Global Burden of Thyroid Cancer From 1990 to 2017

IMPORTANCE

Thyroid cancer is the most pervasive endocrine cancer worldwide. Studies examining the association between thyroid cancer and country, sex, age, sociodemographic index (SDI), and other factors are lacking.

OBJECTIVE

To examine the thyroid cancer burden and variation trends at the global, regional, and national levels using data on sex, age, and SDI.

DESIGN, SETTING, AND PARTICIPANTS

In this cross-sectional study, epidemiologic data were gathered using the Global Health Data Exchange query tool, covering persons of all ages with thyroid cancer in 195 countries and 21 regions from January 1, 1990, to December 31, 2017; data analysis was completed on October 1, 2019. All participants met the Global Burden of Disease Study inclusion criteria.

MAIN OUTCOMES AND MEASURES

Outcomes included incidence, deaths, and disability-adjusted life-years (DALYs) of thyroid cancer. Measures were stratified by sex, region, country, age, and SDI. The estimated annual percentage changes (EAPCs) and age-standardized rates were calculated to evaluate the temporal trends.

RESULTS

Increases of thyroid cancer were noted in incident cases (169%), deaths (87%), and DALYs (75%). Age-standardized incidence rate (ASIR) showed an upward trend over time, with an EAPC of 1.59 (95% CI, 1.51-1.67); decreases were noted in EAPCs of age-standardized death rate (-0.15; 95% CI, -0.19 to -0.12) and age-standardized DALY rate (-0.11; 95% CI, -0.15 to -0.08). Almost half (41.73% for incidence, 50.92% for deaths, and 54.39% for DALYs) of the thyroid cancer burden was noted in Southern and Eastern Asia. In addition, females accounted for most of the thyroid cancer burden (70.22% for incidence, 58.39% for deaths, and 58.68% for DALYs) and increased by years in this population, although the ASIR of males with thyroid cancer (EAPC, 2.18; 95% CI, 2.07-2.28) increased faster than that of females (EAPC, 1.38; 95% CI, 1.30-1.46). A third (34%) of patients with thyroid cancer resided in countries with a high SDI, and most patients were aged 50 to 69 years, which was older than the age in other quintiles (high SDI quintile compared with all other quintiles, P<.05). The most common age at onset of thyroid cancer worldwide was 15 to 49 years in female individuals compared with 50 to 69 years in male individuals (P<.05). Death from thyroid cancer was concentrated in participants aged 70 years or older and increased by years (average annual percentage change, 0.10; 95% CI, 0.01-0.21; P<.05). Furthermore, people in lower SDI quintiles developed thyroid cancer and died from it earlier than those in other quintiles (high and high-middle SDI vs low and low-middle SDI, P<.05).

CONCLUSIONS AND RELEVANCE

Data from this study suggest considerable heterogeneity in the epidemiologic patterns of thyroid cancer across sex, age, SDI, region, and country, providing information for governments that may help improve national and local cancer control policies.

Distinct role of the Fas rs1800682 and FasL rs763110 polymorphisms in determining the risk of breast cancer among Han Chinese females

Background

In recent years, studies have demonstrated that polymorphisms in the promoters of Fas and FasL are significantly associated with breast cancer risk. However, the results of these studies were inconsistent. This case–control study was performed to explore the associations between Fas rs1800682 and FasL rs763110 polymorphisms and breast cancer.

Materials and methods

A hospital-based case–control study of 560 Han Chinese females with breast cancer (583 controls) was conducted. The MassARRAY system was used to search for a possible association between the disease risk and the two single nucleotide polymorphisms, Fas rs1800682 and FasL rs763110. Statistical analyses were performed using SNPStats software to conduct Pearson’s chi-square tests in five different genetic models. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated after adjustment to age and body mass index. PHASE v2.1 software was used to reconstruct all common haplotypes.

Results

A statistically significant association was found between Fas rs1800682 and increased breast cancer risk (AG vs AA: OR =1.37, 95% CI =1.06–1.78; AA+AG vs GG: OR =1.32, 95% CI =1.04–1.66), and also it was found that the FasL rs763110 polymorphism may decrease the risk. Stratified analyses demonstrated that the rs763110 polymorphism was associated with lower breast cancer risk among postmenopausal females (heterozygote model: OR =0.69, 95% CI =0.49–0.97; dominant model: OR =0.70, 95% CI =0.51–0.96). The T allele of rs763110 was also associated with a decreased risk of lymph node metastasis (allele model: OR =0.75, 95% CI =0.57–0.97) and an increased risk of the breast cancer being human epidermal growth factor receptor 2 positive (allele model: OR =1.37, 95% CI =1.03–1.18). Moreover, haplotype analysis showed that A_rs1800682T_rs763110 was associated to a statistically significant degree with lower risk of breast cancer (OR =0.70, 95% CI =0.53–0.91).

Conclusion

These data suggest that the presence of Fas rs1800683 is an important risk factor for breast cancer, whereas FasL rs763110 may exert a protective effect against the onset of breast cancer.

