Depression, perceived stress, and distress during pregnancy and EV-associated miRNA profiles in MADRES.

BACKGROUND: MicroRNA (miRNA) circulating in plasma has been proposed as biomarkers for a variety of diseases and stress measures, including depression, stress, and trauma. However, few studies have examined the relationship between stress and miRNA during pregnancy. METHODS: In this study, we examined associations between measures of stress and depression during pregnancy with miRNA in early and late pregnancy from the MADRES cohort of primarily low-income Hispanic women based in Los Angeles, California. Extracellular-vesicle- (EV-) associated miRNA were isolated from maternal plasma and quantified using the Nanostring nCounter platform. Correlations for stress-associated miRNA were also calculated for 89 matching cord blood samples. RESULTS: Fifty miRNA were nominally associated with depression, perceived stress, and prenatal distress (raw p < 0.05) with 17 miRNA shared between two or more stress measures. Two miRNA (miR-150-5p and miR-148b-3p) remained marginally significant after FDR adjustment (p < 0.10). Fifteen PANTHER pathways were enriched for predicted gene targets of the 50 miRNA associated with stress. Clusters of maternal and neonate miRNA expression suggest a link between maternal and child profiles. LIMITATIONS: The study evaluated 142 miRNA and was not an exhaustive analysis of all discovered miRNA. Evaluations for stress, depression and trauma were based on self-reported instruments, rather than diagnostic tools. CONCLUSIONS: Depression and stress during pregnancy are associated with some circulating EV miRNA. Given that EV miRNA play important roles in maternal-fetal communication, this may have downstream consequences for maternal and child health, and underscore the importance of addressing mental health during pregnancy, especially in health disparities populations.

Extracellular vesicle-enriched miRNA profiles across pregnancy in the MADRES cohort.

MicroRNA (miRNA) circulating in plasma have been proposed as biomarkers for a variety of conditions and diseases, including complications during pregnancy. During pregnancy, about 15-25% of maternal plasma exosomes, a small size-class of EVs, are hypothesized to originate in the placenta, and may play a role in communication between the fetus and mother. However, few studies have addressed changes in miRNA over the course of pregnancy with repeated measures, nor focused on diverse populations. We describe changes in miRNA in early and late pregnancy from the MADRES cohort of primarily low-income Hispanic women based in Los Angeles, CA. miRNA derived from extracellular-vesicles (EVs) were isolated from maternal blood plasma samples collected in early and late pregnancy. In this study, we identified 64 of 130 detectable miRNA which significantly increased with gestational age at the time of collection (GA), and 26 which decreased with GA. Possible fetal sex-specific associations were observed for 30 of these 90 significant miRNA. Predicted gene targets for miRNA significantly associated with GA were identified using MirDIP and were found to be enriched for Gene Ontology categories that included energetic and metabolic processes but were underrepresented in immune-related categories. Circulating EV-associated miRNA during pregnancy are likely important for maternal-fetal communication, and may play roles in supporting and maintaining a healthy pregnancy, given the changing needs of the fetus.

Effects of air pollution on mitochondrial function, mitochondrial DNA methylation, and mitochondrial peptide expression.

Mitochondrial DNA is sensitive to damage by exogenous reactive oxygen sources, including traffic-related air pollution (TRAP). Given the important role for mitochondria in human disease, we hypothesized that prenatal air pollution exposure may be associated with mitochondrial dysfunction and that mitochondrial-derived peptides (MDPs) might protect against these effects. In in vitro studies, 24-hour exposure to nanoparticulate matter (nPM) increased oxidation of mtDNA, decreased mitochondrial consumption rate (OCR), and decreased mtDNAcn in SH-SY5Y cells. Addition of MDPs rescued these effects to varying degrees. Liver tissue taken from C57Bl/6 males exposed for 10 weeks to nPM had lower OCR, lower mtDNAcn and higher MDP levels, similar to in vitro studies. In newborn cord blood, MDP levels were positively associated with prenatal TRAP exposures. Moreover, DNA methylation of two distinct regions of the D-Loop in the mitochondria genome was associated with levels of several MDPs. Our in vitro and in vivo data indicate that TRAP can directly affect mitochondrial respiratory function and mtDNAcn. Treatment of cells with MDPs can counteract TRAP induced-effects. Lastly, we present evidence that suggests MDPs may be regulated in part by mitochondrial DNA methylation in humans.

