The role of pregnancy associated plasma protein-A in triple negative breast cancer: a promising target for achieving clinical benefits.

Pregnancy associated plasma protein-A (PAPP-A) plays an integral role in breast cancer (BC), especially triple negative breast cancer (TNBC). This subtype accounts for the most aggressive BC, possesses high tumor heterogeneity, is least responsive to standard treatments and has the poorest clinical outcomes. There is a critical need to address the lack of effective targeted therapeutic options available. PAPP-A is a protein that is highly elevated during pregnancy. Frequently, higher PAPP-A expression is detected in tumors than in healthy tissues. The increase in expression coincides with increased rates of aggressive cancers. In BC, PAPP-A has been demonstrated to play a role in tumor initiation, progression, metastasis including epithelial-mesenchymal transition (EMT), as well as acting as a biomarker for predicting patient outcomes. In this review, we present the role of PAPP-A, with specific focus on TNBC. The structure and function of PAPP-A, belonging to the pappalysin subfamily, and its proteolytic activity are assessed. We highlight the link of BC and PAPP-A with respect to the IGFBP/IGF axis, EMT, the window of susceptibility and the impact of pregnancy. Importantly, the relevance of PAPP-A as a TNBC clinical marker is reviewed and its influence on immune-related pathways are explored. The relationship and mechanisms involving PAPP-A reveal the potential for more treatment options that can lead to successful immunotherapeutic targets and the ability to assist with better predicting clinical outcomes in TNBC.

Aspirin for evidence-based preeclampsia prevention trial: effects of aspirin on maternal serum pregnancy-associated plasma protein A and placental growth factor trajectories in pregnancy.

BACKGROUND: The exact mechanism by which aspirin prevents preeclampsia remains unclear. Its effects on serum placental biomarkers throughout pregnancy are also unknown. OBJECTIVE: To investigate the effects of aspirin on serum pregnancy-associated plasma protein A and placental growth factor trajectories using repeated measures from women at increased risk of preterm preeclampsia. STUDY DESIGN: This was a longitudinal secondary analysis of the Combined Multimarker Screening and Randomized Patient Treatment with Aspirin for Evidence-based Preeclampsia Prevention trial using repeated measures of pregnancy-associated plasma protein A and placental growth factor. In the trial, 1620 women at increased risk of preterm preeclampsia were identified using the Fetal Medicine Foundation algorithm at 11 to 13+6 weeks of gestation, of whom 798 were randomly assigned to receive aspirin 150 mg and 822 to receive placebo daily from before 14 weeks to 36 weeks of gestation. Serum biomarkers were measured at baseline and follow-up visits at 19 to 24, 32 to 34, and 36 weeks of gestation. Generalized additive mixed models with treatment by gestational age interaction terms were used to investigate the effect of aspirin on biomarker trajectories over time. RESULTS: Overall, there were 5507 pregnancy-associated plasma protein A and 5523 placental growth factor measurements. Raw pregnancy-associated plasma protein A values increased over time, and raw placental growth factor increased until 32 weeks of gestation followed by a decline. The multiple of the median mean values of the same biomarkers were consistently below 1.0 multiple of the median, reflecting the high-risk profile of the study population. Trajectories of mean pregnancy-associated plasma protein A and placental growth factor multiple of the median values did not differ significantly between the aspirin and placebo groups (aspirin treatment by gestational age interaction P values: .259 and .335, respectively). CONCLUSION: In women at increased risk of preterm preeclampsia, aspirin 150 mg daily had no significant effects on pregnancy-associated plasma protein A or placental growth factor trajectories when compared to placebo.

First trimester screening for pre-eclampsia and targeted aspirin prophylaxis: a cost-effectiveness cohort study.

OBJECTIVE: Investigate cost-effectiveness of first trimester pre-eclampsia screening using the Fetal Medicine Foundation (FMF) algorithm and targeted aspirin prophylaxis in comparison with standard care. DESIGN: Retrospective observational study. SETTING: London tertiary hospital. POPULATION: 5957 pregnancies screened for pre-eclampsia using the National Institute for Health and Care Excellence (NICE) method. METHODS: Differences in pregnancy outcomes between those who developed pre-eclampsia, term pre-eclampsia and preterm pre-eclampsia were compared by the Kruskal-Wallis and Chi-square tests. The FMF algorithm was applied retrospectively to the cohort. A decision analytic model was used to estimate costs and outcomes for pregnancies screened using NICE and those screened using the FMF algorithm. The decision point probabilities were calculated using the included cohort. MAIN OUTCOME MEASURES: Incremental healthcare costs and QALY gained per pregnancy screened. RESULTS: Of 5957 pregnancies, 12.8% and 15.9% were screen-positive for development of pre-eclampsia using the NICE and FMF methods, respectively. Of those who were screen-positive by NICE recommendations, aspirin was not prescribed in 25%. Across the three groups, namely, pregnancies without pre-eclampsia, term pre-eclampsia and preterm pre-eclampsia there was a statistically significant trend in rates of emergency caesarean (respectively 21%, 43% and 71.4%; P < 0.001), admission to neonatal intensive care unit (NICU) (5.9%, 9.4%, 41%; P < 0.001) and length of stay in NICU. The FMF algorithm was associated with seven fewer cases of preterm pre-eclampsia, cost saving of £9.06 and QALY gain of 0.00006/pregnancy screened. CONCLUSIONS: Using a conservative approach, application of the FMF algorithm achieved clinical benefit and an economic cost saving.

