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1.
World J Surg ; 43(5): 1264-1270, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30610270

RESUMEN

Hereditary breast cancers, mainly due to BRCA1 and BRCA2 mutations, account for only 5-10% of this disease. The threshold for genetic testing is a 10% likelihood of detecting a mutation, as determined by validated models such as BOADICEA and Manchester Scoring System. A 90-95% reduction in breast cancer risk can be achieved with bilateral risk-reducing mastectomy in unaffected BRCA mutation carriers. In patients with BRCA-associated breast cancer, there is a 40% risk of contralateral breast cancer and hence risk-reducing contralateral mastectomy is recommended, which can be performed simultaneously with surgery for unilateral breast cancer. Other options for risk management include surveillance by mammogram and breast magnetic resonance imaging, and chemoprevention with hormonal agents. With the advent of next-generation sequencing and development of multigene panel testing, the cost and time taken for genetic testing have reduced, making it possible for treatment-focused genetic testing. There are also drugs such as the PARP inhibitors that specifically target the BRCA mutation. Risk management multidisciplinary clinics are designed to quantify risk, and offer advice on preventative strategies. However, such services are only possible in high-income settings. In low-resource settings, the prohibitive cost of testing and the lack of genetic counsellors are major barriers to setting up a breast cancer genetics service. Family history is often not well documented because of the stigma associated with cancer. Breast cancer genetics services remain an unmet need in low- and middle-income countries, where the priority is to optimise access to quality treatment.


Asunto(s)
Neoplasias de la Mama/genética , Consejo , Pruebas Genéticas , Neoplasias de la Mama/terapia , Femenino , Genes BRCA1 , Genes BRCA2 , Humanos , Mutación
2.
Curr Oncol ; 23(6): e615-e625, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28050152

RESUMEN

In recent years, risk stratification has sparked interest as an innovative approach to disease screening and prevention. The approach effectively personalizes individual risk, opening the way to screening and prevention interventions that are adapted to subpopulations. The international perspective project, which is developing risk stratification for breast cancer, aims to support the integration of its screening approach into clinical practice through comprehensive tool-building. Policies and guidelines for risk stratification-unlike those for population screening programs, which are currently well regulated-are still under development. Indeed, the development of guidelines for risk stratification reflects the translational aspects of perspective. Here, we describe the risk stratification process that was devised in the context of perspective, and we then explain the consensus-based method used to develop recommendations for breast cancer screening and prevention in a risk-stratification approach. Lastly, we discuss how the recommendations might affect current screening policies.

3.
Curr Oncol ; 22(1): 25-32, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25684986

RESUMEN

BACKGROUND: In cases of locally advanced breast cancer (labc), preoperative ("neoadjuvant") therapy was traditionally reserved to render the patient operable. More recently, neoadjuvant therapy, particularly chemotherapy, is being used in patients with operable disease to increase the opportunity for breast conservation. Despite the increasing use of preoperative chemotherapy, rates of pathologic complete response, a surrogate marker for disease-free survival, remain modest in patients with locally advanced disease and particularly so when the tumour is estrogen or progesterone receptor-positive and her2-negative. A new paradigm for labc patients is needed. In other solid tumours (for example, rectal, esophageal, and lung cancers), concurrent chemoradiotherapy (ccrt) is routinely used in neoadjuvant and adjuvant treatment protocols alike. RESULTS: The literature suggests that ccrt in labc patients with inoperable disease is associated with response rates higher than would be anticipated with systemic therapy alone. CONCLUSIONS: Ongoing trials in this field are eagerly awaited to determine if ccrt should become the new paradigm.

