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1.
J Clin Oncol ; 39(27): 3056-3082, 2021 09 20.
Artículo en Inglés | MEDLINE | ID: mdl-34279999

RESUMEN

PURPOSE: To provide recommendations on the best strategies for the management and on the best timing and treatment (surgical and radiotherapeutic) of the axilla for patients with early-stage breast cancer. METHODS: Ontario Health (Cancer Care Ontario) and ASCO convened a Working Group and Expert Panel to develop evidence-based recommendations informed by a systematic review of the literature. RESULTS: This guideline endorsed two recommendations of the ASCO 2017 guideline for the use of sentinel lymph node biopsy in patients with early-stage breast cancer and expanded on that guideline with recommendations for radiotherapy interventions, timing of staging after neoadjuvant chemotherapy (NAC), and mapping modalities. Overall, the ASCO 2017 guideline, seven high-quality systematic reviews, 54 unique studies, and 65 corollary trials formed the evidentiary basis of this guideline. RECOMMENDATIONS: Recommendations are issued for each of the objectives of this guideline: (1) To determine which patients with early-stage breast cancer require axillary staging, (2) to determine whether any further axillary treatment is indicated for women with early-stage breast cancer who did not receive NAC and are sentinel lymph node-negative at diagnosis, (3) to determine which axillary strategy is indicated for women with early-stage breast cancer who did not receive NAC and are pathologically sentinel lymph node-positive at diagnosis (after a clinically node-negative presentation), (4) to determine what axillary treatment is indicated and what the best timing of axillary treatment for women with early-stage breast cancer is when NAC is used, and (5) to determine which are the best methods for identifying sentinel nodes.Additional information is available at www.asco.org/breast-cancer-guidelines.


Asunto(s)
Axila/patología , Neoplasias de la Mama/complicaciones , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/patología , Canadá , Femenino , Guías como Asunto , Humanos , Ontario
2.
FASEB J ; 34(4): 5106-5127, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32068312

RESUMEN

Excessive proliferation and apoptosis-resistance are hallmarks of cancer. Increased dynamin-related protein 1 (Drp1)-mediated mitochondrial fission is one of the mediators of this phenotype. Mitochondrial fission that accompanies the nuclear division is called mitotic fission and occurs when activated Drp1 binds partner proteins on the outer mitochondrial membrane. We examine the role of Drp1-binding partners, mitochondrial dynamics protein of 49 and 51 kDa (MiD49 and MiD51), as drivers of cell proliferation and apoptosis-resistance in non-small cell lung cancer (NSCLC) and invasive breast carcinoma (IBC). We also evaluate whether inhibiting MiDs can be therapeutically exploited to regress cancer. We show that MiD levels are pathologically elevated in NSCLC and IBC by an epigenetic mechanism (decreased microRNA-34a-3p expression). MiDs silencing causes cell cycle arrest through (a) increased expression of cell cycle inhibitors, p27Kip1 and p21Waf1 , (b) inhibition of Drp1, and (c) inhibition of the Akt-mTOR-p70S6K pathway. Silencing MiDs leads to mitochondrial fusion, cell cycle arrest, increased apoptosis, and tumor regression in a xenotransplant NSCLC model. There are positive correlations between MiD expression and tumor size and grade in breast cancer patients and inverse correlations with survival in NSCLC patients. The microRNA-34a-3p-MiDs axis is important to cancer pathogenesis and constitutes a new therapeutic target.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/patología , Ciclo Celular , Epigénesis Genética , Neoplasias Pulmonares/patología , Proteínas Mitocondriales/metabolismo , Factores de Elongación de Péptidos/metabolismo , Animales , Apoptosis , Biomarcadores de Tumor/genética , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/terapia , Proliferación Celular , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/terapia , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Persona de Mediana Edad , Dinámicas Mitocondriales , Proteínas Mitocondriales/antagonistas & inhibidores , Proteínas Mitocondriales/genética , Factores de Elongación de Péptidos/antagonistas & inhibidores , Factores de Elongación de Péptidos/genética , Pronóstico , Tasa de Supervivencia , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto
3.
FASEB J ; : fj201800120R, 2018 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-29812973

