Remodeling the immune microenvironment for gastric cancer therapy through antagonism of prostaglandin E2 receptor 4.

Gastric cancer is highly prevalent among digestive tract tumors. Due to the intricate nature of the gastric cancer immune microenvironment, there is currently no effective treatment available for advanced gastric cancer. However, there is promising potential for immunotherapy targeting the prostaglandin E2 receptor subtype 4 (EP4) in gastric cancer. In our previous study, we identified a novel small molecule EP4 receptor antagonist called YY001. Treatment with YY001 alone demonstrated a significant reduction in gastric cancer growth and inhibited tumor metastasis to the lungs in a mouse model. Furthermore, administration of YY001 stimulated a robust immune response within the tumor microenvironment, characterized by increased infiltration of antigen-presenting cells, T cells, and M1 macrophages. Additionally, our research revealed that YY001 exhibited remarkable synergistic effects when combined with the PD-1 antibody and the clinically targeted drug apatinib, rather than fluorouracil. These findings suggest that YY001 holds great promise as a potential therapeutic strategy for gastric cancer, whether used as a standalone treatment or in combination with other drugs.

Response of COVID-19 vaccination in multiple sclerosis patients following disease-modifying therapies: A meta-analysis.

BACKGROUND: COVID-19 vaccination is recommended for patients with multiple sclerosis (pwMS), while disease-modifying therapies (DMTs) may influence the efficacy of SARS-CoV-2 vaccines in this population. Thus, we conducted a meta-analysis to evaluate the impact of DMTs on immune response to COVID-19 vaccines in pwMS. METHODS: Literature search from December 1, 2019 to March 31, 2022 was performed in PubMed, MedRxiv, Embase and Cochrane Library. The risk of impaired response to vaccination in pwMS receiving DMTs was estimated in odds ratios (ORs) using random-effects method. FINDINGS: A total of 48 studies comprising 6860 pwMS were included. Overall, pwMS with anti-CD20 (OR=0.02, 95% CI: 0.01-0.03) and sphingosine-1-phosphate receptor modulator (S1PRM) (OR=0.03, 95% CI: 0.01-0.06) treatments had attenuated serologic response after full vaccination compared with those without DMTs. Additionally, pwMS vaccinated within six months since last anti-CD20 therapy were at significantly higher risk of blunted response compared with those receiving anti-CD20 therapy more than six months prior to vaccination (P = 0.001). We found no significant associations between other treatments (including IFN-ß, GA, DMF, TERI, NTZ, CLAD, and ALE) and humoral response to SARS-CoV-2 vaccines in pwMS. As for T-cell response, no significant difference was found between pwMS on anti-CD20 and those without DMTs after vaccination, while S1PRM was marginally associated with impaired cellular response (P = 0.03). INTERPRETATION: Our findings suggested that routine serological monitoring may be required for pwMS on anti-CD20 and S1PRMs after SARS-CoV-2 vaccination and highlighted the benefits of a booster dose. The effect of cellular response and optimal interval from last anti-CD20 treatment to vaccination should be further addressed. FUNDING: This study was supported by Natural Science Foundation of Shanghai (21ZR1433000).

Impaired serological response to COVID-19 vaccination following anticancer therapy: A systematic review and meta-analysis.

Owing to the high coronavirus disease 2019 (COVID-19)-related morbidity and fatality rate among patients with cancer, the introduction of COVID-19 vaccines is of profound significance in this fragile population. Accumulating data suggested that oncologic patients, especially those with anticancer therapy have an impaired immune response to COVID-19 vaccination. However, the exact effect of anticancer treatments on postvaccination response has not been elucidated yet. We, therefore, conducted a meta-analysis to evaluate the impact of treatments on response to COVID-19 vaccination in patients with cancer. A total of 39 studies were finally included comprising 11 075 oncologic patients. Overall, we found the humoral response was significantly decreased in patients undergoing anticancer treatments (odds ratio [OR] = 2.55, 95% confidence interval [CI]: 2.04-3.18) compared with those without active treatment. The seroconversion rates were significantly lower in patients with chemotherapy (OR = 3.04, 95% CI: 2.28-4.05), targeted therapy (OR = 4.72, 95% CI: 3.18-7.01) and steroid usage (OR = 2.19, 95% CI: 1.57-3.07), while there was no significant association between immunotherapy or hormonal therapy and seroconversion after vaccination. Subgroup analyses showed therapies with anti-CD20 antibody (OR = 11.28, 95% CI: 6.40-19.90), B-cell lymphoma 2 inhibitor (OR = 5.76, 95% CI: 3.64-9.10), and Bruton tyrosine kinase inhibitor (OR = 6.86, 95% CI: 4.23-11.15) were significantly correlated with the risk of negative humoral response to vaccination. In conclusion, our results demonstrated that specific oncologic therapies may significantly affect serological response to COVID-19 vaccines in patients with cancer. Thus, an adapted vaccination strategy taking the influence of active treatment into account is in need, and further research on the effect of the third dose of vaccine and the role of postvaccination cellular response in oncologic patients is also needed.

