Citations

Patients with cancer often have complex needs that must be met within a short intervention window. The authors highlight opportunities for improved multidisciplinary care for patients with advanced cancer and their families.

Hypoxic vasodilation in skeletal muscle at rest is known to include β-adrenergic receptor-stimulated nitric oxide (NO) release. We previously reported that the augmented skeletal muscle vasodilation during mild hypoxic forearm exercise includes β-adrenergic mechanisms. However, it is unclear whether a β-adrenergic receptor-stimulated NO component exists during hypoxic exercise. We hypothesized that NO-mediated vasodilation becomes independent of β-adrenergic receptor activation with increased exercise intensity during hypoxic exercise. Ten subjects (7 men, 3 women; 23 ± 1 yr) breathed hypoxic gas to titrate arterial O2 saturation to 80% while remaining normocapnic. Subjects performed two consecutive bouts of incremental rhythmic forearm exercise (10% and 20% of maximum) with local administration (via a brachial artery catheter) of propranolol (β-adrenergic receptor inhibition) alone and with the combination of propranolol and nitric oxide synthase inhibition [ NG-monomethyl-l-arginine (l-NMMA)] under normoxic and hypoxic conditions. Forearm blood flow (FBF, ml/min; Doppler ultrasound) and blood pressure [mean arterial pressure (MAP), mmHg; brachial artery catheter] were assessed, and forearm vascular conductance (FVC, ml·min−1·100 mmHg−1) was calculated (FBF/MAP). During propranolol alone, the rise in FVC (Δ from normoxic baseline) due to hypoxic exercise was 217 ± 29 and 415 ± 41 ml·min−1·100 mmHg−1 (10% and 20% of maximum, respectively). Combined propranolol-l-NMMA infusion during hypoxic exercise attenuated ΔFVC at 20% (352 ± 44 ml·min−1·100 mmHg−1; P < 0.001) but not at 10% (202 ± 28 ml·min−1·100 mmHg−1; P = 0.08) of maximum compared with propranolol alone. These data, when integrated with earlier findings, demonstrate that NO contributes to the compensatory vasodilation during mild and moderate hypoxic exercise; a β-adrenergic receptor-stimulated NO component exists during low-intensity hypoxic exercise. However, the source of the NO becomes less dependent on β-adrenergic mechanisms as exercise intensity increases.

Abstract Background: Taxane-induced peripheral neuropathy is a dose-limiting side effect that leads to suboptimal cancer treatment and diminished quality of life. The mode of taxane neurotoxicity is unclear, but may be through stabilization of microtubules and induction of spindle checkpoint, leading to cell cycle arrest at G2/M. Fanconi Anemia (FA) genes, including FANCD2, and FANCA, appear to be involved in G2/M phase checkpoint maintenance as well as spindle checkpoint in response to internal and external signals, such as taxane treatment. Thus, we hypothesized that variants in FA genes could impact severity of taxane-induced neuropathies.Methods: Using DNA extracted from blood collected from 893 breast cancer patients participating in a trial evaluating metronomic dosing of cyclophosphamide, doxorubicin and paclitaxel (S0221), we genotyped for single nucleotide polymorphisms (SNPs) that represent all of the variability across FANCA (44 SNPs) and FANCD2 (24 SNPs) in all race/ethnicity groups, as well as a panel of ancestry informative markers to control for potential population stratification, using Illumina GoldenGate platform. SNPs with minor allele frequency (MAF) less than 0.10 and those out of Hardy Weinberg Equilibrium (HWE) proportions (p&lt;0.001) were removed from analyses. Ordinal regression was used to test for allelic and haplotypic association with grade 3 or 4 toxicities relative to 0, 1, and 2 toxicities, adjusting for age, genetic admixture index and treatment arm. To adjust for multiple testing, permutation analyses were performed on both single SNP and haplotype models.Results: Eighteen SNPs in FANCD2 and 38 SNPs in FANCA passed MAF and HWE proportion requirements. For FANCD2, 4 SNPs spanning 67.5 Kb (rs7648104, rs2272125 [coding SNP], rs6786638 and rs644215), were significantly associated with taxane-induced neuropathy (p&lt;0.001) after controlling for multiple testing, with each SNP resulting in approximately a twofold increase in odds of severe taxane-induced neuropathy. Haplotype estimation showed that all 18 SNPs comprise a single haplotype. Two major (&gt;1% frequency) haplotypes were found. The frequencies of the risk haplotype in cases (patients with grade 3 or 4 neuropathy) and controls (patients with ≤ grade 2 neuropathy) were 0.25 and 0.15, respectively. Ordinal regression analyses were highly significant (p&lt;0.0005); patients with at least one copy of the risk haplotype had more than a twofold increased risk of grade 3 or 4 taxane-induced neuropathy (OR=2.2, 95% CI 1.44, 3.44). For FANCA, no SNPs or haplotypes were significantly associated with grade 3 or 4 neurotoxicity, either prior to or after correction for multiple testing.Conclusions: These results indicate that the Fanconi-Anemia pathway may be important for neurological sensitivity to taxanes, and that genotypic markers might be able to be used to identify patients at increased risk for severe taxane-induced neuropathy. Further studies will elucidate potential associations with survival outcomes. Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 2001.

