Several studies have investigated the association between CYP3A5 FNx01 3 genetic polymorphism and acute lymphoblastic leukemia (ALL) risk in children, but have yielded controversial results. Therefore, we performed a meta-analysis to evaluate synthetically the effect of CYP3A5 FNx01 3 polymorphism on the risk of ALL in children.

Runt-related transcription factor 3 (RUNX3) has been reported to be a tumor-suppressing gene in hepatocellular carcinoma. Association between hepatocellular carcinoma and RUNX3 promoter methylation has been investigated in studies with specific ethnic backgrounds and small sample sizes. In this study, a meta-analysis was adopted to combine the data from 11 studies of association between RUNX3 promoter methylation and hepatocellular carcinoma. Pooled odds ratio for RUNX3 promoter methylation status in hepatocellular carcinoma versus control liver tissue was 24.37 (95%CI: 12.14, 48.92), p < .00001, indicates a strong association between methylation of the RUNX3 promoter and hepatocellular carcinoma.

To investigate the association between hypoxia-inducible factor-1α (HIF-1α) polymorphisms (-1772C>T and -1790G>A) and the risk of digestive tract cancer.

Despite improvements in both diagnostic and therapeutic strategies, the prognosis of oral squamous cell carcinoma (OSCC) has not changed significantly over the last decades. Prognosis of OSCC particularly depends on the presence of nodal metastasis in the neck. Therefore, proper determination of the nodal status is pivotal for appropriate treatment. Unfortunately, current available imaging techniques (magnetic resonance imaging or ultrasound even with fine needle aspiration of suspected lymph nodes (LNs)) fail to detect occult nodal disease accurately. Clinicians in head and neck oncology urgently need new diagnostic tools to reliably determine the presence of nodal metastasis of the neck. Gain of the chromosomal region 11q13 is one of the most prominent genetic alterations in head and neck cancer and is associated with poor prognosis and metastasis. The aim of this systematic review and meta-analysis was to determine the diagnostic value of either 11q13 amplification or amplification/protein overexpression of individual genes located on 11q13 to detect nodal metastasis in OSCC. A search was conducted in Pubmed, EMBASE, and Cochrane, and 947 unique citations were retrieved. Two researchers independently screened all articles and only 18 were found to meet our inclusion criteria and were considered of sufficient quality for meta-analysis. Pooled results of those show that both amplification of CCND1 and protein overexpression of cyclin D1 significantly correlate with lymph node metastasis (LNM) in OSCC. In addition, amplification of CCND1 shows a negative predictive value of 80 % in the detection of LNM in early stage OSCCs which are clinically lymph node negative although this evidence is sparse and should be validated in a larger homogeneous cohort of T1-2 OSCC.

Non-small cell lung cancer (NSCLC) patients harboring KRAS mutation were associated with worse prognosis and lower response to epidermal growth factor receptor (EGFR) target therapy than those with wild-type tumors. However, whether the underlying biological differences are associated with the efficacy of cytotoxic chemotherapy in advanced NSCLC patients remained controversial. We searched electronic databases for eligible literatures. The primary outcomes were objective response rate (ORR), 6-month and 1-year progression-free survival (PFS) rate. The pooled odds ratio (OR) was calculated using random-effect model. Subgroup analyses stratified by literature type, mutation analysis method, therapeutic regimen, patient origin, and EGFR mutation status in KRAS wild-type patients were proposed. Heterogeneity and publication bias were quantitatively evaluated. A total of ten studies involving 1,677 advanced NSCLC patients with known KRAS mutation status who had received first-line chemotherapy were included. KRAS mutants had lower ORR than wild-type patients (25.1 vs. 34.4%) significantly (OR 0.67, 95% CI 0.50-0.88, P = 0.004). Additionally, patients with KRAS mutation had numerically lower 6-month (51.0 vs. 56.8%) and 1-year (10.3 vs. 13.3%) PFS rate than wild-type patients, but there was no significant difference between the two groups (OR 0.75, 95% CI 0.54-1.04, P = 0.08; OR 0.75, 95% CI 0.47-1.21, P = 0.25). Results of the subgroup analyses were almost concordant with the overall ones. This comprehensive analysis revealed that advanced NSCLC patients with KRAS mutations had significantly lower ORR and potentially lower 6-month/1-year PFS rate compared with wild-type patients after first-line chemotherapy.

