and the rate of G2/M cells which ERCC1 gene was silenced were higher than the same dose control group and the rate of G1 cells were lower, which indicated that the cells could be stopped at G2/M point, the cell proliferation was inhibited, the cell apoptosis was promoted and the radiation sensitivity was improved after the ERCC1 was silenced.@*CONCLUSIONS@#The radiation sensitivity of lung glandular tumor could be improved after the ERCC1 gene was silenced by siRNA.

Correlation of EGFR mutation with ERCC1 and TYMS mRNA expression in non-small cell lung cancer / 重庆医学

Objective To investigate whether EGFR gene mutations are correlated with the gene expression of ERCC1 and TYMS in non-small-cell lung cancer .Methods Collected February to December 2013 of non-small cell lung cancer(NSCLC) pa-tients eligible for enrolled 97 patients ,tumor tissue specimens obtained by intraoperative cut or puncture ,Gene expression of ERCC1 and TYMS were determined by branched-DNA liquid chip ,while somatic mutations in EGFR(E18 ,E19 ,E20 ,E21) gene were detec-ted by xTAG-liquid chip;And analysis of EGFR gene mutation associated with ERCC1 ,TYMS mRNA expression .Results Totally 29 cases of EGFR mutation were detected in all 97 specimens ,with a mutation rate of 30% (29/97) ,and a relatively high detection rate was observed in female ,adenocarcinoma and non-smoking patients(P0 .05) .Conclusion In NSCLC tissues ,EGFR mutation is relevant to the expression of ERCC1 but irrelevant to the expression of TYMS .

Metformin reverses drug-resistance of ovarian cancer cells to cisplatin by inhibiting p38 mitogen-activated protein kinase signaling pathway / 肿瘤

Objective: To investigate whether metformin can reverse drug-resistance of ovarian cancer cells to cisplatin, and explore its underlying mechanism. Methods: Cisplatin-resistant ovarian cancer cells C1 3K and CP70 were used in this study. The small interfering RNAs (siRNAs) targeting excision repair cross-complemention 1 (ERCC1) gene were synthesized and transfected into C1 3K and CP70 cells, respectively. The change of cisplatin-resistance of C1 3K and CP70 cells was detected by cell count kit-8 (CCK-8) assay after metformin treatment and ERCC1 siRNA transfection. The expressions of ERCC1 mRNA in C13K and CP70 cells treated with different concentrations of metformin were detected by real-time fluorescent quantitative-PCR. The activation of AMP-activated protein kinase (AMPK) and suppression of p38 mitogen-activated protein kinase (p38MAPK) in C1 3K and CP70 cells after metformin treatment were evaluated by Western blotting. Then the expression level of ERCC1 protein in C1 3K and CP70 cells treated with metformin (combined with Compound C, a blocking agent of AMPK signaling pathway, or p38MAPK siRNA transfection) or SB203580 (an inhibitor of p38MAPK signaling pathway) was detected by Western blotting. Results: Metformin could reverse drug-resistance of C13K and CP70 cells to cisplatin (P 0.05). Conclusion: Metformin may reverse the drug-resistance of cisplatin-resistant ovarian cancer cells to cisplatin. This effect of metformin may be due to the inhibition of p38MAPK signaling pathway and the downregulation of ERCC1 gene expression in ovarian cancer cells.

The research on the change of chemosensitivity of geiftinib-resistant lung adenocarcinoma cell caused byEGFR-T790M mutation / 中国癌症杂志