Abstract Background: MA17 showed that adjuvant letrozole after 5 years of tamoxifen markedly reduced the risk of recurrence in women with ER+ early stage breast cancer and improved overall survival in women presenting with node +ve disease. Most trials of early adjuvant aromatase inhibitor therapy required women to be postmenopausal at diagnosis to be eligible. We report here on a subset of women in the MA17 trial who were premenopausal at initial diagnosis and in whom subsequent menopause, prior to randomization, may have influenced their outcome on extended adjuvant letrozole.Methods: Women randomized to MA17 were divided into 2 groups: 1) pre-menopausal (&lt; 50 years of age but underwent bilateral oophorectomy at time when tamoxifen treatment started or &lt; 50 years of age at the start of tamoxifen treatment but became amenorrheic during adjuvant chemotherapy or tamoxifen treatment) and 2) post-menopausal. Disease-free survival (DFS) from time of randomization for women in these two groups were summarized by Kaplan-Meier curves and compared based on log-rank test and Cox model.Results: 889 women were identified as premenopausal and 4,277 as postmenopausal. Treatment, age, race, duration of tamoxifen, prior adjuvant chemotherapy, and mastectomy were independently associated with menopausal status on multivariate analysis. The interaction between treatment and menopausal status was statistically significant for DFS (p=0.02), indicating that women diagnosed with pre-menopausal breast cancer had significantly greater benefit (Hazard ratio=0.25, 95% CI: 0.12-0.51) with letrozole treatment in terms of DFS than those with post-menopausal status (hazard ratio=0.69 with 95% CI from 0.52 to 0.91). In comparison with women treated with placebo, pre-menopausal women on letrozole had a significantly higher incidence of arthralgia (24 vs. 16%; p=0.004) but a lower incidence of vaginal bleeding (10 vs. 16%; p=0.01). Compared with placebo post-menopausal women receiving letrozole had a higher incidence of hot flashes/flashes (55 vs. 50%; p=0.001), arthralgia (25 vs. 21%; p=0.002), myalgia (15 vs. 12%; p=0.007) and alopecia (5 vs. 3%; p=0.003).Conclusions: Letrozole after tamoxifen was more effective in improving DFS in women who were premenopausal at primary diagnosis than those who were postmenopausal. Letrozole was well tolerated in premenopausal women. These data indicate that women who are premenopausal at the time of diagnosis but become postmenopausal anytime before, or during, adjuvant tamoxifen should be considered for extended adjuvant therapy with letrozole. Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 13.

Abstract Background: African Americans are underrepresented in cancer research trials. We propose that a collaborative effort with African American churches that brings cancer education events and a translational research project to the community with a mobile research unit will facilitate cancer awareness education and increase participation in translational research protocols among African Americans. Methods: From February 2010 through April 2010, Mayo Clinic partnered with predominantly African American Jacksonville churches, with the Volunteers in Medicine Clinic for the working uninsured, and with the local chapter of the Leukemia and Lymphoma Society, to provide 12 education programs focused on five behaviors that reduce cancer risk: proper nutrition, adequate fitness, tobacco cessation, breastfeeding, and limited alcohol consumption. Also offered during these programs was on site access to a translational cancer research pilot project evaluating the prevalence of t(14,18) and monoclonal proteins in African Americans and other racial/ethnic minorities. Translational research participation was facilitated by a mobile research unit (MRU), a converted RV that has sample collection, processing, and storage capabilities. Participants were surveyed on health knowledge and their willingness to participate in research. Results: A total of 236 of 318 participants (74%) returned written questionnaires provided during the education events. Forty-three percent resided in a health zone of Jacksonville that has worse health outcomes compared with any other sections of the city. Eighty-three percent responded that they had some type of health insurance and 88% had a primary care provider. Sixty-seven percent had never received any information on multiple myeloma, and 57% had never received information about clinical research studies. Sixty percent responded that they would participate in research studies and 61 % indicated that they would participate if the research focused on health issues that impacted African Americans. A total of 175 of 318 participants (55%) were enrolled in the translational research feasibility study. Seventy-two percent of the research study participants were female and 77% were African American, 19% Caucasians, and 4% Hispanic or of other racial/ethnic group. Ninety-three percent agreed to have their samples used for research of other health conditions and 85% agreed to have their samples shared with other research institutions. Conclusions: A high rate of participation in a blood collection translational research project was observed among this predominantly African American population. Most participants expressed a positive attitude towards research participation. Partnerships with African American churches in projects that provide community education and bring research to church venues with a mobile research unit are effective in improving health literacy related to a targeted topic, and in increasing translational research participation among African Americans. Funded by Mayo Clinic Comprehensive Cancer Center (NCI grant number P50-CA01508), Mayo Clinic CTSA (NCRR/NIH Grant Number 1 UL1 RR024150) and Active SPORE CA 90297052. Citation Information: Cancer Epidemiol Biomarkers Prev 2010;19(10 Suppl):A38.

