Impact of excision repair cross-complementing gene 1 (ERCC1) on the outcomes of patients with advanced gastric cancer: correlative study in Japan Clinical Oncology Group Trial JCOG9912

Present status and perspective of perioperative chemotherapy for patients with resectable pancreatic cancer in Japan

Adjuvant chemotherapy is the standard treatment for patients with resectable pancreatic ductal carcinoma. Perioperative chemotherapy has been given in less than 50% of patients with potentially resectable pancreatic cancer in Japan. A modified combination regimen of 5-fluorouracil, leucovorin, irinotecan, and oxaliplatin (mFOLFIRINOX; oxaliplatin 85 mg/m², leucovorin 400 mg/m², irinotecan 150 mg/m² on day 1, and 5-fluorouracil 2,400 mg/m² over 46 hours every 14 days for 12 cycles) is now preferred worldwide because it mitigates concerns regarding toxicity and tolerance. Adjuvant chemotherapeutic regimens employ S-1 in East Asia, whereas other areas use FOLFIRINOX, capecitabine plus gemcitabine, or gemcitabine monotherapy. Adjuvant chemoradiotherapy is not recommended because randomized controlled trials and meta-analyses revealed no survival benefit compared with chemotherapy. Preoperative chemotherapy with S-1 and gemcitabine combination chemotherapy for patients with resectable/borderline resectable pancreatic cancer significantly increased survival compared to upfront surgery in a recent clinical trial. Perioperative outcomes, including R0 resection rate and post-operative morbidity, were not significantly different between groups. When compared to upfront surgery, neoadjuvant S-1 and gemcitabine treatment significantly reduced the number of pathological nodal metastases in patients who underwent resection. Japanese guidelines therefore recommend neoadjuvant chemotherapy for patients with resectable pancreatic cancer. Preoperative chemotherapy can increase R0 cases by down-staging with higher relative dose intensity of chemotherapy. In contrast, patients who do not respond to chemotherapy may miss resection opportunities and would therefore be at a disadvantage. Therefore, it is critical for both patients and doctors that predictive markers for the response to chemotherapy are identified.

Novel Biomarkers of Gastric Adenocarcinoma: Current Research and Future Perspectives

Simple Summary

Gastric cancer is characterized by poor survival rates despite surgery and chemotherapy. Current research focuses on biomarkers to improve diagnosis and prognosis, and to enable targeted treatment strategies. The aim of our review was to give an overview over the wide range of novel biomarkers in gastric cancer. These biomarkers are targets of a specific treatment, such as antibodies against human epidermal growth factor receptor 2. Other promising biomarkers for targeted therapies that have shown relevance in clinical trials are vascular endothelial growth factor, programmed cell death protein 1, and Claudin 18.2. There is a vast number of biomarkers based on DNA, RNA, and protein expression, as well as detection of circulating tumor cells and the immune tumor microenvironment.

Abstract

Overall survival of gastric cancer remains low, as patients are often diagnosed with advanced stage disease. In this review, we give an overview of current research on biomarkers in gastric cancer and their implementation in treatment strategies. The HER2-targeting trastuzumab is the first molecular targeted agent approved for gastric cancer treatment. Other promising biomarkers for targeted therapies that have shown relevance in clinical trials are VEGF and Claudin 18.2. Expression of MET has been shown to be a negative prognostic factor in gastric cancer. Targeting the PD-1/PD-L1 pathway with immune checkpoint inhibitors has proven efficacy in advanced gastric cancer. Recent technology advances allow the detection of circulating tumor cells that may be used as diagnostic and prognostic indicators and for therapy monitoring in gastric cancer patients. Prognostic molecular subtypes of gastric cancer have been identified using genomic data. In addition, transcriptome profiling has allowed a comprehensive characterization of the immune and stromal microenvironment in gastric cancer and development of novel risk scores. These prognostic and predictive markers highlight the rapidly evolving field of research in gastric cancer, promising improved treatment stratification and identification of molecular targets for individualized treatment in gastric cancer.

A newly established monoclonal antibody against ERCC1 detects major isoforms of ERCC1 in gastric cancer

Identifying patients resistant to cisplatin treatment is expected to improve cisplatin-based chemotherapy for various types of cancers. Excision repair cross-complementing group 1 (ERCC1) is involved in several repair processes of cisplatin-induced DNA crosslinks. ERCC1 overexpression is reported as a candidate prognostic factor and considered to cause cisplatin resistance in major solid cancers. However, anti-ERCC1 antibodies capable of evaluating expression levels of ERCC1 in clinical specimens were not fully optimized. A mouse monoclonal antibody against human ERCC1 was generated in this study. The developed antibody 9D11 specifically detected isoforms of 201, 202, 203 but not 204, which lacks the exon 3 coding region. To evaluate the diagnostic usefulness of this antibody, we have focused on gastric cancer because it is one of the major cancers in Japan. When ERCC1 expression was analyzed in seventeen kinds of human gastric cancer cell lines, all the cell lines were found to express either 201, 202, and/or 203 as major isoforms of ERCC1, but not 204 by Western blotting analysis. Immunohistochemical staining showed that ERCC1 protein was exclusively detected in nuclei of the cells and a moderate level of constant positivity was observed in nuclei of vascular endothelial cells. It showed a clear staining pattern in clinical specimens of gastric cancers. Antibody 9D11 may thus be useful for estimating expression levels of ERCC1 in clinical specimens.

Molecular Bases of Mechanisms Accounting for Drug Resistance in Gastric Adenocarcinoma

Gastric adenocarcinoma (GAC) is the most common histological type of gastric cancer, the fifth according to the frequency and the third among the deadliest cancers. GAC high mortality is due to a combination of factors, such as silent evolution, late clinical presentation, underlying genetic heterogeneity, and effective mechanisms of chemoresistance (MOCs) that make the available antitumor drugs scarcely useful. MOCs include reduced drug uptake (MOC-1a), enhanced drug efflux (MOC-1b), low proportion of active agents in tumor cells due to impaired pro-drug activation or active drug inactivation (MOC-2), changes in molecular targets sensitive to anticancer drugs (MOC-3), enhanced ability of cancer cells to repair drug-induced DNA damage (MOC-4), decreased function of pro-apoptotic factors versus up-regulation of anti-apoptotic genes (MOC-5), changes in tumor cell microenvironment altering the response to anticancer agents (MOC-6), and phenotypic transformations, including epithelial-mesenchymal transition (EMT) and the appearance of stemness characteristics (MOC-7). This review summarizes updated information regarding the molecular bases accounting for these mechanisms and their impact on the lack of clinical response to the pharmacological treatment currently used in GAC. This knowledge is required to identify novel biomarkers to predict treatment failure and druggable targets, and to develop sensitizing strategies to overcome drug refractoriness in GAC.

