Biofilm-derived oxylipin 10-HOME-mediated immune response in women with breast implants

This study investigates a mechanistic link of bacterial biofilm-mediated host-pathogen interaction leading to immunological complications associated with breast implant illness (BII). Over 10 million women worldwide have breast implants. In recent years, women have described a constellation of immunological symptoms believed to be related to their breast implants. We report that periprosthetic breast tissue of participants with symptoms associated with BII had increased abundance of biofilm and biofilm-derived oxylipin 10-HOME compared with participants with implants who are without symptoms (non-BII) and participants without implants. S. epidermidis biofilm was observed to be higher in the BII group compared with the non-BII group and the normal tissue group. Oxylipin 10-HOME was found to be immunogenically capable of polarizing naive CD4+ T cells with a resulting Th1 subtype in vitro and in vivo. Consistently, an abundance of CD4+Th1 subtype was observed in the periprosthetic breast tissue and blood of people in the BII group. Mice injected with 10-HOME also had increased Th1 subtype in their blood, akin to patients with BII, and demonstrated fatigue-like symptoms. The identification of an oxylipin-mediated mechanism of immune activation induced by local bacterial biofilm provides insight into the possible pathogenesis of the implant-associated immune symptoms of BII.

Exploring breast tissue microbial composition and the association with breast cancer risk factors

BACKGROUND

Microbial dysbiosis has emerged as an important element in the development and progression of various cancers, including breast cancer. However, the microbial composition of the breast from healthy individuals, even relative to risk of developing breast cancer, remains unclear. Here, we performed a comprehensive analysis of the microbiota of the normal breast tissue, which was analyzed in relation to the microbial composition of the tumor and adjacent normal tissue.

METHODS

The study cohorts included 403 cancer-free women (who donated normal breast tissue cores) and 76 breast cancer patients (who donated tumor and/or adjacent normal tissue samples). Microbiome profiling was obtained by sequencing the nine hypervariable regions of the 16S rRNA gene (V1V2, V2V3, V3V4, V4V5, V5V7, and V7V9). Transcriptome analysis was also performed on 190 normal breast tissue samples. Breast cancer risk score was assessed using the Tyrer-Cuzick risk model.

RESULTS

The V1V2 amplicon sequencing resulted more suitable for the analysis of the normal breast microbiome and identified Lactobacillaceae (Firmicutes phylum), Acetobacterraceae, and Xanthomonadaceae (both Proteobacteria phylum) as the most abundant families in the normal breast. However, Ralstonia (Proteobacteria phylum) was more abundant in both breast tumors and histologically normal tissues adjacent to malignant tumors. We also conducted a correlation analysis between the microbiome and known breast cancer risk factors. Abundances of the bacterial taxa Acetotobacter aceti, Lactobacillus vini, Lactobacillus paracasei, and Xanthonomas sp. were associated with age (p < 0.0001), racial background (p < 0.0001), and parity (p < 0.0001). Finally, transcriptome analysis of normal breast tissues showed an enrichment in metabolism- and immune-related genes in the tissues with abundant Acetotobacter aceti, Lactobacillus vini, Lactobacillus paracasei, and Xanthonomas sp., whereas the presence of Ralstonia in the normal tissue was linked to dysregulation of genes involved in the carbohydrate metabolic pathway.

CONCLUSIONS

This study defines the microbial features of normal breast tissue, thus providing a basis to understand cancer-related dysbiosis. Moreover, the findings reveal that lifestyle factors can significantly affect the normal breast microbial composition.

FAM83A is a potential biomarker for breast cancer initiation

Background

Family with sequence similarity 83 member A (FAM83A) presents oncogenic properties in several cancers including breast cancer. Recently, we reported FAM83A overexpression in normal breast tissues from women at high risk of breast cancer. We now hypothesize that FAM83A is a key factor in breast cancer initiation.

Methods

Immunohistochemical staining was used to evaluate FAM83A protein levels in both a normal breast tissue microarray (TMA, N = 411) and a breast tumor TMA (N = 349). EGFR staining and its correlation with FAM83A expression were also assessed. Lentivirus-mediated manipulation of FAM83A expression in primary and hTERT-immortalized breast epithelial cells was employed. Biological and molecular alterations upon FAM83A overexpression/downregulation and FAM83A’s interaction partners were investigated.

Results

TMA analysis revealed a 1.5-fold increase in FAM83A expression level in breast cancer cases as compared with normal breast tissues (p < 0.0001). FAM83A protein expression was directly correlated with EGFR level in both normal and breast cancer tissues. In in vitro assays, exogenous expression of FAM83A in either primary or immortalized breast epithelial cells promoted cell viability and proliferation. Additionally, Ingenuity Pathway Analysis (IPA) revealed that FAM83A overexpression in primary cells affected the expression of genes involved in cellular morphology and metabolism. Mass spectrometry analysis identified DDX3X and LAMB3 as potential FAM83A interaction partners in primary cells, while we detected FAM83A interaction with cytoskeleton reorganization factors, including LIMA1, MYH10, PLEC, MYL6 in the immortalized cells.

