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OBJECTIVE: Published evidence indicated that the leptin receptor (LEPR) gene polymorphisms are associated with polycystic ovary syndrome (PCOS) risk. However, studies on the association between the polymorphisms of LEPR gene are inconsistent or even controversial. MATERIAL AND METHODS: We conducted this meta-analysis to explore the more precise relationship between LEPR polymorphisms and PCOS risk. Relevant articles were searched with five online databases up to March 1 2023. Odds ratios (OR) with 95% confidence intervals (CI) were selected to examine the statistical strength of each genetic model. Moreover, RNA secondary structure and variant effects of these loci were examined with in silico analysis. RESULTS: Overall, 11 publications were analyzed, and the pooled results did not present any significant association between rs1137101 A/G polymorphism and PCOS risk in general population and some subgroup analysis. But the significant association were observed in Asian population (AG vs. AA: OR = 0.51, 95%CI = 0.32-0.81, p = .01, I2=0%; AG + GG vs. AA: OR = 0.41, 95%CI = 0.26-0.65, p < .01, I2=25.9%). Moreover, similar positive associations were also observed in rs1805096 polymorphism with PCOS risk. CONCLUSION: In summary, our meta-analysis suggested that the LEPR gene polymorphisms might be associated with PCOS susceptibility. Owing to the limited studies and small sample size in our meta-analysis, more well-designed studies from different races were needed to be conducted to verify the current results.
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Síndrome del Ovario Poliquístico , Receptores de Leptina , Femenino , Humanos , Pueblo Asiatico , Predisposición Genética a la Enfermedad , Síndrome del Ovario Poliquístico/genética , Polimorfismo de Nucleótido Simple , Receptores de Leptina/genéticaRESUMEN
Evidence suggests that there is a close association between myeloperoxidase (MPO) gene rs2333227 G>A polymorphism with Alzheimer's disease (AD) susceptibility. We conducted a meta-analysis to explore the precise association between MPO rs2333227 G>A polymorphism and AD susceptibility. Online databases were searched and the relevant information was collected. Crudeodds ratios with 95% confidence intervals were calculated. Trial sequential analysis (TSA), heterogeneity analyses, accumulative analyses, sensitivity analyses, and publication biasestests were performed. Overall, nine publications (ten independent case-controls) were included in this meta-analysis, involving 3260 participants. Pooled results revealed no significant association between MPO rs2333227 G>A polymorphism and AD susceptibility was observed. TSA showed that the present meta-analysis remained inconclusive due to insufficient evidence. In summary, the current meta-analysis indicated that the MPO rs2333227 G>A polymorphism may not be acausalfactor in the development of AD.
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Enfermedad de Alzheimer/genética , Peroxidasa/genética , Predisposición Genética a la Enfermedad , Humanos , RiesgoRESUMEN
BACKGROUND: Aldehyde dehydrogenase-2 (ALDH2) plays an important role in the alcohol detoxification and acetaldehyde metabolism. Published studies have demonstrated some inconsistent associations between ALDH2 rs671 G>A polymorphism and head and neck cancer (HNC) risk. METHODS: A meta-analysis was performed to provide pooled data on the association between the ALDH2 rs671 G>A polymorphism and HNC risk. Electronic databases were searched to identify relevant studies. Odds ratios and 95% confidence intervals (CIs) were used to examine the pooled effect size of each genetic model. In addition, heterogeneity test, accumulative analysis, sensitivity analysis, and publication bias were conducted to test the statistical power. RESULTS: Thirteen publications (14 independent case-control studies) involving 10,939 subjects were selected. The stratified analysis indicated that both light/moderated drinking (e.g., GA vs. GG: OR = 1.47, 95% CI = 1.16 to 1.86, p < 0.01, I2 = 81.1%) and heavy drinking would increase HNC risk with rs671 G>A mutation (e.g., GA vs. GG: OR = 2.30, 95% CI = 1.11 to 4.77, p = 0.03, I2 = 81.9%). CONCLUSIONS: In summary, this meta-analysis suggested that the ALDH2 rs671 G>A polymorphism may play an important synergistic effect in the pathogenesis of HNC development in East Asians.
