The free amino acid profiles and metabolic biomarkers of predicting the chemotherapeutic response in advanced sarcoma patients.

PURPOSE: Metabolomics is an emerging field in cancer research. Plasma free amino acid profiles (PFAAs) have shown different features in various cancers, but the characteristic in advanced sarcoma remains unclear. We aimed to uncover the specific PFAAs in advanced sarcoma and to find the relationship between the altering of PFAAs and response to chemotherapy. PATIENTS AND METHODS: We analyzed the differences in PFAAs between 23 sarcoma patients and 30 healthy subjects basing on liquid chromatography-tandem mass spectrometry (LC-MS/MS). Then, we compared the dynamics of PFAAs after chemotherapy between improvement group and deterioration group. RESULTS: We identified seven biological differential amino acids and four pathways which were perturbed in the sarcoma patients compared with healthy subjects. After one cycle chemotherapy, the levels of γ-aminobutyric acid (GABA) and carnosine (Car) decreased significantly in the improvement group but not in deterioration group. The levels of α-aminobutyric acid (Abu) increased significantly in the deterioration group but not in the improvement group. CONCLUSION: Our study suggests the potential specific PFAAs in sarcoma patients. The unusual amino acids and metabolic pathways may provide ideas for clinical drugs targeting therapy. Three amino acids including Car, GABA and Abu may be metabolic biomarkers playing a role in dynamic monitoring of the therapeutic effect.

GRK2 desensitizes flow-induced responses in osteoblasts.

Bone desensitization after mechanical loading is essential for bone to adapt to its mechanical environment. However, the desensitization mechanism is unknown. Previous studies suggest that G protein-coupled receptors (GPCRs), including P2Y and parathyroid hormone receptors, play important roles in osteoblast mechanobiology. Thus, for the present research, we examined the role of G protein-coupled receptor kinase 2 (GRK2) in osteoblast desensitization after exposure to mechanical stimulation. We first showed the existence of osteoblast desensitization after mechanical stimulation based on cytosol Ca2+ and phosphorylated ERK1/2 activities, detected using a fluorescent Ca2+-sensitive dye and western blotting, respectively. We then demonstrated that GRK2 overexpression in MC3T3-E1 cells inhibits flow-induced ERK1/2 phosphorylation, while siRNA knockdown of GRK2 enhances ERK1/2 phosphorylation. Additionally, we found that GRK2 overexpression in MC3T3-E1 cells inhibits cyclooxygenase-2 mRNA expression in the short term and alkaline phosphatase activity in the long term. More importantly, we discovered that GRK2 translocated to the cell membrane shortly after flow stimulation - a step necessary for GPCR desensitization. Previously, we have demonstrated that P2Y2 purinergic receptors, one type of GPCRs, are involved in various flow-induced osteoblastic responses. In this research, we also showed that GRK2 overexpression does not affect ATP release. Accordingly, GRK2 is able to inhibit flow-induced osteoblast responses possibly through desensitizing P2Y2 receptors.

Effects of sacral nerve stimulation with acupuncture on gut transit time and c-kit expression in colon of rats with slow transit constipation.

Sacral nerve stimulation (SNS) is an alternative surgical approach to alleviate fecal incontinence and constipation. This study aimed to explore the effects and underlying mechanisms of SNS with acupuncture on gut transit time and colon c-kit protein expression in rats with slow transit constipation (STC). Fifty Sprague-Dawley rats were randomly divided into five groups: blank control, SNS, Mosapride, sham SNS, and STC model control group. The STC model was established by subcutaneous injection of morphine. Each group was treated over a 15-day period. Gut transit time was measured 1 day before the treatment started and after 5, 10, and 15 days of treatment. After the 15-day treatment, animals were sacrificed and colonic tissues were collected for analysis of c-kit protein expression, using western blot analysis. We found significant differences in gut transit time in the SNS group compared with the Mosapride group after 5 (P = 0.001) and 10 (P = 0.004) days of treatment. After 15 days of treatment, there were no differences in gut transit time among the SNS, Mosapride, and blank control groups. However, significant differences were observed when comparing the SNS and Mosapride groups with the STC model and sham SNS groups. A decreased c-kit protein expression was observed in the STC model control, sham SNS, and Mosapride groups, compared with the SNS group (P = 0.001). Our data indicate that SNS can decrease gut transit time and increase the expression of c-kit protein in rats with STC to improve colon transit function.