Wnt1 and SFRP1 as potential prognostic factors and therapeutic targets in cutaneous squamous cell carcinoma

The Wnt signaling pathway plays a key role in insurgence and progression of many different forms of cancer. Some crucial components of the Wnt pathway have been proposed to be novel targets for cancer therapy. To date, the Wnt signaling pathway has not been studied in cutaneous squamous cell carcinoma (CSCC). This study was designed to investigate the expression of Wnt1 and SFRP1 from the Wnt pathway in CSCC. Tissue samples were obtained from 35 patients with CSCC and 30 controls admitted to the Xinjiang Uygur Autonomous Region People's Hospital at Urumchi City, China. Gene and protein expressions of Wnt1 and SFRP1 were quantified by immunohistochemistry and western blotting. Wnt1 expression was significantly higher (P < 0.05) in CSCC samples than in normal skin cells of the control subjects; in contrast, SFRP1 expression was significantly lower in CSCC tissues than that in tissues of control subjects (P < 0.05). Moreover, Wnt1 expression (P < 0.05) was found to be correlated with histopathological differentiation in CSCC, and negatively correlated with SFRP1 expression in CSCC (rs = -0.473, P = 0.015). Therefore, we concluded that Wnt1 and SFRP1 play important roles in the development of CSCC and could be potent markers for diagnosis, prevention, and therapy of CSCC.

PD-1 rs2227982 Polymorphism Is Associated With the Decreased Risk of Breast Cancer in Northwest Chinese Women: A Hospital-Based Observational Study

Programmed death-1 (PD-1) is crucial in cancer and is well characterized as a negative T-cell regulator that functions by delivering inhibitory signals. We aimed to evaluate the relationship between PD-1 polymorphisms (rs10204525, rs2227982, and rs7421861) and breast cancer risk.We selected 560 breast cancer patients and 583 age-, sex-, and ethnicity-matched healthy controls from Northwest China. The PD-1 polymorphisms were genotyped by using Sequenom MassARRAY. Associations were estimated with odds ratios (ORs) and 95% confidence intervals (95% CIs).For the rs10204525 and rs7421861 polymorphisms, no differences in breast cancer risk were found in any of the genetic models. For the rs2227982 polymorphism, the variant genotypes were significantly associated with decreased breast cancer risk (CT vs CC: OR = 0.68, 95% CI = 0.52-0.91; CT + TT vs CC: OR = 0.69, 95% CI = 0.53-0.90). In analyses stratified by age, the decreased risk was observed among the younger subjects (OR = 0.68, 95% CI = 0.47-0.97). We found that the decreased risk observed for the variant genotypes of rs2227982 was associated with the Her-2 status (CT vs CC: OR = 0.55, 95% CI = 0.37-0.84; CT + TT vs CC: OR = 0.56, 95% CI = 0.38-0.82). The haplotype analysis showed that the Ars10204525 Trs2227982 Crs7421861 haplotype was associated with a significantly decreased risk of breast cancer (OR = 0.50, 95% CI = 0.34-0.75).Our findings support an association between the PD-1 rs2227982 polymorphism and decreased breast cancer risk, especially in Her-2 positive breast cancer patients in the Chinese population.

Genetic variation in WDR1 is associated with gout risk and gout-related metabolic indices in the Han Chinese population

Gout is the most common form of inflammatory arthritis affecting men, and current evidence suggests that genetic factors contribute to its progression. As a previous study identified that WD40 repeat protein 1 (WDR1) is associated with gout in populations of European descent, we sought to investigate its relationship with this disease in the Han Chinese population. We genotyped six WDR1 single nucleotide polymorphisms in 143 gout cases and 310 controls using Sequenom MassARRAY technology. The SPSS 16.0 software was used to perform statistical analyses. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated by unconditional logistic regression, with adjustments for age and gender. In an analysis using an allelic model, we identified that the minor alleles of rs3756230 (OR = 0.64, 95%CI = 0.450-0.911, P = 0.013) and rs12498927 (OR = 1.377, 95%CI = 1.037-1.831, P = 0.027) were associated with gout risk. In addition, we found that the "A/A" genotype of rs12498927 was associated with increased risk of gout under codominant (OR = 2.22, 95%CI = 1.12- 4.40, P = 0.042) and recessive models (OR = 2.24, 95%CI = 1.20-4.17, P = 0.012). We also determined the "A/G" genotype of rs12498927 to be significantly associated with higher urea levels in gout patients (P = 0.017). Our data shed new light on the association between genetic variations in the WDR1 gene and gout susceptibility in the Han Chinese population.

PDK2 and ABCG2 genes polymorphisms are correlated with blood glucose levels and uric acid in Tibetan gout patients

Previous studies have shown that the PDK2 and ABCG2 genes play important roles in many aspects of gout development in European populations. However, a detailed genotype-phenotype analysis was not performed. The aim of the present study was to investigate the potential association between variants in these two genes and metabolism-related quantitative phenotypes relevant to gout in a Chinese Tibetan population. In total, 316 Chinese Tibetan gout patients were recruited from rheumatology outpatient clinics and 6 single nucleotide polymorphisms in PDK2 and ABCG2 were genotyped, which were possible etiologic variants as identified in the HapMap Chinese Han Beijing population. A significant difference in blood glucose levels was detected between different genotypes of rs2728109 (P = 0.005) in the PDK2 gene. We also detected a significant difference in the mean serum uric levels between different genotypes of rs3114018 (P = 0.004) in the ABCG2 gene. All P values remained significant after Bonferroni's correction for multiple testing. Our data demonstrate potential roles for PDK2 and ABCG2 polymorphisms in the metabolic phenotypes of Tibetan gout patients, which may provide new insights into the etiology of gout. Further studies are required to confirm these findings.

