1,722 research outputs found
Hsp90-binding immunophilins link p53 to dynein during p53 transport to the nucleus
The tumor suppressor protein p53 is known to be transported to the nucleus along microtubular tracks by cytoplasmic dynein. However, the connection between p53 and the dynein motor protein complex has not been established. Here, we show that hsp90.binding immunophilins link p53.hsp90 complexes to dynein and that prevention of that linkage in vivo inhibits the nuclear movement of p53. First, we show that p53.hsp90 heterocomplexes from DLD-1 human colon cancer cells contain an immunophilin (FKBP52, CyP-40, or PP5) as well as dynein. p53.hsp90.immunophilin.dynein complexes can be formed by incubating immunopurified p53 with rabbit reticulocyte lysate, and we show by peptide competition that the immunophilins link via their tetratricopeptide repeat domains to p53-bound hsp90 and by means of their PPIase domains to the dynein complex. The linkage of immunophilins to the dynein motor is indirect by means of the dynamitin component of the dynein-associated dynactin complex, and we show that purified FKBP52 binds directly by means of its PPIase domain to purified dynamitin. By using a temperature-sensitive mutant of p53 where cytoplasmic-nuclear movement occurs by shift to permissive temperature, we show that p53 movement is impeded when p53 binding to hsp90 is inhibited by the hsp90 inhibitor radicicol. Also, nuclear movement of p53 is inhibited when immunophilin binding to dynein is competed for by expression of a PPIase domain fragment in the same manner as when dynein linkage to cargo is dissociated by expression of dynamitin. This is the first demonstration of the linkage between an hsp90-chaperoned transcription factor and the system for its retrograde movement to the nucleus both in vitro and in vivo.Fil: Galigniana, Mario Daniel. University of Michigan; Estados Unidos. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Química Biológica; ArgentinaFil: Harrell, Jennifer M.. University of Michigan; Estados UnidosFil: O´Hagen, Heather M.. University of Michigan; Estados UnidosFil: Ljungman, Mats. University of Michigan; Estados UnidosFil: Pratt, William B.. University of Michigan; Estados Unido
Who is pirating medical literature? A bibliometric review of 28 million Sci-Hub downloads.
We aimed to define the proportion of downloads on Sci-Hub that are medical in nature and to consider these data at the national level, evaluating the relation between density of medical literature downloads and scientific output, national income classifications, and indicators of internet penetrance
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Sexual Dysfunction and Reproductive Concerns in Young Men Diagnosed With Testicular Cancer: An Observational Study
INTRODUCTION: The survival rates for testicular cancer are excellent; still, there is a lack of knowledge regarding important survivorship issues, such as sexual dysfunction and reproductive concerns. AIM: The aim of this study was to investigate the prevalence and predictors of sexual dysfunction and reproductive concerns and the potential association between these issues in young men ∼2 years after a diagnosis of testicular cancer. METHODS: Data were collected from 111 men (response rate = 50%) diagnosed with testicular cancer at age 16-39. Patients were identified via the Swedish National Quality Registry for Testicular Cancer and approached with a survey, including standardized measures of sexual function, reproductive concerns, body image, and health-related quality of life. The survey was sent to participants approximately 2 years after their cancer diagnosis. Clinical variables were collected from the registry. Predictors were identified by multivariable linear regression analyses. MAIN OUTCOME MEASURES: The main outcomes were sexual function, assessed with the Patient-Reported Outcomes Measurement Information System Sexual Function and Satisfaction measure version 2.0, and reproductive concerns, assessed with the Reproductive Concerns After Cancer scale. RESULTS: Sexual dysfunction was reported by 26% of men, and a high level of reproductive concerns was reported by 28%. Lower satisfaction with sex life was associated with older age (β = -0.41), negative body image (β = -0.42), not having a partner (β = 4.8), and dissatisfaction with sex life before cancer (β = 8.31). Negative body image was associated with reproductive concerns in the dimensions of fertility potential (β = 0.06), partner disclosure (β = 0.08), and child's health (β = 0.07), whereas having had fertility preservation predicted higher levels of concerns with regard to personal health (β = 0.52) and achieving pregnancy (β = 0.53). Clinical variables did not predict either sexual function or reproductive concerns. CLINICAL IMPLICATIONS: Our results show that the majority of young men diagnosed with testicular cancer do not report sexual dysfunction or reproductive concerns 2 years after diagnosis. A sizeable minority, however, does report dysfunction or reproductive concerns, which should be recognized in the follow-up care of this population. STRENGTHS & LIMITATIONS: A strength of the study is the use of high-quality registry data and validated instruments. The lack of Swedish norms for sexual function and reproductive concerns is a possible limitation. CONCLUSION: A subgroup of young men treated for testicular cancer report sexual dysfunction or reproductive concerns approximately 2 years after diagnosis. Factors associated with these issues seem to mainly be psychological, rather than medical, nature. Ljungman L, Eriksson LE, Flynn KE, et al. Sexual Dysfunction and Reproductive Concerns in Young Men Diagnosed With Testicular Cancer: An Observational Study. J Sex Med 2019;16:1049-1059
