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1.
Solid State Nucl Magn Reson ; 131: 101935, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38603990

RESUMO

The NMR lineshapes produced by half-integer quadrupolar nuclei are sensitive to 11 distinct fit parameters per inequivalent site. To date, automatic fitting routines have failed to replace manual parameter insertion and evaluation due to the importance of local minima and the need for fitting multiple-field magic-angle spinning (MAS) and static spectra simultaneously. Herein we introduce a new tool, AMES-Fit (Automatic Multiple Experiment Simulation and Fitting), to automatically find the global best-fit simulation parameters for a series of multiple-field NMR lineshapes. AMES-Fit uses an adaptive step size random search algorithm to dynamically probe parameter space and requires minimal human input. The best fits are obtained in a few minutes of computation time that would otherwise have required several person-hours of work. The program is freely available and open-source.

2.
J Am Chem Soc ; 145(5): 2901-2910, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36696148

RESUMO

C-H/Et-Al exchange in zirconium-catalyzed reactions of saturated hydrocarbons and AlEt3 affords versatile organoaluminum compounds and ethane. The grafting of commercially available Zr(OtBu)4 on silica/alumina gives monopodal ≡SiO-Zr(OtBu)3 surface pre-catalyst sites that are activated in situ by ligand exchange with AlEt3. The catalytic C-H alumination of dodecane at 150 °C followed by quenching in air affords n-dodecanol as the major product, revealing selectivity for methyl group activation. Shorter hydrocarbon or alcohol products were not detected under these conditions. Catalytic reactions of cyclooctane and AlEt3, however, afford ring-opened products, indicating that C-C bond cleavage occurs readily in methyl group-free reactants. This selectivity for methyl group alumination enables the C-H alumination of polyethylenes, polypropylene, polystyrene, and poly-α-olefin oils without significant chain deconstruction. In addition, the smallest hydrocarbon, methane, undergoes selective mono-alumination under solvent-free catalytic conditions, providing a direct route to Al-Me species.

3.
Breast Cancer Res Treat ; 192(1): 153-161, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35112166

RESUMO

BACKGROUND: The NSABP B-36 compared four cycles of doxorubicin and cyclophosphamide (AC) with six cycles of 5-fluorouracil, epirubicin, and cyclophosphamide (FEC-100) in node-negative early-stage breast cancer. A sub-study within B-36, focusing on symptoms, quality of life (QOL), menstrual history (MH), and cardiac function (CF) was conducted. PATIENTS AND METHODS: Patients completed the QOL questionnaire at baseline, during treatment, and every 6 months through 36 months. FACT-B Trial Outcome Index (TOI), symptom severity, and SF-36 Vitality and Physical Functioning (PF) scales scores were compared between the two groups using a mixed model for repeated measures analysis. MH was collected at baseline and subsequently assessed if menstrual bleeding occurred within 12 months prior to randomization. Post-chemotherapy amenorrhea outcome was examined at 18 months and was defined as lack of menses in the preceding year. Logistic regression was used to test for association of amenorrhea and treatment. CF assessment was done at baseline and 12 months. Correlation analysis was used to address associations between changes in baseline and 12-month PF and concurrent CF changes measured by LVEF. RESULTS: FEC-100 patients had statistically significantly lower TOI scores during chemotherapy (P = 0.02) and at 6 months (P < 0.001); lower Vitality score at 6 months (P < 0.01), and lower PF score during the first year than AC patients. There were no statistically significant QOL score differences between the two groups beyond 12 months. No significant differences in symptom severity between the two groups were observed. Rates of amenorrhea were significantly different between FEC-100 and AC (67.4% vs. 59.1%, P < 0.001). There was no association between changes in LVEF and PF (P = 0.38). CONCLUSIONS: Statistically significant QOL differences between the two groups favored AC; however, the magnitude was small and unlikely to be clinically meaningful. There was a clinical and statistically significant difference in risk for amenorrhea, favoring AC. TRIAL REGISTRY: NCT00087178; Date of registration: 07/08/2004.


Assuntos
Neoplasias da Mama , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias da Mama/tratamento farmacológico , Quimioterapia Adjuvante , Ciclofosfamida/efeitos adversos , Doxorrubicina/efeitos adversos , Epirubicina/efeitos adversos , Feminino , Fluoruracila/efeitos adversos , Humanos , Avaliação de Resultados em Cuidados de Saúde , Qualidade de Vida
4.
Breast Cancer Res Treat ; 193(3): 555-564, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35230585