Immune response to vaccination against SARS-CoV-2 in hematopoietic stem cell transplantation and CAR T-cell therapy recipients.

Recipients after hematopoietic stem cell transplantation (HSCT) or chimeric antigen receptor T-cell (CAR-T) therapy are at increased risk for unfavorable outcomes after SARS-CoV-2 infection. The efficacy of COVID-19 vaccines remains undetermined in this vulnerable population, we therefore conducted a pooled analysis to evaluate the immune response after vaccination. A total of 46 studies were finally included, comprising 4757 HSCT and 174 CAR-T recipients. Our results indicated that HSCT and CAR-T recipients had an attenuated immune response to SARS-CoV-2 vaccination compared with healthy individuals, while time interval between transplant and vaccination, immunosuppressive therapy (IST) and lymphocyte counts at vaccination significantly affected the humoral response in HSCT recipients. In addition, seroconversion was significantly higher in patients with BCMA-based CAR-T than those with CD19-based CAR-T. Thus, an adapted vaccination strategy for HSCT and CAR-T recipients may be required, and further research on the effect of a booster dose of COVID-19 vaccine and the role of cellular response after vaccination is warranted.

In vitro fertilization outcomes in women with polycystic ovary syndrome: A meta-analysis.

OBJECTIVE: During the past three decades, applying IVF for infertility treatment PCOS women has increased significantly, and the landscape of treatment strategies has changed dramatically. However, early review of IVF on PCOS have insufficiently accounted for efficacy and safety of the technic. With abundant studies in recent years, there is a need to reconcile these new data. MATERIAL AND METHODS: To compare reproductive and obstetric outcomes of IVF between women with and without PCOS, a meta-analysis of 95 studies involving more than 21289 PCOS patients and 43036 controls was performed. RESULTS: Despite longer stimulation duration (WMD = 0.34 day, 95 % CI: 0.09, 0.59) and lower dose of Gn required (WMD = -361.3 IU, 95 % CI: -442.3, -280.4), more oocytes (WMD = 3.67, 95 % CI: 3.14-4.21) and matured oocytes (WMD = 2.16, 95 % CI: 1.52-2.80) per cycle were obtained from PCOS women. There were no statistically significant differences for cleavage, high-grade embryo and implantation rate. Although similar pregnancy and live birth rates per cycle were achieved in PCOS and non-PCOS women after IVF, women with PCOS still suffered from significantly increased risks of miscarriage (OR = 1.44, 95 % CI: 1.20-1.72), biochemical pregnancy loss (OR = 1.89, 95 % CI: 1.48-2.41), and OHSS (OR = 3.58, 95 % CI: 2.86-4.48), in addition to lower fertilization rate (OR = 0.79, 95 % CI: 0.71-0.88). Adverse obstetric outcomes including ectopics pregnancy and multiple pregnancies are comparable between two groups. The overall cycle cancellation rate was significantly higher among PCOS women with OR of 2.55 (95 % CI: 1.67-3.89), and concern over OHSS or hyper-response constitute the main cause. Similar results were also observed after stratified analysis. CONCLUSIONS: Our results support the effectiveness of IVF for infertility treatment among PCOS patients. However, options to minimize adverse outcomes regarding to lower fertilization, miscarriage, biochemical pregnancy loss and OHSS are required. Further studies elucidating detailed mechanism underlying these adverse outcomes could be of great importance to improve the experience of IVF treatment.

Quantitative assessment of SARS-CoV-2 RNAemia and outcome in patients with coronavirus disease 2019.

