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JAMA | 2013

Menopausal hormone therapy and health outcomes during the intervention and extended poststopping phases of the Women's Health Initiative randomized trials.

JoAnn E. Manson; Rowan T. Chlebowski; Marcia L. Stefanick; Aaron K. Aragaki; Jacques E. Rossouw; Ross L. Prentice; Garnet L. Anderson; Barbara V. Howard; Cynthia A. Thomson; Andrea Z. LaCroix; Jean Wactawski-Wende; Rebecca D. Jackson; Marian C. Limacher; Karen L. Margolis; Sylvia Wassertheil-Smoller; Shirley A A Beresford; Jane A. Cauley; Charles B. Eaton; Margery Gass; Judith Hsia; Karen C. Johnson; Charles Kooperberg; Lewis H. Kuller; Cora E. Lewis; Simin Liu; Lisa W. Martin; Judith K. Ockene; Mary Jo O’Sullivan; Lynda H. Powell; Michael S. Simon

IMPORTANCE Menopausal hormone therapy continues in clinical use but questions remain regarding its risks and benefits for chronic disease prevention. OBJECTIVE To report a comprehensive, integrated overview of findings from the 2 Womens Health Initiative (WHI) hormone therapy trials with extended postintervention follow-up. DESIGN, SETTING, AND PARTICIPANTS A total of 27,347 postmenopausal women aged 50 to 79 years were enrolled at 40 US centers. INTERVENTIONS Women with an intact uterus received conjugated equine estrogens (CEE; 0.625 mg/d) plus medroxyprogesterone acetate (MPA; 2.5 mg/d) (n = 8506) or placebo (n = 8102). Women with prior hysterectomy received CEE alone (0.625 mg/d) (n = 5310) or placebo (n = 5429). The intervention lasted a median of 5.6 years in CEE plus MPA trial and 7.2 years in CEE alone trial with 13 years of cumulative follow-up until September 30, 2010. MAIN OUTCOMES AND MEASURES Primary efficacy and safety outcomes were coronary heart disease (CHD) and invasive breast cancer, respectively. A global index also included stroke, pulmonary embolism, colorectal cancer, endometrial cancer, hip fracture, and death. RESULTS During the CEE plus MPA intervention phase, the numbers of CHD cases were 196 for CEE plus MPA vs 159 for placebo (hazard ratio [HR], 1.18; 95% CI, 0.95-1.45) and 206 vs 155, respectively, for invasive breast cancer (HR, 1.24; 95% CI, 1.01-1.53). Other risks included increased stroke, pulmonary embolism, dementia (in women aged ≥65 years), gallbladder disease, and urinary incontinence; benefits included decreased hip fractures, diabetes, and vasomotor symptoms. Most risks and benefits dissipated postintervention, although some elevation in breast cancer risk persisted during cumulative follow-up (434 cases for CEE plus MPA vs 323 for placebo; HR, 1.28 [95% CI, 1.11-1.48]). The risks and benefits were more balanced during the CEE alone intervention with 204 CHD cases for CEE alone vs 222 cases for placebo (HR, 0.94; 95% CI, 0.78-1.14) and 104 vs 135, respectively, for invasive breast cancer (HR, 0.79; 95% CI, 0.61-1.02); cumulatively, there were 168 vs 216, respectively, cases of breast cancer diagnosed (HR, 0.79; 95% CI, 0.65-0.97). Results for other outcomes were similar to CEE plus MPA. Neither regimen affected all-cause mortality. For CEE alone, younger women (aged 50-59 years) had more favorable results for all-cause mortality, myocardial infarction, and the global index (nominal P < .05 for trend by age). Absolute risks of adverse events (measured by the global index) per 10,000 women annually taking CEE plus MPA ranged from 12 excess cases for ages of 50-59 years to 38 for ages of 70-79 years; for women taking CEE alone, from 19 fewer cases for ages of 50-59 years to 51 excess cases for ages of 70-79 years. Quality-of-life outcomes had mixed results in both trials. CONCLUSIONS AND RELEVANCE Menopausal hormone therapy has a complex pattern of risks and benefits. Findings from the intervention and extended postintervention follow-up of the 2 WHI hormone therapy trials do not support use of this therapy for chronic disease prevention, although it is appropriate for symptom management in some women. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00000611.