4.
Colorectal Dis ; 16(2): O66-70, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24148225

RESUMEN

AIM: A prospective phase II study to investigate the feasibility and the rate of complete pathological response (ypT0) after short-course radiotherapy (SCRT) followed by surgery at 8 weeks. METHOD: Operable patients with localized rectal cancer staged T3-4N0/+ or T2N+ were eligible and received 25 Gy (in one-third of patients, the gross tumor volume received a simultaneous integrated boost up to a total of 30 Gy) in five consecutive fractions to the posterior pelvis followed by surgery 8 weeks later. Pathological response and surgical toxicity were assessed in all patients. RESULTS: Fifty-two patients (median age 68 years) completed the study. The median distance of the tumour from the anal verge was 6.5 cm. The median interval to surgery was 52 days. Three-quarters of patients underwent a low anterior resection. All underwent complete surgical resection and 100% had pathological negative margins. Ten per cent had stage ypT0 after radiotherapy. The median length of hospital stay was 8 days. Toxicity was comparable with the rates reported in the literature. CONCLUSION: In this study, SCRT followed by delayed surgery was feasible and had acceptable toxicity. All patients underwent complete surgical resection and 100% had negative pathological margins. The rate of ypT0 was 10%.


Asunto(s)
Adenocarcinoma/radioterapia , Terapia Neoadyuvante/métodos , Neoplasias del Recto/radioterapia , Recto/cirugía , Adenocarcinoma/patología , Adenocarcinoma/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Radioterapia Adyuvante , Neoplasias del Recto/patología , Neoplasias del Recto/cirugía , Factores de Tiempo , Resultado del Tratamiento , Carga Tumoral
5.
Br J Surg ; 99(3): 336-44, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22241280

RESUMEN

BACKGROUND: Short duty hours, imposed by the Accreditation Council of Graduate Medical Education (ACGME) regulations, have been claimed to be associated with loss of continuity of care among surgical patients, leading to a potentially increased risk of adverse surgical outcomes. This systematic review and meta-analysis assessed the strength of associations between duty hour restrictions and morbidity and mortality of various surgical procedures. METHODS: MEDLINE, Embase, BIOSIS Previews(®), the Education Resources Information Center and the Cochrane Central Register of Controlled Trials (January 2000 to September 2009) were searched, and reports screened to identify comparative studies of mortality and morbidity before and after the introduction of ACGME regulation periods. Random-effects (RE) and quality-effects (QE) meta-analyses were performed to determine the risk of morbidity or death associated with long duty hours compared with shorter duty hours. Results are presented as odds ratio (OR) with 95 per cent confidence interval. RESULTS: A total of 19 data sets (10 articles), including 730,648 subjects in the mortality studies and 64,346 in the morbidity studies, were analysed. Long duty hours were associated with a non-significantly increased risk of death compared with shorter duty hours (OR 1·28, 0·94 to 1·73). There was no difference in morbidity between the two groups (OR 1·03, 0·67 to 1·57). Mortality associations were generally stronger for general surgery, more recent studies and higher-quality studies. Heterogeneity was evident among the studies included. CONCLUSION: The reduction in working hours has not affected patient care negatively in terms of demonstrable differences in morbidity and mortality. However, it cannot be distinguished whether this effect is actually due to a non-detrimental effect of the reduction in working hours or whether any such detriment is offset by continually improving patient care and increased surgical supervision.


Asunto(s)
Competencia Clínica/normas , Internado y Residencia/organización & administración , Procedimientos Quirúrgicos Operativos/mortalidad , Tolerancia al Trabajo Programado , Humanos , Internado y Residencia/normas , Sesgo de Publicación , Calidad de la Atención de Salud , Procedimientos Quirúrgicos Operativos/normas , Tasa de Supervivencia , Estados Unidos
6.
Ann Surg Oncol ; 17(5): 1414-21, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20131017