The disease spectrum of coronavirus disease 2019 (COVID-19) varies from asymptomatic infection to critical illness and death. Identification of prognostic markers is vital for predicting progression and clinical practice. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA, known as RNAemia, has been detected in the blood. However, the potential clinical value of SARS-CoV-2 RNAemia remains unknown. We, therefore, conducted a meta-analysis using a random-effects model to estimate the pooled prevalence of SARS-CoV-2 RNAemia as well as summary strength of RNAemia in association with disease severity and unfavorable clinical outcomes. A total of 21 studies involving 2181 patients were included. SARS-CoV-2 RNAemia in COVID-19 patients varied from 9.4% to 74.1%, with a pooled estimate of 34% (95% confidene interval [CI]: 26%-43%). Overall, SARS-CoV-2 RNAemia was associated with COVID-19 severity with odds ratio (OR) of 5.43 (95% CI: 3.46-8.53). In addition, SARS-CoV-2 RNAemia was a significant risk factor for unfavorable clinical outcomes (OR = 6.54, 95% CI: 3.82-11.21). The summary OR was 4.28 (95% CI: 2.20-8.33) for intensive care unit (ICU) admission, 11.07 (95% CI: 5.60-21.88) for mortality. Furthermore, RNAemia was also a significant risk factor for invasive mechanical ventilation and multiple organ failure. SARS-CoV-2 RNAemia is associated with disease severity, ICU admission, death in COVID-19, and may serve as a clinical predictor. More prospective trials in evaluating the potential of SARS-CoV-2 RNAemia as a prognostic indicator are necessary.

A non-linear dose-response relation of female body mass index and in vitro fertilization outcomes.

PURPOSE: Obesity, measured by body mass index (BMI), is implicated in adverse pregnancy outcomes for women seeking in vitro fertilization (IVF) care. However, the shape of the dose-response relationship between BMI and IVF outcomes remains unclear. METHODS: We therefore conducted a dose-response meta-analysis using a random effects model to estimate summary relative risk (RR) for clinical pregnancy (CPR), live birth (LBR), and miscarriage risk (MR) after IVF. RESULTS: A total of 18 cohort-based studies involving 975,889 cycles were included. For each 5-unit increase in BMI, the summary RR was 0.95 (95% CI: 0.94-0.97) for CPR, 0.93 (95% CI: 0.92-0.95) for LBR, and 1.09 (95% CI: 1.05-1.12) for MR. There was evidence of a non-linear association between BMI and CPR (Pnon-linearity < 10-5) with CPR decreasing sharply among obese women (BMI > 30). Non-linear dose-response meta-analysis showed a relatively flat curve over a broad range of BMI from 16 to 30 for LBR (Pnon-linearity = 0.0009). In addition, we observed a J-shaped association between BMI and MR (Pnon-linearity = 0.006) with the lowest miscarriage risk observed with a BMI of 22-25. CONCLUSIONS: In conclusion, obesity contributed to increased risk of adverse IVF outcomes in a non-linear dose-response manner. More prospective trials in evaluating the effect of body weight control are necessary.

Effects of occupational exposure to noise and dust on blood pressure in Chinese industrial workers.

Along with the rapid development of economy and urbanization, noise and air pollution are becoming major occupational health hazards in the process of industrial production. In this study, we collected data from 7293 industrial workers in China. The association between occupational exposure of noise and dust and blood pressure was investigated. Controlling for demographic variables, including sex, age, and length of service, a stepwise regression model with backward elimination was constructed. The results showed that both noise and dust decreased the level of systolic blood pressure (p < 0.001). This finding prompted the manufacturing industry to reduce noise and dust hazards and protect the occupational health of workers. Prospective studies in different populations are still required to verify the net contribution of noise and dust to the decrease in blood pressure.

Quantitative assessment of maternal biomarkers related to one-carbon metabolism and neural tube defects.

Periconceptional supplementation with folic acid reduces the occurrence of neural tube defects (NTDs). The association between maternal abnormalities in homocysteine metabolism (e.g., hyperhomocysteinaemia, folate deficiency and low vitamin B12) and the risk of NTDs-affected pregnancies has been widely evaluated in recent years, although the results are conflicting. To investigate this inconsistency, we performed a meta-analysis of 32 studies, involving 1,890 NTD-affected mothers and 3,995 control mothers, to develop an understanding of the relationship between maternal biomarkers related to one-carbon metabolism and NTD. A random-effects model was used to calculate the ratio of means (RoM) between the cases and controls, along with the 95% confidence intervals (CIs). A significant increase in homocysteine levels was observed in NTD-affected mothers compared with controls (RoM: 1.16, 95% CI: 1.09-1.23, P = 1.8 × 10(-6)). The pooled analysis also revealed that NTD-affected mothers had significantly lower levels of folate (RoM: 0.93, 95% CI: 0.88-0.97, P = 0.002), vitamin B12 (RoM: 0.91, 95% CI: 0.87-0.95, P = 3.6 × 10(-5)) and red blood cell folate (RoM: 0.92, 95% CI: 0.86-0.98, P = 0.01). Therefore, altered plasma levels of biomarkers related to one-carbon metabolism are associated with NTD-affected pregnancies.