Genetic Variation in Metastasis-Associated in Colon Cancer-1 and the Risk of Breast Cancer Among the Chinese Han Population: A STROBE-Compliant Observational Study

Metastasis-associated in colon cancer-1 (MACC1), a newly identified oncogene, is involved in angiogenesis, invasiveness, and metastasis in many cancers. Epidemiological studies have indicated the associations between MACC1 polymorphisms and cancer risk. However, the association between genetic polymorphisms in MACC1 and breast cancer (BC) was not clear. This study aimed to evaluate the relationship between MACC1 polymorphisms and BC risk.We genotyped 4 single-nucleotide polymorphisms (SNPs) in MACC1 (rs975263, rs1990172, rs3735615, rs4721888) to determine the haplotypes in 560 BC patients and 583 age-, sex-, and ethnicity-matched healthy individuals. Genotypes were determined using the Sequenom MassARRAY method. We estimated the odds ratios (ORs) and 95% confidence intervals (95% CIs) using the chi-square test.There were significant differences between patients and controls in the MACC1 rs975263 allelic (T vs C: OR = 0.76, 95% CI = 0.61-0.95, P = 0.014) and genotypic groups (TC vs TT: OR = 0.70, 95% CI = 0.54-0.92, P = 0.009; TC+CC vs TT: OR = 0.71, 95% CI = 0.55-0.92, P = 0.008). Analysis of clinical features demonstrated significant associations between rs975263 and Scarff-Bloom-Richardson (SBR) grade 3 cancer (P = 0.006) and postmenopausal women (P = 0.018). Compared with the rs4721888 CC genotype, the frequency of rs4721888 GC and GC+CC variants was higher in patients. Further analysis revealed that the variant genotypes were positively associated with lymph node metastasis. However, we failed to find any relationships between rs1990172 or rs3735615 polymorphism and BC risk. In addition, haplotype analysis indicated that the CTGG and CTCG haplotypes (rs975263, rs1990172, rs3735615, rs4721888) were significantly associated with decreased susceptibility to BC (P = 0.029 and 0.019 respectively).Our results suggest that rs975263 and rs4721888 polymorphisms in MACC1 are associated with the risk of BC susceptibility and may be involved in the progression of BC in Chinese women.

Association Between Single Nucleotide Polymorphisms in DNA Polymerase Kappa Gene and Breast Cancer Risk in Chinese Han Population: A STROBE-Compliant Observational Study

DNA polymerases are responsible for ensuring stability of the genome and avoiding genotoxicity caused by a variety of factors during DNA replication. Consequently, these proteins have been associated with an increased cancer risk. DNA polymerase kappa (POLK) is a specialized DNA polymerase involved in translesion DNA synthesis (TLS) that allows DNA synthesis over the damaged DNA. Recently, some studies investigated relationships between POLK polymorphisms and cancer risk, but the role of POLK genetic variants in breast cancer (BC) remains to be defined. In this study, we aimed to evaluate the effects of POLK polymorphisms on BC risk.We used the Sequenom MassARRAY method to genotype 3 single nucleotide polymorphisms (SNPs) in POLK (rs3213801, rs10077427, and rs5744533), in order to determine the genotypes of 560 BC patients and 583 controls. The association of genotypes and BC was assessed by computing the odds ratio (OR) and 95% confidence intervals (95% CIs) from logistic regression analyses.We found a statistically significant difference between patient and control groups in the POLK rs10077427 genotypic groups, excluding the recessive model. A positive correlation was also found between positive progesterone receptor (PR) status, higher Ki67 index, and rs10077427 polymorphism. For rs5744533 polymorphism, the codominant, dominant, and allele models frequencies were significantly higher in BC patients compared to healthy controls. Furthermore, our results indicated that rs5744533 SNP has a protective role in the postmenopausal women. However, we failed to find any associations between rs3213801 polymorphism and susceptibility to BC.Our results indicate that POLK polymorphisms may influence the risk of developing BC, and, because of this, may serve as a prognostic biomarker among Chinese women.

Association between a functional genetic polymorphism (rs2230199) and age-related macular degeneration risk: a meta-analysis

The association between the rs2230199 C>G single nucleotide polymorphism (SNP) in complement component 3 and age-related macular degeneration (AMD) risk has been examined extensively but the results are not consistent among studies. The aim of this study was to perform a meta-analysis of all available studies on this SNP in relation to AMD. The comprehensive databases of PubMed, Medline, Web of Knowledge, CNKI, and Google Scholar were searched for case-control studies investigating the association between the rs2230199 polymorphism and AMD susceptibility. ORs with 95%CIs were estimated to assess the association. Sensitivity analysis, test of heterogeneity, cumulative meta-analysis, and assessment of bias were also performed. A total of 15 published studies including 5593 cases and 5181 controls were used in this meta-analysis. Overall, the rs2230299 SNP was significantly associated with the risk of AMD in the overall population under the additive model (OR = 1.571, 95%CI = 1.414-1.745, P = 0.000), dominant model (OR = 1.681, 95%CI = 1.521-1.858, P = 0.000), and allelic model (OR = 1.597, 95%CI = 1.470-1.734, P = 0.000). In the subgroup analysis by ethnicity, the same results were found in Caucasian populations, while no significant correlations were found in Asian populations for all comparison models. In conclusion, our meta-analysis provides evidence that the rs2230199 polymorphism contributes to the development of AMD. Further large-scale multicenter epidemiological studies are warranted to confirm this finding.