Abstract Prior genome-wide association (GWA) studies have identified 10 susceptibility loci for risk of chronic lymphocytic leukemia (CLL). To identify additional loci, we performed a GWA study in 407 CLL cases (of which 102 had a family history of CLL) and 296 controls. Moreover, given the strong familial risk of CLL, we further subset our GWA analysis to the CLL cases with a family history of CLL to identify loci specific to these familial CLL cases. Our top hits from these analyses were evaluated in an additional sample of 252 familial CLL cases and 965 controls. Using all available data, we identified and confirmed an independent association of 4 single-nucleotide polymorphisms (SNPs) that met genome-wide statistical significance within the IRF8 (interferon regulatory factor 8) gene (combined P values ≤ 3.37 × 10−8), located in the previously identified 16q24.1 locus. Subsetting to familial CLL cases, we identified and confirmed a new locus on chromosome 6p21.3 (combined P value = 6.92 × 10−9). This novel region harbors the HLA-DQA1 and HLA-DRB5 genes. Finally, we evaluated the 10 previously reported SNPs in the overall sample and replicated 8 of them. Our findings support the hypothesis that familial CLL cases have additional genetic variants not seen in sporadic CLL. Additional loci among familial CLL cases may be identified through larger studies.

Background— Outcome data for patients receiving implantable cardioverter-defibrillator (ICD) and cardiac resynchronization therapy–defibrillator (CRT-D) devices treated outside of clinical trials are lacking. No clinical trial has evaluated mortality after device implantation or after shock therapy in large numbers of patients with implanted devices that regularly transmit device data over a network. Methods and Results— Survival status in patients implanted with ICD and CRT devices across the United States from a single manufacturer was assessed. Outcomes were compared between patients followed in device clinic settings and those who regularly transmit remote data collected from the device an average of 4 times monthly. Shock delivery and electrogram analysis could be ascertained from patients followed on the network, enabling survival after ICD shock to be evaluated. One- and 5-year survival rates in 185 778 patients after ICD implantation were 92% and 68% and were 88% and 54% for CRT-D device recipients. In 8228 patients implanted with CRT-only devices, survival was 82% and 48% at 1 and 5 years, respectively. For the 69 556 ICD and CRT-D patients receiving remote follow-up on the network, 1- and 5-year survival rates were higher compared with those in the 116 222 patients who received device follow-up in device clinics only (50% reduction; P <0.0001). There were no differences between patients followed on or off the remote network for the characteristics of age, gender, implanted device year or type, and economic or educational status. Shock therapy was associated with subsequent mortality risk for both ICD and CRT-D recipients. Conclusions— Survival after ICD and CRT-D implantation in patients treated in naturalistic practice compares favorably with survival rates observed in clinical trials. Remote follow-up of device data is associated with excellent survival, but arrhythmias that result in device therapy in this population are associated with a higher mortality risk compared with patients who do not require shock therapy.

The purpose of this study was to evaluate the relationship between the cardiac and sympathetic baroreflex sensitivities within healthy, young humans. The sensitivities of the cardiac and sympathetic baroreflexes were compared in 53 normotensive individuals (28 men and 25 women; age: 24.0±0.9 years; body mass index: 24.0±0.3 cm/kg 2 , mean±SEM). Heart rate, arterial blood pressure, and peroneal muscle sympathetic nerve activity were recorded under resting conditions (heart rate: 58±1 bpm; systolic blood pressure: 126±2 mm Hg; diastolic blood pressure: 72±1 mm Hg; mean arterial blood pressure: 89±1 mm Hg; muscle sympathetic nerve activity: 18±1 bursts per min) and during rapid changes in blood pressure induced by sequential boluses of nitroprusside and phenylephrine. Cardiac and sympathetic baroreflex sensitivities were analyzed using the slopes of the linear portions of the muscle sympathetic nerve activity-diastolic blood pressure and R-R interval-systolic blood pressure relationships, respectively. When individual cardiac baroreflex sensitivity was compared with sympathetic baroreflex sensitivity, no correlation (R-R interval: r =−0.13; heart rate: r =0.21) was observed when studied as a group. Analysis by sex unveiled a correlation in women between the cardiac and sympathetic baroreflex sensitivities (R-R interval: r =−0.54; P =0.01; no correlation with hazard ratio: r =0.29). No relationship was found in men (R-R interval: r =0.17; heart rate: r =0.12). These results indicate that, although both cardiac and sympathetic efferents function in baroreflex control of arterial pressure, there is no correlation in their sensitivities within healthy normotensive humans. However, sex-stratified data indicate that sex-based differential correlations might exist.