A step-by-step guide to implementing a multidisciplinary endocarditis team

Over the last several years multiple studies, primarily from European centers have demonstrated the clinical and outcomes benefits of multidisciplinary endocarditis teams. Despite this literature, adoption of this approach to patient care has been slower in the United States. While there is literature outlining the optimal composition of an endocarditis team, there is little information to guide providers as they attempt to transform practice from a fragmented, disjointed process to an efficient, collaborative care model. In this review, the authors will outline the steps they took to create and implement a successful multidisciplinary endocarditis team at the University of Michigan. In conjunction with existing data, this piece can be used as a resource for clinicians seeking to improve the care of patients with endocarditis at their institutions.

The Clinical Impact of Implementation of a Multidisciplinary Endocarditis Team

BACKGROUND

Infectious endocarditis is associated with substantial in-hospital mortality of 15-20%. Effective management requires coordination between multiple medical and surgical subspecialties which can often lead to disjointed care. Previous European studies have identified multidisciplinary endocarditis teams as a tool for reducing endocarditis mortality.

METHODS

The multidisciplinary endocarditis Team was formed in May 2018. The group developed an evidence-based algorithm for management of endocarditis that was used to provide recommendations for hospitalized patients over a 1-year period. Mortality outcomes were then retroactively assessed and compared to a historical control utilizing propensity matching.

RESULTS

Between June 2018 and June 2019 the team provided guideline-based recommendations on 56 patients with Duke Criteria definite endocarditis and at least 1 AHA indication for surgery. The historical control included 68 patients with definite endocarditis and surgical indications admitted between July 1^st, 2014 to June 30^th, 2015. In-hospital mortality decreased significantly from 29.4% in 2014-2015 to 7.1% in 2018-2019 (p<0.0001). There was a non-significant increase in the rate of surgical intervention after implementation of the team (41.2% vs 55.4%; p=0.12). Propensity score matching demonstrated similar results.

CONCLUSIONS

Implementation of a multidisciplinary endocarditis team was associated with a significant 1-year decrease in all-cause in-hospital mortality for patients with definite endocarditis and surgical indications, in the presence of notable differences between the two studied cohorts. In conjunction with previous studies demonstrating their effectiveness, this data supports that widespread adoption of endocarditis teams in North America could improve outcomes for this patient population.

713. The Clinical Impact of Implementation of a Multidisciplinary Endocarditis Team

Background

Infectious endocarditis is associated with substantial in-patient mortality of 15-20%. Effective management requires coordination between multiple medical and surgical subspecialties which can often lead to disjointed care. Previous European studies have identified multidisciplinary endocarditis teams as a tool for reducing endocarditis mortality.

Methods

The University of Michigan Multidisciplinary Endocarditis Team was formed on May 3^rd, 2018. The group developed an evidence-based algorithm for management of endocarditis that was used to provide recommendations for hospitalized patients over a 1-year period. Mortality outcomes were then retroactively assessed and compared to a historical control that was identified using an internal research tool.

Figure 1

Table 1

Results

Between June 14^th, 2018 and June 13^th, 2019 the team provided guideline-based recommendations on 56 patients with Duke Criteria definite endocarditis and at least 1 American Heart Association indication for surgery. The historical control included 68 patients with definite endocarditis and surgical indications admitted between July 1^st, 2014 to June 30^th, 2015. In-hospital mortality decreased significantly from 29.4% in 2014-2015 to 7.1% in 2018-2019 (p< 0.0001). There was a non-significant increase in the rate of surgical intervention after implementation of the team (41.2% vs 55.4%; p=0.12).

Table 2

Table 3

Table 4

Conclusion

Implementation of a multidisciplinary endocarditis team was associated with a significant 1-year decrease in all-cause in-hospital mortality for patients with definite endocarditis and surgical indications. In conjunction with previous studies demonstrating their effectiveness, this data supports that widespread adoption of endocarditis teams in North America has the potential to improve outcomes for this patient population.

Table 5

Disclosures

All Authors: No reported disclosures

How Oncologists Perceive the Availability and Quality of Information Generated From Patient-Reported Outcomes (PROs)

Background:

Despite increased incorporation of patient-reported outcome (PRO) measures into clinical trials, information generated from PROs remains largely absent from drug labeling and electronic health records, giving rise to concerns that such information is not adequately informing clinical practice.

Objective:

To evaluate oncologists’ perceptions concerning the availability and quality of information generated from PRO measures. Additionally, to identify whether an association exists between perceptions of availability and attitudes concerning quality.

Method:

An online, 11-item questionnaire was developed to capture clinician perspectives on the availability and use of PRO data to inform practice. The survey also asked respondents to rate information on the basis of 4 quality metrics: “usefulness,” “interpretability,” “accessibility,” and “scientific rigor.”

Results:

Responses were received from 298 of 1301 invitations sent (22.9% response rate). Perceptions regarding the availability of PRO information differed widely among respondents and did not appear to be linked to practice setting. Ratings of PRO quality were generally consistent, with average ratings for the 4 quality metrics between “satisfactory” and “good.” A relationship was observed between ratings of PRO data quality and perceptions of the availability.

Conclusion:

Oncologists’ attitudes toward the quality of information generated from PRO measures are favorable but not enthusiastic. These attitudes may improve as the availability of PRO data increases, given the association we observed between oncologists’ ratings of the quality of PRO information and their perceptions of its availability.