JAMA | 2010

Estrogen plus progestin and breast cancer incidence and mortality in postmenopausal women.

Rowan T. Chlebowski; Garnet L. Anderson; Margery Gass; Dorothy S. Lane; Aaron K. Aragaki; Lewis H. Kuller; JoAnn E. Manson; Marcia L. Stefanick; Judith K. Ockene; Gloria E. Sarto; Karen C. Johnson; Jean Wactawski-Wende; Peter M. Ravdin; Robert S. Schenken; Susan L. Hendrix; Aleksandar Rajkovic; Thomas E. Rohan; Shagufta Yasmeen; Ross L. Prentice

CONTEXT In the Womens Health Initiative randomized, placebo-controlled trial of estrogen plus progestin, after a mean intervention time of 5.6 (SD, 1.3) years (range, 3.7-8.6 years) and a mean follow-up of 7.9 (SD, 1.4) years, breast cancer incidence was increased among women who received combined hormone therapy. Breast cancer mortality among participants in the trial has not been previously reported. OBJECTIVE To determine the effects of therapy with estrogen plus progestin on cumulative breast cancer incidence and mortality after a total mean follow-up of 11.0 (SD, 2.7) years, through August 14, 2009. DESIGN, SETTING, AND PARTICIPANTS A total of 16,608 postmenopausal women aged 50 to 79 years with no prior hysterectomy from 40 US clinical centers were randomly assigned to receive combined conjugated equine estrogens, 0.625 mg/d, plus medroxyprogesterone acetate, 2.5 mg/d, or placebo pill. After the original trial completion date (March 31, 2005), reconsent was required for continued follow-up for breast cancer incidence and was obtained from 12,788 (83%) of the surviving participants. MAIN OUTCOME MEASURES Invasive breast cancer incidence and breast cancer mortality. RESULTS In intention-to-treat analyses including all randomized participants and censoring those not consenting to additional follow-up on March 31, 2005, estrogen plus progestin was associated with more invasive breast cancers compared with placebo (385 cases [0.42% per year] vs 293 cases [0.34% per year]; hazard ratio [HR], 1.25; 95% confidence interval [CI], 1.07-1.46; P = .004). Breast cancers in the estrogen-plus-progestin group were similar in histology and grade to breast cancers in the placebo group but were more likely to be node-positive (81 [23.7%] vs 43 [16.2%], respectively; HR, 1.78; 95% CI, 1.23-2.58; P = .03). There were more deaths directly attributed to breast cancer (25 deaths [0.03% per year] vs 12 deaths [0.01% per year]; HR, 1.96; 95% CI, 1.00-4.04; P = .049) as well as more deaths from all causes occurring after a breast cancer diagnosis (51 deaths [0.05% per year] vs 31 deaths [0.03% per year]; HR, 1.57; 95% CI, 1.01-2.48; P = .045) among women who received estrogen plus progestin compared with women in the placebo group. CONCLUSIONS Estrogen plus progestin was associated with greater breast cancer incidence, and the cancers are more commonly node-positive. Breast cancer mortality also appears to be increased with combined use of estrogen plus progestin. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00000611.


The New England Journal of Medicine | 2009

Breast Cancer after Use of Estrogen plus Progestin in Postmenopausal Women

Rowan T. Chlebowski; Lewis H. Kuller; Ross L. Prentice; Marcia L. Stefanick; JoAnn E. Manson; Margery Gass; Aaron K. Aragaki; Judith K. Ockene; Dorothy S. Lane; Gloria E. Sarto; Aleksandar Rajkovic; Robert S. Schenken; Susan L. Hendrix; Peter M. Ravdin; Thomas E. Rohan; Shagufta Yasmeen; Garnet L. Anderson