Genetic polymorphisms in very important pharmacogenomic (VIP) variants in the Tibetan population

Genetic polymorphisms of very important pharmacogenomic (VIP) variants are important for personalized medicine. However, these have not been extensively studied in the Tibetan population. In this study, 82 VIP variants were detected in the Tibetan and Han (HAN) populations from northwestern China. Subsequently, we compared the differences between the Tibetan population and ten populations, including the HAN, Japanese in Tokyo (JPT), Mexican ancestry in Los Angeles (MEX), Toscans in Italy (TSI), African ancestry in Southwest USA (ASW), Luhya in California Webuye, Kenya (LWK), Gujarati Indians in Houston, Texas (GIH), Maasai in Kinyawa, Kenya (MKK), Yoruba in Ibadan, Nigeria (YRI), and Utah residents with Northern and Western European ancestry from the CEPH collection (CEU). Using the χ(2) test, we identified differences in the frequency distribution of 4, 4, 7, 10, 11, 11, 13, 15, 19, and 20 loci in the Tibetan population, compared to the HAN, JPT, MEX, TSI, ASW, LWK, GIH, MKK, YRI, and CEU populations, respectively [P < 0.05/(82*10)]. rs2115819, rs9934438, and rs689466, located in the ALOX5 (arachidonate 5-lipoxygenase), VKORC1 (vitamin K epoxide reductase complex, subunit 1) and PTGS2 (prostaglandin-endoperoxide synthase 2) genes, respectively, in the Tibetan population were different from those in most of the populations. Our results complement the information provided by the database of pharmacogenomics on Tibetan people, and provide an avenue for personalized treatment in the Tibetan population.

CHRNA5 polymorphisms and risk of lung cancer in Chinese Han smokers

Lung cancer is the most frequent cancer among men in many countries. It is the result of interactions between genetic and environmental factors, among which tobacco smoking is a key environmental factor. CHRNA5, Cholinergic Receptor, Neuronal Nicotinic, Alpha Polypeptide-5, was previously reported to be associated with lung cancer risk. To identify the genetic susceptibility and tobacco smoking that influence lung cancer risk in Han population, we performed a case-control study in 228 patients and 301 controls. These data were compared using the χ(2)-test, genetic model analysis, and haplotype analysis. rs495956, rs680244, rs601079, rs555018, 588765 and rs11637635 showed an increased risk of lung cancer in both allelic model and genetic mode analysis. The genotype G/A-A/A of rs11637635 was most strongly associated with a 2.17-fold increased risk of lung cancer in dominant model (p = 0.018). One SNP, rs684513, was associated with a 0.645-fold decreased risk (p = 0.033) in allelic model analysis. By haplotype association analysis, haplotype sequences CTTATCAAAGA and GA of CHRNA5 were found to be associated with a 2.03-fold and 1.91-fold increased lung cancer risk (p < 0.05). Our results, combined with those from previous studies, suggest that genetic variation in CHRNA5 may influence susceptibility to lung cancer among Han smokers.

The RTEL1 rs6010620 polymorphism and glioma risk: a meta-analysis based on 12 case-control studies

BACKGROUND

The association between the RTEL1 rs6010620 single nucleotide polymorphism (SNP) and glioma risk has been extensively studied. However, the results remain inconclusive. To further examine this association, we performed a meta-analysis.

MATERIALS AND METHODS

A computerized search of the PubMed and Embase databases for publications regarding the RTEL1 rs6010620 polymorphism and glioma cancer risk was performed. Genotype data were analyzed in a meta-analysis. Odds ratios (ORs) with 95% confidence intervals (CIs) were estimated to assess the association. Sensitivity analyses, tests of heterogeneity, cumulative meta-analyses, and assessments of bias were performed in our meta-analysis.

RESULTS

Our meta-analysis confirmed that risk with allele A is lower than with allele G for glioma. The A allele of rs6010620 in RTEL1 decreased the risk of developing glioma in the 12 case-control studies for all genetic models: the allele model (OR=0.752, 95%CI: 0.715-0.792), the dominant model (OR=0.729, 95%CI: 0.685-0.776), the recessive model (OR=0.647, 95%CI: 0.569-0.734), the homozygote comparison (OR=0.528, 95%CI: 0.456-0.612), and the heterozygote comparison (OR=0.761, 95%CI: 0.713-0.812).

CONCLUSIONS

In all genetic models, the association between the RTEL1 rs6010620 polymorphism and glioma risk was significant. This meta-analysis suggests that the RTEL1 rs6010620 polymorphism may be a risk factor for glioma. Further functional studies evaluating this polymorphism and glioma risk are warranted.

SLC2A9 and ZNF518B polymorphisms correlate with gout-related metabolic indices in Chinese Tibetan populations

Current evidence suggests that heredity and metabolic syndrome contribute to gout progression. SLC2A9 and ZNF518B may play a role in gout progression in different populations, but no studies have focused on the Tibetan Chinese population. In this study, we determined whether variations in these 2 genes were correlated with gout-related indices in Chinese-Tibetan gout patients. We detected 6 single nucleotide polymorphisms in SLC2A9 and ZNF518B in 319 Chinese Tibetan gout patients. One-way analysis of variance was used to evaluate the polymorphisms' effects on gout based on mean serum levels of metabolism indicators. Polymorphisms in SLC2A9 and ZNF518B affected multiple risk factors related to gout development. Significant differences in serum triglyceride levels and high-density lipoprotein-cholesterol level were detected between different genotypic groups with SLC2A9 polymorphisms rs13129697 (P = 0.022), rs4447863 (P = 0.018), and rs1014290 (P = 0.045). Similarly in ZNF518B, rs3217 (P = 0.016) and rs10016022 (P = 0.046) were associated with high creatinine and glucose levels, respectively. This study is the first to investigate and identify positive correlations between SLC2A9 and ZNF518B gene polymorphisms and metabolic indices in Tibetan gout patients. We found significant evidence indicating that genetic polymorphisms affect gout-related factors in Chinese Tibetan populations.