Physician perceptions of a multidisciplinary endocarditis team

Infectious endocarditis is a highly morbid infection that requires coordination of care across medical and surgical specialties, often through the use of a multidisciplinary team model. Multiple studies have demonstrated that such conferences can improve clinical outcomes. However, little is known about physicians' impressions of these groups. We surveyed 126 (response rate of 30%) internal medicine, infectious diseases, cardiology, and cardiac surgery providers 1 year after the implementation of an endocarditis team at the University of Michigan. Ninety-eight percent of physicians felt that the endocarditis team improved communication between specialties. Additionally, over 85% of respondents agreed that the group influenced diagnostic evaluation, reduced management errors, increased access to surgery, and decreased in-hospital mortality for endocarditis patients. These results suggest that multidisciplinary endocarditis teams are valued by physicians as a tool to improve patient care and serve an important role in increasing communication between providers.

Abstract PD2-04: FOXA1 induces a pro-metastatic secretome through ER-dependent and independent transcriptional reprogramming in endocrine-resistant breast cancer

Background: Metastasis in ER-positive (+) breast cancer (BC) occurring years to decades after initial diagnosis presents a daunting challenge for clinical care and preclinical research due to limited known key players and experimental models. FOXA1 is a pioneer factor for ER-chromatin binding and function, and is highly expressed in ER+ BC metastases, yet the underlying mechanism is unclear. Tumor-secreted proteins play a crucial role in the reciprocal interplay between cancer cells and host microenvironmental factors at both primary and secondary sites. We hypothesized that high FOXA1 provokes an ER-dependent transcriptional program that includes a unique pro-tumorigenic secretome essential for promoting ER+ BC metastasis. Methods: A lentiviral doxycycline (Dox)-inducible FOXA1 overexpression vector and a dual luciferase/GFP (LG) tracking vector were integrated to construct a stable MCF7-LG/FOXA1 cell model. Ovariectomized nude mice bearing MCF7-LG/FOXA1 xenografts in the presence of exogenous estrogen (E2) were randomized to ± Dox, each with continued E2, E2 deprivation (ED), or tamoxifen (Tam). Survival surgery removing the therapy-naïve (E2 arm) and relapsed (ED/Tam arms) tumors was performed when tumors reached ∼1000 mm3. All mice then received ED/Tam 'adjuvant' therapy, with longitudinal luminescence imaging to monitor local/distant recurrences. Mice were or will be euthanized at the ethical end-point. Integrative bioinformatics was performed using RNA-seq and FOXA1/ER ChIP-seq data from our preclinical models to identify secretome targets for functional intervention. Times to tumor regression (TTR) and progression (TTP) were defined by when the tumor reached half or twice the volume at randomization. Results: Median (m) TTR was achieved in ED (31/34 days, -/+Dox, P = 0.184) but not in Tam groups — Tam delayed tumor growth but failed to prevent progression in all mice with mTTP of 94/93 days (-/+Dox, P = 0.517). Despite no difference in mTTP at Tam-/+Dox, a quarter of +Dox tumors (3/12) had volume doubled by day 11. No metastases were observed by imaging in any of the mice before surgery ('neoadjuvant' setting). Local relapse and lymph-node/lung metastases were detected after surgery ('adjuvant' setting). At day 90 in the adjuvant Tam group with previously relapsed tumors, +Dox mice succumbed to metastasis more often than -Dox mice (7/8 vs. 3/10, P = 0.023). Compared to the adjuvant Tam+Dox mice with previous therapy-naïve tumors, the Tam+Dox with previously relapsed tumors showed higher distant metastasis rate (7/8 vs. 5/14, P = 0.026). Analysis of the ED setting is pending due to late recurrence. Data integration and functional study revealed a set of cytokines, growth factors, and extracellular matrix components (including IL-8, CTGF, and LOX), regulated by FOXA1 often in conjunction with ER, that are highly involved in FOXA1-induced metastasis. Global secretome profiling by mass spectrometry and target validation are ongoing. Conclusions: FOXA1 overexpression increases metastatic potential in ER+ BC. We established a pertinent metastatic xenograft mouse model to characterize a pro-metastatic secretome with diagnostic and therapeutic potential for treating metastatic ER+ BC.

Citation Format: Fu X, Pereira R, Zhao D, Jung SY, Jeselsohn R, Creighton CJ, Shea M, Nardone A, Angelis CD, Tsimelzon A, Wang T, Gutierrez C, Huang S, Edwards DP, Rimawi MF, Hilsenbeck SG, Brown M, Chen K, Osborne CK, Schiff R. FOXA1 induces a pro-metastatic secretome through ER-dependent and independent transcriptional reprogramming in endocrine-resistant breast cancer [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr PD2-04.