A "turn-on" fluorescent sensor for ultrasensitive detection of melamine based on a new fluorescence probe and AuNPs.

In this study, we synthesized a new fluorescence probe which was used to detect melamine by coupling with gold nanoparticles (AuNPs). The new fluorescence probe has good optical stability and high fluorescence intensity, which can greatly improve the detection sensitivity. Compared to the traditional fluorophore, it is less dependent on the pH value. It has a very strong fluorescence emission peak at 550 nm, which has larger overlap with the absorption peak of AuNPs. When the probe incubates with the AuNPs, the fluorescence of the probe can be effectively quenched by AuNPs. Adding melamine into a probe-AuNPs mixture caused aggregation of AuNPs and released the adsorbed probe; the fluorescence intensity of the probe was recovered. By measuring the changes of the fluorescence intensity of the probe, the detection of melamine can be realized. Under optimized conditions, the linear response to melamine is in the range of 1.0 × 10(-8)-4.0 × 10(-6) mol L(-1) and lowers the detection limit down to 3.0 nmol L(-1) with the sensor. This method can detect melamine in milk and milk-based productions.

A new turn-on fluorescent probe for selective detection of glutathione and cysteine in living cells.

A fluorescent probe (N-(4-methyl-2-oxo-2H-chromen-7-yl)-2,4-dinitrobenzenesulfonamide), which exhibits high selectivity to glutathione and cysteine among amino acids including sulphur-containing methionine and metal ions, was synthesized. The experiments demonstrate that the fluorescent probe is a reliable and specific probe for glutathione and cysteine in living cells.

Population-based study of the risk of second primary contralateral breast cancer associated with carrying a mutation in BRCA1 or BRCA2.

PURPOSE: Women with breast cancer diagnosed early in life comprise a substantial portion of those tested for BRCA1/BRCA2 mutations; however, little information is available on the subsequent risks of contralateral breast cancer in mutation carriers. This study assessed the risk of subsequent contralateral breast cancer associated with carrying a BRCA1 or BRCA2 mutation. PATIENTS AND METHODS: In this nested case-control study, patients with contralateral breast cancer diagnosed 1 year or more after a first primary breast cancer (n = 705) and controls with unilateral breast cancer (n = 1,398) were ascertained from an underlying population-based cohort of 52,536 women diagnosed with a first invasive breast cancer before age 55 years. Interviews and medical record reviews were used to collect risk factor and treatment histories. All women were tested for BRCA1/BRCA2 mutations. Relative (rate ratios) and absolute (5- and 10-year cumulative) risks of developing contralateral breast cancer following a first invasive breast cancer were computed. RESULTS: Compared with noncarriers, BRCA1 and BRCA2 mutation carriers had 4.5-fold (95% CI, 2.8- to 7.1-fold) and 3.4-fold (95% CI, 2.0- to 5.8-fold) increased risks of contralateral breast cancer, respectively. The relative risk of contralateral breast cancer for BRCA1 mutation carriers increased as age of first diagnosis decreased. Age-specific cumulative risks are provided for clinical guidance. CONCLUSION: The risks of subsequent contralateral breast cancer are substantial for women who carry a BRCA1/BRCA2 mutation. These findings have important clinical relevance regarding the assessment of BRCA1/BRCA2 status in patients with breast cancer and the counseling and clinical management of patients found to carry a mutation.

Adjuvant systemic therapy for breast cancer in BRCA1/BRCA2 mutation carriers in a population-based study of risk of contralateral breast cancer.