Present status and perspective of chemotherapy for patients with unresectable advanced or metastatic gastric cancer in Japan

Patients with unresectable advanced or recurrent gastric cancer have a poor prognosis with overall survival times increasing by only a few months after anti-cancer drug therapy in the last four decades. The survival times from previous clinical trials for untreated metastatic gastric cancer in Japan are generally better than those reported from trials in European and North or South American countries. Therefore, the proportion of Japanese patients enrolled in recent global trials of novel anti-cancer drugs should be increased in order to identify drugs that specifically prolong the survival of such patients. S-1 plus oxaliplatin (SOX) therapy is the most commonly used standard first-line treatment for advanced gastric cancer in Japan. SOX induces mild nausea and vomiting, even in elderly patients, that can be treated by maintaining oral intake with adequate anti-emetic treatment usually given in an outpatient clinic. Neutropenia, nausea, and vomiting in SOX therapy were more frequently observed in female patients compared with males. Intensive toxic chemotherapy such as triplet therapy never prolonged overall survival or maintained a favorable quality of life. The current strategies used against metastatic gastric cancer need to be modified in regard to innovative treatments with current drugs, keeping in mind each categorized treatment population. In a real world of a diverse society even if the same treatment is performed, the outcome of the individual patient is different. It is important for each society to implement established treatment, knowing that the evidence from global trials aimed at drug approval does not necessarily show external validity.

Comparison of S-1-cisplatin every 5 weeks with capecitabine-cisplatin every 3 weeks for HER2-negative gastric cancer (recurrent after S-1 adjuvant therapy or chemotherapy-naïve advanced): pooled analysis of HERBIS-2 (OGSG 1103) and HERBIS-4A (OGSG 1105) trials

BACKGROUND

We previously reported the HERBIS-4A phase II trial comparing S-1 plus cisplatin (SP) with capecitabine plus cisplatin (XP) in chemotherapy-naïve patients with HER2-negative advanced gastric cancer (GC). We performed a pooled analysis of HERBIS-4A and HERBIS-2, the phase II trial comparing SP with XP in HER2-negative recurrent GC patients with a recurrence-free interval after S-1 adjuvant therapy of ≥ 6 months.

PATIENTS AND METHODS

Patients were randomly assigned to receive either SP [S-1 (40-60 mg twice daily for 21 days) plus cisplatin (60 mg/m² on day 8), every 5 weeks] or XP [capecitabine (1000 mg/m² twice daily for 14 days) plus cisplatin (80 mg/m² on day 1), every 3 weeks].

RESULTS

In the pooled analysis, SP (n = 44-50) showed a longer progression-free survival [6.4 versus 5.1 months; hazard ratio (HR), 0.666; P = 0.062], overall survival (14.8 versus 10.6 months; HR, 0.695; P = 0.099), and time to treatment failure (4.6 versus 3.6 months; HR, 0.668; P = 0.045) as well as a higher disease control rate (86.4% versus 68.1%, P = 0.149) compared with XP (n = 47-51). A significant survival advantage for SP over XP was apparent in patients with a performance status of 0, a differentiated-type tumor histology, or a primary tumor localization to the upper portion of the stomach.

CONCLUSION

Our pooled analysis supports the use of SP in the first-line setting for patients with HER2-negative advanced or recurrent GC with a recurrence-free interval of ≥ 6 months.

CLINICAL TRIAL REGISTRATION

The HERBIS-2 trial was registered with UMIN-CTR as UMIN000006105.

Update on gastric cancer treatments and gene therapies

Gastric cancer is an active topic of clinical and basic research due to high morbidity and mortality. To date, gastrectomy and chemotherapy are the only therapeutic options for gastric cancer patients, but drug resistance, either acquired or primary, is the main cause for treatment failure. Differences in development and response to cancer treatments have been observed among ethnically diverse GC patient populations. In spite of major incidence, GC Asian patients have a significantly better prognosis and response to treatments than Caucasian ones due to genetic discordances between the two populations. Gene therapy could be an alternative strategy to overcome such issues and especially CRISPR/Cas9 represents one of the most intriguing gene-editing system. Thus, in this review article, we want to provide an update on the currently used therapies for the treatment of advanced GC. Graphical abstract.

Comprehensive biomarker analyses identifies HER2, EGFR, MET RNA expression and thymidylate synthase 5'UTR SNP as predictors of benefit from S-1 adjuvant chemotherapy in Japanese patients with stage II/III gastric cancer

Purpose: A comprehensive molecular analysis was conducted to identify prognostic and predictive markers for adjuvant S-1 chemotherapy in stage II/III Japanese gastric cancer (GC) patients and to evaluate their potential suitability for alternative cytotoxic or targeted drugs.

Experimental Design: We investigated genetic polymorphisms of enzymes potentially involved in 5-fluoruracil (5-FU) metabolism as well as platinum resistance, previously identified genomic subtypes potentially predicting 5-FU benefit, and mRNA expression levels of receptor tyrosine kinases and KRAS as potential treatment targets in a single institution cohort of 252 stage II/III GC patients treated with or without S-1 after D2 gastrectomy.

Results: 88% and 62% GC had a potentially 5-FU sensitive phenotype by SNP analyses of TS 3'UTR, and TS 5'UTR, respectively. 24%, 46%, 40%, 5%, and 44% GC had a potentially platinum sensitive phenotype by SNP analyses of GSTP1, ERCC1 rs11615, ERCC1 rs3212986, ERCC2, and XRCC1, respectively. High HER2, EGFR, FGFR2, or MET mRNA expression was observed in 49%, 66%, 72%, and 54% GC, respectively. High HER2 expression was the only significant prognosticator (HR=3.912, 95%CI: 1.706-8.973, p=0.0005). High HER2 (p=0.031), low EGFR (p=0.124), high MET (p=0.165) RNA expression, and TS 5'UTR subtype 2R/2R, 2R/3C, or 3C (p=0.058) were significant independent predictors for S-1 resistance.