RESUMO

PURPOSE: Results from adjuvant trials evaluating 6 cycles of epirubicin-based chemotherapy regimens suggested these programs may be more effective than 4 cycles of doxorubicin-based chemotherapy. METHOD: NSABP B-36 was a phase III clinical trial originally designed as a 2 × 2 factorial study comparing 6 cycles of 5-FU, epirubicin, and cyclophosphamide (FEC-100) to 4 cycles of conventional doxorubicin and cyclophosphamide (AC) with celecoxib or placebo. Shortly after activation, concerns regarding increased cardiovascular risks among selective COX-2 inhibitors resulted in a decision to remove the celecoxib/placebo from the trial. Women with histologically node-negative invasive breast cancer who had undergone primary surgery with a lumpectomy or total mastectomy were eligible. Primary endpoint was disease-free survival (DFS). RESULTS: Between May 2004 and July 2008, 2722 patients were enrolled. Administration of FEC-100 did not result in improvement in DFS compared to AC (HR 1.09; 95% CI 0.92-1.29, p value = 0.31). The effect of FEC-100 compared to AC on DFS was significantly different for receptor-positive (HR 1.32, 95% CI 1.05-1.66) compared to receptor-negative patients (HR 0.86, 95% CI 0.66-1.11) (treatment-by-receptor status interaction p value = 0.02). There was no statistically significant difference in the effect of treatment on overall survival (OS) with FEC-100 compared to AC (HR 1.06; 95% CI 0.84-1.35, p value = 0.61). Overall, Grade 3 and 4 adverse events were more frequent in the FEC-100 group. CONCLUSION: The results of B-36 do not support use of six-cycle anthracycline-based regimens in node-negative breast cancer. Prolongation of anthracycline-based therapy with FEC-100 does not improve DFS or OS, relative to AC for 4 cycles, and was associated with expected increases in toxicity. A statistically significant interaction between treatment and hormone receptor status favoring AC in hormone-receptor-positive breast cancers is consistent with the hypothesis that optimal duration of chemotherapy may be four cycles in these patients. Late cardiac events and deaths prior to recurrence or second cancer were infrequent on both arms, but slightly higher with FEC-100. TRIAL REGISTRATION: ClinicalTrials.gov: NCT00087178.


Assuntos
Neoplasias da Mama , Antraciclinas/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Celecoxib/uso terapêutico , Quimioterapia Adjuvante , Ciclofosfamida , Intervalo Livre de Doença , Doxorrubicina/efeitos adversos , Epirubicina , Feminino , Fluoruracila , Humanos , Mastectomia
5.
Inorg Chem ; 61(2): 1067-1078, 2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-34962783

RESUMO

The immobilization of molecularly precise metal complexes to substrates, such as silica, provides an attractive platform for the design of active sites in heterogeneous catalysts. Specific steric and electronic variations of the ligand environment enable the development of structure-activity relationships and the knowledge-driven design of catalysts. At present, however, the three-dimensional environment of the precatalyst, much less the active site, is generally not known for heterogeneous single-site catalysts. We explored the degree to which NMR-based surface-to-complex interatomic distances could be used to solve the three-dimensional structures of three silica-supported metal complexes. The structure solution revealed unexpected features related to the environment around the metal that would be difficult to discern otherwise. This approach appears to be highly robust and, due to its simplicity, is readily applied to most single-site catalysts with little extra effort.

6.
Oncologist ; 26(8): e1290-e1295, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33942937

RESUMO

Although it is accepted that oncologists should plan for a future beyond full-time oncology, there is little practical guidance for a successful transition into retirement. Previously, we provided strategies for various aspects of retirement planning. However, this became significantly more complicated as we face newer issues such as the COVID-19 pandemic, the move to virtual patient care, greater awareness of burnout, and the increasing burden of regulatory issues such as the electronic medical record. It is evident that more prospective information is needed to guide oncologists in planning their retirement.


Assuntos
COVID-19 , Aposentadoria , Humanos , Pandemias , Estudos Prospectivos , SARS-CoV-2
7.
Support Care Cancer ; 29(5): 2509-2517, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-32929540

RESUMO

PURPOSE: Bisphosphonates reduce bone metastases in postmenopausal women with early-stage breast cancer but carry the risk of bisphosphonate-related osteonecrosis of the jaw (BRONJ). We describe risk factors for BRONJ and compare BRONJ provoked by infection or trauma with spontaneous lesions, which carry a better prognosis. METHODS: SWOG 0307 randomized women with stage I-III breast cancer to receive zoledronic acid (ZA), clodronate (CL), or ibandronate (IB) for 3 years, implemented BRONJ prevention guidelines, and collected information about dental health and development of BRONJ. All statistical tests were two-sided. RESULTS: Of 6018 women, 48 developed BRONJ. Infection was present in 21 (43.8%). Median time to BRONJ was 2.1 years for ZA, 2.0 years for IB, and 3.4 years for clodronate (p = 0.04). BRONJ was associated with bisphosphonate type (28/2231 (1.26%) for ZA, 8/2235 (0.36%) for CL, 12/1552 (0.77%) for IB), dental calculus (OR 2.03), gingivitis (OR 2.11), moderate/severe periodontal disease (OR 2.87), and periodontitis > 4 mm (OR 2.20) (p < 0.05). Of 57 lesions, BRONJ occurred spontaneously in 20 (35.1%) and was provoked by dental extraction in 20 (35.1%), periodontal disease in 14 (24.6%), denture trauma in 6 (10.5%), and dental surgery in 2 (3.5%). Spontaneous BRONJ occurred more frequently at the mylohyoid ridge. There were no differences in dental disease, infection, or bisphosphonate type between spontaneous and provoked BRONJ. CONCLUSION: ZA and worse dental health were associated with increased incidence of BRONJ, with a trend toward additive risk when combined. BRONJ incidence was lower than in similar studies, with prevention strategies likely linked to this. CLINICAL TRIAL NUMBER: NCT00127205 REGISTRATION DATE: July 2005.


