A let-7 KRAS rs712 polymorphism increases colorectal cancer risk.

Growing evidence has indicated that polymorphism present in the miRNA binding site of target gene can alter the ability of miRNAs to bind its target gene and modulate the development and progression of cancer. We aimed to investigate the association between let-7 KRAS rs712 polymorphism and the risk of colorectal cancer (CRC). The let-7 KRAS rs712 was analyzed in a case-control study, including 339 CRC patients and 313 age- and sex-matched controls; the relationship between the polymorphism and the clinicopathological features of CRC was also examined. Individuals carrying the let-7 KRAS rs712 TT genotype and T allele had an increased risk of developing CRC (TT vs. GG, adjusted OR = 2.18; 95% CI, 1.00-4.77; T vs. G, adjusted OR = 1.50; 95% CI, 1.15-1.96). Stratified analyses revealed that CRC patients with the let-7 KRAS rs712 TT genotype were more likely to have clinical stage III or IV disease (OR = 3.29, 95% CI, 1.32-8.20) and distant metastasis (OR = 4.70, 95% CI, 1.81-12.25). These findings provide evidence that the let-7 KRAS rs712 polymorphism may play crucial roles in the etiology of CRC.

A genetic variant in the promoter region of miR-34b/c is associated with a reduced risk of colorectal cancer.

The miR-34 family members, described as potential tumor suppressors, were downregulated in colorectal cancer (CRC). Loss of miR-34 impairs TP53-mediated cell death, while overexpression of miR-34 induces apoptosis. A potentially functional polymorphism (i.e., rs4938723T/C) in the promoter region of pri-miR-34b/c was predicted to influence the GATA-X binding sites. We aimed to investigate the association between miR-34b/c rs4938723 and TP53 Arg72Pro polymorphisms and the risk of CRC. We genotyped the two polymorphisms in 347 CRC patients and 488 healthy controls using polymerase chain reaction-restriction fragment length polymorphism and DNA sequencing assay. We found that the CC genotype and C allele of the miR-34b/c rs4938723 were associated with a significantly decreased risk of CRC compared with the TT genotype and T allele (CC vs. TT: adjusted OR=0.56; 95% CI, 0.34-0.91; C vs. T: adjusted OR=0.78; 95% CI, 0.64-0.97). In combined analysis, a borderline significance was also observed in subjects carrying the rs4938723 CT/CC and TP53 GG genotypes (adjusted OR=0.66; 95% CI, 0.43-0.99). These findings indicate that the rs4938723 in the promoter region of pri-miR-34b/c was a protective factor for the development of CRC. As the significance is marginal, further replication studies are warranted to confirm these results.

A let-7 binding site polymorphism rs712 in the KRAS 3' UTR is associated with an increased risk of gastric cancer.

Recently, single nucleotide polymorphisms in let-7 miRNA binding site in 3' untranslated region (UTR) of KRAS mRNA have been found to be associated with the cancer risk. In this study, we genotyped the frequency of KRAS rs712 to test its effect on gastric cancer (GC) risk in a hospital-based case-control study in a Chinese population, with 181 histologically confirmed GC patients and 674 cancer-free controls, using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay. The TT genotype of rs712 was associated with an increased risk of GC when taking GG genotype as a reference (adjusted odds ratio (OR) = 3.05, 95 % confidence interval (CI), 1.53-6.08). Similarly, the T allele of rs712 was associated with a statistically significant increase in susceptibility compared with G allele (adjusted OR = 1.44, 95 % CI, 1.10-1.90). Our data demonstrated that the T allele of the let-7 binding site polymorphism rs712 in KRAS 3' UTR was associated with a significantly increased risk of GC, suggesting that the KRAS rs712 polymorphism may be a genetic marker for the development of GC.

[Expression of SSB following early myocardial ischemia in rats].

