Apoptosis-modulatory miR-361-3p as a novel treatment target in endocrine-responsive and endocrine-resistant breast cancer.

Breast cancer (BC) is the most diagnosed cancer in women worldwide. In estrogen receptor (ER)-positive disease, anti-estrogens and aromatase inhibitors (AI) improve patient survival; however, many patients develop resistance. Dysregulation of apoptosis is a common resistance mechanism; thus, agents that can reinstate the activity of apoptotic pathways represent promising therapeutics for advanced drug-resistant disease. Emerging targets in this scenario include microRNAs (miRs). To identify miRs modulating apoptosis in drug-responsive and -resistant BC, a high-throughput miR inhibitor screen was performed, followed by high-content screening microscopy for apoptotic markers. Validation demonstrated that miR-361-3p inhibitor significantly increases early apoptosis and reduces proliferation of drug-responsive (MCF7), plus AI-/antiestrogen-resistant derivatives (LTED, TamR, FulvR), and ER- cells (MDA-MB-231). Importantly, proliferation-inhibitory effects were observed in vivo in a xenograft model, indicating the potential clinical application of miR-361-3p inhibition. RNA-seq of tumour xenografts identified FANCA as a direct miR-361-3p target, and validation suggested miR-361-3p inhibitor effects might be mediated in part through FANCA modulation. Moreover, miR-361-3p inhibition resulted in p53-mediated G1 cell cycle arrest through activation of p21 and reduced BC invasion. Analysis of publicly available datasets showed miR-361-3p expression is significantly higher in primary breast tumours vspaired normal tissue and is associated with decreased overall survival. In addition, miR-361-3p inhibitor treatment of BC patient explants decreased levels of miR-361-3p and proliferation marker, Ki67. Finally, miR-361-3p inhibitor showed synergistic effects on BC growth when combined with PARP inhibitor, Olaparib. Together, these studies identify miR-361-3p inhibitor as a potential new treatment for drug-responsive and -resistant advanced BC.

A non-coding RNA balancing act: miR-346-induced DNA damage is limited by the long non-coding RNA NORAD in prostate cancer.

BACKGROUND: miR-346 was identified as an activator of Androgen Receptor (AR) signalling that associates with DNA damage response (DDR)-linked transcripts in prostate cancer (PC). We sought to delineate the impact of miR-346 on DNA damage, and its potential as a therapeutic agent. METHODS: RNA-IP, RNA-seq, RNA-ISH, DNA fibre assays, in vivo xenograft studies and bioinformatics approaches were used alongside a novel method for amplification-free, single nucleotide-resolution genome-wide mapping of DNA breaks (INDUCE-seq). RESULTS: miR-346 induces rapid and extensive DNA damage in PC cells - the first report of microRNA-induced DNA damage. Mechanistically, this is achieved through transcriptional hyperactivation, R-loop formation and replication stress, leading to checkpoint activation and cell cycle arrest. miR-346 also interacts with genome-protective lncRNA NORAD to disrupt its interaction with PUM2, leading to PUM2 stabilisation and its increased turnover of DNA damage response (DDR) transcripts. Confirming clinical relevance, NORAD expression and activity strongly correlate with poor PC clinical outcomes and increased DDR in biopsy RNA-seq studies. In contrast, miR-346 is associated with improved PC survival. INDUCE-seq reveals that miR-346-induced DSBs occur preferentially at binding sites of the most highly-transcriptionally active transcription factors in PC cells, including c-Myc, FOXA1, HOXB13, NKX3.1, and importantly, AR, resulting in target transcript downregulation. Further, RNA-seq reveals widespread miR-346 and shNORAD dysregulation of DNA damage, replication and cell cycle processes. NORAD drives target-directed miR decay (TDMD) of miR-346 as a novel genome protection mechanism: NORAD silencing increases mature miR-346 levels by several thousand-fold, and WT but not TDMD-mutant NORAD rescues miR-346-induced DNA damage. Importantly, miR-346 sensitises PC cells to DNA-damaging drugs including PARP inhibitor and chemotherapy, and induces tumour regression as a monotherapy in vivo, indicating that targeting miR-346:NORAD balance is a valid therapeutic strategy. CONCLUSIONS: A balancing act between miR-346 and NORAD regulates DNA damage and repair in PC. miR-346 may be particularly effective as a therapeutic in the context of decreased NORAD observed in advanced PC, and in transcriptionally-hyperactive cancer cells.

The antiandrogen enzalutamide downregulates TMPRSS2 and reduces cellular entry of SARS-CoV-2 in human lung cells.