RESUMEN

BACKGROUND: Standard of care is to perform a complete lymph node dissection (CLND) in melanoma patients with positive sentinel lymph nodes (SLNs). However, less than 20% will have metastases in non-SLNs. The S classification was described to predict the non-SLN status, hoping to identify a subset of patients who can be spared the CLND. We tried to validate the feasibility and usefulness of this classification. MATERIALS AND METHODS: We performed a retrospective chart review. All melanoma cases between 1996 and 2006 were included, and 359 patients with SLN biopsies were identified. All pathology slides were reviewed with an emphasis on the S classification. RESULTS: There were 365 SLN biopsies performed. A total of 82 patients (22.8%) had positive SLNs, while 277 patients (77.2%) had negative SLNs. There were 22 patients classified as SI, 18 as SII, 37 as SIII, and 5 were unclassified. On CLND, only 10 patients (12.2%) had positive non-SLNs. None of these were classified as SI while 2 patients (11%) were classified as SII and 8 (22%) as SIII. The S category was found to be a predictor of non-SLN status, and this reached statistical significance (P = 0.044). On univariate analysis, only an increasing Breslow depth and ulceration were predictive of a non-SI status. CONCLUSION: Our results suggest that the S classification is easily feasible and predicts the status of non-SLNs. No patient with SI status was found to have additional non-SLN positive nodes. A larger-scale, prospective trial should be done to confirm these results and possibly spare patients the morbidity of CLND with a positive SLN.


Asunto(s)
Ganglios Linfáticos/patología , Melanoma/clasificación , Melanoma/patología , Biopsia del Ganglio Linfático Centinela , Canadá , Estudios de Factibilidad , Femenino , Humanos , Metástasis Linfática , Masculino , Melanoma/cirugía , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos
7.
Br J Surg ; 92(8): 947-53, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16034820

RESUMEN

BACKGROUND: The observed failure of hypocaloric nutrition to establish an anabolic state after surgery may reflect inadequate control for the type and quality of analgesia in the studies performed. This study was designed to test the hypothesis that hypocaloric nutrition induces anabolism in patients who receive effective segmental pain relief using perioperative epidural analgesia. METHODS: Sixteen patients who underwent colorectal surgery and received epidural analgesia were randomly assigned to receive intravenous glucose either without (glucose only) or with amino acids (nutrition). Feeding was administered over 48 h from surgical skin incision until the second day after operation. Glucose provided 50 per cent of the patient's resting energy expenditure (REE). Amino acids were infused at rates that provided 20 per cent of REE. Leucine rate of appearance (Ra), leucine oxidation and non-oxidative leucine disposal (NOLD) were assessed by measuring L-[1-13C]leucine kinetics. A positive leucine balance, that is the difference between NOLD and leucine Ra, indicated anabolism. RESULTS: After surgery, leucine Ra in the nutrition group was lower than that in the glucose only group (mean(s.d.) 88(25) versus 131(22) micromol per kg per h). The leucine balance remained negative in the glucose only group, whereas it became positive in the nutrition group (mean(s.d.) -24(3) versus 38(12) micromol per kg per h; P < 0.001). CONCLUSION: Patients who receive hypocaloric parenteral nutrition can be rendered anabolic after colorectal surgery in the presence of epidural analgesia.


Asunto(s)
Aminoácidos/metabolismo , Analgesia Epidural , Neoplasias del Colon/cirugía , Dieta Reductora , Glucosa/administración & dosificación , Nutrición Parenteral/métodos , Aminoácidos/administración & dosificación , Glucemia/metabolismo , Neoplasias del Colon/metabolismo , Femenino , Humanos , Infusiones Intravenosas , Cuidados Intraoperatorios/métodos , Leucina/administración & dosificación , Leucina/metabolismo , Masculino , Persona de Mediana Edad , Dolor Postoperatorio/metabolismo , Dolor Postoperatorio/prevención & control , Periodo Posoperatorio
9.
Am Surg ; 67(10): 943-7, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11603550

RESUMEN

Merkel cell carcinoma (MCC) is a highly aggressive primary neuroendocrine tumor. It is suggested in the literature that postoperative radiotherapy may decrease local recurrence and improve overall survival. The purpose of this retrospective review was to determine our experience and review the literature on this aggressive malignancy. Charts of ten patients with MCC seen between 1985 and 1997 were reviewed to obtain clinicopathological data. Eight patients were male with a mean age of 72 years (range 49-90). The head and neck was the most common site, affecting 50 per cent of patients. All patients had primary excisions with documented negative margins. Pathological size ranged from 10 to 40 mm. Initial pathological diagnosis was lymphoma in three cases requiring immunohistochemistry for cytokeratin and neuron-specific enolase for definitive diagnosis. Lymphatic invasion was noted in three patients but only one of these patients had clinical lymph node involvement. The mean follow-up was 54 months (range 6-114) with an 80 per cent one-year survival and 30 per cent 2-year survival. Postoperative radiotherapy was administered to five patients. Of these three died with evidence of both local and distant recurrence. This small retrospective review highlights important points in the management of MCC including pathological diagnosis and benefits of adjuvant radiation therapy.


