The Function of Steroid Receptor Coactivator-1 in Normal Tissues and Cancer

In 1995, the steroid receptor coactivator-1 (SRC-1) was identified as the first authentic steroid receptor coactivator. Since then, the SRC proteins have remained at the epicenter of coregulator biology, molecular endocrinology and endocrine-related cancer. Cumulative works on SRC-1 have shown that it is primarily a nuclear receptor coregulator and functions to construct highly specific enzymatic protein complexes which can execute efficient and successful transcriptional activation of designated target genes. The versatile nature of SRC-1 enables it to respond to steroid dependent and steroid independent stimulation, allowing it to bind across many families of transcription factors to orchestrate and regulate complex physiological reactions. This review highlights the multiple functions of SRC-1 in the development and maintenance of normal tissue functions as well as its major role in mediating hormone receptor responsiveness. Insights from genetically manipulated mouse models and clinical data suggest SRC-1 is significantly overexpressed in many cancers, in particular, cancers of the reproductive tissues. SRC-1 has been associated with cellular proliferation and tumor growth but its major tumorigenic contributions are promotion and execution of breast cancer metastasis and mediation of resistance to endocrine therapies. The ability of SRC-1 to coordinate multiple signaling pathways makes it an important player in tumor cells' escape of targeted therapy

Prosaposin activates the androgen receptor and potentiates resistance to endocrine treatment in breast cancer.

INTRODUCTION: HOX genes play vital roles in growth and development, however, atypical redeployment of these genes is often associated with steroidal adaptability in endocrine cancers. We previously identified HOXC11 to be an indicator of poor response to hormonal therapy in breast cancer. In this study we aimed to elucidate genes regulated by HOXC11 in the endocrine resistant setting. METHODS: RNA-sequencing paired with transcription factor motif-mapping was utilised to identify putative HOXC11 target genes in endocrine resistant breast cancer. Validation and functional evaluation of the target gene, prosaposin (PSAP), was performed in a panel of endocrine sensitive and resistant breast cancer cell lines. The clinical significance of this finding was explored in clinical cohorts at both mRNA and protein level. RESULTS: PSAP was shown to be regulated by HOXC11 in both tamoxifen and aromatase inhibitor (AI) resistant cell lines. Transcript levels of HOXC11 and PSAP correlated strongly in samples of primary breast tumours (r = 0.7692, n = 51). PSAP has previously been reported to activate androgen receptor (AR) in prostate cancer cells. In a panel of breast cancer cell lines it was shown that endocrine resistant cells exhibit innately elevated levels of AR compared to their endocrine sensitive counterparts. Here, we demonstrate that stimulation with PSAP can drive AR recruitment to a hormone response element (HRE) in AI resistant breast cancer cells. Functionally, PSAP promotes cell migration and invasion only in AI resistant cells and not in their endocrine sensitive counterparts. In a cohort of breast cancer patients (n = 34), elevated serum levels of PSAP were found to associate significantly with poor response to endocrine treatment (p = 0.04). Meta-analysis of combined PSAP and AR mRNA are indicative of poor disease-free survival in endocrine treated breast cancer patients (hazard ratio (HR): 2.2, P = 0.0003, n = 661). CONCLUSION: The HOXC11 target gene, PSAP, is an AR activator which facilitates adaptation to a more invasive phenotype in vitro. These findings have particular relevance to the development of resistance to AI therapy which is an emerging clinical issue. PSAP is a secreted biomarker which has potential in identifying patients failing to exhibit sustained response to hormonal treatment

Between division and connection: a qualitative study of the impact of COVID-19 restrictions on social relationships in the United Kingdom.

Background: The first national COVID-19 lockdown in the United Kingdom between March to July 2020 resulted in sudden and unprecedented disruptions to daily life. This study sought to understand the impact of COVID-19 non-pharmaceutical interventions (NPIs), such as social distancing and quarantine, on people's lived experiences, focusing on social connections and relationships. Methods: Data were generated through 20 in-depth online and telephone interviews, conducted between May and July 2020, and analysed using thematic analysis informed by an ecological framework. Results: Findings show that the use of NPIs impacted social relationships and sociality at every level, disrupting participant's sense of self; relationships with their partners, household members, neighbours, and communities; and polarising social and political views. However, experiences of personal meaning-making and reflection, and greater social connectedness, solidarity, and compassion - despite physical distance - were also common. Conclusions: Participant's lived experiences of the first UK lockdown underscore the interconnectedness of relationships at the individual, community and societal level and point towards the important role of trust, social cohesion, and connectedness in coping with pandemic stress and adversity. Where infectious disease prevention measures rupture sociality, support for social connection at every relational level is likely to help build resilience in light of ongoing COVID-19 restrictions