Conclusions

This study shows that FAM83A promotes metabolic activation in primary breast epithelial cells and cell proliferation in both primary and immortalized cells. These findings support its role in early breast oncogenesis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40364-022-00353-9.

Aberrant epigenetic and transcriptional events associated with breast cancer risk

BACKGROUND

Genome-wide association studies have identified several breast cancer susceptibility loci. However, biomarkers for risk assessment are still missing. Here, we investigated cancer-related molecular changes detected in tissues from women at high risk for breast cancer prior to disease manifestation. Disease-free breast tissue cores donated by healthy women (N = 146, median age = 39 years) were processed for both methylome (MethylCap) and transcriptome (Illumina's HiSeq4000) sequencing. Analysis of tissue microarray and primary breast epithelial cells was used to confirm gene expression dysregulation.

RESULTS

Transcriptomic analysis identified 69 differentially expressed genes between women at high and those at average risk of breast cancer (Tyrer-Cuzick model) at FDR < 0.05 and fold change ≥ 2. Majority of the identified genes were involved in DNA damage checkpoint, cell cycle, and cell adhesion. Two genes, FAM83A and NEK2, were overexpressed in tissue sections (FDR < 0.01) and primary epithelial cells (p < 0.05) from high-risk breasts. Moreover, 1698 DNA methylation changes were identified in high-risk breast tissues (FDR < 0.05), partially overlapped with cancer-related signatures, and correlated with transcriptional changes (p < 0.05, r ≤ 0.5). Finally, among the participants, 35 women donated breast biopsies at two time points, and age-related molecular alterations enhanced in high-risk subjects were identified.

CONCLUSIONS

Normal breast tissue from women at high risk of breast cancer bears molecular aberrations that may contribute to breast cancer susceptibility. This study is the first molecular characterization of the true normal breast tissues, and provides an opportunity to investigate molecular markers of breast cancer risk, which may lead to new preventive approaches.

Epigenetic control of breast cancer susceptibility

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Background: Epigenetic mechanisms such as DNA methylation are important regulators of gene expression and are frequently dysregulated early in breast carcinogenesis. The relationship between DNA methylation aberrations in normal breast tissue and breast cancer risk remains unclear. Methods: Disease-free breast tissue cores donated by 71 high-risk (Tyrer-Cuzick lifetime risk ≥20%) and 79 average-risk women were obtained from the Komen Tissue Bank and processed for whole methylome (Diagenode's MethylCap Library and single-end 75-bp sequencing on Illumina Nextseq) and whole transcriptome (Illumina Nextseq) profiling. Reads from RNA-seq data were aligned to the human genome reference, GRCh38.p12 using STAR v.2.5.2b and tested for differential gene expression using DESeq2 ver. 1.24.0. For DNA methylation data, difference of variation in deduplicated read coverage among 250-bp fixed sized bins spanning CpG islands between high- and average-risk libraries was computed as z-ratios to identify differentially methylated regions. Pathway analysis was performed using IPA v06_01. Results: We identified 1355 CpGs that were differentially methylated between high- and average-risk breast tissues (ΔZ > 0.5, FDR < 0.05). Hypomethylated CpGs were overrepresented in high-risk tissue and were found predominantly (68%) in non-coding regions. Hypermethylated CpG sites were found equally in the gene body and non-coding regions. Transcriptomic analysis identified 112 differentially expressed genes (fold change≥2, FDR < 0.05), involved in chemokines signaling, metabolism and estrogen biosynthesis. Among those, FAM83A (logfc = 2.3, FDR = 0.004) was previously described as epigenetically dysregulated in multiple cancers and transforms breast epithelial cell in vitro. Methylation-expression correlations revealed 11 epigenetically regulated genes including cellular transformation-associated BMPR1B. Two hypomethylated/upregulated long non-coding RNAs were also identified in high-risk breasts. Conclusions: This is the first gene expression/DNA methylation analysis of normal breasts from women at either high or average risk of breast cancer. Our discovery of epigenetically regulated genes associated with breast cancer risk provides an opportunity to mechanistically dissect breast cancer susceptibility and risk-associated molecular alterations. Unlike the current focus of identifying germline mutations or single nucleotide polymorphisms responsible for higher risk, our studies reveal an epigenetic mechanism, which is not discernable through simple genomic sequencing.