Asunto(s)
Carcinoma de Células de Merkel/patología , Carcinoma de Células de Merkel/cirugía , Neoplasias Cutáneas/patología , Neoplasias Cutáneas/cirugía , Anciano , Anciano de 80 o más Años , Carcinoma de Células de Merkel/secundario , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/epidemiología , Estudios Retrospectivos
10.
Ann Surg Oncol ; 8(6): 533-7, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11456053

RESUMEN

BACKGROUND: Currently, the use of adjuvant therapy specifically in Dukes' B colon cancers is controversial, emphasizing the importance of identifying prognostic markers to select patients for such therapy. Bcl-2 plays an important role in apoptosis regulation of solid tumors, such as colon and breast cancer, and is normally expressed in the base of the colonic crypts. The purpose of this study is to determine whether or not bcl-2 expression can be used to predict survival in Dukes' B colon cancer patients. METHODS: Charts of 76 patients operated on at the Royal Victoria Hospital from 1986 to 1992 were reviewed. Bcl-2 staining was done with the avidin-biotin-peroxidase complex method using commercially available monoclonal bcl-2 antibodies. Two pathologists graded the intensity of bcl-2 staining on a scale of 0-3 and estimated the percentage of tumor cells staining positively (T-percent). Univariate and multiple regression of factors on overall survival (OS) and disease-free survival (DFS) was done with a Cox proportional hazards model and Kaplan-Meier survival curves. RESULTS: The mean age was 71.2 years, with 41 female and 35 male patients. Mean tumor size was 5.4 cm with tumor grades of 19 well, 52 moderate, and 5 poorly differentiated. Tumors expressing bcl-2 had a similar DFS (P = .14) but a significantly improved OS (P = .04) compared with the bcl-2 negative tumors. The risk ratio for DFS was 0.49 (95% CI, 0.19-1.26) and for OS was 0.35 (95% CI, 0.13-0.94). CONCLUSIONS: These data indicate that enhanced bcl-2 expression, specifically in Dukes' B colon carcinomas, is associated with improved survival. Thus, patients whose tumors do not express bcl-2 should be considered for adjuvant therapy.


Asunto(s)
Biomarcadores de Tumor/análisis , Neoplasias del Colon/mortalidad , Proteínas Proto-Oncogénicas c-bcl-2/análisis , Adulto , Anciano , Apoptosis , Biomarcadores de Tumor/metabolismo , Neoplasias del Colon/química , Neoplasias del Colon/patología , Femenino , Humanos , Técnicas para Inmunoenzimas , Masculino , Persona de Mediana Edad , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Estadística como Asunto , Análisis de Supervivencia
11.
Can J Surg ; 44(6): 428-31, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11764875

