SLC25A51 decouples the mitochondrial NAD+/NADH ratio to control proliferation of AML cells.

SLC25A51 selectively imports oxidized NAD+ into the mitochondrial matrix and is required for sustaining cell respiration. We observed elevated expression of SLC25A51 that correlated with poorer outcomes in patients with acute myeloid leukemia (AML), and we sought to determine the role SLC25A51 may serve in this disease. We found that lowering SLC25A51 levels led to increased apoptosis and prolonged survival in orthotopic xenograft models. Metabolic flux analyses indicated that depletion of SLC25A51 shunted flux away from mitochondrial oxidative pathways, notably without increased glycolytic flux. Depletion of SLC25A51 combined with 5-azacytidine treatment limits expansion of AML cells in vivo. Together, the data indicate that AML cells upregulate SLC25A51 to decouple mitochondrial NAD+/NADH for a proliferative advantage by supporting oxidative reactions from a variety of fuels. Thus, SLC25A51 represents a critical regulator that can be exploited by cancer cells and may be a vulnerability for refractory AML.

Flotillin-1 palmitoylation is essential for its stability and subsequent tumor promoting capabilities.

Flotillin-1 contributes to invasion and metastasis in triple negative breast cancer (TNBC) and is modified post-translationally through palmitoylation. Palmitoylation, the process of conjugating palmitoyl-CoA to proteins, plays an essential role in protein stability and trafficking. Thus far, there has not been any investigation into the role of flotillin-1 palmitoylation in the context of metastasis in vivo. To address the role of flotillin-1 palmitoylation in metastasis, MDA-MB-231 cells expressing palmitoylation defective flotillin-1 constructs were used as models. Compared to flotillin-1 WT expressing tumors, flotillin-1 palmitoylation defective displayed abrogated tumor progression and lung metastasis in vivo in both spontaneous and experimental models. Further mechanistic investigation led to the identification of zDHHC5 as the main palmitoyl acyltransferase responsible for palmitoylating endogenous flotillin-1. Modulation of flotillin-1 palmitoylation status through mutagenesis, zDHHC5 silencing, and 2-bromopalmitate inhibition all resulted in the proteasomal degradation of flotillin-1 protein. To assess if flotillin-1 palmitoylation can be inhibited for potential clinical relevance, we designed a competitive peptide fused to a cell penetrating peptide sequence, which displayed efficacy in blocking flotillin-1 palmitoylation in vitro without altering palmitoylation of other zDHHC5 substrates, highlighting its specificity. Additionally, TNBC xenograft tumor models expressing a doxycycline inducible flotillin-1 palmitoylation inhibiting peptide displayed attenuated tumor growth and lung metastasis. Collectively, these results reveal a novel palmitoylation dependent mechanism which is essential for the stability of flotillin-1 protein. More specifically, disruption of flotillin-1 palmitoylation through mutagenesis or competitive peptide promoted flotillin-1 protein degradation, subsequently impeding its tumor promoting and metastasis-inducing effects in TNBC tumor models.

Dynamics of SLC25A51 reveal preference for oxidized NAD+ and substrate led transport.

SLC25A51 is a member of the mitochondrial carrier family (MCF) but lacks key residues that contribute to the mechanism of other nucleotide MCF transporters. Thus, how SLC25A51 transports NAD+ across the inner mitochondrial membrane remains unclear. To elucidate its mechanism, we use Molecular Dynamics simulations to reconstitute SLC25A51 homology models into lipid bilayers and to generate hypotheses to test. We observe spontaneous binding of cardiolipin phospholipids to three distinct sites on the exterior of SLC25A51's central pore and find that mutation of these sites impairs cardiolipin binding and transporter activity. We also observe that stable formation of the required matrix gate is controlled by a single salt bridge. We identify binding sites in SLC25A51 for NAD+ and show that its selectivity for NAD+ is guided by an electrostatic interaction between the charged nicotinamide ring in the ligand and a negatively charged patch in the pore. In turn, interaction of NAD+ with interior residue E132 guides the ligand to dynamically engage and weaken the salt bridge gate, representing a ligand-induced initiation of transport.

CRISPR metabolic screen identifies ATM and KEAP1 as targetable genetic vulnerabilities in solid tumors.