Given the greatly elevated risks of contralateral breast cancer (CBC) observed in breast cancer patients who carry mutations in BRCA1 and BRCA2, it is critical to determine the effectiveness of standard adjuvant therapies in preventing CBC in mutation carriers. The WECARE study is a matched, case-control study of 708 women with CBC as cases and 1,399 women with unilateral breast cancer (UBC) as controls, including 181 BRCA1/BRCA2 mutation carriers. Interviews and medical record reviews provided detailed information on risk factors and breast cancer therapy. All study participants were screened for BRCA1 and BRCA2 mutations using denaturing high-performance liquid chromatography (DHPLC) to detect genetic variants in the coding and flanking regions of the genes. Conditional logistic regression was used to compare the risk of CBC associated with chemotherapy and tamoxifen in BRCA1/BRCA2 mutation carriers and non-carriers. Chemotherapy was associated with lower CBC risk both in non-carriers (RR = 0.6 [95% CI: 0.5-0.7]) and carriers (RR = 0.5 [95% CI: 0.2-1.0]; P value = 0.04). Tamoxifen was associated with a reduced CBC risk in non-carriers (RR = 0.7 [95% CI: 0.6-1.0]; P value = 0.03). We observed a similar but non-significant reduction associated with tamoxifen in mutation carriers (RR = 0.7 [95% CI: 0.3-1.8]). The tests of heterogeneity comparing carriers to non-carriers did not provide evidence for a difference in the associations with chemotherapy (P value = 0.51) nor with tamoxifen (P value = 0.15). Overall, we did not observe a difference in the relative risk reduction associated with adjuvant treatment between BRCA1/BRCA2 mutation carriers and non-carriers. However, given the higher absolute CBC risk in mutation carriers, the potentially greater impact of adjuvant therapy in reducing CBC risk among mutation carriers should be considered when developing treatment plans for these patients.

Reproductive factors and risk of contralateral breast cancer by BRCA1 and BRCA2 mutation status: results from the WECARE study.

OBJECTIVE: Reproductive factors, such as early age at menarche, late age at menopause, and nulliparity are known risk factors for breast cancer. Previously, we reported these factors to be associated with risk of developing contralateral breast cancer (CBC). In this study, we evaluated the association between these factors and CBC risk among BRCA1 and BRCA2 (BRCA1/2) mutation carriers and non-carriers. METHODS: The WECARE Study is a population-based multi-center case-control study of 705 women with CBC (cases) and 1,397 women with unilateral breast cancer (controls). All participants were screened for BRCA1/2 mutations and 181 carriers were identified. Conditional logistic regression models were used to evaluate associations between reproductive factors and CBC for mutation carriers and non-carriers. RESULTS: None of the associations between reproductive factors and CBC risk differed between mutation carriers and non-carriers. The increase in risk with younger age at menarche and decrease in risk in women with more than two full-term pregnancies seen in non-carriers were not significantly different in carriers (adjusted RRs = 1.31, 95% CI 0.65-2.65 and 0.53, 95% CI 0.19-1.51, respectively). No significant associations between the other reproductive factors and CBC risk were observed in mutation carriers or non-carriers. CONCLUSION: For two reproductive factors previously shown to be associated with CBC risk, we observed similar associations for BRCA1/2 carriers. This suggests that reproductive variables that affect CBC risk may have similar effects in mutation carriers and non-carriers.

Characterization of BRCA1 and BRCA2 deleterious mutations and variants of unknown clinical significance in unilateral and bilateral breast cancer: the WECARE study.

BRCA1 and BRCA2 screening in women at high-risk of breast cancer results in the identification of both unambiguously defined deleterious mutations and sequence variants of unknown clinical significance (VUS). We examined a population-based sample of young women with contralateral breast cancer (CBC, n=705) or unilateral breast cancer (UBC, n=1398). We identified 470 unique sequence variants, of which 113 were deleterious mutations. The remaining 357 VUS comprised 185 unique missense changes, 60% were observed only once, while 3% occurred with a frequency of >10%. Deleterious mutations occurred three times more often in women with CBC (15.3%) than in women with UBC (5.2%), whereas combined, VUS were observed in similar frequencies in women with CBC and UBC. A protein alignment algorithm defined 16 rare VUS, occurring at highly conserved residues and/or conferring a considerable biochemical difference, the majority located in the BRCA2 DNA-binding domain. We confirm a multiplicity of BRCA1 and BRCA2 VUS that occur at a wide range of allele frequencies. Although some VUS inflict chemical differences at conserved residues, suggesting a deleterious effect, the majority are not associated with an increased risk of CBC.