RESUMEN

Triple-negative breast cancers (TNBCs) account for ∼25% of all invasive carcinomas and represent a large subset of aggressive, high-grade tumors. Despite current research focused on understanding the genetic landscape of TNBCs, reliable prognostic and predictive biomarkers remain limited. Although dysregulated microRNAs (miRNAs) have emerged as key players in many cancer types, the role of miRNAs in TNBC disease progression is unclear. We performed miRNA profiling of 51 TNBCs by next-generation sequencing to reveal differentially expressed miRNAs. A total of 228 miRNAs were identified. Three miRNAs (miR-224-5p, miR-375, and miR-205-5p) separated the tumors based on basal status. Six miRNAs (high let-7d-3p, miR-203b-5p, and miR-324-5p; low miR-30a-3p, miR-30a-5p, and miR-199a-5p) were significantly associated with decreased overall survival (OS) and 5 miRNAs (high let-7d-3p; low miR-30a-3p, miR-30a-5p, miR-30c-5p, and miR-128-3p) with decreased relapse-free survival (RFS). On multivariate analysis, high expression of let-7d-3p and low expression of miR-30a were independent predictors of decreased OS and RFS. High expression of miR-95-3p was significantly associated with decreased OS and RFS in patients treated with anthracycline-based chemotherapy. Five miRNAs (let-7d-3p, miR-30a-3p, miR-30c-5p, miR-128-3p, and miR-95-3p) were validated by quantitative RT-PCR. Our findings unveil novel prognostic and predictive miRNA targets for TNBC, including a miRNA signature that predicts patient response to anthracycline-based chemotherapy. This may improve clinical management and/or lead to the development of novel therapies.-Turashvili, G., Lightbody, E. D., Tyryshkin, K., SenGupta, S. K., Elliott, B. E., Madarnas, Y., Ghaffari, A., Day, A., Nicol, C. J. B. Novel prognostic and predictive microRNA targets for triple-negative breast cancer.

4.
Breast Cancer Res Treat ; 165(1): 201-213, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28589367

RESUMEN

PURPOSE: To assess the relationship of moderate-to-vigorous physical activity (MVPA) in leisure-time, household, and occupational domains across the total lifetime and in four age periods with breast cancer risk, as defined by estrogen receptor (ER)/progesterone receptor (PR) status and ER/PR/human epidermal growth factor-2 (HER2) status, among post-menopausal women. METHODS: Data were from 692 women with incident breast cancer and 644 controls in the Canadian Breast Cancer Study, a case-control study of women aged 40-80 years in British Columbia and Ontario. Mean metabolic equivalent (MET)-hours/week for questionnaire-assessed leisure-time, household, and occupational MVPA were calculated for the total lifetime and four age periods (12-17, 18-34, 45-49, and ≥50 years). Odds ratios (ORs) for the relationships between domain-specific MVPA at each lifetime period and risks of ER/PR-defined and ER/PR/HER2-defined breast cancers were estimated using polytomous logistic regression. Trend tests for dose-response relationships were calculated for the ORs across increasing tertiles of mean MET-hours/week of MVPA. RESULTS: Total lifetime leisure-time MVPA was associated with reduced risk of ER-/PR- breast cancer in a dose-response fashion (p trend = 0.014). In contrast, total lifetime household MVPA was associated with reduced risk of ER+ and/or PR+ breast cancer (p trend < 0.001). When further stratified by HER2 status, the effect of leisure-time MVPA appeared confined to HER2- breast cancers, and the effect of household MVPA did not differ according to HER2 status. Similar trends were observed when stratified by age period. CONCLUSIONS: Lifetime leisure-time MVPA appeared to be associated with reduced risk of ER-/PR-/HER2- breast cancers and lifetime household MVPA was associated with reduced risk of ER+ and/or PR+ breast cancer, regardless of HER2 status.


Asunto(s)
Ejercicio Físico , Estilo de Vida Saludable , Posmenopausia , Conducta de Reducción del Riesgo , Neoplasias de la Mama Triple Negativas/prevención & control , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Colombia Británica/epidemiología , Estudios de Casos y Controles , Femenino , Tareas del Hogar , Humanos , Perfil Laboral , Actividades Recreativas , Modelos Logísticos , Persona de Mediana Edad , Análisis Multivariante , Oportunidad Relativa , Ontario/epidemiología , Pronóstico , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Neoplasias de la Mama Triple Negativas/química , Neoplasias de la Mama Triple Negativas/epidemiología
5.
Front Oncol ; 6: 136, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27376028

RESUMEN

Genetic variants of insulin-like growth factor 1 (IGF1) pathway genes have been shown to be associated with breast density and IGF1 levels and, therefore, may also influence breast cancer risk via pro-survival signaling cascades. The aim of this study was to investigate associations between IGF1 pathway single nucleotide polymorphisms (SNPs) and breast cancer risk among European and East Asian women, and potential interactions with menopausal status and breast tumor subtype. Stratified analyses of 1,037 cases and 1,050 controls from a population-based case-control study were conducted to assess associations with breast cancer for 22 SNPs across 5 IGF1 pathway genes in European and East Asian women. Odds ratios were calculated using logistic regression in additive genetic models. Polytomous logistic regression was used to assess heterogeneity by breast tumor subtype. Two SNPs of the IGF1 gene (rs1019731 and rs12821878) were associated with breast cancer risk among European women. Four highly linked IGF1 SNPs (rs2288378, rs17727841, rs7136446, and rs7956547) were modified by menopausal status among East Asian women only and associated with postmenopausal breast cancers. The association between rs2288378 and breast cancer risk was also modified by breast tumor subtype among East Asian women. Several IGF1 polymorphisms were found to be associated with breast cancer risk and some of these associations were modified by menopausal status or breast tumor subtype. Such interactions should be considered when assessing the role of these variants in breast cancer etiology.