Abstract P1-13-03: Prospective, placebo-controlled, randomized study of metformin for breast cancer prevention in overweight/ obese women

Background: In several epidemiologic studies, the oral anti-diabetic medication metformin is associated with lower cancer incidence and diminished tumor progression. The molecular mechanism of metformin anti-cancer activity remains unclear, particularly in the preventive setting. This study investigated the effect of metformin on inflammatory and proliferative pathways in cancer-free breast tissue of overweight and obese women at high risk for breast cancer, in an effort to better understand how we might prevent obesity- related carcinogenesis in the breast.

Methods: The study cohort included 24 obese or overweight (BMI ≥ 25), postmenopausal women at increased risk for breast cancer based on family history, risk models indicating lifetime risk ≥ 20%, atypical hyperplasia, or history of DCIS or breast cancer treated over 5 years ago. Subjects were randomized to metformin (850 mg BID) or placebo for 12 months. Breast tissue core biopsy and blood collection were performed at baseline and after 12 months. Reverse Phase Protein Array (MD Anderson RPPA Core Facility) was used to determine the proteomic profiling of the breast tissue biopsies (5 replicates for each subject) at both time points. 297 unique antibodies were analyzed by Array-Pro Analyzer 6.3 then by SuperCurve_1.5.0 via SuperCurveGUI_2.1.1. All relative protein level data points were normalized for protein loading and transformed to linear values. Serum biomarkers including IGF-I, IGF-II, Leptin, IL6, IL10, adiponectin, leptin, and IGFBP3 were measured using commercial enzyme-linked immunosorbent assays (ELISA). Statistical analysis was performed using R platform. Wilcox and T tests are used to check the difference for each protein between the two time points in each group. P values below 0.05 were deemed significant.

Results: Of 24 women randomized, 18 completed the study, including 9 treated with metformin and 9 treated with placebo. Participants receiving metformin showed no significant changes in the measured serum biomarkers between pre- and post-treatment, or in comparison with the placebo group. Proteomic analysis revealed a change in both protein level as well as protein phosphorylation status in the metformin-treated group. Metformin treatment induced downregulation of regulators of cell proliferation and survival (Ets1, P=0.02; Abl1, P=0.04; Smad3, P=0.01; 14-3-3β, P=0.02; TG2, P=0.03, Beclin1, P=0.04; pT1135-RICTOR, P=0.03) in breast tissue. Several of the downregulated targets belong to two major pathways: mTOR and TGFβ. Increase in proteins involved in metabolic and AMPK pathways (PDHK1, P=0.007; pS79-ACC, P=0.02; Mnk1, P=0.02) was detected in the metformin-treated group post- treatment; however, no change was detected in the placebo-treated group.

Conclusion: Our preliminary data suggest that metformin treatment has a direct effect on breast tissue of overweight or obese, postmenopausal woman at increased risk for breast cancer by reducing pro-survival pathways, such as mTOR and TGFβ, and activating metabolic pathways, such as AMPK. Further investigation of the specific targets activated or inhibited in the cancer-free breast tissue by metformin is being performed to broaden our understanding of the protective mechanism of this antidiabetic agent.

Citation Format: Tarah Ballinger, Natascia Marino, Rana German, Jason True, Xiaoyu Lu, Sha Cao, Anna Maria Storniolo, Lida Mina. Prospective, placebo-controlled, randomized study of metformin for breast cancer prevention in overweight/ obese women [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P1-13-03.

Abstract P5-08-16: Molecular landscape of the breasts of women at high risk for breast cancer

Background: Despite advances in breast cancer diagnosis and treatment, there is a critical need to identify the determinants of breast cancer susceptibility in order to define new strategies to target cancer initiation and progression. The Susan G. Komen Tissue Bank at Indiana University (KTB), the only repository worldwide of non-malignant breast samples, can address key scientific questions by examining molecular changes, including epigenetic (DNA methylation) and transcriptomic alterations that occur in breasts of cancer-free women who are considered at high risk for developing breast cancer.

Methods: Disease-free breast tissue cores donated by 80 high-risk (Tyrer-Cuzick lifetime risk ≥20%) and 80 average-risk women were processed for whole methylome (Diagenode MeCap Seq Library and NextSeq 75_sequencing) and whole transcriptome (Illumina TruSeq Stranded mRNA HT Library followed by NextSeq 75_sequencing) profiling. The two groups were matched according to age, racial background, and menopausal status. The cohort included 131 pre-menopausal and 29 post-menopausal women (mean age 38.6, SD 12.1). Frozen breast tissue cores with either abundant or moderate epithelial cellularity were selected. For the gene expression analysis, the reads were mapped to the human genome reference, GRCh38.p12 using the alignment software STAR ver. 2.5.2b and the read counts per gene were obtained using featureCounts ver. 1.6.3. For the evaluation of the epigenetically regulated genes, we focused our investigation on two types of functionally relevant epigenetic panels: the first panel includes 666 cancer-related markers (or pan-cancer) described by Shegafinia et al 2018, and the second panel includes 16 epigenetic markers identified in normal breast tissues-derived cells as connected with breast epithelial cell differentiation*.