Validation of machine-learning model for first-trimester prediction of pre-eclampsia using cohort from PREVAL study.

OBJECTIVE: Effective first-trimester screening for pre-eclampsia (PE) can be achieved using a competing-risks model that combines risk factors from the maternal history with multiples of the median (MoM) values of biomarkers. A new model using artificial intelligence through machine-learning methods has been shown to achieve similar screening performance without the need for conversion of raw data of biomarkers into MoM. This study aimed to investigate whether this model can be used across populations without specific adaptations. METHODS: Previously, a machine-learning model derived with the use of a fully connected neural network for first-trimester prediction of early (< 34 weeks), preterm (< 37 weeks) and all PE was developed and tested in a cohort of pregnant women in the UK. The model was based on maternal risk factors and mean arterial blood pressure (MAP), uterine artery pulsatility index (UtA-PI), placental growth factor (PlGF) and pregnancy-associated plasma protein-A (PAPP-A). In this study, the model was applied to a dataset of 10 110 singleton pregnancies examined in Spain who participated in the first-trimester PE validation (PREVAL) study, in which first-trimester screening for PE was carried out using the Fetal Medicine Foundation (FMF) competing-risks model. The performance of screening was assessed by examining the area under the receiver-operating-characteristics curve (AUC) and detection rate (DR) at a 10% screen-positive rate (SPR). These indices were compared with those derived from the application of the FMF competing-risks model. The performance of screening was poor if no adjustment was made for the analyzer used to measure PlGF, which was different in the UK and Spain. Therefore, adjustment for the analyzer used was performed using simple linear regression. RESULTS: The DRs at 10% SPR for early, preterm and all PE with the machine-learning model were 84.4% (95% CI, 67.2-94.7%), 77.8% (95% CI, 66.4-86.7%) and 55.7% (95% CI, 49.0-62.2%), respectively, with the corresponding AUCs of 0.920 (95% CI, 0.864-0.975), 0.913 (95% CI, 0.882-0.944) and 0.846 (95% CI, 0.820-0.872). This performance was achieved with the use of three of the biomarkers (MAP, UtA-PI and PlGF); inclusion of PAPP-A did not provide significant improvement in DR. The machine-learning model had similar performance to that achieved by the FMF competing-risks model (DR at 10% SPR, 82.7% (95% CI, 69.6-95.8%) for early PE, 72.7% (95% CI, 62.9-82.6%) for preterm PE and 55.1% (95% CI, 48.8-61.4%) for all PE) without requiring specific adaptations to the population. CONCLUSIONS: A machine-learning model for first-trimester prediction of PE based on a neural network provides effective screening for PE that can be applied in different populations. However, before doing so, it is essential to make adjustments for the analyzer used for biochemical testing. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.

Maternal serum biomarkers of placental insufficiency at 24-28 weeks of pregnancy in relation to the risk of delivering small-for-gestational-age infant in Sylhet, Bangladesh: a prospective cohort study.

