Publications

PURPOSE

The purpose of this qualitative study was to evaluate breast cancer survivors' (BCS) responses to a self-management survivorship care transition intervention in the formative development of such an intervention. The experience of BCS is marked by uncertainty and anxiety about subsequent care, and a desire for more information about future care needs and late effects of treatment. Self-management strategies have demonstrated improved outcomes in chronic illness, and may address the unmet needs of breast cancer survivors.

METHODS AND SAMPLE

Five focus and discussion groups each were conducted at a single site in the Southeastern United States with a total of twenty breast cancer survivors. BCS were presented with a description of a survivorship transition intervention that encouraged self-management. Groups were led by a trained moderator using a semi-structured guide with 7 open-ended questions about their care transition experience and response to the proposed intervention. A theoretically-derived, concept-guided coding strategy was developed after review of transcripts. Iterative constant comparative methods were used to ensure that transcripts were reviewed exhaustively for emerging codes and relationships.

KEY RESULTS

Three dominant themes emerged around readiness for self-management: 1) the breast cancer experience as a catalyst for self-management; 2) fear of recurrence as a catalyst for self-management; and 3) the impact of the meaning of breast cancer on individual readiness for self-management.

CONCLUSIONS

These findings contribute to further development of a conceptual model and interventions built on BCS self-management to improve the survivorship experience.

Idiopathic pulmonary fibrosis (IPF) is an incurable condition that is characterized by progressive pulmonary fibrosis, architectural distortion of the lung and loss of gas exchange units. Until recently, there was no effective treatment for this condition. However, there were two landmark trials published earlier this year, which have changed the management of this condition. Pirfenidone (Assessment of Pirfenidone to Confirm Efficacy and Safety in Idiopathic Pulmonary Fibrosis trial) and nintedanib (Efficacy and Safety of Nintedanib in Idiopathic Pulmonary Fibrosis-1 and -2 trials) have both demonstrated positive outcomes in patients with IPF. In this perspective, we critically discuss the role of these agents in IPF and in the broader pulmonary fibrosis population.

BACKGROUND

Healthcare-associated Legionnaires' disease (LD) is a preventable pneumonia with a 30% case fatality rate. The Centers for Disease Control and Prevention guidelines recommend a high index of suspicion for the diagnosis of healthcare-associated LD. We characterized an outbreak and evaluated contributing factors in a hospital using copper-silver ionization for prevention of Legionella growth in water.

METHODS

Through medical records review at a large, urban tertiary care hospital in November 2012, we identified patients diagnosed with LD during 2011-2012. Laboratory-confirmed cases were categorized as definite, probable, and not healthcare associated based on time spent in the hospital during the incubation period. We performed an environmental assessment of the hospital, including collection of samples for Legionella culture. Clinical and environmental isolates were compared by genotyping. Copper and silver ion concentrations were measured in 11 water samples.

RESULTS

We identified 5 definite and 17 probable healthcare-associated LD cases; 6 case patients died. Of 25 locations (mostly potable water) where environmental samples were obtained for Legionella-specific culture, all but 2 showed Legionella growth; 11 isolates were identical to 3 clinical isolates by sequence-based typing. Mean copper and silver concentrations were at or above the manufacturer's recommended target for Legionella control. Despite this, all samples where copper and silver concentrations were tested showed Legionella growth.

CONCLUSIONS

This outbreak was linked to the hospital's potable water system and highlights the importance of maintaining a high index of suspicion for healthcare-associated LD, even in the setting of a long-term disinfection program.

Clearing cellular debris after brain injury represents an important mechanism in regaining tissue homeostasis and promoting functional recovery. Triggering receptor expressed on myeloid cells-2 (TREM2) is a newly identified receptor expressed on microglia and is thought to phagocytose damaged brain cells. The precise role of TREM2 during ischemic stroke has not been fully understood. We explore TREM2 in both in vitro and in vivo stroke models and identify a potential endogenous TREM2 ligand. TREM2 knockdown in microglia reduced microglial activation to an amoeboid phenotype and decreased the phagocytosis of injured neurons. Phagocytosis and infarcted brain tissue resorption was reduced in TREM2 knock-out (KO) mice compared with wild-type (WT) mice. TREM2 KO mice also had worsened neurological recovery and decreased viable brain tissue in the ipsilateral hemisphere. The numbers of activated microglia and phagocytes in TREM2 KO mice were decreased compared with WT mice, and foamy macrophages were nearly absent in the TREM2 KO mice. Postischemia, TREM2 was highly expressed on microglia and TREM2-Fc fusion protein (used as a probe to identify potential TREM2 binding partners) bound to an unknown TREM2 ligand that colocalized to neurons. Oxygen glucose deprivation-exposed neuronal media, or cellular fractions containing nuclei or purified DNA, but not cytosolic fractions, stimulated signaling through TREM2. TREM2-Fc fusion protein pulled down nucleic acids from ischemic brain lysate. These findings establish the relevance of TREM2 in the phagocytosis of the infarcted brain and emphasize its role in influencing neurological outcomes following stroke. Further, nucleic acids may be one potential ligand of TREM2 in brain ischemia.

INTRODUCTION

The emergence of hormone therapy resistance, despite continued expression of the estrogen receptor (ER), is a major challenge to curing breast cancer. Recent clinical studies suggest that epigenetic modulation by histone deacetylase (HDAC) inhibitors reverses hormone therapy resistance. However, little is known about epigenetic modulation of the ER during acquired hormone resistance. Our recent phase II study demonstrated that HDAC inhibitors re-sensitize hormone therapy-resistant tumors to the anti-estrogen tamoxifen. In this study, we sought to understand the mechanism behind the efficacy of this combination.

METHODS

We generated cell lines resistant to tamoxifen, named TAMRM and TAMRT, by continuous exposure of ER-positive MCF7 and T47D cells, respectively to 4-hydroxy tamoxifen for over 12 months. HDAC inhibition, along with pharmacological and genetic manipulation of key survival pathways, including ER and Bcl-2, were used to characterize these resistant models.

RESULTS

The TAMRM cells displayed decreased sensitivity to tamoxifen, fulvestrant and estrogen deprivation. Consistent with previous models, ER expression was retained and the gene harbored no mutations. Compared to parental MCF7 cells, ER expression in TAMRM was elevated, while progesterone receptor (PGR) was lost. Sensitivity of ER to ligands was greatly reduced and classic ER response genes were suppressed. This model conveyed tamoxifen resistance through transcriptional upregulation of Bcl-2 and c-Myc, and downregulation of the cell cycle checkpoint protein p21, manifesting in accelerated growth and reduced cell death. Similar to TAMRM cells, the TAMRT cell line exhibited substantially decreased tamoxifen sensitivity, increased ER and Bcl-2 expression and significantly reduced PGR expression. Treatment with HDAC inhibitors reversed the altered transcriptional events and reestablished the sensitivity of the ER to tamoxifen resulting in substantial Bcl-2 downregulation, growth arrest and apoptosis. Selective inhibition of Bcl-2 mirrored these effects in presence of an HDAC inhibitor.

CONCLUSIONS

Our model implicates elevated ER and Bcl-2 as key drivers of anti-estrogen resistance, which can be reversed by epigenetic modulation through HDAC inhibition.