The Prevalence of Angiostrongylus cantonensis/mackerrasae Complex in Molluscs from the Sydney Region

Angiostrongylus cantonensis and Angiostrongylus mackerrasae are metastrongyloid nematodes that infect various rat species. Terrestrial and aquatic molluscs are intermediate hosts of these worms while humans and dogs are accidental hosts. Angiostrongylus cantonensis is the major cause of angiostrongyliasis, a disease characterised by eosinophilic meningitis. Although both A. cantonensis and A. mackerrasae are found in Australia, A. cantonensis appears to account for most infections in humans and animals. Due to the occurrence of several severe clinical cases in Sydney and Brisbane, the need for epidemiological studies on angiostrongyliasis in this region has become apparent. In the present study, a conventional PCR and a TaqMan assay were compared for their ability to amplify Angiostrongylus DNA from DNA extracted from molluscs. The TaqMan assay was more sensitive, capable of detecting the DNA equivalent to one hundredth of a nematode larva. Therefore, the TaqMan assay was used to screen molluscs (n=500) of 14 species collected from the Sydney region. Angiostrongylus DNA was detected in 2 of the 14 mollusc species; Cornu aspersum [14/312 (4.5%)], and Bradybaenia similaris [1/10 (10%)], which are non-native terrestrial snails commonly found in urban habitats. The prevalence of Angiostrongylus spp. was 3.0% ± 0.8% (CI 95%). Additionally, experimentally infected Austropeplea lessoni snails shed A. cantonensis larvae in their mucus, implicating mucus as a source of infection. This is the first Australian study to survey molluscs using real-time PCR and confirms that the garden snail, C. aspersum, is a common intermediate host for Angiostrongylus spp. in Sydney.

Home interventions are effective at decreasing indoor nitrogen dioxide concentrations

Nitrogen dioxide (NO2 ), a by-product of combustion produced by indoor gas appliances such as cooking stoves, is associated with respiratory symptoms in those with obstructive airways disease. We conducted a three-armed randomized trial to evaluate the efficacy of interventions aimed at reducing indoor NO2 concentrations in homes with unvented gas stoves: (i) replacement of existing gas stove with electric stove; (ii) installation of ventilation hood over existing gas stove; and (iii) placement of air purifiers with high-efficiency particulate air (HEPA) and carbon filters. Home inspection and NO2 monitoring were conducted at 1 week pre-intervention and at 1 week and 3 months post-intervention. Stove replacement resulted in a 51% and 42% decrease in median NO2 concentration at 3 months of follow-up in the kitchen and bedroom, respectively (P = 0.01, P = 0.01); air purifier placement resulted in an immediate decrease in median NO2 concentration in the kitchen (27%, P < 0.01) and bedroom (22%, P = 0.02), but at 3 months, a significant reduction was seen only in the kitchen (20%, P = 0.05). NO2 concentrations in the kitchen and bedroom did not significantly change following ventilation hood installation. Replacing unvented gas stoves with electric stoves or placement of air purifiers with HEPA and carbon filters can decrease indoor NO2 concentrations in urban homes.

PRACTICAL IMPLICATIONS

Several combustion sources unique to the residential indoor environment, including gas stoves, produce nitrogen dioxide (NO2), and higher NO2 concentrations, are associated with worse respiratory morbidity in people with obstructive lung disease. A handful of studies have modified the indoor environment by replacing unvented gas heaters; this study, to our knowledge, is the first randomized study to target unvented gas stoves. The results of this study show that simple home interventions, including replacement of an unvented gas stove with an electric stove or placement of HEPA air purifiers with carbon filters, can significantly decrease indoor NO2 concentrations.

Human males appear more prepared than females to resolve conflicts with same-sex peers

The aim of the study was to investigate sex differences in proximate mechanisms that precede the termination of conflicts. In Study 1, we asked women and men to report their intensity of anger in response to hypothetical, common transgressions involving a same-sex roommate. Direct verbal and physical aggression elicited the highest-intensity anger for both sexes, although overall women reported more intense anger than men to all transgressions. In Study 2, we examined sex differences in subjective and physiological reactions to a conflict using a role-playing scenario. Following recall of a conflict involving direct aggression and role-playing a reaction to it, compared with men, women reported their anger would dissipate less quickly and they would take longer to reconcile. Women also exhibited increased heart rate, but little change in cortisol, whereas men exhibited little change in heart rate but increased cortisol production. We interpret the results as indicating that women are less prepared than men to resolve a conflict with a same-sex peer.

Abstract P2-09-08: Therapeutic potential of the dual HER1/2 inhibitor AZD8931 in circumventing endocrine resistance

Background: Crosstalk between ER and HER-family signaling pathways has been suggested to play a role in the development of endocrine resistance. Preclinical studies have shown that AZD8931, a dual tyrosine kinase inhibitor (TKI) of HER1 (EGFR) and HER2, elicits an equipotent inhibition of HER1, HER2, and HER3 signaling, and is consequently more effective in blocking ligand-dependent HER signaling than the dual HER 1/2 TKI lapatinib. Using in vitro and in vivo models we investigated AZD8931's therapeutic potential in enhancing endocrine therapy and in overcoming the growth of tumor cells resistant to tamoxifen (Tam).

Materials and Methods: The effect of different TKIs (AZD8931 and lapatinib) on endocrine therapy [Tam and Fulvestrant (Ful)] was tested in ER+ MCF7 and T47D parental cells and their Tam-resistant derivatives (TamRes). In vitro growth, proliferation, and apoptosis were assessed using an in situ cell cytometer, EDU incorporation, and Annexin V-FITC/c-PARP, respectively. HER ligands in the parental and TamRes cells were profiled using RNASeq analysis of these lines. Western blot analysis was used to analyze the effect of AZD8931, lapatinib, and the HER1 TKI gefitinib on HER 1/2 pathway activation upon ligand stimulation. Nude mice with transplantable MCF7/TamRes xenografts at 200 mm3 were randomized to continued Tam, Tam+AZD8931, Fulvestrant (Ful), or Ful+AZD8931 treatments.

