Yi Chi Chen

Genetic association studies of angiogenesis- and vasoconstriction-related genes in women with recurrent pregnancy loss: a systematic review and meta-analysis

BACKGROUNDnAngiogenesis and an adequate blood supply are critical for several steps in human early pregnancy. Some studies have reported angiogenesis- and vasoconstriction-related genes are associated with recurrent pregnancy loss (RPL), but their sample size was limited. This study was conducted to investigate the genetic association between these angiogenesis- and vasoconstriction-related genes and idiopathic RPL, using meta-analyses.nnnMETHODSnA systematic review of the published literature from MEDLINE and EMBASE databases was conducted and investigations of an angiogenesis- and vasoconstriction-related gene polymorphism in RPL reported more than three times were selected. Aggregating data from eligible studies were integrated into meta-analyses by means of random effects models.nnnRESULTSnOf 185 potentially relevant studies, 18 case-control studies comprising a total of 2397 RPL patients and 1760 controls were included into the meta-analyses. Among these genetic association studies were 4 reports of vascular endothelial growth factor (VEGF) (-1154G>A) polymorphisms, 4 reports of p53 (codon72) and 10 reports of endothelial nitric oxide synthase (eNOS) (B/A, Glu298Asp) with RPL. The integrated results showed that VEGF (-1154G>A), p53 (codon 72) and eNOS (Glu298Asp) polymorphisms were significantly associated with RPL, and their summary odd ratios [95% confidence interval (CI)] were 1.51 (1.13-2.03), 1.84(1.07-3.16) and 1.37 (1.11-1.69), respectively. The summary odd ratio of the eNOS (B/A) polymorphism in RPL was 1.15 (0.94-1.41), and failed to show significance at meta-analysis.nnnCONCLUSIONSnMeta-analyses of available data showed significant associations between the VEGF (-1154G>A), p53 (codon72) and eNOS (Glu298Asp) polymorphisms and idiopathic RPL. These angiogenesis- and vasoconstriction-related genes jointly confer higher susceptibility to idiopathic RPL.

Association of polymorphisms/haplotypes of the genes encoding vascular endothelial growth factor and its KDR receptor with recurrent pregnancy loss

BACKGROUND Vascular endothelial growth factor (VEGF) and its kinase insert domain receptor (KDR) play an important role in angiogenesis, and their gene expression patterns also suggest a close relationship with early pregnancy. However, limited information is available regarding the role of the VEGF system, especially its KDR receptor, in recurrent pregnancy loss (RPL). This study was conducted to investigate a genetic association between VEGF and its receptor gene (KDR) with idiopathic RPL. METHODS In this case-control study, 115 women who had experienced at least two consecutive spontaneous miscarriages (n= 62 women with two miscarriages, n= 53 with three or more) and 170 controls were included. A total of 14 tag single-nucleotide polymorphisms (SNPs) of VEGF and KDR were selected from the HapMap Web site and three functional SNPs [rs1570360 (-1154G/A) of VEGF; rs2305948 (V297I) and rs1870377 (Q472H) of the KDR gene] were genotyped using primer extension analysis. We further used multifactor dimensionality reduction analysis to evaluate gene-gene interactions. RESULTS One tag SNP (rs6838752) and the functional SNP (Q472H) of the KDR gene were in complete linkage and showed significant differences between patients and controls (P< 0.05). The frequencies of haplotypes of VEGF (A-T-G haplotype) and KDR (A-C-A-T-G haplotype) showed significant differences in patients versus controls (P< 0.05). All comparisons with controls remained significant when the subgroup of women with three or more miscarriages was analyzed. CONCLUSIONS VEGF and its receptor gene (KDR) are associated with idiopathic RPL. The VEGF/KDR system jointly contributes to recurrent miscarriage in Taiwanese Han women.

Genetic association studies of ACE and PAI-1 genes in women with recurrent pregnancy loss: a systematic review and meta-analysis.

