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Abstract Learning Objectives After reading this article, the reader should be able to: Monitor for and treat to prevent bone loss in postmenopausal breast cancer patients receiving an aromatase inhibitor.Describe the methodology of the Z-FAST and ZO-FAST clinical trials.Discuss the effectiveness and tolerability of zoledronic acid when administrated to prevent bone loss associated with aromatase inhibitors. CME This article is available for continuing medical education credit at CME.TheOncologist.com Background. The interim (12-month) results of two similarly designed, ongoing studies (the Zometa®-Femara® Adjuvant Synergy Trials [Z-FAST and ZO-FAST]) suggest that zoledronic acid (4 mg intravenously every 6 months) when initiated with adjuvant letrozole increases bone mineral density (BMD) of the lumbar spine (LS) in postmenopausal women with early-stage breast cancer compared with patients who receive zoledronic acid only when bone loss became clinically significant or a fragility fracture occurred. Methods. An integrated analysis was performed to maximize the value of the large pool of data from the two studies in answering clinically relevant questions. The primary objective was to compare the change in LS BMD at month 12. Secondary objectives included comparing (a) the change in total hip (TH) BMD, (b) changes in bone turnover marker concentrations, (c) time to disease recurrence, and (d) safety at month 12. Findings. The integrated analysis included 1,667 patients. At month 12, LS BMD was 5.2% higher in the upfront group than in the delayed group; TH BMD was 3.5% higher. N-telopeptide and bone-specific alkaline phosphatase concentrations decreased by 21.3% and 12.8% in the upfront group and increased by 21.7% and 24.9% in the delayed group, respectively (p < .0001 for intergroup comparisons). Fewer patients receiving upfront zoledronic acid experienced disease recurrence than patients in the delayed group—seven patients (0.84%) versus 17 patients (1.9%) (p = .0401). Fracture rates were similar. No confirmed osteonecrosis of the jaw was reported. Conclusions. The results of this analysis strengthen the statistical validity of the preliminary results of the Z-FAST and ZO-FAST studies, showing that upfront zoledronic acid prevents aromatase inhibitor–associated bone loss more effectively than delayed-start zoledronic acid in postmenopausal women with early-stage breast cancer receiving letrozole. Additionally, disease recurrence appears to be lower with upfront zoledronic acid, but further follow-up is needed to confirm these interim results.

The role of prostaglandin production in the control of regenerative function of endothelial progenitor cells (EPCs) has not been studied. We hypothesized that activation of cyclooxygenase (COX) enzymatic activity and the subsequent production of prostacyclin (PGI 2 ) is an important mechanism responsible for the regenerative function of EPCs. In the present study, we detected high levels of COX-1 protein expression and PGI 2 biosynthesis in human EPCs outgrown from blood mononuclear cells. Expression of COX-2 protein was almost undetectable under basal conditions but significantly elevated after treatment with tumor necrosis factor-α. Condition medium derived from EPCs hyperpolarized human coronary artery smooth muscle cells, similar to the effect of the PGI 2 analog iloprost. The proliferation and in vitro tube formation by EPCs were inhibited by the COX inhibitor indomethacin or by genetic inactivation of COX-1 or PGI 2 synthase with small interfering (si)RNA. Impaired tube formation and cell proliferation induced by inactivation of COX-1 were rescued by the treatment with iloprost or the selective peroxisome proliferator–activated receptor (PPAR)δ agonist GW501516 but not by the selective PGI 2 receptor agonist cicaprost. Downregulation of PPARδ by siRNA also reduced angiogenic capacity of EPCs. Iloprost failed to reverse PPARδ siRNA-induced impairment of angiogenesis. Furthermore, transfection of PGI 2 synthase siRNA, COX-1 siRNA, or PPARδ siRNA into EPCs decreased the capillary formation in vivo after transplantation of human EPCs into the nude mice. These results suggest that activation of COX-1/PGI 2 /PPARδ pathway is an important mechanism underlying proangiogenic function of EPCs.

