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1.
Ann Surg ; 280(2): 212-221, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38708880

RESUMO

OBJECTIVE: To determine the feasibility, efficacy, and safety of early cold stored platelet transfusion compared with standard care resuscitation in patients with hemorrhagic shock. BACKGROUND: Data demonstrating the safety and efficacy of early cold stored platelet transfusion are lacking following severe injury. METHODS: A phase 2, multicenter, randomized, open label, clinical trial was performed at 5 US trauma centers. Injured patients at risk of large volume blood transfusion and the need for hemorrhage control procedures were enrolled and randomized. The intervention was the early transfusion of a single apheresis cold stored platelet unit, stored for up to 14 days versus standard care resuscitation. The primary outcome was feasibility and the principal clinical outcome for efficacy and safety was 24-hour mortality. RESULTS: Mortality at 24 hours was 5.9% in patients who were randomized to early cold stored platelet transfusion compared with 10.2% in the standard care arm (difference, -4.3%; 95% CI, -12.8% to 3.5%; P =0.26). No significant differences were found for any of the prespecified ancillary outcomes. Rates of arterial and/or venous thromboembolism and adverse events did not differ across treatment groups. CONCLUSIONS AND RELEVANCE: In severely injured patients, early cold stored platelet transfusion is feasible, safe and did not result in a significant lower rate of 24-hour mortality. Early cold stored platelet transfusion did not result in a higher incidence of arterial and/or venous thrombotic complications or adverse events. The storage age of the cold stored platelet product was not associated with significant outcome differences. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT04667468.


Assuntos
Preservação de Sangue , Transfusão de Plaquetas , Choque Hemorrágico , Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Choque Hemorrágico/terapia , Choque Hemorrágico/etiologia , Preservação de Sangue/métodos , Estudos de Viabilidade , Ferimentos e Lesões/terapia , Ferimentos e Lesões/complicações , Resultado do Tratamento , Ressuscitação/métodos , Temperatura Baixa
2.
JAMA ; 324(10): 961-974, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32897344

RESUMO

Importance: Traumatic brain injury (TBI) is the leading cause of death and disability due to trauma. Early administration of tranexamic acid may benefit patients with TBI. Objective: To determine whether tranexamic acid treatment initiated in the out-of-hospital setting within 2 hours of injury improves neurologic outcome in patients with moderate or severe TBI. Design, Setting, and Participants: Multicenter, double-blinded, randomized clinical trial at 20 trauma centers and 39 emergency medical services agencies in the US and Canada from May 2015 to November 2017. Eligible participants (N = 1280) included out-of-hospital patients with TBI aged 15 years or older with Glasgow Coma Scale score of 12 or less and systolic blood pressure of 90 mm Hg or higher. Interventions: Three interventions were evaluated, with treatment initiated within 2 hours of TBI: out-of-hospital tranexamic acid (1 g) bolus and in-hospital tranexamic acid (1 g) 8-hour infusion (bolus maintenance group; n = 312), out-of-hospital tranexamic acid (2 g) bolus and in-hospital placebo 8-hour infusion (bolus only group; n = 345), and out-of-hospital placebo bolus and in-hospital placebo 8-hour infusion (placebo group; n = 309). Main Outcomes and Measures: The primary outcome was favorable neurologic function at 6 months (Glasgow Outcome Scale-Extended score >4 [moderate disability or good recovery]) in the combined tranexamic acid group vs the placebo group. Asymmetric significance thresholds were set at 0.1 for benefit and 0.025 for harm. There were 18 secondary end points, of which 5 are reported in this article: 28-day mortality, 6-month Disability Rating Scale score (range, 0 [no disability] to 30 [death]), progression of intracranial hemorrhage, incidence of seizures, and incidence of thromboembolic events. Results: Among 1063 participants, a study drug was not administered to 96 randomized participants and 1 participant was excluded, resulting in 966 participants in the analysis population (mean age, 42 years; 255 [74%] male participants; mean Glasgow Coma Scale score, 8). Of these participants, 819 (84.8%) were available for primary outcome analysis at 6-month follow-up. The primary outcome occurred in 65% of patients in the tranexamic acid groups vs 62% in the placebo group (difference, 3.5%; [90% 1-sided confidence limit for benefit, -0.9%]; P = .16; [97.5% 1-sided confidence limit for harm, 10.2%]; P = .84). There was no statistically significant difference in 28-day mortality between the tranexamic acid groups vs the placebo group (14% vs 17%; difference, -2.9% [95% CI, -7.9% to 2.1%]; P = .26), 6-month Disability Rating Scale score (6.8 vs 7.6; difference, -0.9 [95% CI, -2.5 to 0.7]; P = .29), or progression of intracranial hemorrhage (16% vs 20%; difference, -5.4% [95% CI, -12.8% to 2.1%]; P = .16). Conclusions and Relevance: Among patients with moderate to severe TBI, out-of-hospital tranexamic acid administration within 2 hours of injury compared with placebo did not significantly improve 6-month neurologic outcome as measured by the Glasgow Outcome Scale-Extended. Trial Registration: ClinicalTrials.gov Identifier: NCT01990768.