6.
Tumour Biol ; 37(5): 6379-87, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26631034

RESUMEN

Studies of vitamin D-related genetic variants and breast cancer have been inconsistent. This study aimed to investigate associations of vitamin D-related polymorphisms and breast cancer risk among European and East Asian women and potential interactions with menopausal status and breast tumour subtypes. Data from a case-control study of breast cancer (1037 cases and 1050 controls) were used to assess relationships between 21 polymorphisms in two vitamin D-related genes (GC and VDR) and breast cancer risk. Odds ratios were calculated in stratified analyses of European and East Asian women, using logistic regression in an additive genetic model. An interaction term was used to explore modification by menopausal status. Polytomous regression was used to assess heterogeneity by breast tumour subtype. False discovery rate adjustments were conducted to account for multiple testing. No association was observed between GC or VDR polymorphisms and breast cancer risk. Modification of these relationships by menopausal status was observed for select polymorphisms in both Europeans (VDR rs4328262 and rs11168292) and East Asians (GC rs7041 and VDR rs11168287). Heterogeneity by tumour subtype was seen for three VDR polymorphisms (rs1544410, rs7967152 and rs2239186) among Europeans, in which associations with ER-/PR-/HER2+ tumours, but not with other subtypes, were observed. In conclusion, associations between vitamin D-related genetic variants and breast cancer were not observed overall, although the relationships between vitamin D pathway polymorphisms and breast cancer may be modified by menopausal status and breast tumour subtype.


Asunto(s)
Neoplasias de la Mama/genética , Receptores de Calcitriol/genética , Proteína de Unión a Vitamina D/genética , Vitamina D/genética , Adulto , Anciano , Pueblo Asiatico/genética , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/patología , Femenino , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Factores de Riesgo , Vitamina D/metabolismo , Población Blanca/genética
7.
Oman Med J ; 30(5): 320-5, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26421111

RESUMEN

OBJECTIVE: Induction of labor (IOL), using intravenous oxytocin, is the artificial initiation of labor before its spontaneous onset for the purpose of delivery of the fetoplacental unit. Although there are various studies looking at dosages of oxytocin, only a few have addressed the issue of discontinuation of oxytocin in the active stage of labor. Thus, our study was conducted to evaluate the need for continuation versus discontinuation of oxytocin during active labor. METHODS: This prospective, randomized controlled trial included 106 women who needed IOL. Oxytocin infusion was initiated at a rate of 3mIU/min and was incremental until 4-6cm cervical dilation. At this point the patients were randomly assigned into one of two groups. In group one, oxytocin was discontinued, and infusion was continued with 0.9% sodium chloride solution. In group two, oxytocin was continued at the same dose until delivery. RESULTS: The duration of oxytocin infusion was 5.5 hours in the oxytocin discontinuation group and 11.0 hours in oxytocin continuation group (p<0.001). The total dose of oxytocin was significantly higher in group two (6.1 units vs. 16.5 units; p=<0.001). The induction-delivery interval was significantly less in group one (9.1 and 11.2 hours in group one and group two, respectively; p=0.023). CONCLUSION: Oxytocin discontinuation in the active stage of labor did not prolong the active stage. The total duration of labor and total oxytocin dose were significantly less in the oxytocin discontinuation group. Our results suggest that oxytocin discontinuation is an alternative and viable option particularly in resource poor and economically challenged settings. It not only reduces the need for intense monitoring and prolonged oxytocin use-associated dangers but reduces the total cost of labor management.