FAS and FAS ligand (FASL) are the principal genes of the apoptosis pathway, which play a vital role in the etiology of various gynecological cancers. Studies have revealed that polymorphism of FASL promoter -844C>T (rs763110) influences FASL transcription process, which involving in cancer risk. Moreover, estrogen has been proved to trigger T-cell apoptosis by up-regulating FAS/FASL system in cancer cells. However, results from the published studies on the association between FASL -844C>T polymorphism and risk of gynecological cancer are conflicting. We performed a meta-analysis based on 13 case-control studies, including a total of 6256 cancer cases and 5573 controls. We used odd ratios (ORs) with 95% confidence intervals (CIs) to assess the association strength. Overall, the FASL -844CT and TT genotypes were associated with a significantly reduced risk of gynecological cancer types in homozygote comparison (OR=0.80, 95% CI=0.64-0.99), heterozygote comparison (OR=0.81, 95% CI=0.67-0.98), and dominant model (OR=0.81, 95% CI=0.67-0.98). In the stratified analyses, we observed a similar association among Asian population (heterozygote comparison: OR=0.73, 95% CI=0.56-0.95; dominant model: OR=0.75, 95% CI=0.57-0.98) and hospital-based studies (homozygote comparison: OR=0.61, 95% CI=0.43-0.86). When stratified by cancer type, there was also a significantly lower risk of the ovarian cancer in different genetic models except the recessive one. The results suggested that the FASL -844C>T polymorphism may reduce the risk of gynecological cancer.

Acute lymphoblastic leukemia (ALL) is the most common malignancy in children, though the etiology of the leukemia is poorly understood, both genetic and environmental factors appear to be involved. Previous studies investigating the association between MDR1 C3435T polymorphisms and risk of children with ALL reported controversial results.

Univariate analyses from several randomized phase III trials seemed to suggest ever-smokers with advanced mutated epidermal growth factor receptor (EGFRm) non-small cell lung cancer (NSCLC) did not seem to benefit from EGFR tyrosine kinase inhibitors (TKIs) as first-line treatment when compared with platinum-doublet chemotherapy as measured by progression-free survival (PFS).

Previous studies have showed that ABO blood type is associated with multiple gastrointestinal cancers, including pancreatic cancer. Recently, one single nucleotide polymorphism (SNP) rs505922 in ABO gene has been implicated in susceptibility to pancreatic cancer across different populations, but different results were found in other types of cancer. This meta-analysis aimed to clarify the association. All eligible case-control studies were identified by searching through PubMed and Chinese language databases (CNKI and WanFang) up to September 1, 2014. Pooled estimates (odds ratio) were used to assess the strength of associations in fixed- or random-effects models. A total of nine studies with 10,304 cases and 15,564 controls were included. Overall, SNP rs505922 C allele was confirmed as a risk factor for cancer. Additionally, in further stratified analysis by cancer type, C allele carriers were more likely to have higher risk of pancreatic cancer. This study provided evidence of SNP rs505922 C allele as a strong risk factor of cancer susceptibility, specifically for pancreatic cancer.

Epigenetic silencing of tumor suppressor genes by promoter methylation plays vital roles in the process of carcinogenesis. The purpose of this meta-analysis was to determine whether the aberrant methylation of cyclin A1 (CCNA1) may be of great significance to human malignant tumors. By searching both English and Chinese language-based electronic databases carefully, we tabulated and analyzed parameters from each study. All human-associated case-control studies were included providing available data for CCNA1 methylation and reporting the adjusted odds ratios (ORs) and 95% confidence intervals (CI) conducted with the use of Version 12.0 STATA software. A total of 10 case-control studies (619 patients with cancers and 292 healthy controls) were included for the following statistical analysis. Pooled OR values from all articles revealed that the frequency of CCNA1 methylation in cancer tissues was significantly higher than those of normal tissues (P < 0.001). Further ethnicity indicated that the frequency of CCNA1 methylation was correlated with the development of malignant tumors among all those included experimental subgroups (all P < 0.05). These data from results indicated a significant connection of CCNA1 methylation with poor progression in human malignant tumors among both Caucasian and Asian populations.