Assuntos
Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/etiologia , Neoplasias da Mama/tratamento farmacológico , Quimioterapia Adjuvante/efeitos adversos , Difosfonatos/efeitos adversos , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/patologia , Conservadores da Densidade Óssea/efeitos adversos , Feminino , Humanos , Prognóstico , Estudos Prospectivos , Fatores de Risco
8.
Solid State Nucl Magn Reson ; 111: 101712, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33450713

RESUMO

γ-encoded recoupling sequences are known to produce strong amplitude modulations that lead to sharp doublets when Fourier transformed. These doublets depend very little on the recoupled tensor asymmetry and thus enable for the straightforward determination of dynamic order parameters. It can, however, be difficult to measure small anisotropies, or small order parameters, using such sequences; the resonances from the doublet may overlap with each other, or with the zero-frequency glitch. This limitation has prevented the widespread use of 1H chemical shift anisotropy (CSA) for the measurement of dynamics, particularly for CH protons which typically have CSAs of only a few ppm when immobile. Here, we introduce a simple modification to the traditional 1H CSA and proton-detected local field pulse sequences that enables the acquisition of a hypercomplex dataset and the removal of the uncorrelated magnetization that results in the zero-frequency glitch. These new sequences then yield a frequency shift in the indirect dimension, rather than a splitting, which is easily identifiable even in cases of weak interactions.


Assuntos
Prótons , Anisotropia
9.
Oncologist ; 22(1): 12-24, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27864574

RESUMO

Breast cancer (BC) is the most common malignancy in women worldwide, with approximately two-thirds having hormone receptor-positive (HR+) tumors. New endocrine therapy (ET) strategies include combining ET agents as well as adding inhibitors targeting growth factors, angiogenesis, the mechanistic target of rapamycin, phosphoinositide 3-kinase (PI3K), or cyclin-dependent kinase 4/6 to ET. Level 1 evidence supports use of fulvestrant plus anastrozole or palbociclib plus letrozole as first-line therapy for HR+/HER- advanced BC with special consideration for the former in ET-naïve patients, as well as everolimus plus exemestane or palbociclib plus fulvestrant as second-line therapy with special consideration in select first-line patients. Although the safety profiles of these combinations are generally predictable and manageable, both everolimus and palbociclib are associated with an increased risk of potentially serious or early-onset toxicities requiring individualized a priori adverse event risk stratification, earlier and more rigorous agent-specific monitoring, and patient education. Although each of these combinations improves progression-free survival, none with the exception of anastrazole plus fulvestrant have demonstrated improved overall survival. PI3K catalytic-α mutations assessed from circulating tumor DNA represent the first potentially viable serum biomarker for the selection of ET combinations, and new data demonstrate the feasibility of this minimally invasive technique as an alternative to traditional tissue analysis. Therapeutic ratios of select ET combinations support their use in first- and second-line settings, but optimal sequencing has yet to be determined. THE ONCOLOGIST: 2017;22:12-24 IMPLICATIONS FOR PRACTICE: Emerging data show that new endocrine therapy (ET) combinations can improve progression-free and overall survival outcomes in patients with hormone receptor-positive, HER2-negative (HR+/HER-) advanced breast cancer. Level 1 evidence supports consideration of dual ET regimens, particularly in ET-naïve patients, or palbociclib plus letrozole as first-line therapy, as well as the addition of mTOR or CDK4/6 inhibitors to established ET in the second-line setting and in select first-line patients. Some combinations are associated with increased risk of class-specific toxicities that will require individualized risk stratification, earlier and more rigorous agent-specific monitoring, and patient education. Recent data on a noninvasive biomarker assay that predicts response to a phosphoinositide 3-kinase inhibitor demonstrates the feasibility of this minimally invasive technique as an alternative to traditional tissue analysis.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias da Mama/sangue , Neoplasias da Mama/tratamento farmacológico , Nitrilas/administração & dosagem , Proteínas Nucleares/genética , Fatores de Transcrição/genética , Triazóis/administração & dosagem , Anastrozol , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Biomarcadores Tumorais/sangue , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , DNA Tumoral Circulante/sangue , Intervalo Livre de Doença , Estradiol/administração & dosagem , Estradiol/efeitos adversos , Estradiol/análogos & derivados , Feminino , Fulvestranto , Humanos , Letrozol , Mutação , Células Neoplásicas Circulantes/metabolismo , Nitrilas/efeitos adversos , Proteínas Nucleares/sangue , Piperazinas/administração & dosagem , Piperazinas/efeitos adversos , Pós-Menopausa/sangue , Piridinas/administração & dosagem , Piridinas/efeitos adversos , Receptor ErbB-2/genética , Receptores de Estrogênio/genética , Fatores de Transcrição/sangue , Triazóis/efeitos adversos
11.
Ann Surg Oncol ; 24(2): 398-406, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27663567