A fine balance between coagulation and fibrinolysis is critical in early pregnancy. Plasminogen activator inhibitor-1 (PAI-1) and angiotensin converting enzyme (ACE) are involved in the fibrinolytic process, and several studies have reported the association between their gene polymorphisms and recurrent pregnancy loss (RPL). This study was conducted to investigate the association between PAI-1 and ACE polymorphisms and idiopathic RPL, using meta-analyses. A systematic review of the published literature from the MEDLINE and EMBASE databases before April 2012 was conducted. Of 209 potentially relevant studies, 22 case-control studies comprising a total of 2,820 RPL patients and 3,009 controls were included. Among these studies were 11 reports of PAI-1 4G/5G and 11 of ACE I/D polymorphisms in patients with RPL. A significant association was found withthe ACE I/D polymorphism [summary odds ratio 1.29 (95% confidence interval 1.02-1.62)] in studies including more than two recurrent abortions. Subgroup analysis did not show significant associations with RPL in Caucasian and non-Caucasian patients. Meta-analyses of PAI-1 4G/5G polymorphism were not found associations with RPL in studies including more than two or three recurrent abortions, and in studies of Caucasian and non-Caucasian patients. In conclusion, meta-analyses showed a significant association between the ACE I/D polymorphism and idiopathic RPL. High clinical heterogeneity existed among studies of PAI-1 4G/5G, and the aggregated data failed to confer higher susceptibility to idiopathic RPL. More well-designed studies with different ethnic populations are required for future integration.

Polymorphisms of endocrine gland-derived vascular endothelial growth factor gene and its receptor genes are associated with recurrent pregnancy loss

BACKGROUNDnEndocrine gland-derived vascular endothelial growth factor (EG-VEGF) and its receptor genes [prokineticin receptor 1 (PKR1) and prokineticin receptor 2 (PKR2)] have been identified in the last decade and their expression is restricted to the steroidogenic glands (ovary, testis, adrenal gland and placenta). Their expression patterns also suggest a close relationship to early pregnancy. However, little information is available regarding the role of EG-VEGF and its receptors (PKR1 and PKR2) in recurrent pregnancy loss (RPL). This study was conducted to investigate the association between polymorphisms of EG-VEGF and its receptor genes (PKR1 and PKR2) and idiopathic RPL.nnnMETHODSnIn this case-control study, 115 women with a history of idiopathic RPL and 170 controls were included. A total of 11 tag single nucleotide polymorphisms (SNPs) selected from EG-VEGF, PKR1 and PKR2 were genotyped. We further used multifactor dimensionality reduction (MDR) analysis to choose a best model and evaluate gene-gene interactions.nnnRESULTSnTwo tag SNPs of PKR1 (rs4627609, rs6731838) and one tag SNP of PKR2 (rs6053283) were significantly associated with idiopathic RPL (P < 0.05). The frequencies of haplotypes C-G and T-A of PKR1 and haplotype A-G-C-G-G of PKR2 were significantly increased in women with idiopathic RPL (P < 0.05); MDR tests revealed gene-gene interactions between three loci [EG-VEGF (rs7513898), PKR1(rs6731838), PKR2(rs6053283)] based on the association model (P = 0.008). The adjusted odds ratio of high- and low-risk genotype combinations in the three-locus model was 3.94 (95% confidence interval: 2.38-6.52).nnnCONCLUSIONSnEG-VEGF receptor (PKR1, PKR2) gene polymorphisms and haplotypes were associated with idiopathic RPL. These three genes (EG-VEGF, PKR1 and PRK2) jointly contribute to RPL in the Taiwanese Han population.

Association of progesterone receptor polymorphism with idiopathic recurrent pregnancy loss in Taiwanese Han population

PurposeRecurrent pregnancy loss (RPL) could be caused by insufficient progesterone in the luteal phase of menstruation and early pregnancy. Progesterone plays a critical role in oocyte maturation, embryo implantation and placenta maintenance in early gestation. This study was set out to investigate the association between polymorphisms of the progesterone receptor (PGR) gene and idiopathic RPL.MethodsOne hundred twenty-one women with a history of idiopathic recurrent pregnancy loss (RPL) and 179 control subjects were enrolled into the study. Six tag SNPs and two functional SNPs [PROGINS (rs1042838), +331xa0C/T (rs10895068)] of the progesterone receptor gene were genotyped.ResultsWe found that the allele and genotype frequencies of the functional SNP [PROGINS (rs1042838)] were both significantly higher in patients with idiopathic RPL than in the control subjects (both P valuesu2009=u20090.006). In addition, the C-C haplotype, which consists of rs590688Cu2009>u2009G and rs11224592Tu2009>u2009C, is associated with a decreased risk of RPL (pu2009=u20090.004).ConclusionPROGINS polymorphism confers susceptibility to idiopathic recurrent pregnancy loss in Taiwanese Han women.