Association of colorectal cancer susceptibility variants with esophageal cancer in a Chinese population

AIM: To investigate the association between colorectal cancer (CRC) genetic susceptibility variants and esophageal cancer in a Chinese Han population.

METHODS: A case-control study was conducted including 360 esophageal cancer patients and 310 healthy controls. Thirty-one single-nucleotide polymorphisms (SNPs) associated with CRC risk from previous genome-wide association studies were analyzed. SNPs were genotyped using Sequenom Mass-ARRAY technology, and genotypic frequencies in controls were tested for departure from Hardy-Weinberg equilibrium using a Fisher’s exact test. The allelic frequencies were compared between cases and controls using a χ² test. Associations between the SNPs and the risk of esophageal cancer were tested using various genetic models (codominant, dominant, recessive, overdominant, and additive). ORs and 95%CIs were calculated by unconditional logistic regression with adjustments for age and sex.

RESULTS: The minor alleles of rs1321311 and rs4444235 were associated with a 1.53-fold (95%CI: 1.15-2.06; P = 0.004) and 1.28-fold (95%CI: 1.03-1.60; P = 0.028) increased risk of esophageal cancer in the allelic model analysis, respectively. In the genetic model analysis, the C/C genotype of rs3802842 was associated with a reduced risk of esophageal cancer in the codominant model (OR = 0.52, 95%CI: 0.31-0.88; P = 0.033) and recessive model (OR = 0.55, 95%CI: 0.34-0.87; P = 0.010). The rs4939827 C/T-T/T genotype was associated with a 0.67-fold (95%CI: 0.46-0.98; P = 0.038) decreased esophageal cancer risk under the dominant model. In addition, rs6687758, rs1321311, and rs4444235 were associated with an increased risk. In particular, the T/T genotype of rs1321311 was associated with an 8.06-fold (95%CI: 1.96-33.07; P = 0.004) increased risk in the codominant model.

CONCLUSION: These results provide evidence that known genetic variants associated with CRC risk confer risk for esophageal cancer, and may bring risk for other digestive system tumors.

Meta-analysis of the association between the rs8034191 polymorphism in AGPHD1 and lung cancer risk

BACKGROUND

Possible associations between the single nucleotide polymorphism (SNP) rs8034191 in the aminoglycosidephosphotransferase domain containing 1 (AGPHD1) gene and lung cancer risk have been studied by many researchers but the results have been contradictory.

MATERIALS AND METHODS

A computerized search for publications on rs8034191 and lung cancer risk was performed. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to assess the association between rs8034191 and lung cancer risk with 13 selected case-control studies. Sensitivity analysis, test of heterogeneity, cumulative meta-analysis, and assessment of bias were also performed.

RESULTS

A significant association between rs8034191 and lung cancer susceptibility was found using the dominant genetic model (OR=1.344, 95% CI: 1.285-1.406), the additive genetic model (OR=1.613, 95% CI: 1.503-1.730), and the recessive genetic model (OR=1.408, 95% CI: 1.319-1.503). Moreover, an increased lung cancer risk was found with all genetic models after stratification of ethnicity.

CONCLUSIONS

The association between rs8034191 and lung cancer risk was significant using multiple genetic models, suggesting that rs8034191 is a risk factor for lung cancer. Further functional studies of this polymorphism and lung cancer risk are warranted.

Genetic variations in the CLNK gene and ZNF518B gene are associated with gout in case-control sample sets

A genome-wide association study of gout in European populations identified 12 genetic variants strongly associated with risk of gout, but it is unknown whether these variants are also associated with gout risk in Chinese populations. A total of 145 patients with gout and 310 healthy control patients were recruited for a case-control association study. Twelve SNPs of CLNK and ZNF518B gene were genotyped, and association analysis was performed. Odds ratios (ORs) with 95 % confidence intervals (CIs) were used to assess the association. Overall, we found four risk alleles for gout in patients: the allele "G" of rs2041215 and rs1686947 in the CLNK gene by dominant model (OR 1.66; 95 % CI 1.04-2.63; p = 0.031) (OR 2.19; 95 % CI 1.38-3.46; p = 0.001) and additive model (OR 1.39; 95 % CI 1.00-1.93; p = 0.049) (OR 1.67; 95 % CI 1.19-2.32; p = 0.003), respectively, and the allele "A" of rs10938799 and rs10016022 in ZNF518B gene by recessive model (OR 4.66; 95 % CI 1.44-15.09; p = 0.008) (OR 4.54; 95 % CI 1.23-16.76; p = 0.020). Further haplotype analysis showed that the TCATTCTGA haplotype of CLNK was more frequent among patients with gout (adjusted OR 0.48; 95 % CI 0.24-0.95; p = 0.036). Additionally, polymorphisms of rs2041215, rs10938799, and rs17467273 were also correlated with clinical pathological parameters. This study provides evidence for gout susceptibility genes, CLNK and ZNF518B, in a Chinese population, which may have potential as diagnostic and prognostic marker for gout patients.

CCDC26 gene polymorphism and glioblastoma risk in the Han Chinese population

BACKGROUND

Glioblastoma (GBM) is an immunosuppressive tumor whose median survival time is only 12- 15 months, and patients with GBM have a uniformly poor prognosis. It is known that heredity contributes to formation of glioma, but there are few genetic studies concerning GBM.

MATERIALS AND METHODS

We genotyped six tagging SNPs (tSNP) in Han Chinese GBM and control patients. We used Microsoft Excel and SPSS 16.0 statistical package for statistical analysis and SNP Stats to test for associations between certain tSNPs and risk of GBM in five different models. ORs and 95%CIs were calculated for unconditional logistic-regression analysis with adjustment for age and gender. The SHEsis software platform was applied for analysis of linkage disequilibrium, haplotype construction, and genetic associations at polymorphism loci.