BACKGROUND: Small-for-gestational-age (SGA), commonly caused by poor placentation, is a major contributor to global perinatal mortality and morbidity. Maternal serum levels of placental protein and angiogenic factors are changed in SGA. Using data from a population-based pregnancy cohort, we estimated the relationships between levels of second-trimester pregnancy-associated plasma protein-A (PAPP-A), placental growth factor (PlGF), and serum soluble fms-like tyrosine kinase-1 (sFlt-1) with SGA. METHODS: Three thousand pregnant women were enrolled. Trained health workers prospectively collected data at home visits. Maternal blood samples were collected, serum aliquots were prepared and stored at -80℃. Included in the analysis were 1,718 women who delivered a singleton live birth baby and provided a blood sample at 24-28 weeks of gestation. We used Mann-Whitney U test to examine differences of the median biomarker concentrations between SGA (< 10th centile birthweight for gestational age) and appropriate-for-gestational-age (AGA). We created biomarker concentration quartiles and estimated the risk ratios (RRs) and 95% confidence intervals (CIs) for SGA by quartiles separately for each biomarker. A modified Poisson regression was used to determine the association of the placental biomarkers with SGA, adjusting for potential confounders. RESULTS: The median PlGF level was lower in SGA pregnancies (934 pg/mL, IQR 613-1411 pg/mL) than in the AGA (1050 pg/mL, IQR 679-1642 pg/mL; p < 0.001). The median sFlt-1/PlGF ratio was higher in SGA pregnancies (2.00, IQR 1.18-3.24) compared to AGA pregnancies (1.77, IQR 1.06-2.90; p = 0.006). In multivariate regression analysis, women in the lowest quartile of PAPP-A showed 25% higher risk of SGA (95% CI 1.09-1.44; p = 0.002). For PlGF, SGA risk was higher in women in the lowest (aRR 1.40, 95% CI 1.21-1.62; p < 0.001) and 2nd quartiles (aRR 1.30, 95% CI 1.12-1.51; p = 0.001). Women in the highest and 3rd quartiles of sFlt-1 were at reduced risk of SGA delivery (aRR 0.80, 95% CI 0.70-0.92; p = 0.002, and aRR 0.86, 95% CI 0.75-0.98; p = 0.028, respectively). Women in the highest quartile of sFlt-1/PlGF ratio showed 18% higher risk of SGA delivery (95% CI 1.02-1.36; p = 0.025). CONCLUSIONS: This study provides evidence that PAPP-A, PlGF, and sFlt-1/PlGF ratio measurements may be useful second-trimester biomarkers for SGA.

First trimester maternal serum PAPP-A and free ß-hCG levels and risk of SGA or LGA in women with and without GDM.

BACKGROUND: Maternal gestational diabetes (GDM), small (SGA) and large (LGA) for gestational age neonates are associated with increased morbidity in both mother and child. We studied how different levels of first trimester pregnancy associated plasma protein-A (PAPP-A) and free beta human chorionic gonadotropin (fß-hCG) were associated with SGA and LGA in GDM pregnancies and controls. METHODS: Altogether 23 482 women with singleton pregnancies participated in first trimester combined screening and delivered between 2014 and 2018 in Northern Finland and were included in this retrospective case-control study. Women with GDM (n = 4697) and controls without GDM (n = 18 492) were divided into groups below 5th and 10th or above 90th and 95th percentile (pc) PAPP-A and fß-hCG MoM levels. SGA was defined as a birthweight more than two standard deviations (SD) below and LGA more than two SDs above the sex-specific and gestational age-specific reference mean. Odds ratios were adjusted (aOR) for maternal age, BMI, ethnicity, IVF/ICSI, parity and smoking. RESULTS: In pregnancies with GDM the proportion of SGA was 2.6% and LGA 4.5%, compared to 3.3% (p = 0.011) and 1.8% (p < 0.001) in the control group, respectively. In ≤ 5th and ≤ 10th pc PAPP-A groups, aORs for SGA were 2.7 (95% CI 1.5-4.7) and 2.2 (95% CI 1.4-3.5) in the GDM group and 3.8 (95% CI 3.0-4.9) and 2.8 (95% CI 2.3-3.5) in the reference group, respectively. When considering LGA, there was no difference in aORs in any high PAPP-A groups. In the low ≤ 5 percentile fß-hCG MoM group, aORs for SGA was 2.3 (95% CI 1.8-3.1) in the control group. In fß-hCG groups with GDM there was no association with SGA and the only significant difference was ≥ 90 percentile group, aOR 1.6 (95% CI 1.1-2.5) for LGA. CONCLUSION: Association with low PAPP-A and SGA seems to be present despite GDM status. High PAPP-A levels are not associated with increased LGA risk in women with or without GDM. Low fß-hCG levels are associated with SGA only in non-GDM pregnancies.

Association between aneuploidy screening analytes and adverse outcomes in twin gestations.

