Manganese superoxide dismutase polymorphism and prostate cancer risk: a meta-analysis

Objective: MnSOD plays a vital role in carcinogenesis, partly in that it converts superoxide radical to oxygen and hydrogen peroxide. The conflicting results of studies on the role of MnSOD polymorphism (Val-9Ala) with the risk of prostate cancer encouraged us to perform a meta-analysis to examine the association. Methods: A comprehensive search was conducted to examine all the eligible studies of MnSOD polymorphism and prostate cancer risk. We used odds ratios (ORs) with 95% confidence intervals (CIs) to assess the strength of the association. The pooled estimates of ORs were computed using the fixed-effects model or random-effects model. Results: Ten eligible studies, including 4 608 cases and 5 861 controls, were included in this meta-analysis. Overall, individuals with Ala/Ala and Ala/Val genotypes have an increased risk of prostate cancer, compared with those carrying the Val/Val genotype (Ala/Ala vs. Val/Val: OR=1.13; 95% CI=1.02～1.25; P = 0.020, Pheterogeneity=0.370; Ala/Val vs. Val/Val: OR=1.14; 95% CI=1.04～1.25; P = 0.004, Pheterogeneity=0.940). This significant association was also found in a dominant model with -9Ala allele (Ala/Ala＋Ala/Val vs. Val/Val: OR=1.12; 95% CI: 1.03～1.22; P = 0.009, Pheterogeneity=0.64). In the subgroup by ethnicity, it was observed that significantly elevated prostate cancer risk was associated with -9Ala allele in Caucasians (Ala/Ala vs. Val/Val: OR=1.14; 95% CI=1.03～1.27; P = 0.01, Pheterogeneity=0.31; Ala/Val vs. Val/Val: OR=1.14; 95% CI=1.04～1.24; P = 0.006, Pheterogeneity=0.87) but not in African-Americans. Furthermore, this meta-analysis showed that the -9Ala allele was associated with both nonaggressive and aggressive prostate cancer risks. Conclusion: Our meta-analysis suggests that MnSOD Val-9Ala polymorphism is associated with prostate cancer risk, especially in Caucasians.     

Vitamin D status and the risk of pancreatic cancer: a meta-analysis

Background Vitamin D status in relation to pancreatic cancer risks is still inconsistent.This study was performed to evaluate the association between vitamin D status and risk of pancreatic cancer usin...     

MicroRNA与非小细胞肺癌

肺癌已经成为全球范围内因癌症导致死亡的首要原因,当今由于缺乏有效的指导临床诊断和治疗的肿瘤分子标志物,所以非小细胞肺癌患者的疗效不佳。Micro RNA(以下简称miRNA)是真核生物中一类长度约为22个核苷酸的参与基因转录后水平调控的小分子非编码RNA。miRNA在肺癌中发挥原癌基因及抑癌基因的作用,在肺癌的发生、发展过程中均发挥着重要作用。miRNA不仅可以在石蜡包埋组织和体液中保持稳定,而且在血清和血浆中也可以稳定存在,这个特性使循环miRNA有望成为一种新型分子标志物,为肺癌的早期分子诊断、预测预后及治疗效果开辟了一个新的研究领域。     

P53 codon 72 polymorphism and ovarian cancer risk： a meta-analysis

Objective:p53 is a tumor suppressor gene and is involved in the etiology of ovarian cancer.Studies investigating the associations between the p53 codon 72 polymorphism and ovarian cancer risk showed conflicting results.We performed this meta-analysis from eligible studies to evaluate this purported relationship.Methods:This meta-analysis was performed from 9 case-control studies, including 825 ovarian cases and 1073 controls.The fixed and random effect models were used to estimate the odds ratios(ORs)for various contrasts of this polymorphism.Results:The combined results based on all studies showed that a significantly decreased risk was associated with the variant Pro/Pro genotype,compared with Arg/Pro Arg/Arg genotypes(OR,0.70;95%CI,0.51~0.95).When stratifying the studies by ethnicity,we found that individuals with the variant genotype Pro/Pro had a significantly decreased risk of ovarian cancer compared with Arg/Arg genotype(OR,0.43;95%CI,0.20~0.89)and Arg/Pro Arg/Arg genotypes(OR,0.61;95%CI, 0.37~0.99)among Africans.Conclusion:This meta-analysis suggests that the p53 codon 72 polymorphism may contribute to genetic susceptibility to ovarian cancer.More studies based on larger sample size should be performed to confirm the findings.     