Cancer treatments targeting DNA repair deficiencies often encounter drug resistance, possibly due to alternative metabolic pathways that counteract the most damaging effects. To identify such alternative pathways, we screened for metabolic pathways exhibiting synthetic lethality with inhibition of the DNA damage response kinase Ataxia-telangiectasia-mutated (ATM) using a metabolism-centered Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/Cas9 library. Our data revealed Kelch-like ECH-associated protein 1 (KEAP1) as a key factor involved in desensitizing cancer cells to ATM inhibition both in vitro and in vivo. Cells depleted of KEAP1 exhibited an aberrant overexpression of the cystine transporter SLC7A11, robustly accumulated cystine inducing disulfide stress, and became hypersensitive to ATM inhibition. These hallmarks were reversed in a reducing cellular environment indicating that disulfide stress was a crucial factor. In The Cancer Genome Atlas (TCGA) pan-cancer datasets, we found that ATM levels negatively correlated with KEAP1 levels across multiple solid malignancies. Together, our results unveil ATM and KEAP1 as new targetable vulnerabilities in solid tumors.

Histone H2AX promotes metastatic progression by preserving glycolysis via hexokinase-2.

Genomic stability is essential for organismal development, cellular homeostasis, and survival. The DNA double-strand breaks are particularly deleterious, creating an environment prone to cellular transformation and oncogenic activation. The histone variant H2AX is an essential component of the nucleosome responsible for initiating the early steps of the DNA repair process. H2AX maintains genomic stability by initiating a signaling cascade that collectively functions to promote DNA double-strand breaks repair. Recent advances have linked genomic stability to energetic metabolism, and alterations in metabolism were found to interfere with genome maintenance. Utilizing genome-wide transcripts profiling to identify differentially-expressed genes involved in energetic metabolism, we compared control and H2AX-deficient metastatic breast cancer cell lines, and found that H2AX loss leads to the repression of key genes regulating glycolysis, with a prominent effect on hexokinase-2 (HK2). These observations are substantiated by evidence that H2AX loss compromises glycolysis, effect which was reversed by ectopic expression of HK2. Utilizing models of experimental metastasis, we found that H2AX silencing halts progression of metastatic breast cancer cells MDA-MB-231. Most interestingly, ectopic expression of HK2 in H2AX-deficient cells restores their metastatic potential. Using multiple publicly available datasets, we found a significantly strong positive correlation between H2AX expression levels in patients with invasive breast cancer, and levels of glycolysis genes, particularly HK2. These observations are consistent with the evidence that high H2AX expression is associated with shorter distant metastasis-free survival. Our findings reveal a role for histone H2AX in controlling the metastatic ability of breast cancer cells via maintenance of HK2-driven glycolysis.

Systematic Review and Meta-Analysis of the Effect of Nutrients on Blood Lead Levels in Pregnancy.

OBJECTIVE: To synthesize experimental and nonexperimental research on the relationship between nutrients and blood lead levels in pregnant women. We also performed a meta-analysis on a subgroup of studies on calcium and blood lead levels. DATA SOURCES: PubMed, Embase, and CINAHL databases were searched in July 2019. STUDY SELECTION: We included articles published in English in any year that reported the results of experimental or observational studies on the effect of nutrients on blood lead levels in pregnancy. DATA EXTRACTION: Three nurse reviewers extracted data and appraised the studies using tools from the Joanna Briggs Institute. DATA SYNTHESIS AND META-ANALYSIS: We included 28 studies from 16 countries. Study authors examined 14 distinct nutrients, with calcium being the most frequent. The metaregression included nine analyses of the effect of calcium on blood lead levels and showed a small but significant inverse relationship. The quality of evidence for the effect of calcium on lead levels was high. Eleven analyses were related to the effect of iron on blood lead levels. The quality of evidence was high, and we found mostly negative associations between iron intake and blood lead levels. The quality of evidence for the remaining nutrients was moderate, with few significant findings. CONCLUSION: Targeted nutritional interventions may be beneficial for pregnant women with current lead exposure or a history of elevated lead levels, particularly those with calcium- or iron-deficient diets. More rigorously designed studies are needed in this area.

Inflammatory mediators in intra-abdominal sepsis or injury - a scoping review.

