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1.
Climacteric ; 14(6): 683-8, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21942620

RESUMEN

OBJECTIVE: Nasal administration gives a more acute but shorter rise in serum hormone levels than oral administration and may therefore have less effect on the fibroglandular tissue in the breasts. We studied the change in mammographic breast density after nasal vs. oral administration of postmenopausal hormone therapy (PHT). METHODS: We studied participants in a randomized, controlled trial on the impact of nasal vs. oral administration of PHT (combined 17ß-estradiol plus norethisterone) for 1 year. Two radiologists classified mammographic density at baseline and after 1 year into four categories. Also, the percentage density was calculated by a computer-based method. The main outcome measure was the difference in the proportion of women with an increase in mammographic density category after 1 year between the nasal and oral groups. Also, the change in the percentage density was calculated. RESULTS: The study group comprised 112 healthy postmenopausal women (mean age 56 years), of whom 53 received oral and 59 intranasal PHT. An increase in mammographic density category after 1 year was seen in 20% of the women in the nasal group and in 34% of the oral group. This resulted in a non-significant difference in the proportion of women in whom mammographic breast density had increased by 214% (95% confidence interval (CI) 230% to 2.7%). The mean change in percentage density was 21.2% in the nasal group and + 1.2% in the oral group, yielding a 22.4% differential effect (95% CI 27.3% to 2.5%). CONCLUSIONS: One year of nasal PHT gave a smaller, although not statistically significant, increase in mammographic density than oral PHT. Remaining issues are the relation between the route of administration of PHT and breast complaints and breast cancer risk.


Asunto(s)
Estradiol/administración & dosificación , Terapia de Reemplazo de Estrógeno , Mamografía , Noretindrona/administración & dosificación , Posmenopausia , Administración Intranasal , Administración Oral , Neoplasias de la Mama/prevención & control , Anticonceptivos Sintéticos Orales/administración & dosificación , Método Doble Ciego , Combinación de Medicamentos , Femenino , Humanos , Persona de Mediana Edad
2.
Climacteric ; 13(2): 103-20, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19958161

RESUMEN

BACKGROUND: Female sexual dysfunction (FSD) is a multidimensional problem combining biological, psychological and interpersonal elements of multiple etiologies. Menopause-related sexual dysfunction may not be reversible without therapy. Hormonal deficiency does not usually decrease in severity over time. Many options are available for the successful treatment of postmenopausal FSD. OBJECTIVE: To review the pharmacological and non-pharmacological therapies available for postmenopausal FSD, focusing on practical recommendations for managing postmenopausal women with sexual complaints, through a literature review of the most relevant publications in this field. PSYCHOSOCIAL THERAPY: This type of therapy (basic counselling, physiotherapy and psychosexual intervention) is considered an adaptable step-by-step approach for diagnostic and therapeutic strategies, normally combined with biomedical interventions to provide optimal outcomes. PHARMACOLOGICAL THERAPY: For postmenopausal FSD, many interventional options are now available, including hormonal therapies such as estrogens, testosterone, combined estrogen/testosterone, tibolone and dehydroepiandrosterone. CONCLUSIONS: Menopause and its transition represent significant risk factors for the development of sexual dysfunction. FSD impacts greatly on a patient's quality of life. Consequently, it is receiving more attention thanks to the development of effective treatments. Non-pharmacological approaches should be used first, focusing on lifestyle and psychosexual therapy. If required, proven effective hormonal and non-hormonal therapeutic options are available.


Asunto(s)
Terapia de Reemplazo de Estrógeno , Menopausia/fisiología , Posmenopausia , Disfunciones Sexuales Fisiológicas/terapia , Disfunciones Sexuales Psicológicas/terapia , Femenino , Humanos , Persona de Mediana Edad , Calidad de Vida , Factores de Riesgo , Disfunciones Sexuales Fisiológicas/tratamiento farmacológico , Disfunciones Sexuales Fisiológicas/psicología , Disfunciones Sexuales Psicológicas/tratamiento farmacológico , Disfunciones Sexuales Psicológicas/psicología
3.
Climacteric ; 11 Suppl 1: 22-8, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18464018

