Circulating Levels of Pregnancy-Associated, Placenta-Specific microRNAs in Pregnant Women With Placental Abruption.

The aim of this study was to clarify the association between circulating pregnancy-associated, placenta-specific microRNAs (miRNAs) in maternal plasma and placental abruption. All samples were obtained after receiving written informed consent, and the study protocol was approved by the institutional review board. Maternal blood samples (7 mL) were obtained at 25 to 40 weeks of gestation from 15 cases of placental abruption (placental abruption group) and from 24 cases of uncomplicated pregnancies (uncomplicated pregnancy group). The plasma concentrations of pregnancy-associated, placenta-specific miRNAs (miR-515-3p, -517a, -517c, and -518b) were measured by quantitative real-time reverse transcription-polymerase chain reaction. There were no significant differences in clinical characteristics between the 2 groups. The median concentration of plasma cell-free miR-517c in the placental abruption group was 21 672.2 copies/mL, whereas that in the uncomplicated pregnancy group was 13 452.0 copies/mL (Mann-Whitney U test, P = .047). Receiver operating characteristic curve analysis revealed that plasma cell-free miR-517c levels discriminated placental abruption from uncomplicated pregnancy with an area under the curve of 0.692. When a cutoff negative/positive value of 15 669.6 copies/mL was selected, the sensitivity and specificity were 73.3% and 62.5%, respectively. In addition, the positive and negative predictive values were 55.0% and 78.9%, respectively. Plasma cell-free miR-517a and miR-517c levels in the large abruption (degree of abruption ≥50% of placenta) group were significantly higher than in the small abruption (<50%) group ( P = .03 for both miRNAs). In conclusion, the circulating level of cell-free miR-517c in maternal plasma was increased as a consequence of placental abruption and may be a potential biomedical marker for placental abruption.

A significant association between rs8067378 at 17q12 and invasive cervical cancer originally identified by a genome-wide association study in Han Chinese is replicated in a Japanese population.

In this study, associations between invasive cervical cancer and four cervical cancer susceptibility loci (rs13117307 at 4q12, rs8067378 at 17q12, and rs4282438 and rs9277952 at 6p21.32) in the Han Chinese population were investigated in a Japanese population. Human leukocyte antigen (HLA)-DPB1 alleles were also investigated for their association with cervical cancer risk in the Japanese population. After receiving written informed consent, 214 unrelated Japanese women with invasive cervical cancer and 288 cancer-free Japanese women were recruited, and DNA samples were obtained (study protocol approved by Institutional Review Board of Nagasaki University). Of the four single-nucleotide polymorphisms, rs8067378 showed a significant association with invasive cervical cancer (P=0.0071). Under a recessive model, the minor allele G of rs8067378 contributed to the risk of invasive cervical cancer (odds ratio=2.92, 95% confidence interval=1.40-6.36; P=0.0021). No association was detected between HLA-DPB1 alleles and cervical cancer risk in the Japanese population. In conclusion, we show for the first time, to the best of our knowledge, that an association between increased risk of invasive cervical cancer and rs8067378 in the Han Chinese population is replicated in a Japanese population. In addition, Japanese women with the GG genotype of rs8067378 are a candidate high-risk group for invasive cervical carcinoma.

Circulating chromosome 19 miRNA cluster microRNAs in pregnant women with severe pre-eclampsia.

AIM: To clarify the association between circulating chromosome 19 miRNA cluster (C19MC) microRNAs in maternal plasma and severe pre-eclampsia. METHOD: Maternal blood samples (7 mL) at 27-34 weeks of gestation were obtained from 20 pregnant women with severe pre-eclampsia (sPE group) and from 20 uncomplicated pregnant women (NP group). Twenty cases of severe pre-eclampsia were classified into late onset (sPELO group; n = 14) and early onset (sPEEO group; n = 6). Plasma concentration of C19MC microRNAs (miR-518b, -1323, -516b, -516a-5p, -525-5p, -515-5p, -520 h, -520a-5p, -519d and -526b) was measured on quantitative real-time reverse transcription-polymerase chain reaction. RESULTS: The circulating levels of all 10 C19MC microRNAs in maternal plasma were significantly increased in the sPE group compared with the NP group. Plasma concentration of all 10 C19MC microRNAs tested was significantly increased in the sPEEO group compared with the NP group, while plasma concentration of nine miRNAs, except for miR-519d, was significantly increased in the sPELO group compared with the NP group. Of the 10 C19MC microRNAs measured, plasma concentration of eight miRNAs, except for miR-518b and miR-519d, was significantly increased in the sPEEO group compared with the sPELO group. CONCLUSIONS: Increased levels of C19MC microRNAs in maternal plasma are a characteristic phenomenon of established severe pre-eclampsia, and it has been shown for the first time that the upregulation of C19MC miRNAs occurred as a consequence of, not in advance of, the onset of pre-eclampsia.