OBJECTIVE: To investigate the expression of Sjögren's syndrome antigen B (SSB) gene and SSB protein in the early ischemic myocardium in rats. METHODS: Adult healthy Sprague-Dawley rats were randomly divided into groups of operation [myocardial ischemia (MI) and non-ischemia (NI)], non-operation (NO) and sham-operation (SO) (n = 6 for MI and NI; n = 4 for NO and SO). According to time of ischemia, it was then divided into groups of 0 min, 15 min, 30 min, 60 min, 120 min, and 240 min. The expression of SSB gene in the myocardium was examined by real-time PCR, and the expression of SSB protein was examined by Western blot and immunofluorescence staining. RESULTS: The expressions of SSB gene was down-regulated at early stage of ischemia. There was significant difference between 0 min and 120 min at the level of expression of SSB gene in MI group, so did that between 120 min group and NO group (P < 0.05). The expression of SSB protein at 60 min after ischemia was significantly decreased compared with that in the group of 0 min (P < 0.05). The expression of SSB protein in NI groups was significantly higher than that in MI groups at the time of 60 min and 120 min after myocardial ischemia (P < 0.05). Additionally, the expression of SSB protein was mainly located in the myocardial nucleus, myocardial plasma, and plasma membrane of partial myocardiocytes according to the result of immunofluorescence staining. CONCLUSION: SSB may participate in pathophysiologic regulation process in myocardial cells at the early stage of myocardial ischemia in rats.

Interactions of interleukin-12A and interleukin-12B polymorphisms on the risk of intracranial aneurysm.

Several lines of evidence indicate that inflammatory processes play pivotal role in the development of intracranial aneurysm (IA). Recently, polymorphisms in the interleukin-12 (IL-12) gene were shown to be associated with immune-mediated inflammatory disease. The aim of this study was to investigate the interactions of IL-12A and IL-12B polymorphisms on the risk of IA in a Chinese population. A total of 422 individuals (including 164 patients with IA and 258 controls) were involved in the study. The polymorphisms (i.e., rs2243115 and rs568408 in IL-12A and rs3212227 in IL-12B) were genotyped by polymerase chain reaction-restriction fragment length polymorphism assay and DNA sequencing. We found an association of the AC/CC genotypes and C allele of IL-12B rs3212227 with an increased risk of IA, compared with the AA genotype and A allele (AC/CC vs. AA: OR = 2.09, 95 % CI: 1.29-3.38; C vs. A: OR = 1.45, 95 % CI: 1.10-1.91). Moreover, a significant gene interaction of IL-12A and IL-12B was evident on the risk of IA, and subjects carrying variant genotypes of IL-12B rs3212227 had an increased risk of IA. In the stratified analysis by gender, the IL-12B rs3212227 AC/CC genotypes had an increased risk of IA compared with the AA genotype in male patients (AC/CC vs. AA: OR = 4.63, 95 % CI: 1.92-11.16). These findings suggest that the IL-12A and IL-12B independently and jointly be involved in the susceptibility to IA.

The association between two polymorphisms in pre-miRNAs and breast cancer risk: a meta-analysis.

Emerging evidence has shown that miRNAs participate in human carcinogenesis as tumor suppressors or oncogenes. Single nucleotide polymorphism (SNP) which located in the pre-miRNA may affect the processing and then influence the expression of mature miRNA. Previous studies yielded conflicting results as to the association of two common polymorphisms in pre-miRNAs (i.e. hsa-miR-146 rs2910164 and hsa-miR-196a2 rs11614913) with breast cancer. To derive a more precise effect on the association between these polymorphisms and breast cancer risk, we conducted a meta-analysis. Through retrieving PubMed for the period up to May 2010, a total of four studies were identified with 3,007 cases and 3,718 controls for has-miR-146a rs2910164 polymorphism and with 3,287 cases and 4,298 controls for hsa-miR-196a2 rs11614913 polymorphism. We found that individuals carrying CC genotype of has-miR-196a2 rs11614913 polymorphism was associated with an increased breast cancer risk in homozygote comparison (OR = 1.30; 95% CI, 1.01-1.68), and dominant model (OR = 1.11; 95% CI, 1.01-1.23). However, no significant association between has-miR-146a rs2910164 polymorphism and breast cancer risk was observed in all comparison models tested. These findings suggest that has-miR-196a2 rs11614913 polymorphism may play crucial roles in breast cancer development.