RESUMEN

OBJECTIVE: To evaluate the effect of estetrol (E(4)) on vaginal cornification and uterine wet weight in the ovariectomized rat. METHODS: Adult female rats served as experimental animals. Six groups of ovariectomized rats (eight per group) were treated orally once daily for 7 days as follows: vehicle (negative) control; E(4): 0.1, 0.3, 1.0 and 3.0 mg/kg/day, and ethinylestradiol 0.05 mg/kg/day as active (positive) control. Vaginal lavages were obtained daily and uterine wet weight was determined on day 7. RESULTS: Vaginal cornification was observed by day 5 in all rats at all E(4) doses and in the animals receiving ethinylestradiol, but not in the control rats. The onset of cornification with E(4) was dose-dependent. After 7 days' treatment, the two highest E(4) doses (1.0 and 3.0 mg) induced statistically significant higher uterine wet weight compared to vehicle. CONCLUSION: Estetrol has estrogenic effects on the vagina and on the uterus of ovariectomized rats. The potency of E(4) is approximately 20-fold lower compared to ethinylestradiol.


Asunto(s)
Estetrol/farmacología , Ovariectomía , Útero/efectos de los fármacos , Útero/patología , Vagina/efectos de los fármacos , Vagina/patología , Administración Oral , Animales , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Tamaño de los Órganos/efectos de los fármacos , Distribución Aleatoria , Ratas , Irrigación Terapéutica
4.
Maturitas ; 61(1-2): 141-50, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-19434886

RESUMEN

Cancer is a genetic disease. Breast cancer tumorigenesis can be described as a multi-step process in which each step is thought to correlate with one or more distinct mutations in major regulatory genes. The question addressed is how far a multi-step progression model for sporadic breast cancer would differ from that for hereditary breast cancer. Hereditary breast cancer is characterized by an inherited susceptibility to breast cancer on basis of an identified germline mutation in one allele of a high penetrance susceptibility gene (such as BRCA1, BRCA2, CHEK 2, TP53 or PTEN). Inactivation of the second allele of these tumour suppressor genes would be an early event in this oncogenic pathway (Knudson's "two-hit" model). Sporadic breast cancers result from a serial stepwise accumulation of acquired and uncorrected mutations in somatic genes, without any germline mutation playing a role. Mutational activation of oncogenes, often coupled with non-mutational inactivation of tumour suppressor genes, is probably an early event in sporadic tumours, followed by more, independent mutations in at least four or five other genes, the chronological order of which is likely less important. Oncogenes that have been reported to play an early role in sporadic breast cancer are MYC, CCND1 (Cyclin D1) and ERBB2 (HER2/neu). In sporadic breast cancer, mutational inactivation of BRCA1/2 is rare, as inactivation requires both gene copies to be mutated or totally deleted. However, non-mutational functional suppression could result from various mechanisms, such as hypermethylation of the BRCA1 promoter or binding of BRCA2 by EMSY. In sporadic breast tumorigenesis, at least three different pathway-specific mechanisms of tumour progression are recognizable, with breast carcinogenesis being different in ductal versus lobular carcinoma, and in well differentiated versus poorly differentiated ductal cancers. Thus, different breast cancer pathways emerge early in the process of carcinogenesis, ultimately leading to clinically different tumour types. As mutations acquired early during tumorigenesis will be present in all later stages, large-scale gene expression profiling using DNA microarray analysis techniques can help to classify breast cancers into clinically relevant subtypes.

5.
Breast ; 16 Suppl 2: S182-9, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17983942

RESUMEN

Many patients with a history of breast cancer (BC) will suffer from vasomotor symptoms, which can be induced or exacerbated by treatment with tamoxifen or aromatase inhibitors. The LIBERATE trial was designed as a randomized, double-blind, multicenter trial to demonstrate that tibolone 2.5mg/day (Livial) is non-inferior to placebo regarding BC recurrence in women with vasomotor symptoms surgically treated for primary BC within the last 5 years. Secondary objectives are effects on vasomotor symptoms as well as overall survival, bone mineral density and health-related quality of life. Mean age at randomization was 52.6 years, and the mean time since surgery was 2.1 years. The mean daily number of hot flushes and sweating episodes was 7.3 and 6.1, respectively. For the primary tumor, Stage IIA or higher was reported for >70% of the patients. In subjects whose receptor status was known, 78.2% of the tumors were estrogen receptors positive. At randomization, tamoxifen was given to 66.2% of all patients and aromatase inhibitors to 7%. Chemotherapy was reported by 5% at randomization. The adjuvant tamoxifen use in LIBERATE allows a comparison with the Stockholm trial (showing no risk of BC recurrence associated with hormone therapy), which was stopped prematurely subsequent to HABITS. The LIBERATE trial is the largest, ongoing, well-controlled study for treatment of vasomotor symptoms in BC patients.