RESUMEN

OBJECTIVE: To determine the effectiveness of sentinel lymph-node (SLN) biopsy for melanoma of the trunk and extremities. DESIGN: Case series review. SETTING: Royal Victoria Hospital, a Canadian university hospital. PATIENTS: Thirty-six patients (18 women and 18 men) seen between October 1996 and December 1998 with melanoma 1 mm or more in thickness with clinically negative lymph-node basins. Follow-up was 396 days. INTERVENTIONS: SLN biopsy. Technetium-99m filtered sulfur colloid (0.5 mCi) was injected intradermally around the melanoma or the excision scar 10 to 15 minutes before the surgical skin preparation. The identification of the SLN(s) was done with a hand-held gamma probe. Local anesthesia was used mostly for inguinal SLN biopsy whereas general anesthesia was usually required for axillary SLN biopsy. Preoperative lymphoscintigraphy was used only for trunk melanomas. OUTCOME MEASURES: Morbidity, successful identification of the sentinel node and locoregional recurrence. RESULTS: The mean age of patients at diagnosis was 53.4 years (range from 22-76 yr). The melanomas were distributed between the lower extremities (20 patients), upper extremities (8 patients) and trunk (8 patients). The mean Breslow thickness was 2.35 mm (range from 1-8 mm). Lymphoscintigraphy accurately localized the lymph-node drainage basin for trunk melanomas. In 1 patient the SLN could not be identified because the radiocolloid failed to migrate (failure rate 2.8%). The average number of SLNs removed was 1.97. Eight patients (22%) had sentinel nodes positive for malignant disease. The postoperative complication rate was 8.5%. Seven of 8 patients with positive SLNs underwent a complete node dissection (1 patient refused). Of the completion dissections only 2 patients had positive non-SLNs. All patients with positive nodes received interferon alpha-2b as adjuvant treatment. At follow-up, 34 patients are alive with no evidence of disease, 1 patient with a positive SLN is alive with distant metastatic disease and 1 patient with a negative SLN is dead of disseminated disease. CONCLUSION: SLN biopsy is a feasible technique with an acceptable failure rate and is thus a useful tool in the surgical management of melanoma.


Asunto(s)
Melanoma/patología , Biopsia del Ganglio Linfático Centinela , Neoplasias Cutáneas/patología , Adulto , Anciano , Femenino , Humanos , Ganglios Linfáticos/diagnóstico por imagen , Metástasis Linfática , Masculino , Persona de Mediana Edad , Cintigrafía , Radiofármacos , Biopsia del Ganglio Linfático Centinela/efectos adversos , Azufre Coloidal Tecnecio Tc 99m
12.
J Surg Res ; 92(2): 201-5, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10896822

RESUMEN

BACKGROUND: Diets rich in omega-3 fatty acids have been shown to decrease both the initiation and promotion of colon carcinogenesis although their effect on hepatic metastasis formation is less well understood. Since adhesion of human colorectal carcinoma (HCRC) cells to hepatic endothelial cells is an important step in the metastatic cascade, the effect of membrane omega-3 fatty acid alterations on endothelial cell adhesion was studied. MATERIALS AND METHODS: CX-1 cells, a moderately differentiated HCRC cell line known to produce hepatic metastases in an athymic mouse intrasplenic injection model, were used. Cells were grown in omega-3 fatty acid-enriched medium and membrane-free fatty acid modifications confirmed with gas chromatography. Both human umbilical vein and hepatic sinusoidal endothelial cells were used in the binding assays. Adhesion assays were performed in a standard fashion using (51)Cr-labeled cells to tumor necrosis factor (TNF)-stimulated endothelial cell monolayers. Immunohistochemical analysis was performed for sialyl-Lewis(x), the receptor involved in endothelial adhesion on the surface of control and fatty acid-modified cells. RESULTS: Gas chromatographic analysis confirmed membrane fatty acid modification of CX-1 cells by growth in docosahexanoic acid (omega-3) (4.761 nmol/10(6) cells vs 0.057 nmol/10(6) cells for controls). Binding of CX-1 to both human umbilical vein and hepatic sinusoidal endothelial cells decreased from 38.4 +/- 0.44 to 11.58 +/- 0.87% (P < 0.01). Immunocytochemical analysis showed a decrease in sialyl-Lewis(x) expression with omega-3 treatment. CONCLUSIONS: These data indicate that omega-3 fatty acids may also be protective against the formation of hepatic metastases. The mechanism for this may be decreased endothelial cell adhesion which in turn may be due to decreased expression of the endothelial receptor sialyl-Lewis(x).