Assuntos
Antifibrinolíticos/administração & dosagem , Lesões Encefálicas Traumáticas/tratamento farmacológico , Ácido Tranexâmico/administração & dosagem , Adulto , Antifibrinolíticos/efeitos adversos , Encefalopatias/etiologia , Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/mortalidade , Método Duplo-Cego , Serviços Médicos de Emergência , Feminino , Seguimentos , Escala de Coma de Glasgow , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Gravidade do Paciente , Análise de Sobrevida , Tempo para o Tratamento , Ácido Tranexâmico/efeitos adversos
3.
J Surg Res ; 233: 276-283, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30502260

RESUMO

BACKGROUND: Missing doses of antibiotics in hospitalized patients is a well-described but inadequately recognized issue. We hypothesized that missing doses of antibiotics decreases quality of care. METHODS: Retrospective study on patients admitted to the Shock Trauma ICU from February to June 2015. Patients prescribed a multidose course of antibiotics were evaluated. A missed antibiotic dose was one ordered but never given (a completely missed dose) or a dose that was not given within an hour before or after the planned time (an off-schedule missed dose). Patient outcomes included a positive culture, ventilator, ICU and hospital length of stay (LOS), and mortality. Multiple statistical methods were used as appropriate; significance was set as P < 0.05. RESULTS: For the 5-mo study period, 280 patients were admitted and 200 met inclusion criteria. Eight percent of patients (16/200) did not miss any antibiotic doses, 39% (77/200) had only off-schedule doses, 2% (4/200) had only completely missed doses, and 51% (103/200) had both off-schedule and completely missed doses. For the 200 patients, 8167 doses were ordered and 2096 (26%) were missed. Adjusting for age, gender, BMI, injury severity score, and doses of antibiotics showed that those who miss doses off-schedule had longer LOS than those who do not miss doses of antibiotics. There was a significant nonlinear relationship between LOS and frequency of early (P-value = 0.02) and late (P-value = 0.01) doses. CONCLUSIONS: To reduce length of hospital stay and optimize quality, methods to improve compliance with antibiotic dosing schedules should be investigated.


Assuntos
Antibacterianos/administração & dosagem , Erros de Medicação/estatística & dados numéricos , Avaliação de Processos e Resultados em Cuidados de Saúde/estatística & dados numéricos , Ferimentos e Lesões/tratamento farmacológico , Adulto , Idoso , Prescrições de Medicamentos/estatística & dados numéricos , Feminino , Mortalidade Hospitalar , Humanos , Escala de Gravidade do Ferimento , Unidades de Terapia Intensiva/estatística & dados numéricos , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Qualidade da Assistência à Saúde , Estudos Retrospectivos , Centros de Traumatologia/estatística & dados numéricos , Ferimentos e Lesões/diagnóstico , Ferimentos e Lesões/mortalidade
4.
J Surg Res ; 234: 65-71, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30527501

RESUMO

BACKGROUND: Exception from informed consent (EFIC) allows clinician scientists to perform much needed emergency research. Obtaining this exception, however, requires many meetings with community groups for consultation, which can make the process time-consuming and expensive. We aim to determine the impact of using social media in lieu of some community meetings in an effort to obtain an EFIC. MATERIALS AND METHODS: An economic analysis of four randomized clinical trials was performed. Costs were conservatively estimated using personnel costs, social media costs, and adjusted to 2016 US dollars. People were considered reached if they attended a community meeting or were directed to the study website by social media and spent ≥1 min. RESULTS: The Early Whole Blood study required 14 meetings, reached 272 people, and cost $8260 ($30/person reached). The Pragmatic, Randomized Optimal Platelet and Plasma Ratios study required 14 meetings, reached 260 people, and cost $7479 overall ($29/person reached). The Prehospital Tranexamic Acid Use for Traumatic Brain Injury study required 12 meetings, reached 198 people, and cost $6340 ($32/person reached). Only the damage control laparotomy trial utilized social media in lieu of some community meetings. The damage control laparotomy trial required six meetings at which 137 people were reached. The $1000 social media campaign reached 229 people. The cost was $3977 overall and $11/person reached. CONCLUSIONS: Including a social media campaign during the EFIC process increased the number of potential patients reached and reduced total and per person costs reached costs. Obtaining an EFIC for future emergency clinical trials may be facilitated by the inclusion of a social media campaign.