RESUMO

BACKGROUND: Isolated locoregional recurrences (ILRRs) of breast cancer confer a significant risk for the development of distant metastasis. Management practices and second ILRR events in the Chemotherapy as Adjuvant for LOcally Recurrent breast cancer (CALOR) trial were investigated. METHODS: In this study, 162 patients with ILRR were randomly assigned to receive postoperative chemotherapy or no chemotherapy. Descriptive statistics characterize outcomes according to local therapy and the influence of hormone receptor status on subsequent recurrences. Competing risk regression models, Kaplan-Meier estimates, and Cox proportional hazards models were used to evaluate associations between treatment, site of second recurrence, and outcome. RESULTS: The median follow-up period was 4.9 years. Of the 98 patients who received breast-conserving primary surgery 89 had an ipsilateral-breast tumor recurrence. Salvage mastectomy was performed for 73 patients and repeat lumpectomy for 16 patients. Another eight patients had nodal ILRR, and one patient had chest wall ILRR. Among 64 patients whose primary surgery was mastectomy, 52 had chest wall/skin ILRR, and 12 had nodal ILRR. For 15 patients, a second ILRR developed a median of 1.6 years (range 0.08-4.8 years) after ILRR. All second ILRRs occurred for patients with progesterone receptor-negative ILRR. Death occurred for 7 (47 %) of 15 patients with a second ILRR and 19 (51 %) of 37 patients with a distant recurrence. As shown in the multivariable analysis, the significant predictors of survival after either a second ILRR or distant recurrence were chemotherapy for the primary cancer (hazard ratio [HR], 3.55; 95 % confidence interval [CI], 1.15-10.9; p = 0.03) and the interval (continuous) from the primary surgery (HR, 0.87; 95 % CI, 0.75-1.00; p = 0.05). CONCLUSIONS: Second ILRRs represented about one third of all recurrence events after ILRR, and all were PR-negative. These second ILRRs and distant metastases portend an unfavorable outcome.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/cirurgia , Mastectomia Segmentar/efeitos adversos , Mastectomia/efeitos adversos , Recidiva Local de Neoplasia/tratamento farmacológico , Feminino , Seguimentos , Humanos , Recidiva Local de Neoplasia/etiologia , Recidiva Local de Neoplasia/patologia , Prognóstico , Estudos Prospectivos , Taxa de Sobrevida
12.
Support Care Cancer ; 24(1): 447-455, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26335402

RESUMO

PURPOSE: Zoledronic acid (ZA) or denosumab treatment reduces skeletal-related events; however, the safety of prolonged therapy has not been adequately studied. Here, we describe safety results of extended denosumab therapy in patients with bone metastases from the open-label extension phase of two phase 3 trials. METHODS: Patients with metastatic breast or prostate cancer received subcutaneous denosumab 120 mg Q4W or intravenous ZA 4 mg Q4W in a double-blinded fashion. Denosumab demonstrated superior efficacy in the blinded treatment phase; thus, patients were offered open-label denosumab for up to an additional 2 years. RESULTS: Cumulative median (Q1, Q3) denosumab exposure was 19.1 (9.2, 32.2) months in the breast cancer trial (n = 1019) and 12.0 (5.6, 21.3) months in the prostate cancer trial (n = 942); 295 patients received denosumab for >3 years. No new safety signals were identified during the open-label phase, or among patients who switched from ZA to denosumab. During the blinded treatment phase, exposure-adjusted subject incidences of osteonecrosis of the jaw (ONJ) were 49 (1.9%) and 31 (1.2%) in the denosumab and ZA groups, respectively. In total, 32 (6.9%) and 25 (5.5 %) new cases of ONJ (not adjusted for exposure) were reported for patients continuing and switching to denosumab, respectively. The incidences of hypocalcemia were 4.3 and 3.1%, in patients continuing and switching to denosumab, respectively. CONCLUSION: These results describe the safety profile of denosumab after long-term exposure, or after switching to denosumab from ZA. No new safety signals were identified. Hypocalcemia rates were similar in the blinded treatment and open-label phases. ONJ rates increased with increasing exposure to antiresorptives, consistent with previous reports.