SARS-CoV-2 attacks various organs, most destructively the lung, and cellular entry requires two host cell surface proteins: ACE2 and TMPRSS2. Downregulation of one or both of these is thus a potential therapeutic approach for COVID-19. TMPRSS2 is a known target of the androgen receptor, a ligand-activated transcription factor; androgen receptor activation increases TMPRSS2 levels in various tissues, most notably prostate. We show here that treatment with the antiandrogen enzalutamide-a well-tolerated drug widely used in advanced prostate cancer-reduces TMPRSS2 levels in human lung cells and in mouse lung. Importantly, antiandrogens significantly reduced SARS-CoV-2 entry and infection in lung cells. In support of this experimental data, analysis of existing datasets shows striking co-expression of AR and TMPRSS2, including in specific lung cell types targeted by SARS-CoV-2. Together, the data presented provides strong evidence to support clinical trials to assess the efficacy of antiandrogens as a treatment option for COVID-19.

Did you see what I saw?: Comparing attentional synchrony during 360° video viewing in head mounted display and tablets.

Advances in head mounted displays (HMDs) have increased the interest in cinematic virtual reality as an art form. However, the freedom of a viewer in 360 video presents challenges in ensuring that audiences do not inadvertently miss important events and locations. We examined whether the high level of immersion provided by HMDs encourages participants to synchronize their attention during viewing. Sixty-four participants watched the 360° documentary Clouds Over Sidra (VRSE.works, 2015) using either an HMD or via a flat screen tablet display. We used intersubject correlation (ISC) analysis to measure attentional synchrony over the course of the video and to examine whether spatial and temporal factors led to different amounts of correlation both within and between groups. We found significantly greater ISC for the HMD compared to the tablet group. This effect was greatest for scenes with a unidirectional focus and at the start of scenes. We discuss our results in terms of the visual properties and the motor affordances of HMDs versus tablets. Our results show the value of HMDs in increasing attentional synchrony and may provide producers of 360° content insight in how to encourage or discourage synchronization of viewing direction. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

High fat diet causes distinct aberrations in the testicular proteome.

Diet has important effects on normal physiology and the potential deleterious effects of high fat diets and obesity on male reproductive health are being increasingly described. We conducted a histological review of the effects of chronic high fat (HF) diet (using a mouse model fed a 45% fat diet for 21 weeks) with a discovery proteomic study to assess for changes in the abundance of proteins in the testis. Mice on a HF diet became obese and developed glucose intolerance. Using mass spectrometry, we identify 102 proteins affected in the testis of obese mice. These included structural proteins important for the blood testis barrier (filamin A, FLNA), proteins involved in oxidative stress responses (spermatogenesis associated 20, SPATA-20) and lipid homoeostasis (sterol regulatory element-binding protein 2, SREBP2 and apolipoprotein A1, APOA1). In addition, an important regulator protein paraspeckle component 1, PSPC-1, which interacts with the androgen receptor was significantly downregulated. Proteomic data was validated using both Western blotting and immunostaining which confirmed and localised protein expression in both mouse and human testis using biopsy specimens. This study focused mainly on the abnormalities that occurred at the protein level and as a result, we have identified several candidate proteins and conducted pathway analysis around the effects of HF diet on the testis providing novel insights not previously described. Some of the identified targets could be targeted therapeutically and future work is directed in this area.

Intrapartum-related perinatal deaths in births planned in midwifery-led settings in Great Britain: findings and recommendations from the ESMiE confidential enquiry.

OBJECTIVE: To review quality of care in births planned in midwifery-led settings, resulting in an intrapartum-related perinatal death. DESIGN: Confidential enquiry. SETTING: England, Scotland and Wales. SAMPLE: Intrapartum stillbirths and intrapartum-related neonatal deaths in births planned in alongside midwifery units, freestanding midwifery units or at home, sampled from national perinatal surveillance data for 2015/16 (alongside midwifery units) and 2013-16 (freestanding midwifery units and home births). METHODS: Multidisciplinary panels reviewed medical notes for each death, assessing and grading quality of care by consensus, with reference to national standards and guidance. Data were analysed using thematic analysis and descriptive statistics. RESULTS: Sixty-four deaths were reviewed, 30 stillbirths and 34 neonatal deaths. At the start of labour care, 23 women were planning birth in an alongside midwifery unit, 26 in a freestanding midwifery unit and 15 at home. In 75% of deaths, improvements in care were identified that may have made a difference to the outcome for the baby. Improvements in care were identified that may have made a difference to the mother's physical and psychological health and wellbeing in 75% of deaths. Issues with care were identified around risk assessment and decisions about planning place of birth, intermittent auscultation, transfer during labour, resuscitation and neonatal transfer, follow up and local review. CONCLUSIONS: These confidential enquiry findings do not address the overall safety of midwifery-led settings for healthy women with straightforward pregnancies, but suggest areas where the safety of care can be improved. Maternity services should review their care with respect to our recommendations. TWEETABLE ABSTRACT: Confidential enquiry of intrapartum-related baby deaths highlights areas where care in midwifery-led settings can be made even safer.