Asunto(s)
Adhesión Celular/efectos de los fármacos , Neoplasias Colorrectales/fisiopatología , Endotelio Vascular/fisiología , Ácidos Grasos Omega-3/farmacología , Animales , Adhesión Celular/fisiología , Cromatografía de Gases , Neoplasias Colorrectales/patología , Ácidos Docosahexaenoicos/farmacología , Endotelio Vascular/efectos de los fármacos , Humanos , Ratones , Ratones Desnudos , Oligosacáridos/análisis , Antígeno Sialil Lewis X , Células Tumorales Cultivadas , Venas Umbilicales
13.
Can J Surg ; 43(1): 29-34, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10714254

RESUMEN

OBJECTIVE: To determine the prognostic value of flow cytometric analysis (S-phase fraction and DNA index) performed on lymph-node metastases of patients with stage III melanoma. DESIGN: A retrospective chart review with flow cytometric analysis of paraffin-embedded tissues. SETTING: A university teaching hospital. PATIENTS: Among 332 patients with cutaneous melanoma, 33 with stage III were identified. Distant metastases developed in 16 patients; 17 had no further recurrence. Charts were reviewed to obtain clinicopathologic parameters such as sex, age, location of the primary tumour, histologic features, presence or absence of ulceration, and Clark's and Breslow's levels. INTERVENTION: DNA ploidy and S-phase fraction were determined on the paraffin-embedded nodes. MAIN OUTCOME MEASURES: The groups with or without recurrence were compared in terms of disease-free survival (DFS) and overall survival (OS). These survival parameters were correlated with DNA ploidy and S-phase fraction. RESULTS: By univariate analysis, clinicopathologic factors did not predict OS. A higher Clark's level of invasion and more than 3 positive lymph nodes were associated with shorter DFS (p < 0.05). Tumour thickness and S-phase fraction did not correlate with either DFS or OS. Patients with diploid lymph-node metastases had an 87% 12-month survival compared with 41% for those with aneuploid tumours. CONCLUSIONS: DNA ploidy may be used as a prognostic index in patients with lymph-node metastases. This could be particularly useful in the context of sentinel lymph-node mapping by which more patients are being identified with single microscopic lymph-node involvement.


Asunto(s)
ADN de Neoplasias/genética , Citometría de Flujo/métodos , Melanoma/patología , Recurrencia Local de Neoplasia/patología , Estadificación de Neoplasias/métodos , Ploidias , Fase S/genética , Neoplasias Cutáneas/patología , Análisis de Varianza , Supervivencia sin Enfermedad , Femenino , Humanos , Escisión del Ganglio Linfático , Metástasis Linfática , Masculino , Melanoma/clasificación , Melanoma/mortalidad , Melanoma/terapia , Persona de Mediana Edad , Pronóstico , Modelos de Riesgos Proporcionales , Reproducibilidad de los Resultados , Estudios Retrospectivos , Factores de Riesgo , Neoplasias Cutáneas/clasificación , Neoplasias Cutáneas/mortalidad , Neoplasias Cutáneas/terapia
14.
Int J Surg Investig ; 2(4): 253-7, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-12678526

RESUMEN

The Fas/Fas ligand pathway may play an important role in the pathogenesis of colorectal carcinoma by allowing tumor cells to evade host immune defenses. Since dietary fats, in particular omega-6 fatty acids, facilitate tumor development their influence on the Fas/Fas ligand pathway needs to be elucidated. The purpose of this study was to determine the effect of membrane free fatty acid (FFA) alterations on Fas expression and sensitivity. Two human colorectal carcinoma cell lines (CX-1 and CCL-188) were grown in cell culture media supplemented with omega-3 (docosahexanoic acid) and omega-6 (linoleic acid) fatty acids. Membrane alterations were confirmed by gas chromatography (GC). Cell surface Fas expression was determined with flow cytometry using an anti-Fas monoclonal antibody. Sensitivity to Fas mediated apoptosis was measured by now cytometric measurement of fragmented DNA stained with propidium iodide. Appropriate changes in the membrane FFA composition were found by GC. Cell surface Fas expression was unaffected in either cell line. Omega-3 fatty acids did not alter Fas sensitivity for either cell line compared to control (CX-1: 59.7%, +/- 5.4 vs 51.4% +/- 7.1 for control, CCL-188: 54.3% +/- 8.6 vs 51.2% +/- 4.8 for control). Omega-6 fatty acids produced a significant decrease in Fas-mediated apoptosis (CX-1: 34.2% +/- 4.8 and CCL-188: 22% +/- 6.0, p < 0.05 vs control). These data indicate that although membrane FFA alterations did not affect Fas expression, omega-6 fatty acids significantly decreased Fas-mediated apoptosis. This inhibitory effect may protect colorectal carcinoma cells from lymphocyte Fas-mediated cell death.