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Aldehído Deshidrogenasa Mitocondrial/genética , Pueblo Asiatico/genética , Predisposición Genética a la Enfermedad/genética , Neoplasias de Cabeza y Cuello/genética , Polimorfismo de Nucleótido Simple/genética , Estudios de Casos y Controles , Asia Oriental/epidemiología , Predisposición Genética a la Enfermedad/epidemiología , Neoplasias de Cabeza y Cuello/diagnóstico , Neoplasias de Cabeza y Cuello/epidemiología , HumanosRESUMEN
Rec ent studies have suggested a closer association between angiotensin-converting enzyme (ACE) gene polymorphisms and polycystic ovary syndrome (PCOS) risk, but the results were inconsistent. We conducted this meta-analysis to explore the precise associations between ACE gene I/D polymorphism and PCOS risk. Online electronic databases (PubMed, Embase, SCI index, CNKI, and Wanfang) were searched. Odds ratios (ORs) with 95% confidence interval (CIs) were calculated to assess the association between ACE gene I/D polymorphism and PCOS risk. In addition, heterogeneity, accumulative/sensitivity analysis, and publication bias were conducted to check the statistical power. Overall, 12 published case-control studies with 2248 patients and 1759 controls were included according to the criteria. Significant increased risk was found for PCOS susceptibility with I/D mutation (D vs. I: OR = 1.62, 95%CI = 1.24-2.11, P < 0.01, I2 = 86.1%; DD vs. II: OR = 2.10, 95%CI = 1.35-3.27, P < 0.01, I2 = 79.8%; ID + DD vs. II: OR = 1.57, 95%CI = 1.06-2.32, P = 0.02, I2 = 79.3%; DD vs. II + ID: OR = 1.91, 95%CI = 1.39-2.65, P < 0.01, I2 = 79.1%). Furthermore, some similar associations were also observed in subgroups. In summary, the current evidences indicated that ACE gene I/D polymorphism plays an important role in PCOS development, both in Asian and Caucasian descendants.
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Angiotensinas , Síndrome del Ovario Poliquístico , Angiotensinas/genética , Femenino , Predisposición Genética a la Enfermedad , Humanos , Peptidil-Dipeptidasa A/genética , Síndrome del Ovario Poliquístico/genética , Polimorfismo GenéticoRESUMEN
BACKGROUND: Published researches have suggested some associations between PPAR-γ and ischemic stroke (IS) development. This meta-analysis was conducted to evaluate the association between PPAR-γ gene polymorphisms and IS risk. MATERIALS AND METHODS: A systematic search was conducted in PubMed, Embase, Web of Science, China National Knowledge Infrastructure, and WanFang databases. The pooled association of odd ratios (ORs) and its 95% confidence interval (CI) was calculated to assess the IS risk of PPAR-γ rs1801282 C/G and rs3856806 C/T polymorphisms. Furthermore, the heterogeneity test, cumulative analyses, sensitivity analyses, and publication bias were conducted. RESULT: Sixteen publications with 3786 cases and 5343 controls were identified. Overall findings indicated that rs1801282 C/G polymorphism may be associated with an increased risk for IS (GG vs. CC: OR = 2.17 95%CI = 1.09-4.35, p = .03, I2 = 0%; GG vs. CC+CG: OR = 2.15, 95%CI = 1.07-4.32, p = .03, I2 = 0%). The similar results were also found in the subgroup analysis. In addition, no significant association was observed between rs3856806 C/T polymorphism and IS risk. CONCLUSION: In conclusion, our study showed that PPAR-γ rs1801282 C/G polymorphism probably plays an important role in IS occurrence. The result should be verified with more studies in the future.
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Accidente Cerebrovascular Isquémico , PPAR gamma , Predisposición Genética a la Enfermedad/genética , Humanos , Oportunidad Relativa , PPAR gamma/genética , Polimorfismo de Nucleótido SimpleRESUMEN
The objective of this study is to find out the potential influence of miR-301a in an experimental cerebral ischemia-reperfusion (I/R) rat model through targeting NDRG2. Rats with cerebral I/R injury were constructed and classified into model, miR-301a inhibitor, miR-301a mimic, NC (negative control), siNDRG2, NDRG2, and miR-301a inhibitor + si-NDRG2 groups, as well as another sham group. Cerebral infarct volume and cell apoptosis were observed by TTC staining and TUNEL staining. The targeting relationship between miR-301a and NDRG2 was verified by luciferase assay. ELISA, qRT-PCR, and Western blot were used to detect the expressions of related molecules. Compared with sham group, rats in the model group had elevated neurological function score and infarct volume; meanwhile, the cell apoptosis rate and inflammatory response were also increased with enhanced expression of miR-301a and NDRG2 (all P < 0.05). These changes were worsened in the miR-301a mimic and si-NDRG2 groups. Conversely, those rats in the miR-301a inhibitor and NDRG2 groups presented increased NDRG2, and at the same time, other above concerning factors also exhibited opposite tendencies (all P < 0.05). Dual-luciferase reporter gene assay confirmed that NDRG2 was a target gene of miR-301a, and si-NDRG2 could reverse the neuroprotective effect of miR-301a inhibitor in rats with cerebral I/R injury. Inhibiting miR-301a has a neuroprotective effect on rats with cerebral I/R injury to ameliorate cell apoptosis and inflammatory response through possibly targeting NDRG2.