INTRODUCTION: Inflammatory and protein mediators (cytokine, chemokine, acute phase proteins) play an important, but still not completely understood, role in the morbidity and mortality of intra-abdominal sepsis/injury. We therefore systematically reviewed preclinical and clinical studies of mediators in intra-abdominal sepsis/injury in order to evaluate their ability to: (1) function as diagnostic/prognostic biomarkers; (2) serve as therapeutic targets; and (3) illuminate the pathogenesis mechanisms of sepsis or injury-related organ dysfunction. METHODS: We searched MEDLINE, PubMed, EMBASE and the Cochrane Library. Two investigators independently reviewed all identified abstracts and selected articles for full-text review. We included original studies assessing mediators in intra-abdominal sepsis/injury. RESULTS: Among 2437 citations, we selected 182 studies in the scoping review, including 79 preclinical and 103 clinical studies. Serum procalcitonin and C-reactive protein appear to be useful to rule out infection or monitor therapy; however, the diagnostic and prognostic value of mediators for complications/outcomes of sepsis or injury remains to be established. Peritoneal mediator levels are substantially higher than systemic levels after intra-abdominal infection/trauma. Common limitations of current studies included small sample sizes and lack of uniformity in study design and outcome measures. To date, targeted therapies against mediators remain experimental. CONCLUSIONS: Whereas preclinical data suggests mediators play a critical role in intra-abdominal sepsis or injury, there is no consensus on the clinical use of mediators in diagnosing or managing intra-abdominal sepsis or injury. Measurement of peritoneal mediators should be further investigated as a more sensitive determinant of intra-abdominal inflammatory response. High-quality clinical trials are needed to better understand the role of inflammatory mediators.

Credentialing Public Health Nurses: Current Issues and Next Steps Forward.

OBJECTIVES: The purpose of this descriptive, cross-sectional study was to identify Public Health Nurses' (PHN) perceived motivators and barriers to seeking PHN board certification. DESIGN AND SAMPLE: In collaboration with the Quad Council of Public Health Nursing Organizations, PHNs from across the United States were invited to complete the PHN Certification Survey, a 14-item online questionnaire. MEASURES: A total of 912 surveys were completed. RESULTS: PHNs were motivated to seek PHN board certification by three overarching categories: professional competence, personal satisfaction, and financial incentives. Frequently cited barriers to certification were lack of knowledge of certification opportunities, being unaware of eligibility criteria, cost, perceived lack of value/reward by employer, and preparation time. CONCLUSIONS: Demonstrating a highly educated, competent, and reliable PHN workforce can only be achieved through ongoing professional development and credentialing. PH stakeholders (i.e., PHN organizations, employers, PHNs, etc.) need a strategic approach to address the main barriers to certification identified in this study (a) awareness of certification and eligibility criteria, and (b) recognition of the credential by employers. In addition, research on the relationship between PHN credentialing and population health outcomes is essential.

Five-year summary of COMLEX-USA level 2-PE examinee performance and survey data.

The authors present data on examination format and examinee demographics, performance, and survey results for the Comprehensive Osteopathic Medical Licensing Examination-USA Level 2-Performance Evaluation (COMLEX-USA Level 2-PE) from the first five testing cycles (2004-2005 to 2008-2009). First-time examinees in the 2004-2005 testing cycle had a pass rate of 96.1%, compared with a pass rate of 94.7% for first-time examinees in the 2008-2009 testing cycle. Pass rates were fairly consistent across all testing cycles. Based on postexamination survey results from all testing cycles, the majority of examinees reported that the cases in COMLEX-USA Level 2-PE represented appropriate challenges for fourth-year osteopathic medical students. The majority of examinees also reported that comprehensive standardized patient-based examinations and exercises were administered through their colleges of osteopathic medicine. In addition, survey results indicated overall satisfaction among examinees with the administration of COMLEX-USA Level 2-PE.

Quality assurance best practices for simulation-based examinations.

Whether used for formative or summative evaluation, health professions schools, residency programs, continuing medical education programs, and specialty boards using simulation-based assessment must consider quality assurance methods to ensure reliable results. This article addresses the content, training, and administrative protocols that are necessary for findings based on valid, reliable, and fair assessments.

Impact of physicians' personal discomfort and patient prognosis on discussion of fertility preservation with young cancer patients.

OBJECTIVE: This study sought to determine if physician's personal discomfort with the topic of FP and a patient's prognosis would have an impact on the likelihood of discussing FP with cancer patients. METHODS: Data from larger studies of qualitative semi-structured interviews with pediatric and adult oncologists were analyzed using grounded theory and crystallizing immersion method to examine the themes of "personal comfort" and "patient prognosis" in relation to discussion. RESULTS: Results showed that, across both physician types, the majority of respondents' personal comfort with the topic of FP was related to the likelihood of discussion. Personal discomfort manifested as: (a) lack of knowledge; (b) language/cultural barriers; (c) perception that subject of FP adds more stress to situation; (d) general uncertainty about success of FP methods. Data also indicate physicians do not feel discussions are appropriate for patients with poor prognosis. CONCLUSION: Despite the ASCO guidelines suggesting physicians should discuss FP with all patients, the majority of physicians are not following these guidelines. PRACTICE IMPLICATIONS: Improved training on recognition of such biases and communication strategies may improve the quality and frequency of such discussions. Involving the entire healthcare team in discussions may alleviate the need for physicians to have sole responsibility.

