XPG is a novel biomarker of clinical outcome in advanced non-small-cell lung cancer

Variants of ERCC5 and the outcome of platinum-based regimens in non-small cell lung cancer: a prospective cohort study

Excision repair complementary complex 5 (ERCC5) is an important component in the repair pathway of platinum-induced damage. The current study evaluated the effect of ERCC5 variants (rs751402 and rs1047768) on the clinical outcome of platinum-based regimens in non-small cell lung cancer (NSCLC) patients. A prospective, cohort study was conducted on 57 newly diagnosed NSCLC Egyptian patients. Patients received either cisplatin or carboplatin-based chemotherapy. DNA was extracted and the variants were analyzed using real time PCR. This study found no significant difference between the studied variants and patients’ response to chemotherapy, progression-free survival (PFS) or overall survival (OS). However, a statistically significant association was found between the histologic subtypes and the studied variants (p = 0.028 and 0.018 for rs751402 and rs1047768, respectively). A statistically significant association was evident between the type of the allele present in the studied polymorphisms, p value = 0.000040. Moreover, the minor allele frequency (MAF) of the studied variants rs751402 and rs1047768 were similar to those of African and European populations, respectively. Results of this study have concluded that ERCC5 variants did not affect the clinical outcome of platinum-based chemotherapy in NSCLC. A significant coinheritance was found between the two variants of ERCC5. Moreover, the similarity between the MAF of the studied variants and the African or European population can guide future research when extrapolating data from African European populations to their Egyptian counterparts.

Effect of Sintilimab combined with Chemotherapy on Tumor Markers and Immune Function of advanced non-small cell lung cancer

Objective

To evaluate the effect of sintilimab combined with chemotherapy on tumor markers and immune function in advanced non-small cell lung cancer.

Methods

The study was conducted at Xi'an Medical University, China. The 120 patients with advanced NSCLC who were treated in our hospital from January 2016 to January 2020 were randomly divided into two groups, with 60 cases in each group. Patients in the control group received conventional GP chemotherapy, while those in the experimental group received intravenous injection of sindilimab on the basis of conventional GP chemotherapy. The changes of serum tumor markers CYFRA211, CEA, CA125 and T lymphocyte subsets CD3+, CD4+, CD8+, CD4+/CD8+ in the two groups prior to and after treatment were compared and analyzed. At the same time, the clinical efficacy at six months was compared between the two groups.

Results

The serum tumor markers CYFRA211, CEA and CA125 in the two groups after treatment were lower than those before treatment, and the difference was statistically significant (P=0.00). Specifically, the above-mentioned markers in the experimental group decreased more significantly than those in the control group, and the difference was statistically significant (CYFRA211, CA125, p=0.00; CEA, p=0.01; the levels of CD3+ and CD4+ in the experimental group were higher than those in the control group after treatment, with statistical significance (CD3+, p=0.00; CD4+, p=0.01)). No significant change can be seen in CD8+ (p=0.14), and the level of CD4+/CD8+ in the experimental group was higher than that in the control group, with a significant difference (p=0.02). The complete remission rate (CR) was 22% in the experimental group and 8% in the control group (P=0.04), which was statistically significant. The progress rate (PD) of the experimental group was significantly lower than that of the control group, with statistical significance (p=0.02). The overall response rate (RR) of the experimental group was more advantageous than that of the control group, with a statistically significant difference (p=0.01).

Conclusion

Compared with chemotherapy alone, significant therapeutic effects can be obtained in the treatment of advanced non-small cell lung cancer with sintilimab combined with chemotherapy. With this combination regimen, the level of serum tumor markers can be significantly reduced, the cellular immune function of patients can be improved, with the overall response rate of treatment increased, and the risk of progressive disease of patients reduced.

XPG is Modulated by miR-4715-3p and rs873601 Genotypes in Lung Cancer

Objective

XPG (Xeroderma pigmentosum group G, XPG), a single strand-specific DNA endonuclease in the nucleotide excision repair pathway, has been implicated in lung cancer. Potentially functional rs873601 in XPG is consistently associated with gastrointestinal cancer, and miR-4715-3p, targeting 3UTR of XPG, also influences the process of gastrointestinal carcinogenesis, however, the relationships between XPG and miR-4715-3p and rs873601 in lung cancer have not been elucidated.

