Biomedical subjects

Anne McTiernan

Publications and source records attributed to Anne McTiernan.

At least 19 recordsLinked to original sources

PubMed2007

Exercise and biomarkers for cancer prevention studies.

The International Agency for Research on Cancer estimates that 25% of cancer cases worldwide are caused by overweight or obesity and a sedentary lifestyle. These lifestyle patterns may increase cancer risk by several mechanisms including increased estrogens and testosterone, hyperinsulinemia and insulin resistance, increased inflammation, and depressed immune function. Several randomized clinical trials have shown that physical activity and diet interventions can change biomarkers of cancer risk. In a controlled physical activity trial, we found decreases in serum estrogen, testosterone, and insulin in overweight, sedentary postmenopausal women with a 1-y exercise program consisting of moderate-intensity aerobic exercise, 45 min/d, 5 d/wk. In another controlled trial in middle-aged to older persons, we found that a 1-y exercise intervention of 60 min/d, 6 d/wk, reduced colon crypt cell proliferation in men who adhered closely to the program. Only 1 trial, the Women's Health Initiative Dietary Modification Trial, has published results of a dietary intervention on breast cancer incidence and reported a statistically nonsignificant 9% reduction in invasive breast cancer incidence in postmenopausal women following a low-fat dietary pattern for 8-12 y. Other trials under way are testing effects of weight loss, physical activity, and dietary patterns on other cancer biomarkers. The NCI-funded Transdisciplinary Research on Energetics and Cancer centers are exploring novel research into mechanisms linking energy balance with cancer risk and prevention. The worldwide trends toward increasing overweight and obesity and decreasing physical activity may lead to an increased incidence of several cancers unless other means of risk reduction counteract these effects. Thus, adoption of lifestyle changes by individuals and populations may have a large impact on the future incidence of cancer.

Biomarkers↗

PubMed2006

Associations between the CYP17, CYPIB1, COMT and SHBG polymorphisms and serum sex hormones in post-menopausal breast cancer survivors.

Several polymorphisms have been identified in genes that code for enzymes involved with estrogen biosynthesis and metabolism. Little is known about the functional relevance of these polymorphisms on sex hormones in vivo. We examined the association between CYP17, CYP1B1, COMT or SHBG genotypes and serum concentrations of estrone, estradiol, free estradiol, sex hormone-binding globulin (SHBG), testosterone, free testosterone and dehyroepiandrosterone in 366 post-menopausal breast cancer survivors in New Mexico, California and Washington. Hormone levels were determined by high performance liquid chromatography and radioimmunoassay in blood drawn approximately 2 years post-diagnosis. We used generalized linear regression to calculate mean hormone levels by genotype, adjusting for age, race/ethnicity, stage, study site, tamoxifen use, number of remaining ovaries, hormone therapy use, marital status and BMI. No associations were observed between any of the genotypes and sex hormones when analyzing the main effects. In subgroup analyses, androgen levels of Hispanic women with the variant (A2) CYP17 genotype were 46-87% higher than those of women with the wild-type; androgen levels were 13-20% lower in non-Hispanic whites with the variant genotype; no difference by genotype was observed for African-American women. Current tamoxifen users with the variant asn(327) SHBG genotype had 81% higher serum SHBG and 39% lower free testosterone concentrations than women with the wild-type genotype. Non-tamoxifen users with the variant SHBG allele had elevated free estradiol levels. These results provide little evidence that the CYP17, CYP1B1, and COMT polymorphisms are associated with different sex hormone levels in post-menopausal breast cancer survivors.

Adolescent↗

PubMed2006

Randomized trial of exercise in sedentary middle aged women: effects on quality of life.