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Infarto de la Arteria Cerebral Media/terapia , MicroARNs/genética , Animales , Infarto de la Arteria Cerebral Media/genética , Infarto de la Arteria Cerebral Media/metabolismo , Masculino , MicroARNs/antagonistas & inhibidores , MicroARNs/metabolismo , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , Tratamiento con ARN de Interferencia/métodos , Ratas , Ratas Sprague-DawleyRESUMEN
Background: Serum pepsinogen I (PGI) concentration and PGI/PGII ratio (PGR) are often used as serological markers for gastric fundus atrophy (AGA) and gastric carcinoma. However, their diagnostic value in esophageal carcinoma (EC) is inaccurate. Methods: This study evaluated the diagnostic value of PGI and PGR in EC by searching the PubMed, Web of Science, Embase, Cochrane Library and Cochrane Central Register of Controlled Trials databases for literature on the diagnosis of EC with PGI and PGR from January 1, 2000 to October 2, 2018. The included literature were systematically evaluated using QUSDAS-2 software. Meta-analysis was conducted using STATA 15.0 software. The summary receiver operating characteristic curve (SROC) accuracy was plotted, the area under the curve was calculated. Results: A total of 84 papers were selected, and after screening, nine papers on esophageal squamous cell carcinoma (ESCC) were finally included. Results showed low an ESCC-specific diagnostic sensitivity (0.27), high specificity (0.85), and 0.63 AUC of SROC when PGI≤70 ng/mL. When PGR≤3, the ESCC-specific diagnostic sensitivity was low (0.29), the specificity was high (0.83), and the AUC of SROC was 0.63. Conclusion: According to the current research results, PGI≤70 ng/mL or PGR≤3 diagnostic ESCC sensitivity is low, and specificity is high. These findings indicate that neither PGI≤70 ng/mL nor PGR≤3 can be used as an ESCC-screening index.
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BACKGROUND: The diagnosis rate of early stage esophageal squamous cell carcinoma (ESCC) is low due to the lack of specific tumor markers. Seeking for these markers is beneficial to improve the early diagnosis rate and the prognosis of patients. This study profiles the differentially expressed proteins of early stage ESCC patients via the AAH-BLG-507 protein chip, which further consolidates the clinical evidence of ESCC diagnosis. MATERIALS AND METHODS: In this study, 20 serum samples were collected from Taihe Hospital between August 2016 and June 2017. Ten of them carried ESCC, while the rest were healthy controls. To profile the proteins' expression level, the AAH-BLG-507 protein chip was used, and both highly expressed and lowly expressed proteins were fished out. Meanwhile, their biological roles were examined by using Gene Ontology (GO) database and String database, and they were further verified by ELISA. RESULTS: Results showed that the expression levels of AXL, ARTN, Ang2, BDNF, BMP7, cripto-1, CCL28, E-selectin, IL-6, IL-8 and SHH in the serum of early ESCC were significantly upregulated (P<0.05), particularly IL-6 and IL-8. The expression levels of TSP1 and MMP-8 were markedly downregulated (P<0.05). Analysis showed that these proteins were mainly involved in angiogenesis, signal transduction, cell proliferation and migration, indicating the close relationship with the development of ESCC. CONCLUSION: It suggested that IL-6 and IL-8 proteins could be considered as the markers for ESCC diagnosis.