Conclusions: The present study suggests that platinum-based or RTK targeted agents could be alternative treatment options for a substantial subgroup of Japanese GC patients currently treated with S-1. HER2, EGFR, MET, and TS 5'UTR SNP appear to be promising predictive markers for S-1 resistance warranting validation in an independent GC series.

The use of DNA repair genes as prognostic indicators of gastric cancer

DNA repair genes can be used as prognostic biomarkers in many types of cancer. We aimed to identify prognostic DNA repair genes in patients with gastric cancer (GC) by systematically bioinformatic approaches using web-based database. Global gene expression profiles from altogether 1,325 GC patients' samples from six independent datasets were included in the study. Clustering analysis was performed to screen potentially abnormal DNA repair genes related to the prognosis of GC, followed by unsupervised clustering analysis to identify molecular subtypes of GC. Characteristics and prognosis differences were analyzed among these molecular subtypes, and modular key genes in molecular subtypes were identified based on changes in expression correlation. Multivariate Cox proportional hazard analysis was used to find the independent prognostic gene. Kaplan-Meier method and log-rank test was used to estimate correlations of key DNA repair genes with GC patients'overall survival. There were 57 key genes significantly associated to GC patients' prognosis, and patients were stratified into three molecular clusters based on their expression profiles, in which patients in Cluster 3 showed the best survival (P < 0.05). After a three-phase training, test and validation process, the expression profile of 13 independent key DNA repair genes were identified can classify the prognostic risk of patients. Compared with patients with low-risk score, patients with high risk score in the training set had shorter overall survival (P < 0.0001). Furthermore, we verified equivalent findings by these key DNA repair genes in the test set (P < 0.0001) and the independent validation set (P = 0.0024). Our results suggest a great potential for the use of DNA repair gene profiling as a powerful marker in prognostication and inform treatment decisions for GC patients.

Bioinformatic exploration of OLFML2B overexpression in gastric cancer base on multiple analyzing tools

Background

Gastric cancer (GC) is one of the most commonly occuring gastrointestinal tumor types, and early diagnosis and operation have a notable effect on the prognosis of patients. Although certain markers, including HER2, VEGER-2, ERCC1 and Bcl-2, have been utilized in clinical practise to screen out new patients with GC, the results of using these markers remains poor. The role of olfactomedin-like 2B (OLFML2B) in GC, as a member of the olfactomedin domain-containing proteins family, is remain unclear.

Methods

In the present study, we assessed the expression of OLFML2B, including mRNA and protein level, by using The Cancer Genome Atlas (TCGA) database and 13 pairs of clinical samples between GC and NG tissues. The correlation between expression of OLFML2B and prognosis of GC was evaculated by the Kaplan-Meier plotter and OncoLnc online tools. In addition, mechanism analysis of OLFML2B in GC was explored thought bioinformatic tools, including cBioPortal and FunRich software.

Results

In our study, the mRNA expression of OLFML2B in GC both TCGA database and clinical samples was consistently revealed to be significantly higher compared with that in NG tissues (P < 0.0001 for TCGA database and P = 0.0034 for clinical samples), and high OLFML2B expression was found in 9 (69.23%) of 13 clinical GC by immunohistochemistry and was positively correlated with the depth of tumor invasion and clinical stage (TNM). In addition, the AUC for a ROC of 0.867 indicated a moderate diagnostic ability of OLFML2B for GC. Survival analysis from the Kaplan-Meier plotter (P = 2.6 × 10^− 6) and OncoLnc (P = 0.00276) revealed that the high expression of OLFML2B was associated with a short overall survival. Futhermore, 5% (24/478) alterations of OLFML2B were identified from cBioPortal, and among them, missense mutation (14/478) was the primary type. The results from FunRich revealed that OLFML2B participated in mediating multiple biological processes including cell growth and maintenance, regulation of the cell cycle, apoptosis and cell communication through multiple signaling pathways including the M/G1 transition pathway, post-translational protein modification and DNA replication pre-initiation.

Conclusions

Taken together, it could be deduced that OLFML2B may act as an oncogene in the development of GC and the overexpression of OLFML2B in GC may be used as a novel diagnostic and prognostic target for GC.

Prognostic Value of Excision Repair Cross-Complementing mRNA Expression in Gastric Cancer

Except for excision repair cross-complementing 1 (ERCC1), mRNA expression of the remaining ERCC genes has not been investigated in the prognosis of gastric cancer (GC). The present study aimed to explore the mRNA expression and prognostic values of each member of the ERCC family in GC patients by using the Kaplan–Meier (KM) plotter tool. The details of each ERCC family member were entered into a database and GC patients were separated into high and low expression to draw survival plots using the KM plotter. In the present study, we observed that high expression of ERCC1 mRNA was significantly associated with longer overall survival (OS) for all GC patients (hazard ratio [HR]=0.77, 95% confidence intervals [CI]=0.63–0.95, P=0.016) compared with low expression. High expression of ERCC4 and ERCC6 mRNA indicated a worse OS for all GC patients (HR=1.28, 95% CI=1.02–1.6, P=0.035 and HR=1.25, 95% CI=1.02–1.54, P=0.029, respectively) and especially for patients with intestinal-type GC (HR=1.87, 95% CI=1.26–2.79, P=0.0018 and HR=1.62, 95% CI=1.04–2.54, P=0.033, respectively). High ERCC8 mRNA expression indicated a worse OS for all GC patients (HR=1.34, 95% CI=1.02–1.76, P=0.034) and especially for patients with diffuse-type GC (HR=2.25, 95% CI=1.36–3.75, P=0.0013). In conclusion, our findings indicate that ERCC4, ERCC6, and ERCC8 may be potential biomarkers for GC prognosis and may serve as potential therapeutic targets for GC. However, these findings still need further verification.