Asunto(s)
Antineoplásicos Hormonales/farmacología , Enfermedades del Sistema Nervioso Autónomo/tratamiento farmacológico , Neoplasias de la Mama/tratamiento farmacológico , Norpregnenos/farmacología , Sistema Vasomotor/efectos de los fármacos , Antineoplásicos Hormonales/efectos adversos , Antineoplásicos Hormonales/uso terapéutico , Inhibidores de la Aromatasa/efectos adversos , Inhibidores de la Aromatasa/farmacología , Inhibidores de la Aromatasa/uso terapéutico , Enfermedades del Sistema Nervioso Autónomo/inducido químicamente , Densidad Ósea , Método Doble Ciego , Femenino , Humanos , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Estadificación de Neoplasias , Norpregnenos/uso terapéutico , Calidad de Vida , Análisis de Supervivencia , Tamoxifeno/efectos adversos , Tamoxifeno/farmacología , Tamoxifeno/uso terapéutico , Resultado del Tratamiento
6.
Eur J Cancer ; 43(10): 1556-63, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17532207

RESUMEN

INTRODUCTION: Breast cancer patients with early disease and a natural humoral response to MUC1 have a favourable prognosis, suggesting a possible role of MUC1 antibodies (ab) in controlling haematogenous tumour dissemination and outgrowth. The aim of the study was to evaluate humoral immune responses to MUC1 in women at hereditary high risk of breast cancer to investigate whether this immune response could play a role in the prevention of disease. MATERIALS AND METHODS: CA15.3 (U/mL), and IgG and IgM ab to MUC1 (arbitrary units per mL, Arb-U/mL) were measured in serum samples obtained from 422 women at hereditary high risk of breast/ovarian cancer, of whom 127 BRCA1/2 carriers, attending the Familial Cancer Clinic of the VU University Medical Centre, and from 370 age-matched healthy controls. Serum samples obtained from women who developed breast cancer (N=12) or breast cancer recurrence (N=17), and from women who underwent prophylactic mastectomy (N=12) and had no breast lesions were also tested. RESULTS: CA15.3 ranked significantly higher in mutation carriers than in controls (P=0.03). MUC1 IgG ab levels ranked significantly lower in BRCA1/2 mutation carriers than in controls (P=0.003). MUC1 IgG levels were not significantly different (P=0.53) between women who developed primary breast cancer (median 0.72Arb-U/ml, range 0.52-2.44Arb-U/ml) and women who underwent prophylactic mastectomy and had no breast lesions (median 1.04Arb-U/ml, range 0.43-2.88Arb-U/ml). CONCLUSION: Serum levels of natural IgG ab to MUC1 are lower in BRCA1/2 mutation carriers than in healthy controls. Furthermore, in contrast to previous results in women with sporadic breast cancer, no elevated MUC1 IgG ab were seen in women at hereditary high risk who developed breast cancer. Prophylactic immunotherapy with MUC1 substrates may be a strategy to reduce the risk of breast cancer in BRCA1/2 mutation carriers, strengthening tumour immune surveillance.


Asunto(s)
Anticuerpos/inmunología , Neoplasias de la Mama/inmunología , Genes BRCA1 , Genes BRCA2 , Mucina-1/inmunología , Neoplasias Ováricas/inmunología , Adulto , Anciano , Formación de Anticuerpos/genética , Neoplasias de la Mama/genética , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Inmunoglobulina M/inmunología , Persona de Mediana Edad , Mutación/genética , Neoplasias Ováricas/genética
7.
Hum Reprod ; 21(6): 1635-42, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16501036