Modified Da Chengqi granules improvement in immune function in early severe acute pancreatitis patients.

We investigated the role of modified Da Chengqi granules in improving immune function in early severe acute pancreatitis patients. Early severe acute pancreatitis patients who agreed to receive combined treatment of traditional Chinese and Western medicine were randomly assigned to the experimental or control group. All subjects received conventional therapy to support organ function. The experimental group also received modified Da Chengqi granules. Cytokine (interleukin-6, interleukin-10, and tumor necrosis factor-α) levels, immunological markers (HLA-DR, Treg, and Th1/Th2), urinary lactulose/mannitol ratio, and endotoxin levels were measured at 1, 3, 7, and 14 days after hospital admission. The total mortality rate was 11.69% (9/77), which was significantly lower in the experimental group [4.88% (2/41)] than in the control group [19.44% (7/36); χ(2) = 3.940, P < 0.05]. Serum interleukin-6, interleukin-10, tumor necrosis factor-α and endotoxin levels and the lactulose/mannitol ratio were significantly lower on day 7 and day 14 than on day 1 in experimental and control groups (P < 0.01). Immunological indices were significantly lower in the experimental group than in the control group on day 14 (all P < 0.01 or 0.05). HLA-DR-positive cell ratio gradually increased over 14 days in experimental and control groups (P < 0.01 vs day 1), but was higher in the experimental group than in the control group by day 14 (P < 0.05). Notably, Treg cell prevalence and Th1/Th2 cell ratio deteriorated within 7 days in both groups (P < 0.01 vs day 1), but then returned to day 1 levels (P < 0.01 or 0.05 vs day 1). Significant differences in Treg levels and Th1/Th2 cell ratio between experimental and control groups were observed on day 14 (P < 0.01). These results show that modified Da Chengqi granules can improve immune function in early severe acute pancreatitis patients.

Analysis of polymorphisms in milk proteins from cloned and sexually reproduced goats.

This study evaluates the relationship between the genotype and milk protein components in goats. Milk samples were collected from cloned goats and normal white goats during different postpartum (or abortion) phases. Two cloned goats, originated from the same somatic line of goat mammary gland epithelial cells, and three sexually reproduced normal white goats with no genetic relationships were used as the control. The goats were phylogenetically analyzed by polymerase chain reaction-restriction fragment length polymorphism. The milk protein components were identified by sodium dodecyl sulfate polyacrylamide gel electrophoresis. The results indicated that despite the genetic fingerprints being identical, the milk protein composition differed between the two cloned goats. The casein content of cloned goat C-50 was significantly higher than that of cloned goat C-4. Conversely, although the genetic fingerprints of the normal white goats N-1, N-2, and N-3 were not identical, the milk protein profiles did not differ significantly in their milk samples (obtained on postpartum day 15, 20, 25, 30, and 150). These results indicated an association between milk protein phenotypes and genetic polymorphisms, epigenetic regulation, and/or non-chromosomal factors. This study extends the knowledge of goat milk protein polymorphisms, and provides new strategies for the breeding of high milk-yielding goats.

Angiotensin II type 1 receptor gene A1166C polymorphism and breast cancer susceptibility.