Examination of the expression and prognostic significance of DLGAPs in gastric cancer using the TCGA database and bioinformatic analysis

The discs large-associated protein (DLGAP) family has been implicated in psychological and neurological diseases. However, few studies have explored the association between the expression of DLGAPs and different types of cancer. Therefore, the present study analyzed the status of DLGAPs in gastric cancer (GC) using bioinformatic tools. Analyses of data obtained from The Cancer Genome Atlas and Gene Expression Omnibus databases revealed that there was selective upregulation of DLGAP4 and DLGAP5 expression in GC tissues when compared with normal gastric tissues. In addition, survival analysis using OncoLnc indicated that high expression of DLGAP4 was significantly correlated with shorter overall survival for all GC patients. However, Kaplan-Meier plots demonstrated that the expression of all DLGAPs, except for DLGAP3, was correlated with patient prognosis; DLGAP4 was consistently associated with GC. DLGAP4 mRNA and protein distributions were examined by reverse transcription-quantitative polymerase chain reaction and immunohistochemsitry. Furthermore, its mutation rate and associated biological processes and signaling pathways were assessed in GC with cBioPortal and FunRich analyses. Taken together, these results indicated that DLGAP4 may serve an oncogenic role in GC development and may be a monitoring target for GC prognosis.

Prognostic and predictive factors for overall survival in metastatic oesophagogastric cancer: A systematic review and meta-analysis

BACKGROUND

Consistent evidence on prognostic and predictive factors for advanced oesophagogastric cancer is lacking. Therefore, we performed a systematic review and meta-analysis.

METHODS

We searched PubMed, Embase and the Cochrane Central Register of Controlled Trials (CENTRAL) databases for phase II/III randomised controlled trials (RCTs) until February 2017 on palliative systemic therapy for advanced oesophagogastric cancer that reported prognostic or predictive factors for overall survival (PROSPERO-CRD42014015177). Prognostic factors were identified from multivariate regression analyses in study reports. Factors were considered potentially clinically relevant if statistically significant (P ≤ 0.05) in multivariate analysis in ≥50% of the total number of patients in the pooled sample of the RCTs and were reported with a pooled sample size of ≥600 patients in the first-line or ≥300 patients in the beyond first-line setting. Predictive factors were identified from time-to-event stratified treatment comparisons and deemed potentially clinically relevant if the P-value for interaction between subgroups was ≤0.20 and the hazard ratio in one of the subgroups was significant (P ≤ 0.05).

RESULTS

Forty-six original RCTs were included (n = 15,392 patients) reporting on first-line (n = 33) and beyond first-line therapy (n = 13). Seventeen prognostic factors for overall survival in the first-line and four in the beyond first-line treatment setting were potentially clinically relevant. Twenty-one predictive factors in first-line and nine in beyond first-line treatment setting were potentially relevant regarding treatment efficacy.

CONCLUSIONS

The prognostic and predictive factors identified in this systematic review can be used to characterise patients in clinical practice, be included in future trial designs, enrich prognostic tools and generate hypotheses to be tested in future research to promote patient-centred treatment.

Relationship Between Expression of Proteins ERCC1, ERCC2, and XRCC1 and Clinical Outcomes in Patients with Rectal Cancer Treated with FOLFOX-Based Preoperative Chemoradiotherapy

BACKGROUND

Platinum resistance enhances DNA damage repair through nucleotide excision repair mechanisms involving the excision repair cross-complementing group 1 (ERCC1), X-ray cross-complementing group 1 (XRCC1), and excision repair cross-complementing group 2 (ERCC2). We evaluated the correlation between the expression of these three DNA repair genes and clinical outcomes in patients with rectal cancer receiving FOLFOX-based preoperative chemoradiotherapy (CRT).

METHODS

Using immunohistochemistry, we examined the expression of ERCC1, ERCC2, and XRCC1 in pre-CRT cancer tissues from 86 patients with rectal cancer who had undergone curative resection and preoperative CRT with FOLFOX-4 to identify potential predictors of clinical outcomes.

RESULTS

Following CRT, 57 and 29 patients were classified as responders (pathological tumor regression grade TRG 0 and TRG 1) and poor responders (TRG 2 and TRG 3), respectively. The multivariate analysis revealed that ERCC1 overexpression was correlated with a poor CRT response [p < 0.0001; odds ratio (OR), 9.397; 95% confidence interval (CI) 2.721-32.457]. Furthermore, a poor response to CRT (pathological TRG of 2-3) (p = 0.18; OR 5.685; 95% CI 1.349-23.954) and abnormal pre-CRT serum carcinoembryonic antigen levels (>5 ng/mL) (p = 0.03; OR 6.288; 95% CI 1.198-33.006) were independent predictors of postoperative relapse. By contrast, ERCC2 and XRCC1 expression did not play predictive roles in the analyzed patients.

CONCLUSIONS

ERCC1 overexpression is associated with a poor preoperative CRT response in patients with rectal cancer receiving FOLFOX-based preoperative CRT. ERCC1 is a potential biomarker for identifying patients who can benefit from customized treatment programs.

ERCC1 rs3212986 A/C polymorphism is not associated with chemotherapy treatment outcomes in gastric cancer patients: evidence from 11 publications in Chinese populations

BACKGROUND

A number of studies have investigated the roles of excision repair cross-complementation group 1 (ERCC1) gene rs3212986 polymorphisms as potential biomarkers in gastric cancer (GC). However, the results were inconsistent. Here, we performed a meta-analysis to explore ERCC1 rs3212986 polymorphisms in the chemotherapy response and clinical outcome of GC.

METHODS

PubMed, Embase, and Web of Science were searched up to July 28, 2017, for studies on the association between ERCC1 rs3212986 A/C polymorphisms and response to chemotherapy as well as overall survival time of GC. A fixed-effect or random-effect model was used to calculate the pooled odds ratios (ORs) based on the results from the heterogeneity tests.

RESULTS

The result revealed that there was no significant association between the ERCC1 rs3212986 A/C polymorphism and response to chemotherapy in GC under comparison models (AA + CA versus CC, OR 0.95, P=0.80, AA versus CA, OR 0.85, P=0.55, AA versus CC, OR 0.74, P=0.47). Further identification suggested that ERCC1 rs3212986 A/C polymorphisms were not linked with the overall survival of GC (AA + CA versus CC, OR 1.09, P=0.52, AA versus CA, OR 1.05, P=0.85, AA versus CC, OR 1.43, P=0.23).