MicroRNA在肺癌诊断和治疗方面的研究进展

MicroRNA（miRNA）是一类长21～25个核苷酸的小分子非编码RNA,通过与特定mRNA 3＇UTR结合抑制蛋白质表达参与生物的发育、代谢及肿瘤的发生、发展等生命现象。近年来,越来越多的研究显示miRNA与肺癌的诊断、治疗关系密切,可作为肺癌早期诊断的生物标志物,还可能成为肺癌靶向治疗的有效靶点。本文结合国内外最新报道,综述miRNA在肺癌诊断、治疗方面的研究进展。     

Chemotherapy with or without gefitinib in patients with advanced non-small-cell lung cancer: a meta-analysis of 6844 patients

Background Gefitinib is widely used in patients with advanced non-small-cell lung cancer （NSCLC）, in whom chemotherapy had failed. Previous trials reported inconsistent findings regarding the efficacy of gefitinib on overall survival （OS） and progression free survival （PFS）. This study was to evaluate the effects of chemotherapy plus gefitinib versus chemotherapy alone on survival of patients with NSCLC. Methods We systematically searched Medline, EmBase, the Cochrane Central Register of Controlled Trials, reference lists of articles, and proceedings of major meetings for relevant literature. Randomized controlled trials （RCTs） comparing chemotherapy with and without gefitinib in the treatment of patients with advanced NSCLC were included in our analysis. The primary endpoints were OS and PFS. Results Of 182 relevant studies, 12 were included in the final analysis, which consisted of 6844 patients with NSCLC. Overall, we noted that gefitinib therapy had an 8% improvement in the OS as compared to the gefitinib-free therapy, but this difference was not statistically significant （HR, 0.92; 95% CI： 0.85-1.00; P=0.051）. Furthermore, gefitinib therapy had significantly longer PFS compared to gefitinib-free therapy （HR, 0.72; 95% CI 0.60-0.87, P=0.001）. Patients receiving gefitinib therapy also had a more frequent objective response rate （ORR） than the control arm （OR, 2.51; 95% CI, 1.67- 3.78, P 〈0.001）. Rashes, diarrhea, dry skin, pruritus, paronychia, and abnormal hepatic function were more frequent in the gefitinib therapy group. Conclusions Treatment with gefitinib had a clear effect on PFS and ORR, and it might contribute considerably to the OS. Furthermore, there was some evidence of benefit for gefitinib therapy among patients with adenocarcinoma.     

Thymidylate synthase genetic polymorphisms and cancer risk: a meta-analysis of 37 case-control studies

Background  Several studies have evaluated the association between polymorphisms of thymidylate synthase (TS) and cancer risk in diverse populations but with conflicting results. By pooling the relatively small samples in each study, it is possible to evaluate the association using a meta-analysis.

Methods  A comprehensive search was conducted to identify all case-control studies on TS on a 28-bp tandem repeats in 5′untranslated region (5′UTR) and a 6-bp insertion (ins) and deletion (del) mutation in 3′UTR of the gene and cancer risk. Meta-analysis was conducted using a fixed and random effect model.

Results  Our meta-analysis on a total of 13 307 cancer cases and 18 226 control subjects from 37 published case-control studies showed no significant association between the risk of cancer and the 5′UTR 28-bp tandem repeats polymorphism (3R/3R vs. 2R/2R: OR=1.06, 95% CI, 0.93–1.20) or the 3′UTR 6-bp ins/del polymorphism (del6/del6 vs. ins6/ins6: OR=0.93, 95% CI, 0.81–1.08) with significant between-study heterogeneity. In the cancer type- and ethnic subgroup-stratification analyses, we did not find any association between TS polymorphisms and cancer risk either.