8.
Mol Cancer ; 14: 85, 2015 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-25889730

RESUMEN

BACKGROUND: Among women worldwide, breast cancer is the most commonly diagnosed cancer, and the second leading cause of cancer-related deaths. Improved understanding of breast tumourigenesis may facilitate the development of more effective therapies. Peroxisome proliferator-activated receptor (PPAR)γ is a transcription factor that regulates genes involved in insulin sensitivity and adipogenesis. Previously, we showed, using 7,12-dimethylbenz [a] anthracene (DMBA)-treated haploinsufficient PPARγ mice, that PPARγ suppresses breast tumour progression; however, the PPARγ expressing cell types and mechanisms involved remain to be clarified. Here, the role of PPARγ expression and activation in mammary epithelial cells (MG) with respect to DMBA-mediated breast tumourigenesis was investigated. METHODS: PPARγ MG knockout (PPARγ-MG KO) mice and their congenic, wild-type controls (PPARγ-WT) were treated once a week for six weeks by oral gavage with 1 mg DMBA dissolved in corn oil and maintained on a normal chow diet. At week 7, mice were randomly divided into those maintained on a normal chow diet (DMBA Only; PPARγ-WT: n = 25 and PPARγ-MG KO: n = 39) or those receiving a diet supplemented with the PPARγ ligand, rosiglitazone (ROSI, 4 mg/kg/day) (DMBA + ROSI; PPARγ-WT: n = 34 and PPARγ-MG KO: n = 17) for the duration of the 25-week study. RESULTS: Compared to DMBA Only-treated PPARγ-WTs, both breast tumour susceptibility and serum levels of proinflammatory and chemotactic cytokines, namely IL-4, eotaxin, GM-CSF, IFN-γ, and MIP-1α, were decreased among PPARγ-MG KOs. Cotreatment with ROSI significantly reduced breast tumour progression among PPARγ-WTs, correlating with increased BRCA1 and decreased VEGF and COX-2 protein expression levels in breast tumours; whereas, surprisingly DMBA + ROSI-treated PPARγ-MG KOs showed increased breast tumourigenesis, correlating with activation of COX-2. CONCLUSION: These novel data suggest MG-specific PPARγ expression and signaling is critical during breast tumourigenesis, and may serve as a strong candidate predictive biomarker for response of breast cancer patients to the use of therapeutic strategies that include PPARγ ligands.


Asunto(s)
Progresión de la Enfermedad , Células Epiteliales/metabolismo , Glándulas Mamarias Animales/metabolismo , Neoplasias Mamarias Animales/metabolismo , Neoplasias Mamarias Experimentales/metabolismo , PPAR gamma/metabolismo , Transducción de Señal , 9,10-Dimetil-1,2-benzantraceno , Animales , Proteína BRCA1/metabolismo , Citocinas/sangre , Células Epiteliales/patología , Femenino , Eliminación de Gen , Glándulas Mamarias Animales/patología , Neoplasias Mamarias Animales/sangre , Neoplasias Mamarias Animales/patología , Neoplasias Mamarias Experimentales/sangre , Neoplasias Mamarias Experimentales/patología , Ratones Noqueados , Modelos Biológicos , Especificidad de Órganos , Carga Tumoral
9.
Mol Cancer Res ; 13(6): 1044-55, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25784716

RESUMEN

UNLABELLED: Triple-negative breast cancers (TNBCs) are highly aggressive cancers that lack targeted therapies. However, EGFR is frequently activated in a subset of TNBCs and represents a viable clinical target. Because the endocytic adaptor protein Endophilin A2 (SH3GL1/Endo II) has been implicated in EGFR internalization, we investigated Endo II expression and function in human TNBCs. Endo II expression was high in several TNBC cells compared with normal breast epithelial cells. Stable knockdown (KD) of Endo II was achieved in two TNBC cell lines, and although cell viability was unaffected, defects in receptor-mediated endocytosis were observed. EGFR signaling to Erk and Akt kinases was impaired in Endo II KD cells, and this correlated with reduced rates of EGFR internalization and cell motility. Endo II KD cells also displayed defects in three dimensional (3D) cell invasion, and this correlated with impaired extracellular matrix degradation and internalization of MT1-MMP. Endo II silencing also caused a significant reduction in TNBC tumor growth and lung metastasis in mammary orthotopic tumor xenograft assays. In human breast tumor specimens, Endo II expression was highest in TNBC tumors compared with other subtypes, and at the level of gene expression, high Endo II was associated with reduced relapse-free survival in patients with basal-like breast cancers. Together, these results identify a positive role for Endo II in TNBC tumor metastasis and a potential link with poor prognosis. IMPLICATIONS: Endophilin A2 and related adaptor proteins represent important signaling hubs to target in metastatic cancers.


Asunto(s)
Péptidos y Proteínas de Señalización Intracelular/genética , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Neoplasias Pulmonares/secundario , Neoplasias de la Mama Triple Negativas/patología , Animales , Línea Celular Tumoral , Receptores ErbB/metabolismo , Matriz Extracelular/metabolismo , Técnicas de Silenciamiento del Gen , Xenoinjertos , Humanos , Ratones , Ratones Endogámicos BALB C , Invasividad Neoplásica , Transducción de Señal
10.
J Clin Oncol ; 32(35): 3967-73, 2014 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-25385731