RESUMEN

BACKGROUND: Inflammation plays an important role in the development of atherosclerotic disease. Oral post-menopausal hormone therapy increases serum C-reactive protein (CRP) levels. This study compared the effects of intranasal and oral administration of 17beta-estradiol (E2) combined with norethisterone acetate (NETA) on markers of inflammation in healthy post-menopausal women. METHODS: Ninety healthy post-menopausal women (age 56.6 +/- 4.7 years) participated in this 1-year trial. After computerized block randomization, they daily received, in a double-blind fashion, either intranasal E2/NET [175 microg/275 microg (n = 47)] or oral E2/NETA [1 mg/0.5 mg (n = 43)]. Concentrations of high sensitivity CRP and adhesion molecules were measured at baseline and after 12, 24 and 52 weeks of treatment. RESULTS: CRP levels were increased (P = 0.001) in the oral but not in the intranasal group. The increase in the oral group was highest at week 12 (64.9%) and was larger (P < 0.01) compared with the non-significant increase (8.6%) found in the intranasal group. Both groups showed decreases (P < 0.001) in soluble vascular cell adhesion molecule (sVCAM), soluble intracellular adhesion molecule (sICAM) and sE-selectin. The decreases were larger (P < 0.01) in the oral than in the intranasal group. CONCLUSION: Intranasal E2/NET therapy did not significantly increase CRP levels, in contrast to the increase observed in the oral E2/NETA treatment group. Both intranasal and oral therapy lowered plasma concentrations of adhesion molecules, however, more so in the oral group.


Asunto(s)
Proteína C-Reactiva/biosíntesis , Estradiol/administración & dosificación , Regulación de la Expresión Génica , Administración Intranasal , Administración Oral , Adulto , Anciano , Terapia de Reemplazo de Estrógeno/métodos , Femenino , Humanos , Molécula 1 de Adhesión Intercelular/sangre , Persona de Mediana Edad , Posmenopausia , Ensayos Clínicos Controlados Aleatorios como Asunto , Molécula 1 de Adhesión Celular Vascular/sangre
8.
J Intern Med ; 259(2): 199-208, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16420549

RESUMEN

OBJECTIVE: To compare the effects of oral and transdermal hormone therapy (HT) on asymmetric dimethylarginine (ADMA), an endogenous inhibitor of nitric oxide synthase, in postmenopausal women. DESIGN: In a multicentre, placebo-controlled, double-blind study, 152 hysterectomized healthy women were randomized to receive daily transdermal 17beta-oestradiol (tE2, n = 33), or oral micronized 17beta-oestradiol either unopposed (oE2, n = 37), or continuous combined with gestodene (oE2 + G, n = 33), or placebo (n = 49) for 13, 28-day treatment cycles. Plasma concentrations of ADMA, arginine and symmetric dimethylarginine (SDMA) were measured at baseline and in treatment cycles 4 and 13 with a high-performance liquid chromatography method. RESULTS: After 13 cycles all active treatment groups showed a significant reduction in ADMA compared with placebo: tE2, -4.0% (95% CI: -7.5 to -0.6%); oE2, -7.7% (95% CI: -10.9 to -4.4%) and oE2 + G, -7.5% (95% CI: -10.8 to -4.3%). ancova showed a significantly larger reduction in the oral groups compared with the transdermal group (tE2 vs. oE2 and tE2 vs. oE2 + G, both P < 0.01). Oral, but not transdermal treatment, significantly reduced arginine compared with placebo. All active treatments reduced SDMA; however, this was only statistically significant in the oE2 group. CONCLUSION: Reduction of ADMA was more pronounced after oral than after tE2 administration. Adding gestodene to oral 17beta-oestradiol did not alter the reduction of ADMA. The clinical implications of these findings remain uncertain; however, the decrease of ADMA by 17beta-oestradiol could be a key phenomenon in the modulation of nitric oxide synthesis by postmenopausal HT.


Asunto(s)
Arginina/análogos & derivados , Terapia de Reemplazo de Estrógeno , Estrógenos/administración & dosificación , Posmenopausia/sangre , Administración Cutánea , Administración Oral , Anciano , Análisis de Varianza , Arginina/sangre , Cromatografía Líquida de Alta Presión/métodos , Método Doble Ciego , Femenino , Humanos , Histerectomía , Persona de Mediana Edad , Norpregnenos/administración & dosificación
9.
Maturitas ; 51(1): 4-7, 2005 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-15883102

RESUMEN

The fourth Amsterdam Menopause Symposium (2-4 October 2004) was dedicated to practical recommendations to guide clinicians after the confusion, concerns, and controversies generated by study results over the previous several years. Those recommendations are summarized in this deliberately concise and user-friendly document, always recognizing that each clinician must help women with their decision-making according to individual needs, desires, and understanding of benefits and risks.