RESULTS

We found rs891835 in CCDC26 to be associated with GBM susceptibility at a level of p=0.009. The following genotypes of rs891835 were found to be associated with GBM risk in four different models of gene action: i) genotype GT (OR=2.26; 95%CI, 1.29-3.97; p=0.019) or GG (OR=1.33; 95%CI, 0.23-7.81; p=0.019) in the codominant model; ii) genotypes GT and GG (OR=2.18; 95%CI, 1.26-3.78; p=0.0061) in the dominant model; iii) GT (OR=2.24; 95%CI, 1.28-3.92; p=0.0053) in the overdominant model; iv) the allele G of rs891835 (OR=1.85; 95%CI, 1.14-3.00; p=0.015) in the additive model. In addition, "CG" and "CGGAG" were found by haplotype analysis to be associated with increased GBM risk. In contrast, genotype GG of CCDC26 rs6470745 was associated with decreased GBM risk (OR=0.34; 95%CI, 0.12-1.01; p=0.029) in the recessive model.

CONCLUSIONS

Our results, combined with those from previous studies, suggest a potential genetic contribution of CCDC26 to GBM progression among Han Chinese.

Mitochondrial DNA levels in blood and tissue samples from breast cancer patients of different stages

AIMS

Alterations in mitochondrial DNA (mtDNA) have been implicated in carcinogenesis and tumor progression. We here evaluated the diagnostic and prognostic potential of mtDNA as a biomarker for breast cancer.

METHODS

Using multiplex real-time polymerase chain reaction, nuclear DNA (nDNA) and mtDNA levels in serum, buffy coat, tumor, and tumor-adjacent tissue samples from 50 breast cancer patients were determined and assessed for associations with clinicopathological features. To evaluate mtDNA as a biomarker for distinguishing between the four sample types, we created receiver operating characteristic (ROC) curves.

RESULTS

The mtDNA levels in buffy coat were significantly lower than in other sample types. Relative to tumor-adjacent tissue, reduced levels of mtDNA were identified in buffy coat and tumor tissue but not in serum. According to ROC curve analysis, mtDNA levels could be used to distinguish between buffy coat and tumor-adjacent tissue samples with good sensitivity (77%) and specificity (83%). Moreover, mtDNA levels in serum and tumor tissue were positively associated with cancer TMN stage.

CONCLUSIONS

The mtDNA levels in blood samples may represent a promising, non-invasive biomarker in breast cancer patients. Additional, large-scale validation studies are required to establish the potential use of mtDNA levels in the early diagnosis and monitoring of breast cancer.

Genetic association of CHEK2, GSTP1, and ERCC1 with glioblastoma in the Han Chinese population

Glioblastoma (GBM), a deadly brain tumor, is the most malignant glioma. It mainly occurs in adults and occurs significantly more in males than in females. We genotyped 19 tag single nucleotide polymorphisms (tSNPs) from 13 genes in a case-control study of the Han Chinese population to identify genetic factors contributing to the risk of GBM. These tSNPs were genotyped by Sequenom MassARRAY RS1000. Statistical analysis was performed using χ(2) test and SNPStats, a website software. Using χ(2) test, we found that the distribution of two tSNPs (rs2267130 in checkpoint kinase 2 (CHEK2), p = 0.040; rs1695 in GSTP1, p = 0.023) allelic frequencies had significant difference between cases and controls. When we analyzed all of the tSNPs using the SNPStats software, we found that rs1695 in GSTP1 decreased the risk of GBM in log-additive model (OR = 0.56, 95% CI, 0.34-0.94, p = 0.022). Besides, we found that there is an interaction between rs3212986 in excision repair cross-complementing group 1 (ERCC1) and gender under codominant and recessive models. The gene polymorphisms in CHEK2, GSTP1, and ERCC1 may be involved in GBM in the Han Chinese population. Since our sample size is small, further investigation needs to be performed.

RTEL1 and TERT polymorphisms are associated with astrocytoma risk in the Chinese Han population

Common variants of multiple genes play a role in glioma onset. However, research related to astrocytoma, the most common primary brain neoplasm, is rare. In this study, we chose 21 tagging SNPs (tSNPs), previously reported to be associated with glioma risk in a Chinese case-control study from Xi'an, China, and identified their contributions to astrocytoma susceptibility. We found an association with astrocytoma susceptibility for two tSNPs (rs6010620 and rs2853676) in two different genes: regulator of telomere elongation helicase 1 (RTEL1) and telomerase reverse transcriptase (TERT), respectively. We confirmed our results using recessive, dominant, and additive models. In the recessive model, we found two tSNPs (rs2297440 and rs6010620) associated with increased astrocytoma risk. In the dominant model, we found that rs2853676 was associated with increased astrocytoma risk. In the additive model, all three tSNPs (rs2297440, rs2853676, and rs6010620) were associated with increased astrocytoma risk. Our results demonstrate, for the first time, the potential roles of RTEL1 and TERT in astrocytoma development.

Ophthalmic findings in a family with early-onset isolated ectopia lentis and the p.Arg62Cys mutation of the fibrillin-1 gene (FBN1)

PURPOSE

The purpose of this paper is to describe ophthalmic findings in a family with isolated ectopia lentis (EL) caused by a specific FBN1 mutation.