Assuntos
Conservadores da Densidade Óssea/administração & dosagem , Neoplasias Ósseas/tratamento farmacológico , Neoplasias da Mama , Denosumab/administração & dosagem , Neoplasias da Próstata , Administração Cutânea , Idoso , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/efeitos adversos , Conservadores da Densidade Óssea/efeitos adversos , Neoplasias Ósseas/secundário , Denosumab/efeitos adversos , Difosfonatos/administração & dosagem , Difosfonatos/efeitos adversos , Método Duplo-Cego , Esquema de Medicação , Feminino , Humanos , Imidazóis/administração & dosagem , Imidazóis/efeitos adversos , Infusões Intravenosas , Assistência de Longa Duração , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Ácido Zoledrônico
13.
Breast Cancer Res ; 17: 65, 2015 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-25935535

RESUMO

INTRODUCTION: The serine/threonine protein kinase ataxia telangiectasia mutated (ATM) is critical in maintaining genomic integrity. Upon DNA double-strand breaks, ATM phosphorylates key downstream proteins including p53 and BRCA1/2, thereby orchestrating complex signaling pathways involved in cell cycle arrest, DNA repair, senescence and apoptosis. Although sporadic mutation of ATM occurs rarely in breast cancer, the status of its protein expression and its clinical significance in breast cancer remain not well established. Our study was designed to investigate the influence of ATM protein in both tumor and cancer-associated stroma on clinical outcome in hormone-positive (HPBC) and hormone-negative (HNBC) early-stage breast cancer (EBC). METHODS: Tissue microarrays (TMAs), containing formalin-fixed, paraffin-embedded resected tumors from two cohorts of patients (HPBC cohort: n=130; HNBC cohort: n=168) diagnosed at the Tom Baker Cancer Centre, Calgary, Canada, were analyzed for ATM protein expression using fluorescence immunohistochemistry (IHC) and automated quantitative analysis (AQUA). ATM expression levels were measured within the tumor as a whole (tATM) as indicated by pan-cytokeratin expression, tumor nuclear compartment (nATM) as indicated by both DAPI and pan-cytokeratin-positive results, and cancer-associated stroma (csATM) as indicated by vimentin-positive and pan-cytokeratin-negative results. ATM expression levels within these compartments were correlated with clinical outcome. RESULTS: While tATM and nATM were significantly lower in tumors compared to normal breast epithelial tissues, csATM was significantly higher than the corresponding normal tissue compartment. In addition, the median expression level of both tATM and nATM were two- to threefold lower (P<0.001) in HNBC than in HPBC. In both HNBC and HPBC cohorts, patients with low tATM, nATM and csATM tumors had significantly poorer survival outcomes than those with a high tATM, nATM and csATM, but this effect was more pronounced in HNBC. A multivariate analysis demonstrates that these biomarkers predict survival independent of tumor size and lymph node status, but only in the HNBC cohort (P<0.001). CONCLUSIONS: Low ATM protein expression in both malignant tumor and stromal compartments likely contributes to the aggressive nature of breast cancer and is an independent prognostic factor associated with worse survival in HNBC patients.


Assuntos
Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Receptores de Estrogênio/deficiência , Receptores de Progesterona/deficiência , Células Estromais/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Proteínas Mutadas de Ataxia Telangiectasia/genética , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/mortalidade , Linhagem Celular Tumoral , Feminino , Expressão Gênica , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Avaliação de Resultados da Assistência ao Paciente , Prognóstico , Receptor ErbB-2/metabolismo , Estudos Retrospectivos , Carga Tumoral
14.
BMC Cancer ; 15: 512, 2015 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-26156521