Increasing physical activity is currently considered to be a possible prevention strategy for cancer, obesity, and cardiovascular disease, either alone or in combination with dietary changes. This paper presents results of a randomized trial of moderate-to-vigorous intensity exercise in middle aged, sedentary women; specifically, we report changes in and correlates of quality of life and functional status of this exercise intervention program for both the short (three months) and longer term (12 months). The intervention group showed a significant increase in Mental Health score from baseline to 3 months (p < .01), significantly greater than the change in the control group at 3 months (p < .01). A similar trend among exercisers was observed for the General Health score (p < .01), and this finding was significantly greater than the change in control group at 3 months (p = .01). Change in Social Support - Affection were predictors of the changes in quality of life variables. This study documented improvements in quality of life and general functioning that occurred as a result of participating in an exercise intervention in sedentary middle-aged women.

Journal Article↗

PubMed2006

The association between aspirin use and the incidence of colorectal cancer in women.

The purpose of this study was to test the hypothesis that aspirin use is associated with a decreased risk of incident colorectal cancer. From the Women's Health Initiative, 91,574 participants between the ages of 50 and 79 years at baseline in 1993-1998 provided details on aspirin use via interview using a standardized questionnaire and were subsequently followed annually for incident colorectal cancer during a period of over 6 years. For those persons who reported aspirin use, the type of compound, dose, and duration of use were recorded. Medical histories suggestive of colorectal cancers at the annual update were verified by medical record and pathology report review by trained local physician adjudicators. There were 631 confirmed cases of invasive cancer of the colon or rectum. There was no significant association between any aspirin use and risk for incident colorectal cancer (hazard ratio = 0.96, 95% confidence interval: 0.8, 1.2). Moreover, with no aspirin use as the referent category, there were no significant associations for duration of aspirin intake by category (< 1, 1- < 2, 2- < 3, 3- < 4, 4- < 5, and > or = 5 years) or for daily dosage by category (< 165, 165- < 300, 300- < 495, or > or = 495 mg).

Aged↗

PubMed2006

Prior hormone therapy and breast cancer risk in the Women's Health Initiative randomized trial of estrogen plus progestin.

OBJECTIVES: To assess the extent to which prior hormone therapy modifies the breast cancer risk found with estrogen plus progestin (E+P) in the Women's Health Initiative (WHI) randomized trial. METHODS: Subgroup analyses of prior hormone use on invasive breast cancer incidence in 16,608 postmenopausal women in the WHI randomized trial of E+P over an average 5.6 years of follow-up. RESULTS: Small but statistically significant differences were found between prior HT users and non-users for most breast cancer risk factors but Gail risk scores were similar. Duration of E+P use within the trial (mean 4.4 years, S.D. 2.0) did not vary by prior use. Among 4311 prior users, the adjusted hazard ratio (HR) for E+P versus placebo was 1.96 (95% confidence interval [CI]: 1.17-3.27), significantly different (p=0.03) from that among 12,297 never users (HR 1.02; 95% CI: 0.77-1.36). The interaction between study arm and follow-up time was significant overall (p=0.01) and among never users (p=0.02) but not among prior users (p=0.10). The cumulative incidence over time for the E+P and placebo groups appeared to cross after about 3 years in prior users, and after about 5 years in women with no prior use. No interaction was found with duration (p=0.08) or recency of prior use (p=0.17). Prior hormone use significantly increased the E+P hazard ratio for larger, more advanced tumors. CONCLUSION: A safe interval for combined hormone use could not be reliably defined with these data. However, the significant increase in breast cancer risk in the trial overall after only 5.6 years of follow-up, initially concentrated in women with prior hormone exposure, but with increasing risk over time in women without prior exposure, suggests that durations only slightly longer than those in the WHI trial are associated with increased risk of breast cancer. Longer-term exposure and follow-up data are needed.

Aged↗

PubMed2006

Psychometric evaluation of the Brief Cancer Impact Assessment among breast cancer survivors.