Results: In a preliminary analysis, we searched for transcriptomic differences in the breast tissues of high-risk women (N=43) as compared with that of matched average-risk subjects (N=48).The differential expression analysis identified 126 differentially expressed genes (DEGs, FDR&lt;0.05, fold change &gt;2), including 117 upregulated and 9 downregulated in the high-risk group. Interestingly, pathway analysis (Ingenuity Pathway Analysis, IPA v06_01) showed that most of these genes are involved with cancer. The sub-category “tumorigenesis of tissues” as defined by IPA included 71 genes. Through TCGA database analysis, using the UALCAN portal, we searched among our candidate genes for those targets that showed both overexpression and hypomethylation in breast tumors as compared with the normal breast, or vice versa, downregulation and hypermethylation in breast cancer. This pipeline allowed us to identify 17 genes potentially epigenetically regulated and involved in breast cancer susceptibility and the early phases of cancer development. Among those, two genes, FAM83A and PLA2G3, belong to a family of genes previously described as epigenetically dysregulated in multiple cancers (TCGA dataset, and Shegafinia et al 2018) and transform breast epithelial cell in vitro (FAM83A), thus reaffirming robustness of our approach in identifying genes associated with breast cancer risk

Conclusion: The discovery of epigenetically regulated genes associated with breast cancer risk will open the doors to a deeper understanding of the process of cancer initiation and progression. The present study identified 17 gene alterations, two of which are epigenetically regulated in cancer. Our findings highlight an opportunity to address molecular alterations potentially linked with breast cancer susceptibility and risk, using a unique resource of normal breast samples.

*Unpublished data by Dr. H. Nakshatri

Citation Format: Natascia Marino, Rana German, Harikrishna Nakshatri, Ashley Vode, Jun Liu, Jie Huang, Douglas B Rush, Sha Cao, Anna Maria V Storniolo. Molecular landscape of the breasts of women at high risk for breast cancer [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P5-08-16.

Abstract 4641: Metabolic reprogramming of the breast contributes to a cancer promoting milieu

In addition to the accumulation of pro-oncogenic mutations in the epithelial cells, the tumorigenic process involves the dysregulation of the interactions between the epithelial cells and their microenvironment, as well as alterations within the microenvironment itself. The latter is composed of endothelial cells, immune cells, fibroblasts, unaffected epithelium, and adipocytes. Increasing evidences support that cell transformation progresses in a potentially cancer-promoting microenvironment context, also known as field cancerization model. Therefore, it is critical to investigate changes occurring in both the epithelial compartment and the surrounding microenvironment to understand how breast cancer initiates.

In our preliminary study, we analyzed the transcriptome profile of microdissected breast tissue compartments (epithelium, stroma and adipose tissue) from tissue biopsies obtained from women who donated their histologically normal tissue two-to-five years before breast cancer diagnosis (here labeled pre-cancer), and matched healthy control donors. In the pre-cancer breast epithelium we detected a significant increase in lipid metabolism-related genes including lipases (HSL, LPL) and perilipins (PLIN1, PLIN4), which mediate the release of fatty acids from triacylglycerol storage, and ELOVL5 and ELOVL7, which generate oleic acid. Moreover, Acyl-CoA Synthetase Medium Chain Family Member 1, ACSM1, involved in the activation of lipoic acid, an essential cofactor for mitochondrial metabolism, is also upregulated in pre-cancer breast tissue. Upregulation of genes involved in metabolic activation is observed also in the stroma and adipose tissue compartments. Interestingly, the transcriptome profiling of the pre-cancer breast stroma shows the downregulation of genes coding for several immune cell markers as compared with the healthy controls. Immunohistochemical staining of CD45 confirms a significant reduction in immune cells in the pre-cancer versus matched healthy control breasts. This finding suggests the prevalence of an immune-suppressive environment in the breast long before the clinical diagnosis of breast cancer.

Understanding the changes occurring in the cancerized field is critical for elucidating 1) the involvement of microenvironment in cancer initiation 2) the role of histologically normal yet genetically altered surgical margins in risk of disease recurrence upon lumpectomy for early breast cancer diagnosis, and 3) the mechanisms of field cancerization in the contralateral breast.