BACKGROUND Following the release of the 2002 report of the Womens Health Initiative (WHI) trial of estrogen plus progestin, the use of menopausal hormone therapy in the United States decreased substantially. Subsequently, the incidence of breast cancer also dropped, suggesting a cause-and-effect relation between hormone treatment and breast cancer. However, the cause of this decrease remains controversial. METHODS We analyzed the results of the WHI randomized clinical trial--in which one study group received 0.625 mg of conjugated equine estrogens plus 2.5 mg of medroxyprogesterone acetate daily and another group received placebo--and examined temporal trends in breast-cancer diagnoses in the WHI observational-study cohort. Risk factors for breast cancer, frequency of mammography, and time-specific incidence of breast cancer were assessed in relation to combined hormone use. RESULTS In the clinical trial, there were fewer breast-cancer diagnoses in the group receiving estrogen plus progestin than in the placebo group in the initial 2 years of the study, but the number of diagnoses increased over the course of the 5.6-year intervention period. The elevated risk decreased rapidly after both groups stopped taking the study pills, despite a similar frequency of mammography. In the observational study, the incidence of breast cancer was initially about two times as high in the group receiving menopausal hormones as in the placebo group, but this difference in incidence decreased rapidly in about 2 years, coinciding with year-to-year reductions in combined hormone use. During this period, differences in the frequency of mammography between the two groups were unchanged. CONCLUSIONS The increased risk of breast cancer associated with the use of estrogen plus progestin declined markedly soon after discontinuation of combined hormone therapy and was unrelated to changes in frequency of mammography.


JAMA | 2011

Health Outcomes After Stopping Conjugated Equine Estrogens Among Postmenopausal Women With Prior Hysterectomy: A Randomized Controlled Trial

Andrea Z. LaCroix; Rowan T. Chlebowski; JoAnn E. Manson; Aaron K. Aragaki; Karen C. Johnson; Lisa Martin; Karen L. Margolis; Marcia L. Stefanick; Robert G. Brzyski; J. David Curb; Barbara V. Howard; Cora E. Lewis

CONTEXT The Womens Health Initiative Estrogen-Alone Trial was stopped early after a mean of 7.1 years of follow-up because of an increased risk of stroke and little likelihood of altering the balance of risk to benefit by the planned trial termination date. Postintervention health outcomes have not been reported. OBJECTIVE To examine health outcomes associated with randomization to treatment with conjugated equine estrogens (CEE) among women with prior hysterectomy after a mean of 10.7 years of follow-up through August 2009. DESIGN, SETTING, AND PARTICIPANTS The intervention phase was a double-blind, placebo-controlled, randomized clinical trial of 0.625 mg/d of CEE compared with placebo in 10,739 US postmenopausal women aged 50 to 79 years with prior hysterectomy. Follow-up continued after the planned trial completion date among 7645 surviving participants (78%) who provided written consent. MAIN OUTCOME MEASURES The primary outcomes were coronary heart disease (CHD) and invasive breast cancer. A global index of risks and benefits included these primary outcomes plus stroke, pulmonary embolism, colorectal cancer, hip fracture, and death. RESULTS The postintervention risk (annualized rate) for CHD among women assigned to CEE was 0.64% compared with 0.67% in the placebo group (hazard ratio [HR], 0.97; 95% confidence interval [CI], 0.75-1.25), 0.26% vs 0.34%, respectively, for breast cancer (HR, 0.75; 95% CI, 0.51-1.09), and 1.47% vs 1.48%, respectively, for total mortality (HR, 1.00; 95% CI, 0.84-1.18). The risk of stroke was no longer elevated during the postintervention follow-up period and was 0.36% among women receiving CEE compared with 0.41% in the placebo group (HR, 0.89; 95% CI, 0.64-1.24), the risk of deep vein thrombosis was lower at 0.17% vs 0.27%, respectively (HR, 0.63; 95% CI, 0.41-0.98), and the risk of hip fracture did not differ significantly and was 0.36% vs 0.28%, respectively (HR, 1.27; 95% CI, 0.88-1.82). Over the entire follow-up, lower breast cancer incidence in the CEE group persisted and was 0.27% compared with 0.35% in the placebo group (HR, 0.77; 95% CI, 0.62-0.95). Health outcomes were more favorable for younger compared with older women for CHD (P = .05 for interaction), total myocardial infarction (P = .007 for interaction), colorectal cancer (P = .04 for interaction), total mortality (P = .04 for interaction), and global index of chronic diseases (P = .009 for interaction). CONCLUSIONS Among postmenopausal women with prior hysterectomy followed up for 10.7 years, CEE use for a median of 5.9 years was not associated with an increased or decreased risk of CHD, deep vein thrombosis, stroke, hip fracture, colorectal cancer, or total mortality. A decreased risk of breast cancer persisted. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00000611.