OBJECTIVES: The increasing number of cancer survivors brings greater attention to the biopsychosocial impact of surviving cancer. Instruments exist that measure quality of life (QOL), symptoms, and specific types of functioning after cancer; however, a reliable and valid assessment of the perceived impact of cancer (IOC) on the life plans and activities of cancer survivors has been missing. This study evaluated the psychometric properties of the 16-item Brief Cancer Impact Assessment (BCIA). METHODS: Factor analysis with Promax oblique rotation established the factor structure of the BCIA in 783 ethnically diverse breast cancer survivors, >or=2 years after diagnosis. Construct validity was assessed by comparing factor-based scale means by demographic and treatment characteristics, and correlating scales with psychosocial and health-related QOL scales. RESULTS: Factor analysis revealed four factors measuring the IOC on caregiving and finances, exercise and diet behaviors, social and emotional functioning, and religiosity. Scale scores differed by demographic and treatment characteristics according to expectations, and the pattern of correlations with psychosocial and health-related QOL generally supported the construct validity of the scales. CONCLUSION: Including the BCIA with measures of QOL, symptoms, and functioning will allow researchers to gain a more comprehensive assessment of the biopsychosocial IOC in survivors.

Adult↗

PubMed2006

An association between a common variant (G972R) in the IRS-1 gene and sex hormone levels in post-menopausal breast cancer survivors.

Insulin receptor substrate-1 (IRS-1) is a key downstream signaling molecule common to both the insulin and IGF signaling pathways that can interact with the estrogen pathway to regulate breast cell growth. We investigated whether a putative functional variant for IRS-1 (G972R) influences circulating levels of sex hormones, sex hormone binding globulin (SHBG), C-peptide, and insulin-like growth factor 1 (IGF-1) levels among post-menopausal African-American and non-Hispanic white breast cancer patients enrolled in the Health, Eating, Activity, and Lifestyle (HEAL) Study. Circulating levels of sex hormones and growth factors can influence breast cancer recurrence and survival. Serum estrone, estradiol, testosterone, SHBG, IGF-1 and C-peptide were measured in 468 patients at 30+ months post diagnosis. Non-protein bound hormone levels (free estradiol, free testosterone) were calculated. In African-American patients, the IRS-1 variant was associated with increased serum levels of estrone (p = 0.02), free estradiol (p = 0.04), total testosterone (p = 0.04), free testosterone (p = 0.006) and decreased levels of sex hormone-binding globulin (p = 0.02). No association was present for white patients. Our findings provide suggestive evidence that IRS-1 G972R variant may be associated with circulating levels of sex hormones and SHBG in African American breast cancer survivors.

Black or African American↗

PubMed2006

Statin use and breast cancer: prospective results from the Women's Health Initiative.

BACKGROUND: Despite experimental observations suggesting that 3-hydroxy-3-methylglutaryl coenzyme A inhibitors (statins) have antitumor activity, clinical studies have reached mixed conclusions about the relationship between statin use and breast cancer risk. METHODS: To investigate associations between potency, duration of use, and type of statin used and risk of invasive breast cancer, we examined data for 156,351 postmenopausal women who were enrolled in the Women's Health Initiative. Information was collected on breast cancer risk factors and on the use of statins and other lipid-lowering drugs. Cox proportional hazards regression was used to calculate hazard ratios (HRs) with 95% confidence intervals (CIs). Statistical tests were two-sided. RESULTS: Over an average follow-up of 6.7 years, 4383 invasive breast cancers were confirmed by medical record and pathology report review. Statins were used by 11,710 (7.5%) of the cohort. Breast cancer incidence was 4.09 per 1000 person-years (PY) among statin users and 4.28 per 1000 PY among nonusers. In multivariable models, the hazard ratio of breast cancer among users of any statin, compared with nonusers, was 0.91 (95% CI = 0.80 to 1.05, P = .20). There was no trend in risk by duration of statin use, with HR = 0.80 (95% CI = 0.63 to 1.03) for < 1 year of use, HR = 0.99 (95% CI = 0.80 to 1.23) for 1- < 3 years of use, and HR = 0.94 (95% CI = 0.75 to 1.18) for > or = 3 years of use. Hydrophobic statins (i.e., simvastatin, lovastatin, and fluvastatin) were used by 8106 women, and their use was associated with an 18% lower breast cancer incidence (HR = 0.82, 95% CI = 0.70 to 0.97, P = .02). Use of other statins (i.e., pravastatin and atorvastatin) or nonstatin lipid-lowering agents was not associated with breast cancer incidence. CONCLUSIONS: Overall statin use was not associated with invasive breast cancer incidence. Our finding that use of hydrophobic statins may be associated with lower breast cancer incidence suggests possible within-class differences that warrant further evaluation.