Methods

A case-control study included 264 lung cancer patients and 264 cancer-free healthy controls and was designed to determine the relationships between rs873601 and lung cancer and the effect of miR-4715-3p on XPG expression in lung cancer. Fifty matched cases and controls were randomly selected from the lung cancer and control groups to assess the relationships between the expression levels of miR-4715-3p and XPG determined by using qRT-PCR. The association of rs873601 with lung cancer was analyzed by mass spectrometry, and function prediciton of rs873601 genotypes explored by web-based bioinformatics.

Results

miR-4715-3p in the lung cancer group was significantly increased compared with that in the control group (P = 0.011), upregulation of miR-4715-3p correlated with an increase in XPG mRNA (r = 0.399, P <0.05) in the lung cancer group. The AA genotype was associated with increased risk of lung cancer compared with the AG and GG genotypes of rs873601 (AG vs AA: OR = 0.231, 95% CI: 0.155–0.345, P <0.001 GG vs AA: OR = 0.300, 95% CI: 0.131–0.719, P = 0.003). The genetic association remained significant after adjustment for age, sex, smoking, and drinking, and rs873601-AA was associated with an increase in XPG mRNA in the lung cancer group. The results of web-based bioinformatics analysis indicated rs873601 genotypes might change XPG-RNA stability and bindability between XPG and miR-4715-3p.

Conclusion

Our data characterized that miR-4715-3p and rs873601 genotypes modified XPG expression in lung cancer. These findings may help to elucidate the mechanisms governing lung cancer.

An insight into clinical outcome of XPG polymorphisms in breast cancer

XPG polymorphisms are associated with varied clinical outcomes in different cancers but up-till now no study has been reported on breast cancer. Therefore, current study was aimed to explore the association of breast cancer risk factors and XPG polymorphisms (rs2296147 and rs1047768). It also investigated impact of XPG variants on overall survival and progression free survival among breast cancer cases. A total of 493 histopathologically identified breast cancer cases and 387 healthy females were genotyped by ARMS-PCR. Relationship between general characteristics, XPG polymorphisms and breast cancer risk was accessed by conditional logistic regression and illustrated by OR and 95% CI. Kaplan Meier test was applied to estimate survival distributions whereas log rank test demonstrated survival differences. Association of XPG variants with OS and PFS in breast cancer was illustrated by HR and 95% CI. Early onset of menopause, consanguinity and family history contributed (P < 0.05) towards breast cancer development. Both rs2296147 and rs1047768 SNPs were found to be associated (P < 0.05) with the risk of breast cancer. XPG rs1047768 was significantly associated with decreased PFS (HR 1.72; 95% CI 1.0-2.8) in breast cancer cases (P = 0.013) which was demonstrated by median time of 26 months for T > C variant when compared with median time of 37 months for TT genotype. No association was found between XPG rs2296147 polymorphism and survival analysis among breast cancer cases. XPG (rs1047768 T > C) variant may play a significant role in terms of decreased PFS and could be used as a predictor of unfavourable prognosis among breast cancer.

Single nucleotide polymorphisms of nucleotide excision repair pathway are significantly associated with outcomes of platinum-based chemotherapy in lung cancer

Nucleotide excision repair (NER) pathway plays critical roles in repairing DNA disorders caused by platinum. To comprehensively understand the association between variants of NER and clinical outcomes of platinum-based chemotherapy, 173 SNPs in 27 genes were selected to evaluate association with toxicities and efficiency in 1004 patients with advanced non-small cell lung cancer. The results showed that consecutive significant signals were observed in XPA, RPA1, POLD1, POLD3. Further subgroup analysis showed that GTF2H4 presented consecutive significant signals in clinical benefit among adenocarcimoma. In squamous cell carcinoma, rs4150558, rs2290280, rs8067195 were significantly associated with anemia, rs3786136 was significantly related to thrombocytopenia, ERCC5 presented consecutive significant signals in response rate. In patients receiving TP regimen, significant association presented in neutropenia, thrombocytopenia and gastrointestinal toxicity. Association with anemia and neutropenia were found in GP regimen. rs4150558 showed significant association with anemia in NP regimen. In patients > 58, ERCC5 showed consecutive significant signals in gastrointestinal toxicity. Survival analysis showed SNPs in POLD2, XPA, ERCC6 and POLE were significantly associated with progression free survival, SNPs in GTF2H4, ERCC6, GTF2HA, MAT1, POLD1 were significantly associated with overall survival. This study suggests SNPs in NER pathway could be potential predictors for clinical outcomes of platinum-based chemotherapy among NSCLC.

