RESUMO
PURPOSE: Despite previous studies proposing shorter durations of anti-HER2 therapy for selected patients with HER2-positive early breast cancer (EBC), 12-months remains standard of care. A survey was performed to assess patient perspectives and willingness to participate in studies evaluating shorter durations of anti-HER2 therapy. METHODS: Patients with HER2-positive EBC completing or having previously completed anti-HER2 therapy, were recruited by healthcare professionals at The Ottawa Hospital Cancer Centre to participate in an anonymous online survey. The primary objective was to learn about patients' perspectives on shorter durations (less than 12-months) of anti-HER2 therapy. Secondary objectives were to explore patients' interest in clinical trials of shorter durations of anti-HER2 therapy and the degree of increased breast cancer risk they would accept with a shorter treatment duration. RESULTS: Responses were received from 94 eligible patients. Most patients received Trastuzumab alone (78%, 73/94), while 13% (12/94) received trastuzumab and pertuzumab. Side effects were experienced by 52% (46/89), the most common being; fatigue (61%, 28/46), myalgia (37%, 17/46), and diarrhea (24%, 11/46). Most patients (88%, 78/89) did not find treatment bothersome. Regarding perspectives on shorter durations of anti-HER2 therapy, most (79%, 74/94) respondents stated they would agree to less treatment if it were possible to receive fewer treatments with the same cancer benefits. 56% of patients were interested in clinical trials, however, about half stated they would not be accepting of any increase in breast cancer recurrence risk. CONCLUSION: Trials to investigate who can safely and effectively be treated with shorter durations of anti-HER2 therapy are needed. This study provides important insights to patients' perspectives on shorter durations of anti-HER2 treatment, and their concerns regarding potential increased cancer risk with less treatment.
Assuntos
Neoplasias da Mama , Receptor ErbB-2 , Humanos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Feminino , Receptor ErbB-2/metabolismo , Pessoa de Meia-Idade , Idoso , Adulto , Inquéritos e Questionários , Trastuzumab/uso terapêutico , Estadiamento de Neoplasias , Anticorpos Monoclonais Humanizados/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Idoso de 80 Anos ou maisRESUMO
BACKGROUND: The use of Escherichia coli purine nucleoside phosphorylase (PNP) to activate fludarabine has demonstrated safety and antitumor activity during preclinical analysis and has been approved for clinical investigation. PATIENTS AND METHODS: A first-in-human phase I clinical trial (NCT 01310179; IND 14271) was initiated to evaluate safety and efficacy of an intratumoral injection of adenoviral vector expressing E. coli PNP in combination with intravenous fludarabine for the treatment of solid tumors. The study was designed with escalating doses of fludarabine in the first three cohorts (15, 45, and 75 mg/m(2)) and escalating virus in the fourth (10(11)-10(12) viral particles, VP). RESULTS: All 12 study subjects completed therapy without dose-limiting toxicity. Tumor size change from baseline to final measurement demonstrated a dose-dependent response, with 5 of 6 patients in cohorts 3 and 4 achieving significant tumor regression compared with 0 responsive subjects in cohorts 1 and 2. The overall adverse event rate was not dose-dependent. Most common adverse events included pain at the viral injection site (92%), drainage/itching/burning (50%), fatigue (50%), and fever/chills/influenza-like symptoms (42%). Analysis of serum confirmed the lack of systemic exposure to fluoroadenine. Antibody response to adenovirus was detected in two patients, suggesting that neutralizing immune response is not a barrier to efficacy. CONCLUSIONS: This first-in-human clinical trial found that localized generation of fluoroadenine within tumor tissues using E. coli PNP and fludarabine is safe and effective. The pronounced effect on tumor volume after a single treatment cycle suggests that phase II studies are warranted. CLINICALTRIALSGOV IDENTIFIER: NCT01310179.