Mutant p53R270H drives altered metabolism and increased invasion in pancreatic ductal adenocarcinoma
Pancreatic cancer is characterized by nearly universal activating mutations in KRAS. Among other somatic mutations, TP53 is mutated in more than 75% of human pancreatic tumors. Genetically engineered mice have proven instrumental in studies of the contribution of individual genes to carcinogenesis. Oncogenic Kras mutations occur early during pancreatic carcinogenesis and are considered an initiating event. In contrast, mutations in p53 occur later during tumor progression. In our model, we recapitulated the order of mutations of the human disease, with p53 mutation following expression of oncogenic Kras. Further, using an inducible and reversible expression allele for mutant p53, we inactivated its expression at different stages of carcinogenesis. Notably, the function of mutant p53 changes at different stages of carcinogenesis. Our work establishes a requirement for mutant p53 for the formation and maintenance of pancreatic cancer precursor lesions. In tumors, mutant p53 becomes dispensable for growth. However, it maintains the altered metabolism that characterizes pancreatic cancer and mediates its malignant potential. Further, mutant p53 promotes epithelial-mesenchymal transition (EMT) and cancer cell invasion. This work generates new mouse models that mimic human pancreatic cancer and expands our understanding of the role of p53 mutation, common in the majority of human malignancies
Guided internet-administered self-help to reduce symptoms of anxiety and depression among adolescents and young adults diagnosed with cancer during adolescence (U-CARE: YoungCan): a study protocol for a feasibility trial.
Published onlineJournal ArticleThis is the final version of the article. Available from BMJ Publishing Group via the DOI in this record.INTRODUCTION: A subgroup of adolescents and young adults diagnosed with cancer during adolescence reports elevated levels of anxiety and depressive symptoms and unmet needs for psychological support. Evidence-based psychological treatments tailored for this population are lacking. This protocol describes a feasibility study of a guided-internet-administered self-help programme (YoungCan) primarily targeting symptoms of anxiety and depression among young persons diagnosed with cancer during adolescence and of the planned study procedures for a future controlled trial. METHODS/ANALYSIS: The study is an uncontrolled feasibility trial with a pre-post and 3-month follow-up design. Potential participants aged 15-25 years, diagnosed with cancer during adolescence, will be identified via the Swedish Childhood Cancer Registry. 30 participants will be included. Participants will receive YoungCan, a 12-week therapist-guided, internet-administered self-help programme consisting primarily of cognitive-behavioural therapy organised into individually assigned modules targeting depressive symptoms, worry and anxiety, body dissatisfaction and post-traumatic stress. Interactive peer support and psychoeducative functions are also available. Feasibility outcomes include: recruitment and eligibility criteria; data collection; attrition; resources needed to complete the study and programme; safety procedures; participants' and therapists' adherence to the programme; and participants' acceptability of the programme and study methodology. Additionally, mechanisms of impact will be explored and data regarding symptoms of anxiety, depression, post-traumatic stress, body dissatisfaction, reactions to social interactions, quality of life, axis I diagnoses according to the Mini International Neuropsychiatric Interview and healthcare service use will be collected. Exploratory analyses of changes in targeted outcomes will be conducted. ETHICS/DISSEMINATION: This feasibility protocol was approved by the Regional Ethical Review Board in Uppsala, Sweden (ref: 2016/210). Findings will be disseminated to relevant research, clinical, health service and patient communities through publications in peer-reviewed and popular science journals and presentations at scientific and clinical conferences. TRIAL REGISTRATION NUMBER: ISRCTN97835363.This work was supported by the Swedish Childhood Cancer Foundation, grant number PR2013-0039. This funding source had no role in the design of this study and will not have any role during its execution, analyses, interpretation of the data or decision to submit results
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Feasibility of a self-help web-based intervention targeting young cancer patients with sexual problems and fertility distress
PURPOSE: The purpose of the study is to evaluate the feasibility of a self-help web-based intervention to alleviate sexual problems and fertility distress in adolescents and young adults with cancer.
