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3.
South Med J ; 113(11): 559-563, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33140109

RESUMO

OBJECTIVES: Preoperative chemotherapy produces tumor shrinkage in most patients with locally advanced breast cancer, including some pathological complete responses (pCRs). We attempted this using a much less toxic sequential regimen, given with concurrent bevacizumab. METHODS: Patients with locally advanced breast cancer received 3 intravenous doses each of preoperative sequential liposome encapsulated doxorubicin 25 mg/m2, paclitaxel 175 mg/m2, and cyclophosphamide 600 mg/m2, with concurrent bevacizumab every 2 weeks without growth factor support. RESULTS: Between March 2008 and December 2009, 32 patients received treatment. There was no cardiotoxicity, and other toxicity was mild (no grade 4 or 5 toxicity). No long-term toxicity, including cardiotoxicity, has been observed. Every patient had ≥30% reduction in tumor size; 9 of 31 patients who completed chemotherapy had pCR at operation. Seven years later, 22 of 32 patients remain free of recurrence and 27 of 32 are alive. CONCLUSIONS: The preoperative chemotherapy used appears to be comparably effective, but much less toxic than that used in most conventional regimens and should be studied further. Concurrent treatment with bevacizumab (reported separately) did not provide any additional benefit.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Adulto , Idoso , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Bevacizumab/administração & dosagem , Bevacizumab/efeitos adversos , Bevacizumab/uso terapêutico , Neoplasias da Mama/patologia , Neoplasias da Mama/terapia , Terapia Combinada/efeitos adversos , Ciclofosfamida/administração & dosagem , Ciclofosfamida/efeitos adversos , Ciclofosfamida/uso terapêutico , Doxorrubicina/administração & dosagem , Doxorrubicina/efeitos adversos , Doxorrubicina/uso terapêutico , Feminino , Humanos , Pessoa de Meia-Idade , Paclitaxel/administração & dosagem , Paclitaxel/efeitos adversos , Paclitaxel/uso terapêutico , Projetos Piloto
5.
Ann Surg ; 270(1): 69-76, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30649014

RESUMO

OBJECTIVE: This review details the agents for fluorescence-guided nerve imaging in both preclinical and clinical use to identify factors important in selecting nerve-specific fluorescent agents for surgical procedures. BACKGROUND: Iatrogenic nerve injury remains a significant cause of morbidity in patients undergoing surgical procedures. Current real-time identification of nerves during surgery involves neurophysiologic nerve stimulation, which has practical limitations. Intraoperative fluorescence-guided imaging provides a complimentary means of differentiating tissue types and pathology. Recent advances in fluorescence-guided nerve imaging have shown promise, but the ideal agent remains elusive. METHODS: In February 2018, PubMed was searched for articles investigating peripheral nerve fluorescence. Key terms used in this search include: "intraoperative, nerve, fluorescence, peripheral nerve, visualization, near infrared, and myelin." Limits were set to exclude articles exclusively dealing with central nervous system targets or written in languages other than English. References were cross-checked for articles not otherwise identified. RESULTS: Of the nonspecific agents, tracers that rely on axonal transport showed the greatest tissue specificity; however, neurovascular dyes already enjoy wide clinical use. Fluorophores specific to nerve moieties result in excellent nerve to background ratios. Although noteworthy findings on tissue specificity, toxicity, and route of administration specific to each fluorescent agent were reported, significant data objectively quantifying nerve-specific fluorescence and toxicity are lacking. CONCLUSIONS: Fluorescence-based nerve enhancement has advanced rapidly over the past 10 years with potential for continued utilization and progression in translational research. An ideal agent would be easily administered perioperatively, would not cross the blood-brain barrier, and would fluoresce in the near-infrared spectrum. Agents administered systemically that target nerve-specific moieties have shown the greatest promise. Based on the heterogeneity of published studies and methods for reporting outcomes, it appears that the development of an optimal nerve imaging agent remains challenging.