Results: We found that neither lapatinib nor AZD8931 significantly enhanced endocrine sensitivity in parental MCF7 breast cancer cells, although AZD8931 did enhance endocrine sensitivity in parental T47D cells. Furthermore, AZD8931 combined with either Tam or Ful inhibited cell growth more profoundly than lapatinib in the T47D TamRes cell model, and was significantly, though modestly, more potent than lapatinib in the MCF7 TamRes model when combined with Tam. In both TamRes models, AZD8931 significantly inhibited cell proliferation and induced apoptosis, with the highest effects seen in combination with Ful. Interestingly, multiple HER ligands are upregulated in both MCF7 and T47D TamRes models, which could explain the superiority of AZD8931 over lapatinib in these models. Indeed, in EGF and heregulin (HRG) stimulated conditions, AZD8931 more potently inhibited HER signaling (i.e., phosphorylated (p) levels of HER1/2, MAPK, and AKT) than lapatinib or gefitinib. Finally, AZD8931 significantly delayed the growth of MCF7 TamRes xenografts in the presence of continued Tam or Ful. These tumors were also inhibited by Ful alone, but the strongest inhibition was achieved by Ful and AZD8931 in combination. However, despite the marked tumor growth delay, no tumor regression was found in any of these treatments.

Conclusion: This study provides evidence that AZD8931 has greater inhibitory efficacy than lapatinib in endocrine resistant models that are dependent on ligand activation of the HER pathway. Although the AZD8931 combination with Ful robustly slowed growth of TamRes tumors in vivo, the absence of tumor regression suggests that additional escape pathways are also involved and should also be targeted to fully circumvent tamoxifen resistance.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P2-09-08.

Conservative management of an elderly patient with Eisenmenger syndrome

Background

Eisenmenger syndrome (ES) in the adult population has become exceedingly rare in developed countries owing to better recognition and treatment of congenital malformations of the heart. In the absence of transplantation, most patients survive an average of 20-30 years before succumbing to the cardiovascular and hemostatic sequelae. We present a rare case of an elderly woman with ES secondary to an uncorrected atrial-septum defect. She continues to have a high functional capacity despite impressive hemodynamic parameters.

Case

A 69-year-old woman with ES presented to our facility with atrial fibrillation and volume overload. She has a known sinus venosus atrial septal defect and associated severe pulmonary hypertension. She was managed conservatively and discharged on bosentan given her intricate physiology.

Conclusion

Given the similarity of the pathology with idiopathic pulmonary arterial hypertension (IPAH) and ES, drugs that are usually reserved for IPAH such as prostanoids and phosphodiesterase type 5 inhibitors may be beneficial in the management of ES. This case highlights that with our improving understanding of ES, non-operative management may have an expanding role in the care of these complex patients.<Learning objective: Advanced therapy for Eisenmenger syndrome (ES) is geared toward the endothelin-1 mediated pulmonary arterial plexus. Given the similarity of the pathology with idiopathic pulmonary arterial hypertension (IPAH) and ES, drugs that are usually reserved for IPAH such as prostanoids and phosphodiesterase type 5 inhibitors may be beneficial in the management of ES. Conservative management can achieve a favorable outcome, even in elderly patients with advanced disease.>.

Abstract PD01-01: Overcoming endocrine therapy resistance related to PTEN loss by strategic combinations with mTOR, AKT, or MEK inhibitors

Background: Hyperactive PI3K signaling is associated with a more aggressive subtype of estrogen receptor (ER) positive breast cancer (BC) and with endocrine resistance. Loss or downregulation of PI3K's inhibitor PTEN is more common in basal and luminal B vs. luminal A BC. However, the role of PTEN in modulating response to various endocrine therapies is unclear. Here we investigated the effects of PTEN knockdown (KD) on endocrine sensitivity and the potential of multiple kinase inhibitors to restore and improve responses.

Methods: Nude mice bearing ER+ BC xenograft tumors of MCF7 cells stably expressing a doxycycline (Dox)-inducible PTEN-shRNA were randomized to four endocrine treatment groups [continued estrogen (E2) supplementation, or E2-deprivation (ED) alone or in combination with tamoxifen (Tam) or fulvestrant (Ful)]; all -/+ Dox. The effects of single or combined kinase inhibitors on these endocrine treatments -/+ Dox were studied in vitro using inhibitors (i) to mTOR (AZD2014, 0.2 μM), AKT (AZD5363, 1 μM), or MEK (Selumetinib/ARRY-142886, 1 μM). Cell growth, apoptosis, and ER and progesterone receptor (PR) signaling were analyzed using cell cytometry, qRT/PCR, and Western blotting. Synergism tests were used to examine the growth effects of the most promising combinatorial therapy with multiple kinase inhibitors in different endocrine settings.