JAMA | 2008

Health risks and benefits 3 years after stopping randomized treatment with estrogen and progestin.

Gerardo Heiss; Robert B. Wallace; Garnet L. Anderson; Aaron K. Aragaki; Shirley A A Beresford; Robert G. Brzyski; Rowan T. Chlebowski; Margery Gass; Andrea Z. LaCroix; JoAnn E. Manson; Ross L. Prentice; Jacques E. Rossouw; Marcia L. Stefanick

CONTEXT The Womens Health Initiative (WHI) trial of estrogen plus progestin vs placebo was stopped early, after a mean 5.6 years of follow-up, because the overall health risks of hormone therapy exceeded its benefits. OBJECTIVE To report health outcomes at 3 years (mean 2.4 years of follow-up) after the intervention was stopped. DESIGN, SETTING, AND PARTICIPANTS The intervention phase was a double-blind, placebo-controlled, randomized trial of conjugated equine estrogens (CEE) 0.625 mg daily plus medroxyprogesterone acetate (MPA) 2.5 mg daily, in 16,608 women aged 50 through 79 years, recruited by 40 centers from 1993 to 1998. The postintervention phase commenced July 8, 2002, and included 15 730 women. MAIN OUTCOME MEASURES Semi-annual monitoring and outcomes ascertainment continued per trial protocol. The primary end points were coronary heart disease and invasive breast cancer. A global index summarizing the balance of risks and benefits included the 2 primary end points plus stroke, pulmonary embolism, endometrial cancer, colorectal cancer, hip fracture, and death due to other causes. RESULTS The risk of cardiovascular events after the intervention was comparable by initial randomized assignments, 1.97% (annualized rate) in the CEE plus MPA (343 events) and 1.91% in the placebo group (323 events). A greater risk of malignancies occurred in the CEE plus MPA than in the placebo group (1.56% [n = 281] vs 1.26% [n = 218]; hazard ratio [HR], 1.24; 95% confidence interval [CI], 1.04-1.48). More breast cancers were diagnosed in women who had been randomly assigned to receive CEE plus MPA vs placebo (0.42% [n = 79] vs 0.33% [n = 60]; HR, 1.27; 95% CI, 0.91-1.78) with a modest trend toward a lower HR during the follow-up after the intervention. All-cause mortality was somewhat higher in the CEE plus MPA than in the placebo group (1.20% [n = 233] vs 1.06% [n = 196]; HR, 1.15; 95% CI, 0.95-1.39). The global index of risks and benefits was unchanged from randomization through March 31, 2005 (HR, 1.12; 95% CI, 1.03-1.21), indicating that the risks of CEE plus MPA exceed the benefits for chronic disease prevention. CONCLUSIONS The increased cardiovascular risks in the women assigned to CEE plus MPA during the intervention period were not observed after the intervention. A greater risk of fatal and nonfatal malignancies occurred after the intervention in the CEE plus MPA group and the global risk index was 12% higher in women randomly assigned to receive CEE plus MPA compared with placebo. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00000611.


Circulation | 2006

Effects of Conjugated Equine Estrogen on Stroke in the Women’s Health Initiative

Susan L. Hendrix; Sylvia Wassertheil-Smoller; Karen C. Johnson; Barbara V. Howard; Charles Kooperberg; Jacques E. Rossouw; Maurizio Trevisan; Aaron K. Aragaki; Alison E. Baird; Paul F. Bray; Julie E. Buring; Michael H. Criqui; David M. Herrington; John K. Lynch; Stephen R. Rapp; James C. Torner