Genetic Polymorphisms and Platinum-based Chemotherapy Treatment Outcomes in Patients with Non-Small Cell Lung Cancer: A Genetic Epidemiology Study Based Meta-analysis

Data regarding genetic polymorphisms and platinum-based chemotherapy (PBC) treatment outcomes in patients with NSCLC are published at a growing pace, but the results are inconsistent. This meta-analysis integrated eligible candidate genes to better evaluate the pharmacogenetics of PBC in NSCLC patients. Relevant studies were retrieved from PubMed, Chinese National Knowledge Infrastructure and WANFANG databases. A total of 111 articles comprising 18,196 subjects were included for this study. The associations of genetic polymorphisms with treatment outcomes of PBC including overall response rate (ORR), overall survival (OS) and progression-free survival (PFS) were determined by analyzing the relative risk (RR), hazard ration (HR), corresponding 95% confidence interval (CI). Eleven polymorphisms in 9 genes, including ERCC1 rs11615 (OS), rs3212986 (ORR), XPA rs1800975 (ORR), XPD rs1052555 (OS, PFS), rs13181 (OS, PFS), XPG rs2296147 (OS), XRCC1 rs1799782 (ORR), XRCC3 rs861539 (ORR), GSTP1 rs1695 (ORR), MTHFR rs1801133 (ORR) and MDR1 rs1045642 (ORR), were found significantly associated with PBC treatment outcomes. These variants were mainly involved in DNA repair (EXCC1, XPA, XPD, XPG, XRCC1 and XRCC3), drug influx and efflux (MDR1), metabolism and detoxification (GSTP1) and DNA synthesis (MTHFR), and might be considered as potential prognostic biomarkers for assessing objective response and progression risk in NSCLC patients receiving platinum-based regimens.

Pharmacogenomics of platinum-based chemotherapy in non-small cell lung cancer: focusing on DNA repair systems

Drug therapy for non-small cell lung cancer consists mainly of platinum-based chemotherapy regimens. However, toxicity, drug resistance, and high risk of death have been seen in the clinic, which means there is a need for optimizing the use of medications. Platinum resistance could be mediated by a series of DNA repair pathways, and therefore, these pathways should be taken into account for optimizing drug using. The goal of pharmacogenomics is to elucidate genetic factors, such as DNA repair genes, which might underlie drug efficacy and effectiveness, and to improve therapeutic effects or guide personalized therapy as well. Here, we reviewed the current knowledge of pharmacogenomic data on DNA repair systems and examined whether they could be further translated into the clinic with evidence-based perspectives.

Predictive value of XPG rs2296147T>C polymorphism on clinical outcomes of cancer patients

The Xeroderma pigmentosum complementation group G (XPG) rs2296147T>C polymorphism is suspected to associate with the clinical outcomes of cancer patients. However, the results are inconsistent. This meta-analysis aimed to evaluate the reliable predictive value of XPG rs2296147T>C polymorphism on clinical outcomes of cancer patients. A total of 11 eligible studies were enrolled in this meta-analysis. Our results indicated that the cancer patients with TT and CT genotypes were significantly associated with better respond rates when compared with the CC genotype (TT versus (vs.) CC: odds ratio (OR) = 2.05, 95% confidence intervals (CIs), 1.32-3.20, P = 0.002; TT+CT vs. CC: OR= 1.57, 95% CI, 1.14-2.17, P = 0.005). The TT genotype and/or T allele might be associated with higher survival time for cancer patients than the CC genotype and/or C allele. The cumulative meta-analyses showed an apparent beneficial objective response of TT genotype on cancer patients. In conclusion, this meta-analysis suggests that the XPG rs2296147T>C polymorphism is associated with the clinical outcomes of cancer patients. The XPG rs2296147T>C polymorphism might be a predictive factor of prognosis in cancers patients and contribute to individual treatment in the future.