Label-free quantitative proteomic analysis reveals dysfunction of complement pathway in peripheral blood of schizophrenia patients: evidence for the immune hypothesis of schizophrenia.

Schizophrenia is a complex mental disease caused by a combination of serial alterations in genetic and environmental factors. Although the brain is usually considered as the most relevant organ in schizophrenia, accumulated evidence suggests that peripheral tissues also contribute to this disease. In particular, abnormalities of the immune system have been identified in the peripheral blood of schizophrenia patients. To screen the serum proteomic signature of schizophrenia patients, we conducted shotgun proteomic analysis on serum samples of schizophrenia patients and healthy controls. High-abundance proteins were eliminated by immunoaffinity before LC-MS/MS analysis. The multivariate statistical test partial least squares-discriminant analysis (PLS-DA) was applied to build models for screening out variable importance in the projection (VIP) and 27 proteins were identified as being responsible for discriminating between the proteomic profiles of schizophrenia patients and healthy controls. Pathway analysis based on these 27 proteins revealed that complement and coagulation cascades was the most significant pathway. ELISA-based activity analyses indicated that the alternative complement pathway was suppressed in schizophrenia patients. Ingenuity pathways analysis was used to conduct the interaction network of 27 proteins. The network exhibited common features such as, nervous system development and function, humoral immune response and inflammatory response, and highlighted some proteins with important roles in the immune system, such as hub nodes. Our findings indicate dysregulation of the alternative complement pathway in schizophrenia patients. The protein interaction network enhances the interpretation of proteomic data and provides evidence that the immune system may contribute to schizophrenia.

Dynamic network of transcription and pathway crosstalk to reveal molecular mechanism of MGd-treated human lung cancer cells.

Recent research has revealed various molecular markers in lung cancer. However, the organizational principles underlying their genetic regulatory networks still await investigation. Here we performed Network Component Analysis (NCA) and Pathway Crosstalk Analysis (PCA) to construct a regulatory network in human lung cancer (A549) cells which were treated with 50 uM motexafin gadolinium (MGd), a metal cation-containing chemotherapeutic drug for 4, 12, and 24 hours. We identified a set of key TFs, known target genes for these TFs, and signaling pathways involved in regulatory networks. Our work showed that putative interactions between these TFs (such as ESR1/Sp1, E2F1/Sp1, c-MYC-ESR, Smad3/c-Myc, and NFKB1/RELA), between TFs and their target genes (such as BMP41/Est1, TSC2/Myc, APE1/Sp1/p53, RARA/HOXA1, and SP1/USF2), and between signaling pathways (such as PPAR signaling pathway and Adipocytokines signaling pathway). These results will provide insights into the regulatory mechanism of MGd-treated human lung cancer cells.

Genetic polymorphisms in CYP2E1: association with schizophrenia susceptibility and risperidone response in the Chinese Han population.

BACKGROUND: CYP2E1 is a member of the cytochrome P450 superfamily, which is involved in the metabolism and activation of both endobiotics and xenobiotics. The genetic polymorphisms of CYP2E1 gene (Chromosome 10q26.3, Accession Number NC_000010.10) are reported to be related to the development of several mental diseases and to be involved in the clinical efficacy of some psychiatric medications. We investigated the possible association of CYP2E1 polymorphisms with susceptibility to schizophrenia in the Chinese Han Population as well as the relationship with response to risperidone in schizophrenia patients. METHODS: In a case-control study, we identified 11 polymorphisms in the 5' flanking region of CYP2E1 in 228 schizophrenia patients and 384 healthy controls of Chinese Han origin. From among the cases, we chose 130 patients who had undergone 8 weeks of risperidone monotherapy to examine the relationship between their response to risperidone and CYP2E1 polymorphisms. Clinical efficacy was assessed using the Brief Psychiatric Rating Scale (BPRS). RESULTS: Statistically significant differences in allele or genotype frequencies were found between cases and controls at rs8192766 (genotype p = 0.0048, permutation p = 0.0483) and rs2070673 (allele: p = 0.0018, permutation p = 0.0199, OR = 1.4528 95%CI = 1.1487-1.8374; genotype: p = 0.0020, permutation p = 0.0225). In addition, a GTCAC haplotype containing 5 SNPs (rs3813867, rs2031920, rs2031921, rs3813870 and rs2031922) was observed to be significantly associated with schizophrenia (p = 7.47E-12, permutation p<0.0001). However, no association was found between CYP2E1 polymorphisms/haplotypes and risperidone response. CONCLUSIONS: Our results suggest that CYP2E1 may be a potential risk gene for schizophrenia in the Chinese Han population. However, polymorphisms of the CYP2E1 gene may not contribute significantly to individual differences in the therapeutic efficacy of risperidone. Further studies in larger groups are warranted to confirm our results.