Increased Levels of Cell-Free miR-517a and Decreased Levels of Cell-Free miR-518b in Maternal Plasma Samples From Placenta Previa Pregnancies at 32 Weeks of Gestation.

OBJECTIVE: The aim of this study was to clarify the association between placenta previa and circulating levels of cell-free pregnancy-associated placenta-specific microRNAs (miRNAs) in maternal plasma. METHOD: Twenty singleton pregnancies with placenta previa (placenta previa group) and 26 uncomplicated pregnancies (control group) were recruited. Blood sampling was performed at 32 weeks of gestation, and cesarean delivery in all cases of placenta previa was performed at a mean gestational age of 37 weeks. The maternal plasma concentrations of cell-free pregnancy-associated placenta-specific miRNAs (miR-517a and miR-518b) were measured by absolute quantitative real-time reverse transcription-polymerase chain reaction. RESULTS: Plasma concentrations of cell-free miR-517a were significantly higher in the placenta previa group than that in the control group (P = .011), while the plasma concentration of cell-free miR-518b was significantly lower in the placenta previa group than that in the control group (P = .004). Plasma concentrations of cell-free miR-517a in placenta previa were significantly higher in placenta previa with alert bleeding later group than those in placenta previa without alert bleeding group or control group (P = .030 or .047, respectively) and correlated with the volume of hemorrhage at delivery (R and P value: .512 and .025). CONCLUSION: Plasma concentrations of cell-free miR-517a and miR-518b at 32 weeks of gestation were altered in pregnant women with placenta previa, and the circulating level of cell-free miR-517a in placenta previa may be a predictive marker for the risks of alert bleeding later and massive hemorrhage at delivery.

Effect of labor on plasma concentrations and postpartum clearance of cell-free, pregnancy-associated, placenta-specific microRNAs.

OBJECTIVE: This study aimed to investigate the effect of labor on plasma concentrations of cell-free, pregnancy-associated, placenta-specific microRNAs (miRNAs) before and after delivery. METHOD: In the non-labor group (32 women), cesarean section (C/S) was performed before the beginning of labor. In the labor group (32 women), C/S was performed after the beginning of labor. Plasma concentrations of cell-free, pregnancy-associated, placenta-specific miRNAs (miR-515-3p, miR-517a, miR-517c, and miR-518b) were measured by real-time quantitative PCR. Each miRNA concentration was compared between the non-labor and labor groups. RESULTS: Before C/S, plasma concentrations of cell-free, pregnancy-associated, placenta-specific miRNAs in the labor group were significantly higher than those in the non-labor group (P = 0.001 for 515-3p, P = 0.002 for 517a, P = 0.001 for 517c, and P = 0.003 for 518b). Twenty-four hours after delivery, plasma concentrations of cell-free, pregnancy-associated, placenta-specific miRNAs in the labor group were significantly higher than those in the non-labor group (P = 0.002 for 515-3p, P = 0.017 for 517a, P = 0.043 for 517c, and P = 0.009 for 518b). CONCLUSION: The presence of labor affects cell-free, pregnancy-associated, placenta-specific miRNA levels in maternal plasma. Labor also affects postpartum clearance of these miRNAs 24 h after delivery.

Genome-wide association study of HPV-associated cervical cancer in Japanese women.

One of the important factors influencing the development of uterine cervical cancer is human papillomavirus infection in women. Usually, the infecting papillomavirus is eliminated from individuals; however, some retain the virus and this is believed to lead to the development of uterine cervical cancer. It is possible that virus elimination or persistent infection depends on an individual's genetic background. To identify single nucleotide polymorphisms associated with susceptibility to persistent infection or cervical cancer, a genome-wide association study was performed on 226 cases and 186 controls. Some of the single nucleotide polymorphisms showed a P-value < 10(-5); however, no polymorphisms that were significantly associated with susceptibility to cervical cancer were identified.

Identification of endometrioid endometrial carcinoma-associated microRNAs in tissue and plasma.