Numerous studies have evaluated the association between the angiotensin II type-1 receptor (AGTR1) gene A1166C polymorphism and breast cancer risk. However, the specific association is controversial. The aim of the present study was to derive a more precise estimation of the relationship. A comprehensive research was conducted of the PubMed and the Google Scholar databases through February 2015. Data were assessed using STATA version 12.0. Pooled odds ratios with 95%CIs were derived from the fixed-effect or random-effect models. A total of 911 patients with breast cancer and 1284 controls from 5 case-control studies were included in this meta-analysis. The meta-analysis results showed no significant association between the AGTR1 gene A1166C polymorphism and breast cancer risk. Similarly, in the subgroup analysis regarding ethnicity, no associations were observed. Heterogeneity and publication bias were not observed in this meta-analysis. The A1166C polymorphism in the AGTR1 gene may not be a risk factor for breast cancer. Further, large, and well-designed studies are needed to confirm this conclusion.

Identification of conserved microRNAs in peripheral blood from giant panda: expression of mammary gland-related microRNAs during late pregnancy and early lactation.

The giant panda (Ailuropoda melanoleuca) is one of the world's most endangered mammals, and it has evolved several unusual biological and behavioral traits. During puberty, pregnancy, lactation, and involution, the mammary gland undergoes profound morphological and functional changes. A large number of microRNAs (miRNAs) have been identified to be involved in mammary gland development and lactation. In this study, we identified 202 conserved mature miRNAs, corresponding to 147 pre-miRNAs, in giant panda peripheral blood using a small RNA-sequencing approach. In addition, 27 miRNA families and 29 miRNA clusters were identified. We analyzed the arm selection preference of pre-miRNAs and found that: 1) most giant panda pre-miRNAs generated one-strand miRNAs, and the 5p-arm only miRNAs have a higher expression level than 3p-arm only miRNAs; 2) there were more 5p-arm dominant miRNAs than 3p-arm dominant miRNAs; and 3) 5p-arm dominant miRNAs have a larger fold change within miRNA pairs than 3p-arm dominant miRNAs. Expression of 12 lactation-related miRNAs was detected across late pregnancy and early lactation stages by qPCR, and seven miRNAs were identified as clustered in one significant model. Most of these clustered miRNAs exhibited inhibitory roles in proliferation and differentiation of mammary epithelial cells. Functional analysis highlighted important roles of the seven as signed miRNAs in mammary development and metabolic changes, including blood vessel morphogenesis, macromolecule biosynthesis, cell cycle regulation, and protein transport.

Gene annotation and functional analysis of a newly sequenced Synechococcus strain.

Synechococcus sp PCC 7336 represents a newly sequenced strain, and its genome is obviously different from that of other Synechococcus strains. In this analysis, local alignment and annotation databases were constructed and combined with various bioinformatic tools to carry out gene annotation and functional analysis of this strain. From this analysis, we identified 5096 protein-coding genes and 47 RNA genes. Of these, 116 genes that were classified into 9 categories were associated with photosynthesis, and type V polymerase proteins that were identified are unique for this strain. An additional 107 genes were closely related to signal transduction pathways, which primarily comprised parts of two-component regulatory systems. Gene ontogeny analysis showed that 2377 genes were annotated with a total number of 9791 functional categories, and specifically that 41 genes distributed in 4 protein complexes were involved in oxidative phosphorylation. Clusters of orthologous groups classification showed that there were 1463 homologous proteins associated with 17 specific metabolic pathways, and that most of the proteins participated in primary metabolic processes such as binding and catalysis. The phylogenetic tree based on 16S rRNA sequences indicated that Synechococcus PCC 7336 is highly likely to represent a new branch.

Association between five common polymorphisms in microRNA genes and the risk of gastric cancer: a meta-analysis.