RESUMO

BACKGROUND: Bone is the most common site of breast cancer distant metastasis, affecting 50-70 % of patients who develop metastatic disease. Despite decades of informative research, the effective prevention, prediction and treatment of these lesions remains elusive. The Breast Cancer to Bone (B2B) Metastases Research Program consists of a prospective cohort of incident breast cancer patients and four sub-projects that are investigating priority areas in breast cancer bone metastases. These include the impact of lifestyle factors and inflammation on risk of bone metastases, the gene expression features of the primary tumour, the potential role for metabolomics in early detection of bone metastatic disease and the signalling pathways that drive the metastatic lesions in the bone. METHODS/DESIGN: The B2B Research Program is enrolling a prospective cohort of 600 newly diagnosed, incident, stage I-IIIc breast cancer survivors in Alberta, Canada over a five year period. At baseline, pre-treatment/surgery blood samples are collected and detailed epidemiologic data is collected by in-person interview and self-administered questionnaires. Additional self-administered questionnaires and blood samples are completed at specified follow-up intervals (24, 48 and 72 months). Vital status is obtained prior to each follow-up through record linkages with the Alberta Cancer Registry. Recurrences are identified through medical chart abstractions. Each of the four projects applies specific methods and analyses to assess the impact of serum vitamin D and cytokine concentrations, tumour transcript and protein expression, serum metabolomic profiles and in vitro cell signalling on breast cancer bone metastases. DISCUSSION: The B2B Research Program will address key issues in breast cancer bone metastases including the association between lifestyle factors (particularly a comprehensive assessment of vitamin D status) inflammation and bone metastases, the significance or primary tumour gene expression in tissue tropism, the potential of metabolomic profiles for risk assessment and early detection and the signalling pathways controlling the metastatic tumour microenvironment. There is substantial synergy between the four projects and it is hoped that this integrated program of research will advance our understanding of key aspects of bone metastases from breast cancer to improve the prevention, prediction, detection, and treatment of these lesions.


Assuntos
Neoplasias Ósseas/metabolismo , Neoplasias Ósseas/secundário , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Neoplasias Ósseas/genética , Neoplasias da Mama/genética , Citocinas/sangue , Feminino , Perfilação da Expressão Gênica , Humanos , Estudos Prospectivos , Projetos de Pesquisa , Análise de Sobrevida , Vitamina D/sangue
15.
Lancet Oncol ; 15(2): 156-63, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24439313

RESUMO

BACKGROUND: Patients with isolated locoregional recurrences (ILRR) of breast cancer have a high risk of distant metastasis and death from breast cancer. We aimed to establish whether adjuvant chemotherapy improves the outcome of such patients. METHODS: The CALOR trial was a pragmatic, open-label, randomised trial that accrued patients with histologically proven and completely excised ILRR after unilateral breast cancer who had undergone a mastectomy or lumpectomy with clear surgical margins. Eligible patients were enrolled from hospitals worldwide and were centrally randomised (1:1) to chemotherapy (type selected by the investigator; multidrug for at least four courses recommended) or no chemotherapy, using permuted blocks, and stratified by previous chemotherapy, oestrogen-receptor and progesterone-receptor status, and location of ILRR. Patients with oestrogen-receptor-positive ILRR received adjuvant endocrine therapy, radiation therapy was mandated for patients with microscopically involved surgical margins, and anti-HER2 therapy was optional. The primary endpoint was disease-free survival. All analyses were by intention to treat. This study is registered with ClinicalTrials.gov, number NCT00074152. FINDINGS: From Aug 22, 2003, to Jan 31, 2010, 85 patients were randomly assigned to receive chemotherapy and 77 were assigned to no chemotherapy. At a median follow-up of 4·9 years (IQR 3·6-6 ·0), 24 (28%) patients had disease-free survival events in the chemotherapy group compared with 34 (44%) in the no chemotherapy group. 5-year disease-free survival was 69% (95% CI 56-79) with chemotherapy versus 57% (44-67) without chemotherapy (hazard ratio 0·59 [95% CI 0·35-0·99]; p=0·046). Adjuvant chemotherapy was significantly more effective for women with oestrogen-receptor-negative ILRR (pinteraction=0·046), but analyses of disease-free survival according to the oestrogen-receptor status of the primary tumour were not statistically significant (pinteraction=0·43). Of the 81 patients who received chemotherapy, 12 (15%) had serious adverse events. The most common adverse events were neutropenia, febrile neutropenia, and intestinal infection. INTERPRETATION: Adjuvant chemotherapy should be recommended for patients with completely resected ILRR of breast cancer, especially if the recurrence is oestrogen-receptor negative. FUNDING: US Department of Health and Human Services, Swiss Group for Clinical Cancer Research (SAKK), Frontier Science and Technology Research Foundation, Australian and New Zealand Breast Cancer Trials Group, Swedish Cancer Society, Oncosuisse, Cancer Association of South Africa, Foundation for Clinical Research of Eastern Switzerland (OSKK), Grupo Español de Investigación en Cáncer de Mama (GEICAM), and the Dutch Breast Cancer Trialists' Group (BOOG).