RESUMEN

PURPOSE: Therapies that target overexpression of human epidermal growth factor receptor 2 (HER2) rely on accurate and timely assessment of all patients with new diagnoses. This study examines HER2 testing of primary breast cancer tissue when performed with immunohistochemistry (IHC) and additional in situ hybridization (ISH) for negative cases (IHC 0/1+). The analysis focuses on the rate of false-negative HER2 tests, defined as IHC 0/1+ with an ISH ratio ≥ 2.0, in eight pathology centers across Canada. PATIENTS AND METHODS: Whole sections of surgical resections or tissue microarrays (TMAs) from invasive breast carcinoma tissue were tested by both IHC and ISH using standardized local methods. Samples were scored by the local breast pathologist, and consecutive HER2-negative IHC results (IHC 0/1+) were compared with the corresponding fluorescence or silver ISH result. RESULTS: Overall, 711 surgical excisions of primary breast cancer were analyzed by IHC and ISH; HER2 and chromosome 17 centromere (CEP17) counts were available in all cases. The overall rate of false-negative samples was 0.84% (six of 711 samples). Interpretable IHC and ISH scores were available in 1,212 cases from TMAs, and the overall rate of false-negative cases was 1.6% (16 of 978 cases). CONCLUSION: Our observation confirms that IHC is an adequate test to predict negative HER2 status in primary breast cancer in surgical excision specimens, even when different antibodies and IHC platforms are used. The study supports the American Society of Clinical Oncology/College of American Pathologists and Canadian testing algorithms of using IHC followed by ISH for equivocal cases.


Asunto(s)
Neoplasias de la Mama/metabolismo , Receptor ErbB-2/metabolismo , Biomarcadores de Tumor/metabolismo , Neoplasias de la Mama/cirugía , Canadá , Cromosomas Humanos Par 17/ultraestructura , Reacciones Falso Negativas , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Inmunohistoquímica , Hibridación in Situ , Hibridación Fluorescente in Situ , Estudios Prospectivos , Estudios Retrospectivos , Análisis de Matrices Tisulares
11.
Int J Cancer ; 134(5): 1055-66, 2014 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-23934545

RESUMEN

Breast cancer is the leading cause of new cancer diagnoses among women. Using peroxisome proliferator-activated receptor (PPAR)γ((+/-)) mice, we showed normal expression of PPARγ was critical to stop 7,12-dimethylbenz[a]anthracene (DMBA)-induced breast tumorigenesis. PPARγ is expressed in many breast cell types including mammary secretory epithelial (MSE) cells. MSEs proliferate as required during pregnancy, and undergo apoptosis or reversible transdifferentiation during involution once lactation is complete. Thus, MSE-specific loss of PPARγ was hypothesized to enhance DMBA-mediated breast tumorigenesis. To test this, MSE cell-specific PPARγ knockout (PPARγ-MSE KO) and control (PPARγ-WT) mice were generated, mated and allowed to nurse for three days. One week after involution, dams were treated with DMBA to initiate breast tumors, and randomized on week 7 to continue receiving a normal chow diet (DMBA Only: PPARγ-WT, n = 15; PPARγ-MSE KO, n = 25) or one supplemented with a PPARγ activating drug (DMBA + ROSI: PPARγ-WT, n = 17; PPARγ-MSE KO, n = 24), and monitored for changes in breast tumor outcomes. PPARγ-MSE KOs had significantly lower overall survival and decreased mammary tumor latency as compared to PPARγ-WT controls. PPARγ activation significantly reduced DMBA-mediated malignant mammary tumor volumes irrespective of genotype. MSE-specific PPARγ loss resulted in decreased mammary gland expression of PTEN and Bax, increased superoxide anion production, and elevated serum eotaxin and RANTES, creating a protumorigenic environment. Moreover, PPARγ activation in MSEs delayed mammary tumor growth in part by down-regulating Cox-1, Cox-2 and cyclin D1. Collectively, these studies highlight a protective role of MSE-specific PPARγ during breast tumorigenesis, and support a novel chemotherapeutic role of PPARγ activation in breast cancer.


Asunto(s)
Glándulas Mamarias Animales/metabolismo , Neoplasias Mamarias Experimentales/etiología , PPAR gamma/fisiología , 9,10-Dimetil-1,2-benzantraceno , Animales , Células Epiteliales/metabolismo , Femenino , Neoplasias Mamarias Experimentales/metabolismo , Ratones , Ratones Noqueados , Fosfohidrolasa PTEN/análisis , Proteína X Asociada a bcl-2/análisis
12.
Occup Environ Med ; 70(12): 831-8, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23817841

RESUMEN

OBJECTIVES: Long-term night work has been suggested as a risk factor for breast cancer; however, additional studies with more comprehensive methods of exposure assessment to capture the diversity of shift patterns are needed. As well, few previous studies have considered the role of hormone receptor subtype. METHODS: Relationships between night shift work and breast cancer were examined among 1134 breast cancer cases and 1179 controls, frequency-matched by age in Vancouver, British Columbia, and Kingston, Ontario. Self-reported lifetime occupational histories were assessed for night shift work, and hormone receptor status obtained from tumour pathology records. RESULTS: With approximately one-third of cases and controls ever employed in night shift work, associations with duration demonstrated no relationship between either 0-14 or 15-29 years, while an association was apparent for ≥30 years (OR=2.21, 95% CI 1.14 to 4.31). This association with long-term night shift work is robust to alternative definitions of prolonged shift work, with similar results for both health and non-health care workers. CONCLUSIONS: Long-term night shift work in a diverse mix of occupations is associated with increased breast cancer risk and not limited to nurses, as in most previous studies.