Asunto(s)
Terapia de Reemplazo de Estrógeno , Guías de Práctica Clínica como Asunto , Enfermedad de Alzheimer/prevención & control , Neoplasias de la Mama/inducido químicamente , Enfermedades Cardiovasculares/inducido químicamente , Terapia de Reemplazo de Estrógeno/efectos adversos , Femenino , Humanos , Osteoporosis Posmenopáusica/prevención & control , Posmenopausia , Progestinas/administración & dosificación , Progestinas/efectos adversos
10.
Maturitas ; 51(1): 21-8, 2005 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-15883105

RESUMEN

An international multidisciplinary panel of experts in the management of the menopause met at the 4th Amsterdam Menopause Symposium in October 2004 to determine the specific place of tibolone, a synthetic steroid with a unique clinical profile, within the wide range of currently available postmenopausal therapy options. The consensus was that tibolone is a valuable treatment option for women with climacteric complaints. As well as relieving vasomotor symptoms, tibolone has positive effects on sexual well-being and mood, and improves vaginal atrophy and urogenital symptoms. Prevention of bone loss with tibolone is comparable to that seen with estrogen therapy (ET) and estrogen/progestogen therapy (EPT). As tibolone rarely causes endometrial proliferation, no additional progestogen is required. It also has good tolerability, being associated with a low incidence of vaginal bleeding and of breast pain. Tibolone does not increase mammographic density. Absolute numbers of women at increased risk for breast cancer are estimated to be low or absent with both tibolone and ET, and the risk with tibolone should be significantly lower than that with EPT. Tibolone might therefore be preferable to EPT in certain women who have not been hysterectomised. Based on the evidence available, the panel proposed a number of subgroups of postmenopausal women with vasomotor symptoms in whom tibolone might have added value; these included women with sexual dysfunction, mood disorders, fibroids and urogenital complaints, as well as those with breast tenderness or high mammographic breast density with EPT use.


Asunto(s)
Moduladores de los Receptores de Estrógeno/uso terapéutico , Terapia de Reemplazo de Estrógeno , Menopausia/efectos de los fármacos , Norpregnenos/uso terapéutico , Moduladores de los Receptores de Estrógeno/efectos adversos , Femenino , Humanos , Menopausia/psicología , Norpregnenos/efectos adversos , Ensayos Clínicos Controlados Aleatorios como Asunto , Sexualidad/efectos de los fármacos , Sexualidad/psicología
11.
J Clin Endocrinol Metab ; 90(4): 2218-24, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15671107

RESUMEN

Estrogens, both endogenous and exogenous, lower the fasting levels of the independent risk factor for cardiovascular disease homocysteine. The mechanism behind this observation remains unclear. In a randomized, placebo-controlled, double-blind study, 25 postmenopausal women with a screening homocysteine concentration above 10 micromol/liter were included. We investigated the influence on homocysteine levels of a 3-month treatment with a daily oral dose of 4 mg 17beta-estradiol (ET) or 4 mg ET combined with 10 mg dydrogesterone (EPT); the comparison group received placebo treatment. We performed primed continuous infusions of L-[2H3-methyl-13C]methionine to assess steady-state flux rates of transmethylation, remethylation, and transsulfuration. Homocysteine concentration relationships with S-adenosylmethionine, S-adenosylhomocysteine, creatinine, albumin, vitamins B6 and B12, and folate status were determined as well. The mean change from baseline in homocysteine concentration by both treatments compared with placebo (ET, -13%; EPT, -10%) was accompanied by a decrease in the concentration of vitamin B6 (ET, -25%; EPT, -38%) and albumin (ET, -7%; EPT, -11%). No significant changes in flux rates were observed. In a .multiltivariate analysis, changes in homocysteine concentration were related to changes in albumin concentration. No relation to other variables was observed. We conclude that the ET- and EPT-induced homocysteine changes in this study were not accompanied by a significant change in methionine-homocysteine flux rates and hypothesize that an estrogen-induced lowering of homocysteine levels is primarily part of a change in albumin metabolism.