Quantitative assessment of the effect of LRRK2 exonic variants on the risk of Parkinson's disease: a meta-analysis.

Leucine-rich repeat kinase 2 (LRRK2, PARK8) gene has attracted considerable attention since the variants in this gene are recognized as the most common cause of Parkinson's disease (PD) so far. A number of association studies concerning variants of LRRK2 gene and PD susceptibility have been conducted in various populations. However, some results were inconclusive. To derive a more precise estimation of the relationship between LRRK2 and genetic risk of PD, we performed a comprehensive meta-analysis which included 27,363 cases and 29,741 controls from 61 published case-control studies. Totally, the effect of five LRRK2 variants all within the coding regions, i.e. G2019S, G2385R, R1628P, P755L and A419V, were evaluated in the meta-analysis using fixed effect model or random effects model if heterogeneity existed. There were genetic associations between four variants (G2019S, G2385R, R1628P and A419V) and increased PD risk, while there was no evidence of statistically significant association between P755L and PD. Publication bias and heterogeneity were absent in most analyses. Within its limitations, this meta-analysis demonstrated that the G2019S, G2385R, R1628P and A419V variations are risk factors associated with increased PD susceptibility. However, these associations vary in different ethnicities.

NMDA receptor hypofunction induces dysfunctions of energy metabolism and semaphorin signaling in rats: a synaptic proteome study.

There is considerable evidence to suggest that aberrations of synapse connectivity contribute to the pathophysiology of schizophrenia and that N-methyl-D-aspartate (NMDA) receptor-mediated glutamate transmission is especially important. Administration of MK-801 ([+]-5-methyl-10, 11-dihydro-5H-dibenzo-[a, d]-cycloheptene-5, 10-iminehydrogenmaleate) induces hypofunction of NMDA receptors in rats, which are widely used as a model for schizophrenia. We investigated synaptosomal proteome expression profiling of the cerebral cortex of MK-801-treated Sprague-Dawley rats using the 2-dimensional difference gel electrophoresis method, and 49 differentially expression proteins were successfully identified using Matrix-Assisted Laser Desorption/Ionization Time-of-Flight/Time-of-Flight mass spectrometry. We carried out a literature search for further confirmation of subsynaptic locations and to explore the relevance to the diseases of differentially expressed proteins. Ingenuity Pathways Analysis (IPA) was used to further examine the underlying relationship between the changed proteins. The network encompassing "cell morphology, cell-to-cell signaling and interaction, nervous system development and function" was found to be significantly altered in the MK-801-treated rats. "Energy metabolism" and "semaphorin signaling in neurons" are the most significant IPA canonical pathways to be affected by MK-801 treatment. Using western blots, we confirmed the differential expression of Camk2a, Crmp2, Crmp5, Dnm1, and Ndufs3 in both synaptosome proteins and total proteins in the cerebral cortex of the rats. Our study identified the change and/or response of the central nervous transmission system under the stress of NMDA hypofunction, underlining the importance of the synaptic function in schizophrenia.

Quantitative assessment of the effect of ABCA1 R219K polymorphism on the risk of coronary heart disease.

In the past decade, a number of case-control studies have been conducted to investigate the relationship between the ATP-binding cassette transporter A1 (ABCA1) R219K polymorphism and coronary heart disease (CHD). However, the results have been inconclusive. The purpose of the present study is to investigate whether this polymorphism confers significant susceptibility to CHD using a meta-analysis. PubMed, Embase and CNKI database were searched to get the genetic association studies. Then data were extracted. Pooled odds ratio (OR) and 95% confidence interval (CI) were calculated. Moreover, subgroup and sensitive analysis were performed. In total, 9,437 cases and 16,270 controls were involved in the meta-analysis. The K219 was significantly associated with CHD (OR = 0.80, 95% CI 0.69-0.92, P(Z) = 0.001). However, significant heterogeneity was present. Further subgroup analysis suggested ethnicity explained much heterogeneity. In Asians, K219 showed a strong protective effect and the pooled OR was 0.69 (95% CI 0.55-0.86 P(Z) = 0.0009). While in Caucasians the result was not significant (OR = 0.87, 95% CI 0.73-1.04, P(Z) = 0.12). In conclusion, our results indicate that the ABCA1 R219K polymorphism is a protective factor of CHD in Asians, but not in Caucasians.