Genetic variants of DNA repair genes predict the survival of patients with esophageal squamous cell cancer receiving platinum-based adjuvant chemotherapy

Background

Adjuvant chemotherapy in patients with resected esophageal squamous cell cancer (ESCC) remains controversial for its uncertain role in improving overall survival (OS). Nucleotide excision repair (NER) removes DNA-adducts in tumor cells induced by the platinum-based chemotherapy and thus may modulate efficacy of the treatment. The present study evaluated if single nucleotide polymorphisms (SNPs) of NER genes were prognostic biomarkers in ESCC patients treated with platinum-based adjuvant chemotherapy (PAC).

Methods

The analysis included 572 patients, for whom six SNPs of NER genes [i.e., XPC (rs1870134 and rs2228001), ERCC2/XPD rs238406 and ERCC5/XPG (rs2094258, rs2296147 and rs873601)] were detected with the TaqMan assay. Kaplan–Meier analyses and Cox proportional hazards models were used to evaluate their associations with disease free survival (DFS) and OS of these ESCC patients receiving PAC. Receiving operating characteristic curve analysis was used to evaluate the role of the risk genotypes in the DFS and OS.

Results

We found that ERCC5/XPG rs2094258 and rs873601 and ERCC2/XPD rs238406 SNPs were independently associated with poorer DFS and OS of ESCC patients [ERCC5/XPG rs2094258: CT+TT vs. CC: adjusted hazards ratio (adjHR) = 1.68 and P = 0.012 for DFS; adjHR = 1.99 and P = 0.0001 for OS; ERCC5/XPG rs873601: GA+GG vs. AA: adjHR = 1.59 and P = 0.024 for DFS; adjHR = 1.91 and P = 0.0005 for OS; ERCC2/XPD rs238406: TT vs. GG+GT: adjHR = 1.43 and P = 0.020 for DFS; adjHR = 1.52 and P = 0.008 for OS]. These HRs increased as the number of risk genotypes increased in the combined analysis. The model combining the risk genotypes with clinical characteristics or the TNM stage system was better in predicting outcomes in ESCC patients with PAC.

Conclusion

SNPs of ERCC2/XPD and ERCC5/XPG may independently and jointly predict survival of ESCC patients treated with PAC in this study population. Further validation in other study populations is warranted.

Electronic supplementary material

The online version of this article (doi:10.1186/s12967-016-0903-z) contains supplementary material, which is available to authorized users.

XPG rs2296147 T>C polymorphism predicted clinical outcome in colorectal cancer

Xeroderma pigmentosum group G (XPG), one of key components of nucleotide excision repair pathway (NER), is involved in excision repair of UV-induced DNA damage. Single nucleotide polymorphisms (SNPs) in the XPG gene have been reported to associate with the clinical outcome of various cancer patients. We aimed to assess the impact of four potentially functional SNPs (rs2094258 C>T, rs2296147 T>C, rs751402 G>A, and rs873601 G>A) in the XPG gene on prognosis in colorectal cancer (CRC) patients. A total of 1901 patients diagnosed with pathologically confirmed CRC were genotyped for four XPG polymorphisms. Cox proportional hazards model analysis controlled for several confounding factors was conducted to compute hazard ratios (HRs) and 95% confidence intervals (CIs). Of the four included SNPs, only rs2296147 was shown to significantly affect progression-free survival (PFS) in CRC. Patients carrying rs2296147 CT/TT genotype had a significantly shorter median 10 years PFS than those carrying CC genotype (88.5 months vs. 118.1 months), and an increased progression risk were observed with rs2296147 (HR = 1.324, 95% CI = 1.046-1.667). Moreover, none of the four SNPs were associated with overall survival. In conclusion, our study showed that XPG rs2296147 CT/TT variants conferred significant survival disadvantage in CRC patients in term of PFS. XPG rs2296147 polymorphism could be predictive of unfavorable prognosis of CRC patients.