Asunto(s)
Estradiol/farmacología , Terapia de Reemplazo de Estrógeno , Homocisteína/sangre , Posmenopausia/sangre , Albúmina Sérica/análisis , Vitamina B 6/sangre , Anciano , Método Doble Ciego , Femenino , Homocisteína/metabolismo , Humanos , Metilación , Persona de Mediana Edad
12.
Eur J Obstet Gynecol Reprod Biol ; 117(1): 55-9, 2004 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-15474245

RESUMEN

OBJECTIVE: To investigate the mechanism by which exogenous oestrogen influences the homocysteine metabolism in postmenopausal women. STUDY DESIGN: A randomized placebo controlled trial in which a methionine-loading test was performed, in 25 healthy postmenopausal women, before and after a 12-week oral treatment with placebo or daily 4 mg 17beta-estradiol with (HRT) or without (ERT) 10 mg dydrogesterone. Fasting and post-load homocysteine as well as Vitamins B(6), B(12) and folate were determined. RESULTS: In both treatment groups a significant 12% decrease in fasting homocysteine was observed. This decrease was accompanied by a post-load homocysteine increase of more than 20%. Vitamin B(6) values were decreased by more than 25%. CONCLUSION: The hormone therapy induced lowering of fasting homocysteine and Vitamin B(6) levels and an increase in post-load homocysteine, supporting the hypothesis that homocysteine-methionine metabolism is modulated by hormone therapy in postmenopausal women.


Asunto(s)
Didrogesterona/administración & dosificación , Estradiol/administración & dosificación , Terapia de Reemplazo de Estrógeno , Homocisteína/sangre , Metionina/administración & dosificación , Posmenopausia/sangre , Análisis de Varianza , Análisis Químico de la Sangre , Método Doble Ciego , Femenino , Ácido Fólico/sangre , Humanos , Persona de Mediana Edad , Piridoxina/sangre , Resultado del Tratamiento , Vitamina B 12/sangre
13.
Maturitas ; 49(1): 34-43, 2004 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-15351094

RESUMEN

Cancer is a genetic disease. Breast cancer tumorigenesis can be described as a multi-step process in which each step is thought to correlate with one or more distinct mutations in major regulatory genes. The question addressed is how far a multi-step progression model for sporadic breast cancer would differ from that for hereditary breast cancer. Hereditary breast cancer is characterized by an inherited susceptibility to breast cancer on basis of an identified germline mutation in one allele of a high penetrance susceptibility gene (such as BRCA1, BRCA2, CHEK 2, TP53 or PTEN). Inactivation of the second allele of these tumour suppressor genes would be an early event in this oncogenic pathway (Knudson's "two-hit" model). Sporadic breast cancers result from a serial stepwise accumulation of acquired and uncorrected mutations in somatic genes, without any germline mutation playing a role. Mutational activation of oncogenes, often coupled with non-mutational inactivation of tumour suppressor genes, is probably an early event in sporadic tumours, followed by more, independent mutations in at least four or five other genes, the chronological order of which is likely less important. Oncogenes that have been reported to play an early role in sporadic breast cancer are MYC, CCND1 (Cyclin D1) and ERBB2 (HER2/neu). In sporadic breast cancer, mutational inactivation of BRCA1/2 is rare, as inactivation requires both gene copies to be mutated or totally deleted. However, non-mutational functional suppression could result from various mechanisms, such as hypermethylation of the BRCA1 promoter or binding of BRCA2 by EMSY. In sporadic breast tumorigenesis, at least three different pathway-specific mechanisms of tumour progression are recognizable, with breast carcinogenesis being different in ductal versus lobular carcinoma, and in well differentiated versus poorly differentiated ductal cancers. Thus, different breast cancer pathways emerge early in the process of carcinogenesis, ultimately leading to clinically different tumour types. As mutations acquired early during tumorigenesis will be present in all later stages, large-scale gene expression profiling using DNA microarray analysis techniques can help to classify breast cancers into clinically relevant subtypes.