Aged↗

PubMed2006

Exercise and side effects among 749 patients during and after treatment for cancer: a University of Rochester Cancer Center Community Clinical Oncology Program Study.

GOALS: Despite advances in cancer treatment and symptom management, many patients experience side effects from cancer treatments that cause suffering and impair quality of life (QOL). Exercise is a method for enhancing QOL among cancer patients that shows promise in reducing side effects. However, patient participation in exercise is not well defined. We report on exercise participation during and within 6 months after chemotherapy and radiation therapy, the association of exercise with treatment side effects, and the communication between physicians and patients about exercise in a large (N = 749) nationwide sample of cancer patients. PATIENTS AND METHODS: Participants completed measures that included questions concerning exercise during and after treatment, treatment side effects, and communication with physicians regarding exercise. Questionnaires were administered 2 weeks and 6 months after completion of therapy. RESULTS: Almost half of the 749 participating patients reported exercising while undergoing chemotherapy and/or radiation, and more than half reported exercising during the 6 months after treatment. Exercise was associated with less severe side effects during and after treatment (p < or = 0.050). More than 30% of patients reporting exercise did not discuss exercise with a physician; however, those who did were more likely to talk with their oncologist than with their primary care provider. CONCLUSIONS: Cancer patients report exercising and appear amenable to attempting exercise during and within 6 months after treatment. Research is needed to assess (1) the frequency, intensity, duration, and mode of exercise; (2) randomized controlled trials with exercise and its influence on treatments and side effects; and (3) physician-patient communication regarding exercise during cancer treatment.

Academic Medical Centers↗

PubMed2006

Cutaneous melanoma in postmenopausal women after nonmelanoma skin carcinoma: the Women's Health Initiative Observational Study.

BACKGROUND: An elevated risk for cutaneous melanoma has been reported in individuals with nonmelanoma skin carcinoma (NMSC), but to the authors' knowledge, this association has not been prospectively studied in a large, multigeographic population of postmenopausal women. METHODS: The association between NMSC and the incidence of cutaneous melanoma was assessed in the Women's Health Initiative Observational Study involving 67,030 non-Hispanic white postmenopausal women ages 50-79 years and who were free of prior other cancers at baseline. Cancer history, demographics, and previous and current risk exposures were determined by questionnaires at baseline and follow-up. Participants' reports of incident cutaneous melanoma collected annually were confirmed by physician review of medical records. Cox proportional hazards analyses were used to assess the relation of prior NMSC with incident cutaneous melanoma. RESULTS: In age-adjusted analysis, women with a history of NMSC but no other malignancy (n = 5552) were found to be 2.41 times more likely to develop cutaneous melanoma over a mean 6.5 years compared with women who had no history of NMSC (95% confidence interval [95% CI], 1.82-3.20). In a multivariate analysis, women with a history of NMSC and no other cancer history at baseline were 1.70 times more likely to develop cutaneous melanoma compared with women without NMSC (95% CI, 1.18-2.44). CONCLUSION: The results of the current study provide evidence and further defines the magnitude of increased risk for cutaneous melanoma in postmenopausal non-Hispanic white women with a history of NMSC.

Aged↗

PubMed2006

A phase I/II study of doxorubicin, ifosfamide, etoposide and interval methotrexate in patients with poor prognosis osteosarcoma.