RAD51 135G/C polymorphism and breast cancer risk: a meta-analysis from 21 studies.

Growing evidence suggests that RAD51 plays a pivotal role in the repair of DNA double-strand breaks and the maintenance of genomic stability. A single nucleotide polymorphism, 135G/C, has been identified in the 5' untranslated region of the RAD51 gene and has been shown to influence gene transcription activity. Previous studies yielded conflicting results as to the association of 135G/C polymorphism with breast cancer. We aimed to assess the effect of 135G/C of RAD51 on breast cancer susceptibility with the use of a meta-analysis. We performed a meta-analysis of 21 published case-control studies up to April 2010. We found that the CC genotype was associated with a significantly increased risk of breast cancer when compared with the GG, CG, and CG/GG genotypes. Subgroup analyses showed that individuals carrying the CC genotype were associated with an elevated tumor risk in European populations and in sporadic breast cancer. After stratified analyses according to manuscript quality, the CC genotype was associated with a significantly increased risk of breast cancer compared with the CG genotype in studies of both higher and lower quality. However, significantly elevated risk was found in studies of higher quality, but not in studies of lower quality when homozygote and a recessive comparison model were tested. This meta-analysis indicates that RAD51 135G/C polymorphism may be identified as a susceptibility locus for breast cancer.

The association between MLH1 -93 G>A polymorphism of DNA mismatch repair and cancer susceptibility: a meta-analysis.

DNA mismatch repair, known as a fundamentally biological pathway, plays key roles in maintaining genomic stability, eliminating mismatch bases and preventing both mutagenesis in the short term and cancerogenesis in the long term. Polymorphisms of MLH1 in individuals may have an effect on the DNA repair capacity and therefore on cancer risk. Recently, emerging studies have been done to evaluate the association between MLH1 -93 G/A polymorphism and cancer risk in diverse populations. However, the results remain conflicting rather than conclusive. In this meta-analysis, we assessed reported studies of association between the MLH1 -93 G/A polymorphism and cancer risk including 13 691 cancer cases and 14 068 controls from 17 published studies. A borderline significant association between the MLH1 -93 G/A polymorphism and cancer risk was observed in overall analysis [heterozygote: odds ratio (OR) = 1.15; 95% confidence interval (CI) 1.05-1.26; homozygote: OR = 1.21; 95% CI, 1.04-1.40; dominant model: OR = 1.13; 95% CI 1.01-1.26; recessive model: OR = 1.21; 95% CI 1.07-1.35, respectively]. In subgroup analysis by ethnicity, significantly increased risks were found in Asian population and mixed population but not in Caucasian population. After stratified analysis according to the quality of literature, increased cancer risks were observed in the studies of lower quality but not in the studies of higher quality. Similarly, elevated cancer risks were observed in hospital-based studies but not in population-based studies. These findings showed no persuasive evidence that MLH1 -93 G/A polymorphism was associated with an increased risk of cancer. On the conservative standpoint, well-designed population-based studies with larger sample size in different ethnic groups should be performed to further confirm these results.

Genetic polymorphisms of DNA repair gene XRCC1 and risk of uterine leiomyoma.

The objective was to study the relationship between the polymorphisms of the DNA repair gene XRCC1 Arg399Gln, Arg194Trp, and Arg280His uterine leiomyoma in a Chinese population. In the case-control study, we compared the XRCC1 gene polymorphism of 136 uterine leiomyoma patients and 140 healthy controls by using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The results suggested that the genotype Arg/Arg of codon 280 was significantly different from its heterozygote (odds ratio [OR] = 3.633, 95% confidence interval [CI]: 2.147-6.148). In conclusion, the results suggest that polymorphism of XRCC1 Arg280His was associated with the increased risk of uterine leiomyoma in a Chinese population.