OBJECTIVES: To evaluate associations between serum analytes used for genetic screening and obstetric complications among twin pregnancies. METHODS: This cohort included twins delivered at a tertiary care hospital from 2009 to 2017. Abnormal levels of pregnancy associated plasma protein (PAPP-A), first and second trimester human chorionic gonadotropin (hCG), alpha fetoprotein (AFP), estriol, and inhibin, reported as multiples of the median (MoM), were defined as <5 %ile or >95 %ile for our cohort. Associations between abnormal analytes and preterm delivery, small for gestational age, and pregnancy-associated hypertension were calculated using Fisher's exact test. RESULTS: A total of 357 dichorionic/diamniotic and 123 monochorionic/diamniotic twins were included. Among dichorionic/diamniotic twins, elevated AFP (>3.70 MoM) was associated with increased preterm delivery <34 weeks (44.4 vs. 16.5 %, p=0.007), while elevated inhibin (>4.95 MoM) was associated with increased preterm delivery<37 weeks (94.1 vs. 58.8 %, p=0.004). For monochorionic/diamniotic twins, elevated inhibin (>6.34 MoM) was associated increased preterm delivery <34 weeks (66.7 vs. 24.8 %, p=0.04) and hypertension (66.7 vs. 21.4 %, p=0.03). CONCLUSIONS: Selected abnormal analyte levels were associated with increased rates of adverse outcomes in twin pregnancies, which differed by chorionicity. Our findings assist providers in interpreting abnormal analyte levels in twin pregnancies and may help to identify those at increased risk for adverse outcomes.

Association of low pregnancy associated plasma protein-A with increased umbilical artery pulsatility index in cases of fetal weight between the 3rd and 10th percentiles: a retrospective cohort study.

OBJECTIVES: This study aims to evaluate if low levels of serum maternal pregnancy associated plasma protein-A (PAPP-A) during the first trimester are related to increased umbilical artery pulsatility index (UA PI) later in pregnancy, in cases of estimated fetal weight between the 3rd and 10th percentiles, in order to establish PAPP-A as a predictor of this particular cases of fetal growth restriction (FGR). METHODS: An observational, retrospective cohort study, conducted at a tertiary University Hospital located in Oporto, Portugal. Pregnant women who did the first trimester combined screening, between May 2013 and June 2020 and gave birth in the same hospital, with an estimated fetal weight (EFW) between the 3rd and 10th percentiles were included. The primary outcome is the difference in increased UA PI prevalence between two groups: PAPP-A<0.45 MoM and PAPP-A≥0.45 MoM. As secondary outcomes were evaluated differences in neonatal weight, gestational age at delivery, cesarean delivery, neonatal intensive care unit hospitalization, 5-min Apgar score below 7 and live birth rate between the same two groups. RESULTS: We included 664 pregnancies: 110 cases of PAPP-A<0.45 MoM and 554 cases with PAPP-A≥0.45 MoM. Increased UA PI prevalence, which was the primary outcome of this study, was significantly different between the two groups (p=0.005), as the PAPP-A<0.45 MoM group presents a higher prevalence (12.7 %) when compared to the PAPP-A≥0.45 MoM group (5.4 %). The secondary outcome cesarean delivery rate was significantly different between the groups (p=0.014), as the PAPP-A<0.45 MoM group presents a higher prevalence (42.7 %) than the PAPP-A≥0.45 MoM group (30.1 %). No other secondary outcomes showed differences between the two groups. CONCLUSIONS: There is an association of low serum maternal PAPP-A (<0.45 MoM) during the first trimester and increased UA PI (>95th percentile) later in pregnancy, in cases of EFW between the 3rd and 10th percentiles. However, this association is not strong enough alone for low PAPP-A to be a reliable predictor of increased UA PI in this population.

Investigation of cardiovascular risk parameters in adolescents with metabolic syndrome.

BACKGROUND: Metabolic syndrome leading to type 2 diabetes mellitus and cardiovascular diseases is a chronic multifactorial syndrome, associated with low-grade inflammation status. In our study, we aimed at assessing the serum levels of follistatin (FST), pregnancy-associated plasma protein-A (PAPP-A), and platelet/endothelial cell adhesion molecule-1 (PECAM-1) in adolescent patients with metabolic syndrome. METHODS: This study was performed in 43 (19 males, 24 females) metabolic syndrome adolescents and 37 lean controls matched for age and sex. The serum levels of FST, PECAM-1, and PAPP-A were measured by using ELISA method. RESULTS: Serum FST and PAPP-A levels in metabolic syndrome were significantly higher than those of controls (p < 0.005 and p < 0.05). However, there was no difference in serum PECAM-1 levels between metabolic syndrome and control groups (p = 0.927). There was a significant positive correlation between serum FST and triglyceride (r = 0.252; p < 0.05), and PAPP-A and weight, (r = 0.252; p < 0.05) in metabolic syndrome groups. Follistatin was determined statistically significant in both univariate (p = 0,008) and multivariate (p = 0,011) logistic regression analysis. CONCLUSIONS: Our findings indicated a significant relationship between FST and PAPP-A levels and metabolic syndrome. These findings offer the possibility of using these markers in diagnosis of metabolic syndrome in adolescents as the prevention of the future complications.

The role of second trimester uterine artery Doppler in predicting obstetric and neonatal outcomes in abnormal first trimester maternal serum pregnancy-associated plasma protein-A and free ß-human chorionic gonadotropin values.