Asunto(s)
Neoplasias de la Mama/genética , Predisposición Genética a la Enfermedad , Mutación , Transformación Celular Neoplásica , Progresión de la Enfermedad , Femenino , Humanos , Modelos Genéticos
14.
Gynecol Endocrinol ; 18(3): 159-64, 2004 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15255285

RESUMEN

All postmenopausal hormone replacement therapies (HTs) aim to provide a steady mid-follicular serum concentration of estrogen, with the exception of pulsed estrogen therapy, which concentrates hormone exposure in the few hours following administration. This alteration in the kinetics of estradiol exposure does not change the beneficial effect of HT on climacteric symptoms or bone loss, but does reduce the stimulation of the breast and uterus leading to less mastalgia and bleeding. The following hypothesis provides a plausible pharmacological explanation as to how estradiol kinetics can selectively modify tissue response. Pulsed estradiol exposure influences the relative abundance of estrogen receptors (ERs) alpha and beta, via a tissue-dependent non-genomic signaling pathway, resulting in selective upregulation and activation of ERbeta in breast and endometrium, but not in bone. In addition, pulsed estrogen exposure also increases local concentration of 2-methoxyestradiol, a specific estradiol metabolite with proven anti-tumor properties.


Asunto(s)
Estradiol/análogos & derivados , Estradiol/administración & dosificación , Terapia de Reemplazo de Estrógeno/métodos , Modelos Biológicos , Posmenopausia , 2-Metoxiestradiol , Administración Intranasal , Animales , Mama/química , Mama/efectos de los fármacos , Endometrio/química , Endometrio/efectos de los fármacos , Estradiol/análisis , Estradiol/farmacocinética , Receptor alfa de Estrógeno , Receptor beta de Estrógeno , Femenino , Humanos , Cinética , Periodicidad , Receptores de Estrógenos/análisis , Transducción de Señal
16.
Eur J Obstet Gynecol Reprod Biol ; 113(1): 3-5, 2004 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-15036701

RESUMEN

The Million Women Study (MWS), published in the summer of 2003, has suggested unexpected high risks for invasive breast cancer in women using postmenopausal hormone therapy (PHT). Recent reports from randomised controlled trials (RCTs) have demonstrated that long-term combined PHT is associated with a small risk increase for invasive breast cancer, but not for death due to breast cancer. The observational design of the MWS has made this study subject to several biases, that can easily explain the discrepancy with the observations done in RCTs and several other large observational studies. It is concluded that the hormone fear that was caused by the MWS, and augmented by some professionals and the media, was unjustifiable.


Asunto(s)
Neoplasias de la Mama/inducido químicamente , Terapia de Reemplazo de Estrógeno/efectos adversos , Femenino , Humanos , Posmenopausia , Ensayos Clínicos Controlados Aleatorios como Asunto , Proyectos de Investigación
17.
Gynecol Endocrinol ; 17(4): 339-54, 2003 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-14503980

RESUMEN

Estrogens influence the independent cardiovascular risk factor homocysteine as well as vasodilatation. Homocysteine alone also influences vasodilatation, indicating a relational triangle that seems important in interpreting the isolated effects of estrogens on homocysteine metabolism and vasoreactivity. This paper gives an overview of the current understanding regarding vasoreactivity, homocysteine metabolism and the role of estrogens. This is placed against the background of the clinical trials on the effect of postmenopausal hormone replacement therapy on homocysteine levels and addresses the importance of the interaction between homocysteine, estrogens and vasoreactivity.


Asunto(s)
Estrógenos/fisiología , Homocisteína/fisiología , Posmenopausia/fisiología , Vasodilatación/fisiología , Enfermedades Cardiovasculares/fisiopatología , Enfermedades Cardiovasculares/prevención & control , Ensayos Clínicos como Asunto , Terapia de Reemplazo de Estrógeno , Femenino , Homocisteína/metabolismo , Humanos
18.
Histopathology ; 43(1): 26-32, 2003 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12823709