OBJECTIVE: This study aimed to identify a set of endometrioid endometrial carcinoma EEC-associated microRNAs (miRNAs) in tissue and plasma, and evaluate their clinical significance. METHODS: A set of EEC-associated miRNAs in tissue and plasma was identified by next-generation sequencing (NGS), which could enable in-depth characterization of the global repertoire of miRNAs. RESULTS: NGS identified 11 candidate EEC-associated miRNAs. Quantitative reverse-transcriptase PCR identified 8 EEC-associated miRNAs in tissue (upregulated: miR-499, miR-135b, miR-205, downregulated: miR-10b, miR-195, miR-30a-5p, miR-30a-3p and miR-21). Expression of hsa-miR-499 in International Federation of Gynecology and Obstetrics (FIGO) Stage IA and Grade 1 tissues was significantly lower than in others (FIGO Stage IB or more advanced, and Grade 2 or 3). By receiver operating characteristic (ROC) curve analysis, compared with single EEC-associated miRNA, two miRNA signatures (miR135b/miR195 and miR135b/miR30a-3p) could distinguish between EEC and normal endometrial tissue samples yielding a high area under the curve (AUC) of 0.9835 [95% confidence interval (CI): 0.9677-1.0], and 0.9898 (95% CI: 0.9677-1.0), respectively. As possible non-invasive markers for EEC, four EEC-associated miRNAs (increased level: miR-135b and miR-205, decreased-level: miR-30a-3p and miR-21) in plasma were identified. Circulating levels of three EEC-associated miRNAs (miR-135b, miR-205 and miR-30a-3p) in plasma were significantly decreased after hysterectomy. ROC curves analysis revealed that miR-135b and miR-205 levels in plasma yielded AUCs of 0.9722 (95% CI: 0.913-1.0) and 1.0 (95% CI: 1.0-1.0), respectively. CONCLUSION: Measurement of tissue and plasma EEC-associated miRNAs may be useful for early detection, diagnostic, and follow-up tests for EEC.

Single human papillomavirus 16 or 52 infection and later cytological findings in Japanese women with NILM or ASC-US.

The relationship between oncogenic human papillomavirus (HPV) infection and later cytological findings in the uterine cervix is unknown in women who were negative for intraepithelial lesion and malignancy (NILM) or atypical squamous cells of undetermined significance (ASC-US). This was investigated in this study in a Japanese population to determine the clinical utility of oncogenic (HPV) genotyping. The relative risk of progressive cytological findings 2 years after identification of oncogenic HPV infection was higher than in cases of non-oncogenic HPV infection (relative risk 3.827; 95% confidence interval (CI): 1.282-11.422), as well as in cases of negative HPV infection (relative risk 2.124; 95% CI: 1.451-3.110). Moreover, the relative risk of progression of cytological findings 2 years later in cases of HPV-16 infection was higher than in cases of HPV-52 infection (relative risk 2.094; 95% CI: 1.005-3.935). Therefore, the initial HPV-DNA genotype may be a potential predictive marker of later progression of cytological findings in the uterine cervix in cases of NILM or ASC-US.

Predominantly placenta-expressed mRNAs in maternal plasma as predictive markers for twin-twin transfusion syndrome.

OBJECTIVE: This study aimed to identify a set of predominantly placental (PP) mRNAs, which are associated with later-developing twin-to-twin transfusion syndrome (TTTS). METHOD: First, out of 50 PP mRNAs we previously reported, we select target mRNAs that are ordinarily detectable in maternal plasma. Plasma concentrations of these PP mRNAs were measured in monochorionic diamniotic twin (MCDA-T) pregnancies complicated by TTTS later (n = 11) and in uncomplicated MCDA-T pregnancies (n = 17). Finally, the diagnostic values of the PP mRNAs in plasma were evaluated. RESULTS: From 50 PP mRNAs, nine [human placental lactogen (hPL); pregnancy-specific glycoproteins 2 (PSG2); human pregnancy-specific glycoproteins 3 (PSG3); syncytin; syncytin 2; retinoic acid-induced 14; A disintegrin and metalloproteinase domain-containing protein 12 (ADAM12); chorionic glycoprotein hormones, alpha polypeptide; and chorionic glycoprotein hormones, and beta polypeptide] were selected as target mRNAs. Changes in six PP mRNAs [increased hPL, PSG2, and PSG3 and decreased syncytin, syncytin2, and ADAM12] in maternal plasma were detected in MCDA-T pregnant women who subsequently developed TTTS. Finally, mRNA signatures gave elevated AUCs (hPL/PSG2: 0.8717; hPL/PSG3: 0.8449; hPL/ADAM12: 0.8396) compared with single hPL mRNA. CONCLUSION: Quantitative aberration of plural cell-free PP mRNAs in maternal plasma precedes the appearance of clinically apparent TTTS. This suggests that pathophysiological changes in the placenta are associated with morbid conditions of TTTS.