Parents' experiences of care following the loss of a baby at the margins between miscarriage, stillbirth and neonatal death: a UK qualitative study.

OBJECTIVE: To explore the healthcare experiences of parents whose baby died either before, during or shortly after birth between 20+0 and 23+6  weeks of gestation in order to identify practical ways to improve healthcare provision. DESIGN: Qualitative interview study. SETTING: England through two parent support organisations and four NHS Trusts. SAMPLE: A purposive sample of parents. METHODS: Thematic analysis of semi-structured in-depth narrative interviews. MAIN OUTCOME MEASURES: Parents' healthcare experiences. RESULTS: The key overarching theme to emerge from interviews with 38 parents was the importance of the terminology used to refer to the death of their baby. Parents who were told they were 'losing a baby' rather than 'having a miscarriage' were more prepared for the realities of labour, the birth experience and for making decisions around seeing and holding their baby. Appropriate terminology validated their loss, and impacted on parents' health and wellbeing immediately following bereavement and in the longer term. CONCLUSION: For parents experiencing the death of their baby at the margins between miscarriage, stillbirth and neonatal death, ensuring the use of appropriate terminology that reflects parents' preferences is vital. This helps to validate their loss and prepare them for the experiences of labour and birth. Reflecting parents' language preferences combined with compassionate bereavement care is likely to have a positive impact on parents' experiences and improve longer-term outcomes. TWEETABLE ABSTRACT: Describing baby loss shortly before 24 weeks of gestation as a 'miscarriage' does not prepare parents for labour and birth, seeing their baby and making memories.

Availability of less invasive prenatal, perinatal and paediatric autopsy will improve uptake rates: a mixed-methods study with bereaved parents.

OBJECTIVE: To investigate whether less invasive methods of autopsy would be acceptable to bereaved parents and likely to increase uptake. DESIGN: Mixed methods study. SETTING: Bereaved parents recruited prospectively across seven hospitals in England and retrospectively through four parent support organisations. SAMPLE: Eight hundred and fifty-nine surveys and 20 interviews with bereaved parents. METHODS: Cross-sectional survey and qualitative semi-structured telephone interviews. MAIN OUTCOME MEASURES: Likely uptake, preferences, factors impacting decision-making, views on different autopsy methods. RESULTS: Overall, 90.5% of participants indicated that they would consent to some form of less invasive autopsy [either minimally invasive autopsy (MIA), non-invasive autopsy (NIA) or both]; 53.8% would consent to standard autopsy, 74.3% to MIA and 77.3% to NIA. Regarding parental preferences, 45.5% preferred MIA, 30.8% preferred NIA and 14.3% preferred standard autopsy. Participants who indicated they would decline standard autopsy but would consent to a less invasive option were significantly more likely to have a lower educational level (odds ratio 0.49; 95% CI 0.35-0.70; P = 0.000062). Qualitative findings suggest that parents value NIA because of the lack of any incision and MIA is considered a good compromise as it enables tissue sampling while easing the parental burden associated with consenting to standard autopsy. CONCLUSION: Less invasive methods of autopsy are acceptable alternatives for bereaved parents, and if offered, are likely to increase uptake and improve parental experience. Further health economic, validation and implementation studies are now required to assess the viability of offering these in routine widespread clinical care. TWEETABLE ABSTRACT: Mixed methods UK study finds less invasive methods of autopsy are acceptable alternatives for bereaved parents, and if offered, are likely to increase uptake and improve parental experience.

The prohibitin-repressive interaction with E2F1 is rapidly inhibited by androgen signalling in prostate cancer cells.