Assuntos
Participação da Comunidade/economia , Tratamento de Emergência , Consentimento Livre e Esclarecido , Ensaios Clínicos Controlados Aleatórios como Assunto/economia , Mídias Sociais , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
5.
J Neurosurg ; : 1-10, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-39076152

RESUMO

OBJECTIVE: Traumatic brain injury (TBI) and hemorrhage are responsible for the largest proportion of all trauma-related deaths. In polytrauma patients at risk of hemorrhage and TBI, the diagnosis, prognosis, and management of TBI remain poorly characterized. The authors sought to characterize the predictive capabilities of glial fibrillary acidic protein (GFAP) and ubiquitin C-terminal hydrolase L1 (UCH-L1) measurements in patients with hemorrhagic shock with and without concomitant TBI. METHODS: The authors performed a secondary analysis on serial blood samples derived from a prospective observational cohort study that focused on comparing early whole-blood and component resuscitation. A convenience sample of patients was used in which samples were collected at three time points and the presence of TBI or no TBI via CT imaging was documented. GFAP and UCH-L1 measurements were performed on plasma samples using the i-STAT Alinity point-of-care platform. Using classification tree recursive partitioning, the authors determined the measurement cut points for each biomarker to maximize the abilities for predicting the diagnosis of TBI, Rotterdam CT imaging scores, and 6-month Glasgow Outcome Scale-Extended (GOSE) scores. RESULTS: Biomarker comparisons demonstrated that GFAP and UCH-L1 measurements were associated with the presence of TBI at all time points. Classification tree analyses demonstrated that a GFAP level > 286 pg/ml for the sample taken upon the patient's arrival had an area under the receiver operating characteristic curve of 0.77 for predicting the presence of TBI. The classification tree results demonstrated that a cut point of 3094 pg/ml for the arrival GFAP measurement was the most predictive for an elevated Rotterdam score on the initial and second CT scans and for TBI progression between scans. No significant associations between any of the most predictive cut points for UCH-L1 and Rotterdam CT scores or TBI progression were found. The predictive capabilities of UCH-L1 were limited by the range allowed by the point-of-care platform. Arrival GFAP cut points remained strong independent predictors after controlling for all potential polytrauma confounders, including injury characteristics, shock severity, and resuscitation. CONCLUSIONS: Early measurements of GFAP and UCH-L1 on a point-of-care device are significantly associated with CT-diagnosed TBI in patients with polytrauma and shock. Early elevated GFAP measurements are associated with worse head CT scan Rotterdam scores, TBI progression, and worse GOSE scores, and these associations are independent of other injury attributes, shock severity, and early resuscitation characteristics.