AIM: This study aims to determine whether second-trimester uterine artery (UtA) Doppler combined with first-trimester abnormal pregnancy-associated plasma protein-A (PAPP-A) and ß-human chorionic gonadotropin (ß-Hcg) levels predicts adverse obstetric and neonatal outcomes. MATERIALS AND METHODS: This study of 289 pregnant women included 196 with normal PAPP-A and free ß-HCG values (control group) and 93 with abnormal values (study group) in the first-trimester screening test. Second-trimester UtA Doppler sonography was done in these pregnancies. The perinatal prediction and screening potential of UtA Doppler pulsatility index (PI) parameters were examined in the study group. RESULTS: UtA PI >95 percentile increased birth before the 37th week by 4.46 times, birth before the 34th week by 7.44 times, preeclampsia risk by 3.25 times, fetal growth restriction (FGR) risk by 4.89 times, and neonatal intensive care unit (NICU) admission rates by 3.66 times in the study group (p < 0.05 for all). UtA PI >95 percentile had 49.2% sensitivity and 82.1% specificity for birth before 37 weeks. For birth before 34 weeks, sensitivity was 80.0% and specificity 65.0%. FGR has 70.5% sensitivity and 67.1% specificity. Screening for preeclampsia has 66.6% sensitivity and 61.9% specificity. CONCLUSION: Adding UtA Doppler in the second trimester to pregnancies with abnormal PAPP-A and/or free ß-Hcg values in the first trimester may be a useful screening method for adverse outcomes.

The IGF-PAPP-A-Stanniocalcin Axis in Serum and Ascites Associates with Prognosis in Patients with Ovarian Cancer.

Pregnancy-associated plasma protein-A (PAPP-A) and PAPP-A2 modulate insulin-like growth factor (IGF) action and are inhibited by the stanniocalcins (STC1 and STC2). We previously demonstrated increased PAPP-A and IGF activity in ascites from women with ovarian carcinomas. In this prospective, longitudinal study of 107 women with ovarian cancer and ascites accumulation, we determined corresponding serum and ascites levels of IGF-1, IGF-2, PAPP-A, PAPP-A2, STC1, and STC2 and assessed their relationship with mortality. As compared to serum, we found highly increased ascites levels of PAPP-A (51-fold) and PAPP-A2 (4-fold). Elevated levels were also observed for IGF-1 (12%), STC1 (90%) and STC2 (68%). In contrast, IGF-2 was reduced by 29% in ascites. Patients were followed for a median of 38.4 months (range: 45 days to 8.9 years), during which 73 patients (68.2%) died. Overall survival was longer for patients with high serum IGF-1 (hazard ratio (HR) per doubling in protein concentration: 0.60, 95% CI: 0.40-0.90). However, patients with high ascites levels of IGF-1 showed a poorer prognosis (HR: 2.00 (1.26-3.27)). High serum and ascites IGF-2 levels were associated with increased risk of mortality (HR: 2.01 (1.22-3.30) and HR: 1.78 (1.24-2.54), respectively). Similarly, serum PAPP-A2 was associated with mortality (HR: 1.26 (1.08-1.48)). Our findings demonstrate the presence and activity of the IGF system in the local tumor ecosystem, which is likely a characteristic feature of malignant disease and plays a role in its peritoneal dissemination. The potential clinical implications are supported by our finding that serum levels of the proteins are associated with patient prognosis.

Reconsidering the use of race adjustments in maternal serum screening.

The use of race in maternal serum screening is problematic because race is a social construct rather than a distinct biological classifier. Nevertheless, laboratories offering this testing are encouraged to use race-specific cutoff values for maternal serum screening biomarkers to determine the risk of fetal abnormalities. Large cohort studies examining racial differences in maternal serum screening biomarker concentrations have yielded conflicting results, which we postulate may be explained by genetic and socioeconomic differences between racial cohorts in different studies. We recommend that the use of race in maternal serum screening should be abandoned. Further research is needed to identify socioeconomic and environmental factors that contribute to differences in maternal serum screening biomarker concentrations observed between races. A better understanding of these factors may facilitate accurate race-agnostic risk estimates for aneuploidy and neural tube defects.

Correlation between PAPP-A serum levels in the first trimester of pregnancy with the occurrence of gestational diabetes, a multicenter cohort study.