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Polymerase chain reaction-restriction fragments length polymorphism (PCR-RFLP) was used to explore the distribution of apolipoprotein A5 gene -1131T>C and 56C>G polymorphisms in 257 healthy Hubei Han people. The following results were calculated: the frequency of -1131TT genotype was 50.9%, far more than that of -1131TC and -1131CC genotypes (32.9% and 16.2%, respectively). The number of T allele carriers was higher than that of C carriers, and their respective frequencies were 0.675 and 0.325. There were 56GG and 56GC genotypes, but only 2 individuals in all subjects carried the G allele, the frequency of which was low than 5%. Furthermore, the frequency of genotypes and alleles in apoa5 -1131T>C and 56C>G polymorphisms was clearly different from other races and areas. We conclude that the apoa5 -1131T>C variation should be considered a single nucleotide polymorphism, but the 56C>G variation should be considered as a mutation instead.
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Apolipoproteínas A/genética , Pueblo Asiatico/genética , Etnicidad/genética , Polimorfismo Genético , Anciano , Apolipoproteína A-V , China , Femenino , Frecuencia de los Genes , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Grupos Raciales/genéticaRESUMEN
Proton pump inhibitors (PPIs) and histamine-2-receptor antagonists (H2RAs) are used for gastro-esophageal reflux disease (GERD); however, the clinical evidence for treatment is poor. We evaluated the effectiveness and tolerability of different doses of PPIs, H2RAs and placebo in adults with GERD. Six online databases were searched through September 1, 2016. All related articles were included and combined with a Bayesian network meta-analysis from randomized controlled trials (RCTs). The GRADE systems were employed to assess the main outcome. Ninety-eight RCTs were identified, which included 45,964 participants. Our analysis indicated that the full/standard dose of esomeprazole at 40 mg per day was the most efficient in healing among nine different dosages of PPIs and H2RAs. The main efficacy outcome did not change after adjustments for the area, age, level of disease from endoscopy, year of publication, pharmaceutical industry sponsorship, Intention-to-treat (ITT)/per-protocol (PP), withdrawal rate, pre-set select design bias, single blinded and unblinded studies, study origination in China, study arms that included zero events, inconsistency node or discontinued drug were accounted for in the meta-regressions and sensitivity analyses. This research suggests that the full/standard doses (40 mg per day) of esomeprazole should be recommended as first-line treatments for GERD in adults for short-term therapy.
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Reflujo Gastroesofágico/tratamiento farmacológico , Antagonistas de los Receptores Histamínicos/administración & dosificación , Inhibidores de la Bomba de Protones/administración & dosificación , China , Humanos , Metaanálisis en Red , Placebos/administración & dosificación , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del TratamientoRESUMEN
Molecular epidemiological studies have revealed a closer association between cyclin D1 (CCND1) polymorphism and the risk of colorectal cancer; however, the results were inconsistent. The aim of the present meta-analysis was to investigate the association between CCND1 G870A polymorphism and colorectal cancer risk. Online electronic databases (PubMed and Embase) were searched. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to assess the association between CCND1 G870A polymorphism and the risk of colorectal cancer. In addition, heterogeneity, publication bias and sensitivity analysis were performed to guarantee the statistical power. In total, 23 published case-control studies with 6,320 patients and 8,252 controls were selected. Significantly increased risks were observed in four genetic models (A vs. G: OR=1.09, 95% CI=1.00-1.18, I2=54.3%; GA vs. GG: OR=1.13, 95% CI=1.04-1.24, I2=18.2%; AA vs. GG, OR=1.17: 95% CI=1.00-1.38, I2=52.5%; GA+AA vs. GG: OR=1.14, 95% CI=1.05-1.24, I2=33.8%). Similarly, significant associations were also identified in the stratified analysis in the cancer subtype of sporadic colorectal cancer (GA vs. GG: OR=1.21, 95% CI=1.04-1.42, I2=24.1%; GA+AA vs. GG: OR=1.18, 95% CI=1.02-1.37, I2=35.0%), Caucasian population (GA vs. GG, OR=1.14, 95% CI=1.02-1.28, I2=19.8%; GA+AA vs. GG, OR=1.14, 95% CI=1.02-1.27, I2=37.5%) and other subgroups of control design and genotyping type. The present updated meta-analysis suggested that CCND1 G870A may present an increased risk for developing colorectal cancer, particularly in sporadic colorectal cancer and a Caucasian population.