Results: In wild-type (WT) PTEN xenograft tumors, endocrine therapies were very effective, inducing frequent tumor regression. In PTEN KD tumors endocrine therapies were less effective — PTEN KD delayed tumor regression in all endocrine regimens and accelerated tumor progression in the Tam treated group. Furthermore, at day 250, only 1/8 and 0/7 tumors had developed resistance in the ED and the Ful (−Dox) groups, respectively, while with PTEN KD (+Dox), 7/15 and 5/15 tumors developed resistance to ED and to Ful. In vitro PTEN KD also induced resistance to all endocrine therapies. mRNA and/or protein levels of ER and PR were suppressed by PTEN KD and restored by mTORi and AKTi. In cells with WT PTEN, mTORi was highly effective with or without endocrine therapy. However, AKTi and MEKi were more effective in combination with endocrine therapy. All three inhibitors were less effective upon PTEN KD. The mTORi plus AKTi combination resulted in a potent synergistic inhibition in PTEN KD cells in the presence of E2 or with ED. In contrast, in the presence of Tam, AKTi plus MEKi, independent of PTEN status, was the most effective combination at the doses chosen. Finally, these inhibitors and combinations were more effective in the presence of Ful than ED or Tam in WT PTEN cells. AKTi combined with Ful was still highly effective even in PTEN KD cells, but mTORi and MEKi were less effective.

Conclusions: Our results suggest that PTEN loss renders endocrine therapy less effective in in vitro and in vivo experimental models. Single AKT/MEK kinase inhibitors are more potent in the presence of endocrine therapy. In PTEN KD cells, the activity of all three kinase inhibitors is largely diminished, except for AKTi in the presence of fulvestrant. Kinase inhibitor combinations are generally more effective, but the optimal combinations vary by PTEN status and type of endocrine therapy.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr PD01-01.

Proteolytic activation of the essential parasitophorous vacuole cysteine protease SERA6 accompanies malaria parasite egress from its host erythrocyte

The malaria parasite replicates within an intraerythrocytic parasitophorous vacuole (PV). The PV and host cell membranes eventually rupture, releasing merozoites in a process called egress. Certain inhibitors of serine and cysteine proteases block egress, indicating a crucial role for proteases. The Plasmodium falciparum genome encodes nine serine-repeat antigens (SERAs), each of which contains a central domain homologous to the papain-like (clan CA, family C1) protease family. SERA5 and SERA6 are indispensable in blood-stage parasites, but the function of neither is known. Here we show that SERA6 localizes to the PV where it is precisely cleaved just prior to egress by an essential serine protease called PfSUB1. Mutations that replace the predicted catalytic Cys of SERA6, or that block SERA6 processing by PfSUB1, could not be stably introduced into the parasite genomic sera6 locus, indicating that SERA6 is an essential enzyme and that processing is important for its function. We demonstrate that cleavage of SERA6 by PfSUB1 converts it to an active cysteine protease. Our observations reveal a proteolytic activation step in the malarial PV that may be required for release of the parasite from its host erythrocyte.

P4-01-03: Establishment and Characterization of an Endocrine Resistance Model In Vitro and In Vivo by Inducible PTEN Knockdown

Background

Growth factor receptor and estrogen receptor (ER) are two major driving pathways for initiating and sustaining breast cancer (BC) development and progression. We have previously shown that an inverse correlation exists between the PI3K pathway and ER expression/activity in luminal type BCs. High PI3K activation signaling correlates to the luminal B subtype of BC with low ER expression/activity. However, the involvement of the PI3K pathway tumor suppressor PTEN in resistance to endocrine therapy is less clear. Here we attempt to develop an experimental system to better understand the role of PTEN in this resistance.

Materials and Methods: Two luminal BC cell lines, MCF7L and ZR75-B, were stably infected with a lentivirus pINDUCER (Meerbrey et al., PNAS, 2011), containing Tet-on responsive shPTEN, turboRFP (tRFP) as an inducible tag, and enhanced GFP (eGFP) as a constitutive expressed tag for positive cells selection. Immunoblotting of PTEN, phosphorylated (p) Akt, pMAPK, pc-Jun, ER, and ER's downstream gene products (PR, IGF-1R) was performed on cells after 6 days of doxycycline (Dox) incubation. After pre-starvation for 5 days in estrogen deprivation (ED) conditions, the cells -/+ Dox were subjected to induction with estrogen (E2) or to endocrine treatment [continued ED, tamoxifen (Tam, 10–7M), or fulvestrant (Ful, 10–7M)] in 96-well plate format for 9 days. In situ cell cytometry (Celigo, Cyntellect Inc., San Diego, CA) was applied to count the cell number by scanning the same 96-well plate every other day. Ovariectomized nude mice bearing MCF7L-shPTEN xenografts, established in the presence of E2 supplementation, were randomized to minus and plus Dox groups, with each treatment group continuing E2 or endocrine therapies (ED, Tam, or Ful). The in vivo GFP/RFP imaging was performed with a home-built cooled and image intensified CCD camera system.

Results: Immunoblot analysis showed a striking loss of PTEN, and significant upregulation of pAkt, as well as pMAPK and pc-Jun in cells with +Dox. In contrast, levels of ER, PR and IGF1R were reduced in cells with +Dox compared to -Dox. In all -Dox groups, cell growth was significantly reduced in endocrine treated groups compared to the E2 group, whereas +Dox rescued the endocrine treatment growth suppression, especially in ED and Tam groups. In vivo induction of PTEN shRNA expression was confirmed by RFP imaging after feeding the mice with +Dox water. MCF7L-shPTEN xenografts randomized to +Dox under ED conditions continued to grow over 4 weeks, in contrast to the marked regression of control tumors (−Dox) under this endocrine regimen (p&lt;0.05). Comparison between plus and minus Dox groups under E2, Tam, or Ful treatment is ongoing.

