Maternal engineered nanomaterial inhalation during gestation alters the fetal transcriptome.

BACKGROUND: The integration of engineered nanomaterials (ENM) is well-established and widespread in clinical, commercial, and domestic applications. Cardiovascular dysfunctions have been reported in adult populations after exposure to a variety of ENM. As the diversity of these exposures continues to increase, the fetal ramifications of maternal exposures have yet to be determined. We, and others, have explored the consequences of ENM inhalation during gestation and identified many cardiovascular and metabolic outcomes in the F1 generation. The purpose of these studies was to identify genetic alterations in the F1 generation of Sprague-Dawley rats that result from maternal ENM inhalation during gestation. Pregnant dams were exposed to nano-titanium dioxide (nano-TiO2) aerosols (10 ± 0.5 mg/m3) for 7-8 days (calculated, cumulative lung deposition = 217 ± 1 µg) and on GD (gestational day) 20 fetal hearts were isolated. DNA was extracted and immunoprecipitated with modified chromatin marks histone 3 lysine 4 tri-methylation (H3K4me3) and histone 3 lysine 27 tri-methylation (H3K27me3). Following chromatin immunoprecipitation (ChIP), DNA fragments were sequenced. RNA from fetal hearts was purified and prepared for RNA sequencing and transcriptomic analysis. Ingenuity Pathway Analysis (IPA) was then used to identify pathways most modified by gestational ENM exposure. RESULTS: The results of the sequencing experiments provide initial evidence that significant epigenetic and transcriptomic changes occur in the cardiac tissue of maternal nano-TiO2 exposed progeny. The most notable alterations in major biologic systems included immune adaptation and organismal growth. Changes in normal physiology were linked with other tissues, including liver and kidneys. CONCLUSIONS: These results are the first evidence that maternal ENM inhalation impacts the fetal epigenome.

Percentage of free serum prostate-specific antigen as a predictor of pathologic features of prostate cancer in a screening population.

OBJECTIVES: Measurement of the percentage of free prostate-specific antigen (%FPSA) in serum can improve the specificity of prostate cancer screening. We evaluated the ability of %FPSA to predict pathologic features of screen-detected clinically localized prostate cancer. METHODS: We evaluated the correlation between %FPSA in serum before cancer diagnosis and the pathologic features of the cancers detected in 108 men with clinically localized prostate cancer who were treated with radical prostatectomy and for whom complete embedding of the radical prostatectomy specimen was performed. Ninety-seven men (90%) had a previous negative screening evaluation before prostate cancer was detected. RESULTS: There was a negative correlation of %FPSA with penetration of cancer through the prostatic capsule, cancerous surgical margins, Gleason score, percentage of cancer in the gland, and tumor volume (r = -0.2 to -0.4). After controlling for other preoperative predictors, %FPSA predicted capsular penetration (adjusted odds ratio [OR] 1.6, 95% confidence interval [CI] 1.1 to 2.4, for each 5% decrease in %FPSA) and cancer volume 0.5 cc or greater (adjusted OR 1.6, 95% CI 1.1 to 2.3). Preoperative %FPSA also predicted possibly harmless cancer (OR 1.5, 95% CI 1.1 to 2.2, for each 5% increase in %FPSA). CONCLUSIONS: In a select group of men for whom cancer was detected early via screening, a lower %FPSA in serum suggests a potentially more threatening cancer. This information may aid patients and clinicians in making more informed decisions about the management of prostate cancer, such as selecting patients for watchful waiting. However, more research is needed to determine the performance characteristics of %FPSA in clinical practice.

Cleavage and 3H-uridine incorporation in bovine embryos of high in vitro developmental potential.

The timing of genome activation in bovine embryos is still not well defined. The objective of this study was therefore to investigate transcription in bovine embryos with a high potential to develop in culture after in vitro fertilization, by examining, autoradiographically, their incorporation of 3H-uridine. Initial experiments determined that developmental potential in vitro could be related to the time of first division of the zygote. Embryos that completed their first cleavage within 30 hours of exposure to sperm were more likely to develop into blastocysts (65.7%) and to hatch (50.9%). Using such embryos, it was found that 10 of 12 8-cell and all 11 4-cell stage embryos were labeled after a 2-4-hr exposure to 3H-Uridine. Among 2-cell stage embryos, 0 of 23, 3 of 17, 8 of 15, and 3 of 4 were labeled after exposure to 3H-uridine of 2, 4, 7, and 10 hr, respectively. Treatment with alpha-amanatin (10-100 micrograms/ml) blocked 3H-uridine incorporation but did not inhibit cleavage during the first 4 cell cycles. It was concluded that transcription occurs as early as the 2-cell stage in bovine embryos in vitro but is not critical to the first four cell cycles.

Prospective characterization of pathological features of prostatic carcinomas detected via serum prostate specific antigen based screening.

PURPOSE: Many small (less than 0.5 cc), well differentiated, organ-confined prostate carcinomas remain clinically undetected during the life of the patient and are identified only at postmortem examination. Thus, these cancers are often called latent or autopsy cancers. There is concern that serum prostate specific antigen (PSA) based screening may preferentially detect these cancers. There are limited prospective data concerning the pathological features of carcinomas of the prostate detected in a screening program. We determined if prostatic carcinomas detected via PSA based screening resembled autopsy cancers. MATERIALS AND METHODS: We assessed the pathological features of carcinomas in 100 consecutive, completely embedded radical prostatectomy specimens from men whose cancer was detected in a PSA based screening program. The tumors were evaluated for pathological stage, surgical margin status, Gleason histological grade and intraglandular tumor extent (morphometrically quantified as percentage carcinoma and tumor volume). RESULTS: Of 100 carcinomas 68 (68%) were larger than 0.5 cc in volume (mean 1.7, range 0.1 to 10.7). Mean amount of carcinoma in the surgical specimen was 10.3% (range 0.1 to 41.6). Of the 100 carcinomas 94 had a Gleason score of 5 to 8 (mean 5.7) and only 6 (6%) were well differentiated (Gleason score of 4 or less). Locally advanced disease was noted in 41 cases (41%) as judged by the presence of extracapsular carcinoma and/or cancerous surgical margins. CONCLUSIONS: We concluded that the pathological features of most prostatic carcinomas detected via PSA based screening do not resemble those of autopsy cancers, and that most prostatic cancers detected in screening programs are likely to be clinically important.

Nucleolar and mitochondrial morphology in bovine embryos reconstructed by nuclear transfer.

The nucleolar and mitochondrial morphology of developing reconstructed bovine nuclear transfer (NT) embryos and stage-matched in vivo-produced control embryos were examined under the electron microscope. Each reconstructed embryo at the one-cell (n = 12), two-cell (n = 5), three-cell (n = 3), four-cell (n = 5), 5-8-cell (n = 5) and blastocyst (n = 3) stages was produced by fusion of a 16-32-cell-stage blatomere with an aged enucleated bovine oocyte. The normal and reconstructed embryos showed similar mitochondrial morphology. However, NT embryos produced several pleiomorphic forms not seen in controls, and were more heterogeneous at early stages of development. Control embryos exhibited nucleolar features considered indicative of rRNA synthesis from the eight-cell stage onwards. In contrast, the NT embryos presented nucleoli with morphology consistent with rRNA synthesis in all embryos examined, except in the three-cell and in two of the five four-cell embryos. From this nucleolar morphology, it was concluded that nuclear reprogramming does not occur immediately following nuclear transfer, but occurs gradually over the first two or three cell cycles.