Assuntos
Cuidados Intraoperatórios/métodos , Imagem Óptica/métodos , Nervos Periféricos/diagnóstico por imagem , Meios de Contraste , Corantes Fluorescentes , Humanos , Especificidade de Órgãos , Sensibilidade e Especificidade
6.
J Surg Res ; 231: 36-42, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30278953

RESUMO

BACKGROUND: Mastectomy remains an effective treatment for ductal carcinoma in situ (DCIS) but whether further therapy is warranted for close or positive margins is controversial. We aim to characterize the treatment practices of DCIS throughout the United States in patients who undergo mastectomy with close or positive margins to better understand the use of postmastectomy radiation therapy (PMRT). MATERIALS AND METHODS: Using the 2004-2013 National Cancer Database, we identified all female patients with a diagnosis of DCIS who underwent mastectomy. Distributional characteristics were summarized for overall and margin-stratified samples. Characteristic differences were assessed by region and receipt of radiation. Chi-square and independent sample t-tests were used to assess differences for categorical and continuous variables, respectively. RESULTS: In 21,591 patients who met inclusion criteria, 470 patients with close/positive margins were identified. Sixteen percent of patients with close/positive margins received PMRT compared to 1.5% with negative margins (P < 0.01). There was no difference in PMRT and patient race, insurance status, treatment facility, or endocrine therapy. Patients with close/positive margins who received PMRT were more likely to be in an urban setting from the Midwest (24.6%) and Northeast (21.8%) compared to the West (11.0%) and South (10.7%) (P < 0.01). CONCLUSIONS: Use of PMRT for DCIS following mastectomy with close/positive margins differs across the country. Regional variations in treatment patterns reinforce a need to determine whether PMRT improves survival to establish treatment guidelines.


Assuntos
Neoplasias da Mama/radioterapia , Carcinoma Intraductal não Infiltrante/radioterapia , Margens de Excisão , Adulto , Idoso , Neoplasias da Mama/cirurgia , Carcinoma Intraductal não Infiltrante/cirurgia , Feminino , Humanos , Mastectomia , Pessoa de Meia-Idade , Estudos Retrospectivos
8.
Curr Top Med Chem ; 17(6): 676-695, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27320329

RESUMO

This review focuses on our efforts to translate a low-toxicity retinoid X receptor-selective agonist, UAB30, to the clinic for the prevention of breast cancers. The review is divided into several sections. First, the current status of breast cancer prevention is discussed. Next, preclinical studies are presented that support translation of rexinoids to the clinic for cancer prevention. While current FDAapproved retinoids and rexinoids demonstrate profound effects in treating cancers, they lack sufficient safety for long term use in the high risk population that is otherwise disease free. The review stresses the need to identify cancer preventive drugs that are effective and safe in order to gain wide use in the clinic. Due to the heterogeneity of the disease, UAB30 is evaluated for the prevention of ER-positive and ER-negative mammary cancers. Since selective estrogen receptor modulators and aromatase inhibitors are used clinically to prevent and treat ER-positive breast cancers, preclinical studies also must demonstrate efficacy of UAB30 in combination with existing drugs under use in the clinic. To support an Investigational New Drug Application to the FDA, data on pharmacology and toxicity as well as mutagenicity is gathered prior to human trials. The review concludes with a discussion of the outcomes of human Phase 0/1 clinical trials that determine the safety and pharmacology of UAB30. These studies are essential before this agent is evaluated for efficacy in phase 2 trials. Success in phase 2 evaluation is critical before long-term and costly phase 3 trials are undertaken. The lack of surrogate biomarkers as endpoints for phase 2 evaluation of rexinoid preventive agents is discussed.


Assuntos
Neoplasias da Mama/prevenção & controle , Ácidos Graxos Insaturados/administração & dosagem , Naftalenos/administração & dosagem , Dimerização , Feminino , Humanos , Hipertrigliceridemia/metabolismo , Gravidez , Transdução de Sinais
9.
Oncotarget ; 7(49): 80655-80663, 2016 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-27811364