Citation Format: Natascia Marino, Rana German, Xi Rao, George Sandusky, Max Jacobsen, Sha Cao, Anna Maria Storniolo. Metabolic reprogramming of the breast contributes to a cancer promoting milieu [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4641.

Abstract 5054: Transcriptional changes in breast cancer initiation

Background: Identifying the earliest stages of breast cancer carcinogenesis, present well before any clinical signs of disease, is the necessary underpinning of an effective breast cancer prevention strategy. We propose to elucidate transcriptomic changes occurring in the breast tissue during cancer initiation. by analyzing biospecimens donated by women before any clinical sign of sporadic breast tumor (here labeled “susceptible”). In the present work, we report on the transcriptome differences in the microdissected breast compartments (epithelium, stroma and fat) of susceptible versus healthy premenopausal women.

Methods: The specimens were obtained from the Susan G. Komen Tissue Bank at IU Simon Cancer Center. We compared the transcriptome profiles of breast tissues from 7 susceptible and 17 healthy premenopausal women between the age of 34 and 52 years, who were free of breast pathology at the time of donation. Donors in the two experimental groups were matched according to age, racial background and menstrual phase. Differential expression analysis was performed using EdegR. False discovery rate (FDR) was computed from p-values using the Benjamini-Hochberg procedure. Ingenuity Pathway Analysis was used to identify relevant signaling pathways. Because circulating hormones variations during menstrual cycle affect the breast epithelium gene expression, we also examined transcriptome differences independently from the menstrual phase.

Results/Discussion: We found 536 transcripts differentially expressed between the two groups (p&lt;0.05). However, only 412 changed independently from the follicular or luteal status. Among these, 130 transcripts (including 1 linRNA) were downregulated, while 282 transcripts (including 6 lincRNAs and 5 miRNAs) were upregulated in the susceptible versus healthy breasts. Among the upregulated genes, we observed three major affected pathways: 1) lipid metabolism, 2) molecular transport, and 3) energy production. When we set a more stringent cutoff (p&lt;0.05, fold change&gt; 2 and FDR&lt;0.2), only 11 genes were differentially expressed between susceptible and healthy controls; these are involved in cellular metabolism (AKR1C1, AKR1C2, and SDR16C5) and cell adhesion and cytoskeleton organization (CNTNAP2 and XIRP2). The transcription repressor ZFP57 was the only downregulated gene (fold change=-29; p=0.0002; FDR=0.09).The study will be soon corroborated with the transcriptome profiling of the other two breast compartments (stroma and fat).

Conclusion: This study shows that earliest alterations in breast cancer initiation affect metabolic pathway as well as transcriptional regulation. Interestingly, cell adhesion signaling may also be dysregulated at this early stage of cancer development. The findings will contribute to our understanding of the mechanisms of cancer initiation, as well as the identification of new therapeutic targets and thus, improvement of preventive interventions.

Citation Format: Natascia Marino, Rana German, Mariah L. Johnson, Xi Rao, Xiaoling Xuei, Jun Wan, Anna Maria V. Storniolo. Transcriptional changes in breast cancer initiation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5054.

A tunable time-resolved spontaneous Raman spectroscopy setup for probing ultrafast collective excitation and quasiparticle dynamics in quantum materials

We present a flexible and efficient ultrafast time-resolved spontaneous Raman spectroscopy setup to study collective excitation and quasi-particle dynamics in quantum materials. The setup has a broad energy tuning range extending from the visible to near infrared spectral regions for both the pump excitation and Raman probe pulses. Additionally, the balance between energy and time-resolution can be controlled. A high light collecting efficiency is realized by high numerical aperture collection optics and a high-throughput flexible spectrometer. We demonstrate the functionality of the setup with a study of the zone-center longitudinal optical phonon and hole continuum dynamics in silicon and discuss the role of the Raman tensor in time-resolved Raman scattering. In addition, we show an evidence for unequal phonon softening rates at different high symmetry points in the Brillouin zone of silicon by means of detecting pump-induced changes in the two-phonon overtone spectrum. Demagnetization dynamics in the helimagnet Cu2OSeO3 is studied by observing softening and broadening of a magnon after photo-excitation, underlining the unique power of measuring transient dynamics in the frequency domain, and the feasibility to study phase transitions in quantum materials.

Making Graphene Nanoribbons Photoluminescent

We demonstrate the alignment-preserving transfer of parallel graphene nanoribbons (GNRs) onto insulating substrates. The photophysics of such samples is characterized by polarized Raman and photoluminescence (PL) spectroscopies. The Raman scattered light and the PL are polarized along the GNR axis. The Raman cross section as a function of excitation energy has distinct excitonic peaks associated with transitions between the one-dimensional parabolic subbands. We find that the PL of GNRs is intrinsically low but can be strongly enhanced by blue laser irradiation in ambient conditions or hydrogenation in ultrahigh vacuum. These functionalization routes cause the formation of sp³ defects in GNRs. We demonstrate the laser writing of luminescent patterns in GNR films for maskless lithography by the controlled generation of defects. Our findings set the stage for further exploration of the optical properties of GNRs on insulating substrates and in device geometries.