CONCLUSION

Our meta-analysis indicated that the ERCC1 rs3212986 A/C polymorphism was not associated with response to chemotherapy or overall survival time in GC. Well-designed studies with larger sample sizes and more ethnic groups should be performed to further validate our results.

Expression of the cytoskeleton regulatory protein Mena in human gastric carcinoma and its prognostic significance

The cytoskeleton regulatory protein Mena is reportedly overexpressed in breast cancer; however, data regarding its expression level and clinical significance in gastric carcinoma (GC) is limited. The aim of the present study was to investigate Mena expression levels and prognostic significance in GC. Mena mRNA expression level was determined by reverse transcription-quantitative polymerase chain reaction in 10 paired GC and adjacent normal tissues. The Mena protein expression level was analyzed in paraffin-embedded GC samples and adjacent normal tissues by immunohistochemistry. Statistical analyses were also performed to evaluate the clinicopathological significance of Mena. The results revealed that the mRNA expression level of Mena was significantly higher in G Ct issues compared with in adjacent normal tissues from10 paired samples. In the paraffin-embedded tissue samples, the protein expression level of Mena was higher in G Ct issues compared with in adjacent normal tissues. Compared with adjacent normal tissues, Mena overexpression was observed in 52.83% (56/106) of patients. The overexpression of Mena was significantly associated with the T stage (P=0.033), tumor-node-metastasis (TNM) stage (P<0.001) and decreased overall survival (P<0.001). Based on a multivariate analysis, Mena expression level was an independent prognostic factor for overall survival time. In conclusion, Mena wasoverexpressed in G C tissues and significantly associated with the T stage, TNM stage and overall survival time. Mena may therefore be suitable as a prognostic indicator for patients with GC.

Functional genetic variants of XRCC4 and ERCC1 predict survival of gastric cancer patients treated with chemotherapy by regulating the gene expression

DNA repair protects genomic integrity and may modulate chemotherapy efficacy. Few large-scale studies have evaluated predictive roles of genetic variants of DNA repair genes in survival of Chinese gastric cancer (GCa) patients treated with chemotherapy. Here, we assessed the roles of 35 single nucleotide polymorphisms (SNPs) in DNA repair genes in survival of 1002 GCa patients, of whom 694 received chemotherapy and 308 did not. Among patients receiving chemotherapy, the ERCC1 rs2298881A allele was associated with a better survival [hazards ratio (HR) = 0.82, 95% confidence interval (CI) = 0.69-0.98; P = 0.03], whereas two XRCC4 SNPs were associated with a worse survival (HR = 1.26, 95% CI = 1.03-1.54 for the rs10040363G allele, P = 0.02; and HR = 1.30, 95% CI = 1.06-1.59 for the rs2075685T allele, P = 0.01). These three SNPs were unique survival predictors for patients treated with chemotherapy (P < 0.05 for all) but not for patients without chemotherapy (P > 0.05 for all), suggesting that they modulated chemotherapy efficacy. Patients who received chemotherapy and had haplotypes with at least one death-risk allele in XRCC4 had a poor survival, and the trend for an increase in the number of death-risk alleles adversely affecting the survival was also observed in an allelic dose-dependent manner (P_trend  = 0.001). Further functional analysis revealed that the death-risk alleles up-regulated the gene expression, leading to a worse survival as suggested by our meta-analysis pooling both mRNA microarray data from the GEO database and published data (ERCC1: HR = 1.31 [1.08-1.58]; P = 0.006). These functional genetic variants may independently or jointly affect survival in chemotherapy-treated GCa patients by modulating the gene expression in the tumors.

Increased ERCC1 expression is linked to chromosomal aberrations and adverse tumor biology in prostate cancer

BACKGROUND

Animal model experiments have suggested a role of the DNA repair protein ERCC1 (Excision Repair Cross-Complementation Group 1) in prostate cancer progression.

METHODS

To better understand the impact of ERCC1 protein expression in human prostate cancer, a preexisting tissue microarray (TMA) containing more than 12,000 prostate cancer specimens was analyzed by immunohistochemistry and data were compared with tumor phenotype, PSA recurrence and several of the most common genomic alterations (TMPRSS2:ERG fusions: deletions of PTEN, 6q, 5q, 3p).

RESULTS

ERCC1 staining was seen in 64.7% of 10,436 interpretable tissues and was considered weak in 37.1%, moderate in 22.6% and strong in 5% of tumors. High-level ERCC1 staining was linked to advanced pT stage, high Gleason grade, positive lymph nodes, high pre-operative serum PSA, and positive surgical margin status (p < 0.0001 each). High ERCC1 expression was strongly associated with an elevated risk of PSA recurrence (p < 0.0001). This was independent of established prognostic features. A subgroup analysis of cancers defined by comparable quantitative Gleason grades revealed that the prognostic impact was mostly driven by low-grade tumors with a Gleason 3 + 3 or 3 + 4 (Gleason 4: ≤5%). High ERCC1 expression was strongly associated with the presence of genomic alterations and expression levels increased with the number of deletions present in the tumor. These latter data suggest a functional relationship of ERCC1 expression with genomic instability.

CONCLUSION

The results of our study demonstrate that expression of ERCC1 - a potential surrogate for genomic instability - is an independent prognostic marker in prostate cancer with particular importance in low-grade tumors.

A phase II study of preoperative chemotherapy with docetaxel, cisplatin, and S-1 followed by gastrectomy with D2 plus para-aortic lymph node dissection for gastric cancer with extensive lymph node metastasis: JCOG1002

BACKGROUND

Gastric cancer with extensive lymph node metastasis is commonly considered unresectable, with a poor prognosis. We previously reported the results of the use of cisplatin and S-1 as preoperative chemotherapy for gastric cancer with extensive lymph node metastasis; docetaxel, cisplatin, and S-1 (DCS) have now been investigated for the same purpose.

METHODS

Patients received two or three 28-day cycles of DCS therapy (docetaxel at 40 mg/m² and cisplatin at 60 mg/m² on day 1, S-1 at 40 mg/m² twice daily for 2 weeks) followed by gastrectomy with D2 plus para-aortic nodal dissection. After R0 resection, S-1 chemotherapy was given for 1 year. The primary end point was the response rate (RR) to preoperative chemotherapy determined by central peer review according to the Response Evaluation Criteria in Solid Tumors version 1.0. The planned sample size was 50, with one-sided alpha of 10 %, power of 80 %, expected RR of 80 %, and threshold of 65 %.