Attitudes of high-risk women toward preimplantation genetic diagnosis.

OBJECTIVE: To explore the knowledge and attitudes toward preimplantation genetic diagnosis (PGD) of women who have been personally affected by hereditary breast and ovarian cancer. DESIGN: A 33-item quantitative survey covering five domains, including demographics, knowledge and attitudes about PGD, usage of PGD, and informational needs. SETTING: Attendees of a national conference for individuals and families affected by hereditary breast and ovarian cancer participated in the survey. PATIENT(S): Not applicable. INTERVENTION(S): Not applicable. MAIN OUTCOME MEASURE(S): Frequencies and proportions were summarized for all variables, and Fisher's exact tests were conducted to test association between two discrete variables. RESULT(S): Of the women surveyed, only 32% had ever heard of PGD before taking the survey. None of the women surveyed had actually used PGD, and 44% believed they would not use it in the future. However, 57% of attendees believed that PGD was an acceptable option for high-risk individuals, and 74% believed that high-risk individuals should be given information about PGD. CONCLUSION(S): Health care professionals who serve cancer patients should consider incorporating information about PGD into patient education. Further research is needed to survey physicians and genetic counselors about their knowledge and opinions of PGD.

Oncology social workers' perceptions of barriers to discussing fertility preservation with cancer patients.

Infertility is a common result of cancer treatment; however, opportunities exist that allow patients to preserve their fertility prior to treatment. Evidence suggests health care providers, including social workers, do not consistently discuss this topic with patients. This study used a qualitative, cross-sectional design using a focus group and in-depth interviews to explore knowledge, attitudes, barriers, and behaviors related to social workers' discussion of fertility preservation with cancer patients. Factors that influence the discussion of fertility preservation among social workers include: (1) Knowledge (e.g., Fertility Preservation Resources); (2) Attitudes (e.g., Cost, Perceived Role, Comfort Level, Fertility Preservation Discussion Difficulty/Priority); (3) Barriers (e.g., Cost, Urgency to start Treatment/Time, Patient Factors, Physician Attitudes/Beliefs); (4) Behaviors; and (5) Suggestions. Results show social workers are not typically discussing fertility preservation methods with patients; however, they may be in an ideal position to facilitate the conversation between the physician and the patient. There is a strong need to develop educational interventions aimed at oncology social workers, to help facilitate discussions with patients.

Barriers to fertility preservation among pediatric oncologists.

OBJECTIVE: Limited research has been conducted on the extent to which fertility preservation is discussed by pediatric oncologists with patients and less is known about the discussion content. This study sought to examine factors that may influence the discussion with pediatric cancer patients and families. METHODS: Qualitative data were collected using open-ended, in-depth interviews with 24 pediatric oncologists in Florida at 13 children's cancer centers, representing 87% of the centers in the state. RESULTS: Providers practiced between 0.5 and 35 years, treated most types of pediatric cancers, and most were board certified in pediatric hematology/oncology. The main factors associated with a discussion of fertility preservation options were: (1) physician factors that contribute to communication issues with FP discussion (e.g., awareness and sense of comfort in discussing issues, perceptions of the priority); (2) parent factors (e.g., receptiveness and cultural background); (3) patient factors (e.g., receptiveness and age); and (4) institutional factors (e.g., referral sites and practice guidelines). CONCLUSIONS: Pediatric oncologists may benefit from education about fertility preservation options for pediatric cancer patients, particularly females. PRACTICE IMPLICATIONS: Training on how to address parents' and patients' emotions, culture, and other factors may also promote the discussion. Although guidelines have been established, barriers related to availability and affordability of resources must also be addressed.

Oncology nurses' perceptions of barriers to discussion of fertility preservation with patients with cancer.

Infertility is a common result of cancer treatment; however, opportunities exist for patients to preserve fertility prior to treatment. Recent evidence suggests that healthcare providers, including nurses, do not consistently discuss fertility preservation (FP) with patients. This qualitative, cross-sectional pilot study used a focus group and in-depth interviews to explore knowledge, attitudes, and practice behaviors related to nurses' discussion of FP with patients with cancer. Results indicate that only half of the nurses discuss FP methods with patients, even though most believe that having discussions with patients about fertility is part of their role. Factors associated with the discussion of FP among nurses included (a) knowledge (FP procedures, fertility institutes and clinics, resources for patients, and practice guidelines), (b) attitudes (difficulty finding facilities, time constraints, role, comfort level, ethical issues, financial considerations, and patient characteristics), and (c) behaviors (patient initiation, physician behaviors, patient characteristics, and timing). Discussion should be stimulated among nurses about the role of nurses in the FP discussion, and educational interventions and practice guidelines should be developed that are aimed at oncology nurses to help facilitate discussions with patients.