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Austrália , Biomarcadores Tumorais/análise , Neoplasias da Mama/química , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Quimioterapia Adjuvante , Progressão da Doença , Intervalo Livre de Doença , Europa (Continente) , Feminino , Humanos , Análise de Intenção de Tratamento , Estimativa de Kaplan-Meier , Mastectomia , Mastectomia Segmentar , Recidiva Local de Neoplasia/química , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/cirurgia , América do Norte , Seleção de Pacientes , Modelos de Riscos Proporcionais , Radioterapia Adjuvante , Fatores de Risco , África do Sul , América do Sul , Taxa de Sobrevida , Fatores de Tempo , Resultado do Tratamento
16.
J Magn Reson ; 365: 107726, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38991267

RESUMO

Improving the spectral sensitivity and resolution of biological solids is one of the long-standing problems in nuclear magnetic resonance (NMR) spectroscopy. In this report, we introduce low-power supercycled variants of two-pulse phase-modulated (TPPM) sequence for heteronuclear decoupling. The utility of the sequence is shown by improvements in the transverse relaxation time of observed nuclei (with 1H decoupling) with its application to different samples (uniformly 13C, 15N, 2H-labeled GB1 back-exchanged with 25% H2O and 75% D2O, uniformly 13C, 15N, 2H-labeled human derived Asyn fibril back-exchanged with 100% H2O and uniformly 13C, 15N -labeled human derived Asyn fibril) at fast MAS using low radiofrequency (RF) fields. To understand the effect of spinning speed, the transverse relaxation time is monitored under different spinning frequencies. In comparison to existing heteronuclear decoupling sequences, the supercycled TPPM (sTPPM) sequence significantly improves the spectral sensitivity and resolution and is robust towards B1 inhomogeneity and decoupler offset.

17.
J Magn Reson ; 367: 107747, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39178749

RESUMO

The development of magic angle spinning (MAS) at rates ranging from 30 kHz to greater than 100 kHz has substantially advanced solid-state nuclear magnetic resonance (SSNMR) spectroscopy 1H-detection methods. The small rotors required for such MAS rates have a limited sample volume and low 13C-detection sensitivity, rendering the traditional set of standard compounds for SSNMR insufficient or highly inconvenient for shimming and magic-angle calibration. Additionally, the reproducibility of magic angle setting, chemical shift referencing, and probe position can be especially critical for SSNMR experiments at high fields. These conditions suggest the need for a high signal-to-noise ratio (SNR) 1H-detection standard compound, which is preferably multi-purpose, to simplify instrument set up for ultra-fast MAS SSNMR instruments at high magnetic fields. In this study, we present the results for setting magic angle and shimming using tetrakis(trimethylsilyl)silane (TTMSS, or TKS), a tetramethylsilane (TMS) analogue, at near 40 kHz and demonstrate that we can achieve favorable results in less time but with equal or superior precision as traditional KBr and adamantane standards. The high SNR and TMS-like chemical shift of TKS also opens the possibilities for using TKS as an internal standard with biological samples. A single rotor containing a four-component mixture of TKS, adamantane, uniformly 13C, 15N-labeled N-acetyl valine and KBr was used to perform a complete configuration and calibration of a SSNMR probe without sample changes. We anticipate TKS as a standard compound to be especially effective at very high MAS conditions and to greatly simplify the instrument set up for high and ultra-high field SSNMR instruments.

18.
Invest New Drugs ; 31(3): 696-706, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22886613

RESUMO

PURPOSE: This open-labeled, phase I clinical trial was designed to determine the safety and tolerability of percutaneous intralesional administration of wild-type oncolytic revovirus type 3 Dearing (Reolysin®) in cancer patients with accessible and evaluable disease, who had otherwise failed to improve on standard cancer interventions. EXPERIMENTAL DESIGN: An escalating dose of Reolysin® starting from up to 10(10) plague forming units (PFU) was administered to each cohort of three patients per dose level. Viral shedding, reovirus neutralizing antibody response, toxicity and clinical response were assessed. RESULTS: Nineteen patients with various advanced solid tumors were treated. The most common toxicities related to treatment were grade 2 (or less) local erythema and transient flu like symptoms. Viral shedding was not seen in cerebral spinal fluid (CSF), urine and stool samples in all patients. Rising viral antibody titres were seen in all patients. In addition, we observed some evidence of local target tumor response activity in 7/19 patients (37 %) at the end of six or more weeks follow-up, with one patient exhibiting a complete response (CR), two a partial response (PR), and four stable disease (SD) to the local injected lesion. CONCLUSIONS: Reolysin® is well tolerated given intralesionaly, with DLT/MTD not reached at a dose of 10(10) PFU. The favorable toxicity profile, lack of viral shedding and possible therapeutic activity has made this unattenuated oncolytic reovirus an attractive cancer therapeutic agent for ongoing clinical studies, including in the setting of locally advanced accessible disease for palliation of symptoms.