Background— The Women’s Health Initiative (WHI) Estrogen Alone trial assessed the balance of benefits and risks of hormone use in healthy postmenopausal women. The trial was stopped prematurely because there was no benefit for coronary heart disease and an increased risk of stroke. This report provides a thorough analysis of the stroke finding using the final results from the completed trial database. Methods and Results— The WHI Estrogen Alone hormone trial is a multicenter, double-blind, placebo-controlled, randomized clinical trial in 10 739 women aged 50 to 79 years who were given daily conjugated equine estrogen (CEE; 0.625 mg; n=5310) or placebo (n=5429). During an average follow-up of 7.1 years, there were 168 strokes in the CEE group and 127 in the placebo group; 80.3% of strokes were ischemic. For all stroke the intention-to-treat hazard ratio [HR] (95% CI) for CEE versus placebo was 1.37 (1.09 to 1.73). The HR (95% CI) was 1.55 (1.19 to 2.01) for ischemic stroke and 0.64 (0.35, 1.18) for hemorrhagic stroke. The HRs indicate excess risk of ischemic stroke was apparent in all categories of baseline stroke risk, including younger and more recently menopausal women and in women with prior or current use of statins or aspirin. Conclusions— CEE increases the risk of ischemic stroke in generally healthy postmenopausal women. The excess risk appeared to be present in all subgroups of women examined, including younger and more recently menopausal women. There was no convincing evidence to suggest that CEE had an effect on the risk of hemorrhagic stroke.


Lancet Oncology | 2012

Conjugated equine oestrogen and breast cancer incidence and mortality in postmenopausal women with hysterectomy: Extended follow-up of the Women's Health Initiative randomised placebo-controlled trial

Garnet L. Anderson; Rowan T. Chlebowski; Aaron K. Aragaki; Lewis H. Kuller; JoAnn E. Manson; Margery Gass; Elizabeth C. Bluhm; Stephanie Connelly; F. Allan Hubbell; Dorothy S. Lane; Lisa W. Martin; Judith K. Ockene; Thomas E. Rohan; Robert S. Schenken; Jean Wactawski-Wende

BACKGROUND By contrast with many observational studies, women in the Womens Health Initiative (WHI) trial who were randomly allocated to receive oestrogen alone had a lower incidence of invasive breast cancer than did those who received placebo. We aimed to assess the influence of oestrogen use on longer term breast cancer incidence and mortality in extended follow-up of this cohort. METHODS Between 1993 and 1998, the WHI enrolled 10,739 postmenopausal women from 40 US clinical centres into a randomised, double-masked, placebo-controlled trial. Women aged 50-79 years who had undergone hysterectomy and had expected 3-year survival and mammography clearance were randomly allocated by a computerised, permuted block algorithm, stratified by age group and centre, to receive oral conjugated equine oestrogen (0·625 mg per day; n=5310) or matched placebo (n=5429). The trial intervention was terminated early on Feb 29, 2004, because of an adverse effect on stroke. Follow-up continued until planned termination (March 31, 2005). Consent was sought for extended surveillance from the 9786 living participants in active follow-up, of whom 7645 agreed. Using data from this extended follow-up (to Aug 14, 2009), we assessed long-term effects of oestrogen use on invasive breast cancer incidence, tumour characteristics, and mortality. We used Cox regression models to estimate hazard ratios (HRs) in the intention-to-treat population. This study is registered with ClinicalTrials.gov, number NCT00000611. FINDINGS After a median follow-up of 11·8 years (IQR 9·1-12·9), the use of oestrogen for a median of 5·9 years (2·5-7·3) was associated with lower incidence of invasive breast cancer (151 cases, 0·27% per year) compared with placebo (199 cases, 0·35% per year; HR 0·77, 95% CI 0·62-0·95; p=0·02) with no difference (p=0·76) between intervention phase (0·79, 0·61-1·02) and post-intervention phase effects (0·75, 0·51-1·09). In subgroup analyses, we noted breast cancer risk reduction with oestrogen use was concentrated in women without benign breast disease (p=0·01) or a family history of breast cancer (p=0·02). In the oestrogen group, fewer women died from breast cancer (six deaths, 0·009% per year) compared with controls (16 deaths, 0·024% per year; HR 0·37, 95% CI 0·13-0·91; p=0·03). Fewer women in the oestrogen group died from any cause after a breast cancer diagnosis (30 deaths, 0·046% per year) than did controls (50 deaths, 0·076%; HR 0·62, 95% CI 0·39-0·97; p=0·04). INTERPRETATION Our findings provide reassurance for women with hysterectomy seeking relief of climacteric symptoms in terms of the effects of oestrogen use for about 5 years on breast cancer incidence and mortality. However, our data do not support use of oestrogen for breast cancer risk reduction because any noted benefit probably does not apply to populations at increased risk of such cancer. FUNDING US National Heart, Lung, and Blood Institute; Wyeth.


