ELF5 modulates the estrogen receptor cistrome in breast cancer.

Acquired resistance to endocrine therapy is responsible for half of the therapeutic failures in the treatment of breast cancer. Recent findings have implicated increased expression of the ETS transcription factor ELF5 as a potential modulator of estrogen action and driver of endocrine resistance, and here we provide the first insight into the mechanisms by which ELF5 modulates estrogen sensitivity. Using chromatin immunoprecipitation sequencing we found that ELF5 binding overlapped with FOXA1 and ER at super enhancers, enhancers and promoters, and when elevated, caused FOXA1 and ER to bind to new regions of the genome, in a pattern that replicated the alterations to the ER/FOXA1 cistrome caused by the acquisition of resistance to endocrine therapy. RNA sequencing demonstrated that these changes altered estrogen-driven patterns of gene expression, the expression of ER transcription-complex members, and 6 genes known to be involved in driving the acquisition of endocrine resistance. Using rapid immunoprecipitation mass spectrometry of endogenous proteins, and proximity ligation assays, we found that ELF5 interacted physically with members of the ER transcription complex, such as DNA-PKcs. We found 2 cases of endocrine-resistant brain metastases where ELF5 levels were greatly increased and ELF5 patterns of gene expression were enriched, compared to the matched primary tumour. Thus ELF5 alters ER-driven gene expression by modulating the ER/FOXA1 cistrome, by interacting with it, and by modulating the expression of members of the ER transcriptional complex, providing multiple mechanisms by which ELF5 can drive endocrine resistance

ELF5 suppresses estrogen sensitivity and underpins the acquisition of antiestrogen resistance in luminal breast cancer.

We have previously shown that during pregnancy the E-twenty-six (ETS) transcription factor ELF5 directs the differentiation of mammary progenitor cells toward the estrogen receptor (ER)-negative and milk producing cell lineage, raising the possibility that ELF5 may suppress the estrogen sensitivity of breast cancers. To test this we constructed inducible models of ELF5 expression in ER positive luminal breast cancer cells and interrogated them using transcript profiling and chromatin immunoprecipitation of DNA followed by DNA sequencing (ChIP-Seq). ELF5 suppressed ER and FOXA1 expression and broadly suppressed ER-driven patterns of gene expression including sets of genes distinguishing the luminal molecular subtype. Direct transcriptional targets of ELF5, which included FOXA1, EGFR, and MYC, accurately classified a large cohort of breast cancers into their intrinsic molecular subtypes, predicted ER status with high precision, and defined groups with differential prognosis. Knockdown of ELF5 in basal breast cancer cell lines suppressed basal patterns of gene expression and produced a shift in molecular subtype toward the claudin-low and normal-like groups. Luminal breast cancer cells that acquired resistance to the antiestrogen Tamoxifen showed greatly elevated levels of ELF5 and its transcriptional signature, and became dependent on ELF5 for proliferation, compared to the parental cells. Thus ELF5 provides a key transcriptional determinant of breast cancer molecular subtype by suppression of estrogen sensitivity in luminal breast cancer cells and promotion of basal characteristics in basal breast cancer cells, an action that may be utilised to acquire antiestrogen resistance

ELF5 drives lung metastasis in luminal breast cancer through recruitment of Gr1+ CD11b+ myeloid-derived suppressor cells

During pregnancy, the ETS transcription factor ELF5 establishes the milk-secreting alveolar cell lineage by driving a cell fate decision of the mammary luminal progenitor cell. In breast cancer, ELF5 is a key transcriptional determinant of tumor subtype and has been implicated in the development of insensitivity to anti-estrogen therapy. In the mouse mammary tumor virus-Polyoma Middle T (MMTV-PyMT) model of luminal breast cancer, induction of ELF5 levels increased leukocyte infiltration, angiogenesis, and blood vessel permeability in primary tumors and greatly increased the size and number of lung metastasis. Myeloid-derived suppressor cells, a group of immature neutrophils recently identified as mediators of vasculogenesis and metastasis, were recruited to the tumor in response to ELF5. Depletion of these cells using specific Ly6G antibodies prevented ELF5 from driving vasculogenesis and metastasis. Expression signatures in luminal A breast cancers indicated that increased myeloid cell invasion and inflammation were correlated with ELF5 expression, and increased ELF5 immunohistochemical staining predicted much shorter metastasis–free and overall survival of luminal A patients, defining a group who experienced unexpectedly early disease progression. Thus, in the MMTV-PyMT mouse mammary model, increased ELF5 levels drive metastasis by co-opting the innate immune system. As ELF5 has been previously implicated in the development of antiestrogen resistance, this finding implicates ELF5 as a defining factor in the acquisition of the key aspects of the lethal phenotype in luminal A breast cancer

Malodorous fungating wounds: Uncertain concepts underlying the management of social isolation

Malodorous fungating wounds can exacerbate the social isolation of patients with palliative care needs through changes in patients' body image. There is a lack of consensus regarding the most effective management approaches for patients with malodorous fungating wounds. This appears to relate to the existence of different theoretical frameworks for understanding altered body image. This article explores the theories used to create frameworks that have been used for interventions with patients experiencing social isolation arising from altered body image. It argues that there is a need for health care professionals to appreciate the lack of consensus within the literature and to understand this in the context of the relationship between theory and research. The author offers research and clinical recommendations