Background and purpose:Chemotherapy is an alternative treatment option, which could still get a therapeutic effect, when the EGFR-TKI treatment of non-small cell lung cancer failed. Studies have shown that RR, TYMS, ERCC1 and TUBB3 have respectively relationship with chemosensitivity of gemcitabine, pemetrexed, platinum-based drugs and microtubule-based chemotherapy drugs.The expression levels of these molecular markers can predict the sensitivity of these chemotherapy drugs. The patients with RRMI, TS, ERCC1 and TUBB3 higher expression have reduced chemosensitivity, and lower expression have increased sensitivity. The purpose of this study was to explore the sensitivity of tumor cell lines with acquired resistance to geiftinib caused byEGFR-T790M mutation to cisplatin, gemcitabine, pemetrexed, vinorelbine, paclitaxel and docetaxel.Methods:MTT assay was used to detect the IC50 values of cisplatin, gemcitabine, vinorelbine, paclitaxel and docetaxel, pemetrexed to PC9 and PC9/GR cells, and to explore the chemosensitivity of lung adenocarcinoma cells to these chemotherapy drugs; Luminex method was used respectively to detect the expression levels of ERCC1 mRNA, TUBB3 mRNA, TS mRNA, and RRM1 mRNA in PC9 and PC9/GR cells. Western blot was used to detect the protein expression levels of ERCC1, TUBB3, TS and RRM1 in PC9 and PC9/GR cells.Results: The IC50 values of cisplatin, gemcitabine and pemetrexed to PC9/GR cells were signiifcantly higher than those to PC9 cells (P<0.05), while the IC50 values of vinorelbine, paclitaxe and docetaxel to PC9/GR cells were signiifcantly decreased (P<0.05). Luminex method showed the expressions of ERCC1 mRNA, TS mRNA and RRM1 mRNA in PC9/GR cells were signiifcantly increased than those in PC9 cells (P<0.05), while the expression of TUBB3 mRNA was signiifcantly decreased (P<0.05). Western blot method showed the expressions of TUBB3, TS and RRM1 protein in PC9/GR cells were signiifcantly increased than those in PC9 cells (P<0.05), while TUBB3 protein expression in PC9/GR cells was signiifcantly decreased (P<0.05). Western blot method analysis result showed that the expressions of TUBB3, TS and RRM1 protein in PC9/GR cells were significantly increased than those in PC9 cells (P<0.05), while TUBB3 protein expression in PC9/GR cells was signiifcantly decreased (P<0.05). Conclusion:The chemosensitivity of lung adenocarcinoma with EGFR-T790M mutation is changed. It has decreased sensitivity to cisplatin, gemcitabine, pemetrexed and increased sensitivity to vinorelbine, paclitaxel and docetaxel. The reason of the change of chemosensitivity of geiftinib-resistant lung adenocarcinoma cell maybe related to the changes of ERCC1 mRNA, RRM1 mRNA and TS mRNA and their protein expressions.

EGFR gene mutation status, ERCC1 and Ki-67 protein expression in non-small cell lung cancer and relationship with clinicopathologic features / 临床与实验病理学杂志

Purpose To study the status of EGFR mutations and the expression of excision repair cross-complementation group 1 ( ER-CC1) and Ki-67 protein in patients with non-small cell lung cancer (NSCLC) and to examine the relationship between their expression and clinicopathologic features. Methods EGFR mutations were analyzed with DNA sequencing, and the expression of ERCC1 and Ki-67 protein was examined by immunohistochemistry EnVision. The relationship of EGFR mutations with the expression of ERCC1and Ki-67 and the clinicopathological features were analyzed. Results EGFR mutations were detected in 143 (143/291, 49. 1%) of the 291 specimens. EGFR mutations were found more frequently in women, non-smokers and adenocarcinoma. The difference of EGFR muta-tion rate between the histological subtypes according to the IASLC/ATS/ERS classification of lung adenocarcinoma was significantly ( P=0. 008). The mean tumor diameter was smaller in patients with EGFR mutations than in those with wild-type EGFR (P=0. 020). EGFR mutations were not related to age, lymph node metastasis. However, EGFR mutations were not related to the expression of ER-CC1 and Ki-67 protein (P>0. 050). Conclusions EGFR mutation is closely linked to several clinicopathological factors, such as gender, differentiation, and histological subtype. There is heterogeneity of EGFR mutation in patients with NSCLC. EGFR mutations were not related to the expression of ERCC1 and Ki-67 protein.

Relationship between cisplatin resistance of primary lung cancer and expression levels of ERCC1 and IGFBP5 in patient-derived tumor xenograft models / 中国肿瘤临床

Objective:To establish a lung cancer model of patient-derived tumor xenografts (PDTX) and to explore the relation-ship between primary cisplatin resistance and ERCC1 and IGFBP5 expression levels. Methods:Lung cancer tissues from 84 patients who underwent surgery were collected and implanted into nude mice. Patient characteristics for the first generation xenografts that were and were not engrafted were compared. Passage 3 xenografts were treated with cisplatin. The expression levels of ERCC1 and IGFBP5 in cisplatin-resistant and cisplatin-sensitive groups were detected using immunohistochemistry assay. Results:The model success rates were 32.14%(27/84) in first-generation xenografts, 88.89%(24/27) in second-generation xenografts, and 95.83%(23/24) in third-gener-ation xenografts. The tumorigenicity of first-generation xenografts was correlated with size, differentiation, clinical stage, and histologi-cal type. PDTX tumors maintain the histological type of parental tumors through serial passage in nude mice. ERCC1 expression level was significantly higher in the cisplatin-resistant group than in the cisplatin-sensitive group, whereas the IGFBP5 expression level was lower in the cisplatin-resistant group than in the cisplatin-sensitive group. Conclusion:Lung cancer PDTX models were successfully es-tablished, and histological characteristics of the primary cancers were retained. Therefore, the models may serve a function in preclini-cal research of lung tumor biology and for exploring the drug resistance mechanism of tumors. The cisplatin resistance of primary lung cancer may be correlated with the expression level of ERCC1 and IGFBP5 in lung carcinoma.