Asunto(s)
Apoptosis , Grasas Insaturadas en la Dieta/farmacología , Ácidos Grasos Insaturados/farmacología , Vigilancia Inmunológica , Receptor fas/fisiología , Neoplasias Colorrectales/patología , Ácidos Grasos Omega-6 , Humanos , Células Tumorales Cultivadas
16.
Cancer Res ; 59(6): 1356-61, 1999 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-10096570

RESUMEN

The cytokine-inducible endothelial cell adhesion receptor E-selectin has been implicated in cancer metastasis. Previously, we reported that experimental liver metastasis of Lewis lung carcinoma subline H-59 cells could be abrogated in animals treated with an anti-E-selectin antibody. To gain further insight into the functional relevance of E-selectin expression to liver colonization, we investigated here the time course of cytokine and hepatic E-selectin expression after the intrasplenic/portal inoculation of H-59 cells by using a combination of reverse transcription-PCR, Northern blot analysis, immunohistochemistry, and in situ hybridization. In parallel, we analyzed cytokine induction in response to the injection of Lewis lung carcinoma subline M-27 and murine melanoma B16-F1 cells, which do not spontaneously metastasize to the liver. In livers derived from normal or saline-injected mice, only minimal basal levels of TNF-alpha and IL-1 mRNA were detectable by RT-PCR. Rapid cytokine mRNA induction was noted within 30-60 min of H-59 injection, reaching maximal levels at 4-6 h. This was followed by the appearance of E-selectin mRNA, which was detectable at 2 h after injection and reached maximal levels at 6-8 h, declining to basal levels by 24 h. In situ hybridization analysis and immunohistochemistry localized E-selectin mRNA and protein, respectively, to the sinusoidal endothelium. M-27 cells failed to induce cytokine or E-selectin expression, whereas B-16 cells elicited a delayed and more short-lived response. The results demonstrate that upon entry into the hepatic circulation, tumor cells can rapidly trigger a molecular cascade leading to the induction of E-selectin expression on the sinusoidal endothelium and suggest that E-selectin induction may contribute to the liver-colonizing potential of tumor cells.


Asunto(s)
Citocinas/biosíntesis , Selectina E/biosíntesis , Neoplasias Hepáticas Experimentales/metabolismo , Animales , Carcinoma Pulmonar de Lewis/patología , Carcinoma Pulmonar de Lewis/secundario , Endotelio/metabolismo , Inmunohistoquímica , Hibridación in Situ , Interleucina-1/biosíntesis , Neoplasias Hepáticas Experimentales/patología , Neoplasias Hepáticas Experimentales/secundario , Melanoma Experimental/patología , Melanoma Experimental/secundario , Ratones , Metástasis de la Neoplasia , Trasplante de Neoplasias , ARN Mensajero/biosíntesis , Células Tumorales Cultivadas , Factor de Necrosis Tumoral alfa/biosíntesis
17.
Blood ; 91(10): 3862-74, 1998 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-9573024