RESUMEN

AIMS: To investigate the occurrence of preinvasive neoplastic lesions in ovarian surface epithelium and ovarian inclusion cyst epithelium of women with a hereditary predisposition to the development of female adnexal (ovarian and fallopian tube) carcinoma and to assess the expression of differentiation and proliferation related proteins within putative sites of origin of serous ovarian carcinoma, the ovarian surface epithelium and ovarian inclusion cyst epithelium. METHODS: Twenty-one ovaries, prophylactically removed from 11 women predisposed to the development of female adnexal cancer (cases) were compared with 22 ovaries from 11 women without such predisposition (controls). Archival histological specimens were screened for hyperplastic and dysplastic epithelial lesions. In both the ovarian surface and inclusion cyst epithelia, the percentage of cells was determined that stained positively for Ki67, p21, p27, p53, cyclin A, cyclin D1, bcl-2 and the presence of HER-2/neu, oestrogen (ER-alpha) and progesterone receptors (PR). RESULTS: No preinvasive neoplastic lesions were detected. However, hyperplastic areas were found in three cases and in four controls (NS). ER-alpha (P = 0.013), PR (P < 0.001), bcl-2 (P = 0.008), p21 (P = 0.046) and p27 (P = 0.008) were expressed in a significantly higher percentage of cells in inclusion cyst epithelium than in ovarian surface epithelium (both groups). The latter showed higher bcl-2 expression in cases (P = 0.05) compared with controls. The inclusion cyst epithelium of cases showed higher expression of bcl-2 (P = 0.006) and PR (P = 0.039) compared with controls. Proliferation was low in both cases and controls as reflected by low Ki67 expression. Over-expression of p53, cyclin D1 and HER-2/neu was not detected. CONCLUSIONS: Premalignant changes are not a common feature of ovaries removed prophylactically from women predisposed to the development of female adnexal carcinoma. Increased expression of p21, p27, and ER-alpha is seen in inclusion cyst compared with ovarian surface epithelium of women with and without an inherited risk of adnexal carcinoma. This is most probably caused by the different intraovarian hormonal milieu of inclusion cyst epithelium. However, the increased expression of bcl-2 and PR in the inclusion cyst epithelium of patients with a hereditary predisposition may reflect early disruption of hormonal balance and growth control.


Asunto(s)
Enfermedades de los Anexos/metabolismo , Transformación Celular Neoplásica/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias Ováricas/metabolismo , Ovario/metabolismo , Lesiones Precancerosas/metabolismo , Enfermedades de los Anexos/genética , Enfermedades de los Anexos/patología , Adulto , Anciano , Biomarcadores de Tumor/metabolismo , Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/patología , Epitelio/metabolismo , Epitelio/patología , Trompas Uterinas/patología , Femenino , Predisposición Genética a la Enfermedad , Humanos , Técnicas para Inmunoenzimas , Persona de Mediana Edad , Neoplasias Ováricas/genética , Neoplasias Ováricas/patología , Ovariectomía , Ovario/patología , Lesiones Precancerosas/genética , Lesiones Precancerosas/patología
19.
Best Pract Res Clin Endocrinol Metab ; 17(1): 123-37, 2003 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12763516

RESUMEN

From the introduction of post-menopausal hormone replacement therapy (HRT) there has been great concern that HRT could possibly increase the risk of breast cancer. Prolonged exposure to endogenous oestrogens undeniably increases the risk of breast cancer. Questions that are important and until now only partly answered, are the following. Are oestrogens tumour promoters, as they induce mitosis, lead to proliferation and, therefore, accelerated growth of clinically occult pre-existing tumours? In addition to this, are they genotoxic mutagenic carcinogens, or could they initiate tumours by way of accumulation of incessant DNA-replication damage mechanism? Opinions vary as to the effect of the addition of a progestogen. There is a multitude of different progestogens which could bind with differing affinity to progesterone receptor PR-A or PR-B, and which have different physiological functions via differential gene regulation. The action of a progestogen on the oestrogen-induced cellular mitotic activity could be synergistic or antagonistic (by different pathways: oestrogen receptor downregulation, activating of metabolic pathways within the breast or stimulation of apoptosis)? Over 60 observational studies and two randomized trials provide evidence that the small but significant increase in risk appears with long-term current post-menopausal hormone use. The addition of a progestogen does not decrease the risk as seen with oestrogens alone and might increase the risk further. It is not clear whether there is a difference in risk with sequentially combined versus continuously combined HRT. Many questions nevertheless still remain. Is the risk increase limited to lean women only? What about risk-modifying factors such as alcohol use and a positive family history for breast cancer? Are tumours detected under HRT less aggressive, is there a better prognosis and is the mortality not increased while morbidity is? And is HRT contraindicated for women with a positive family history for breast cancer or in those women who have been treated for breast cancer? And finally, are there alternative options for these women?


Asunto(s)
Neoplasias de la Mama/inducido químicamente , Terapia de Reemplazo de Estrógeno/efectos adversos , Estrógenos/efectos adversos , Progestinas/efectos adversos , Neoplasias de la Mama/epidemiología , Femenino , Humanos , Posmenopausia , Factores de Riesgo
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