Re-examining advice to complete antibiotic courses: a qualitative study with clinicians and patients

BACKGROUND: Antibiotic treatment duration may be longer than sometimes needed. Stopping antibiotics early, rather than completing pre-set antibiotic courses, may help reduce unnecessary exposure to antibiotics and antimicrobial resistance (AMR). AIM: To identify clinicians' and patients' views on stopping antibiotics when better (SAWB) for urinary tract infections (UTIs), and to explore comparisons with other acute infections. DESIGN & SETTING: An exploratory qualitative study with general practice clinicians and patients in England. METHOD: Primary care clinicians and patients who had recent UTI experience were recruited in England. Remote one-to-one interviews with clinicians and patients, and one focus group with patients, were conducted. Data were audiorecorded, transcribed, and analysed thematically. RESULTS: Eleven clinicians (seven GPs) and 19 patients (14 with experience of recurrent and/or chronic UTIs) were included. All participants considered SAWB unfamiliar and contradictory to well-known advice to complete antibiotic courses, but were interested in the evidence for risks and benefits of SAWB. Clinicians were amenable if evidence and guidelines supported it, whereas patients were more averse because of concerns about the risk of UTI recurrence and/or complications and AMR. Participants viewed SAWB as potentially more appropriate for longer antibiotic courses and other infections (with longer courses and lower risk of recurrence and/or complications). Participants stressed the need for unambiguous advice and SAWB as part of shared decision making and personalised advice. CONCLUSION: Patients were less accepting of SAWB, whereas clinicians were more amenable to it. Patients and clinicians require good evidence that this novel approach to self-determining antibiotic duration is safe and beneficial. If evidence based, SAWB should be offered with an explanation of why the advice differs from the ‘complete the course’ instruction, and a clear indication of when exactly to stop antibiotics should be given

Epidermal Growth Factor Cytoplasmic Domain Affects ErbB Protein Degradation by the Lysosomal and Ubiquitin-Proteasome Pathway in Human Cancer Cells12

The cytoplasmic domains of EGF-like ligands, including EGF cytoplasmic domain (EGFcyt), have important biological functions. Using specific constructs and peptides of human EGF cytoplasmic domain, we demonstrate that EGFcyt facilitates lysosomal and proteasomal protein degradation, and this coincided with growth inhibition of human thyroid and glioma carcinoma cells. EGFcyt and exon 22–23-encoded peptide (EGF22.23) enhanced procathepsin B (procathB) expression and procathB-mediated lysosomal degradation of EGFR/ErbB1 as determined by inhibitors for procathB and the lysosomal ATPase inhibitor BafA1. Presence of mbEGFctF, EGFcyt, EGF22.23, and exon 23-encoded peptides suppressed the expression of the deubiqitinating enzyme ubiquitin C-terminal hydrolase-L1 (UCH-L1). This coincided with hyperubiquitination of total cellular proteins and ErbB1/2 and reduced proteasome activity. Upon small interfering RNA-mediated silencing of endogenously expressed UCH-L1, a similar hyperubiquitinylation phenotype, reduced ErbB1/2 content, and attenuated growth was observed. The exon 23-encoded peptide region of EGFcyt was important for these biologic actions. Structural homology modeling of human EGFcyt showed that this molecular region formed an exposed surface loop. Peptides derived from this EGFcyt loop structure may aid in the design of novel peptide therapeutics aimed at inhibiting growth of cancer cells

Inhibitor of DNA Binding 2 Inhibits Epithelial-Mesenchymal Transition via Up-Regulation of Notch3 in Breast Cancer