6.
JAMA Surg ; 157(8): 713-721, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35731524

RESUMO

Importance: Venous thromboembolism (VTE) affects 2% to 20% of recovering trauma patients, despite aggressive prophylaxis with enoxaparin. Antithrombin is a primary circulating anticoagulant and crucial component of enoxaparin thromboprophylaxis. Approximately 20% of trauma patients present with antithrombin deficiency (antithrombin activity <80%). Objective: To examine time-dependent changes in antithrombin activity, responsiveness to enoxaparin, as measured by anti-factor Xa (anti-FXa) levels, and incidence of VTE after severe trauma and to assess the association of ex vivo antithrombin supplementation with patients' sensitivity to enoxaparin prophylaxis. Design, Setting, and Participants: This single-center, prospective cohort study was performed at a level 1 trauma center between January 7, 2019, and February 28, 2020. Adult trauma patients admitted to the trauma service at high risk for VTE, based on injury pattern and severity, were screened and enrolled. Patients who were older than 70 years, were pregnant, had a known immunologic or coagulation disorder, or were receiving prehospital anticoagulants were excluded. Exposures: Blood samples were collected on emergency department arrival and daily for the first 8 days of hospitalization. Main Outcomes and Measures: Patients' antithrombin activity and anti-FXa levels were measured by a coagulation analyzer, and thrombin generation was measured by calibrated automated thrombography. Responsiveness to enoxaparin was assessed by measuring anti-FXa levels 4 to 6 hours after the first daily enoxaparin dose and compared between patients who developed VTE and who did not. In addition, the associations of ex vivo supplementation of antithrombin with plasma anti-FXa levels were assessed. Results: Among 150 patients enrolled (median [IQR] age, 35 [27-53] years; 37 [24.7%] female and 113 [75.3%] male; 5 [3.3%] Asian, 32 [21.3%] Black, and 113 [75.3%] White; and 51 [34.0%] of Hispanic ethnicity), 28 (18.7%) developed VTE. Patients with VTE had significantly lower antithrombin activity on admission compared with patients without VTE (median [IQR], 91% [79%-104%] vs 100% [88%-112%]; P = .04), as well as lower antithrombin activity on hospital days 5 (median (IQR), 90% [83%-99%] vs 114% [99%-130%]; P = .011), 6 (median [IQR], 97% [81%-109%] vs 123% [104%-134%]; P = .003), 7 (median [IQR], 82% [74%-89%] vs 123% [110%-140%]; P < .001), and 8 (median [IQR], 99% [85%-100%] vs 123% [109%-146%]; P = .011). Anti-FXa levels were significantly lower in patients with VTE vs those without VTE at hospital day 4 (median [IQR], 0.10 [0.05-0.14] IU/mL vs 0.18 [0.13-0.23] IU/mL; P = .006), day 6 (median [IQR], 0.12 [0.08-0.14] IU/mL vs 0.22 [0.13-0.28] IU/mL; P = .02), and day 7 (median [IQR], 0.11 [0.08-0.12] IU/mL vs 0.21 [0.13, 0.28] IU/mL; P = .002). Multivariable analyses found that for every 10% decrease in antithrombin activity during the first 3 days, the risk of VTE increased 1.5-fold. Conclusions and Relevance: The results of this cohort study suggest that after severe trauma, antithrombin deficiency is common and contributes to enoxaparin resistance and VTE. Interventional studies are necessary to determine the efficacy of antithrombin supplementation in the reduction of VTE incidence.


Assuntos
Enoxaparina , Tromboembolia Venosa , Adulto , Anticoagulantes/uso terapêutico , Antitrombinas/uso terapêutico , Estudos de Coortes , Enoxaparina/uso terapêutico , Feminino , Humanos , Masculino , Estudos Prospectivos , Tromboembolia Venosa/epidemiologia , Tromboembolia Venosa/etiologia , Tromboembolia Venosa/prevenção & controle
7.
Trauma Surg Acute Care Open ; 3(1): e000192, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30206549

RESUMO

BACKGROUND: Pain management after injury is critically important for functional recovery. Although opioids have been a mainstay for treatment of pain, they are associated with adverse events and may contribute to long-term use or abuse. Opioid-minimizing multimodal pain regimens have the potential to reduce exposure to opioids without compromising pain control. This article details an ongoing clinical trial comparing two pill-based, opioid-minimizing, multimodal pain strategies. METHODS: This is a single-center, parallel-group, randomized, controlled comparative effectiveness trial comparing two multimodal pain regimens in adult trauma patients. All patients 16 years and older admitted to the Red Duke Trauma Institute are eligible unless they are pregnant, a prisoner, under observation status, or a non-acute trauma patient. At admission to the trauma service, patients are enrolled and randomized to one of two multimodal pain regimens. The primary outcome is opioid use, measured by morphine milligram equivalents per patient per day. The secondary outcomes include pain scores, ventilator days, hospital and intensive care unit lengths of stay, occurrence of opioid-related complications, hospital and pharmacy costs, and incidence of hospital discharge with opioid prescription. Outcomes will be compared using Bayesian methods. DISCUSSION: This trial will determine the effectiveness of two multimodal pain treatment strategies on reducing in-hospital opioid exposure in adult trauma patients. Furthermore, it will compare the two strategies on pain control and patient safety. Knowledge gained in this study can improve quality of care at this hospital and other trauma centers regardless of which medication regimen proves superior.