Prostate cancer screening and incidence among men younger than age 50

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Background: Prostate cancer has long been considered as a disease of older men. However, age at diagnosis with prostate cancer has continued to decline. Since the introduction of prostate-specific antigen (PSA) test in 1986, the prostate cancer incidence rate has steadily and dramatically increased in men under age 50. This study aims to better understand demographic variations in prostate cancer screening and incidence, and clinical characteristics of prostate cancers in men under age 50.

Methods: We examined prostate cancer testing data from the Behavioral Risk Factor Surveillance System (2002, 2004, 2006, and 2008) and prostate cancer incidence data from the CDC's National Program of Cancer Registries and the NCI's Surveillance, Epidemiology, and End Results programs (2001-2006). We estimated the weighted percentage of self-reported cancer testing using SUDAAN and age-adjusted cancer incidence rates and trends using SEER-STAT. Statistical significance for trends was determined by the annual percentage change (APC) differing form zero.

Results: A total of 29,176 prostate cancer cases were identified from 2001-2006 among men under age 50. Of these, 551 (1.9%) were among men under age 40. Incidence rates remained stable from 2001-2006; however the incidence of well-differentiated tumors decreased significantly (APC=−24.7) during this time period. About 44% of men aged 40-49 years old reported having a prostate cancer test in the past two years. Prostate cancer testing and incidence rates were highest among men who were black, non-Hispanic, or lived in the northeast. Black men had more than a 2-fold increase in cancer incidence than white men.

Conclusions: The magnitude of prostate cancer testing and incidence in men under age 50 reveals significant health/public health problems in this younger population. This study demonstrates substantial regional differences in prostate cancer testing and incidence in men under age 50. It also confirms that prostate cancer testing and incidence varies by race and ethnicity. We observed a large disparity in prostate cancer incidence between blacks and whites. The incidence rate remained stable over time; the dramatic decrease occurred in well-differentiated cancers.

No significant financial relationships to disclose.

Extremely long time stability study of selected antibiotic standards

A study was conducted to investigate the quality of reference substances which were produced long before the introduction of advanced analysis and purification techniques. The quality and antimicrobial activity of WHO and EP oxytetracycline, doxycycline, colistin and spiramycin reference standards were assessed. The oldest substance was stored for 54 years in a freezer. Assay and purity tests were conducted according to Ph. Eur. 6.0. Additionally, antibacterial activity was tested with the microbiological method according to Ph. Eur. 4.0 (agar diffusion method). The results of the study show that several of the tested substances remained stable for over 40 years and one for over 50 years of storage. In most cases, the determined potency is close to the declared one, regardless of the method used (HPLC or microbiological). Composition analysis of multi-substance antibiotics (colistin and spiramycin) showed important differences compared with new reference substances. Results also indicate that no excessive degradation occurred during the entire storage period and impurity levels have not changed significantly.

Global identification of microRNA-target RNA pairs by parallel analysis of RNA ends

MicroRNAs (miRNAs) are important regulatory molecules in most eukaryotes and identification of their target mRNAs is essential for their functional analysis. Whereas conventional methods rely on computational prediction and subsequent experimental validation of target RNAs, we directly sequenced >28,000,000 signatures from the 5' ends of polyadenylated products of miRNA-mediated mRNA decay, isolated from inflorescence tissue of Arabidopsis thaliana, to discover novel miRNA-target RNA pairs. Within the set of approximately 27,000 transcripts included in the 8,000,000 nonredundant signatures, several previously predicted but nonvalidated targets of miRNAs were found. Like validated targets, most showed a single abundant signature at the miRNA cleavage site, particularly in libraries from a mutant deficient in the 5'-to-3' exonuclease AtXRN4. Although miRNAs in Arabidopsis have been extensively investigated, working in reverse from the cleaved targets resulted in the identification and validation of novel miRNAs. This versatile approach will affect the study of other aspects of RNA processing beyond miRNA-target RNA pairs.