Pediatric oncology nurses' attitudes related to discussing fertility preservation with pediatric cancer patients and their families.

This study explores nurses' attitudes toward the discussion of fertility preservation (FP) with pediatric cancer patients and their families. A cross-sectional survey was administered to attendees of a pediatric oncology conference. Of the 115 nurses who responded and comprised the study sample, most reported discussing risks of infertility or FP

Standardized patients and mechanical simulators in teaching and assessment at colleges of osteopathic medicine.

CONTEXT: A 2001 survey of 19 colleges of osteopathic medicine (COMs) revealed that standardized patient programs (SPPs) are increasingly used in osteopathic medical education. However, no new data have been published since. OBJECTIVES: To evaluate current SPP and mechanical simulator use at COMs compared with previous survey results. METHODS: In 2005, an electronic survey regarding the use of SPPs (eg, staffing, facilities) and mechanical simulators in the teaching and assessment of students' clinical skills was sent to the deans of the 23 fully accredited COMs and branch campuses. RESULTS: Responses were received from all 23 COMs for a 100% response rate. According to survey results, 19 COMs (87%) had active SPPs, 2 COMs (9%) reported that SPPs were in development, and the remaining 2 COMs (9%) used students as patients. In comparison, only 12 COMs (63%) in 2001 had active SPPs. Results indicated an increased use of standardized patients for assessment, particularly in physician-patient communication, osteopathic manipulative medicine, and osteopathic manipulative treatment. In addition, 12 COMs (52%) reported using mechanical simulators in the teaching or assessment of clinical skills. CONCLUSION: From 2001 to 2005, the use of SPPs and mechanical simulators at COMs increased substantially.

Discussion of fertility preservation with newly diagnosed patients: oncologists' views.

INTRODUCTION: Although physician discussion with patients regarding fertility preservation (FP) options prior to cancer treatment can provide important information for survivors concerning their future fertility, little is known about the extent to which physicians discuss FP with patients. This qualitative study sought to identify current physician FP communication practices and determine factors that may impact communication efforts regarding FP. MATERIALS AND METHODS: Qualitative data were collected using semi structured interviews with 16 physicians practicing at a major cancer center in the South. RESULTS: All providers were board certified in medical oncology, radiation oncology or surgical oncology. The main factors that emerged from qualitative analysis included distinct variations in quality of discussion about FP, knowledge of FP resources, attitudes, practice behaviors and perceptions of patient characteristics. DISCUSSION: While most physicians discussed potential fertility loss as a side effect of cancer treatment, few provided information to patients about preserving fertility. Patient characteristics such as gender and cancer site may impact the discussion, as well as system factors such as costs of procedures and access to FP resources. Education and training for physicians about FP options for cancer patients, particularly females, may promote discussion of FP. In addition, system barriers related to availability and affordability of FP resources must also be addressed. IMPLICATIONS FOR CANCER SURVIVORS: Physicians should consider providing patients with timely, understandable information related to their FP options, prior to the administration of treatment. Such discussions may lead to improved quality of life for individuals as they transition from patients to survivors.

Psychosocial and behavioral impact of genetic counseling and testing.

Over a decade has passed since the clinical availability of BRCA1/2 mutation testing for Hereditary Breast and Ovarian Cancer (HBOC). The purpose of this article is to review key areas of psychosocial and behavioral research related to genetic counseling and testing for BRCA1/2 mutations. Special attention will be given to understudied issues within each of these key areas. Where appropriate, the article will also highlight the clinical and research experiences of the authors. The first area that will be reviewed is the impact of genetic testing on psychological well-being. This will be followed by a brief discussion of a practical assessment strategy for psychosocial distress in clinical settings. Next, published data on the uptake of risk management options based on genetic testing results as well as the psychosocial impact of these behaviors will be reviewed. Thirdly, research focused on understanding the decision making at various points in the genetic counseling and testing process will also be examined. Finally, the available research on genetic counseling and testing in minority communities will be presented. By recognizing and addressing the psychosocial and behavioral issues faced by patients undergoing BRCA1/2 genetic counseling and testing, researchers and providers have the potential to maximize opportunities for prevention, early detection, and healthy coping.