Conclusion  TS 5′UTR 28-bp tandem repeats and 3′UTR 6-bp ins/del polymorphisms may not be associated with cancer risk.     

谷胱甘肽S转移酶T1基因多态性与口腔癌易感性的meta分析

目的:通过既往相关研究,综合评价谷胱甘肽S转移酶T1(glutathione S-transferase class Theta-1,GSTT1)基因多态性与口腔癌易感性间的关联?方法:根据系统评价的原理和规范,检索PubMed数据库,纳入GSTT1基因与口腔癌的病例对照研究?根据种族,采用分层Meta分析评估GSTT1基因多态性与口腔癌的关联性,同时评估发表偏倚?结果:Meta分析显示,GSTT1基因多态性与口腔癌总的效应为OR=1.17(95%CI:0.87~1.58)?进一步亚组分析显示,亚洲人种OR=0.99 (95%CI:0.71~1.36);高加索人种OR=1.07 (95%CI:0.69~1.64);混合人种OR=1.89 (95%CI:0.76~4.67)?结论:尚不能认为GSTT1基因多态性能影响口腔癌的易感性,这一结论尚需要大规模?多种族的流行病学或功能学研究验证?     

Chemotherapy with or without irinotecan in patients with advanced or recurrent gastric cancer: a meta-analysis of randomized controlled trials

Background Studies have shown that irinotecan can improve survival in patients with advanced or recurrent gastric cancer,but the overall benefit of irinotecan in the treatment of advanced or recurrent gastric cancer remains controversial.The aim of this study was to evaluate the benefits and risks of irinotecan for survival in patients with advanced or recurrent gastric cancer.Method We searched PubMed,EmBase,the Cochrane Central Register of Controlled Trials,reference lists of articles,and proceedings of major conferences for relevant clinical trials.We included randomized controlled trials that reported on the efficacy and safety of irinotecan in patients with advanced or recurrent gastric cancer.Outcomes were analyzed by survival rate,objective response rate （ORR）,and toxicity.Furthermore,the analysis was further stratified by factors that could affect the treatment effects.Results Eight trials recruiting 1 546 patients with advanced or recurrent gastric cancer were included in the analysis.Overall,irinotecan therapy was associated with a 6％ improvement in survival rate,but this difference was not statistically significant （odds ratio （OR） 0.94; 95％ confidence interval （95％ CI） 0.70-1.27; P=-0.69）.However,irinotecan therapy had more frequent ORR than irinotecan-free arm （OR 1.70; 95％ CI 1.34-2.17; P ＜0.001）.Furthermore,irinotecan therapy was associated with a clinically and statistically significant increase in the risk for declined hemoglobin,hyponatremia,and diarrhea,but it also protected against thrombocytopenia risk when compared with irinotecan-free therapy.Conclusions There is no evidence to support the use of irinotecan therapy in patients with advanced or recurrent gastric cancer; however,given the significant advantage in ORR irinotecan therapy using combination regimens may be considered for further evaluation in subsets of patients who may benefit from this treatment.     

丝裂霉素对胃癌细胞SGC-7901miRNA表达谱的影响

目的 分析丝裂霉素(MMC)治疗对胃癌细胞miRNA表达谱的影响,为MMC的胃癌治疗机制提供理论参考。方法 体外培养胃癌SGC-7901细胞,根据噻唑兰(MTT)法评估MMC的作用效果和作用浓度;利用miRNA芯片技术评估MMC干预后SGC-7901的miRNA表达谱改变,并通过qRT-PCR验证差异表达miRNA。 结果 SGC-7901细胞生长抑制率与MMC作用浓度间存在正相关;MMC干预48 h后SGC-7901细胞有59个miRNA出现表达改变,与正常胃黏膜上皮细胞GES-1相比,SGC-7901胃癌细胞的miR-205*和miR-3924等11个miRNAs表达上调,而miR-498,miR-18b,miR-196b,miR-1247等22个miRNA表达下调;经MMC干预后,部分异常表达得到恢复。 结论 MMC可能调控miR-498在内的59个miRNA在胃癌细胞的表达。     

CYP17 T27C polymorphism and prostate cancer risk:a meta-analysis based on 31 studies