Discussion: These data further support the existence of crosstalk between PI3K and ER pathways in luminal type BC. Decreasing PTEN levels by shRNA renders the luminal type BC cells de novo resistant to endocrine therapy both in vitro and in vivo. The pINDUCER PTEN knockdown system combined with live animal imaging offers successful real-time, noninvasive tracking of endocrine sensitivity by controllably manipulating the level of target gene. Combination therapies to overcome endocrine resistance under PTEN knockdown conditions are currently underway.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P4-01-03.

Developing, Maintaining, and Using a Body of Knowledge for the Massage Therapy Profession

Background:

The diverse field of massage therapy has lacked a formal body of knowledge to serve as a practice and educational foundation and to guide future development. This deficit has hampered the growth of the profession and its acceptance and recognition by the medical and allied health care community.

Purpose:

To provide massage therapists, bodyworkers, physicians, educators, and associated allied health care professionals in the United States with a description of the purpose and development of the massage therapy body of knowledge (MTBOK) and recommendations for its future development and utilization.

Methods:

Professional groups in the massage therapy community came together and established a task force to develop a body of knowledge for the profession. Five groups became the stewards for this effort. A nationwide search produced a task force of eight volunteers from diverse areas of the profession charged with the responsibility of researching and developing the MTBOK document. Review of documents, curricula, state laws and regulations, certification exam content, interviews, and public comment resulted in the development of the MTBOK. During development multiple opportunities for comment and discussion by stakeholders (public) were provided in an effort to create a professional consensus.

Results:

The resulting MTBOK document establishes professional descriptions of the field; scope of practice; knowledge, skills, and abilities for entry-level massage therapists; and definitions for terminology to insure standardization, in order to provide a foundation for future discussion and growth.

Conclusions:

The MTBOK fulfills the goal for which it was developed, to serve as a foundation for the growth and development of the massage therapy profession as a whole. A living document, it should continue to evolve and grow with the profession. Maintenance and continued stewardship of this document by the massage therapy community is vital for continued professional progress.

Abstract P4-02-20: Plasticity of the ER and HER2 Signaling Networks Results in Compensatory Escape Pathways Contributing to Treatment Resistance

Bidirectional crosstalk between the estrogen receptor (ER) and HER2 has been demonstrated in preclinical model systems. We have previously shown in HER2+ breast cancer cells with low ER that potent HER2- targeted therapy results in ER reactivation that functions as an escape pathway to evade therapeutic inhibition. Here we investigated the role of HER pathway components in resistance to endocrine therapies using UACC812 cells, which are endogenously amplified for HER2. Endocrine resistant (R) derivatives of the UACC812 line were developed through long-term (&gt;6 months) culturing with estrogen deprivation (ED) alone or with 4-OH-tamoxifen (Tam, 10-7M). Endocrine treatment [continued ED, estrogen (E2, 10-9M), Tam (10-7M), or fulvestrant (Ful, 10-7M)] of parental cells slowed cell growth compared to estrogen treatment (P&lt;0.01). EDR and TamR derivatives treated with any of the endocrine therapies, however, exhibited the same growth rates as with estrogen, validating the completely resistant phenotype of our clones. By immunoblot analysis, the resistant derivatives, TamR and EDR, showed a striking and complete loss of ER expression and its downstream gene products including PR, IGF-1R, and IRS-1. In contrast, both resistant lines exhibited significant upregulation of HER pathway components including marked increases in total and phosphorylated (p) EGFR, further upregulation of pHER2, and marked increases in the downstream signaling moieties pMAPK, pAkt, pFAK, pSrc, and pFOXO3a. In contrast, levels of pHER3 were markedly reduced at resistance. Since our in vitro data suggested that ER and HER2 compensate for inhibition of each other's pathways, we next examined whether simultaneous inhibition of both pathways can circumvent the development of resistance in an in vivo xenograft model. Athymic nude mice bearing UACC812 xenografts, established in the presence of E2 supplementation, were randomized to continued E2, endocrine therapies alone (ED, Tam, or Ful), anti-HER2 alone [lapatinib (L), trastuzumab (T), or L+T], or the combination of endocrine and anti-HER2 therapies (ED with L, T, or L+T). We found that tumors were stimulated by E2, as well as by Tam (as a mechanism of de novo resistance), while still being inhibited, though only temporarily (2-3 months), by ED and Ful. Anti-HER2 therapy alone only slowed down (L or T) or stabilized (L+T) tumor growth. In contrast, in the presence of both ED and anti-HER2 therapies, most tumors completely regressed. However, only the potent L+T plus ED regimen achieved continuous long term (&gt;200 days) complete regression in all mice. Our results further illustrate the plasticity of the ER and HER2 pathways and provide additional support for the role of the HER network, especially EGFR, in resistance to endocrine therapy in ER+/HER2+ breast cancer. The data emphasize the need for complete HER blockade for optimal therapy.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P4-02-20.