Association of sex hormone receptor gene polymorphisms with recurrent pregnancy loss: a systematic review and meta-analysis

OBJECTIVEnTo investigate the genetic association between estrogen and progesterone receptor polymorphisms (ER, PR) and skewed X chromosome inactivation (XCI) and idiopathic recurrent pregnancy loss (RPL).nnnDESIGNnA systematic review and meta-analysis using electronic database (MEDLINE and EMBASE) up to April 2011.nnnSETTINGn24 eligible studies from 14 countries.nnnPATIENT(S)n2,750 RPL patients and 3,123 controls were included.nnnINTERVENTION(S)nMeta-analyses by means of random-effects models.nnnMAIN OUTCOME MEASUREMENT(S)nCommon polymorphisms of ER and PR and skewed XCI.nnnRESULT(S)nOf 221 potentially relevant studies, 24 case-control studies were included: 6 reports of PR polymorphisms (PROGINS), 6 reports of ER-α (3 each of rs2234693 [PvuII], rs9340799 [XbaI], and B domain) and 12 reports of skewed XCI. The integrated result showed that women with skewed XCI (>90%) had a higher risk for RPL (the summary OR [95% CI]: 2.43 [1.34-4.43]), and the subgroup analysis of those studies that included more than three consecutive miscarriages (5 studies), also showed a significant association with RPL (2.52 [1.16-5.44]). Among studies of PR (PROGINS) and ER (PuvII, XbaI, B domain) polymorphisms in RPL, the summary ORs were 1.46 (0.56-3.79), 0.90 (0.47-1.75), 0.83 (0.53-1.29), and 1.07 (0.43-2.63), respectively.nnnCONCLUSION(S)nMeta-analyses of the available data showed a significant association between skewed XCI and idiopathic RPL. More data on the associations between ER and PR polymorphisms and RPL would be helpful to elucidate their roles in RPL.

Gene-gene interactions and gene polymorphisms of VEGFA and EG-VEGF gene systems in recurrent pregnancy loss

PurposeBoth vascular endothelial growth factor A (VEGFA) and endocrine gland-derived vascular endothelial growth factor (EG-VEGF) systems play major roles in angiogenesis. A body of evidence suggests VEGFs regulate critical processes during pregnancy and have been associated with recurrent pregnancy loss (RPL). However, little information is available regarding the interaction of these two major major angiogenesis-related systems in early human pregnancy. This study was conducted to investigate the association of gene polymorphisms and gene-gene interaction among genes in VEGFA and EG-VEGF systems and idiopathic RPL.MethodsA total of 98 women with history of idiopathic RPL and 142 controls were included, and 5 functional SNPs selected from VEGFA, KDR, EG-VEGF (PROK1), PROKR1 and PROKR2 were genotyped. We used multifactor dimensionality reduction (MDR) analysis to choose a best model and evaluate gene-gene interactions. Ingenuity pathways analysis (IPA) was introduced to explore possible complex interactions.ResultsTwo receptor gene polymorphisms [KDR (Q472H) and PROKR2 (V331M)] were significantly associated with idiopathic RPL (Pu2009<u20090.01). The MDR test revealed that the KDR (Q472H) polymorphism was the best loci to be associated with RPL (Pu2009=u20090.02). IPA revealed EG-VEGF and VEGFA systems shared several canonical signaling pathways that may contribute to gene-gene interactions, including the Akt, IL-8, EGFR, MAPK, SRC, VHL, HIF-1A and STAT3 signaling pathways.ConclusionTwo receptor gene polymorphisms [KDR (Q472H) and PROKR2 (V331M)] were significantly associated with idiopathic RPL. EG-VEGF and VEGFA systems shared several canonical signaling pathways that may contribute to gene-gene interactions, including the Akt, IL-8, EGFR, MAPK, SRC, VHL, HIF-1A and STAT3.

miR‐346 and miR‐582‐3p‐regulated EG‐VEGF expression and trophoblast invasion via matrix metalloproteinases 2 and 9