Correlation between expression of epidermal growth factor receptor and adverse reactions after chemotherapy of advanced non-small-cell lung cancer

OBJECTIVE

To analyze the correlation between expression of epidermal growth factor receptor (EGFR) and adverse reactions after chemotherapy of advanced non-small-cell lung cancer (NSCLC).

METHODS

A total of 120 NSCLC patients who were treated in our hospital from August 2009 to September 2011 were selected as an observation group, and another 120 healthy subjects were selected as a control group. EGFR expressions in both groups were detected. The observation group was subjected to combination chemotherapy, and their shorter- and long-term prognostic outcomes, adverse reactions and mortality were recorded. Meanwhile, correlation analysis was performed.

RESULTS

The observation group had significantly higher percentage and positive rate in EGFR expression than those of the control group (P<0.05). With increasing stage and lymphatic metastasis, the positive expression rate of EGFR rose significantly (P<0.05). In the observation group, the response rate of treatment was 62.5%, and the incidence rate of adverse reactions after chemotherapy was 28.3% (34/120). The 1-, 2- and 3-year survival rates were 38.3%, 15.0% and 10.0% respectively. Multiple Logistic regression analysis showed that TNM stage, lymphatic metastasis and positive EGFR expression were the main independent risk factors for post-chemotherapy adverse reactions (P<0.05).

CONCLUSION

Advanced NSCLC was commonly accompanied by high EGFR expression. Although chemotherapy was able to improve the prognosis and survival rate, adverse reactions were also induced, being associated with the pathological characteristics and EGFR expressions of patients.

Association study between XPG Asp1104His polymorphism and colorectal cancer risk in a Chinese population

Previous studies have reported that the Asp1104His polymorphism in Xeroderma Pigmentosum complementation group G (XPG) was associated with the susceptibility to colorectal cancer (CRC), although the results were inconsistent. This study was aim to investigate whether there existed an association between XPG Asp1104His polymorphism and CRC risk in the Chinese population, and a further meta-analysis was performed to consolidate the results. We found that XPG Asp1104His polymorphism was associated with a significantly increased CRC risk (dominant model: His/His + Asp/His vs. Asp/Asp, adjusted OR = 1.39, 95% CI = 1.14–1.69). Stratification analysis by clinical characteristics indicated that the His/His + Asp/His genotypes were associated with increased CRC susceptibility in patients with moderately differentiated grade, but not in poorly and well differentiated grade. Furthermore, a total of 5 eligible studies, including 2,649 CRC cases and 2,848 controls, were recruited for the meta-analysis. We identified that the meta-analysis reported a similar result in dominant model (OR = 1.35; 95% CI = 1.20–1.51). Especially, when stratified by ethnicity, an evidently increased risk was identified in the Asian population. In conclusion, our findings suggest that XPG Asp1104His polymorphism may increase the susceptibility of CRC, especially in Asian populations.

Genetic polymorphisms in XPG could predict clinical outcome of platinum-based chemotherapy for advanced non-small cell lung cancer

We conducted a prospective study to investigate the role of four single nucleotide polymorphisms (SNPs) of XPG on the clinical outcome of advanced non-small cell lung cancer (NSCLC) treated with platinum-based doublets chemotherapy. In total, 277 patients with histologically confirmed NSCLC were mainly from December 2007 and December 2008. The genotypes of rs2296147T>C, rs1047768C>T, rs873601G>A, and rs17655G>C were determined by polymerase chain reaction-restriction fragment length polymorphism. By univariate analysis, a shorter survival was associated with older age, sex, and higher disease stage. By multivariate Cox regression analysis, patients carrying rs2296147 TT genotype and T allele were prognostic factors of progression-free survival (PFS) and overall survival (OS). Similarly, patients carrying rs873601 GG genotype and G allele were marginally significantly associated with favorable outcome for PFS and OS. We found that individuals carrying both rs2296147 T allele and rs873601 G allele were associated with better PFS and OS. However, rs1047768C>T and rs17655G>C polymorphisms did not influence the PFS and OS of advanced NSCLC. In summary, our study provided statistical evidence that XPG rs2296147T>C and rs873601G>A polymorphisms may be used as surrogate markers toward individualizing NSCLC treatment strategies.