Genetic diversity of the apolipoprotein E gene and diabetic nephropathy: a meta-analysis.

In the past decade, a number of case-control studies have been carried out to investigate the relationship between the ApoE polymorphism and diabetic nephropathy. However, the results have been inconclusive. To investigate this inconsistency, we performed a meta-analysis of all available studies dealing with the relationship between the ApoE polymorphism and DN. The 23 studies in the meta- analysis included 6,012 diabetic patients with (n = 2,979) and without (n = 3,033) DN. The ApoE ε2 allele was significantly associated with DN (OR = 1.64, 95% CI: 1.26-2.13; P(Z) = 0.00027), whereas the ε4 allele was non-significantly associated with DN (OR = 0.93, 95% CI: 0.78-1.11; P(Z) = 0.418). However, significant heterogeneity was detected. In further subgroup analyses, genotyping methods, outcome of cases and duration of diabetes in controls were found to explain some of the heterogeneity. Genotypic analysis also found a strong association between the ε2 carriers and DN (OR = 1.61, 95% CI: 1.22-2.13; P(Z) = 0.001) and indicated that ε4 tended to have a marginally significant protective effect for DN (OR = 0.82, 95% CI: 0.65-1.03; P(Z) = 0.085). The results of our meta-analysis support a genetic association between the ApoE polymorphism and DN. ε2 increases the risk of DN in diabetes patients, while ε4 trends to be protective. These findings may have implications for therapeutic intervention in diabetic nephropathy.

The PstI/RsaI and DraI polymorphisms of CYP2E1 and head and neck cancer risk: a meta-analysis based on 21 case-control studies.

BACKGROUND: CYP2E1 encodes a member of the cytochrome P450 superfamily of enzymes which play a central role in activating and detoxifying many carcinogens and endogenous compounds thought to be involved in the development of cancer. The PstI/RsaI and DraI polymorphism are two of the most commonly studied polymorphisms of the gene for their association with risk of head and neck cancer, but the results are conflicting. METHODS: We performed a meta-analysis using 21 eligible case-control studies with a total of 4,951 patients and 6,071 controls to summarize the data on the association between the CYP2E1 PstI/RsaI and DraI polymorphism and head and neck cancer risk, especially by interacting with smoking or alcohol. RESULTS: Compared with the wild genotype, the OR was 1.96 (95% CI: 1.33-2.90) for PstI/RsaI and 1.56 (95% CI: 1.06-2.27) for DraI polymorphism respectively. When stratified according to ethnicity, the OR increased in the Asians for both polymorphisms (OR = 2.04, 95% CI: 1.32-3.15 for PstI/RsaI; OR = 2.04, 95% CI: 1.27-3.29 for DraI), suggesting that the risk is more pronounced in Asians. CONCLUSION: Our meta-analysis suggests that individuals with the homozygote genotypes of PstI/RsaI or DraI polymorphism might be associated with an increased risk of head and neck cancer, especially in Asians.

Genetic polymorphism analysis of cytochrome P4502E1 (CYP2E1) in Chinese Han populations from four different geographic areas of Mainland China.

CYP2E1 is one of a superfamily of enzymes that play a central role in activating and detoxifying many xenobiotics and endogenous compounds thought to be involved in the development of several human diseases. Among other factors, individual susceptibility to developing these pathologies relies on genetic polymorphisms, which are related to ethnic differences, since the frequency of mutant genotypes varies in different populations. The aim of this study was to investigate the genetic basis of CYP2E1 polymorphisms in the populations of four different geographical locations of China. Twenty-two different CYP2E1 polymorphisms, including six novel variants in promoter regions and a novel nonsense mutation, were identified. The frequencies of some polymorphisms and genotypes demonstrated significant differences among the four populations. Linkage disequilibrium analysis and tag SNP selection were performed. Haplotypes were analyzed within the selected tag SNPs. Tag SNP selection and haplotype distributions showed differences across the four populations.