Gastric cancer (GC) is a prevalent disease with a high mortality rate, especially in developing countries. Accumulating evidence suggests that single nucleotide polymorphisms in microRNA (miRNA) genes might influence the susceptibility to GC; such sequence variation might contribute to the development of disease by altering crucial cellular pathways. In this study, we assessed the correlation between the miR-146a G>C, miR-196a-2 C>T, miR-499 T>C, miRNA-27a A>G, and miRNA-149 T>C polymorphisms and the susceptibility to GC. A comprehensive literature search for relevant studies published prior to August 2014 was conducted using PubMed/Medline, Embase, Web of Science, the Cochrane Library, and CNKI databases along with Google Scholar. Meta-analysis was performed using odds ratios (ORs) and 95% confidence intervals (CIs) as effect measures, incorporating 19 studies encompassing 8285 patients and 10,716 controls. Allelic, dominant, recessive, homozygous, and heterozygous genetic models were examined. Pooled results showed that none of the five polymorphisms studied were statistically related to GC. Stratified analyses by ethnicity and source of controls were conducted for miR- 146a G>C and miR-196a-2 C>T. Subgroup analysis suggested that the miR-146a G allele might increase the risk of GC in hospital-based case-control (HCC) but not in population-based case-control studies (HCC: recessive model: OR = 1.23, 95%CI = 1.10-1.37, P < 0.001; heterozygous model: OR = 1.19, 95%CI = 1.06-1.34, P = 0.004). Overall, this meta-analysis failed to detect an association between five common miR-146a gene polymorphisms and GC susceptibility. However, this does not necessarily completely rule out a correlation between miRNA polymorphisms and GC susceptibility.

Genome-wide association study of meat quality traits in chicken.

Meat quality traits are very important in the poultry industry. To identify single nucleotide polymorphisms (SNPs) and candidate genes affecting meat quality traits, a genome-wide association study was performed using the Illumina chicken 60K SNP beadchip in Jinghai yellow chicken. Four meat quality traits were measured. Two SNPs reached 5% Bonferroni genome-wide significance (P < 1.8E-6) and 7 SNPs reached "suggestive" genome-wide significance (P < 3.59E-6) with meat quality. These SNPs were located nearby or in 7 candidate genes, including CBLN2, HPGDS, SETD2, and ANKRD46, among others. A total of 5650 haplotpyes were established and only 1 was found to be associated with fat content in leg muscle. These results indicate that the 9 SNPs and 7 genes are important candidate markers and may influence meat quality traits in chicken.

Craniocervical decompression with duraplasty and cerebellar tonsillectomy as treatment for Chiari malformation-I complicated with syringomyelia.

This study aimed to investigate the therapeutic effects of craniocervical decompression with duraplasty and cerebellar tonsillectomy for the treatment of Chiari malformation-I with syringomyelia (CM I-SM). From January 2005 to December 2011, 127 patients with CM I-SM underwent craniocervical decompression with duraplasty and cerebellar tonsillectomy and the therapeutic effects of these surgeries were evaluated using Tator scores. No patient in this study died or showed disease deterioration after the surgery. Re-examination by magnetic resonance imaging (MRI) showed that the cisterna magna was obviously larger after the operation in all but one patient. Moreover, syringomyelia (SM) was reduced in 76 patients. CM I-SM symptoms disappeared or decreased in 112 patients after following discharge. Follow-up was conducted in 84 of the patients and 79 of these patients exhibited improved symptoms. A second MRI re-examination showed that the cisterna magna was successfully constructed in 44 patients; 42 of these patients showed further eliminated or obviously reduced SM. Craniocervical decompression with duraplasty and cerebellar tonsillectomy achieved favorable therapeutic effects. Thus, craniocervical decompression with duraplasty and cerebellar tonsillectomy is a rational surgical approach with beneficial clinical effects. The proposed approach may have useful applications in the treatment of CM I-SM.

Developmental changes in the expression of the GLUT2 and GLUT4 genes in the longissimus dorsi muscle of Yorkshire and Tibetan pigs.