RESUMO

E-cadherin (CDH1) is a glycoprotein that mediates adhesion between epithelial cells and also suppresses cancer invasion. Mutation or deletion of the CDH1 gene has been reported in 30-60% cases of invasive lobular carcinoma (ILC). However, little is known about genomic differences between ILC with and without a CDH1 alteration. Therefore, we analyzed whole genome sequencing data of 169 ILC cases from The Cancer Genome Atlas (TCGA) to address this deficiency. Our study shows that CDH1 gene was altered in 59.2% (100/169) of ILC. No significant difference was identified between CDH1-altered and -unaltered ILC cases for any of the examined demographic, clinical or pathologic characteristics, including histologic grade, tumor stage, lymph node metastases, or ER/PR/HER2 states. Seven recurrent mutations (PTEN, MUC16, ERBB2, FAT4, PCDHGA2, HERC1 and FLNC) and four chromosomal changes with recurrent copy number variation (CNV) (11q13, 17q12-21, 8p11 and 8q11) were found in ILC, which correlated with a positive or negative CDH1 alteration status, respectively. The prevalence of the most common breast cancer driver abnormalities including TP53 and PIK3CA mutations and MYC and ERBB2 amplifications showed no difference between the two groups. However, CDH1-altered ILC with an ERBB2 mutation shows a significantly worse prognosis compared to its counterparts without such a mutation. Our study suggests that CDH1-altered ILC patients with ERBB2 mutations may represent an actionable group of patients who could benefit from targeted breast cancer therapy.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Caderinas/genética , Carcinoma Ductal de Mama/genética , Carcinoma Lobular/genética , Mutação , Receptor ErbB-2/genética , Antígenos CD , Neoplasias da Mama/enzimologia , Neoplasias da Mama/patologia , Neoplasias da Mama/terapia , Carcinoma Ductal de Mama/enzimologia , Carcinoma Ductal de Mama/patologia , Carcinoma Ductal de Mama/terapia , Carcinoma Lobular/enzimologia , Carcinoma Lobular/patologia , Carcinoma Lobular/terapia , Biologia Computacional , Análise Mutacional de DNA , Bases de Dados Genéticas , Intervalo Livre de Doença , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Invasividade Neoplásica , Fenótipo , Medicina de Precisão , Fatores de Risco , Análise de Sobrevida , Fatores de Tempo
10.
JAMA Surg ; 151(8): 768-70, 2016 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-27096328

RESUMO

This Special Communication summarizes the key points raised at the Society of Surgical Chairs mentorship panel sessions held at the 2014 and 2015 annual meetings of the society. Highlights of these expert panel discussions include senior chairs' insights into successfully dealing with increasingly complex academic medical organizations and horizontal department management expectations in the context of the arrival of the Millennial Generation into the work force. Three key tenets of effective surgery leadership that arose from these sessions deal with the importance of (1) collaboration and cooperativity, (2) humanized relationships and mentorship, and (3) operational efficiency. Overall, the panel consensus for the future of surgery leadership was optimistic while recognizing that the demands of chairmanship are considerable.


Assuntos
Comportamento Cooperativo , Eficiência , Cirurgia Geral/organização & administração , Relações Interpessoais , Liderança , Congressos como Assunto , Humanos , Mentores
11.
J Med Chem ; 58(19): 7763-74, 2015 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-26331194

RESUMO

(2E,4E,6Z,8Z)-8-(3',4'-Dihydro-1'(2H)-naphthalen-1'-ylidene)-3,7-dimethyl-2,3,6-octatrienoinic acid (UAB30) is currently undergoing clinical evaluation as a novel cancer prevention agent. In efforts to develop even more highly potent rexinoids that prevent breast cancer without toxicity, we further explore here the structure-activity relationship of two separate classes of rexinoids. UAB30 belongs to the class II rexinoids and possesses a 9Z-tetraenoic acid chain bonded to a tetralone ring, whereas the class I rexinoids contain the same 9Z-tetraenoic acid chain bonded to a disubstituted cyclohexenyl ring. Among the 12 class I and class II rexinoids evaluated, the class I rexinoid 11 is most effective in preventing breast cancers in an in vivo rat model alone or in combination with tamoxifen. Rexinoid 11 also reduces the size of established tumors and exhibits a therapeutic effect. However, 11 induces hypertriglyceridemia at its effective dose. On the other hand rexinoid 10 does not increase triglyceride levels while being effective in the in vivo chemoprevention assay. X-ray studies of four rexinoids bound to the ligand binding domain of the retinoid X receptor reveal key structural aspects that enhance potency as well as those that enhance the synthesis of lipids.