Assuntos
Escherichia coli/enzimologia , Terapia Genética , Vetores Genéticos/uso terapêutico , Neoplasias/genética , Neoplasias/terapia , Purina-Núcleosídeo Fosforilase/administração & dosagem , Vidarabina/análogos & derivados , Adenoviridae/genética , Idoso , Idoso de 80 Anos ou mais , Terapia Combinada , Relação Dose-Resposta a Droga , Feminino , Seguimentos , Humanos , Injeções Intralesionais , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias/patologia , Prognóstico , Purina-Núcleosídeo Fosforilase/genética , Células Tumorais Cultivadas , Vidarabina/uso terapêuticoRESUMO
OBJECTIVE: This study set out to determine if cetuximab treatment increases the risk of wound healing complications when combined with radiation therapy. METHOD: We performed a retrospective chart review of head and neck cancer patients who received salvage neck dissections between 1999 and 2007, at two academic tertiary care centres. Complications from wound healing were compared between radiation and combined therapy groups. RESULTS: A total of 35 patients received radiation (n=20) or combined radiation and cetuximab therapy (n=15) prior to neck dissection. The treatment groups were similar in regard to demographic and primary tumour-related characteristics. The time between treatment and salvage neck dissection did not differ between the radiation (3.9 months) and combination treatment (3.0 months) groups (p=0.15). Wound healing complications occurred in 13% (2/15) of the patients treated with radiation and cetuximab and there were no complications in patients who received radiation alone (p=0.20). CONCLUSION: Cetuximab did not significantly increase the risk of post-surgical wound complications, although a higher absolute number of wound complications was observed in the group treated with cetuximab and radiation therapy, compared with the group treated with radiation alone. CONFLICT OF INTEREST: This work was supported by a grant from the National Institute of Health (2T32 CA091078-06). One of the authors, JAB, is an occasional consultant and honoraria for ImClone and Bristol-Meyers Squibb.
Assuntos
Fator de Crescimento Epidérmico/uso terapêutico , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/radioterapia , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados , Cetuximab , Terapia Combinada , Humanos , Estudos Retrospectivos , CicatrizaçãoRESUMO
The performances of nine commercially available capillary zone electrophoresis (CZE) capillaries were tested and compared. Five model polypeptides, ranging in size from a tetrapeptide (604 D) to beta-lactamase 1 (approximately 29,000 D), were run at 32 degrees C on each of the nine capillaries using 10-mM ionic strength buffers at pH 3.5, 5.0, and 6.5. These results were then used to evaluate each capillary's performance. Factors used to assess the performance included comparison of observed electrophoretic mobilities (mu) to predicted mu (Overbeek-Wiersema model, O-W model; see appendix); reproducibility and consistency of the electroosmotic (EO) flow marker or internal marker throughout testing; and peak shape, height, and signal-to-noise. Five of the nine capillaries were evaluated further for migration time (MT) reproducibility over 50 injections of a polypeptide. A direct correlation was observed between peak tailing and slower observed mu. Those capillaries that exhibited a greater amount of tailing also had observed mu that were slower than predicted by the O-W model. As expected for any model, other capillaries produced observed mu that were faster than those predicted.
Assuntos
Eletroforese Capilar/métodos , Peptídeos/isolamento & purificação , Concentração de Íons de HidrogênioRESUMO
The trp repressor of Escherichia coli specifically binds to operator DNAs in three operons involved in tryptophan metabolism. The NMR spectra of repressor and a chymotryptic fragment lacking the six amino-terminal residues are compared. Two-dimensional J-correlated spectra of the two forms of the protein are superimposable except for cross-peaks that are associated with the N-terminal region. The chemical shifts and relaxation behavior of the N-terminal resonances suggest mobile "arms". Spin-echo experiments on a ternary complex of repressor with L-tryptophan and operator DNA indicate that the termini are also disordered in the complex, although removal of the arms reduces the DNA binding energy. Relaxation measurements on the armless protein show increased mobility for several residues, probably due to helix fraying in the newly exposed N-terminal region. DNA binding by the armless protein does not reduce the mobility of these residues. Thus, it appears that the arms serve to stabilize the N-terminal helix but that this structural role does not explain their contribution to the DNA binding energy. These results suggest that the promiscuous DNA binding by the arms seen in the X-ray crystal structure is found in solution as well.