Initial viral load in cases of single human papillomavirus 16 or 52 persistent infection is associated with progression of later cytopathological findings in the uterine cervix.

The aim of this study was to investigate the relationship between viral load in single human papillomavirus (HPV) 16 or 52 persistent infection and the progression of later cytopathological findings in the uterine cervix. Cervical cytology and HPV genotyping tests were repeated within 3-6 months in 305 women with oncogenic HPV. Twenty-four cases of single HPV 52 persistent infection and 24 cases of single HPV 16 persistent infection were identified. Cases with later cytopathological findings showing progression were defined as the progression group, while those with no change or regression were the non-progression group. Relative HPV DNA loads were determined by quantitative real-time polymerase chain reaction and expressed relative to human albumin (ALB) DNA. Differences between the two groups were evaluated. The median relative HPV 52 DNA load was 2.211 in the progression group and 0.022 in the non-progression group (Mann-Whitney U-test, P = 0.003). The median relative HPV 16 DNA load was 4.206 in the progression group and 0.103 in the non-progression group (P = 0.001). HPV 52 and 16 DNA loads assessed by quantitative real-time methods may be useful short-term markers for identifying women at high risk for progression of cervical cytological pathology.

Copy number variation of the antimicrobial-gene, defensin beta 4, is associated with susceptibility to cervical cancer.

The aim of this study was to investigate association between copy number variation of the defensin beta 4 gene (DEFB4) and susceptibility to cervical cancer in a population at high risk of persistent oncogenic human papillomavirus (HPV) infection. The study subjects comprised 204 women with cervical cancer, a population having a high risk of persistent oncogenic HPV infection (cervical cancer group), and 200 healthy women from the general population (control group). Copy number variation of DEFB4 in each test sample was determined by relative quantitation using the comparative CT ((ΔΔ)CT) method. Differences between the two groups were evaluated. The median DEFB4 copy number in the cervical cancer group was four and in the control group was five (P=2.77e-4, t-test). The odds ratio of cervical cancer in individuals with four DEFB4 copies or less was higher (odds ratio 2.02; 95% confidence interval odds ratio 1.36-3.02), compared with that in individuals with five or more copies (odds ratio 0.49; 95% confidence interval odds ratio 0.33-0.74). We found copy number variation of DEFB4 was a host genetic factor conferring susceptibility to cervical cancer. A lower DEFB4 copy number was associated with susceptibility to cervical cancer.

Characterization of placenta-specific microRNAs in fetal growth restriction pregnancy.

OBJECTIVE: The aim of this study was to characterize placenta-specific microRNAs in fetal growth restriction (FGR) pregnancy. METHOD: Placenta-specific miRNAs were identified by next-generation sequencing analysis. Subsequently, quantitative real-time reverse-transcription polymerase chain reaction was used to identify FGR placenta-specific miRNAs whose level of expression was significantly decreased in FGR placenta (n = 45) compared with uncomplicated placenta (n = 50). FGR pregnancy-associated, placenta-specific microRNAs were identified in maternal plasma after delivery at significantly decreased concentrations, and their circulating levels in maternal plasma was compared between FGR pregnancies (n = 10) and uncomplicated pregnancies (n = 10). RESULTS: Out of the ten placenta-specific microRNAs that we identified, seven placenta-specific microRNAs (hsa-miR-518b, hsa-miR-1323, hsa-miR-516b, hsa-miR-515-5p, hsa-miR-520h, hsa-miR-519d, and hsa-miR-526b) from the chromosome 19 microRNA cluster were identified as FGR placenta-specific microRNAs. Four FGR placenta-specific microRNAs (hsa-miR-518b, hsa-miR-1323, hsa-miR-520h, and hsa-miR-519d) were confirmed as FGR pregnancy-associated, placenta-specific miRNAs, but their circulating levels in maternal plasma showed no significant differences between FGR pregnancy and uncomplicated pregnancy. CONCLUSION: Our data suggest that reduced expression in placenta of certain FGR placenta-specific miRNAs is associated with FGR and that the discrepancy between expression in FGR placenta and their circulating levels in maternal plasma will be crucial to understanding how placenta-specific microRNAs are released into the maternal circulation.

Small serum protein-1 changes the susceptibility of an apoptosis-inducing metalloproteinase HV1 to a metalloproteinase inhibitor in habu snake (Trimeresurus flavoviridis).