Breast cancer is the second leading cause of cancer death in women worldwide. Incurable metastatic breast disease presents a major clinical challenge and is the main cause of breast cancer-related death. The epithelial-mesenchymal transition (EMT) is a critical early promoter of metastasis. In the present study, we identified a novel role for the inhibitor of DNA binding 2 (Id2), a member of the basic helix–loop–helix protein family, during the EMT of breast cancer. Expression of Id2 was positively correlated with Notch3 in breast cancer cells. Low expression of Id2 and Notch3 was associated with worse distant metastasis-free survival in breast cancer patients. The present study revealed that Id2 activated Notch3 expression by blocking E2A binding to an E-box motif in the Notch3 promoter. The Id2-mediated up-regulation of Notch3 expression at both the mRNA and protein levels resulted in an attenuated EMT, which was associated with reduced motility and matrix invasion of ER-positive and -negative human breast cancer cells and the emergence of E-cadherin expression and reduction in the mesenchymal marker vimentin in triple-negative breast cancer cells. In summary, our findings identified Id2 as a suppressor of the EMT and positive transcriptional regulator of Notch3 in breast cancer. Id2 and Notch3 may serve as novel prognostic markers in a subpopulation of ER-positive breast cancer patients

IGF-I: from diagnostic to triple-helix gene therapy of solid tumors.

Alterations in the expression of growth factors and their receptors are associated with the growth and development of human tumors. One such growth factor is IGF-I (insulin-like growth factor I ), a 70-amino-acid polypeptide expressed in many tissues, including brain. IGF-I is also expressed at high levels in some nervous system-derived tumors, especially in glioblastoma. When using IGF-I as a diagnostic marker, 17 different tumors are considered as expressing the IGF-I gene. Malignant glioma, the most common human brain cancer, is usually fatal. Average survival is less than one year. Our strategy of gene therapy for the treatment of gliomas and other solid tumors is based on: 1) diagnostic using IGF-I gene expression as a differential marker, and 2) application of "triple-helix anti-IGF-I " therapy. In the latter approach, tumor cells are transfected with a vector, which encodes an oligoribonucleotide - an RNA strand containing oligopurine sequence which might be capable of forming a triple helix with an oligopurine and/or oligopyrimidine sequence of the promotor of IGF-I gene (RNA-IGF-I DNA triple helix). Human tumor cells transfected in vitro become down-regulated in the production of IGF-I and present immunogenic (MHC-I and B7 expression) and apoptotic characteristics. Similar results were obtained when IGF-I antisense strategy was applied. In both strategies the transfected cells reimplanted in vivo lose tumorigenicity and elicit tumor specific immunity which leads to elimination of established tumors

C1q/TNF‐related peptide 8 (CTRP8) promotes temozolomide resistance in human glioblastoma

The C1q/TNF‐related peptide 8 (CTRP8) has recently emerged as a novel ligand of the G protein‐coupled receptor RXFP1 in the fatal brain tumor glioblastoma (GBM). We previously demonstrated that the CTRP8‐RXFP1 ligand–receptor system promotes motility and matrix invasion of patient GBM and U87 MG cells by specific phosphorylation of PI3 kinase and protein kinase C. Here, we demonstrate a novel role for CTRP8 in protecting human GBM cells against the DNA alkylating damage of temozolomide (TMZ), the standard chemotherapy drug used to treat GBM. This DNA protective role of CTRP8 required a functional RXFP1‐STAT3 signaling cascade in GBM cells. We identified N‐methylpurine DNA glycosylase (MPG), a monofunctional glycosylase that initiates base excision repair pathway by generating an apurinic/apyrimidinic (AP) site, as a new CTRP8‐RXFP1‐STAT3 target in GBM. Upon TMZ exposure, treatment with CTRP8 reduced the formation of AP sites and double‐strand DNA breaks in GBM cells. This CTRP8 effect was independent of cellular MGMT levels and was associated with decreased caspase 3/7 activity and increased survival of human GBM. CTRP8‐induced RXFP1 activation caused an increase in cellular protein levels of the anti‐apoptotic Bcl members and STAT3 targets Bcl‐2 and Bcl‐XL in human GBM. Collectively, our results demonstrate a novel multipronged and clinically relevant mechanism by which the CTRP8‐RXFP1 ligand–receptor system exerts a DNA protective function against TMZ chemotherapeutic stress in GBM. This CTRP8‐RXFP1‐STAT3 axis is a novel determinant of TMZ responsiveness/chemoresistance and an emerging new drug target for improved treatment of human GBM