Glucose transporter proteins 2 and 4 (GLUT2 and GLUT4) play important roles in glucose transport and energy metabolism. Changes in the levels of GLUT2 and GLUT4 mRNA were measured in longissimus dorsi muscle from the lean Yorkshire and fat Tibetan pig breeds at six different time points (1, 2, 3, 4, 5, and 6 months) with quantitative real-time polymerase chain reactions. The results showed that GLUT2 and GLUT4 mRNA were abundantly expressed in the longissimus dorsi muscle and that the developmental expression patterns were similar in both breeds. Tibetan pigs exhibited higher intramuscular fat and GLUT2 mRNA levels, while Yorkshire pigs exhibited a higher myofiber cross-sectional area (CSA) and GLUT4 mRNA levels. Furthermore, the changes in the GLUT4 mRNA levels were strongly and positively correlated with the CSA over a period of six months. These results exhibit time- and breed-specific expression patterns of GLUT2 and GLUT4, which highlight their potential as candidate genes for assessing adipose deposition and muscle development in pigs. These differences in the expression of GLUT family genes may also have indications for meat quality.

Two novel ATP2C1 mutations in patients with Hailey-Hailey disease and a literature review of sequence variants reported in the Chinese population.

Hailey-Hailey disease (HHD) is an autosomal dominant disorder in which the ATP2C1 gene has been implicated. Many mutations of this gene have been detected in HHD patients. To analyze such mutations in HHD and summarize all those identified in Chinese patients with this disease, we examined four familial and two sporadic cases and searched for case reports and papers by using the Chinese Biological Medicine Database and PubMed. HHD diagnoses were made based on clinical features and histopathological findings. Polymerase chain reaction and direct sequencing of the ATP2C1 gene were performed using blood samples from HHD patients, unaffected family members, and 120 healthy individuals. Three mutations were identified, including the recurrent mutation c.2126C>T (p.Thr709Met), and two novel missense mutations, c.2235_2236insC (p.Pro745fs*756) and c.689G>A (p.Gly230Asp). Considering our data, 81 different mutations have now been reported in Chinese patients with HHD. In cases of misannotation or duplication, previously published mutations were renamed according to a complementary DNA reference sequence. These mutations are scattered throughout the ATP2C1 gene, with no evident hotspots or clustering. It is of note that some reported "novel" mutations were in fact found to be recurrent. Our findings expand the range of known ATP2C1 sequence variants in this disease.

Role of miR-149C>T polymorphisms on the risk of hepatocellular carcinoma in a Chinese population.

MicroRNAs (miRNAs) are thought to play a role in cancer development. We conducted a case-control study to investigate the association between polymorphisms in miR-149C>T and hepatocellular carcinoma (HCC) risk. Duplex polymerase chain reaction with the confronting 2-pair primers were taken to genotype miR-149C>T. The association between genotype frequencies of miR-149C>T and risk of HCC was estimated as odds ratios (ORs) and 95% confidence intervals (95%CIs) using conditional regression analysis. Logistical regression analysis showed that the miR-149 CC genotype and C allele were associated with risk of HCC, with adjusted ORs (95%CI) of 2.07 (1.32-3.26) and 1.42 (1.06-2.12), respectively. Using the TT+TC genotype as a reference, individuals carrying the CC genotype were associated with non-significant increased risk of HCC, adjusted OR (95%CI) of 1.37 (0.91-2.07). Subgroup analysis showed that HBV-infected subjects carrying the miR-149 TC+CC genotype (OR=5.85, 95%CI=2.49-13.77) had an increased risk of HCC. In summary, our study found that miRNA-149C>T polymorphism is associated with risk of HCC, especially in HBV-infected patients.