Viperidae snakes containing various venomous proteins also have several anti-toxic proteins in their sera. However, the physiological function of serum protein has been elucidated incompletely. Small serum protein (SSP)-1 is a major component of the SSPs isolated from the serum of a Japanese viper, the habu snake (Trimeresurus flavoviridis). It exists in the blood as a binary complex with habu serum factor (HSF), a snake venom metalloproteinase inhibitor. Affinity chromatography of the venom on an SSP-1-immobilized column identified HV1, an apoptosis-inducing metalloproteinase, as the target protein of SSP-1. Biacore measurements revealed that SSP-1 was bound to HV1 with a dissociation constant of 8.2 × 10⁻8 M. However, SSP-1 did not inhibit the peptidase activity of HV1. Although HSF alone showed no inhibitory activity or binding affinity to HV1, the SSP-1-HSF binary complex bound to HV1 formed a ternary complex that non-competitively inhibited the peptidase activity of HV1 with a inhibition constant of 5.1 ± 1.3 × 10⁻9 M. The SSP-1-HSF complex also effectively suppressed the apoptosis of vascular endothelial cells and caspase 3 activation induced by HV1. Thus, SSP-1 is a unique protein that non-covalently attaches to HV1 and changes its susceptibility to HSF.

Prenylated acylphloroglucinols, chipericumins A-D, from Hypericum chinense.

Two new tetracyclic prenylated acylphloroglucinols, chipericumins A (1) and B (2), were isolated from the roots of Hypericum chinense, together with two new tricyclic prenylated acylphloroglucinols, chipericumins C (3) and D (4). Their structures were elucidated by spectroscopic data. Chipericumins A-D (1-4) are prenylated acylphloroglucinols having a spiro skeleton with an acyl group, a methyl group, a C(5) unit, and a monoterpene moiety in common.

Biyoulactones A-C, new pentacyclic meroterpenoids from Hypericum chinense.

Three novel pentacyclic meroterpenoids with a unique dilactone structure containing C-C bonded bi- and tricyclic γ-lactone moieties, biyoulactones A-C (1-3), were isolated from the roots of Hypericum chinense, and their structures were elucidated on the basis of spectroscopic data. The relative and absolute stereochemistry of 1 was assigned by a combination of NOESY and a single crystal X-ray diffraction analysis.

Epidemiology of human papillomavirus genotypes in pregnant Japanese women.

To investigate the pre-vaccination epidemiology of genital human papillomavirus (HPV) infections and genotypes in pregnant Japanese women, we performed Pap smear tests and HPV genotype testing in patients attending Nagasaki University Hospital and collaborating hospitals from August 2007 to July 2010. Serial uterine cervical specimens were obtained from 151 pregnant women. The HPV test was positive on the first visit in 54 women (35.8%; 54/151, average age 30). A total of 49 women (32.5%; 49/151) were infected by at least one high-risk HPV and 5 women were infected by only low-risk HPV. The three most prevalent high-risk HPV genotypes were HPV 52 (31.5%; 17/54), HPV 16 (29.6%; 16/51) and HPV 31 (13.0%; 7/51). The HPV infection pattern (negative, single infection and multiple infection) differed significantly according to the pregnancy trimester (χ(2)-test; P<0.01(Pearson)). Among HPV-infected pregnant Japanese women, HPV52 was the most common genotype. The second most common genotype was HPV16, and these two genotypes accounted for ∼60% of HPV-positive pregnant women. Infection with multiple HPV genotypes was observed more frequently in the first trimester of pregnancy and the pattern of infection changed significantly depending on pregnancy stage.

Clinical application of fetal sex determination using cell-free fetal DNA in pregnant carriers of X-linked genetic disorders.

As the first step in prenatal diagnosis of X-linked genetic disorders, chorionic villus sampling (CVS) for fetal sex determination is generally performed at 11-13 weeks of gestation. However, as the procedure-related miscarriage rate of CVS is 0.5-1.0%, non-invasive methods such as PCR of cell-free fetal DNA (cff-DNA) in maternal plasma are preferable. Here, we determined fetal sex at 9-12 weeks of gestation using PCR of cff-DNA in three pregnant carriers of Duchenne muscular dystrophy. The fetal sex was accurately determined in all three cases, as confirmed by ultrasound and amniocentesis at 16 weeks (for the two female fetuses) and CVS at 12 weeks (for the one male fetus). This procedure could avoid unnecessary CVS in female fetuses.