Obstetrics & Gynecology | 2005

Menopausal symptoms and treatment-related effects of estrogen and progestin in the women's health initiative

Vanessa M. Barnabei; Barbara B. Cochrane; Aaron K. Aragaki; Ingrid Nygaard; R.Stan Williams; Peter G. McGovern; Ronald L. Young; Ellen Wells; Mary Jo O'Sullivan; Bertha Chen; Robert S. Schenken; Susan R. Johnson

OBJECTIVE: To estimate the effects of estrogen plus progestin (E+P) therapy on menopausal symptoms, vaginal bleeding, gynecologic surgery rates, and treatment-related adverse effects in postmenopausal women. METHODS: Randomized, double-blind, placebo-controlled trial of 16,608 postmenopausal women, ages 50–79 (mean ± standard deviation 63.3 ± 7.1) years, with intact uterus, randomized to one tablet per day containing 0.625 mg conjugated equine estrogens plus 2.5 mg medroxyprogesterone acetate (n = 8,506) or placebo (n = 8,102), and followed for a mean of 5.6 years. Change in symptoms and treatment-related effects were analyzed at year 1 in all participants. Bleeding and gynecologic surgery rates were analyzed through study close-out. RESULTS: Baseline symptoms did not differ between the treatment groups. More women assigned to E+P than placebo reported relief of hot flushes (85.7% versus 57.7%, respectively; odds ratio 4.40; 95% confidence interval 3.40–5.71), night sweats (77.6% versus 57.4%; 2.58; 2.04–3.26), vaginal or genital dryness (74.1% versus 54.6%; 2.40; 1.90–3.02), joint pain or stiffness (47.1% versus 38.4%; 1.43; 1.24–1.64), and general aches or pains (49.3% versus 43.7%; 1.25; 1.08–1.44). Women asymptomatic at baseline who were assigned to E+P more often developed breast tenderness (9.3% versus 2.4%, respectively; 4.26; 3.59–5.04), vaginal or genital discharge (4.1% versus 1.0%; 4.47; 3.44–5.81), vaginal or genital irritation (4.2% versus 2.8%; 1.52; 1.27–1.81), and headaches (5.8% versus 4.7%; 1.26; 1.08–1.46) than women on placebo. Estrogen plus progestin treatment prevented the onset of new musculoskeletal symptoms. Vaginal bleeding was reported by 51% of women on E+P and 5% of women on placebo at 6 months; most bleeding was reported as spotting. Gynecologic surgeries (hysterectomy and dilation and curettage) were performed more frequently in women assigned to E+P (3.1% versus 2.5% for hysterectomy, hazard ratio = 1.23, P = .026; 5.4% versus 2.4% for dilation and curettage, hazard ratio = 2.23, P < .001). CONCLUSION: Estrogen plus progestin relieved some menopausal symptoms, such as vasomotor symptoms and vaginal or genital dryness, but contributed to treatment-related effects, such as bleeding, breast tenderness, and an increased likelihood of gynecologic surgery. LEVEL OF EVIDENCE: I


The Journal of Neuroscience | 2007

Expression profiling of Huntington's disease models suggests that brain-derived neurotrophic factor depletion plays a major role in striatal degeneration.

Andrew D. Strand; Zachary C. Baquet; Aaron K. Aragaki; Peter Holmans; Lichuan Yang; Carine Cleren; M. Flint Beal; Lesley Jones; Charles Kooperberg; James M. Olson; Kevin R. Jones