Single-nucleotide polymorphism analysis of GH, GHR, and IGF-1 genes in minipigs

Tibetan (TB) and Bama (BM) miniature pigs are two popular pig breeds that are used as experimental animals in China due to their small body size. Here, we analyzed single-nucleotide polymorphisms (SNPs) in gene fragments that are closely related to growth traits [growth hormone (GH), growth hormone receptor (GHR), and insulin-like growth factor (IGF)-1)] in these pig breeds and a large white (LW) control pig breed. On the basis of the analysis of 100 BMs, 108 TBs, and 50 LWs, the polymorphic distribution levels of GH, GHR, and IGF-1 were significantly different among these three pig breeds. According to correlation analyses between SNPs and five growth traits - body weight (BW), body length (BL), withers height (WH), chest circumference (CC), and abdomen circumference (AC) - three SNP loci in BMs and four SNP loci in TBs significantly affected growth traits. Three SNP sites in BMs and four SNP sites in TBs significantly affected growth traits. SNPs located in the GH gene fragment significantly affected BL and CC at locus 12 and BL at locus 45 in BMs, and also BW, WH, CC, and AC at locus 45 and WH and CC at locus 93 in TBs. One SNP at locus 85 in the BM GHR gene fragment significantly affected all growth traits. All indices were significantly reduced with a mixture of alleles at locus 85. These results provide more information regarding the genetic background of these minipig species and indicate useful selection markers for pig breeding programs.

Single-nucleotide polymorphism analysis of GH, GHR, and IGF-1 genes in minipigs.

Tibetan (TB) and Bama (BM) miniature pigs are two popular pig breeds that are used as experimental animals in China due to their small body size. Here, we analyzed single-nucleotide polymorphisms (SNPs) in gene fragments that are closely related to growth traits [growth hormone (GH), growth hormone receptor (GHR), and insulin-like growth factor (IGF)-1)] in these pig breeds and a large white (LW) control pig breed. On the basis of the analysis of 100 BMs, 108 TBs, and 50 LWs, the polymorphic distribution levels of GH, GHR, and IGF-1 were significantly different among these three pig breeds. According to correlation analyses between SNPs and five growth traits--body weight (BW), body length (BL), withers height (WH), chest circumference (CC), and abdomen circumference (AC)--three SNP loci in BMs and four SNP loci in TBs significantly affected growth traits. Three SNP sites in BMs and four SNP sites in TBs significantly affected growth traits. SNPs located in the GH gene fragment significantly affected BL and CC at locus 12 and BL at locus 45 in BMs, and also BW, WH, CC, and AC at locus 45 and WH and CC at locus 93 in TBs. One SNP at locus 85 in the BM GHR gene fragment significantly affected all growth traits. All indices were significantly reduced with a mixture of alleles at locus 85. These results provide more information regarding the genetic background of these minipig species and indicate useful selection markers for pig breeding programs.

Effect of MPO/H2O2/NO(-) system on nitric oxide-mediated modification of TTR amyloid and serum TTR in FAP ATTR Val30Met patients.

Amyloid deposits consist of protein fibrils and amorphous material, and this deposition is related to oxidative stress. Previously, we demonstrated the presence of high-density lipoproteins and/or lipids in amyloid deposits of familial amyloid polyneuropathy patients. In this study, the presence of myeloperoxidase (MPO) in amyloid deposits was demonstrated using immunohistochemical staining. In contrast, normal surrounding tissues were consistently negative for MPO. Nitrotyrosine was present in amyloid deposits after being exposed to the MPO/H2O2/NO(-) system by immunohistochemical staining, and the oxide mediated modification of serum transthyretin (TTR) was observed upon exposure to the MPO/H2O2 system using two-dimensional gel electrophoresis and TTR Western blotting. This observation revealed that the TTR amyloid deposits and serum TTR were oxidized by the MPO/H2O2/NO(-) system. Nitric oxide-mediated modification of TTR may play a role in amyloidogenesis in vivo.

Associated analysis of single nucleotide polymorphisms found on exon 3 of the IGF-1 gene with Tibetan miniature pig growth traits.