Assuntos
Anticarcinógenos/química , Anticarcinógenos/farmacologia , Ácidos Graxos Insaturados/química , Neoplasias Mamárias Experimentais/prevenção & controle , Naftalenos/química , Relação Estrutura-Atividade , Animais , Anticarcinógenos/efeitos adversos , Anticarcinógenos/metabolismo , Sítios de Ligação , Técnicas de Química Sintética , Cristalografia por Raios X , Dislipidemias/induzido quimicamente , Dislipidemias/metabolismo , Feminino , Humanos , Neoplasias Mamárias Experimentais/induzido quimicamente , Conformação Molecular , Ratos Sprague-Dawley , Receptor X Retinoide alfa/química , Receptor X Retinoide alfa/metabolismo , Tamoxifeno/farmacologia , Triglicerídeos/sangue
12.
Shock ; 44(1): 3-15, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26070000

RESUMO

As with sharks and horseshoe crabs, some designs of nature need only minor evolutionary adjustments during the millennia to remain superbly adapted. Such is the case at the molecular level for the nuclear receptors (NRs), which seem to have originated concomitantly with the earliest metazoan lineage of animals. A wide array of NRs persists today throughout all animal phyla with many different functions, yet they share a highly conserved protein structure, a testament to their having evolved through numerous gene duplications. Of particular interest for this readership are the estrogen-related receptors (ERRs), which have significant supportive roles in energy creation and regulation, mitochondrial function and biogenesis, development, tissue repair, hypoxia, and cancer. Thus, placed at the nexus of energetics and homeostasis, ERR (in association with the coregulatory molecules peroxisome proliferator-activated receptor-γ coactivator-1α and -ß) can facilitate repair from injury and adaptations to stressful environments. Whereas it is curious that ERRs and some other NRs exist as "orphans" by virtue of having no known cognate ligand, increasing interest in the estrogen receptor has led to the development of synthetic ligands and screening for naturally occurring molecules, either capable of modulating ERR activity. Thus, what is needed now is a nomenclature update for the ERR to focus the mind on energetics and metabolism, the most compromised and crucial systems after trauma and shock.


Assuntos
Metabolismo Energético , Evolução Molecular , Mitocôndrias , Receptores de Estrogênio , Choque , Ferimentos e Lesões , Animais , Humanos , Mitocôndrias/genética , Mitocôndrias/metabolismo , PPAR gama/genética , PPAR gama/metabolismo , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo , Choque/genética , Choque/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Ferimentos e Lesões/genética , Ferimentos e Lesões/metabolismo
13.
J Minim Invasive Gynecol ; 22(5): 799-806, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25796218

RESUMO

OBJECTIVES: Ureter injury is a serious complication of laparoscopic surgery. Current strategies to identify the ureters, such as placement of a ureteral stent, carry additional risks for patients. We hypothesize that the systemically injected near-infrared (NIR) dye IRDye800CW-CA can be used to visualize ureters intraoperatively. METHODS: Adult female mixed-breed pigs weighing 24 to 41 kg (n = 2 per dose) were given a 30, 60, or 120 µg/kg systemic injection of IRDye800CW-CA. Using the Food and Drug Administration-cleared Pinpoint laparoscopic NIR system, images of the ureter and bladder were captured every 10 minutes for 60 minutes after injection. To determine the biodistribution of the dye, tissues were collected for ex vivo analysis with the Pearl Impulse system. ImageJ software was used to quantify fluorescence signal and signal-to-background ratio (SBR) for the intraoperative images. RESULTS: The ureter was identified in all pigs at each dose, with peak intensity reached by 30 minutes and remaining elevated throughout the duration of imaging (60 minutes). The 60 µg/kg dose was determined to be optimal for differentiating ureters according to absolute fluorescence (>60 counts/pixel) and SBR (3.1). Urine fluorescence was inversely related to plasma fluorescence (R(2) = -0.82). Ex vivo imaging of kidney, ureter, bladder, and abdominal wall tissues revealed low fluorescence. CONCLUSION: Systemic administration of IRDye800CW-CA shows promise in providing ureteral identification with high specificity during laparoscopic surgery. The low dose required, rapid time to visualization, and absence of invasive ureteral instrumentation inherent to this technique may reduce complications related to pelvic surgery.