Enhanced ultrafast X-ray diffraction by transient resonances

Diffraction-before-destruction imaging with single ultrashort X-ray pulses has the potential to visualise non-equilibrium processes, such as chemical reactions, at the nanoscale with sub-femtosecond resolution in the native environment without the need of crystallization. Here, a nanospecimen partially diffracts a single X-ray flash before sample damage occurs. The structural information of the sample can be reconstructed from the coherent X-ray interference image. State-of-art spatial resolution of such snapshots from individual heavy element nanoparticles is limited to a few nanometers. Further improvement of spatial resolution requires higher image brightness which is ultimately limited by bleaching effects of the sample. We compared snapshots from individual 100 nm Xe nanoparticles as a function of the X-ray pulse duration and incoming X-ray intensity in the vicinity of the Xe M-shell resonance. Surprisingly, images recorded with few femtosecond and sub-femtosecond pulses are up to 10 times brighter than the static linear model predicts. Our Monte-Carlo simulation and statistical analysis of the entire data set confirms these findings and attributes the effect to transient resonances. Our simulation suggests that ultrafast form factor changes during the exposure can increase the brightness of X-ray images by several orders of magnitude. Our study guides the way towards imaging with unprecedented combination of spatial and temporal resolution at the nanoscale

ADAM22/LGI1 complex as a new actionable target for breast cancer brain metastasis

Background: Metastatic breast cancer is a major cause of cancer-related deaths in woman. Brain metastasis is a common and devastating site of relapse for several breast cancer molecular subtypes, including oestrogen receptor-positive disease, with life expectancy of less than a year. While efforts have been devoted to developing therapeutics for extra-cranial metastasis, drug penetration of blood–brain barrier (BBB) remains a major clinical challenge. Defining molecular alterations in breast cancer brain metastasis enables the identification of novel actionable targets.Methods: Global transcriptomic analysis of matched primary and metastatic patient tumours (n = 35 patients, 70 tumour samples) identified a putative new actionable target for advanced breast cancer which was further validated in vivo and in breast cancer patient tumour tissue (n = 843 patients). A peptide mimetic of the target's natural ligand was designed in silico and its efficacy assessed in in vitro, ex vivo and in vivo models of breast cancer metastasis.Results: Bioinformatic analysis of over-represented pathways in metastatic breast cancer identified ADAM22 as a top ranked member of the ECM-related druggable genome specific to brain metastases. ADAM22 was validated as an actionable target in in vitro, ex vivo and in patient tumour tissue (n = 843 patients). A peptide mimetic of the ADAM22 ligand LGI1, LGI1MIM, was designed in silico. The efficacy of LGI1MIM and its ability to penetrate the BBB were assessed in vitro, ex vivo and in brain metastasis BBB 3D biometric biohybrid models, respectively. Treatment with LGI1MIM in vivo inhibited disease progression, in particular the development of brain metastasis.Conclusion: ADAM22 expression in advanced breast cancer supports development of breast cancer brain metastasis. Targeting ADAM22 with a peptide mimetic LGI1MIM represents a new therapeutic option to treat metastatic brain disease

Is the Nintendo Wii Fit really acceptable to older people?: a discrete choice experiment

<p>Abstract</p> <p>Background</p> <p>Interactive video games such as the Nintendo Wii Fit are increasingly used as a therapeutic tool in health and aged care settings however, their acceptability to older people is unclear. The aim of this study was to determine the acceptability of the Nintendo Wii Fit as a therapy tool for hospitalised older people using a discrete choice experiment (DCE) before and after exposure to the intervention.</p> <p>Methods</p> <p>A DCE was administered to 21 participants in an interview style format prior to, and following several sessions of using the Wii Fit in physiotherapy. The physiotherapist prescribed the Wii Fit activities, supervised and supported the patient during the therapy sessions. Attributes included in the DCE were: mode of therapy (traditional or using the Wii Fit), amount of therapy, cost of therapy program and percentage of recovery made. Data was analysed using conditional (fixed-effects) logistic regression.</p> <p>Results</p> <p>Prior to commencing the therapy program participants were most concerned about therapy time (avoiding programs that were too intensive), and the amount of recovery they would make. Following the therapy program, participants were more concerned with the mode of therapy and preferred traditional therapy programs over programs using the Wii Fit.</p> <p>Conclusions</p> <p>The usefulness of the Wii Fit as a therapy tool with hospitalised older people is limited not only by the small proportion of older people who are able to use it, but by older people's preferences for traditional approaches to therapy. Mainstream media portrayals of the popularity of the Wii Fit with older people may not reflect the true acceptability in the older hospitalised population.</p

Supporting insulin initiation in type 2 diabetes in primary care: results of the Stepping Up pragmatic cluster randomised controlled clinical trial.