The IGF-1 gene is an important regulating factor that has a growth-promoting effect on growth hormone. The IGF-1 gene promotes muscle cell differentiation in the muscle cell formation process. The IGF-1 gene also regulates the growth of skeletal muscle during skeletal muscle growth. In addition, the IGF-1 gene plays an important role in the formation of mammals and poultry embryos, and the process of postnatal growth. The IGF-1 gene has been implicated as a candidate gene for the regulation of pig growth traits. We analyzed exon 3 of the IGF-1 gene polymorphism in Tibetan miniature pigs (N = 128) by polymerase chain reaction-single-strand conformation polymorphism and DNA sequencing. One single nucleotide polymorphism (T40C) was found on exon 3 of the IGF-1 gene. Statistical analysis of genotype frequencies revealed that the T allele was dominant in Tibetan miniature pigs at the T40C locus. The association analysis showed that the IGF-1 mutation had an effect on the body weight, body length, and chest circumference of pigs aged 6-8 months. In addition, the IGF-1 mutation had an effect on body weight in pigs aged 9-11 months (P < 0.05). We speculated that the pigs with the TT genotype grow more rapidly compared to those with the TC genotype. The TC genotype of the Tibetan miniature pig has a smaller body type. This information provides a theoretical basis for the genetic background of Tibetan miniature pigs.

Genetic variations of ISL1 associated with human congenital heart disease in Chinese Han people.

Congenital heart disease (CHD) is the most common birth abnormality, but the etiology of CHD is unknown. ISL1 may play a fundamental role in cardiac morphogenesis, and mutations of this gene could cause CHD. To evaluate whether genetic variations of ISL1 are associated with CHD in Chinese Han people, polymerase chain reaction restriction fragment-length polymorphism and SNaPshot were used to examine 9 polymorphisms of ISL1 in 233 patients with CHD as well as 288 healthy controls. We found that one SNP (rs1017) in ISL1 was significantly associated with simple CHD. Genetic variation of ISL1 was confirmed to be associated with the risk of CHD. ISL1 is related to the atrial septal defect group and the ventricular septal defect group, and the genotypes were associated with the occurrence of CHD in the dominant mode of inheritance. We concluded that rs1017 contributed to the risk of CHD in Chinese Han people, and ISL1 may be involved in the formation and development of the heart.

Meta-analysis of the cytotoxic T-lymphocyte antigen 4 gene +6230G/A polymorphism and cancer risk.

OBJECTIVES: Cytotoxic T-lymphocyte antigen-4 (CTLA4, CD152) is one of the most fundamental immunosuppressive cytokines that inhibits T-cell activation and terminates the T-cell response by blocking signals stimulated via CD28. A number of studies have assessed the association between CTLA-4 +6230G/A polymorphism and cancer risk. However, the results remain controversial. METHODS: In the present study, we performed a meta-analysis to derive a more precise estimation of the relationship. A comprehensive literature search was performed using the PubMed database for relevant articles published (updated to November 21, 2013). Odds ratios (ORs) and 95 % confidence intervals (CIs) were used to assess the strength of the association. RESULTS: A total of 13 articles with 14 studies were selected for this meta-analysis, including 4,489 cases and 4,715 controls. Combined analysis revealed no associations between CTLA-4 +6230G/A polymorphism and cancer risk. However, in stratified analysis by cancer type, we found that CTLA-4 +6230G/A polymorphism was associated with the risk of breast cancer (AA vs. AG + GG: OR = 0.77, 95 % CI 0.60-0.97, P = 0.03; AA vs. GG: OR = 0.66, 95 % CI 0.46-0.95, P = 0.02) and cervical cancer (AA vs. AG + GG: OR = 0.56, 95 % CI 0.42-0.75, P < 0.01). Additionally, in subgroup analysis based on ethnicity, significant association was also found between the CTLA-4 +6230G/A polymorphism and cancer risk in the Asian population (AA vs. AG + GG: OR = 0.71, 95 % CI 0.59-0.84, P < 0.01). CONCLUSION: This meta-analysis indicates that CTLA-4 +6230G/A polymorphism may be associated with a decreased risk of breast cancer and cervical cancer in Chinese population.