Previous studies showed that isocitrate dehydrogenase 1 (IDH1) mutation might be a prognostic biomarker of prognosis in glioblastoma (GBM) patients, but the outcomes were various. A meta-analysis of published studies was carried out to reach a reliable assessment of the association between IDH1 mutation and mortality of GBM patients. Relative risks (RRs) with 95% confidence intervals (95%CIs) were pooled using meta-analysis to assess risk of mortality in patients with IDH1 mutation. A total of 20 studies (3 prospective cohort and 17 retrospective cohort studies) were finally included into the meta-analysis. Meta-analysis of total included studies suggested that GBM patients with IDH1 mutation had decreased risk of mortality compared those patients without IDH1 mutation (RR = 0.43, 95%CI 0.35-0.54, P < 0.001). GBM patients with IDH1 mutation from European countries had also decreased mortality risk compared with those patients without IDH1 mutation (RR = 0.35, 95%CI 0.25-0.49, P < 0.001), but GBM patients with IDH1 mutation from Asians only dad 32% decrease of mortality risk compared with those patients without IDH1 mutation (RR = 0.68, 95%CI 0.49-0.94, P = 0.018). The findings from the meta-analysis provide strong evidence for the association between IDH1 mutation and decreased mortality risk of GBM patients. In addition, there is an obvious difference in the mortality risk of GBM patients with IDH1 mutation between western and eastern countries.

Data from previous studies about the association between interferon gamma (IFN-γ) +874 T/A (rs2430561) polymorphism and cervical cancer risk offer controversial results. To obtain a more dependable conclusion, this meta-analysis was performed. We selected eight articles including nine case-control studies with 1,116 cases and 1,290 controls, odds ratios (OR) with 95 % confidence intervals (CI) were used to assess the strength of the association. Subgroup analysis was carried out by ethnicity, source of controls, genotyping methods, and score of quality assessment. Our meta-analysis indicated that the IFN-γ (+874 T/A) polymorphism significantly increased the risk of cervical cancer in the codominant model (TA vs. TT: OR = 1.471, 95 % CI = 1.137-1.903, P = 0.003, I (2) % = 0.0, P Q  = 0.785) and the dominant model (TA + AA vs. TT: OR = 1.399, 95 % CI = 1.097-1.784, P = 0.007, I (2) % = 0.0, P Q  = 0.486) in the overall population. Stratified analysis by ethnicity indicated a significantly increased risk of cervical cancer in Asians in the codominant model (TA vs. TT: OR = 1.494, 95 % CI = 1.069-2.087, P = 0.019, I (2) % = 0.0, P Q  = 0.440) and the dominant model (OR = 1.455, 95 % CI = 1.062-1.993, P = 0.019, I (2) % = 42.9, P Q  = 0.154). Thus, the IFN-γ (+874 T/A) polymorphism is likely to increase the risk of cervical cancer. Because of the limited studies and sample sizes included in our meta-analysis, further well-designed and large-scale studies are demanded to confirm our results.

To determine the efficacy of first-generation epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) in advanced non-small cell lung cancer (NSCLC) patients with wild-type (WT) EGFR tumors, we performed an indirect meta-analysis to assess the treatment effects of EGFR-TKIs in such patients.

Epidemiological studies indicate a genetic contribution to colorectal cancer (CRC), but specific genetic variants remain unknown. Genome-wide association studies have identified rs4444235 at BMP4 as a new colorectal cancer (CRC) and colorectal adenoma (CRA) susceptibility locus in populations of European descent. After that, several validation studies have been conducted among various ethnic populations to investigate if the SNP was associated with CRC/CRA, but the results have been inconsistent. To investigate this inconsistency and derive a more precise estimation of the relationship, a meta-analysis involving 54,631 CRC cases, 3995 CRA cases and 88,098 controls from 15 studies was performed. Potential sources of heterogeneity including ethnicity, sample size, study design and endpoint were also assessed. Overall, the summary OR of CRC was 1.06 (95% CI: 1.04-1.08, P<10(-5)). In the subgroup analysis by ethnicity, significantly increased risks were found in East Asians (OR=1.07, 95% CI: 1.01-1.12, P=0.01) and Caucasians (OR=1.07, 95% CI: 1.05-1.10, P<10(-5)); while no significant associations were found among African Americans and other ethnic populations in all genetic models. In addition, significant associations were also detected for CRA with per-allele OR of 1.09 (95% CI: 1.03-1.14, P=0.001). Our findings demonstrated that BMP4-rs4444235 is a risk factor associated with increased CRC and CRA susceptibility, but these associations vary in different ethnic populations.