Assuntos
Corantes Fluorescentes , Indóis , Laparoscopia/métodos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Ureter/patologia , Adulto , Animais , Modelos Animais de Doenças , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Suínos , Distribuição Tecidual , Ureter/lesões
14.
Ann Surg ; 261(1): 46-55, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25599326

RESUMO

OBJECTIVE: To review the current trends in optical imaging to guide oncologic surgery. BACKGROUND: Surgical resection remains the cornerstone of therapy for patients with early stage solid malignancies and more than half of all patients with cancer undergo surgery each year. The technical ability of the surgeon to obtain clear surgical margins at the initial resection remains crucial to improve overall survival and long-term morbidity. Current resection techniques are largely based on subjective and subtle changes associated with tissue distortion by invasive cancer. As a result, positive surgical margins occur in a significant portion of tumor resections, which is directly correlated with a poor outcome. METHODS: A comprehensive review of studies evaluating optical imaging techniques is performed. RESULTS: A variety of cancer imaging techniques have been adapted or developed for intraoperative surgical guidance that have been shown to improve functional and oncologic outcomes in randomized clinical trials. There are also a large number of novel, cancer-specific contrast agents that are in early stage clinical trials and preclinical development that demonstrate significant promise to improve real-time detection of subclinical cancer in the operative setting. CONCLUSIONS: There has been an explosion of intraoperative imaging techniques that will become more widespread in the next decade.


Assuntos
Diagnóstico por Imagem , Período Intraoperatório , Neoplasias/patologia , Neoplasias/cirurgia , Ácido Aminolevulínico , Neoplasias Encefálicas/cirurgia , Corantes , Corantes Fluorescentes , Humanos , Verde de Indocianina , Imagem Óptica , Fármacos Fotossensibilizantes , Cirurgia Assistida por Computador
15.
J Am Coll Surg ; 218(4): 554-62, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24529804

RESUMO

BACKGROUND: Public reporting of mortality, Patient Safety Indicators (PSI) and hospital-acquired conditions (HACs) is the reality of quality measurement. A review of our department's data identified opportunities for improvement. We began a surgeon-led 100% review of mortality, PSIs, and HACs to improve patient care and surgeon awareness of these metrics. STUDY DESIGN: From December 2012 through August 2013, there were 11,899 patients cared for on 12 surgical services. A surgeon from each service led monthly reviews of all mortality, PSIs, or HACs with central reporting of preventability and coding accuracy. We compared the University HealthSystem Consortium observed-to-expected (OE) mortality ratios (mean <1 fewer observed than expected deaths) and University HealthSystem Consortium relative rankings (lower number is better) before and after implementation. Statistical significance was p < 0.05 by Poisson regression. RESULTS: Of the 11,899 patients in the study period, there were 235 deaths, 290 PSIs, and 26 HACs identified and reviewed. The most common PSIs were postoperative deep vein thrombosis/pulmonary thromboembolism (n = 75), respiratory failure (n = 61), hemorrhage/hematoma (n = 33), and accidental puncture/laceration (n = 33). Before December 20, 2012, the OE ratio for mortality was consistently >1, then fell and remained <1 during the study period (p < 0.05). The OE mortality ratio in the fourth quarter of 2012 was 1.14 and fell to 0.88, 0.91, and 0.75 in the first, second, and third quarters of calendar year 2013 (p < 0.05). The overall Inpatient Quality Indicators #90 (composite postoperative mortality rank) rankings increased from 109 of 118 in the third quarter of 2012 to 47 of 119 in the third quarter of 2013. CONCLUSIONS: A surgeon-led systematic review of mortality, PSIs, and HACs improved our OE ratio and University HealthSystem Consortium postsurgical relative rankings. Surgeon engagement and ownership is critical for success.


Assuntos
Mortalidade Hospitalar , Complicações Intraoperatórias/epidemiologia , Segurança do Paciente/estatística & dados numéricos , Complicações Pós-Operatórias/epidemiologia , Melhoria de Qualidade/organização & administração , Indicadores de Qualidade em Assistência à Saúde/estatística & dados numéricos , Centro Cirúrgico Hospitalar/normas , Idoso , Alabama , Benchmarking , Hospitais Universitários/normas , Hospitais Universitários/estatística & dados numéricos , Humanos , Complicações Intraoperatórias/prevenção & controle , Erros Médicos , Pessoa de Meia-Idade , Complicações Pós-Operatórias/prevenção & controle , Estudos Prospectivos , Melhoria de Qualidade/estatística & dados numéricos , Centro Cirúrgico Hospitalar/organização & administração , Centro Cirúrgico Hospitalar/estatística & dados numéricos
16.
J Surg Res ; 188(1): 119-28, 2014 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-24360117