OBJECTIVE: This study aimed to investigate the association between first-trimester Pregnancy-associated plasma protein A (PAPP-A) levels and subsequent gestational diabetes mellitus (GDM) development. METHOD: The study was conducted on 5854 pregnant women who attended routine prenatal care. Maternal biomarkers, including PAPP-A and free beta hCG, were measured for all women in a referral laboratory and converted to MoM values. Pregnant women were divided into two groups, based on the serum concentration of PAPP-A, (PAPP-A > 0.4 (normal) and PAPP-A < 0.4 (low)). Data on the screening test for GDM and pregnancy outcomes were collected and analyzed with appropriate tests. RESULT: Of the 5854 pregnant women, 889 (15.19%) developed GDM. The maternal PAPP-A MoM concentrations were significantly lower in GDM cases compared to controls. Indeed, gestational age at delivery and birth weight were significantly lower (p < 0.001) in PAPP-A MoM < 0.4, and the rate of intrauterine growth restriction (IUGR) was significantly higher (p < 0.001). ROC analysis revealed that the sensitivity and specificity of MoM concentration for predicting GDM were 53.3% and 51.9%, respectively. CONCLUSION: Lower maternal PAPP-A in early pregnancy can lead to glucose intolerance and increase the risk of subsequent GDM development. In addition, decreased serum concentration of PAPP-A is significantly correlated to lower birth weight and IUGR.

High levels of hemolysis do not affect measurement of PAPP-A, ß-HCG and TRAb on BRAHMS KRYPTOR compact plus.

To assess the impact of high levels of hemolysis on the laboratory results for free ß-hCG, PAPP-A, and TRAb performed on the B·R·A·H·M·S KRYPTOR Compact PLUS. Adapted from the CLSI guidelines EP07-A2, paired difference testing was performed on serum samples from the routine laboratory workflow. Three sample pools for each assessed analyte was prepared and subjected to increased levels of added hemolysate. For ß-hCG and PAPP-A, the relative difference in the measured analyte concentration between the sample with 0 g/L added Hb and the samples with increasing free Hb concentrations (up to 6 g/L), was well below the pre-set acceptance criterion of 10% at all levels. The TRAb results showed greater variation than the other analytes, likely a consequence of imprecision rather than hemolysis. Hemolysis has a negligible effect on the analysis results of free beta-hCG, PAPP-A and TRAb measured on the B·R·A·H·M·S KRYPTOR Compact PLUS.

First trimester low maternal serum pregnancy associated plasma protein-A (PAPP-A) as a screening method for adverse pregnancy outcomes.

OBJECTIVES: To evaluate different cut-off values of first trimester pregnancy associated plasma protein-A (PAPP-A) in screening for adverse pregnancy outcomes in a retrospective cohort study. METHODS: During the study period of 1.1.2014-31.12.2018, total of 23,482 women with singleton pregnancies participated in first trimester combined screening for chromosomal abnormalities. Maternal serum PAPP-A multiple of medians (MoM) levels were measured, and study population was divided into three study groups of PAPP-A ≤0.40 (n=1,030), ≤0.35 (n=630) and ≤0.30 (n=363) MoM. RESULTS: Small for gestational age (SGA), preterm birth (PTB) and composite outcome (SGA, hypertensive disorder of pregnancy (HDP) and/or PTB) were more frequent in all three PAPP-A MoM study groups and pre-eclampsia in ≤0.40 and ≤0.35 study groups than in their control groups (p < 0.05). The odds ratio (OR) for SGA varied from 3.7 to 5.4 and sensitivity and specificity from 6.9 to 13.8% and from 95.9 to 98.6%, between study groups. Using PAPP-A ≤0.30 MoM as a screening cut-off instead of PAPP-A ≤0.40 MoM, resulted in approximately 50% reduction in screening detection of SGA and PTB. CONCLUSIONS: PAPP-A ≤0.40 MoM should be considered as a primary screening cut-off for adverse pregnancy outcomes as approximately 23% will develop either SGA, HDP or PTB. It seems to be the best cut-off to screen for SGA.

Placental Growth Factor and Pregnancy-Associated Plasma Protein-A as Potential Early Predictors of Gestational Diabetes Mellitus.

Gestational diabetes mellitus (GDM) is one of the most common pregnancy complications and one of the main causes of adverse pregnancy outcomes. An early diagnosis of GDM is of fundamental importance in clinical practice. However, the major professional organizations recommend universal screening for GDM, using a 75 g oral glucose tolerance test at 24-28 weeks of gestation. A selective screening at an early stage of pregnancy is recommended only if there are maternal risk factors for diabetes. As a result, the GDM diagnosis is often delayed and established after the appearance of complications. The manifestation of GDM is directly related to insulin resistance, which is closely associated with endothelial dysfunction. The placenta, the placental peptides and hormones play a pivotal role in the manifestation and progression of insulin resistance during pregnancy. Recently, the placental growth factor (PlGF) and plasma-associated protein-A (PAPP-A), have been shown to significantly affect both insulin sensitivity and endothelial function. The principal function of PAPP-A appears to be the cleavage of circulating insulin-like growth factor binding protein-4 while PlGF has been shown to play a central role in the development and maturation of the placental vascular system and circulation. On one hand, these factors are widely used as early predictors (11-13 weeks of gestation) of complications during pregnancy, such as preeclampsia and fetal aneuploidies, in most countries. On the other hand, there is increasing evidence for their predictive role in the development of carbohydrate disorders, but some studies are rather controversial. Therefore, this review aims to summarize the available literature about the potential of serum levels of PlGF and PAPP-A as early predictors in the diagnosis of GDM.