RESULTS

Between July 2011 and May 2013, 53 patients were enrolled, of whom 52 were eligible. The clinical RR was 57.7 % [30/52, 80 % confidence interval 47.9-67.1 %, p = 0.89], and R0 resection was achieved in 84.6 % of patients (44/52). Common grade 3 or grade 4 adverse events during DCS therapy were leukocytopenia (18.9 %), neutropenia (39.6 %), and hyponatremia (15.1 %). The common grade 3 or grade 4 surgical morbidity was abdominal infection (10.2 %). The pathological RR was 50.0 % (26/52).

CONCLUSIONS

Preoperative DCS therapy was feasible but did not show a sufficient RR. Preoperative cisplatin and S-1 therapy is still considered the tentative standard treatment for this population until survival results are known.

Chemosensitizing effect of shRNA-mediated ERCC1 silencing on a Xuanwei lung adenocarcinoma cell line and its clinical significance

Lung cancer is a common fatal malignancy in both men and women. Xuanwei, Yunnan has the highest incidence of lung cancer in China. The area has a specific risk factor in the domestic combustion of bituminous coal, and lung cancer patients from this area tend to be resistant to platinum-based treatments. However, little is known about the mechanism of platinum resistance in patients from Xuanwei. Herein, we used lentiviral infection with shRNA to silence expression of the DNA repair enzyme ERCC1 in XWLC05 both in its RNA and protein expression level, a lung adenoma cell line derived from a patient from Xuanwei. ERCC1 expression in this cell line is high and contributes to its resistance to cisplatin. Suppression of ERCC1 decreased XWLC05 proliferation in vitro (IC50 of cisplatin 1.34 µM for shRNA-infected cells vs. 4.54 µM for control cells) and increased the apoptotic rate after treatment with cisplatin (81.2% shRNA cells vs. 58% control cells, P<0.05). Progression-free survival was longer in ERCC1-negative lung adenoma patients than those with high ERCC1 levels (30 vs. 11 months, P<0.0001). ERCC1 expression was identified as a prognostic marker for overall survival in the patient cohort with operable lesions. Taken together, our data identify ERCC1 as a disease marker in lung adenoma patients from Xuanwei and confirm the significance of resection for the subsequent effect of platinum treatment in these patients. Additional studies are needed to determine the mechanism of ERCC1-induced platinum resistance in lung adenoma patients from Xuanwei.

The Impact of the Expression Level of Intratumoral Dihydropyrimidine Dehydrogenase on Chemotherapy Sensitivity and Survival of Patients in Gastric Cancer: A Meta-Analysis

The potential impact that the intratumoral expression level of dihydropyrimidine dehydrogenase (DPD) has on chemotherapy sensitivity and long-term survival for gastric cancer (GC) patients remains controversial; therefore, this study seeks to clarify this issue. Our meta-analysis was performed using Review Manager (RevMan) 5.3 software. In vitro drug sensitivity tests, correlation coefficients between sensitivity to 5-fluorouracil (5-FU), and expression levels of intratumoral DPD were used as effective indexes to analyse. Overall survival (OS) and progression-free survival (PFS) were used as endpoints for patient outcome, and hazard ratios (HRs) and 95% confidence intervals (CIs) were noted as measures of effect. There were 15 eligible studies including 1805 patients for the final analysis. The analysis revealed a statistically significant difference between the expression level of intratumoral DPD activity, DPD mRNA levels, and sensitivity to 5-FU in GC patients, with high expression levels of intratumoral DPD resulting in low sensitivity to 5-FU. However, no matter what therapeutic regimens were used, there was no significant difference for patient outcomes between high and low DPD expression groups, either in OS or in PFS. In conclusion, high levels of intratumoral DPD expression have a negative impact on sensitivity to 5-FU in GC patients, but no prognostic value for long-term survival was uncovered.

Predictive biomarkers for targeted and cytotoxic agents in gastric cancer for personalized medicine

Gastric cancer (GC) is the fourth most common cancer and the second leading cause of cancer. The treatment of GC remains challenging as the outcomes achieved with surgery alone or adjuvant or neoadjuvant chemotherapy and radiotherapy are relatively poor. New treatment strategies are emerging and are being tested in solid tumors including GC. Over the past few years, the treatment of metastatic colorectal cancer (CRC) has made great advances, but strategies to manage GC have improved little. Multiple drug resistance is common in GC chemotherapy and targeted therapy; some patients appear to receive treatment that is suboptimal or even inefficacious. Unfortunately, there are few validated predictive biomarkers to guide the tailored treatment of GC. ToGA and AVAGAST are two phase III trials that tested the efficacy and safety of targeted agents in advanced gastric cancer (AGC), and results clearly indicated that patients need to be selected and that targeted agents are the best hope for better results. This review aims to provide an overview of potential predictive biomarkers for cytotoxic and targeted agents in GC.

Roles of XRCC1/XPD/ERCC1 Polymorphisms in Predicting Prognosis of Hepatocellular Carcinoma in Patients Receiving Transcatheter Arterial Chemoembolization

OBJECTIVE

To investigate the potential prognostic roles of polymorphisms in the X-ray repair cross-complementing group 1 (XPCC1), xeroderma pigmentosum group D (XPD) and excision repair cross-complementing group 1 (ERCC1) genes for patients with hepatocellular carcinoma (HCC) receiving transcatheter arterial chemoembolization (TACE).

METHODS

Clinical data and blood samples from 308 HCC patients receiving TACE were collected between January 2010 and December 2013. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RLFP) analyses was used to determine the genotypes of the XPCC1 (rs25487), XPD (rs13181) and ERCC1 (rs11615) genes. The relationships between the genotypes and the efficacy of TACE treatment were analyzed.