Deletion types of genetic variants of glutathione S-transferase (GST) M1 and T1, the GSTM1 null and GSTT1 null which are risk factors for certain cancers, have been ubiquitously found in human populations but their worldwide distribution pattern is unclear.

Epidemiologic findings concerning the association between the hsa-mir-499 rs3746444 A>G polymorphism and cancer risk have yielded mixed results. We aimed to investigate the association by performing a meta-analysis of all available studies. We searched PubMed and EMBASE for studies published up to November 2014, using odds ratios (ORs) with 95% confidence intervals (CIs) to assess the strength of any association. The Benjamini- Hochberg (BH) method was used to correct the p values for multiple comparisons. We included 39 studies, including 14,136 cases and 16,937 controls. The results of overall meta-analysis suggested a borderline association between hsa-mir-499 rs3746444 polymorphism and cancer susceptibility (AG+GG vs. AA: OR=1.15, 95% CI= 1.04-1.26, corrected p value=0.04). After removing studies not conforming to Hardy-Weinberg equilibrium (HWE), however, this association disappeared (AG+GG vs AA: OR=1.18, 95% CI=1.03-1.34, corrected p value=0.21). When stratified analysis by ethnicity, cancer type or HWE in controls, although some associations between hsa-mir-499 rs3746444 polymorphism and cancer susceptibility were detected, these associations no longer existed after adjustment using BH method. In conclusion, our meta-analysis suggests that hsa-mir-499 rs3746444 A>G polymorphism is not associated with risk of cancer based on current evidence.

Gastric cancer is one of the frequently seen cancers in the world and it is the second most common reason for death due to cancer. The prognostic role of expression of p53 detected by immunohistochemistry in gastric cancer remains controversial. This meta-analysis aimed to explore any association between overexpression and survival outcomes.

DICER, one of the microRNA (miRNA) biogenesis proteins, is involved in the maturation of miRNAs and is implicated in cancer development and progression. The results from previous epidemiological studies on associations between DICER rs1057035 polymorphism and cancer risk were inconsistent. Thereforewe performed this meta-analysis to summarize possible associations.

Current data on the concordance of KRAS, BRAF, PIK3CA mutation status or PTEN expression status between primary tumors and metastases in colorectal cancer (CRC) are conflicting. We conducted a systematic review and meta-analysis to examine concordance and discordance of the status of these four biomarkers between primary tumors and corresponding metastases in CRC patients. The biomarker status in primary tumors was used as the reference standard. Concordance data for KRAS, BRAF, PIK3CA and PTEN were provided by 43, 16, 9 and 7 studies, respectively. The pooled concordance rate was 92.0% (95% CI: 89.7%-93.9%) for KRAS, 96.8% (95% CI: 94.8%-98.0%) for BRAF, 93.9% (95% CI: 89.7%-96.5%) for PIK3CA and 71.7% (95% CI: 57.6%-82.5%) for PTEN. The pooled false positive and false negative rates for KRAS were 9.0% (95% CI: 6.5%-12.4%) and 11.3% (95% CI: 8.0%-15.8%), respectively. KRAS, BRAF and PIK3CA mutations are highly concordant between primary tumors and corresponding metastases in CRC, but PTEN loss is not. Nine percent of patients with wild-type KRAS in primary tumors who received anti-EGFR treatment had mutant KRAS in metastases, while 11.3% patients with mutant KRAS primary tumors had wild-type KRAS in the metastases. These 11.3% patients currently do not receive potentially beneficial anti-EGFR treatment.

Recent studies have shown that c-Met is an important signal in the development of colorectal cancer, but the prognostic value of c-Met remains unclear. We aimed to analyze the prognostic effect of c-Met in colorectal cancer through a systematic review and meta-analysis. Through database searches, we identified six articles describing how c-Met status affects colorectal cancer prognosis. A meta-analysis was performed to investigate the relationship between the hazard ratio and survival. The available outcome data from six articles were examined. A meta-analysis of the HR and the 95% confidence interval (CI) indicated a significantly poor overall survival and disease-free survival in patients with high expression levels of c-Met. The subgroup analysis showed that the prognostic effect of the c-Met level was similar in different methods and was not associated with disease stages. High c-Met expression levels could predict a poor prognosis in colorectal cancer patients. The c-Met status could be used to evaluate the prognosis in clinical patients.