Endocrine gland-derived vascular endothelial growth factor (EG-VEGF) is an important regulator for embryo implantation and placental development, and is clinically associated with several obstetric disorders related to insufficient or inappropriate trophoblast invasion, such as recurrent abortion, preeclampsia, and intrauterine fetal growth restriction. This study was performed to identify the microRNAs targeting EG-VEGF, and evaluate the regulatory effect on trophoblast biology. miR-346 and miR-582-3p were initially identified via bioinformatic tools, and their specific binding sites on the EG-VEGF 3UTR were further confirmed using dual luciferase and a co-transfection assays. miR-346 and miR-582-3p were demonstrated not only to suppress EG-VEGF expression, but also inhibit trophoblast invasion and migration in the JAR and HTR-8/SVneo cell lines. We further evaluated the effect of microRNAs in HTR-8/SVneo cells coexpressing EG-VEGF and miR-346 or miR-582-3p on matrix metalloproteinase (MMP 2 and MMP 9) and the tissue inhibitors of metalloproteinase (TIMP 1 and TIMP 2) using RT-PCR, western blotting and gelatin zymography. TIMP 1 and TIMP 2 were not affected by the two microRNAs, whereas the expressions and activities of MMP 2 and MMP 9 were significantly downregulated, which in turn inhibited the invasion ability of trophoblasts. In conclusion, miR-346 and miR-582-3p regulate EG-VEGF-induced trophoblast invasion through repressing MMP 2 and MMP 9, and may become novel diagnostic biomarkers or therapeutic targets for EG-VEGF-related obstetric disorders.

Gene-gene interactions and risk of recurrent miscarriages in carriers of endocrine gland-derived vascular endothelial growth factor and prokineticin receptor polymorphisms

OBJECTIVEnTo study endocrine gland-derived vascular endothelial growth factor (EG-VEGF), prokineticin receptor (PROKR) 1, and PROKR2 variants in the coding regions of idiopathic recurrent miscarriage (RM) patients and further evaluate gene-gene interactions of these three genes.nnnDESIGNnCase-control study.nnnSETTINGnUniversity-based reproductive clinics and genetics laboratory.nnnPATIENT(S)nA total of 142 women with a history of idiopathic RM and 149 control subjects were included.nnnINTERVENTION(S)nNone.nnnMAIN OUTCOME MEASURE(S)nAll blood samples were nucleotide sequenced in the coding regions of EG-VEGF, PROKR1, and PROKR2. Gene-gene interaction of three gene variants was evaluated with the use of the multifactor dimensionality reduction method.nnnRESULT(S)nOne nonsynonymous variant of each of the three genes was identified, and PROKR1 (I379V) and PROKR2 (V331M) were significantly associated with idiopathic RM. Genetic interactions were found not only between PROKR1 (I379V) and PROKR2 (V331M), but also among EG-VEGF (V67I), PROKR1 (I379V), and PROKR2 (V331M). Women carrying low-risk genotypes had a 77% reduced risk of experiencing miscarriages compared with those carrying high-risk genotypes.nnnCONCLUSION(S)nThe present study corroborates the clinical relevance of the EG-VEGF system in human early pregnancy, and provides evidence for the gene-gene interactions of EG-VEGF and PROKR variants.

Prokineticin receptor variants (PKR1-I379V and PKR2-V331M) are protective genotypes in human early pregnancy

Endocrine gland-derived vascular endothelial growth factor (EG-VEGF) and its receptor genes (PROKR1 (PKR1) and PROKR2 (PKR2)) play an important role in human early pregnancy. We have previously shown that PROKR1 and PROKR2 are associated with recurrent miscarriage (RM) using the tag-SNP method. In this study, we aimed to identify PROKR1 and PROKR2 variants in idiopathic RM patients by genotyping of the entire coding regions. Peripheral blood DNA samples of 100 RM women and 100 controls were subjected to sequence the entire exons of PROKR1 and PROKR2. Significant non-synonymous variant genotypes present in the original 200 samples were further confirmed in the extended samples of 144 RM patients and 153 controls. Genetic variants that were over- or under-represented in the patients were ectopically expressed in HEK293 and JAR cells to investigate their effects on intracellular calcium influx, cell proliferation, cell invasion, cell-cell adhesion, and tube organization. We found that the allele and genotype frequencies of PROKR1 (I379V) and PROKR2 (V331M) were significantly increased in the normal control groups compared with idiopathic RM women (P<0.05). PROKR1 (I379V) and PROKR2 (V331M) decreased intracellular calcium influx but increased cell invasiveness (P<0.05), whereas cell proliferation, cell-cell adhesion, and tube organization were not significantly affected. In conclusion, PROKR1 (I379V) and PROKR2 (V331M) variants conferred lower risk for RM and may play protective roles in early pregnancy by altering calcium signaling and facilitating cell invasiveness.