[Expression of SSB gene in rats with early isehemic myocardium and its implications].

OBJECTIVE: To examine the expression of Sjögren's syndrome antigen B (SSB) gene in rats with early ischemic myocardium. METHODS: Adult healthy Sprague-Dawley rats were randomly divided into four groups (ischemia (MI), non-ischemia (NI), sham-operated (SO) and normal control (NO) groups). The expression of SSB and beta-actin gene in the myocardium was examined by real time PCR at 0 min, 5 min, 15 min, 30 min, 60 min, 120 min after ligation of the left anterior descending coronary artery (LAD). RESULTS: The expression of SSB gene was down-regulated after ischemia. Significantly lower expression of the gene in the rats with myocardial ischemia was found at 120 min after ligation compared with those before ligation and the control group at 120 min after ligation (P < 0.05 ). However, no significant differences were found between other groups (P > 0.05). CONCLUSION: SSB gene may be involved in the pathophysiologic regulating process in myocardial cells at the early stage of myocardial ischemia in rats.

[The expression of Basigin mRNA in early ischemic myocardium and non-ischemic myocardium].

OBJECTIVE: To investigate the expression of Basigin mRNA in early ischemic myocardium (EIM) and non-ischemic myocardium (NIM) in rat. METHODS: Real-time polymerase chain reaction (PCR) technique was applied for detecting Basigin mRNA and beta-actin expression in EIM and NIM at 0 min, 15 min, 30 min, and 60 min. RESULTS: No significant differences of the Basigin mRNA expression in EIM and NIM between 0 min and sham operation (SO) or non-operation group (P > 0.05) were observed. Basigin mRNA expression in EIM significantly decreased in 15 min, 30 min, and 60 min group compared with that of 0 min group, respectively (P < 0.001). However, we failed to find any significant difference in NIM and NO from 0 min to 60 min. Basigin mRNA expression in EIM decreased significantly compared with that of in NIM (P < 0.05) after myocardial ischemia for 30 min. CONCLUSION: Basigin was involved in myocardium pathophysiology process after myocardial ischemia for 30 min, indicating that Basigin may be identified as a predictor of early myocardial ischemia in forensic medicine.

The association of interleukin-16 polymorphisms with IL-16 serum levels and risk of colorectal and gastric cancer.

Interleukin (IL)-16, a multifunctional cytokine, plays a fundamental role in inflammatory diseases, as well as in the development and progression of tumors. Genetic variation in the DNA sequence of the IL-16 gene may lead to altered cytokine production and/or activity, and this variation may modulate an individual's susceptibility to both colorectal cancer (CRC) and gastric cancer (GC). To test this hypothesis, we investigated the association of IL-16 gene polymorphisms with serum levels of IL-16 and the risk of CRC and GC in a Chinese population. We analyzed single-nucleotide polymorphisms of the IL-16 gene in 596 cancer patients (376 patients with CRC and 220 patients with GC), and also in 480 age- and sex-matched controls using polymerase chain reaction-restriction fragment length polymorphism and DNA sequencing methods. Serum IL-16 levels were measured by enzyme-linked immunosorbent assay. The rs11556218 T/G polymorphism of the IL-16 gene was significantly associated with the susceptibility to CRC and GC patients. Both male and female patients carrying the G allele had a significantly higher risk for developing CRC and GC compared with individuals carrying the T allele. Alternatively, women carrying the T allele (rs4072111 C/T) showed a decreased risk for CRC and GC compared with individuals carrying the C allele. In patients with CRC or GC, IL-16 serum levels were significantly higher than those in the healthy controls, although no significant association between IL-16 polymorphisms and serum levels of IL-16 was observed. Our data indicate that IL-16 polymorphisms may contribute to CRC and GC susceptibility.

Vitamin D receptor gene polymorphisms and the risk of colorectal cancer in a Chinese population.