Asunto(s)
Neoplasias de la Mama/etiología , Enfermedades Profesionales/epidemiología , Tolerancia al Trabajo Programado/fisiología , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/metabolismo , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/metabolismo , Colombia Británica/epidemiología , Estudios de Casos y Controles , Femenino , Humanos , Menopausia , Persona de Mediana Edad , Ontario/epidemiología , Receptores de Estrógenos/metabolismo , Receptores de Progesterona/metabolismo , Factores de Riesgo , Adulto Joven
13.
Carcinogenesis ; 33(7): 1412-20, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22581835

RESUMEN

Peroxisome proliferator-activated receptor (PPAR)γ regulates the expression of genes essential for fat storage, primarily through its activity in adipocytes. It also has a role in carcinogenesis. PPARγ normally stops the in vivo progression of 7,12-dimethylbenz[a]anthracene (DMBA)-mediated breast tumours as revealed with PPARγ haploinsufficient mice. Since many cell types associated with the mammary gland express PPARγ, each with unique signal patterns, this study aimed to define which tissues are required for PPARγ-dependent antitumour effects. Accordingly, adipocyte-specific PPARγ knockout (PPARγ-A KO) mice and their wild-type (PPARγ-WT) controls were generated, and treated with DMBA for 6 weeks to initiate breast tumorigenesis. On week 7, mice were randomized to continue on normal chow diet or one supplemented with rosiglitazone (ROSI), and followed for 25 weeks for tumour outcomes. In PPARγ-A KO versus PPARγ-WT mice, malignant mammary tumour incidence was significantly higher and mammary tumour latency was decreased. DMBA + ROSI treatment reduced average mammary tumour volumes by 50%. Gene expression analyses of mammary glands by quantitative real-time polymerase chain reaction and immunofluorescence indicated that untreated PPARγ-A KOs had significantly decreased BRCA1 expression in mammary stromal adipocytes. Compared with PPARγ-WT mice, serum leptin levels in PPARγ-A KOs were also significantly higher throughout the study. Together, these data are the first to suggest that in vivo PPARγ expression in mammary stromal adipocytes attenuates breast tumorigenesis through BRCA1 upregulation and decreased leptin secretion. This study supports a protective effect of activating PPARγ as a novel chemopreventive therapy for breast cancer.


Asunto(s)
Adipocitos/metabolismo , Neoplasias Mamarias Experimentales/prevención & control , PPAR gamma/fisiología , Células del Estroma/metabolismo , Animales , Secuencia de Bases , Cartilla de ADN , Ensayo de Inmunoadsorción Enzimática , Femenino , Ratones , Ratones Noqueados , PPAR gamma/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Rosiglitazona , Tiazolidinedionas/administración & dosificación
14.
BMC Cancer ; 12: 82, 2012 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-22397367

RESUMEN

BACKGROUND: The membrane cytoskeletal crosslinker, ezrin, a member of the ERM family of proteins, is frequently over-expressed in human breast cancers, and is required for motility and invasion of epithelial cells. Our group previously showed that ezrin acts co-operatively with the non-receptor tyrosine kinase, Src, in deregulation of cell-cell contacts and scattering of epithelial cells. In particular, ezrin phosphorylation on Y477 by Src is specific to ezrin within the ERM family, and is required for HGF-induced scattering of epithelial cells. We therefore sought to examine the role of Y477 phosphorylation in ezrin on tumor progression. METHODS: Using a highly metastatic mouse mammary carcinoma cell line (AC2M2), we tested the effect of over-expressing a non-phosphorylatable form of ezrin (Y477F) on invasive colony growth in 3-dimensional Matrigel cultures, and on local invasion and metastasis in an orthotopic engraftment model. RESULTS: AC2M2 cells over-expressing Y477F ezrin exhibited delayed migration in vitro, and cohesive round colonies in 3-dimensional Matrigel cultures, compared to control cells that formed invasive colonies with branching chains of cells and numerous actin-rich protrusions. Moreover, over-expression of Y477F ezrin inhibits local tumor invasion in vivo. Whereas orthotopically injected wild type AC2M2 tumor cells were found to infiltrate into the abdominal wall and visceral organs within three weeks, tumors expressing Y477F ezrin remained circumscribed, with little invasion into the surrounding stroma and abdominal wall. Additionally, Y477F ezrin reduces the number of lung metastatic lesions. CONCLUSIONS: Our study implicates a role of Y477 ezrin, which is phosphorylated by Src, in regulating local invasion and metastasis of breast carcinoma cells, and provides a clinically relevant model for assessing the Src/ezrin pathway as a potential prognostic/predictive marker or treatment target for invasive human breast cancer.