METHODS

Detailed family histories and clinical data were recorded for six isolated EL patients of 11 family members. The ophthalmological and systematic examinations were performed on patients and unaffected members of the investigated family. The detailed ocular examinations included visual acuity, anterior chamber depth, pupil size, lens location, optometry, central corneal thickness, keratometry, slitlamp examination, fundus examination, axial length, ocular B-ultrasound, gonioscope checking, ultrasound biomicroscopy (UBM) and intraocular pressure (IOP; Goldmann applanation tonometer). Systematic examinations included the measurement of echocardiogram, height, arm span, skull, face, jaw, tooth, breast bone, spinal column, and skin. Genomic DNA was extracted using the phenol-chloroform extraction method for all subjects, and sequencing was carried out on an ABI Prism 3730 Genetic Analyzer.

RESULTS

A heterozygous mutation, c.184C>T (p.Arg62Cys) in exon 2 of FBN1 was identified in all affected members but was not found in any unaffected member of the family. Our study presented detailed clinical manifestations, including some novel ophthalmic findings, such as pupillary abnormality, different types of glaucoma, and progressive hyperopia.

CONCLUSIONS

Ophthalmic findings and the p.Arg62Cys mutation of FBN1 gene were reported in a family with early-onset isolated ectopia lentis.

Selected polymorphisms of GSTP1 and TERT were associated with glioma risk in Han Chinese

BACKGROUND

Current evidence suggests that a majority of the inherited risks play a major role in glioma susceptibility, and glioma is due to the co-inheritance of multiple low-risk variants. These variants can be identified through association studies including such as genome-wide association studies (GWAS), which has led the glioma epidemiology researchers to focus on identifying potential disease-causing factors.

METHODS

We evaluated and validated 10 tag single nucleotide polymorphisms (tSNPs) in seven genes associated with glioma susceptibility in a Han Chinese population, including 301 glioma cases and 302 controls, using a multiplexed single nucleotide polymorphism (SNP) MassEXTEND assay. We ascertained the genotypic frequencies for each tSNP in control subjects were within Hardy-Weinberg equilibrium (HWE) using an exact test, and then compared the genotype and allele frequencies of glioma patients and control subjects using the χ2 test. We then applied three genetic models (dominant, recessive, and additive) using PLINK software to assess the association of each tSNP with glioma risk.

RESULTS

We identified two tSNPs to be associated with glioma susceptibility (rs1695, GSTP1, P = 0.019; rs2853676, TERT, P = 0.039), which we confirmed using dominant and additive model analyses. The genotype &ldquo;GA&rdquo; for rs1695 was recognized to be a protective genotype for glioma (OR, 0.67; 95% CI, 0.47-0.96; P = 0.027), while the genotype &ldquo;AG&rdquo; for rs2853676 was shown to be a risk genotype for glioma (OR, 1.50; 95% CI, 1.05-2.15; P = 0.025).

CONCLUSION

Our results, and those from previous studies, suggest potential genetic contributes for GSTP1 and TERT in glioma development.

Genome-wide association analyses suggested a novel mechanism for smoking behavior regulated by IL15

Cigarette smoking is the leading preventable cause of death in the United States. Although smoking behavior has a significant genetic determination, the specific genes and associated mechanisms underlying the smoking behavior are largely unknown. Here, we carried out a genome-wide association study on smoking behavior in 840 Caucasians, including 417 males and 423 females, in which we examined approximately 380,000 single nucleotide polymorphisms (SNPs). We found that a cluster of nine SNPs upstream from the IL15 gene were associated with smoking status in males, with the most significant SNP, rs4956302, achieving a P-value (8.80 x 10(-8)) of genome-wide significance. Another SNP, rs17354547 that is highly conserved across multiple species achieved a P-value of 5.65 x 10(-5). These two SNPs, together with two additional SNPs (rs1402812 and rs4956396) were selected from the above nine SNPs for replication in an African-American sample containing 1251 subjects, including 412 males and 839 females. The SNP rs17354547 was replicated successfully in the male subgroup of the replication sample; it was associated with smoking quantity (SQ), the Heaviness of Smoking Index (HSI) and the Fagerstrom Test for Nicotine Dependence (FTND), with P-values of 0.031, 0.0046 and 0.019, respectively. In addition, a haplotype formed by rs17354547, rs1402812 and rs4956396 was also associated with SQ, HSI and FTND, achieving P-values of 0.039, 0.0093 and 0.0093, respectively. To further confirm our findings, we carried out an in silico replication study of the nine SNPs in a Framingham Heart Study sample containing 7623 Caucasians from 1731 families, among which, 3491 subjects were males and 4132 were females. Again, the male-specific association with smoking status was observed, for which seven of the nine SNPs achieved significant P-values (P<0.05) and two achieved marginally significant P-values (P<0.10) in males. Several of the nine SNPs, including the highly conserved one across species, rs17354547, are located at potential transcription factor binding sites, suggesting transcription regulation as a possible function for these SNPs. Through this function, the SNPs may modulate the gene expression of IL15, a key cytokine regulating immune function. As the immune system has long been recognized to influence drug addiction behavior, our association findings suggest a novel mechanism for smoking addiction involving immune modulation through the IL15 pathway.

