Mei Tsz Su

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

BACKGROUND Angiogenesis 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. METHODS A 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. RESULTS Of 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. CONCLUSIONS Meta-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.

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.

Quantitative trait analysis suggests polymorphisms of estrogen-related genes regulate human sperm concentrations and motility

BACKGROUND Human spermatogenesis is regulated by complex networks, and estrogens are recognized as one of the significant regulators of spermatogenesis. We tested the associations between variants of estrogen-related genes and semen parameters. METHODS We performed genotyping for genetic variants of estrogen-related genes and quantitative trait analysis of fertile and infertile men with well-characterized reproductive phenotypes. Men with known semen parameters (n= 677) were enrolled, including 210 fertile men and 467 infertile men. A total of 17 genetic markers from 10 genes, including 2 estrogen receptors (ER-α, ER-β), 7 estrogen synthesizing/metabolizing genes (CYP19A1, HSD17B1, CYP1A1, CYP1B1, COMT, GSTM1, GSTT1) and 1 transport gene (SHBG) were genotyped. Sperm concentration, motility and morphology were taken as quantitative traits to correlate with genetic variants in the estrogen-related genes. RESULTS Five genes (rs1801132 and rs2228480 of the ER-α gene, rs1256049 and rs4986938 of the ER-β gene, rs605059 of the HSD17B1 gene, rs1799941 of the SHBG gene and rs1048943 and rs4646903 of the CYP1A1 gene) were found to be significantly associated with sperm concentration (P< 0.01), while five genes (rs1801132 of the ER-a gene, rs1256049 of the ER-β gene, rs1048943 of the CYP1A1 gene, rs605059 of the HSD17B1 gene and rs1799941 along with rs6259 of the SHBG gene) were associated with sperm motility (P< 0.01). None of the estrogen-related genes were associated with sperm morphology. With an increasing number of risk alleles, sperm concentration and motility tended to deteriorate and show a loci-dosage effect. CONCLUSIONS Quantitative trait analysis based on a limited number of genetic markers suggests that estrogen-related genes mainly regulate sperm concentration and motility.

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

OBJECTIVE To investigate the genetic association between estrogen and progesterone receptor polymorphisms (ER, PR) and skewed X chromosome inactivation (XCI) and idiopathic recurrent pregnancy loss (RPL). DESIGN A systematic review and meta-analysis using electronic database (MEDLINE and EMBASE) up to April 2011. SETTING 24 eligible studies from 14 countries. PATIENT(S) 2,750 RPL patients and 3,123 controls were included. INTERVENTION(S) Meta-analyses by means of random-effects models. MAIN OUTCOME MEASUREMENT(S) Common polymorphisms of ER and PR and skewed XCI. RESULT(S) Of 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. CONCLUSION(S) Meta-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 (P < 0.01). The MDR test revealed that the KDR (Q472H) polymorphism was the best loci to be associated with RPL (P = 0.02). 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.

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

OBJECTIVE To 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. DESIGN Case-control study. SETTING University-based reproductive clinics and genetics laboratory. PATIENT(S) A total of 142 women with a history of idiopathic RM and 149 control subjects were included. INTERVENTION(S) None. MAIN OUTCOME MEASURE(S) All 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. RESULT(S) One 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. CONCLUSION(S) The 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.

Primary Cilium-Regulated EG-VEGF Signaling Facilitates Trophoblast Invasion

Trophoblast invasion is an important event in embryo implantation and placental development. During these processes, endocrine gland‐derived vascular endothelial growth factor (EG‐VEGF) is the key regulator mediating the crosstalk at the feto‐maternal interface. The primary cilium is a cellular antenna receiving environmental signals and is crucial for proper development. However, little is known regarding the role of the primary cilium in early human pregnancy. Here, we demonstrate that EG‐VEGF regulates trophoblast cell invasion via primary cilia. We found that EG‐VEGF activated ERK1/2 signaling and subsequent upregulation of MMP2 and MMP9, thereby facilitating cell invasion in human trophoblast HTR‐8/SVneo cells. Inhibition of ERK1/2 alleviated the expression of MMPs and trophoblast cell invasion after EG‐VEGF treatment. In addition, primary cilia were observed in all the trophoblast cell lines tested and, more importantly, in human first‐trimester placental tissue. The receptor of EG‐VEGF, PROKR1, was detected in primary cilia. Depletion of IFT88, the intraflagellar transporter required for ciliogenesis, inhibited primary cilium growth, thereby ameliorating ERK1/2 activation, MMP upregulation, and trophoblast cell invasion promoted by EG‐VEGF. These findings demonstrate a novel function of primary cilia in controlling EG‐VEGF‐regulated trophoblast invasion and reveal the underlying molecular mechanism. J. Cell. Physiol. 232: 1467–1477, 2017.

A Common Variant of PROK1 (V67I) Acts as a Genetic Modifier in Early Human Pregnancy through Down-Regulation of Gene Expression

PROK1-V67I has been shown to play a role as a modifier gene in the PROK1-PROKR system of human early pregnancy. To explore the related modifier mechanism of PROK1-V67I, we carried out a comparison study at the gene expression level and the cell function alternation of V67I, and its wild-type (WT), in transiently-transfected cells. We, respectively, performed quantitative RT-PCR and ELISA assays to evaluate the protein and/or transcript level of V67I and WT in HTR-8/SV neo, JAR, Ishikawa, and HEK293 cells. Transiently V67I- or WT-transfected HTR-8/SV neo and HEK293 cells were used to investigate cell function alternations. The transcript and protein expressions were down-regulated in all cell lines, ranging from 20% to 70%, compared with WT. There were no significant differences in the ligand activities of V67I and WT with regard to cell proliferation, cell invasion, calcium influx, and tubal formation. Both PROK1 alleles promoted cell invasion and intracellular calcium mobilization, whereas they had no significant effects on cell proliferation and tubal formation. In conclusion, the biological effects of PROK1-V67I on cell functions are similar to those of WT, and the common variant of V67I may act as a modifier in the PROK1-PROKR system through down-regulation of PROK1 expression. This study may provide a general mechanism that the common variant of V67I, modifying the disease severity of PROK1-related pathophysiologies.

Partial trisomy of chromosome 21 without the Down syndrome phenotype

Department of Obstetrics and Gynecology, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan Department of Obstetrics and Gynecology, Kuo General Hospital, Tainan, Taiwan Department of Pediatrics, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan *Correspondence to: Pao-Lin Kuo. E-mail: paolink@mail.ncku.edu.tw; Tsung-Cheng Kuo. E-mail: tckuo@kgh.com.tw These authors made an equal contribution to this work.