8.
J Trauma Acute Care Surg ; 83(1): 19-24, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28452870

RESUMO

BACKGROUND: American College of Surgeons Trauma Quality Improvement Best Practices recommends initial massive transfusion (MT) cooler delivery within 15 minutes of protocol activation, with a goal of 10 minutes. The current study sought to examine the impact of timing of first cooler delivery on patient outcomes. METHODS: Patients predicted to receive MT at 12 Level I trauma centers were randomized to two separate transfusion ratios as described in the PROPPR trial. Assessment of Blood Consumption score or clinician gestalt prediction of MT was used to randomize patients and call for initial study cooler. In this planned subanalysis, the time to MT protocol activation and time to delivery of the initial cooler were evaluated. The impact of these times on mortality and time to hemostasis were examined using both Wilcoxon rank sum and linear and logistic regression. RESULTS: Among 680 patients, the median time from patient arrival to MT protocol activation was 9 minutes with a median time from MT activation call to delivery of first cooler of 8 minutes. An increase in both time to MT activation and time to arrival of first cooler were associated with prolonged time to achieving hemostasis (coefficient, 1.09; p = 0.001 and coefficient, 1.16; p < 0.001, respectively). Increased time to MT activation and time to arrival of first cooler were associated with increased mortality (odds ratio [OR], 1.02; p = 0.009 and OR, 1.02; p = 0.012, respectively). Controlling for injury severity, physiology, resuscitation intensity, and treatment arm (1:1:1 vs. 1:1:2), increased time to arrival of first cooler was associated with an increased mortality at 24 hours (OR, 1.05; p = 0.035) and 30 days (OR, 1.05, p = 0.016). CONCLUSION: Delays in MT protocol activation and delays in initial cooler arrival were associated with prolonged time to achieve hemostasis and an increase in mortality. Independent of products ratios, every minute from time of MT protocol activation to time of initial cooler arrival increases odds of mortality by 5%. LEVEL OF EVIDENCE: Prognostic, level II; Therapeutic, level III.


Assuntos
Transfusão de Componentes Sanguíneos/métodos , Hemorragia/mortalidade , Hemorragia/terapia , Mortalidade Hospitalar , Ressuscitação/métodos , Ferimentos e Lesões/mortalidade , Ferimentos e Lesões/terapia , Adulto , Feminino , Humanos , Escala de Gravidade do Ferimento , Masculino , Pessoa de Meia-Idade , América do Norte , Análise de Sobrevida , Fatores de Tempo , Centros de Traumatologia
9.
Trauma Surg Acute Care Open ; 2(1): e000083, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29766087

RESUMO

BACKGROUND: Damage control laparotomy (DCL) is an abbreviated operation intended to prevent the development of hypothermia, acidosis, and coagulopathy in seriously injured patients. The indications for DCL have since been broadened with no high-quality data to guide treatment. For patients with an indication for DCL, we aim to determine the effect of definitive laparotomy on patient morbidity. METHOD: This is a pragmatic, parallel-group, randomized controlled pilot trial. Emergent laparotomy is defined as admission directly to the operating room from the emergency department within 90 min of arrival. DCL indications excluded from the study include packing of the liver or retroperitoneum, abdominal compartment syndrome prophylaxis, to expedite interventional radiology for hemorrhage control, and the need for ongoing transfusions and/or continuous vasopressor support. When a surgeon determines a DCL is indicated, the patient will be screened for inclusion and exclusion criteria. Patients with any indication for DCL that is not excluded are eligible for randomization. Patients will be randomized intraoperatively to DCL (control) or definitive fascial closure of the laparotomy (intervention). The primary outcome will be major abdominal complication or death within 30 days. Major abdominal complication is a composite outcome including fascial dehiscence, organ/space surgical site infection, enteric suture line failure, and unplanned reopening of the abdomen. Outcomes will be compared using both frequentist and Bayesian statistics. DISCUSSION: In patients with an indication for DCL, this trial will determine the effect of definitive laparotomy on major abdominal complications and death and will inform clinicians on the risks and benefits of this procedure. Regardless of the study outcome, the results will improve the quality of care provided to injured patients. TRIAL REGISTRATION NUMBER: NCT02706041.