The impact of paroxetine coadministration on stereospecific carvedilol pharmacokinetics

STUDY OBJECTIVE

to assess the impact of paroxetine coadministration on the stereoselective pharmacokinetic (PK) properties of carvedilol.

DESIGN

prospective, randomized, 2-phase crossover.

SETTING

the University of Michigan General Clinical Research Unit and Michigan Clinical Research Unit.

PARTICIPANTS

twelve healthy volunteers aged 18 to 45 years, male and female, receiving no treatment with prescription or nonprescription medications.

INTERVENTIONS

participants received single dose oral carvedilol (12.5 mg) with and without coadministration of immediate-release paroxetine (10 mg orally twice daily), in random order. Blood samples were collected at 0, 0.25, 0.5, 0.75, 1, 1.5, 2, 4, 6, 8, 10, 12, and 24 hours post-carvedilol dose for determination of R and S carvedilol plasma enantiomer concentrations by high pressure liquid chromatography.

MEASUREMENTS AND MAIN RESULTS

pharmacokinetic (PK) parameters were calculated for each enantiomer by noncompartmental methods and compared between study phases by analysis of variance (ANOVA) controlling for study phase order and subject, with Tukey's studentized range test post hoc. Area under the concentration-time curve (AUC) increased significantly with paroxetine coadministration, approximately 2.5-fold and 1.9-fold for the R and S enantiomers, respectively. R/S AUC ratio increased significantly, from approximately 2.3 to 3.0. Individual increases in enantiomeric AUCs with paroxetine coadministration ranged from 0% to 571% and changes in R/S ratio ranged from -8% to 108%. Heart rate, P-R interval, and blood pressure were monitored and no clinically significant changes in carvedilol effects were noted.

CONCLUSION

this study demonstrated a PK drug-drug interaction between paroxetine and carvedilol, with considerable interparticipant variability in carvedilol PK parameters and magnitude of drug interaction. Stereoselectivity of carvedilol metabolism is preserved with paroxetine coadministration, and R/S AUC ratio generally widens. Although this drug interaction could potentially increase adrenergic antagonism and have significant clinical effects in patients, these effects were not seen in our healthy volunteer participants.

Influence of metoprolol dosage release formulation on the pharmacokinetic drug interaction with paroxetine

Studies have demonstrated an influence of dosage release formulations on drug interactions and enantiomeric plasma concentrations. Metoprolol is a commonly used beta-adrenergic antagonist metabolized by CYP2D6. The CYP2D6 inhibitor paroxetine has previously been shown to interact with metoprolol tartrate. This open-label, randomized, 4-phase crossover study assessed the potential differential effects of paroxetine on stereoselective pharmacokinetics of immediate-release (IR) tartrate and extended-release (ER) succinate metoprolol formulations. Ten healthy participants received metoprolol IR (50 mg) and ER (100 mg) with and without paroxetine coadministration. Blood samples were collected over 24 hours for determination of metoprolol plasma enantiomer concentrations. Paroxetine coadministration significantly increased S and R metoprolol area under the plasma concentration-time curve from time 0 to the 24-hour blood draw (AUC(0-24h)) by 4- and 5-fold, respectively for IR, and 3- and 4-fold, respectively, for ER. S/R AUC ratios significantly decreased. These results demonstrate a pharmacokinetic interaction between paroxetine and both formulations of metoprolol. The interaction is greater with R metoprolol, and stereoselective metabolism is lost. This could theoretically result in greater beta-blockade and lost cardioselectivity. The magnitude of the interaction was similar between metoprolol formulations, which may be attributable to low doses/drug input rates employed.

Bone density, strength, and formation in adult cathepsin K (-/-) mice

Cathepsin K (CatK) is a cysteine protease expressed predominantly in osteoclasts, that plays a prominent role in degrading Type I collagen. Growing CatK null mice have osteopetrosis associated with a reduced ability to degrade bone matrix. Bone strength and histomorphometric endpoints in young adult CatK null mice aged more than 10 weeks have not been studied. The purpose of this paper is to describe bone mass, strength, resorption, and formation in young adult CatK null mice. In male and female wild-type (WT), heterozygous, and homozygous CatK null mice (total N=50) aged 19 weeks, in-life double fluorochrome labeling was performed. Right femurs and lumbar vertebral bodies 1-3 (LV) were evaluated by dual-energy X-ray absorptiometry (DXA) for bone mineral content (BMC) and bone mineral density (BMD). The trabecular region of the femur and the cortical region of the tibia were evaluated by histomorphometry. The left femur and sixth lumbar vertebral body were tested biomechanically. CatK (-/-) mice show higher BMD at the central and distal femur. Central femur ultimate load was positively influenced by genotype, and was positively correlated with both cortical area and BMC. Lumbar vertebral body ultimate load was also positively correlated to BMC. Genotype did not influence the relationship of ultimate load to BMC in either the central femur or vertebral body. CatK (-/-) mice had less lamellar cortical bone than WT mice. Higher bone volume, trabecular thickness, and trabecular number were observed at the distal femur in CatK (-/-) mice. Smaller marrow cavities were also present at the central femur of CatK (-/-) mice. CatK (-/-) mice exhibited greater trabecular mineralizing surface, associated with normal volume-based formation of trabecular bone. Adult CatK (-/-) mice have higher bone mass in both cortical and cancellous regions than WT mice. Though no direct measures of bone resorption rate were made, the higher cortical bone quantity is associated with a smaller marrow cavity and increased retention of non-lamellar bone, signs of decreased endocortical resorption. The relationship of bone strength to BMC does not differ with genotype, indicating the presence of bone tissue of normal quality in the absence of CatK.

