A Multimedia Strategy to Integrate Introductory Broad-Based Radiation Science Education in US Medical Schools.

US physicians in multiple specialties who order or conduct radiological procedures lack formal radiation science education and thus sometimes order procedures of limited benefit or fail to order what is necessary. To this end, a multidisciplinary expert group proposed an introductory broad-based radiation science educational program for US medical schools. Suggested preclinical elements of the curriculum include foundational education on ionizing and nonionizing radiation (eg, definitions, dose metrics, and risk measures) and short- and long-term radiation-related health effects as well as introduction to radiology, radiation therapy, and radiation protection concepts. Recommended clinical elements of the curriculum would impart knowledge and practical experience in radiology, fluoroscopically guided procedures, nuclear medicine, radiation oncology, and identification of patient subgroups requiring special considerations when selecting specific ionizing or nonionizing diagnostic or therapeutic radiation procedures. Critical components of the clinical program would also include educational material and direct experience with patient-centered communication on benefits of, risks of, and shared decision making about ionizing and nonionizing radiation procedures and on health effects and safety requirements for environmental and occupational exposure to ionizing and nonionizing radiation. Overarching is the introduction to evidence-based guidelines for procedures that maximize clinical benefit while limiting unnecessary risk. The content would be further developed, directed, and integrated within the curriculum by local faculties and would address multiple standard elements of the Liaison Committee on Medical Education and Core Entrustable Professional Activities for Entering Residency of the Association of American Medical Colleges.

Gilbert W. Beebe Symposium on 30 Years after the Chernobyl Accident: Current and Future Studies on Radiation Health Effects.

This commentary summarizes the presentations and discussions from the 2016 Gilbert W. Beebe symposium "30 years after the Chernobyl accident: Current and future studies on radiation health effects." The symposium was hosted by the National Academies of Sciences, Engineering, and Medicine (the National Academies). The symposium focused on the health consequences of the Chernobyl accident, looking retrospectively at what has been learned and prospectively at potential future discoveries using emerging 21st Century research methodologies.

MicroRNA-9 as potential biomarker for breast cancer local recurrence and tumor estrogen receptor status.

MicroRNAs (miRs) are small, non-protein coding transcripts involved in many cellular functions. Many miRs have emerged as important cancer biomarkers. In the present study, we investigated whether miR levels in breast tumors are predictive of breast cancer local recurrence (LR). Sixty-eight women who were diagnosed with breast cancer at the Lombardi Comprehensive Cancer Center were included in this study. Breast cancer patients with LR and those without LR were matched on year of surgery, age at diagnosis, and type of surgery. Candidate miRs were identified by screening the expression levels of 754 human miRs using miR arrays in 16 breast tumor samples from 8 cases with LR and 8 cases without LR. Eight candidate miRs that showed significant differences between tumors with and without LR were further verified in 52 tumor samples using real-time PCR. Higher expression of miR-9 was significantly associated with breast cancer LR in all cases as well as the subset of estrogen receptor (ER) positive cases (p = 0.02). The AUCs (Area Under Curve) of receiver operating characteristic (ROC) curves of miR-9 for all tumors and ER positive tumors are 0.68 (p = 0.02) and 0.69 (p = 0.02), respectively. In ER positive cases, Kaplan-Meier analysis showed that patients with lower miR-9 levels had significantly better 10-year LR-free survival (67.9% vs 30.8%, p = 0.02). Expression levels of miR-9 and another miR candidate, miR-375, were also strongly associated with ER status (p<0.001 for both). The potential of miR-9 as a biomarker for LR warrants further investigation with larger sample size.

Telomere length variation in normal epithelial cells adjacent to tumor: potential biomarker for breast cancer local recurrence.

A better understanding of the risk of local recurrence (LR) will facilitate therapeutic decision making in the management of early breast cancers. In the present study, we investigated whether telomere length in the normal breast epithelial cells surrounding the tumor is predictive of breast cancer LR; 152 women who were diagnosed with breast cancer at the Lombardi Comprehensive Cancer Center were included in this nested case-control study. Cases (patients had LR) and controls (patients had no LR) were matched on year of surgery, age at diagnosis and type of surgery. Telomere fluorescent in situ hybridization was used to determine the telomere length using formalin fixed paraffin-embedded breast tissues. Small telomere length variation (TLV), defined as the coefficient variation of telomere lengths among examined cells, in normal epithelial cells adjacent to the tumor was significantly associated with a 5-fold (95% confidence interval = 1.2-22.2) increased risk of breast cancer LR. When the subjects were categorized into quartiles, a significant inverse dose-response relationship was observed with lowest versus highest quartile odds ratio of 15.3 (P(trend) = 0.012). Patients who had large TLV had significantly better 10 year recurrence free survival rate compared with patients who had small TLV (80 versus 33%). The present study revealed that TLV in normal epithelial cells adjacent to tumor is a strong predictor of breast cancer LR. If confirmed by future studies, TLV in normal epithelial cells adjacent to tumor has the potential to become a promising biomarker for predicting breast cancer LR after breast conserving surgery.