Asunto(s)
Neoplasias de la Mama/patología , Carcinoma/patología , Proteínas del Citoesqueleto/fisiología , Animales , Western Blotting , Neoplasias de la Mama/metabolismo , Carcinoma/metabolismo , Movimiento Celular/fisiología , Proteínas del Citoesqueleto/metabolismo , Femenino , Ratones , Ratones Desnudos , Invasividad Neoplásica , Metástasis de la Neoplasia , Fosforilación , Células Tumorales Cultivadas , Tirosina/metabolismo
15.
Cancers (Basel) ; 4(3): 725-42, 2012 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-24213463

RESUMEN

There is critical need for improved biomarker assessment platforms which integrate traditional pathological parameters (TNM stage, grade and ER/PR/HER2 status) with molecular profiling, to better define prognostic subgroups or systemic treatment response. One roadblock is the lack of semi-quantitative methods which reliably measure biomarker expression. Our study assesses reliability of automated immunohistochemistry (IHC) scoring compared to manual scoring of five selected biomarkers in a tissue microarray (TMA) of 63 human breast cancer cases, and correlates these markers with clinico-pathological data. TMA slides were scanned into an Ariol Imaging System, and histologic (H) scores (% positive tumor area x staining intensity 0-3) were calculated using trained algorithms. H scores for all five biomarkers concurred with pathologists' scores, based on Pearson correlation coefficients (0.80-0.90) for continuous data and Kappa statistics (0.55-0.92) for positive vs. negative stain. Using continuous data, significant association of pERK expression with absence of LVI (p = 0.005) and lymph node negativity (p = 0.002) was observed. p53 over-expression, characteristic of dysfunctional p53 in cancer, and Ki67 were associated with high grade (p = 0.032 and 0.0007, respectively). Cyclin D1 correlated inversely with ER/PR/HER2-ve (triple negative) tumors (p = 0.0002). Thus automated quantitation of immunostaining concurs with pathologists' scoring, and provides meaningful associations with clinico-pathological data.

16.
Cancers (Basel) ; 3(4): 4212-27, 2011 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-24213134

RESUMEN

Abnormal cell division leading to the gain or loss of entire chromosomes and consequent genetic instability is a hallmark of cancer. Centromere protein -A (CENPA) is a centromere-specific histone-H3-like variant gene involved in regulating chromosome segregation during cell division. CENPA is one of the genes included in some of the commercially available RNA based prognostic assays for breast cancer (BCa)-the 70 gene signature MammaPrint® and the five gene Molecular Grade Index (MGISM). Our aim was to assess the immunohistochemical (IHC) expression of CENPA in normal and malignant breast tissue. Clinically annotated triplicate core tissue microarrays of 63 invasive BCa and 20 normal breast samples were stained with a monoclonal antibody against CENPA and scored for percentage of visibly stained nuclei. Survival analyses with Kaplan-Meier (KM) estimate and Cox proportional hazards regression models were applied to assess the associations between CENPA expression and disease free survival (DFS). Average percentage of nuclei visibly stained with CENPA antibody was significantly higher (p = 0.02) in BCa than normal tissue. The 3-year DFS in tumors over-expressing CENPA (>50% stained nuclei) was 79% compared to 85% in low expression tumors ( 60.07; p = 0.06) within our small cohort. To the best of our knowledge, this is the first published report evaluating the implications of increased IHC expression of CENPA in paraffin embedded breast tissue samples. Our finding that increased CENPA expression may be associated with shorter DFS in BCa supports its exploration as a potential prognostic biomarker.

17.
Can Urol Assoc J ; 4(2): E39-41, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20368880

RESUMEN

Extra-adrenal myelolipoma is a very rare type of tumour. Laparoscopic removal of extra-adrenal myelolipoma has not been previously reported. We report the first case of laparoscopic excision of a large extra-adrenal perirenal myelolipoma.

18.
Rev Sci Instrum ; 81(3): 034103, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20370198

RESUMEN

Inkjet printed organic thin films are being used for a variety of electronic and sensor applications with advantages that include ease of fabrication and reproducibility. Construction and use of a low-cost photometer based on a light-emitting diode (LED) light source and a photodiode detector are described. The photometer attaches to the exit of the printer with the transparent substrate onto which the film is printed passing between the LED and photodiode. By measuring the output voltage of the detector, the transmittance and absorbance of the inkjet printed film can be calculated in real-time. Since absorbance is linearly proportional to thickness in the Beer-Lambert regime, the thickness of the film may be monitored and controlled by varying the number of passes through the printer. Use of the photometer is demonstrated for inkjet printed films of monolayer-protected colloidal gold nanoparticles that function as chemical vapor sensors. The photometer may find applications in both research and quality control related to the manufacture of organic electronic devices and sensors and enables "feedback-controlled" inkjet printing.