Individual and combined effects of exercise and alendronate on bone mass and strength in ovariectomized rats

Exercise and bisphosphonate therapies increase bone strength by primarily increasing bone formation and reducing resorption, respectively. Based on these different mechanisms of action, it is possible that combined introduction of exercise and bisphosphonate therapies generates greater improvements in bone mass and strength than either intervention alone. The aim of this study was to examine the individual and combined effects of exercise (treadmill running) and bisphosphonate therapy (alendronate [ALN]) on bone mass and strength in ovariectomized (OVX) rats. Seven-month-old virgin female rats were randomly assigned to either a sham-OVX group (n=13) or one of four OVX groups: vehicle-treated cage-control (VEH-CON, n=10); ALN-treated cage-control (ALN-CON, n=13); vehicle-treated plus treadmill running (VEH-RUN, n=13); and ALN-treated plus treadmill running (ALN-RUN, n=13). ALN-treated groups received twice-weekly ALN (0.015 mg/kg), and exercise groups ran on a motorized treadmill at a 5% incline for 60 min/day, 22-24 m/min, 5 days/week. In vivo measurements included dual-energy X-ray absorptiometry (DXA) of whole-body bone mineral content (BMC), and ex vivo measurements included DXA, micro-computed tomography (muCT), and mechanical testing of the femur and L4 vertebrae. After 14 weeks of intervention, exercise and ALN had additive benefits on whole body and proximal femur BMC, cross-sectional area of the L4 vertebrae, and mechanical properties of the mid-shaft femur. In comparison, for total and mid-shaft femur BMC, L4 vertebrae BMC, and mid-shaft femur cortical thickness and area, there were significant exercise and ALN interactions indicating that the two interventions worked in synergy to enhance bone properties. Supporting the contention that ALN and exercise function via distinct mechanisms of action, ALN successfully reduced medullary canal area suggesting it reduced endocortical bone resorption, whereas exercise augmented periosteal perimeter suggesting it stimulated periosteal bone formation. In summary, we found combined treadmill running and ALN to be more beneficial in preventing declines in bone mass and strength following OVX than the introduction of either intervention alone. These data suggest that a comprehensive program of bisphosphonate therapy and weight-bearing exercise may be an effective method for preventing and treating osteoporosis in post-menopausal women.

A Family of Aspartic Proteases and a Novel, Dynamic and Cell-Cycle-Dependent Protease Localization in the Secretory Pathway of Toxoplasma gondii

Aspartic proteases are important virulence factors in pathogens like HIV, Candida albicans or Plasmodium falciparum. We report here the identification of seven putative aspartic proteases, TgASP1 to TgASP7, in the apicomplexan parasite Toxoplasma gondii. Bioinformatic and phylogenetic analysis of the TgASPs and other aspartic proteases from related Apicomplexa suggests the existence of five distinct groups of aspartic proteases with different evolutionary lineages. The members of each group share predicted biological features that validate the phylogeny. TgASP1 is expressed in tachyzoites, the rapidly dividing asexual stage of T.gondii. We present the proteolytic maturation and subcellular localization of this protease through the cell cycle. TgASP1 shows a novel punctate localization associated with the secretory system in non-dividing cells, and relocalizes dramatically and unambiguously to the nascent inner membrane complex of daughter cells at replication, before coalescing again at the end of division.

Comparison of hepatitis C treatment patterns in patients with and without psychiatric and/or substance use disorders

Hepatitis C virus (HCV) infection is more frequent in veterans than in nonveterans. Up to 85% of HCV-infected veterans have psychiatric and/or substance use (SU) co-morbidities which, prior to the 2002 NIH Consensus Conference, were considered relative contraindications to antiviral therapy, assuming a poor adherence. With the objective of evaluating the validity of this assumption, we compared eligibility, completion and response to antiviral therapy in HCV-infected veterans with and without these comorbidities. Veterans who were anti-HCV-positive and had been seen at least once in the liver clinic (between October 1999 and June 2002) were identified through the CT-VAHCS database. Records were reviewed for patient demographics and status of liver disease, assessment of treatment eligibility, type of therapy, completion of therapy and virological response. Patients with active mental illness (MI) or SU were compared with those without these comorbidities (controls). Of 697 anti-HCV-positive-patients, 647 HCV-RNA-positive patients were included, 294 with MI/SA and 353 controls. Patient demographics, viral and liver disease characteristics were comparable between groups. Patients with MI/SA were considered ineligible for therapy more frequently (53%vs 39%, P < 0.001) and were treated less frequently (21%vs 28%, P = 0.03) than controls. However, completion of therapy (72%vs 59%) and sustained virological response (SVR) (20%vs 25%) did not differ significantly between groups. HCV-infected veterans with MI/SA are being offered therapy and treated less often than those without such co-morbidities, however therapy completion and SVR rates are similar, challenging the perception that adherence is poorer in this patient population.