Objective: The cytochrome P450 17α-hydroxylase (CYP17) plays a vital role in androgen biosynthesis. A T-to-C polymorphism in the 5' promoter region of CYP17 has been implicated as a risk factor for prostate cancer, but the results of individual studies are inconclusive or controversial. To derive a more precise estimation of the relationship, we performed an updated meta-analysis from 31 studies based on 27 publications. Methods: A comprehensive search was conducted to examine all the eligible studies of CYP17 polymorphism and prostate cancer risk. We used odds ratios (ORs) with 95% confidence intervals (CIs) to assess the strength of the association. Results: Overall, individuals with CC/CT genotype were not associated with prostate cancer risk (CC vs. TT: OR = 1.03, 95% CI = 0.86-1.24, P = 0.72, Pheterogeneity < 0.0001; CT vs. TT: OR = 0.99, 95% CI = 0.87-1.12, P = 0.88, Pheterogeneity = 0.0006). In the stratified analysis by ethnicity, there was a significantly increased risk of prostate cancer among individuals of African descent under the recessive model (OR = 1.56, 95% CI = 1.01-2.39, P = 0.04, Pheterogeneity = 0.65). Conclusion: This meta-analysis suggested that CYP17 polymorphism might be associated with prostate cancer risk among individuals of African descent.     

Nitrate in drinking water and bladder cancer: A meta-analysis

This study examined whether exposure to nitrate in drinking water is associated with increased risk for bladder cancer by conducting a comprehensive literature research. A meta-analysis was performed with and without adjustment for confounding factors. Three groups (reference, intermediate and high groups) were established in terms of different nitrate concentrations in each included study. Separate relative risk measures were calculated for intermediate and high groups. Heterogeneity was assessed by using the Q statistics. Publication bias was evaluated by Egger’s and Begg’s test. Quality assessment for studies was performed by using the Newcastle-Ottawa scale. Two cohorts, two case-controls, and one ecological study were included in this study. The adjusted data showed that the combined risk ratios (RRs) were 1.13 (95% CI: 0.81 to 1.57) and 1.27 (95% CI: 0.75 to 2.15) for inter-mediate and high groups respectively. For unadjusted data, the corresponding RRs were 1.18 (95% CI: 0.89 to 1.57) and 1.29 (95% CI: 0.81 to 2.07). Sensitivity test indicated that results were significantly underestimated when Ward’s study was included. No significant publication bias was found. There was heterogeneity among studies. The results suggested that there was no sufficient evidence that nitrate in drinking water is associated with increased risks for bladder cancer.     

新辅助内分泌联合治疗与单纯根治性手术对前列腺癌预后和疗效的Meta分析

目的 系统评价新辅助内分泌治疗局限性前列腺癌的有效性.方法 计算机检索Cochrane图书馆、PubMed、EMBASE、中国生物医学文献数据库、中国期刊全文数据库、中文科技期刊数据库和万方数据库.检索时间为1993-2010年.并追查已纳入文献的参考文献.收集有关新辅助内分泌治疗与单纯根治性手术治疗前列腺癌的随机对照...     

Association between p53 Pro72Arg polymorphism and prostate cancer risk:a meta-analysis

The tumor suppressor gene p53 appears to be important in the development of many human cancers, such as prostate cancer. The association of p53 codon72 polymorphism with prostate cancer has been widely reported; however, the results are inconsistent. To derive a more precise estimation of this relationship, we performed an updated meta-analysis from 10 case-control studies. We conducted a search in the PubMed database without a language limitation, covering all papers published until July 2010. Risk ratios ...     

miR-210高表达与乳腺癌预后关系的meta分析

目的:探讨miR-210高表达与乳腺癌患者预后的关系?方法:检索PubMed?EMBASE?Web of Science和CNKI等数据库中关于miR-210高表达与乳腺癌预后关系的文献资料,按纳入标准筛选出相关文献,提取总生存率 (overall survival,OS)?无复发生存率(recurrence-free survival,RFS)和无病生存率(disease-free survival,DFS)的风险比(hazard ratio,HR)及其95%可信区间(CI),用Stata软件进行分析合并?结果:按标准共纳入文献6篇,病例数585例,meta分析显示:和低表达组相比,miR-210高表达组OS的合并HR值为2.29(95%CI:0.89~5.91,P=0.086);miR-210高表达组DFS/RFS的合并HR值为2.81(95%CI:1.35~5.87,P=0.006)?结论:以现有相关研究结果的meta分析显示,miR-210的高表达是乳腺癌临床预后的不良因素?     