OBJECTIVE: The purpose was to investigate single nucleotide polymorphism of the vitamin D receptor gene and its possible relationship with colorectal cancer (CRC) in a Chinese population. METHODS: The vitamin D receptor (VDR) genotypes were determined by polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) using endonuclease BsmI and FokI, and direct sequencing in 400 Chinese people, comprised of 200 CRC patients and 200 controls from the same area in China. RESULTS: The distribution of alleles (F/f) and genotypes (FF/Ff/ff) of the FokI had no significant difference between CRC patients and normal controls (P > 0.05), while that of the B allele and the BB genotype of the BsmI in CRC patients was significantly lower compared with the control group (0.1625 versus 0.740, P < 0.05, OR = 0.068, 95% CI: 0.048-0.096 and 0.060 versus 0.590, P < 0.05, OR = 0.015, 95% CI: 0.007-0.032). CONCLUSION: The BB genotype of the VDR BsmI variant was significantly associated with a decreased risk of CRC in a Chinese population, while the VDR FokI polymorphism was not significantly associated with it.

[Association of interleukin-1B gene polymorphisms with coronary heart disease].

OBJECTIVE: To determine whether polymorphisms in interleukin-1B gene promoter -31 and exon 5 +3953 loci are associated with coronary heart diseases (CHD) in Chengdu Han population. METHODS: Two SNPs of IL-1B gene (+3953C/T and -31T/C) in 100 patients with CHD (CHD group) and 144 healthy controls in Chengdu were analysed using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). RESULTS: Two genotypes at IL-1B + 3953 locus (CC and CT) and 3 genotypes at IL-1B -31 locus (CC, TC and TT) were identified. The -31T alleles carriers were associated with a significantly increased risk of CHD as compared with the non-carriers (OR = 2.12, 95% CI: 1.45-3.09, P < 0.01). Genotypes and allele frequencies at IL-1B + 3953 locus in CHD cases did not differ from the controls. CONCLUSION: IL-1B -31T/C polymorphism may contribute to the risk of developing CHD in Chengdu Han population.

[Genetic polymorphism of NFKB1 gene in Chinese Han of Chengdu and Thai populations].

OBJECTIVE: To investigate the single nucleotide polymorphisms (rs3774963 C>G and rs11722146 A>G) of NFKB1 gene between the Chinese Han of Chengdu and Thai populations, and simultaneously to compare distributions of genotype and allelic frequencies of NFKB1 among different ethnic groups from the International Haplotype Map Project. METHODS: The genotypes and allele frequencies of NFKB1 gene rs3774963 C>G and rs11722146 A>G were analyzed in 118 healthy Chinese Han of Chengdu and 101 Thai individuals using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) strategy and DNA sequencing. RESULTS: The frequencies of the CC, CG, and GG genotypes of rs3774963 C>G were 15.3%, 43.2%, and 41.5% in Chinese Han of Chengdu, and 25.7%, 47.5%, and 26.7% in Thai population, respectively. The frequencies of the C and G alleles were 36.9% and 63.1% in Chinese Han of Chengdu, and 49.5% and 50.5% in Thai population, respectively. There were significant differences in the genotypes and allele frequencies between the two groups. The frequencies of the AA, AG, and GG genotypes of rs11722146 A>G were 22.9%, 50.0%, and 27.1% in Chinese Han of Chengdu, and 18.8%, 53.5%, and 27.7% in Thai population, respectively. The frequencies of the A and G alleles were 47.9%, 52.1% in Chinese Hen of Chengdu, and 54.5%, 45.5% in Thai population, respectively. However, no statistically significant difference was observed between the two populations. Interestingly, when compared with the data from the International Haplotype Map Project, the genotypes and allele frequencies of NFKB1 gene rs11722146 A>G but not rs3774963 C>G in the Chinese Han of Chengdu were significantly different from those among European and Sub-Saharan African populations. CONCLUSION: NFKB1 gene polymorphism in diverse populations is significantly different.

Circular Ribonucleic Acid Expression Profile in Mouse Cortex after Traumatic Brain Injury.