The role of animal models in understanding feeding behavior in infants

The common evolutionary history humans share with mammals provides us with a solid basis for understanding normal oropharyngeal anatomy and functions. Physiologically, feeding is a cycle of neurophysiologic activity, where sensory input travels to the CNS which sends motor signals out to the periphery. Research with animal models is valuable because it is possible to disrupt this cycle, and develop predictive models on the causal basis of deviation from normal. Based on work with animal models, normal mammalian infant feeding behavior consists of the tongue functioning as a pump. First, the tongue assists in acquisition of milk from the nipple into the oral cavity, and then it pumps milk from the oral cavity into the valleculae prior to the pharyngeal swallow. Starting with this basic model, feeding in infant pigs was manipulated to determine the impact of variation in sensory input on behavioral output. One set of experiments suggested that chemo- or liquid sensation, in the form of milk is necessary to elicit continuing rhythmic activity. However, the rates of rhythmic suckling are intrinsic to an animal, and variation in rate cannot be entrained. Another set showed that initiation of the swallow does not purely depend on the volume of milk delivered, but also on the sensory stimulation at the mouth. These results support the idea that feeding behavior involves complex sensory integration.

Using quantitative and qualitative methods to pretest the publication. Take Charge of Your Diabetes: a Guide for Care

Quantitative and qualitative methods used to pretest the guidebook Take Charge of Your Diabetes: A Guide for Care are presented in this paper. Questionnaires were used as the quantitative method (completed by 59 diabetes educators and 301 people with diabetes) and focus groups were used as the qualitative method (3 groups composed of 22 black men and women with diabetes) to examine the relevance, purpose, content, and presentation of the Guide. Findings from between-methods triangulation supported the relevance, clarity of messages, identification of groups that would be most likely to benefit, readability, understandability, and credibility of the Guide. Specific areas that needed modification were identified. Each evaluation method provided unique data; for example, quantifiable data on intention to change behavior was provided from one method and a recommendation that diversity be maintained was provided from the other method. The relative strengths and limitations of combining quantitative and qualitative approaches are described.

Abnormal bone growth and selective translational regulation in basic fibroblast growth factor (FGF-2) transgenic mice

Basic fibroblast growth factor (FGF-2) is a pleiotropic growth factor detected in many different cells and tissues. Normally synthesized at low levels, FGF-2 is elevated in various pathologies, most notably in cancer and injury repair. To investigate the effects of elevated FGF-2, the human full-length cDNA was expressed in transgenic mice under control of a phosphoglycerate kinase promoter. Overexpression of FGF-2 caused a variety of skeletal malformations including shortening and flattening of long bones and moderate macrocephaly. Comparison by Western blot of FGF-2 transgenic mice to nontransgenic littermates showed expression of human FGF-2 protein in all major organs and tissues examined including brain, heart, lung, liver, kidney, spleen, and skeletal muscle; however, different molar ratios of FGF-2 protein isoforms were observed between different organs and tissues. Some tissues preferentially synthesize larger isoforms of FGF-2 while other tissues produce predominantly smaller 18-kDa FGF-2. Translation of the high molecular weight isoforms initiates from unconventional CUG codons and translation of the 18-kDa isoform initiates from an AUG codon in the FGF-2 mRNA. Thus the Western blot data from the FGF-2 transgenic mice suggest that tissue-specific expression of FGF-2 isoforms is regulated translationally.

Association of lifestyle and personality characteristics with blood pressure and hypertension: a cross-sectional study in the elderly

The association between certain lifestyle and personality characteristics and blood pressure in the elderly was assessed in a cross-sectional study of 843 independent living 60-87 year old volunteers. They comprised 338 women and 505 men of whom 35 and 30% respectively were being treated with antihypertensive drugs. Among untreated volunteers, 28% of women and 28% of men had systolic blood pressure greater than 160 or diastolic blood pressure greater than 95. Isolated systolic hypertension was found in 20% of untreated women and 14% of untreated men. Lifestyle factors and personality characteristics associated with blood pressure were similar to those described in younger adult populations, although there were some differences related to gender and whether subjects were being treated for hypertension. Stepwise multiple regression showed that higher blood pressure was associated with greater body mass index (BMI), alcohol intake and coffee drinking and measures of irritability. Increased physical activity, and high values for measures of suspicion and extraversion were negatively related to blood pressure. Age was positively related to systolic, but not to diastolic blood pressure. The presence of hypertension was significantly associated with self-reports of raised cholesterol, diabetes or angina, as well as past history of heart failure, heart attack or stroke. Thus, in this elderly free-living population blood pressures are still significantly associated with behavioural characteristics which could be further investigated as an alternative or adjunct to antihypertensive therapy.