CYP17 T27C polymorphism and prostate cancer risk： a meta-analysis based on 31 studies

Objective：The cytochrome P450 17α-hydroxylase（CYP17）plays a vital role in androgen biosynthesis.A T-to-C polymorphism in the 5＇promoter region of CYP17 has been implicated as a risk factor for prostate cancer,but the results of individual studies are inconclusive or controversial.To derive a more precise estimation of the relationship,we performed an updated meta-analysis from 31 studies based on 27 publications.Methods：A comprehensive search was conducted to examine all the eligible studies of CYP17 polymorphism and prostate cancer risk.We used odds ratios（ORs）with 95%confidence intervals（CIs）to assess the strength of the association.Results：Overall,individuals with CC/CT genotype were not associated with prostate cancer risk （CC vs.TT：OR=1.03,95%CI=0.86-1.24,P=0.72,P heterogeneity 〈0.0001;CT vs.TT：OR=0.99,95%CI=0.87- 1.12,P=0.88,P heterogeneity =0.0006）.In the stratified analysis by ethnicity,there was a significantly increased risk of prostate cancer among individuals of African descent under the recessive model（OR=1.56,95%CI=1.01- 2.39,P=0.04,P heterogeneity =0.65）.Conclusion：This meta-analysis suggested that CYP17 polymorphism might be associated with prostate cancer risk among individuals of African descent.     

Efficacy and safety of first-line chemotherapy plus bevacizumab in patients with metastatic colorectal cancer: a meta-analysis

Background What benefits and toxicities patients acquire from the use of bevacizumab combined with first-line chemotherapy remains controversial.This study was performed to evaluate the efficacy and safety of first-line chemotherapy plus bevacizumab in patients with metastatic colorectal cancer （mCRC）.Methods Several databases,including PubMed,Embase,and Cochrane Library,were searched up to April 30,2013.Eligible studies were only randomized,controlled trials （RCTs） with a direct comparison between mCRC patients treated with and without bevacizumab.Overall risk ratio （RR）,hazard ratio （HR）,odds ratio （OR）,and 95％ confidence intervals （CO were calculated employing fixed or random-effects models depending on the heterogeneity of the included trials.Results Six RCTs,including 1582 patients in chemotherapy plus bevacizumab group and 1484 patients in chemotherapyalone group,were included.Overall,the addition of bevacizumab to first-line chemotherapy increased overall response rate （ORR） by 4.5％,prolonged both progression-free survival （PFS） and overall survival （OS）,and increased the rate of total Grades 3 or 4 adverse events （G3/4AEs） by 6.9％.Significant differences were found in ORR （RR=1.22 （95％ CI 1.01-1.46）,P=0.03）,PFS （HR=0.60 （95％ Cl 0.47-0.77）,P ＜0.0001）,OS （HR=0.83 （95％ Cl 0.70-0.97）,P=0.02）,and any G3/4AEs （OR=1.56 （95％ Cl 1.29-1.89）,P ＜0.00001）.Conclusion Bevacizumab is a valuable addition to the current first-line chemotherapy regimens used in patients with mCRC,because of conferring a significant improvement in ORR,PFS,and OS,even though it increased adverse events.     