Objective To compare the effectiveness of a novel model of care ("Stepping Up") with usual primary care in normalising insulin initiation for type 2 diabetes, leading to improved glycated haemoglobin (HbA1c) levels.Design Cluster randomised controlled trial.Setting Primary care practices in Victoria, Australia, with a practice nurse and at least one consenting eligible patient (HbA1c ≥7.5% with maximal oral treatment).Participants 266 patients with type 2 diabetes and 74 practices (mean cluster size 4 (range 1-8) patients), followed up for 12 months.Intervention The Stepping Up model of care intervention involved theory based change in practice systems and reorientation of the roles of health professionals in the primary care diabetes team. The core components were an enhanced role for the practice nurse in leading insulin initiation and mentoring by a registered nurse with diabetes educator credentials.Main outcome measures The primary endpoint was change in HbA1c. Secondary endpoints included the proportion of participants who transitioned to insulin, proportion who achieved target HbA1c, and a change in depressive symptoms (patient health questionnaire, PHQ-9), diabetes specific distress (problem areas in diabetes scale, PAID), and generic health status (assessment of quality of life instrument, AQoL-8D).Results HbA1c improved in both arms, with a clinically significant between arm difference (mean difference -0.6%, 95% confidence interval -0.9% to -0.3%), favouring the intervention. At 12 months, in intervention practices, 105/151 (70%) of participants had started insulin, compared with 25/115 (22%) in control practices (odds ratio 8.3, 95% confidence interval 4.5 to 15.4, P<0.001). Target HbA1c (≤7% (53 mmol/mol)) was achieved by 54 (36%) intervention participants and 22 (19%) control participants (odds ratio 2.2, 1.2 to 4.3, P=0.02). Depressive symptoms did not worsen at 12 months (PHQ-9: -1.1 (3.5) v -0.1 (2.9), P=0.05). A statistically significant difference was found between arms in the mean change in mental health (AQoL mental component summary: 0.04 (SD 0.16) v -0.002 (0.13), mean difference 0.04 (95% confidence interval 0.002 to 0.08), P=0.04), favouring the intervention, but no significant difference in physical health (AQoL physical component summary: 0.03 (0.15) v 0.02 (0.13)) nor diabetes specific distress (5.6 (15.5) v -2.4 (15.4)). No severe hypoglycaemia events were reported.Conclusions The Stepping Up model of care was associated with increased insulin initiation rates in primary care, and improvements in glycated haemoglobin without worsening emotional wellbeing.Trial registration Australian and New Zealand Clinical Trials Registry ACTRN12612001028897

Network analysis of SRC-1 reveals a novel transcription factor hub which regulates endocrine resistant breast cancer.

Steroid receptor coactivator 1 (SRC-1) interacts with nuclear receptors and other transcription factors (TFs) to initiate transcriptional networks and regulate downstream genes which enable the cancer cell to evade therapy and metastasise. Here we took a top-down discovery approach to map out the SRC-1 transcriptional network in endocrine resistant breast cancer. First, rapid immunoprecipitation mass spectrometry of endogenous proteins (RIME) was employed to uncover new SRC-1 TF partners. Next, RNA sequencing (RNAseq) was undertaken to investigate SRC-1 TF target genes. Molecular and patient-derived xenograft studies confirmed STAT1 as a new SRC-1 TF partner, important in the regulation of a cadre of four SRC-1 transcription targets, NFIA, SMAD2, E2F7 and ASCL1. Extended network analysis identified a downstream 79 gene network, the clinical relevance of which was investigated in RNAseq studies from matched primary and local-recurrence tumours from endocrine resistant patients. We propose that SRC-1 can partner with STAT1 independently of the estrogen receptor to initiate a transcriptional cascade and control regulation of key endocrine resistant genes