Placental protein levels in maternal serum are associated with adverse pregnancy outcomes in nulliparous patients.

BACKGROUND: The Eunice Kennedy Shriver National Institute of Child Health and Human Development Nulliparous Pregnancy Outcomes Study: Monitoring Mothers-to-Be was established to investigate the underlying causes and pathophysiological pathways associated with adverse pregnancy outcomes in nulliparous gravidas. OBJECTIVE: This study aimed to study placental physiology and identify novel biomarkers concerning adverse pregnancy outcomes, including preterm birth (medically indicated and spontaneous), preeclampsia, small-for-gestational-age neonates, and stillbirth. We measured levels of placental proteins in the maternal circulation in the first 2 trimesters of pregnancy. STUDY DESIGN: Maternal serum samples were collected at 2 study visits (6-13 weeks and 16-21 weeks), and levels of 9 analytes were measured. The analytes we measured were vascular endothelial growth factor, placental growth factor, endoglin, soluble fms-like tyrosine kinase-1, A disintegrin and metalloproteinase domain-containing protein 12, pregnancy-associated plasma protein A, free beta-human chorionic gonadotropin, inhibin A, and alpha-fetoprotein. The primary outcome was preterm birth between 20 0/7 and 36 6/7 weeks of gestation. The secondary outcomes were spontaneous preterm births, medically indicated preterm births, preeclampsia, small-for-gestational-age neonates, and stillbirth. RESULTS: A total of 10,038 eligible gravidas were enrolled in the Nulliparous Pregnancy Outcomes Study: Monitoring Mothers-to-Be cohort, from which a nested case-control study was performed comparing 800 cases with preterm birth (466 spontaneous preterm births, 330 medically indicated preterm births, and 4 unclassified preterm births), 568 with preeclampsia, 406 with small-for-gestational-age birth, and 49 with stillbirth with 911 controls who delivered at term without complications. Although levels of each analyte generally differed between cases and controls at 1 or 2 visits, the odds ratios revealed a <2-fold difference between cases and controls in all comparisons. Receiver operating characteristic curves, generated to determine the relationship between analyte levels and preterm birth and the other adverse pregnancy outcomes, resulted in areas under the receiver operating characteristic curves that were relatively low (range, 0.50-0.64) for each analyte. Logistic regression modeling demonstrated that areas under the receiver operating characteristic curves for predicting adverse pregnancy outcomes were greater using baseline clinical characteristics and combinations of analytes than baseline characteristics alone, but areas under the receiver operating characteristic curves remained relatively low for each outcome (range, 0.65-0.78). CONCLUSION: We have found significant associations between maternal serum levels of analytes evaluated early in pregnancy and subsequent adverse pregnancy outcomes in nulliparous gravidas. However, the test characteristics for these analytes do not support their use as clinical biomarkers to predict adverse pregnancy outcomes, either alone or in combination with maternal clinical characteristics.

Serum PlGF compared with PAPP-A in first trimester screening for preterm pre-eclampsia: Adjusting for the effect of aspirin treatment.

OBJECTIVE: To compare the predictive performance for preterm-pre-eclampsia (PE) in first-trimester screening by serum placental growth factor (PlGF) versus pregnancy associated plasma protein-A (PAPP-A), in combination with maternal risk factors, mean arterial pressure (MAP) and uterine artery pulsatility index (UtA-PI), after adjustment for the effect of aspirin in women receiving this treatment. DESIGN: Non-intervention multicentre screening studies for PE in singleton pregnancies. SETTING: Maternity hospitals. POPULATION: Two independent prospective studies of 8775 and 16 451 women with singleton pregnancies attending for routine assessment at 11+0 -13+6 weeks' gestation. METHODS: The competing risks model was used to estimate patient-specific risks of delivery with PE at <37 weeks' gestation based on maternal risk factors and combinations with MAP, UtA-PI and either PlGF or PAPP-A. McNemar's test was used to compare the detection rate (DR) of preterm-PE of screening utilising PlGF versus PAPP-A, after adjustments for the effects of aspirin. MAIN OUTCOME MEASURE: Predictive performance for preterm-PE. RESULTS: In the combined data of 25 226 women, including 678 (2.7%) who developed PE, there were 194(0.8%) with preterm-PE. Addition of PlGF improved the DR of preterm-PE, at 10% screen positive rate, by 18.4% (95% CI 12.2-24.6) in screening by maternal risk factors, by 19.9% (95% CI 13.6-26.2) in screening by maternal factors and MAP, and by 7.0% (95% CI 2.3-11.6) in screening by maternal factors, MAP and UtA-PI. PAPP-A did not significantly improve the DR provided by any combination of biomarkers. CONCLUSION: The predictive performance of first trimester PlGF for preterm-PE is superior to that of PAPP-A.