Urinary estrogen metabolites and prostate cancer risk: a pilot study.

BACKGROUND: The high incidence of and few identified risk factors for prostate cancer underscore the need to further evaluate markers of prostate carcinogenesis. The aim of this pilot study was to evaluate urinary estrogen metabolites as a biomarker of prostate cancer risk. METHODS: Using a liquid chromatography-tandem mass spectrometry method, urinary concentrations of 15 estrogen metabolites were determined in 77 prostate cancer cases, 77 healthy controls, and 37 subjects who had no evidence of prostate cancer after a prostate biopsy. RESULTS: We observed an inverse association between the urinary 16-ketoestradiol (16-KE2) and 17-epiestriol (17-epiE3)--metabolites with high estrogenic activity--and prostate cancer risk. Men in the lowest quartile of 16-KE2, had a 4.6-fold risk of prostate cancer (OR=4.62, 95% CI=1.34-15.99), compared with those in the highest quartile. CONCLUSIONS: We observed modest differences in estrogen metabolite concentrations between prostate cancer patients and subjects without cancer. Larger studies with both androgen and estrogen measurements are needed to confirm these results to clarify further whether estrogen metabolites are independent biomarkers for prostate cancer risk and whether androgen/estrogen imbalance influences prostate cancer risk.

Decreased risk of squamous cell carcinoma of the head and neck in users of nonsteroidal anti-inflammatory drugs.

We evaluated the chemopreventive effect of nonsteroidal anti-inflammatory drug (NSAID) use in head and neck squamous cell carcinomas (HNSCC) by conducting a case-control study based on the administration of a standardized questionnaire to 71 incident HNSCC cases and same number of healthy controls. NSAID use was associated with a 75% reduction in risk of developing HNSCC. A significant risk reduction was noted in association with frequency of NSAID use. Restricting the analysis to aspirin users revealed a significant 90% reduction in risk of developing HNSCC. This study provides evidence for a significant reduction in the risk of developing HNSCC in users of NSAIDs, and specifically aspirin users.

Saliva: physiology and diagnostic potential in health and disease.

Saliva has been described as the mirror of the body. In a world of soaring healthcare costs and an environment where rapid diagnosis may be critical to a positive patient outcome, saliva is emerging as a viable alternative to blood sampling. In this review, we discuss the composition and various physiological roles of saliva in the oral cavity, including soft tissue protection, antimicrobial activities, and oral tissue repair. We then explore saliva as a diagnostic marker of local oral disease and focus particularly on oral cancers. The cancer theme continues when we focus on systemic disease diagnosis from salivary biomarkers. Communicable disease is the focus of the next section where we review the literature relating to the direct and indirect detection of pathogenic infections from human saliva. Finally, we discuss hormones involved in appetite regulation and whether saliva is a viable alternative to blood in order to monitor hormones that are involved in satiety.

Mutagen sensitivity, tobacco smoking and breast cancer risk: a case-control study.

UNLABELLED: Given the high incidence of breast cancer and that more than half of cases remain unexplained, the need to identify risk factors for breast cancer remains. Deficiencies in DNA repair capacity have been associated with cancer risk. The mutagen sensitivity assay (MSA), a phenotypic marker of DNA damage response and repair capacity, has been consistently shown to associate with the risk of tobacco-related cancers. METHODS: In a case-control study of 164 women with breast cancer and 165 women without the disease, we investigated the association between mutagen sensitivity and risk of breast cancer using bleomycin as the mutagen. RESULTS: High bleomycin sensitivity (>0.65 breaks per cell) was associated with an increased risk of breast cancer, with an adjusted odds ratio of 2.8 [95% confidence interval (CI) = 1.7-4.5]. Risk increased with greater number of bleomycin-induced chromosomal breaks (P(trend) = 0.01). The association between bleomycin sensitivity and breast cancer risk was greater for women who were black, premenopausal and ever smokers. Our data also suggest that bleomycin sensitivity may modulate the effect of tobacco smoking on breast cancer risk. Among women with hypersensitivity to bleomycin, ever smokers had a 1.6-fold increased risk of breast cancer (95% CI = 0.6-3.9, P for interaction between tobacco smoking and bleomycin sensitivity = 0.32). CONCLUSIONS: Increased bleomycin sensitivity is significantly associated with an increased risk of breast cancer in both pre- and postmenopausal women. Our observation that the effect of tobacco smoking on breast cancer risk may differ based on mutagen sensitivity status warrants further investigation.

Phytohemagglutinin-induced mitotic index in blood lymphocytes: a potential biomarker for breast cancer risk.

BACKGROUND: Cell proliferation is associated with the pathogenesis of cancer because it provides opportunities for accumulating genetic mutations. However, biomarkers of cell proliferation in response to environmental stimuli have not been adequately explored for breast cancer risk. METHODS: In a case-control study of 200 breast cancer patients and 360 healthy controls, we investigated the association between phytohemagglutinin (PHA)-induced mitotic index in blood lymphocyte and breast cancer risk. RESULTS: Having high mitotic index (>3.19%) was associated with an increased risk of breast cancer, with adjusted odds ratios (95% confidence interval) of 1.54 (1.03-2.30) and 2.03 (1.18-3.57) for all women and post-menopausal women, respectively. Mitotic index was correlated with some reproductive factors and body mass index in controls. CONCLUSIONS: Our data suggest increased PHA-induced mitotic index in blood lymphocytes is associated with an increased breast cancer risk and that this association may be modulated by reproductive and other hormones.