BACKGROUND: The prognosis for patients with metastatic or axial-skeletal osteosarcoma is poor. A phase I/II study was conducted of intensive chemotherapy with interval methotrexate, to assess the feasibility, response rate and toxicity in this group of patients. PATIENTS AND METHODS: Thirteen patients, median age 18 (range: 8-34), with metastatic or axial-skeletal osteosarcoma were treated with ifosfamide 2.5 g/m(2), etoposide 150 mg/m(2), and doxorubicin 20 mg/m(2) on days 1-3, every 21 days, with interval methotrexate 12 g/m(2) given on day 14, for a maximum of eight cycles. Surgery to the primary was considered after four cycles for those with operable disease, or together with metastatic disease at completion of chemotherapy in those with inoperable tumours. RESULTS: A total of 85 cycles were given, median 6 per patient (range: 4-8). Only 6 of the 13 patients completed all 8 cycles of chemotherapy. Forty-eight cycles (56%) required a dose reduction. The principal toxicity was myelosuppression, with a median nadir neutrophil count of 0.1 (range: 0-4.1). Grade 3 or 4 infection was seen in 41 cycles (48%). Histological response was assessable in seven patients, all of whom achieved a >or=90% necrosis. Radiological response rate, evaluable in seven patients with lung metastases, was 43%. All but one patient has had subsequent disease progression or relapse, with a median event free survival of 13 months (range: 5-53). CONCLUSION: This regimen was associated with responses, but these were not sustained. Substantial toxicity was seen, preventing optimal delivery. More effective, less toxic regimens are needed in this group of patients.

Adolescent↗

PubMed2006

Psychometric properties of a tool for measuring hormone-related symptoms in breast cancer survivors.

Hormone-related symptoms are common in breast cancer survivors and many aspects of these symptoms are currently under study. Reliable and valid assessment tools are needed to successfully study hormone-related symptoms in breast cancer survivors; however, no gold standard currently exists for measuring these symptoms. This study evaluated the psychometric properties of a shortened version of the Breast Cancer Prevention Trial (BCPT) symptom checklist in a sample of 803 breast cancer survivors. Principal factor analysis with Promax oblique rotation revealed a five-factor structure, identifying five separate hormone-related symptoms scales: vasomotor symptoms, urinary incontinence, cognitive/mood changes, vaginal symptoms, and weight gain/appearance concern. Hormone-related symptom scale scores differed by demographic and clinical characteristics according to expectations, suggesting that these five scales from the shortened BCPT checklist are reasonably reliable and valid. Symptom scale scores were only weakly correlated with health-related quality of life scores; however, the pattern of results generally supported the validity of the symptom scales. This study adds to the evidence that breast cancer survivors experience a significant number of hormone-related symptoms. Future clinical trials and quality of life and symptom management intervention studies would benefit from accurate assessment of hormone-related symptoms with the five scales from the shortened BCPT checklist.

Adult↗

PubMed2006

Moderate-intensity exercise reduces the incidence of colds among postmenopausal women.

PURPOSE: Our aim was to assess the effect of a moderate-intensity, year-long exercise program on the risk of colds and other upper respiratory tract infections in postmenopausal women. SUBJECTS: A total of 115 overweight and obese, sedentary, postmenopausal women in the Seattle area participated. METHODS: Participants were randomly assigned to the moderate-intensity exercise group or the control group. The intervention consisted of 45 minutes of moderate-intensity exercise 5 days per week for 12 months. Control participants attended once-weekly, 45-minute stretching sessions. Questionnaires asking about upper respiratory tract infections in the previous 3 months were administered quarterly during the course of the year-long trial. Poisson regression was used to estimate the effect of exercise on colds and other upper respiratory tract infections. RESULTS: Over 12 months, the risk of colds decreased in exercisers relative to stretchers (P = .02): In the final 3 months of the study, the risk of colds in stretchers was more than threefold that of exercisers (P = .03). Risk of upper respiratory tract infections overall did not differ (P = .16), yet may have been biased by differential proportions of influenza vaccinations in the intervention and control groups. CONCLUSIONS: This study suggests that 1 year of moderate-intensity exercise training can reduce the incidence of colds among postmenopausal women. These findings are of public health relevance and add a new facet to the growing literature on the health benefits of moderate exercise.

Aged↗

PubMed2006

Relation of BMI and physical activity to sex hormones in postmenopausal women.