METHODS: Twenty-three persons with cancer (19 women and 4 men, age 18-43, 1-5 years post-diagnosis of lymphoma, breast, gynecologic, central nervous system, or testicular cancer) were recruited to test a 2-month web-based program targeting sexual problems or fertility distress. The programs were organized in modules with educational and behavior change content, including texts, illustrations, exercises, and video vignettes. The program also included a discussion forum and an "ask the expert" forum. In addition, the sexuality program offered two telephone consultations. Feasibility (regarding demand, acceptability, preliminary efficacy, and functionality) was evaluated with the website system data, telephone interviews, continuous online evaluations, and study-specific measures.
RESULTS: Fifteen participants completed four modules or more. Most of the program features were used and well accepted by these "committed users." The web-based format enabled flexible use by participants with diverse needs. Preliminary efficacy was indicated by self-reported increased knowledge and skill in handling sexual problems and fertility distress. The website was easy to use and functioned well technically.
CONCLUSIONS: The present study indicated that this web-based intervention was feasible for adolescents and young adults with cancer. The effectiveness of the intervention in decreasing sexual problems and fertility distress will be tested in a population-based randomized controlled trial for adolescents and young adults with cancer.
TRIAL REGISTRATION: ISRCTN36621459
Postexposure prophylaxis against varicella-zoster virus infection among recipients of hematopoietic stem cell transplant: Unresolved issues
Haematopoietic stem cell transplantation for patients with myelodysplastic syndromes and secondry acute myeloid leukaemias: A report on behalf of the Chronic Leukaemia Working Party of the European Group for Blood and Marrow Transplantation (EBMT)
UVSSA and USP7, a new couple in transcription-coupled DNA repair
Transcription-coupled nucleotide excision repair (TC-NER) specifically removes transcription-blocking lesions from our genome. Defects in this pathway are associated with two human disorders: Cockayne syndrome (CS) and UV-sensitive syndrome (UVSS). Despite a similar cellular defect in the UV DNA damage response, patients with these syndromes exhibit strikingly distinct symptoms; CS patients display severe developmental, neurological, and premature aging features, whereas the phenotype of UVSS patients is mostly restricted to UV hypersensitivity. The exact molecular mechanism behind these clinical differences is still unknown; however, they might be explained by additional functions of CS proteins beyond TC-NER. A short overview of the current hypotheses addressing possible molecular mechanisms and the proteins involved are presented in this review. In addition, we will focus on two new players involved in TC-NER which were recently identified: UV-stimulated scaffold protein A (UVSSA) and ubiquitin-specific protease 7 (USP7). UVSSA has been found to be the causative gene for UVSS and, together with USP7, is implicated in regulating TC-NER activity. We will discuss the function of UVSSA and USP7 and how the discovery of these proteins contributes to a better understanding of the molecular mechanisms underlying the clinical differences between UVSS and the more severe CS
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