Prohibitin (PHB) is a tumour suppressor molecule with pleiotropic activities across several cellular compartments including mitochondria, cell membrane and the nucleus. PHB and the steroid-activated androgen receptor (AR) have an interplay where AR downregulates PHB, and PHB represses AR. Additionally, their cellular locations and chromatin interactions are in dynamic opposition. We investigated the mechanisms of cell cycle inhibition by PHB and how this is modulated by AR in prostate cancer. Using a prostate cancer cell line overexpressing PHB, we analysed the gene expression changes associated with PHB-mediated cell cycle arrest. Over 1000 gene expression changes were found to be significant and gene ontology analysis confirmed PHB-mediated repression of genes essential for DNA replication and synthesis, for example, MCMs and TK1, via an E2F1 regulated pathway-agreeing with its G1/S cell cycle arrest activity. PHB is known to inhibit E2F1-mediated transcription, and the PHB:E2F1 interaction was seen in LNCaP nuclear extracts, which was then reduced by androgen treatment. Upon two-dimensional western blot analysis, the PHB protein itself showed androgen-mediated charge differentiation (only in AR-positive cells), indicating a potential dephosphorylation event. Kinexus phosphoprotein array analysis indicated that Src kinase was the main interacting intracellular signalling hub in androgen-treated LNCaP cells, and that Src inhibition could reduce this AR-mediated charge differentiation. PHB charge change may be associated with rapid dissociation from chromatin and E2F1, allowing the cell cycle to proceed. The AR and androgens may deactivate the repressive functions of PHB upon E2F1 leading to cell cycle progression, and indicates a role for AR in DNA replication licensing.

Continuous daily assessment of multiple sclerosis disability using remote step count monitoring.

Disability measures in multiple sclerosis (MS) rely heavily on ambulatory function, and current metrics fail to capture potentially important variability in walking behavior. We sought to determine whether remote step count monitoring using a consumer-friendly accelerometer (Fitbit Flex) can enhance MS disability assessment. 99 adults with relapsing or progressive MS able to walk ≥2-min were prospectively recruited. At 4 weeks, study retention was 97% and median Fitbit use was 97% of days. Substudy validation resulted in high interclass correlations between Fitbit, ActiGraph and manual step count tally during a 2-minute walk test, and between Fitbit and ActiGraph (ICC = 0.76) during 7-day home monitoring. Over 4 weeks of continuous monitoring, daily steps were lower in progressive versus relapsing MS (mean difference 2546 steps, p < 0.01). Lower average daily step count was associated with greater disability on the Expanded Disability Status Scale (EDSS) (p < 0.001). Within each EDSS category, substantial variability in step count was apparent (i.e., EDSS = 6.0 range 1097-7152). Step count demonstrated moderate-strong correlations with other walking measures. Lower average daily step count is associated with greater MS disability and captures important variability in real-world walking activity otherwise masked by standard disability scales, including the EDSS. These results support remote step count monitoring as an exploratory outcome in MS trials.

Experiences with maternal and perinatal death reviews in the UK--the MBRRACE-UK programme.

Established in 1952, the programme of surveillance and Confidential Enquiries into Maternal Deaths in the UK is the longest running such programme worldwide. Although more recently instituted, surveillance and confidential enquiries into perinatal deaths are also now well established nationally. Recent changes to funding and commissioning of the Enquiries have enabled both a reinvigoration of the processes and improvements to the methodology with an increased frequency of future reporting. Close engagement with stakeholders and a regulator requirement for doctors to participate have both supported the impetus for involvement of all professionals leading to greater potential for improved quality of care for women and babies.

Prostate cancer cell malignancy via modulation of HIF-1α pathway with isoflurane and propofol alone and in combination.

BACKGROUND: Surgery is considered to be the first line treatment for solid tumours. Recently, retrospective studies reported that general anaesthesia was associated with worse long-term cancer-free survival when compared with regional anaesthesia. This has important clinical implications; however, the mechanisms underlying those observations remain unclear. We aim to investigate the effect of anaesthetics isoflurane and propofol on prostate cancer malignancy. METHODS: Prostate cancer (PC3) cell line was exposed to commonly used anaesthetic isoflurane and propofol. Malignant potential was assessed through evaluation of expression level of hypoxia-inducible factor-1α (HIF-1α) and its downstream effectors, cell proliferation and migration as well as development of chemoresistance. RESULTS: We demonstrated that isoflurane, at a clinically relevant concentration induced upregulation of HIF-1α and its downstream effectors in PC3 cell line. Consequently, cancer cell characteristics associated with malignancy were enhanced, with an increase of proliferation and migration, as well as development of chemoresistance. Inhibition of HIF-1α neosynthesis through upper pathway blocking by a PI-3K-Akt inhibitor or HIF-1α siRNA abolished isoflurane-induced effects. In contrast, the intravenous anaesthetic propofol inhibited HIF-1α activation induced by hypoxia or CoCl2. Propofol also prevented isoflurane-induced HIF-1α activation, and partially reduced cancer cell malignant activities. CONCLUSIONS: Our findings suggest that modulation of HIF-1α activity by anaesthetics may affect cancer recurrence following surgery. If our data were to be extrapolated to the clinical setting, isoflurane but not propofol should be avoided for use in cancer surgery. Further work involving in vivo models and clinical trials is urgently needed to determine the optimal anaesthetic regimen for cancer patients.