The Cytoplasmic Domain of proEGF Negatively Regulates Motility and Elastinolytic Activity in Thyroid Carcinoma Cells1

The intracellular domains of the membrane-anchoring regions of some precursors of epidermal growth factor (EGF) family members have intrinsic biologic activities. We have determined the role of the human proEGF cytoplasmic domain (proEGFcyt) as part of the proEGF transmembrane-anchored region (proEGFctF) in the regulation of motility and elastinolytic invasion in human thyroid cancer cells. We found proEGFctF to act as a negative regulator of motility and elastin matrix penetration and the presence of proEGFcyt or proEGF22.23 resulted in a similar reduction in motility and elastinolytic migration. This activity was counteracted by EGF-induced activation of EGF receptor signaling. Decreased elastinolytic migratory activity in the presence of proEGFctF and proEGFcyt/proEGF22.23 coincided with decreased secretion of elastinolytic procathepsin L. The presence of proEGFctF and proEGFcyt/proEGF22.23 coincided with the specific transcriptional up-regulation of t-SNARE member SNAP25. Treatment with siRNA-SNAP25 resulted in motility and elastin migration being restored to normal levels. Epidermal growth factor treatment down-regulated SNAP25 protein by activating EGF receptor-mediated proteasomal degradation of SNAP25. These data provide first evidence for an important function of the cytoplasmic domain of the human proEGF transmembrane region as a novel suppressor of motility and cathepsin L-mediated elastinolytic invasion in human thyroid carcinoma cells and suggest important clinical implications for EGF-expressing tumors

Re-examining advice to complete antibiotic courses: a qualitative study with clinicians and patients

Background: Antibiotic treatment duration may be longer than sometimes needed. Stopping antibiotics early, rather than completing pre-set antibiotic courses, may help reduce unnecessary exposure to antibiotics and antimicrobial resistance (AMR). Aim: To identify clinicians' and patients' views on stopping antibiotics when better (SAWB) for urinary tract infections (UTIs), and to explore comparisons with other acute infections. Design & setting: An exploratory qualitative study with general practice clinicians and patients in England. Method: Primary care clinicians and patients who had recent UTI experience were recruited in England. Remote one-to-one interviews with clinicians and patients, and one focus group with patients, were conducted. Data were audiorecorded, transcribed, and analysed thematically. Results: Eleven clinicians (seven GPs) and 19 patients (14 with experience of recurrent and/or chronic UTIs) were included. All participants considered SAWB unfamiliar and contradictory to well-known advice to complete antibiotic courses, but were interested in the evidence for risks and benefits of SAWB. Clinicians were amenable if evidence and guidelines supported it, whereas patients were more averse because of concerns about the risk of UTI recurrence and/or complications and AMR. Participants viewed SAWB as potentially more appropriate for longer antibiotic courses and other infections (with longer courses and lower risk of recurrence and/or complications). Participants stressed the need for unambiguous advice and SAWB as part of shared decision making and personalised advice. Conclusion: Patients were less accepting of SAWB, whereas clinicians were more amenable to it. Patients and clinicians require good evidence that this novel approach to self-determining antibiotic duration is safe and beneficial. If evidence based, SAWB should be offered with an explanation of why the advice differs from the ‘complete the course’ instruction, and a clear indication of when exactly to stop antibiotics should be given

The C-terminal cytoplasmic domain of human proEGF is a negative modulator of body and organ weights in transgenic mice

AbstractWe generated transgenic mice to study the in vivo role of the cytoplasmic domain of human proEGF (proEGFcyt). Post-pubertal proEGFcyt transgenic (tg) mice displayed an up to 15% reduction in body weight, including smaller kidney and brain weights as compared to control littermates. Renal histology, gene expression profiles, and functional parameters were normal. In both sexes, serum levels of IGFBP-3 were reduced. Circulating IGF-I/IGF-II levels were unchanged. Histomorphological analysis revealed isolated foci of liver necrosis specific to proEGFcyt tg mice. In conclusion, we identified proEGF cytoplasmic domain as a novel modulator of whole body and organ-specific growth in mice