Association between folate intake, serum folate levels and the risk of lung cancer: a systematic review and meta-analysis

Background Folate plays a critical role in nucleotide synthesis and DNA methylation,and was considered to be associated with anti-carcinogenesis.Results from studies that concern the relationship between the folate intake or serum folate levels and lung cancer risk showed no consistency,which requires our further comprehensive metaanalysis.Methods Systematic literature search was conducted to identify the relevant studies (published prior to February 2013)according to standard protocol.Estimated effects were calculated under both random-effects and fixed-effects models.Heterogeneity between studies and publication bias were also evaluated.Results A total of 4390 cases and 6138 controls from 6 case-control studies revealed a significant overall inverse association between folate intake and lung cancer risk (OR =0.74,95％ Cl =0.65-0.84,P＜ 0.001).Summary of 1438 cases and 2582 controls from 4 case-control studies and 44 cases out of a cohort of 1988 participants suggested a marginal association without significance (OR =0.78,95％ Cl =0.60-1.02,P =0.075) between high serum folate levels and less lung cancer susceptibility; however,subgroup analysis about population-based case-control studies showed that high serum folate levels significantly associated with the reduced lung cancer risk (OR =0.76,95％ Cl =0.58-1.00,P =0.048).Conclusion Higher folate intake can be a protective factor against lung cancer risk,and higher serum folate level is probably associated with reduced lung cancer risk in marginal manner,though more studies are warranted to confirm these associations.     

胃肠道恶性肿瘤中胸苷酸合成酶基因多态性与5-FU化疗敏感性的Meta分析

目的 探讨胃肠道恶性肿瘤患者中胸苷酸合成酶(thymidylate synthase,TS)基因5’-端非翻译区域(5′-untranslated region,5′-UTR)多态性与以5-氟尿嘧啶(5-fluorouracil,5-FU)为基础的化疗敏感性的关系.方法 应用Meta分析随机效应模型对胃肠道恶性肿瘤患者的胸苷酸合成酶基因多态性与5-FU化疗敏感性的文献进行综合定量评价,运用REVMAN5.0进行统计学处理.结果 共入选4篇英文文献,3篇中文文献,483例患者,其中5′-UTR串联重复序列2R/2R、2R/3R基因型279例,化疗有效者122例,合并有效率43.7％,3R/3R基因型204例,化疗有效者71例,合并有效率34.8％,异质性检验显示,I2=72.0％,P=0.001,采用随机效应模型分析,OR为1.87,95％可信区间0.81～4.28,在亚组分析中,亚洲人群、高加索人群、胃癌人群、结直肠癌人群中的OR值分别为4.10(95％ CI:2.19～7.68)、0.75(95％ CI:0.26～2.15)、6.80( 95％ CI:2.33～19.86)、1.09(95％CI:0.38～3.08).结论 胃肠道恶性肿瘤中胸苷酸合成酶基因5｀UTR串联重复序列多态性与5-FU化疗敏感性无明显关系,在亚组分析时发现,亚洲人群和胃癌人群中2R/2R、2R/3R基因型化疗敏感性高于3R/3R基因型.     

Serum hyaluronan levels in oral cancer patients

Background Hyaluronan （HA） is most likely associated with tumor invasion and metastasis. Studies have shown that HA levels are often increased in serum of patients with various malignant tumors. The purpose of this study was to determine the levels of serum hyaluronan in patients with oral cancer and evaluate the value of serum HA in adjuvant diagnosis, staging and monitoring treatment response in these patients.
Methods Eighty-four hospitalized patients with oral cancer, 65 patients with benign tumors in the oral and maxillofacial region and 67 healthy individuals were included in this investigation. Venous blood was collected from these patients and the healthy individuals before therapy. One week after therapy, venous blood was collected once again in 43 patients with oral cancer. Serum samples were obtained and serum HA levels examined.
Results The serum HA concentration was significantly higher in oral cancer patients than in patients with benign tumors and in healthy controls （P〈0.05）. The serum HA level in patients with stages Ⅲ and Ⅳdisease was higher than in patients with stages Ⅰ and Ⅱ disease, but there was no significant difference in the HA level between stages Ⅰ and Ⅱnor between stages Ⅲand Ⅳ（P〉0.05）. After a complete treatment the HA levels in patients with oral cancer became lower than before treatment, but the difference was not significant （P〉0.05）.
Conclusions The results of this study suggest that the determination of HA levels may provide additional information in diagnosis of oral cancer, but its usefulness as an adjunct in clinical staging and in monitoring treatment response was limited.