Modified multiple marker aneuploidy screening as a primary screening test for preeclampsia.

BACKGROUND: Abnormal levels of maternal biochemical markers used in multiple marker aneuploidy screening have been associated with adverse pregnancy outcomes. This study aims to assess if a combination of maternal characteristics and biochemical markers in the first and second trimesters can be used to screen for preeclampsia (PE). The secondary aim was to assess this combination in identifying pregnancies at risk for gestational hypertension and preterm birth. METHODS: This case-control study used information on maternal characteristics and residual blood samples from pregnant women who have undergone multiple marker aneuploidy screening. The median multiple of the median (MoM) of first and second trimester biochemical markers in cases (women with PE, gestational hypertension and preterm birth) and controls were compared. Biochemical markers included pregnancy-associated plasma protein A (PAPP-A), placental growth factor (PlGF), human chorionic gonadotropin (hCG), alpha feto-protein (AFP), unconjugated estriol (uE3) and Inhibin A. Logistic regression analysis was used to estimate screening performance using different marker combinations. Screening performance was defined as detection rate (DR) and false positive rate (FPR). Preterm and early-onset preeclampsia PE were defined as women with PE who delivered at < 37 and < 34 weeks of gestation, respectively. RESULTS: There were 147 pregnancies with PE (81 term, 49 preterm and 17 early-onset), 295 with gestational hypertension, and 166 preterm birth. Compared to controls, PE cases had significantly lower median MoM of PAPP-A (0.77 vs 1.10, p < 0.0001), PlGF (0.76 vs 1.01, p < 0.0001) and free-ß hCG (0.81 vs. 0.98, p < 0.001) in the first trimester along with PAPP-A (0.82 vs 0.99, p < 0.01) and PlGF (0.75 vs 1.02, p < 0.0001) in the second trimester. The lowest first trimester PAPP-A, PlGF and free ß-hCG were seen in those with preterm and early-onset PE. At a 20% FPR, 67% of preterm and 76% of early-onset PE cases can be predicted using a combination of maternal characteristics with PAPP-A and PlGF in the first trimester. The corresponding DR was 58% for gestational hypertension and 36% for preterm birth cases. CONCLUSIONS: Maternal characteristics with first trimester PAPP-A and PlGF measured for aneuploidy screening provided reasonable accuracy in identifying women at risk of developing early onset PE, allowing triage of high-risk women for further investigation and risk-reducing therapy. This combination was less accurate in predicting women who have gestational hypertension or preterm birth.

Pregnancy-associated plasma protein A mRNA expression as a marker for differentiated thyroid cancer: results from a "surgical" and a "cytological" series.

PURPOSE: Pregnancy-associated plasma protein A (PAPPA) is a metalloproteinase initially described for its role during pregnancy. PAPPA regulates IGF ligands 1 (IGF1) bioavailability through the degradation of IGF-binding protein 4 (IGFBP4). After the cleavage of IGFBP4, free IGF1 is able to bind IGF1 receptors (IGF1R) triggering the downstream signaling. Recently, PAPPA expression has been linked with development of several cancers. No data have been published on thyroid cancer, yet. METHODS: We evaluated PAPPA, insulin-like growth factor (IGF1), IGF1 receptors (IGF1R) and IGF-binding protein 4 (IGFBP4) mRNA expression levels in a "Surgical series" of 94 thyroid nodules (64 cancers, 16 follicular adenomas and 14 hyperplastic nodules) and in a "Cytological series" of 80 nodules from 74 patients underwent to fine-needle aspiration cytology (FNAC). In tissues, PAPPA was also evaluated by western blot. RESULTS: We found that PAPPA expression was increased in thyroid cancer specimen at mRNA and protein levels and that, adenomas and hyperplastic nodules had an expression similar to normal tissues. When applied on thyroid cytologies, PAPPA expression was able to discriminate benign from malignant nodules contributing to pre-surgical classification of the nodules. We calculated a cut-off with a good specificity (91%) which reached 100% when combined with molecular biology. CONCLUSION: These results show that PAPPA could represent a promising diagnostic marker for differentiated thyroid cancer.