Purpose Physical impairments cause profound functional declines in patients with cancer. Although common rehabilitation measures can address many impairments, the extent of their delivery is unknown. We studied these issues by quantifying physical impairments in patients with metastatic breast cancer and by assessing how they are addressed. Patients and Methods A consecutive sample of 163 community-dwelling patients with metastatic breast cancer was stratified by Karnofsky performance score and administered the Medical Outcomes Study Physical Function Subscale and the Older Americans Resource Study Activities of Daily Living subscales. Cancer-related physical impairments were identified through a physical examination, the 6-Minute Walk Test, and the Functional Independence Measure Mobility Subscale. Patients were questioned regarding the nature, type, and setting of treatments for impairments. Physical rehabilitation needs were determined through a consensus process involving physiatrists and physical/occupational therapists specializing in cancer. Results Ninety-two percent of patients (150 of 163) had at least one physical impairment. Among 530 identified impairments, 484 (92%) required a physical rehabilitation intervention and 469 (88%) required physical therapy (PT) and/or occupational therapy (OT). Only 30% of impairments requiring rehabilitation services and 21% of those requiring PT/OT received treatment. Impairments detected during hospitalization were overwhelmingly more likely to receive a rehabilitation intervention (odds ratio [OR] = 87.9; 95% CI, 28.5 to 271.4), and PT/OT (OR = 558.8; 95% CI, 187.0 to 1,669.6). Low socioeconomic and minority status were significantly associated with nontreatment. Conclusion Remediable physical impairments were prevalent and poorly addressed among patients with metastatic breast cancer, drastically so in the outpatient setting. Undertreatment was particularly prominent among minority and socioeconomically disadvantaged groups.

Background— Long-QT syndrome (LQTS) is an inherited disorder associated with sudden cardiac death. The cytoskeletal protein syntrophin-α 1 (SNTA1) is known to interact with the cardiac sodium channel (hNa v 1.5), and we hypothesized that SNTA1 mutations might cause phenotypic LQTS in patients with genotypically normal hNa v 1.5 by secondarily disturbing sodium channel function. Methods and Results— Mutational analysis of SNTA1 was performed on 39 LQTS patients (QTc≥480 ms) with previously negative genetic screening for the known LQTS-causing genes. We identified a novel A257G- SNTA1 missense mutation, which affects a highly conserved residue, in 3 unrelated LQTS probands but not in 400 ethnic-matched control alleles. Only 1 of these probands had a preexisting family history of LQTS and sudden death with an additional intronic variant in KCNQ1. Electrophysiological analysis was performed using HEK-293 cells stably expressing hNa v 1.5 and transiently transfected with either wild-type or mutant SNTA1 and, in neonatal rat cardiomyocytes, transiently transfected with either wild-type or mutant SNTA1. In both HEK-293 cells and neonatal rat cardiomyocytes, increased peak sodium currents were noted along with a 10-mV negative shift of the onset and peak of currents of the current-voltage relationships. In addition, A257G-SNTA1 shifted the steady-state activation ( V h ) leftward by 9.4 mV, whereas the voltage-dependent inactivation kinetics and the late sodium currents were similar to wild-type SNTA1. Conclusion— SNTA1 is a new susceptibility gene for LQTS. A257G- SNTA1 can cause gain-of-function of Na v 1.5 similar to the LQT3.

Background— Mortality in patients with heart failure (HF) remains high, but causes of death are incompletely defined. As HF is a heterogeneous syndrome categorized according to the ejection fraction (EF), the association between EF and causes of death is important, yet elusive. Methods and Results— Community subjects with HF were classified according to the preserved (≥50%) and the reduced EF (<50%). Deaths were classified as due to coronary heart disease and other cardiovascular and noncardiovascular diseases. Among 1063 persons with HF, 45% had preserved EF with fewer cardiovascular risk factors and less coronary disease than those with reduced EF. At 5 years, survival was 45% (95% CI, 43% to 49%), and 43% of the deaths were noncardiovascular. The leading cause of death in subjects with preserved EF was noncardiovascular disease (49%) versus coronary heart disease (43%) for subjects with reduced EF. The proportion of cardiovascular deaths decreased from 69% in 1979–1984 to 40% in 1997–2002 ( P =0.007) among subjects with preserved EF, which is in contrast to a modest change among those with reduced EF (77% to 64%, P =0.08). Advanced age, male sex, diabetes, smoking, and kidney disease were associated with an increased risk of all-cause and cardiovascular deaths. After adjustment, preserved EF was associated with a lower risk of cardiovascular death but not all-cause death. Conclusions— Community subjects with HF experience a persistently high mortality, and a large proportion of deaths is noncardiovascular. Cardiovascular disease before death is less in subjects with preserved EF, and they are less likely to experience cardiovascular deaths compared with those with reduced EF. In those with preserved EF, the proportion of cardiovascular deaths declined over time.