Assuntos
Antineoplásicos/administração & dosagem , Orthoreovirus Mamífero 3 , Neoplasias/terapia , Terapia Viral Oncolítica , Vírus Oncolíticos , Administração Cutânea , Adulto , Idoso , Anticorpos Antivirais/sangue , Antineoplásicos/efeitos adversos , Feminino , Cefaleia/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Náusea/etiologia , Neoplasias/sangue , Neoplasias/virologia , Terapia Viral Oncolítica/efeitos adversos , Eliminação de Partículas Virais , Vômito/etiologia
19.
Lancet Oncol ; 13(7): 734-42, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22704583

RESUMO

BACKGROUND: Bisphosphonates are thought to act through the osteoclast by changing bone microenvironment. Previous findings of adjuvant clodronate trials in different populations with operable breast cancer have been mixed. The National Surgical Adjuvant Breast and Bowel Project (NSABP) protocol B-34 aims to ascertain whether oral clodronate can improve outcomes in women with primary breast cancer. METHODS: NSABP B-34 is a multicentre, randomised, double-blind, placebo-controlled study in 3323 women with stage 1-3 breast cancer. After surgery to remove the tumour, patients were stratified by age, axillary nodes, and oestrogen and progesterone receptor status and randomly assigned in a 1:1 ratio to either oral clodronate 1600 mg daily for 3 years (n=1662) or placebo (1661). The primary endpoint was disease-free survival, analysed by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT00009945. FINDINGS: Median follow-up was 90·7 months (IQR 82·7-100·0) and 3311 patients had data for this period. Disease-free survival did not differ between groups (286 events in the clodronate group vs 312 in the placebo group; hazard ratio 0·91, 95% CI 0·78-1·07; p=0·27). Moreover, no differences were recorded for overall survival (0·84, 0·67-1·05; p=0·13), recurrence-free interval (0·83, 0·67-1·04; p=0·10), or bone metastasis-free interval (0·77, 0·55-1·07; p=0·12). Non-bone metastasis-free interval was slightly increased with clodronate (0·74, 0·55-1·00; p=0·047). Analyses in women age 50 years or older on study entry showed benefits of clodronate for recurrence-free interval (0·75, 0·57-0·99; p=0·045), bone metastasis-free interval (0·62, 0·40-0·95; p=0·027), and non-bone metastasis-free interval (0·63, 0·43-0·91; p=0·014), but not for overall survival (0·80, 0·61-1·04, p=0·094). Adherence to treatment at 3 years was 56% for the clodronate group and 60% for the placebo group. Grade 3 or higher liver dysfunction was noted in 23 of 1612 patients in the clodronate group and 12 of 1623 patients in the placebo group; grade 3-4 diarrhoea was noted in 28 patients in the clodronate group and in ten in the placebo group. There was one possible case of osteonecrosis of the jaw in the clodronate group. INTERPRETATION: Findings of NSABP B-34 suggest that bisphosphonates might have anticancer benefits for older postmenopausal women. A meta-analysis of adjuvant bisphosphonate trials is suggested before recommendations for use in non-osteoporotic postmenopausal women with primary breast cancer are made. FUNDING: National Cancer Institute, Bayer Oy (formerly Schering Oy).


Assuntos
Conservadores da Densidade Óssea/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Ácido Clodrônico/uso terapêutico , Administração Oral , Adulto , Fatores Etários , Idoso , Neoplasias da Mama/mortalidade , Ácido Clodrônico/efeitos adversos , Intervalo Livre de Doença , Método Duplo-Cego , Feminino , Humanos , Pessoa de Meia-Idade
20.
JCO Clin Cancer Inform ; 7: e2300116, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38011617

RESUMO

PURPOSE: There is strong interest from patients, researchers, the pharmaceutical industry, medical journal editors, funders of research, and regulators in sharing clinical trial data for secondary analysis. However, data access remains a challenge because of concerns about patient privacy. It has been argued that synthetic data generation (SDG) is an effective way to address these privacy concerns. There is a dearth of evidence supporting this on oncology clinical trial data sets, and on the utility of privacy-preserving synthetic data. The objective of the proposed study is to validate the utility and privacy risks of synthetic clinical trial data sets across multiple SDG techniques. METHODS: We synthesized data sets from eight breast cancer clinical trial data sets using three types of generative models: sequential synthesis, conditional generative adversarial network, and variational autoencoder. Synthetic data utility was evaluated by replicating the published analyses on the synthetic data and assessing concordance of effect estimates and CIs between real and synthetic data. Privacy was evaluated by measuring attribution disclosure risk and membership disclosure risk. RESULTS: Utility was highest using the sequential synthesis method where all results were replicable and the CI overlap most similar or higher for seven of eight data sets. Both types of privacy risks were low across all three types of generative models. DISCUSSION: Synthetic data using sequential synthesis methods can act as a proxy for real clinical trial data sets, and simultaneously have low privacy risks. This type of generative model can be one way to enable broader sharing of clinical trial data.


Assuntos
Neoplasias da Mama , Privacidade , Humanos , Feminino , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/terapia , Oncologia , Pesquisadores
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