Revising the role of the androgen receptor in breast cancer.

Breast cancer (BC) is traditionally viewed as an oestrogen-dependent disease in which the androgen receptor (AR) is inhibitory, counteracting the oncogenic activity of oestrogen receptor α (ERα (ESR1)). Most probably as a result of this crosstalk, the AR has prognostic value in ER-positive disease, with AR positivity reported to correlate with a better prognosis. Activation of the AR pathway has been previously used as a therapeutic strategy to treat BC, but its usage declined following the introduction of the anti-oestrogen tamoxifen. More recently, it has been demonstrated that a subset of triple-negative BCs (molecular apocrine) are dependent upon androgen signalling for growth and therapies that inhibit androgen signalling, currently used for the treatment of prostate cancer, e.g. the antiandrogen bicalutamide and the CYP17 inhibitor abiraterone acetate are undergoing clinical trials to investigate their efficacy in this BC subtype. This review summarises the current knowledge of AR activity in BC.

Narratives in research: story as 'showing' the eminently ordinary experience of ageing.

AIM: To offer a perspective when research narratives about how ageing is lived in everyday life are the primary data. METHODS: A literature search explored the garnering of narratives about everyday life in advanced age in qualitative research. Narrative examples from the authors' research, and supervised student research, are drawn on to illustrate the experiences of ageing when going about an ordinary day. RESULTS: Stories show the lived experience of ageing is both ordinary and complex. Notions revealed are: age as constructed, as assumed by others, as being engaged every day, and as living the day my way. CONCLUSION: Understanding what it means to be older is in part shaped by which stories are told, who tells the stories and what sense is made of them. In gerontology research, 'story telling' can be a potent means of knowing what it means to be 'older' and of being worthy to self and others.

The full spectrum of handlebar injuries in children: a decade of experience.

BACKGROUND: Traumatic paediatric handlebar injury (HBI) is known to occur with different vehicles, affect different body regions, and have substantial associated morbidity. However, previous handlebar injury research has focused on the specific combination of abdominal injury and bicycle riding. Our aim was to fully describe the epidemiology and resultant spectrum of injuries caused by a HBI. METHODS: Retrospective data analysis of all paediatric patients (<18 years) in a prospectively identified trauma registry over a 10-year period. Primary outcome was the HBI, its location and management. The effects of patient age, vehicle type, the impact region, and Injury Severity Score (ISS) were also evaluated. HBI patients were compared against a cohort injured while riding similar vehicles, but not having sustained a HBI. RESULTS: 1990 patients were admitted with a handlebar-equipped vehicle trauma; 236 (11.9%) having sustained a HBI. HBI patients were twice as likely to be aged between 6 and 14 years old compared with non-HBI patients (OR 2.2; 95% CI 1.5-3.2). 88.6% of the HBI patients sustained an isolated injury, and 45.3% had non-abdominal handlebar impact. There were no significant differences in median ISS (p=0.4) or need for operative intervention (OR 1.1; 95% CI 0.9-1.5) between HBI and non-HBI patients. HBI patients had a significantly longer LOS (1.8 days vs. 1.2 days; p=0.001), and more frequently required a major operation (OR 3.4; 95% CI 2.2-5.4). The majority of splenic, renal and hepatic injuries were managed conservatively. CONCLUSIONS: Although the majority of paediatric HBI is associated with both intra-abdominal injury and bicycle riding, it produces a spectrum of potentially serious injuries and patients are more likely to undergo major surgery. Therefore these patients should always be treated with a high degree of suspicion.

Circulating microRNAs as potential new biomarkers for prostate cancer.