RESUMEN

Exfoliation of plasma membrane components is a directed process that consumes energy and requires active cell metabolism. Proteins involved in regulating the survival and proliferation of eukaryotic cells are released on exfoliated vesicles. We examine here whether the Fas receptor and its cognate ligand (FasL) are present on vesicles shed from high metastatic potential CX-1 cells and low metastatic potential MIP-101 cells and from HuT 78 cells, respectively. Rates of exfoliation at 2 hours and cumulative levels of extracellular vesicles in serum-free medium conditioned by CX-1 cells are increased by 1.8-fold and 1.6-fold, respectively, relative to that in medium conditioned by MIP-101 cells. Although vesicles shed from both cancer cell lines contain Fas antigen, the amount of Fas per vesicle and the percentage of vesicles containing Fas are increased for vesicles isolated from MIP-101 cells, relative to those from CX-1 cells, as determined by immunogold particle labeling and electron microscopy and by immunofluorescence microscopy and flow cytometry. Results of metabolic labeling with 35S-methionine indicate that Fas biosynthesis is reduced by up to 3.3-fold for CX-1 cells, relative to that of MIP-101 cells, consistent with the finding of decreased Fas on vesicles shed from the plasma membrane of CX-1 cells. Although mRNA for soluble Fas receptor is detectable in both cell lines, depletion of shed vesicles from serum-free medium by ultracentrifugation removes all detectable biological activity. FasL is detected on vesicles exfoliated from HuT 78 cells by immunoelectron microscopy and Western blot analysis. FasL-bearing vesicles induce apoptosis of Fas-expressing cancer cells at the same level as observed by treatment with monoclonal anti-Fas antibody. Furthermore, Fas-bearing extracellular vesicles from MIP-101 but not from CX-1 cells protect the CX-1 cell line from FasL-induced and anti-Fas-mediated apoptosis, indicating that Fas present on shed vesicles is biologically active. We conclude that the Fas antigen and its cognate ligand are exfoliated from the cell surface in a bioactive configuration. Exfoliation may provide a mechanism for long-range signal-directed apoptosis while maintaining Fas/FasL on a membrane surface.


Asunto(s)
Adenocarcinoma/metabolismo , Membrana Celular/metabolismo , Neoplasias Colorrectales/metabolismo , Glicoproteínas de Membrana/biosíntesis , Proteínas de Neoplasias/biosíntesis , Receptor fas/biosíntesis , Adenocarcinoma/patología , Apoptosis , Membrana Celular/ultraestructura , Neoplasias Colorrectales/patología , Medios de Cultivo Condicionados , Medio de Cultivo Libre de Suero , Proteína Ligando Fas , Citometría de Flujo , Humanos , Microscopía Electrónica , Microscopía Fluorescente , Metástasis de la Neoplasia , Reacción en Cadena de la Polimerasa , ARN Mensajero/biosíntesis , ARN Neoplásico/biosíntesis , Células Tumorales Cultivadas
20.
Int J Cancer ; 71(4): 612-9, 1997 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-9178816

RESUMEN

E-selectin is a cytokine-inducible endothelial cell adhesion receptor which is involved in the process of leukocyte rolling, the first in a cascade of interactions leading to leukocyte transmigration. Several studies have implicated this receptor in carcinoma cell adhesion to the endothelium, an interaction thought to be required for tumor extravasation during metastasis. To study the role of this receptor in the process of metastasis, we utilized a murine carcinoma line H-59 which is highly metastatic to the liver in vivo. When adhesion of H-59 cells to primary cultures of murine hepatic endothelial cells was measured, it was found that the tumor cells had a low basal level of adhesion to the sinusoidal endothelial cells, which could be significantly and specifically augmented by pre-activation of the endothelial cells with rTNF alpha. This incremental increase in adhesion to the activated endothelium could be completely and specifically abolished by a neutralizing monoclonal antibody to murine E-selectin (MAb 9A9). Similar results were obtained with 2 highly metastatic human colorectal carcinoma lines, HM 7 and CX-1, but not with a second murine subline, M-27, which is poorly metastatic to the liver. To assess the role of E-selectin in metastasis to the liver in vivo, the effect of MAb 9A9 on experimental liver metastasis was evaluated using the syngeneic H-59 model. We show here that this antibody caused a marked, specific and Fc-independent inhibition of experimental liver metastasis, reducing the median number of metastases by 97% relative to the control groups. Our results provide evidence that endothelial E-selectin is a mediator of carcinoma metastasis to the liver.


Asunto(s)
Carcinoma Pulmonar de Lewis/secundario , Neoplasias Colorrectales/patología , Selectina E/fisiología , Endotelio Vascular/química , Neoplasias Hepáticas Experimentales/secundario , Hígado/metabolismo , Animales , Adhesión Celular/efectos de los fármacos , Selectina E/aislamiento & purificación , Endotelio Vascular/efectos de los fármacos , Humanos , Ratones , Proteínas Recombinantes/farmacología , Factor de Necrosis Tumoral alfa/farmacología
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