Assuntos
Proteínas de Bactérias , Escherichia coli/metabolismo , Óperon , Proteínas Repressoras/metabolismo , Fatores de Transcrição/metabolismo , Quimotripsina , DNA Bacteriano/metabolismo , Escherichia coli/genética , Espectroscopia de Ressonância Magnética/métodos , Fragmentos de Peptídeos/isolamento & purificação , Conformação ProteicaRESUMO
The regulatory effects of allelic substitution at the trans-acting mapP locus and of dietary glucose on the expression of the duplicate genes for alpha-amylase (Amy) in Drosophila melanogaster were examined in the anterior midgut and posterior midgut regions of mature flies. The levels of amylase activity and amylase protein, as well as the abundance of amylase-specific RNA, were quantified. All 3 parameters of Amy expression were concordant. Results indicate that the effects of both mapP and dietary glucose are exerted at the level of amylase RNA. However, the tissue-specific effects of mapP are restricted to the posterior midgut and can therefore be distinguished from the effects of glucose in food medium, which influences amylase RNA levels in both the anterior and posterior midgut regions. Our data suggest that, in large part, strain-specific effects of dietary glucose can be explained on the basis of alternate alleles at the mapP locus in different homozygous strains of flies. Levels of amylase RNA in tissue extracts of flies from an amylase-null strain were also measured. Low levels were observed in both anterior and posterior midgut extracts. These were unresponsive to dietary conditions.
Assuntos
Dieta , Drosophila melanogaster/enzimologia , Regulação Enzimológica da Expressão Gênica , alfa-Amilases/genética , Animais , Sistema Digestório/metabolismo , Drosophila melanogaster/genética , Feminino , Genes Reguladores , Glucose/fisiologia , Imunoeletroforese , Masculino , Fenótipo , RNA/metabolismoRESUMO
We examined colonial phenotypes of five isolates of Blastomyces dermatitidis at 33, 35 and 37 degrees C on four growth media. Three different colony types were identified: yeast, mycelial, and a mixed type consisting of both yeast and mycelia. Each isolate varied in its ability to grow on the different media and at different temperatures, and in the types of colonies it produced in the various temperature-media combinations. Quantification of the number of nuclei per yeast cell by fluorescent staining revealed no correlation between the number of nuclei per cell and the colonial phenotype. These results indicate that the colonial phenotype of B. dermatitidis varies with the isolate as well as with temperature and culture medium, but is not correlated with the number of nuclei per yeast. These findings could provide a start towards typing B. dermatitidis isolates.
Assuntos
Blastomyces/citologia , Blastomyces/genética , Blastomyces/crescimento & desenvolvimento , Núcleo Celular/ultraestrutura , Contagem de Colônia Microbiana , Meios de Cultura , Fenótipo , Coloração e Rotulagem , TemperaturaRESUMO
The resonances in the aromatic region of the 1H-NMR spectrum of the Escherichia coli trp aporepressor have been assigned to amino acid type by two-dimensional correlated spectroscopy (COSY), homonuclear Hartmann-Hahn (HOHAHA) spectroscopy and nuclear Overhauser enhancement spectroscopy (NOESY) techniques and studies of the pH dependence of the chemical shifts, in combination with selective deuteration of the protein. Complete sequence-specific assignments of the aromatic resonances have been made by comparing the observed inter-residue NOEs with those expected on the basis of the crystal structure of the protein [Zhang, R.-G., Joachimiak, A., Lawson, C.L., Shevitz, R.W., Otwinowski, Z. & Sigler, P.B. (1987) Nature 327, 591-597]. The latter experiments have also permitted the sequence-specific assignment of some of the high-field methyl resonances. The complete assignment of the aromatic region of the spectrum, in particular of resonances from residues at the dimer interface, opens the way to detailed studies of the conformational effects of corepressor and operator binding.