10.
J Trauma Acute Care Surg ; 83(2): 241-248, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28731937

RESUMO

BACKGROUND: There is no consensus on reporting nonmortality trauma complications in a graded manner. The Clavien-Dindo scale of complications was originally for elective surgery and requires adaptation to provide meaningful data for trauma patients. In particular, the original score does not account for those treated without surgery. We report an adapted Clavien-Dindo in trauma (ACDiT) scale and apply it to patients managed operatively and nonoperatively. METHODS: A combined prospective and retrospective international multicenter observational study was undertaken to apply the ACDiT scale to 484 trauma patients at three university teaching hospitals (Birmingham, England (n = 303); Houston, Texas (n = 113); and Glasgow, Scotland (n = 68)). These included both intensive care unit (ICU) and non-ICU-managed patients. The Clavien-Dindo scoring system was adapted for trauma patients based on consensus amongst an international collaboration of trauma specialists at these sites. Data included whether initial patients were managed operatively or nonoperatively. Complication grades were compared with hospital-free and ICU-free days as other outcome measures of patient morbidity. RESULTS: Two hundred seventeen (44.8%) of 484 patients experienced complications, of whom 61 (28.1%) of 217 died (grade V). The remainder consisted of grades I (n = 20), II (n = 60), III (n = 24), and IV (n = 52). There was a strong association between higher ACDiT grade category and lower number of hospital-free and ICU-free days (p < 0.01). Eighty-eight patients with complications did not require surgery, validating the score's usefulness in patients managed nonoperatively. CONCLUSION: The ACDiT scale can be used to grade the severity of posttrauma complications in patients managed both operatively and nonoperatively. It provides clinically meaningful data for morbidity and mortality meetings and other quality improvement exercises. LEVEL OF EVIDENCE: Prognostic, level IV.


Assuntos
Índices de Gravidade do Trauma , Ferimentos e Lesões/complicações , Ferimentos e Lesões/mortalidade , Adulto , Causas de Morte , Coleta de Dados/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes , Estudos Retrospectivos , Análise de Sobrevida , Centros de Traumatologia/estatística & dados numéricos , Ferimentos e Lesões/classificação , Ferimentos e Lesões/terapia , Adulto Jovem
11.
J Surg Res ; 134(1): 44-51, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16678856

RESUMO

BACKGROUND: Cyclooxygenase-2 (COX-2) overexpression by a primary tumor correlates with poor prognosis in breast cancer, including early spread to bone. Interleukin-8 (IL-8) stimulates osteoclastogenesis and resorption of bone, and elevated IL-8 levels predict early metastatic spread of breast cancer. The purpose of this study was to test our hypothesis that tumors that overexpress COX-2 induce IL-8 production. MATERIALS AND METHODS: We cotransfected MCF-10A (nonmalignant breast epithelial) cells, as well as MDA-231 (highly metastatic human breast cancer) cell lines with a pSG5-COX-2 vector and pEF1a-Luc-IRES-Neo vector (luciferase reporter). COX-2 overexpression was confirmed by Western blot and PGE2 (a product of the COX-2 pathway) immunoassay. IL-8 production was measured by immunoassay. In vivo testing used a nude mouse model to measure COX-2 and IL-8 production from breast cancer cells that had metastasized to bone (bone-seeking clones (BSCs)). Long bone metastases were localized and quantified by luciferase imaging (Xenogen IVIS system) and X-ray. BSCs were isolated and cultured and then tested for the production of PGE2 and IL-8. RESULTS: COX-2 overexpression caused a 4- to 5-fold increase in IL-8 production in both MCF-10A and MDA-231 cells in vitro. In vivo, we observed that the MDA-231-BSC (metastatic cells isolated from bone metastases) produced significantly greater levels of both PGE2 and IL-8 compared to the parental MDA-231 cells (P < 0.01). In contrast to the results obtained with these estrogen receptor-negative cell lines, COX-2 expression failed to induce IL-8 in the MCF-7 estrogen receptor-positive breast cancer cell line. Treatment with the COX-2 inhibitor NS-398 at a low 1-mu[scap]M dose reduced the production of IL-8 in COX-2-transfected MDA-231 cells by 30%, thus confirming the involvement of COX-2 in IL-8 induction. CONCLUSION: COX-2 expression induced formation of PGE2 and IL-8 in breast cancer cells. Since PGE2 and IL-8 stimulate osteoclasts to resorb bone, COX-2 inhibition is a potential target for treatment to prevent bone metastases.


Assuntos
Neoplasias Ósseas/secundário , Neoplasias da Mama/patologia , Ciclo-Oxigenase 2/fisiologia , Interleucina-8/fisiologia , Animais , Linhagem Celular Tumoral , Inibidores de Ciclo-Oxigenase 2/farmacologia , Feminino , Humanos , Interleucina-8/biossíntese , Camundongos , Camundongos Nus , Processamento de Proteína Pós-Traducional
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