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There are limitations to the use of single biomarker levels, for example phosphate and tensin homology (PTEN) or vascular endothelial growth factor (VEGF), in the diagnosis of esophageal squamous cell carcinoma (ESCC). The present study therefore aimed to evaluate the clinical implications of combined detection of multiple biomarkers. The associations between PTEN and VEGF expression status, microvessel density (MVD), and the pathological characteristics of 50 patients with ESCC were determined using χ2, analysis of variance, and t-tests. The results indicated that the PTEN-positive rate was negatively correlated with ESCC histological grade (P<0.01), depth of ESCC invasion (P<0.01) and lymph node metastasis status. Furthermore, the VEGF-positive rate was correlated with lymph node metastasis status, while MVD was correlated with the depth of ESCC invasion (P<0.01) and lymph node metastasis status (P<0.05). The PTEN-positive rate was negatively correlated with the VEGF-positive rate. A higher MVD was identified in ESCC samples than that of the normal esophageal mucosa, particularly in VEGF-positive ESCC specimens compared with those of VEGF-negative specimens, and PTEN-negative ESCC specimens compared with that of the PTEN-positive ESCC specimens. These results suggested that combined detection of PTEN and VEGF levels, as well as evaluation of MVD in patients with ESCC may provide essential information for improvements in the diagnosis and prognosis of ESCC.
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BACKGROUND: The association between Interleukin-17(IL-17) gene polymorphisms and Helicobacter pylori (H. pylori) infection and gastric cancer susceptibility were inconsistent. We therefore performed a comprehensive meta-analysis about all three genetic polymorphisms of IL-17 to derive a more precise estimation. METHODS: PubMed, Embase, CNKI and Wanfang databases were researched on the associations between IL-17A rs2275913G>A, rs3748067C>T and IL-17F rs763780 T>C and gastric cancer risk. Odds ratio (OR) with a 95% confidence interval (CI) was applied to assess the relationships. Publication bias, sensitivity and cumulative analysis was conducted to guarantee the strength of meta-analysis. RESULTS: Overall, eleven related studies involving 4,478 cases and 5,612 controls were collected. Significantly increased risk between IL-17A rs2275913G>A polymorphism and gastric cancer were observed (A vs. G: OR = 1.22, 95% CI = 1.08-1.37, P<0.01, I(2) = 72.3%; AA vs. GG: OR = 1.55, 95% CI = 1.21-1.99, P<0.01, I(2) = 74.3%; GA + AA vs. GG: OR = 1.19, 95% CI = 1.05-1.39, P<0.01, I(2) = 48.2%; AA vs. GG + GA: OR = 1.50, 95% CI = 1.16-1.95, P<0.01, I(2) = 81.2%). For IL-17F rs3748067C>T and rs763780 T>C polymorphisms, only few significantly increased risk could be found in genetic models. Moreover, H. pylori infection also be proved to increase the risk of gastric cancer combined with rs3748067C>T mutation. CONCLUSIONS: Our meta-analysis suggests that the three IL-17 polymorphisms were associated with a significantly increased risk of gastric cancer, especially in Chinese.
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The common functional cyclin D1 (CCND1) G870A polymorphism may influence the risk of esophageal cancer. However, the conclusions of previous studies have been inconsistent for the association between the CCND1 G870A polymorphism and esophageal cancer risk. A meta-analysis of 11 published case-control studies was performed, including 2,111 patients with esophageal cancer and 3,232 controls, to investigate the association between the CCND1 G870A polymorphism and esophageal cancer risk. The odds ratio (OR) with a 95% confidence interval (CI) was applied to assess the association between the CCND1 G870A polymorphism and esophageal cancer risk. A significant association between the CCND1 G870A polymorphism and esophageal cancer risk was observed for the allele contrast (A vs. G: OR, 1.23; 95% CI, 1.02-1.48; P=0.029), codominant (AA vs. GG: OR, 1.58; 95% CI; 1.06-2.35; P=0.024) and recessive models (AA vs. GG + GA: OR, 1.33, 95% CI, 1.03-1.73; P=0.030). However, in the stratified analysis by ethnicity, study design and pathology, there was no significant association detected in these genetic models. In conclusion, results of the meta-analysis suggested that the CCND1 G870A polymorphism is a potential risk factor in the development of esophageal cancer.
