Tyrosine kinase signalling in breast cancer: Epidermal growth factor receptor and c-Src interactions in breast cancer

Both the non-receptor tyrosine kinase, c-Src, and members of the epidermal growth factor (EGF) receptor family are overexpressed in high percentages of human breast cancers. Because these molecules are plasma membrane-associated and involved in mitogenesis, it has been speculated that they function in concert with one another to promote breast cancer development and progression. Evidence to date supports a model wherein c-Src potentiates the survival, proliferation and tumorigenesis of EGF receptor family members, in part by associating with them. Phosphorylation of the EGF receptor by c-SRC is also critical for mitogenic signaling initiated by the EGF receptor itself, as well as by several G-protein coupled receptors (GPCRs), a cytokine receptor, and the estrogen receptor. Thus, c-Src appears to have pleiotropic effects on cancer cells by modulating the action of multiple growth-promoting receptors

"Talking Around It": A Qualitative Study Exploring Dyadic Congruence in Managing the Uncertainty of Living With a Ventricular Assist Device.

BackgroundVital components of communicating goals of care and preferences include eliciting the patient and caregiver's definition of quality of life, understanding meaningful activities and relationships, and exploring wishes for care at the end of life. Although current literature suggests framing conversations regarding end of life through the lens of meaning and quality of life, there is limited literature exploring dyadic congruence surrounding these important constructs among patients with ventricular assist devices (VADs) and their caregivers.ObjectivesThe purpose of this study was to explore congruence of VAD patient and caregiver perspectives regarding end of life, definitions of quality of life, and meaning in life while managing the uncertainty of living with a VAD.MethodsWe used thematic analysis to analyze semistructured qualitative interviews of 10 patient-caregiver dyads 3 to 12 months after VAD implantation.ResultsThree major themes were identified: (1) differing trajectories of uncertainty and worry, (2) a spectrum of end-of-life perspectives, and (3) enjoying everyday moments and independence. Overall, patients and caregivers had differing perspectives regarding uncertainty and end of life. Within-dyad congruence was most evident as dyads discussed definitions of meaning or quality of life.ConclusionsDyadic perspectives on end of life, meaning in life, and quality of life can inform how palliative care and VAD teams approach conversations about planning for the end of life. Findings from this study can inform future shared decision-making interventions for patients living with VADs and their caregivers

Identification of peplomer cleavage site mutations arising during persistence of MHV-A59

Primary mouse glial cell cultures were infected with mouse hepatitis virus strain A59 (MHV-A59) and maintained over an 18 week period. Viruses isolated from these cultures 16-18 weeks postinfection produce small plaques on fibroblasts and cause only minimal levels of cell-to-cell fusion at times when wild type causes nearly complete cell fusion. However, when mutant- infected cultures were examined 24-36 hours postinfection approximately 90% of the cells were in syncytia showing that the fusion defect is not absolute but rather delayed. Addition of trypsin to mutant-infected cultures enhanced cell fusion a small (2- to 5-fold) but significant degree. Sequencing of portions of the spike genes of six fusion-defective mutants revealed that all contained the same single nucleotide mutation resulting in a substitution of aspartic acid for histidine in the spike cleavage signal. Mutant virions contained only the 180 kDa form of spike protein suggesting that this mutation prevented the normal proteolytic cleavage of the 180 kDa protein into the 90 kDa subunits. Examination of revertants of the mutants supports this hypothesis. Replacement of the negatively-charged aspartic acid with either the wild type histidine or a non-polar amino acid was associated with the restoration of spike protein cleavage and cell fusion