Postural fall in blood pressure in the elderly in relation to drug treatment and other lifestyle factors

In a study of 843 independent-living men and women aged between 60 and 87 in Perth, Western Australia, stepwise multiple regression, after correction for initial levels of systolic blood pressure, showed that postural fall in systolic blood pressure was positively related to alcohol intake of more than 20 ml/day, the use of sleeping tablets and higher levels of anxiety on the Spielberger state-trait scale, and negatively related to body mass index. Postural fall in blood pressure was not significantly related to treatment for hypertension, age, sex, patterns of usual physical activity, tea or coffee drinking, or the diagnosis of diabetes mellitus. This analysis is the first to examine the relationship between lifestyle factors and the magnitude of the fall in systolic blood pressure on standing after adjustment for the association between the change in a variable and its initial level. Our analysis suggests the need for further study of the possible role of lifestyle factors such as the use of sleeping tablets and alcohol in postural hypotension in the elderly.

A randomised double blind comparison of enalapril versus hydrochlorothiazide in elderly hypertensives

To assess the suitability of therapy with an angiotensin-converting enzyme inhibitor for older hypertensives, a randomised double blind two group comparison of enalapril (10 to 40 mg daily) with hydrochlorothiazide (25 to 100 mg daily) was carried out in 32 untreated and independently living subjects aged 63 to 82 years with pressures on screening greater than 100 mmHg diastolic or greater than 180 mmHg systolic and after two weeks on placebo greater than 90 mmHg diastolic or greater than 160 mmHg systolic. Twenty-five subjects completed the ten weeks of active treatment with the majority in both groups reaching target blood pressures. Four subjects on enalapril and three on hydrochlorothiazide withdrew because of side effects. Eighteen of the 32 patients volunteered troublesome symptoms they attributed to therapy, which in some instances were alleviated by reductions in drug dosage. Small but significant falls in plasma potassium and sodium and increases in plasma urea and uric acid were seen on hydrochlorothiazide only. It was concluded that although in most cases good blood pressure control can be achieved by enalapril with some advantages over other drugs in the elderly, the potential for adverse effects remains significant. Halving usual starting doses of this and other antihypertensives may help to minimise problems in older subjects.

Growth allometry of craniomandibular muscles, tendons, and bones in the laboratory rat (Rattus norvegicus): relationships to oromotor maturation and biomechanics of feeding

This study addressed the problem of how growth of craniomandibular muscles, tendons, and bones influences the acquisition of oromotor skills and biomechanics of feeding in the laboratory rat (Rattus norvegicus). Rats representing a 6.6-fold size range were dissected, and muscles, tendons, and mandibles were weighed. Cross-sectional areas of tendons and bones providing attachment surfaces for muscles were estimated. Ontogenetic scaling of craniomandibular muscles, tendons, and bones was described by using linear regression models, and departures from size-required compensations were used to characterize changes in oromotor function. A two-dimensional model was developed which permitted calculation of mechanical advantages of four masticatory muscles; the model was used to show how mandibular growth and tooth eruption influence the biomechanics of rat feeding. Relative to mandible weight, most jaw muscles scaled either isometrically or positively, tendon cross-sectional areas scaled isometrically or negatively, and bone surfaces scaled negatively. With the exception of the superficial masseter and internal pterygoid muscles, mechanical advantages did not change significantly during mandible growth. Growth patterns of craniomandibular muscles, tendons, and bones contribute significantly to changes in morphology and oromotor function.

Ethylene Propylene Terpolymers

The general technological properties of a polymer are closely related to its molecular structure. It is, therefore, important to know polymerization methods by which to produce reproducible polymers with controlled structures. Use of several monomers in copolymerization significantly increases the difficulty of this problem, but in the end it leads to a much wider spectrum of raw materials. In addition to variations caused by changes in molecular weight and in molecular weight distribution the nature of copolymers may be altered by changing the composition of the monomer mixture and the way monomers are distributed in the polymer chain. Use of Ziegler-Natta catalysts has already given a multiplicity of materials composed of ethylene and propylene: random copolymers are particularly interesting as rubbers. Introduction of a third component to give unsaturation in the terpolymer, so that this may be vulcanized with sulfur and accelerators, has greatly increased the possible areas of application for these polymers. Utility of a diene as the third component to give EPT's which can be used as general purpose rubbers depends on its price, the ease with which it copolymerizes through one double bond, its influence on the velocity or steric course of the ethylene-propylene copolymerization, vulcanization characteristics of the resulting terpolymers, and finally on the technological properties of the vulcanizates. The amount of copolymerized termonomer should be limited to retain the advantageous chemical and physical properties of the original ethylene-propylene copolymers. However very low degrees of unsaturation limit the sulfur and accelerator system, the characteristics of which depend strongly on the structure of the terpolymer as well as on the nature and form of the vulcanization agent. It is therefore essential to have a thorough understanding of this multiple interdependency for optimal application of the materials. We describe here reproducible procedures for production of terpolymers with controlled structures, and the course of vulcanization of the products in relation to terpolymer structure. We shall describe methods, based on these investigations, which may be applied for control of the vulcanization characteristics of the polymers.