RESUMO

BACKGROUND: Complete surgical resection of breast cancer is a powerful determinant of patient outcome, and failure to achieve negative margins results in reoperation in between 30% and 60% of patients. We hypothesize that repurposing Food and Drug Administration-approved antibodies as tumor-targeting diagnostic molecules can function as optical contrast agents to identify the boundaries of malignant tissue intraoperatively. MATERIALS AND METHODS: The monoclonal antibodies bevacizumab, cetuximab, panitumumab, trastuzumab, and tocilizumab were covalently linked to a near-infrared fluorescence probe (IRDye800CW) and in vitro binding assays were performed to confirm ligand-specific binding. Nude mice bearing human breast cancer flank tumors were intravenously injected with the antibody-IRDye800 bioconjugates and imaged over time. Tumor resections were performed using the SPY and Pearl Impulse systems, and the presence or absence of tumor was confirmed by conventional and fluorescence histology. RESULTS: Tumor was distinguishable from normal tissue using both SPY and Pearl systems, with both platforms being able to detect tumor as small as 0.5 mg. Serial surgical resections demonstrated that real-time fluorescence can differentiate subclinical segments of disease. Pathologic examination of samples by conventional and optical histology using the Odyssey scanner confirmed that the bioconjugates were specific for tumor cells and allowed accurate differentiation of malignant areas from normal tissue. CONCLUSIONS: Human breast cancer tumors can be imaged in vivo with multiple optical imaging platforms using near-infrared fluorescently labeled antibodies. These data support additional preclinical investigations for improving the surgical resection of malignancies with the goal of eventual clinical translation.


Assuntos
Anticorpos Monoclonais Humanizados , Benzenossulfonatos , Neoplasias da Mama/patologia , Mama/patologia , Indóis , Raios Infravermelhos , Animais , Mama/cirurgia , Neoplasias da Mama/cirurgia , Linhagem Celular Tumoral , Feminino , Humanos , Cuidados Intraoperatórios/métodos , Período Intraoperatório , Camundongos Nus , Imagem Óptica
17.
Anticancer Drugs ; 25(2): 200-3, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24126240

RESUMO

We have previously shown that L-methionine inhibits proliferation of breast, prostate, and colon cancer cells. This study extends these findings to BXPC-3 (mutated p53) and HPAC (wild-type p53) pancreatic cancer cells and explores the reversibility of these effects. Cells were exposed to L-methionine (5 mg/ml) for 7 days or for 3 days, followed by 4 days of culture without L-methionine (recovery). Cell proliferation, apoptosis, and cell cycle effects were assessed by flow cytometry after staining for Ki-67 or annexin V/propidium iodide. Cell proliferation was reduced by 31-35% after 7 days of methionine exposure; the effect persisted in BXPC-3 and HPAC cells after 4 days of recovery. Methionine increased apoptosis by 40-75% in HPAC cells, but not in BXPC-3 cells. Continuous exposure to methionine caused accumulation of BXPC-3 cells in the S phase and HPAC cells in both the G0/G1 and S phases; however, after 4 days of recovery, these effects disappeared. In conclusion, L-methionine inhibits proliferation and interferes with the cell cycle of BXPC-3 and HPAC pancreatic cancer cells; the effects on apoptosis remarkably persisted after methionine withdrawal. Apoptosis was induced only in BXPC-3 cells. Some of the differences in the effects of methionine between cell lines may be related to disparate p53 status. These findings warrant further studies on the potential therapeutic benefit of L-methionine against pancreatic cancer.