Many pathways have been proposed as contributing to Huntingtons disease (HD) pathogenesis, but generally the in vivo effects of their perturbation have not been compared with reference data from human patients. Here we examine how accurately mechanistically motivated and genetic HD models recapitulate the striatal gene expression phenotype of human HD. The representative genetic model was the R6/2 transgenic mouse, which expresses a fragment of the huntingtin protein containing a long CAG repeat. Pathogenic mechanisms examined include mitochondrial dysfunction; profiled in 3-nitropropionic acid-treated rats, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-treated mice, and PGC-1α knock-out mice; and depletion of brain-derived neurotrophic factor (BDNF) using heterozygous and forebrain-specific BDNF-knock-out mice (BDNF HET , Emx-BDNF KO ). Based on striatal gene expression, we find the BDNF models, both heterozygous and homozygous knock-outs, to be more like human HD than the other HD models. This implicates reduced trophic support as a major pathway contributing to striatal degeneration in HD. Because the majority of striatal BDNF is synthesized by cortical neurons, the data also imply that cortical dysfunction contributes to HDs hallmark effects on the basal ganglia. Finally, the results suggest that striatal lesions caused by mitochondrial toxins may arise via pathways different from those that drive neurodegeneration in HD. Based on these findings, we present a testable model of HD pathogenesis that, unlike most models, begins to account for regional specificity in human HD and the absence of such specificity in genetic mouse models of HD.


Gastroenterology | 2013

Identification of genetic susceptibility loci for colorectal tumors in a genome-wide meta-analysis

Ulrike Peters; Fredrick R. Schumacher; Carolyn M. Hutter; Aaron K. Aragaki; John A. Baron; Sonja I. Berndt; Stéphane Bézieau; Hermann Brenner; Katja Butterbach; Bette J. Caan; Peter T. Campbell; Christopher S. Carlson; Graham Casey; Andrew T. Chan; Jenny Chang-Claude; Stephen J. Chanock; Lin Chen; Gerhard A. Coetzee; Simon G. Coetzee; David V. Conti; Keith R. Curtis; David Duggan; Todd L. Edwards; Charles S. Fuchs; Steven Gallinger; Edward Giovannucci; Stephanie M. Gogarten; Stephen B. Gruber; Robert W. Haile; Tabitha A. Harrison

BACKGROUND & AIMS Heritable factors contribute to the development of colorectal cancer. Identifying the genetic loci associated with colorectal tumor formation could elucidate the mechanisms of pathogenesis. METHODS We conducted a genome-wide association study that included 14 studies, 12,696 cases of colorectal tumors (11,870 cancer, 826 adenoma), and 15,113 controls of European descent. The 10 most statistically significant, previously unreported findings were followed up in 6 studies; these included 3056 colorectal tumor cases (2098 cancer, 958 adenoma) and 6658 controls of European and Asian descent. RESULTS Based on the combined analysis, we identified a locus that reached the conventional genome-wide significance level at less than 5.0 × 10(-8): an intergenic region on chromosome 2q32.3, close to nucleic acid binding protein 1 (most significant single nucleotide polymorphism: rs11903757; odds ratio [OR], 1.15 per risk allele; P = 3.7 × 10(-8)). We also found evidence for 3 additional loci with P values less than 5.0 × 10(-7): a locus within the laminin gamma 1 gene on chromosome 1q25.3 (rs10911251; OR, 1.10 per risk allele; P = 9.5 × 10(-8)), a locus within the cyclin D2 gene on chromosome 12p13.32 (rs3217810 per risk allele; OR, 0.84; P = 5.9 × 10(-8)), and a locus in the T-box 3 gene on chromosome 12q24.21 (rs59336; OR, 0.91 per risk allele; P = 3.7 × 10(-7)). CONCLUSIONS In a large genome-wide association study, we associated polymorphisms close to nucleic acid binding protein 1 (which encodes a DNA-binding protein involved in DNA repair) with colorectal tumor risk. We also provided evidence for an association between colorectal tumor risk and polymorphisms in laminin gamma 1 (this is the second gene in the laminin family to be associated with colorectal cancers), cyclin D2 (which encodes for cyclin D2), and T-box 3 (which encodes a T-box transcription factor and is a target of Wnt signaling to β-catenin). The roles of these genes and their products in cancer pathogenesis warrant further investigation.

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JoAnn E. Manson

Brigham and Women's Hospital

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Rowan T. Chlebowski

City of Hope National Medical Center

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Ross L. Prentice

Fred Hutchinson Cancer Research Center

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Garnet L. Anderson

Fred Hutchinson Cancer Research Center

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Charles Kooperberg

Fred Hutchinson Cancer Research Center

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Karen C. Johnson

University of Tennessee Health Science Center

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Jacques E. Rossouw

National Institutes of Health

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