Traumatic brain injury (TBI) causes high rates of worldwide death and morbidity because of the complex secondary injury cascade. Circular ribonucleic acid (RNA) (circRNA), a type of RNA that forms a covalently closed continuous loop, may be involved in the regulation of secondary injury because it is expressed widely in the brain and contributes to a large class of post-transcriptional regulators. Deep RNA sequencing (RNA-seq) and bioinformatic analysis were performed to investigate the expression profile and function of circRNAs in the mouse cortex after controlled cortical impact (CCI). A total of 19,794 circRNAs were identified, and 1315 were annotated in circBase. There were 191 filtered differentially expressed circRNAs (98 for up-regulated and 93 for down-regulated). The gene ontology and Kyoto Encyclopedia of Genes and Genomes analyses indicated that inflammation, cell death, and repair of damage were the main biological processes and molecular mechanisms related to altered circRNAs. The pathway-circRNA interaction network revealed three core circRNAs and five corepathways related to TBI. The circRNA-messenger RNA (mRNA) interaction network and competitive endogenous RNA (ceRNA) analysis suggested potential microRNA (miRNA) sponges and target mRNAs. In addition to five optimal circRNA-miRNA-mRNA pairs were analyzed, circRNA_16895-miRNA myosin-10 (Myo 10) was predicted to regulate fragment crystallizable gamma receptors (FcγR)-mediated phagocytosis pathway. Four circRNAs were selected for quantitative real-time polymerase chain reaction analysis to validate the sequencing data. Our results provide promising functions of circRNAs aberrantly expressed in TBI to explore molecular mechanisms and potential therapeutic targets for its therapy.

R497K polymorphism in epidermal growth factor receptor gene is associated with the risk of acute coronary syndrome.

BACKGROUND: Previous studies suggested that genetic polymorphisms in the epidermal growth factor receptor (EGFR) gene had been implicated in the susceptibility to some tumors and inflammatory diseases. EGFR has been recently implicated in vascular pathophysiological processes associated with excessive remodeling and atherosclerosis. Acute coronary syndrome (ACS) is a clinical manifestation of preceding atherosclerosis. Our purpose was to investigate the association of the EGFR polymorphism with the risk of ACS. In this context, we analyzed the HER-1 R497K and EGFR intron 1 (CA)n repeat polymorphisms in 191 patients with ACS and 210 age- and sex-matched controls in a Chinese population, using a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) strategy and direct sequencing. RESULTS: There were significant differences in the genotype and allele distribution of R497K polymorphism of the EGFR gene between cases and controls. The Lys allele had a significantly increased risk of ACS compared with the Arg allele (adjusted OR = 1.49, 95% CI: 1.12-1.98, adjusted P = 0.006). However, no significant relationship between the number of (CA)n repeats of EGFR intron 1 (both alleles < 20 or any allele > or = 20) and the risk of ACS was observed (adjusted OR = 0.97, 95% CI: 0.58-1.64, adjusted P = 0.911). Considering these two polymorphisms together, there was no statistically significant difference between the two groups. CONCLUSION: R497K polymorphism of the EGFR gene is significantly associated with the risk of ACS. Our data suggests that R497K polymorphism may be used as a genetic susceptibility marker of the ACS.

Genetic variation in interleukin-10 gene and risk of oral cancer.

BACKGROUND: Common genetic variants in immune and inflammatory response genes can affect the risk of developing oral cancer. Interleukin-10 (IL-10) is an immunosuppressive cytokine which may facilitate development of cancer by supporting tumor escape from the immune response. Inter-individual variations in IL-10 production were genetically contributed to polymorphisms within IL-10 promoter region. We determined whether single nucleotide polymorphisms (SNPs) at positions -1082 A/G (rs1800870), -819 T/C (rs1800871) and -592 A/C (rs1800872) in the IL-10 gene promoter were involved in predisposing an individual to oral cancer. METHODS: We analyzed 3 SNPS of IL-10 gene promoter in 280 patients with oral cancer and 300 age and sex matched controls in a Chinese population, using a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) strategy. RESULTS: There were significant differences in the genotype and allele distribution of -1082 A/G (rs1800870) polymorphism of the IL-10 gene among cases and controls. The -1082 G alleles carriers were associated with a significantly increased risk of oral cancer compared with the non-carriers (OR=1.821, 95% CI, 1.329-2.496, P<0.001). Haplotype analysis revealed that the GCC haplotype (defined by SNPs at positions -1082, -819 and -592) of IL-10 gene conveys the highest risk for oral cancer compared with the ATA haplotype (OR=1.716; 95% CI, 1.230-2.395; P=0.001). CONCLUSION: IL-10 gene promoter -1082 A/G (rs1800870) polymorphism, and its haplotype are significantly associated with the risk of oral cancer. Our data suggests that IL-10 gene plays an important role in the development of oral cancer.