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AIM: To investigate the effect of GW4064 on the expression of adipokines and their receptors during differentiation of 3T3-L1 preadipocytes and in HepG2 cells. METHODS: The mRNA expression of farnesoid X receptor (FXR), peroxisome proliferator-activated receptor-gamma 2 (PPAR-γ2), adiponectin, leptin, resistin, adiponectin receptor 1 (AdipoR1), adiponectin receptor 2 (AdipoR2), and the long isoform of leptin receptor (OB-Rb) and protein levels of adiponectin, leptin, and resistin were determined using fluorescent real-time PCR and enzyme linked immunosorbent assay, respectively, on days 0, 2, 4, 6, and 8 during the differentiation of 3T3-L1 preadipocytes exposed to GW4064. Moreover, mRNA expression of AdipoR2 and OB-Rb was also examined using fluorescent real-time PCR at 0, 12, 24, and 48 h in HepG2 cells treated with GW4064. RESULTS: The mRNA expression of FXR, PPAR-γ2, adiponectin, leptin, resistin, AdipoR1, AdipoR2, and OB-Rb and protein levels of adiponectin, leptin, and resistin increased along with differentiation of 3T3-L1 preadipocytes (P < 0.05 for all). The mRNA expression of FXR, PPAR-γ2, adiponectin, leptin, and AdipoR2 in 3T3-L1 preadipocytes, and AdipoR2 and OB-Rb in HepG2 cells was significantly increased after treatment with GW4064, when compared with the control group (P < 0.05 for all). A similar trend was observed for protein levels of adipokines (including adiponectin, leptin and resistin). However, the expression of resistin, AdipoR1, and OB-Rb in 3T3-L1 cells did not change after treatment with GW4064. CONCLUSION: The FXR agonist through regulating, at least partially, the expression of adipokines and their receptors could offer an innovative way for counteracting the progress of metabolic diseases such as nonalcoholic fatty liver disease.
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Adipocitos/efectos de los fármacos , Adipoquinas/metabolismo , Hepatocitos/efectos de los fármacos , Isoxazoles/farmacología , Receptores Citoplasmáticos y Nucleares/agonistas , Células 3T3-L1 , Adipocitos/metabolismo , Adipoquinas/genética , Animales , Células Hep G2 , Hepatocitos/metabolismo , Humanos , Ratones , PPAR gamma/efectos de los fármacos , PPAR gamma/genética , PPAR gamma/metabolismo , ARN Mensajero/metabolismo , Receptores de Adiponectina/efectos de los fármacos , Receptores de Adiponectina/genética , Receptores de Adiponectina/metabolismo , Receptores Citoplasmáticos y Nucleares/genética , Receptores Citoplasmáticos y Nucleares/metabolismo , Receptores de Leptina/efectos de los fármacos , Receptores de Leptina/genética , Receptores de Leptina/metabolismo , Transducción de Señal/efectos de los fármacos , Factores de Tiempo , Regulación hacia ArribaRESUMEN
AIM: To study the relation between CYP1A1 Ile462Val polymorphism and colorectal cancer risk by meta-analysis. METHODS: A meta-analysis was performed to investigate the relation between CYP1A1 Ile462Val polymorphism and colorectal cancer risk by reviewing the related studies until September 2010. Data were extracted and analyzed. Crude odds ratio (OR) with 95% confidence interval (CI) was used to assess the strength of relation between CYP1A1 Ile462Val polymorphism and colorectal cancer risk. RESULTS: Thirteen published case-control studies including 5336 cases and 6226 controls were acquired. The pooled OR with 95% CI indicated that CYP1A1 Ile462Val polymorphism was significantly related with colorectal cancer risk (Val/Val vs Ile/Ile: OR = 1.47, 95% CI: 1.16-1.86, P = 0.002; dominant model: OR = 1.33, 95% CI: 1.01-1.75, P = 0.04; recessive model: OR = 1.49, 95% CI: 1.18-1.88, P = 0.0009). Subgroup ethnicity analysis showed that CYP1A1 Ile462Val polymorphism was also significantly related with colorectal cancer risk in Europeans (Ile/Val vs Ile/Ile: OR = 1.22, 95% CI: 1.05-1.42, P = 0.008; dominant model: OR = 1.24, 95% CI: 1.07-1.43, P = 0.004) and Asians (Val/Val vs Ile/Ile: OR = 1.40, 95% CI: 1.07-1.82, P = 0.01; recessive model: OR = 1.46, 95% CI: 1.12-1.89, P = 0.005). CONCLUSION: CYP1A1 Ile462Val may be an increased risk factor for colorectal cancer.