Asunto(s)
Fotometría/instrumentación , Impresión/instrumentación , Absorción , Impedancia Eléctrica , Electrónica/instrumentación , Electrónica/métodos , Diseño de Equipo , Compuestos de Oro , Nanopartículas del Metal , Fotometría/métodos , Impresión/métodos , Factores de Tiempo , Rayos Ultravioleta
19.
Breast J ; 15(4): 409-13, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19601946

RESUMEN

Basaloid carcinomas have been documented in various anatomic locations. We describe a primary invasive adenocarcinoma of the nipple with extensive basaloid features that was also associated with squamous cell carcinoma (SCC) in situ and an aggressive behavior. A 69-year-old woman without a history of breast neoplasia presented with right nipple pain. Biopsy of the nipple revealed SCC in situ. One year later, she returned with nipple ulceration. An excisional specimen showed a 1.7 cm nodule composed of invasive sheets and ribbons of basaloid cells with numerous mitoses, extensive tumor necrosis and evidence of glandular differentiation. SCC in situ was present in the overlying epidermis. The differential diagnosis included a primary basaloid adenocarcinoma of the nipple, basal cell carcinoma of the nipple, neuroendocrine carcinoma, melanoma, basaloid variant of adenoid cystic carcinoma and metastatic disease. Immunohistochemical profile of this tumor supported a primary basaloid adenocarcinoma of the nipple. Although the initial sentinel lymph node biopsy was negative, within a year of diagnosis, the patient developed ipsilateral axillary node and pulmonary metastases. To the best of our knowledge, this is the first case of basaloid carcinoma to be documented in this anatomic site.


Asunto(s)
Carcinoma in Situ/patología , Carcinoma Basocelular/patología , Carcinoma de Células Escamosas/patología , Pezones/patología , Anciano , Antineoplásicos/uso terapéutico , Biopsia , Carcinoma in Situ/complicaciones , Carcinoma in Situ/tratamiento farmacológico , Carcinoma in Situ/cirugía , Carcinoma Basocelular/complicaciones , Carcinoma Basocelular/tratamiento farmacológico , Carcinoma Basocelular/cirugía , Carcinoma de Células Escamosas/complicaciones , Carcinoma de Células Escamosas/tratamiento farmacológico , Carcinoma de Células Escamosas/cirugía , Resultado Fatal , Femenino , Humanos
20.
BMC Cancer ; 8: 130, 2008 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-18466613

RESUMEN

BACKGROUND: Previous studies and biological mechanisms of carcinogenesis suggest that the steroid receptor content of benign breast epithelium may be related to breast cancer risk. The objective in this study was to compare the levels of estrogen receptor-alpha (ER) and progesterone receptor (PR) in nonneoplastic breast epithelium between breast cancer cases and biopsy controls. METHODS: Between 1995 and 1997 at two sites (Women's College Hospital in Toronto and Kingston General Hospital), 667 women who were scheduled for diagnostic excisional breast biopsies completed a questionnaire providing personal information and agreed to allow analysis of routinely resected tissue. Histological slides with nonneoplastic epithelium were available for 101 cancer cases and 200 biopsy controls in Toronto and for 105 cancer cases and 119 controls in Kingston. Nonneoplastic epithelium was examined with immunohistochemical assays to determine the percent of epithelial cells staining for ER and PR. Unconditional logistic regression was used to calculate odds ratios (OR) stratified by study site. RESULTS: The ER content of nonneoplastic tissue was higher in cases than biopsy controls in unadjusted analyses; after adjustment for age, however, a weak association remained in only one of the study sites. After adjustment for age, the PR content of nonneoplastic tissue was slightly lower in breast cancer cases than controls in one study site. Furthermore, this inverse association was confined to women with PR negative breast cancer in comparison to the controls. No interaction between ER and PR content of nonneoplastic tissue was observed in relation to the odds of having breast cancer. CONCLUSION: The results of this study are consistent with only a slight indication of increased ER levels in nonneoplastic tissue in breast cancer cases relative to controls. This study contributes to the understanding of breast cancer by examining both ER and PR in nonneoplastic tissue. Limitations remain, however, such as the necessity of using as controls women with benign breast changes, difficulties in selecting the appropriate tissue for analysis, and tissue sampling concurrent to diagnosis.


Asunto(s)
Glándulas Mamarias Humanas/metabolismo , Receptores de Estrógenos/biosíntesis , Receptores de Progesterona/biosíntesis , Adulto , Anciano , Neoplasias de la Mama/patología , Neoplasias de la Mama/cirugía , Carcinoma/patología , Carcinoma/cirugía , Transformación Celular Neoplásica , Epitelio/metabolismo , Epitelio/patología , Femenino , Humanos , Inmunohistoquímica , Glándulas Mamarias Humanas/patología , Persona de Mediana Edad
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