Since they were first described in the 1990s, circulating microRNAs (miRNAs) have provided an active and rapidly evolving area of current research that has the potential to transform cancer diagnostics and therapeutics. In particular, miRNAs could provide potential new biomarkers for prostate cancer, the most common cause of cancer in UK men. Current diagnostic tests for prostate cancer have low specificity and poor sensitivity. Further, although many prostate cancers are so slow growing as not to pose a major risk to health, there is currently no test to distinguish between these and cancers that will become aggressive and life threatening. Circulating miRNAs are highly stable and are both detectable and quantifiable in a range of accessible bio fluids, thus have the potential to be useful diagnostic, prognostic and predictive biomarkers. This review aims to summarise the current understanding of circulating miRNAs in prostate cancer patients and their potential role as biomarkers.

Reducing prohibitin increases histone acetylation, and promotes androgen independence in prostate tumours by increasing androgen receptor activation by adrenal androgens.

Prostate cancers (PCs), initially responsive to anti-androgen therapies, often advance to a hormone-refractory 'castrate-resistant' PC (CRPC) stage. However, the androgen receptor (AR) pathway remains active and key for cell growth and gene expression within tumours, even in the apparent absence of hormone. Proposed mechanisms to explain progression, including AR amplification/mutation, are insufficient to completely explain CRPC and possible roles of AR cofactors such as prohibitin (PHB) are poorly understood. We investigated whether PHB loss could sensitise PC cells and tumours to adrenal gland-derived androgens, which persist even after androgen ablation, hence contribute to development of CRPC. Using a pair of PC cell lines, inducibly expressing ectopic cDNA or RNAi for PHB, responses to different androgens and hormone concentrations were studied both in vitro and in vivo. PHB was found at the promoters of several genes, both AR and non-AR-regulated, and knockdown increased histone acetylation at these promoters. Further, PHB knockdown increased the rate of AR ligand-induced chromatin binding, and binding rate and occupancy of AR upon the PSA promoter. This resulted in increased cell growth and AR activity in response to all androgens, including promoting a response to the weaker adrenal androgens previously absent at physiological concentrations. In vivo this had functional consequences such that PHB knockdown resulted in androstenedione being sufficient to promote tumour growth, under conditions mimicking those in patients undergoing androgen ablation therapy. We conclude that reduction in PHB levels is sufficient to lower the threshold of AR activity in vitro and in vivo; this may be via a general increase in histone acetylation that could potentially affect signalling by other transcription factors. PHB loss may provide a mechanism for progression to CRPC by sensitising PC cells to 'castrate' conditions-that is, low levels of testicular androgens in the continued presence of weak adrenal and dietary androgens.

HEY1 Leu94Met gene polymorphism dramatically modifies its biological functions.

The hairy/enhancer-of-split related with YRPW motif 1 (HEY1) is a member of the basic-helix-loop-helix-Orange (bHLH-O) family of transcriptional repressors that mediate Notch signaling. Several cancer-related pathways also regulate HEY1 expression, and HEY1 itself acts as an indirect positive regulator of the p53 tumor suppressor protein and a negative regulator of androgen receptor activity. In this study we show how a naturally occurring non-synonymous polymorphism at codon 94 of HEY1, which results in a substitution of leucine by methionine (Leu94Met), converts HEY1 from an androgen receptor corepressor to an androgen receptor co-activator without affecting its intrinsic transcriptional repressive domains. The polymorphism Leu94Met also abolishes HEY1-mediated activation of p53 and suppresses the ability of HEY1 to induce p53-dependent cell-cycle arrest and aberrant cell differentiation in human osteosarcoma U2OS cells. Moreover, expression of HEY1, but not of the variant Leu94Met, confers sensitivity to p53-activating chemotherapeutic drugs on U2OS cells. In addition, we have identified motifs in HEY1 that are critical for the regulation of its subcellular localization and analysed how mutations in those motifs affect both HEY1 and HEY1-Leu94Met functions. These findings suggest that the polymorphism Leu94Met in HEY1 radically alters its biological activities and may affect oncogenic processes.

The role of androgen receptor mutations in prostate cancer progression.

Prostate tumour growth is almost always dependent upon the androgen receptor pathway and hence therapies aimed at blocking this signalling axis are useful tools in the management of this disease. Unfortunately such therapies invariably fail; and the tumour progresses to an "androgen-independent" stage. In such cases androgen receptor expression is almost always maintained and much evidence exists to suggest that it may still be driving growth. One mechanism by which the receptor is thought to remain active is mutation. This review summarises the present data on androgen receptor mutations in prostate cancer, and how such substitutions offer a growth advantage by affecting cofactor interactions or by reducing ligand specificity. Such alterations appear to have a subsequent effect upon gene expression suggesting that tumours may "behave" differently dependent upon the ligand promoting growth and if a mutation is present.