Oral contraceptives and postmenopausal hormones and risk of contralateral breast cancer among BRCA1 and BRCA2 mutation carriers and noncarriers: the WECARE Study.

The potential effects of oral contraceptive (OC) and postmenopausal hormone (PMH) use are not well understood among BRCA1 or BRCA2 (BRCA1/2) deleterious mutation carriers with a history of breast cancer. We investigated the association between OC and PMH use and risk of contralateral breast cancer (CBC) in the WECARE (Women's Environment, Cancer, and Radiation Epidemiology) Study. The WECARE Study is a population-based case-control study of 705 women with asynchronous CBC and 1,398 women with unilateral breast cancer, including 181 BRCA1/2 mutation carriers. Risk-factor information was assessed by telephone interview. Mutation status was measured using denaturing high-performance liquid chromatography followed by direct sequencing in all participants. Outcomes, treatment, and tumor characteristics were abstracted from medical records. Ever use of OCs was not associated with risk among noncarriers (RR = 0.87; 95% CI = 0.66-1.15) or BRCA2 carriers (RR = 0.82; 95% CI = 0.21-3.13). BRCA1 carriers who used OCs had a nonsignificant greater risk than nonusers (RR = 2.38; 95% CI = 0.72-7.83). Total duration of OC use and at least 5 years of use before age 30 were associated with a nonsignificant increased risk among mutation carriers but not among noncarriers. Few women had ever used PMH and we found no significant associations between lifetime use and CBC risk among carriers and noncarriers. In conclusion, the association between OC/PMH use and risk of CBC does not differ significantly between carriers and noncarriers; however, because carriers have a higher baseline risk of second primaries, even a potential small increase in risk as a result of OC use may be clinically relevant.

A case-control study of cyclin D1 CCND1 870A-->G polymorphism and bladder cancer.

Expression of cyclin D1 is believed to lead to progression through the G1-S cell cycle checkpoint, and both experimental and pathological evidence suggest that over-expression of this protein may increase the risk of several cancers, including transition cell carcinoma of the bladder. Two major transcripts have been described for CCND1, the gene encoding cyclin D1. CCND1 870A-->G, a common single nucleotide polymorphism in the splice donor region of exon 4, may modulate expression of these transcripts, with the A variant resulting in an increased pool of the isozyme encoded by transcript form b. A statistically significant 1.8-fold increased risk for bladder cancer among individuals possessing the A/A genotype was recently reported in a hospital-based case-control study conducted among native Japanese. We conducted a population-based case-control study of incidence of bladder cancer among non-Hispanic whites in Los Angeles County to examine the relationship between CCND1 870A-->G genotypes and bladder cancer risk. No association between the A/A genotype and risk was observed (odds ratio = 0.90, 95% confidence interval 0.60-1.33). The null association was not appreciably modified by bladder cancer risk factors, including lifetime smoking history, or by histopathologic classification.

Comparison of techniques for the successful detection of BRCA1 mutations in fixed paraffin-embedded tissue.

Genomic DNA isolated from archived paraffin-embedded tissues (PETs) has important applicability in genetic epidemiological studies. To determine the accuracy of the sequence data, using DNA derived from PET among patients with known mutations characterized from blood, we conducted a blinded factorial experiment to simultaneously examine the influence of mutation type, age of the PET, PCR product type, and Taq DNA polymerase on BRCA1 gene mutation detection. The probability of detecting sequencing artifacts was also investigated. We found that: (a) gene detection was most accurate for newer PET; (b) high fidelity Taq with shorter PCR amplicon length yielded the highest mutation detection success rate and lowest artifact rate; and (c) base substitutions were more often correctly identified than frameshift mutations or wild-type sequences. We concluded that DNA derived from PET that archived for less than 18 years can be used successfully for detecting BRCA1 gene mutations if quality control is strictly maintained.