[Study on genetic polymorphisms of P-selectins in Chinese Han of Chengdu and Thai populations].

OBJECTIVE: To study the gene polymorphisms of position --2123 C/G,--1969 G/A,--1817 T/C in promoter region and of Thr715Pro in exon thirteenth of P-selectin in the Chinese Han of Chengdu and Thai populations, and simultaneously to compare distributions of genotype and allelic frequencies of P-selectins among different races. Methods The genotypes and allele frequencies of the P-selectin base --2123 C/G,--1969 G/A,-1817 T/C and amino acid Thr715Pro were detected by polymerase chain reaction -restriction fragment length polymorphism (PCR-RFLP) to 120 healthy Chinese Han of Chengdu and 110 Thai population. RESULTS: There were no significant differences in the genotype and allele distribution of--2123 C/G,--1969 G/A,--1817 T/C polymorphisms for the P-selectin gene between Chinese Han of Chengdu and Thai populations (P > 0.05), in which compared with England and American, the distribution of P-selectin genotype and allele had significantly differences among ethnics (P < 0.001). No polymorphism of Thr715Pro was found in this study. Conclusion In Chinese Han of Chengdu and Thai populations the polymorphisms exist at base position--2123 C/G,--1969 G/A and --1817 T/C in promoter region of P-selectin. There are no significant differences in the genotype and allele distribution of the P-selectin gene polymorphisms between Chinese Han of Chengdu and Thai populations, but significantly different distribution of P-selectin gene polymorphisms occur among ethnics.

Pri-miR-34b/c rs4938723 polymorphism is associated with a decreased risk of gastric cancer.

Previous studies have demonstrated that miR-34 family members are abnormally expressed in gastric cancer. Overexpression of the miR-34 family suppresses gastric carcinogenesis, whereas downregulation of the miR-34 family promotes tumorigenesis. p53 can bind to the promoter region of miR-34b/c, leading to an increase of miR-34b/c expression. Recently, a variant in the promoter region of pri-miR-34b/c (rs4938723) has been discovered, with the function of altering the binding efficiency of transcription factor GATA. The purpose of this study was to examine the role of the miR-34b/c rs4938723 and TP53 Arg72Pro polymorphisms in the susceptibility of gastric cancer. We analyzed the distribution of the two polymorphisms in 197 patients with gastric cancer and 289 age-, gender-, ethnicity-, and living area-matched controls using polymerase chain reaction-restriction fragment length polymorphism and DNA direct sequencing. We found that the CT and CT/CC genotypes of the miR-34b/c rs4938723 were associated with a significantly decreased risk of gastric cancer compared with the TT genotype (CT vs. TT: odds ratio [OR]=0.66; 95% confidence interval [95% CI], 0.45-0.97; and CT/CC vs. TT: OR=0.67; 95% CI, 0.47-0.97, respectively). Combined analysis showed that subjects carrying the miR-34b/c rs4938723 CT/CC and TP53 CG/CC genotypes had a 0.62-fold decreased risk to develop gastric cancer compared with subjects carrying the miR-34b/c rs4938723 TT and TP53 CG/CC genotypes (OR=0.62; 95% CI, 0.40-0.96). These findings suggest that the miR-34b/c rs4938723 may individually and jointly have a protective effect on the risk of gastric risk.