Malignant fungating wounds: An analysis of the lived experience

AIM: This paper reports upon a study that aimed to illuminate the meaning and experience of living with a malignant fungating wound. BACKGROUND: The current understanding of living with a malignant fungating wound is derived from professionals' rather than the patient's perspective. An appreciation of the lived experience may assist in the development of more empathetic support approaches. METHOD: A Heideggerian hermeneutic phenomenological approach was used as the philosophical framework. Unstructured interviews were conducted with a purposive sample of five participants. Content hermeneutic analysis was adopted to analyse the data. FINDINGS: Four themes were identified: representing the worst part of the patient's cancer; living within a body that cannot be trusted; a changing relationship with the patient's family and friends; and a loss of identity while continuously striving to be normal, yet feeling different. CONCLUSION: Health care professionals must possess a heightened awareness of: the importance of the impact of the wound upon day-to-day living, identity and purpose; the value of adopting the phrase used by the patient to describe their wound; and to focus more upon the subjective meaning of a visibly changing wound rather than objective measurement

Opioid prescribing in palliative care

Hundreds of thousands of people in the UK live with long-term or incurable illnesses for which strong opioids may be the only effective method of pain relief yet these drugs remain underused

Pain control in palliative care

Pain is one of the most feared symptoms of advanced, progressive disease and dying. It is a common but not universal experience in both advanced malignant and non-malignant conditions. A patient-centred approach involving systematic and thorough assessment, management and regular review can provide pain relief for most people. Even in advanced disease, it is important to identify the underlying cause of the pain. Pharmacological management should be structured around the analgesic ladder. Particular emphasis is given to the safe and effective use of strong opioids, including the person's information needs and the management of unwanted effects. A range of adjuvant drugs is also available, as are interventional techniques and non-pharmacological interventions. Guidance is provided on the reassessment of pain that has not responded adequately to the usual measures, and on indications for specialist referral

The role of the designated prescribing supervisor: An evaluation

Aim To understand the experience of non-medical prescribers undertaking the role of designated prescribing supervisor with students on the non-medical prescribing course for the first time. Methods Questionnaire completed by 34 designated prescribing supervisors, followed by semi-structured interviews with 10 designated prescribing supervisors. Findings There were four themes identified from the data. These were: knowledge and experience prior to undertaking the designated prescribing supervisor role; how the role of designated prescribing supervisor was enacted in practice; interactions and engagements necessary to support the designated prescribing supervisor and underpin students' professional development; and the way in which the designated prescribing supervisor role supports personal growth. Conclusion Designated prescribing supervisors in this evaluation described their role as consisting of coaching, advice and pastoral support. The supervision which they provided tended to be unscheduled and informal. Designated prescribing supervisors valued the support they received from the University and their Employer. Undertaking the role of designated prescribing supervisors was described as beneficial to their continuing professional development, it enhanced job satisfaction and provided a greater sense of self-worth

Mechanisms of action of ELF5 in breast cancer

The ETS transcription factor ELF5 is a critical regulator of cell fate. In the mammary epithelium, ELF5 drives the development of the ER-negative milk-producing alveolar cells, and the balance between ER and ELF5 transcriptional activity is hypothesised to be a fundamental determinant of cell fate. ELF5-driven transcriptional programs may also function in breast cancer, with previous studies demonstrating roles in basal-like and endocrine-resistant disease. The aim of this thesis was to investigate the transcriptional functions of ELF5 in breast cancer, and the factors that regulate ELF5 activity. A potential mechanism of ELF5 regulation is through alternative splicing, producing unique protein isoforms. There are four ELF5 isoforms; however little is known about their specific functions. ELF5 expression was comprehensively analysed at the isoform level, using RNA-sequencing data from 6,757 Cancer Genome Atlas samples. In breast cancer, ELF5 alterations were subtype-specific, with the basal subtype demonstrating unique isoform expression changes. Despite differences in protein domains, the in vitro functional effects of ELF5 isoforms were similar. Genome-wide sequencing studies were also performed to investigate ELF5 DNA binding sites and transcriptional effects in ER-positive breast cancer cells. ELF5 regulated transcriptional signatures of long-term oestrogen deprivation, suppression of the interferon response, and MYC-regulated gene expression. Increased ELF5 also redistributed the genomic binding sites of the ER pioneer factor FOXA1, representing a novel mechanism by which ELF5 may modulate the oestrogen response.Finally, interactions with other proteins are essential for specific transcriptional regulation. However, no ELF5-interacting proteins have previously been identified in human breast cancer cells. The protein interactions of chromatin-bound ELF5 were investigated using RIME, identifying DNA-PKcs. A transcriptional model involving ELF5, ER and DNA-PKcs was proposed, with important potential implications for the use of DNA-PKcs inhibitors in breast cancer treatment. Effective therapeutic targeting of transcription factors depends on a detailed understanding of how transcription factors function, the mechanisms that regulate them, and how these processes are dysregulated in cancer. The new insights into ELF5 function provided by this thesis represent an important contribution towards realising the potential of ELF5 as a therapeutic target in cancer