Identification of PLCL1 gene for hip bone size variation in females in a genome-wide association study

Osteoporosis, the most prevalent metabolic bone disease among older people, increases risk for low trauma hip fractures (HF) that are associated with high morbidity and mortality. Hip bone size (BS) has been identified as one of the key measurable risk factors for HF. Although hip BS is highly genetically determined, genetic factors underlying the trait are still poorly defined. Here, we performed the first genome-wide association study (GWAS) of hip BS interrogating ∼380,000 SNPs on the Affymetrix platform in 1,000 homogeneous unrelated Caucasian subjects, including 501 females and 499 males. We identified a gene, PLCL1 (phospholipase c-like 1), that had four SNPs associated with hip BS at, or approaching, a genome-wide significance level in our female subjects; the most significant SNP, rs7595412, achieved a p value of 3.72×10⁻⁷. The gene's importance to hip BS was replicated using the Illumina genotyping platform in an independent UK cohort containing 1,216 Caucasian females. Two SNPs of the PLCL1 gene, rs892515 and rs9789480, surrounded by the four SNPs identified in our GWAS, achieved p values of 8.62×10⁻³ and 2.44×10⁻³, respectively, for association with hip BS. Imputation analyses on our GWAS and the UK samples further confirmed the replication signals; eight SNPs of the gene achieved combined imputed p values<10⁻⁵ in the two samples. The PLCL1 gene's relevance to HF was also observed in a Chinese sample containing 403 females, including 266 with HF and 177 control subjects. A SNP of the PLCL1 gene, rs3771362 that is only ∼0.6 kb apart from the most significant SNP detected in our GWAS (rs7595412), achieved a p value of 7.66×10⁻³ (odds ratio = 0.26) for association with HF. Additional biological support for the role of PLCL1 in BS comes from previous demonstrations that the PLCL1 protein inhibits IP3 (inositol 1,4,5-trisphosphate)-mediated calcium signaling, an important pathway regulating mechanical sensing of bone cells. Our findings suggest that PLCL1 is a novel gene associated with variation in hip BS, and provide new insights into the pathogenesis of HF.

Genetic polymorphisms of 15 STR loci in Han population from Shaanxi (NW China)

The genetic polymorphisms of 15 STR loci, namely D3S1358, D5S818, D7S820, D13S317, vWA, FGA, TH01, TPOX, CSF1PO, D16S539, D8S1179, D21S11, D18S51, D19S433 and D2S1338, were studied in 203 unrelated Han population from Shaanxi province using AmpF/STR Identifiler kit.

[Genetic relationship between minorities in Guangxi by STR markers]

OBJECTIVE

To determine the molecular genetic relationship of minorities and sub-population in Guangxi area.

METHODS

Six stable STRs (D3S1358, vWA, FGA, D5S818, D13S317 and D7S820) were selected as genetic markers. STR data of Zhuang (Yangshuo) and Yao(Wantian) were genotyped from blood samples by ABI377 sequencer. STR data of another 12 ethnic groups in Guangxi were collected from publications. Hardy-Weinberg equilibrium was evaluated and H, PIC, DP and PPE were computed. The genetic distances between different populations were calculated using Nei's method and clustering analysis was done by average linkage between the groups. We drew their phylogenetic tree using UPGMA.

RESULTS

The alleles of 6 STRs in the 15 populations of Guangxi conformed with Hardy-Weinberg equilibrium. H was distributed in 0.6482-0.9299; PIC in 0.5706-0.8662; DP in 0.8258-0.9706, and PPE in 0. 4215-0.9917. Genetic distance between Jing of Guangxi and Jing in Dongxing was minimum (0.0007) in the 15 populations, while genetic distance between Guangxi Gelao and Wantian Yao was maximal (0.2391). The phylogenetic tree was similar to the results of clustering analysis and all the 15 populations were clustered into 2 groups.

CONCLUSION

The results indicate that the H, PIC, DP and PPE of 6 STRs in the 15 Guangxi populations are comparatively high. There is gene flow in some groups, but several minorities are relatively separated.

[Genetic polymorphism of 9 STR loci in Zhuang national minority of China]

Genetic distribution for nine STR loci were determined in a Chinese Guangxi Zhuang national minority group based on STR gene scan marked by fluorescence. Sixty-two alleles and 169 genotypes were observed in 91 unrelated Zhuang individuals. The corresponding gene frequency and genotype frequency were 0.0054-0.5495 and 0.0110-0.3297 respectively. The expected and observed genotype frequency of nine STR loci was in accordance with the Hardy-Weinberg equilibrium (P > 0.05). The statistical analysis of nine STR loci showed PIC (polymorphic information content) > or = 0.6088, H (heterozygosity) > or = 0.6174, DP (discrimination power) > or = 0.8028, PPE (probability of paternity exclusion) > or = 0.8165. The genetic distance figured with 9 STR genetic data showed that there were significant differences between Chinese Zhuang national minority and the American White and the American Black, and there was little difference between Zhuang national minority and the Chinese Xi'an Han. The result of clusting showed that the present data were divided into three groups: the Black, the White and the Yellow (the Chinese).

[STR polymorphisms in five Chinese ethnic groups(2)]

Population genetic studies were performed in Chinese Han, Hui, Mongolian, Tibetan and Uygur. Allele frequency distributions were analyzed for ten loci, i.e., D3S1358, VWA, CSF1PO, FGA, THO1, TPOX, D5S818, D13S317 and D7S820 by GeneScan. The results showed that there were 60 STR alleles and 149 genotypes in Han; 63 STR alleles and 144 genotypes in Hui; 69 STR alleles and 173 genotypes in Mongolian; 77 STR alleles and 168 genotypes in Tibetan; 70 STR alleles and 148 genotypes in Uygur. Significant differences were identified among ethnic groups (African-American, US-Caucasian and Chinese-Oriental), but similarity was found among the five Chinese populations, and immunogenomics and pharmacogenomics studied in this report. These findings indicated that the nine STR loci and amelogenin locus were very useful for individual identification in forensic science.