RESULTS

The XRCCI rs25487 polymorphism was associated with a favorable prognosis in HCC patients receiving TACE (p = 0.006), and patients carrying variant genotypes (A/A + G/A) were associated with significantly reduced risk of death compared with those with the wild genotype (G/G) (HR = 0.556; 95% CI = 0.354-0.874). These findings were supported by Kaplan-Meier survival curve analysis showing that median survival time for patients with A/A + G/A genotypes was significantly longer compared with those with the G/G genotype (11.2 month vs. 8.0 months; log rank p = 0.006). Stratified analyses revealed that A/A + G/A genotypes of XRCC1 rs25487 are associated with significantly reduced risk of death compared with the G/G genotype in patients grouped by tumor size, portal vein tumor thrombus (PVTT), alpha-fetoprotein (AFP) and TNM stage (all p < 0.05). The ERCC1 rs13181 and XPD rs11615 polymorphisms were not predictive of clinical outcome for HCC patients receiving TACE (both p > 0.05).

CONCLUSION

The XRCC1 rs25487 polymorphisms are prognostic for HCC patients receiving TACE. The ERCC1 and XPD polymorphisms had no relationship to the clinical outcomes.

Advancing pharmacological treatment options for advanced gastric cancer

INTRODUCTION

Gastric cancer is the third most common cause of cancer-related deaths worldwide. Improvement of conventional chemotherapy has been modest in the past decades.

AREAS COVERED

We review recent important studies of metastatic or recurrent gastric cancer. For human epidermal growth factor receptors 2 (HER2) negative cancer, standard treatments are combinations of fluoropyrimidine and platinum with or without epirubicin or docetaxel in first-line therapy. Controversy exists regarding the use of triplet chemotherapies due to their toxicity. For HER2 positive cancer, standard treatments are combinations of fluoropyrimidine and cisplatin with trastuzumab. As second- or third-line treatment, taxanes or irinotecan prolonged survival compared with best supportive care alone, but the extension of overall survival was only 1 - 2 months. A recent study demonstrated that ramucirumab plus paclitaxel improved survival as a second-line therapy.

EXPERT OPINION

Most trials have failed to demonstrate a benefit of targeted agents. It is important to identify predictive biomarkers to enrich an appropriate patient population for targeted agents such as HER2 status for trastuzumab.

PRR11 Is a Prognostic Marker and Potential Oncogene in Patients with Gastric Cancer

PRR11 is a potential candidate oncogene that has been implicated in the pathogenesis of lung cancer, however the role of PRR11 in gastric cancer is currently unclear. In the present study, we investigated the role of PRR11 in gastric cancer by evaluating its expression status in samples from a cohort of 216 patients with gastric cancer. PRR11 was found to be overexpressed in 107 (49.5%) patients by immunohistochemistry of tissue microarrays generated using the patient samples. Furthermore, PRR11 overexpression was found to correlate significantly with clinicopathologic features such as tumor invasion, tumor differentiation, and disease stage. Survival analysis of the cohort revealed that PRR11 is an independent prognostic factor for gastric cancer patients. PRR11 was stably silenced in a gastric carcinoma cell line using an shRNA-based approach, and treated cells showed decreased cellular proliferation and colony formation in vitro and cell growth in vivo, companied by decreased expression of CTHRC1 and increased expression of LXN, proteins involved in tumor progression. Evaluation of human gastric cancer samples demonstrated that PRR11 expression was also associated with increased CTHRC1 and decreased LXN expression. These data indicate that PRR11 may be widely activated in human gastric cancer and are consistent with the hypothesis that PRR11 functions as an oncogene in the development and progression of gastric cancer.

Prognostic value of excision repair cross-complementation group 1 expression in gastric cancer: A meta-analysis

The prognostic impact of excision repair cross-complementation group 1 (ERCC1) expression in gastric cancer (GC) has been investigated for decades, but has yielded controversial results. The aim of the present study was to provide a precise evaluation of whether the expression levels of ERCC1 are associated with overall survival (OS) in patients with GC. A systematic search of Medline and Embase was conducted. Original studies concerning OS and ERCC1 expression were included for critical appraisal. A total of 15 studies comprising 1,425 patients with GC were identified. The results revealed that high/positive ERCC1 expression was an indicator of poor survival in patients with GC [hazard ratio (HR) 1.48; 95% confidence interval (CI) 1.02–2.10; P=0.036; I²=83.8%; random-effects model] compared with low/negative ERCC1 expression. Subgroup analysis indicated that high/positive ERCC1 expression had a significant unfavorable impact on OS in the group of patients evaluated by reverse transcription polymerase chain reaction (RT-PCR; HR 2.57; 95% CI 1.49–4.45). Furthermore, high/positive ERCC1 expression was found to be associated with poor survival in patients receiving platinum-based chemotherapy in the RT-PCR group (HR 2.13; 95% CI 1.06–4.27). These data suggest that ERCC1 may be a useful prognostic factor for GC. In addition, low mRNA levels of ERCC1 appear to be associated with a significant favorable OS benefit from platinum-based chemotherapy.

How prognostic and predictive biomarkers are transforming our understanding and management of advanced gastric cancer

BACKGROUND

Gastric cancer (GC) is the second leading cause of cancer death worldwide. GC is a heterogeneous disease in terms of histology, anatomy, and epidemiology. There is also wide variability in how GC is treated in both the resectable and unresectable settings. Identification of prognostic and predictive biomarkers is critical to help direct and tailor therapy for this deadly disease.

METHODS

A literature search was done using Medline and MeSH terms for GC and predictive biomarkers and prognostic biomarkers. The search was limited to human subjects and the English language. There was no limit on dates. Published data and unpublished abstracts with clinical relevance were included.

RESULTS

Many potential prognostic and predictive biomarkers have been assessed for GC, some of which are becoming practice changing. This review is focused on clinically relevant biomarkers, including EGFR, HER2, various markers of angiogenesis, proto-oncogene MET, and the mammalian target of rapamycin.

CONCLUSION

GC is a deadly and heterogeneous disease for which biomarkers are beginning to change our understanding of prognosis and management. The recognition of predictive biomarkers, such as HER2 and vascular endothelial growth factor, has been an exciting development in the management of GC, validating the use of targeted drugs trastuzumab and ramucirumab. MET is another potential predictive marker that may be targeted in GC with drugs such as rilotumumab, foretinib, and crizotinib. Further identification and validation of prognostic and predictive biomarkers has the potential transform how this deadly disease is managed.

Clinical significance of expression of IGF-1R and IGF-1 in gastric cancer

AIM: To investigate the expression of insulin-like growth factor type 1 receptor (IGF-1R) and IGF-1 in gastric cancer and to analyze the relationship between their expression and the clinicopathologic features.