Assuntos
Antineoplásicos/farmacologia , Metionina/farmacologia , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Humanos , Neoplasias Pancreáticas , Células Tumorais Cultivadas
18.
Mol Pharmacol ; 83(3): 698-708, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23292798

RESUMO

Examination of three retinoid X receptor (RXR) agonists [Targretin (TRG), UAB30, and 4-methyl-UAB30 (4-Me-UAB30)] showed that all inhibited mammary cancer in rodents and two (TRG and 4-Me-UAB30) strikingly increased serum triglyceride levels. Agents were administered in diets to female Sprague-Dawley rats. Liver RNA was isolated and microarrayed on the Affymetrix GeneChip Rat Exon 1.0 ST array. Statistical tests identified genes that exhibited differential expression and fell into groups, or modules, with differential expression among agonists. Genes in specific modules were changed by one, two, or all three agonists. An interactome analysis assessed the effects on genes that heterodimerize with known nuclear receptors. For proliferator-activated receptor α/RXR-activated genes, the strongest response was TRG > 4-Me-UAB30 > UAB30. Many liver X receptor/RXR-related genes (e.g., Scd-1 and Srebf1, which are associated with increased triglycerides) were highly expressed in TRG and 4-Me-UAB30- but not UAB30-treated livers. Minimal expression changes were associated with retinoic acid receptor or vitamin D receptor heterodimers by any of the agonists. UAB30 unexpectedly and uniquely activated genes associated with the aryl hydrocarbon hydroxylase (Ah) receptor (Cyp1a1, Cyp1a2, Cyp1b1, and Nqo1). Based on the Ah receptor activation, UAB30 was tested for its ability to prevent dimethylbenzanthracene (DMBA)-induced mammary cancers, presumably by inhibiting DMBA activation, and was highly effective. Gene expression changes were determined by reverse transcriptase-polymerase chain reaction in rat livers treated with Targretin for 2.3, 7, and 21 days. These showed similar gene expression changes at all three time points, arguing some steady-state effect. Different patterns of gene expression among the agonists provided insight into molecular differences and allowed one to predict certain physiologic consequences of agonist treatment.


Assuntos
Ácidos Graxos Insaturados/farmacologia , Expressão Gênica/efeitos dos fármacos , Fígado/efeitos dos fármacos , Naftalenos/farmacologia , Receptores X de Retinoides/agonistas , Tetra-Hidronaftalenos/farmacologia , 9,10-Dimetil-1,2-benzantraceno/farmacologia , Animais , Hidrocarboneto de Aril Hidroxilases/metabolismo , Bexaroteno , Feminino , Expressão Gênica/genética , Fígado/metabolismo , Receptores Ativados por Proliferador de Peroxissomo/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores de Hidrocarboneto Arílico/metabolismo , Receptores de Calcitriol/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Receptores do Ácido Retinoico/metabolismo , Receptores X de Retinoides/metabolismo , Triglicerídeos/sangue , beta-Naftoflavona/farmacologia
20.
Ann Surg ; 255(4): 611-7, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22367447

RESUMO

OBJECTIVE(S): The goals of this focused meeting were to verify and clarify the causes and extent of the general surgery (GS) workforce shortfalls. We also sought to define workable solutions within the existing framework of medical accreditation and certification. BACKGROUND: Numerous peer-reviewed and lay reports describe a current and worsening availability of GS services, affecting rural areas as well as large cities, academia, and the military. METHOD: Primary recommendations were broadly agreed upon by attendee surgeons who were selected from numerous different professional scenarios and included 2 nonmedical observers. RECOMMENDATIONS: (1) enhance the number of GS trainees and the breadth of training, (2) incorporate more flexibility and breadth in residency, (3) minimally invasive surgery should largely return to GS, (4) broader use of community hospitals in these efforts, (5) publicize loan forgiveness and improved visa status for international medical graduates going into GS, and (6) select candidates with a bias toward a general surgical career. CONCLUSION: These methods are promising approaches to this serious deficiency but will require regular reporting and publicity for the recording of actual increases in GS output.


Assuntos
Educação Médica , Cirurgia Geral , Acessibilidade aos Serviços de Saúde , Competência Clínica , Currículo , Educação Médica/economia , Educação Médica/métodos , Educação Médica/tendências , Médicos Graduados Estrangeiros/economia , Cirurgia Geral/economia , Cirurgia Geral/educação , Cirurgia Geral/tendências , Necessidades e Demandas de Serviços de Saúde , Hospitais Comunitários , Humanos , Medicina Militar , Procedimentos Cirúrgicos Minimamente Invasivos/educação , Procedimentos Cirúrgicos Minimamente Invasivos/tendências , Apoio ao Desenvolvimento de Recursos Humanos , Estados Unidos , Recursos Humanos
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