Elevated lung cancer risk is associated with deficiencies in cell cycle checkpoints: genotype and phenotype analyses from a case-control study.

Cell cycle checkpoints play critical roles in the maintenance of genomic integrity and inactivation of checkpoint genes are frequently perturbed in most cancers. In a case-control study of 299 non-small cell lung cancer cases and 550 controls in Baltimore, we investigated the association between gamma-radiation-induced G(2)/M arrest in cultured blood lymphocytes and lung cancer risk, and examined genotype-phenotype correlations between genetic polymorphisms of 20 genes involving in DNA repair and cell cycle control and gamma-radiation-induced G(2)/M arrest. The study was specifically designed to examine race and gender differences in risk factors. Our data indicated that a less efficient DNA damage-induced G(2)/M checkpoint was associated with an increased risk of lung cancer in African American women with an adjusted odds ratio (OR) of 2.63 (95% CI = 1.01-7.26); there were no statistically significant associations for Caucasians, or African American men. When the African American women were categorized into quartiles, a significant reverse trend of decreased G(2)/M checkpoint function and increased lung cancer risk was present, with lowest-vs.-highest quartile OR of 13.72 (95% CI = 2.30-81.92, p(trend) < 0.01). Genotype-phenotype correlation analysis indicated that polymorphisms in ATM, CDC25C, CDKN1A, BRCA2, ERCC6, TP53, and TP53BP1 genes were significantly associated with the gamma-radiation-induced G(2)/M arrest phenotype. This study provides evidence that a less efficient G(2)/M checkpoint is significantly associated with lung cancer risk in African American women. The data also suggested that the function of G(2)/M checkpoint is modulated by genetic polymorphisms in genes involved in DNA repair and cell cycle control.

Alertness, mood and performance rhythm disturbances associated with circadian sleep disorders in the blind.

Blind people report disturbances in alertness, mood and performance. In laboratory studies, these waking functions can only be maintained when the wake-dependent deterioration is opposed by appropriately-timed endogenous circadian rhythms. We aimed to quantify whether variations in waking function experienced by blind people living in society were dependent on the phase relationship between the sleep-wake cycle and the circadian pacemaker. The time course of alertness, mood and performance was assessed in 52 blind subjects with and without circadian rhythm disorders every 2 h for 2 days per week for 4 weeks. Sleep-wake timing and circadian phase were assessed from diaries and weekly measurements of urinary 6-sulphatoxymelatonin rhythms, respectively. In those subjects who woke at either a normal circadian phase (n = 26) or abnormally early (n = 5), alertness, mood and performance deteriorated significantly with increased time awake (P < 0.05). In 17 non-entrained ('free-running') subjects, waking function varied significantly with circadian phase such that subjects rated themselves most sleepy (P = 0.03) and most miserable (P = 0.02) when they were awake during the time of peak melatonin production. The internal phase relationship between sleep-wake behaviour and the circadian melatonin rhythm in entrained subjects contributed to predictable differences in the daily profile of alertness, mood and performance. Disruption of this phase relationship in non-entrained blind individuals with circadian rhythm sleep disorders resulted in impaired waking function during the day equivalent to that usually only experienced when awake during the night. Treatment for circadian rhythm disorders should be targeted in normalizing these phase relationships.

The nuclear envelope protein MAN1 regulates TGFbeta signaling and vasculogenesis in the embryonic yolk sac.

MAN1 is an integral protein of the inner nuclear membrane of the nuclear envelope (NE). MAN1 interacts with SMAD transcription factors, which in turn are regulated by the Transforming growth factor beta (TGFbeta) superfamily of signaling molecules. To determine the role of MAN1 in mouse development, we used a gene-trap embryonic stem cell clone to derive mice with a functional mutation in MAN1 (Man1(GT/GT)). Expression of Man1 during early development is initially low but increases at embryonic day 9.5 (E9.5). Coincident with this increase, homozygous gene-trapped Man1 (Man1(GT/GT)) embryos die by E10.5. Examination of mutant embryos and tetraploid rescue experiments reveals that abnormal yolk-sac vascularization is the probable cause of lethality. We also established embryonic stem cell lines and their differentiated derivatives that are homozygous for the Man1(GT) allele. Using these lines, we show that the Man1(GT) allele results in increased phosphorylation, nuclear localization and elevated levels of SMAD transcriptional activity, predominantly of SMAD2/3, which are regulated by the ALK5 signaling pathway. Our studies identify a previously uncharacterized role for an integral nuclear envelope protein in the regulation of yolk-sac angiogenesis by TGFbeta signaling and reveal that the NE has an essential role in regulating transcription factor activity during mouse development.