METHODS: The expression of IGF-1R and IGF-1 proteins was detected by immunohistochemistry in 70 gastric cancer tissues and matched tumor adjacent tissues. The relationship between the expression of IGF-1R and IGF-1 and clinicopathologic parameters including gender, age, tumor diameter, site, differentiation, Borrmann type, infiltration depth, lymph node metastasis and TNM stage was then analyzed.

RESULTS: The positive rates of IGF-1R/IGF-1 expression in gastric cancer (55.17%/52.86%) were significantly higher than those in control tissue (25.00%/15.63%) (P < 0.05). IGF-1R expression was closely correlated with tumor differentiation, infiltration depth, lymph node metastasis and TNM stage (P < 0.05). IGF-1 expression was closely correlated with tumor infiltration depth, lymph node metastasis and TNM stage (P < 0.05). The expression of IGF-1R was positively correlated with that of IGF-1 in gastric cancer (r = 0.310, P < 0.01).

CONCLUSION: Over-expression of IGF-1R exists in gastric cancer and is correlated with tumor differentiation, infiltration depth, lymph node metastasis and TNM stage. Over-expression of IGF-1 also exists in gastric cancer and is correlated with infiltration depth, lymph node metastasis and TNM stage. Overexpression of IGF-1R and IGF-1 may be related to the development of gastric cancer. There is a positive correlation between IGF-1R and IGF-1 expression in gastric cancer, suggesting a synergistic effect between them in the development of gastric cancer. They may become new markers for gastric cancer.

The prognostic value of ERCC1 expression in gastric cancer patients treated with platinum-based chemotherapy: a meta-analysis

Numerous studies examined the association between excision repair complementation group 1 (ERCC1) expression and the prognosis of gastric cancer patients receiving platinum-based chemotherapy but yielded controversial results. We thus conducted a meta-analysis to quantitatively evaluate the prognostic value of ERCC1 expression in gastric cancer patients receiving platinum-based chemotherapy. A systematic literature search was performed to identify relevant studies in PubMed, Web of Science, Embase, Cochrane Library, China National Knowledge Infrastructure, Chinese Biomedical Literature Database, and WanFang Database up to December 17, 2013. Pooled hazard ratios (HRs) or odds ratios (ORs) with 95 % confidence intervals (CIs) were estimated. Moreover, meta-regression analysis and subgroup analysis were conducted according to ethnicity, HR extraction, detection methods, survival analysis, and quality score. A total of 1,409 patients from 21 studies were subjected to final analysis. Positive/high ERCC1 expression was significantly associated with poorer overall survival (HR, 1.58; 95 % CI, 1.09-2.28), especially in Asians (HR, 1.81; 95 % CI, 1.20-2.73), and lower response rate (OR, 0.26; 95 % CI, 0.18-0.36), but not with clinicopathological features, such as gender (OR, 1.01; 95 % CI, 0.68-1.51), grade (OR, 0.66; 95 % CI, 0.43-1.01), and stage (OR, 1.05; 95 % CI, 0.58-1.90). This meta-analysis suggested that ERCC1 expression might be a useful biomarker to predict response and survival for gastric cancer patients receiving platinum-based chemotherapy, particularly in Asians.

Molecular profiling in gastric cancer: examining potential targets for chemotherapy

BACKGROUND AND OBJECTIVES

Current NCCN guidelines recommend epirubicin (E), cisplatin (C), and 5-fluorouracil (F) as a first-line therapeutic approach for operable gastric adenocarcinoma (GC). Molecular profiling (MP) was used to evaluate the expression of chemotherapy targeted biomarkers associated with ECF therapy and other first-line cytotoxic regimens for GC.

METHODS

GC specimens were analyzed by immunohistochemistry (IHC) for TOP2A, TS, ERCC1, PGP, and TOPO1 expression (Caris Life Sciences, Phoenix, AZ) from 2009 to 2012.

RESULTS

A total of 230 GC specimens were analyzed. The median age of patients was 61 (IQR: 50-72) years with the majority being male (n = 139, 60%). IHC actionable targets included: 60% (n = 138) high TOP2A, 55% (n = 127) negative ERCC1, and 63% (n = 145) negative TS, indicating potential benefit from E, C, and F, respectively. Simultaneous expression analysis demonstrated only 24% (n = 55) of patients had gene expression levels that suggested uniform sensitivity to ECF. Biomarker results of 6.5% (n = 15) of patients revealed a potential complete lack of sensitivity to first-line ECF.

CONCLUSIONS

MP of GC has the potential to define patients who would derive the greatest benefit from current therapies. Prospective controlled studies are required to validate the role of biomarkers in the management of GC patients.

Overexpression of GNAO1 correlates with poor prognosis in patients with gastric cancer and plays a role in gastric cancer cell proliferation and apoptosis

Guanine nucleotide-binding protein (G protein), alpha activating activity polypeptide O (GNAO1) encodes an alpha subunit of the heterotrimeric guanine nucleotide-binding proteins (Gαo), which plays a significant role in the development of various types of cancer, including breast cancer and hepatocellular carcinoma. However, its role in gastric cancer (GC) has not yet been elucidated. In the current study, the expression of Gαo was analyzed by immunohistochemistry in paraffin-embedded tissue sections from 70 patients with GC and its cellular role was examined by small interfering RNA (siRNA)-mediated downregulation. The overexpression of GNAO1 (scores of 2 or 4) was observed in 44 of the 70 patients with GC (62.9%) and the expression of Gαo significantly correlated with the overall survival of the patients with GC after surgery. The median survival rate of patients with a negative or positive expression of Gαo was 61 or 27 months, respectively (P=0.033). The silencing of GNAO1 in GC cells by RNA interference markedly inhibited the proliferation of GC cells and promoted apoptosis by increasing the accumulation of the pro-apoptotic proteins, Puma and Bim, possibly mediated by extracellular signal-regulated kinase 1 and 2 (ERK1/2). This further confirmed the clinical significance of GNAO1, which was overexpressed in GC tissues. To the best of our knowledge, the present study is the first to demonstrate that GNAO1 is overexpressed in GC and that its overexpression correlates with poor prognosis, as it promotes GC cell viability.