OBJECTIVE: Levels of estrogen, androgen, and prolactin have been related to risk of postmenopausal breast cancer. However, the determinants of these hormone concentrations are not established. The purpose of this study was to examine correlates of endogenous sex hormones. RESEARCH METHODS AND PROCEDURES: Associations among adiposity, physical activity, and diet and concentrations of estradiol, free estradiol, estrone, testosterone, free testosterone, sex hormone-binding globulin (SHBG), androstenedione, dehydroepiandrosterone, dehydroepiandrosterone sulfate, and prolactin were evaluated in 267 postmenopausal women randomly selected from the Women's Health Initiative Dietary Modification Trial. RESULTS: In multiple regression analyses on log-transformed hormones, BMI was positively associated with estrone (beta = 0.031, p < 0.001), estradiol (beta = 0.048, p < 0.001), free estradiol (beta = 0.062, p < 0.001), free testosterone (beta = 0.017, p = 0.02), and prolactin (beta = 0.012, p = 0.02) and negatively associated with SHBG (beta = -0.02, p = 0.001). Total physical activity (metabolic equivalent tasks per week) was negatively associated with concentrations of estrone, estradiol, and androstenedione (beta = -0.006, -0.007, and -0.005, respectively, all p < or = 0.05). Using a composite variable of BMI and physical activity dichotomized by median values, women with high BMI/low physical activity had a mean estrone concentration of 28.8 pg/mL, compared with 24.1, 19.9, and 18.4 pg/mL for women with high BMI/high physical activity, low BMI/low physical activity, and low BMI/high physical activity, respectively (p trend < 0.001). Similar trends were observed for estradiol and free estradiol and, in inverse, for SHBG. DISCUSSION: These associations may, in part, explain the positive associations between overweight/obesity and a sedentary lifestyle on breast cancer risk.

Aged↗

PubMed2006

Unmetabolized folic acid in plasma is associated with reduced natural killer cell cytotoxicity among postmenopausal women.

Folic acid (FA) supplements and food fortification are used to prevent neural tube defects and to lower plasma homocysteine. Through exposure to food fortification and vitamin supplement use, large populations in the United States and elsewhere have an unprecedented high FA intake. We evaluated dietary and supplemental intakes of folate and FA in relation to an index of immune function, natural killer cell (NK) cytotoxicity, among 105 healthy, postmenopausal women. Among women with a diet low in folate (<233 microg/d), those who used FA-containing supplements had significantly greater NK cytotoxicity (P = 0.01). However, those who consumed a folate-rich diet and in addition used FA supplements > 400 microg/d had reduced NK cytotoxicity compared with those consuming a low-folate diet and no supplements (P = 0.02). Prompted by this observation, we assessed the presence of unmetabolized FA in plasma as a biochemical marker of excess FA. Unmetabolized folic acid was detected in 78% of plasma samples from fasting participants. We found an inverse relation between the presence of unmetabolized FA in plasma and NK cytotoxicity. NK cytotoxicity was approximately 23% lower among women with detectable folic acid (P = 0.04). This inverse relation was stronger among women >or= 60 y old and more pronounced with increasing unmetabolized FA concentrations (P-trend = 0.002). Because of the increased intake of FA in many countries, our findings highlight the need for further studies on the effect of long-term high FA intake on immune function and health.

Diet↗

PubMed2006

A Phase II Nonrandomised Open-Label Study of Liposomal Daunorubicin (DaunoXome) in Advanced Soft Tissue Sarcoma.

Thirty four patients with advanced soft tissue sarcoma not previously treated with an anthracycline were treated with DaunoXome 100mg/m2 every 3 weeks. Thirty-three patients were evaluable for toxicity. Grade 3-4 neutropenia was seen in 20 patients (60.6%), complicated by febrile neutropenia in 2 (6.1%). Other grade 3 toxicities were rare. Among 32 patients assessable for response, one patient had a partial response, giving a response rate of 3.13% (95% confidence interval, 0.08-16.22%). Seven patients (21.9%) had stable disease, and 24 patients (75.0%) had disease progression. The median time to progression for all patients was 42 days (95% CI, 39-49) and the progression-free rate at 3 months was 12.5%. In conclusion, DaunoXome at this dose and schedule is well tolerated in patients with advanced soft tissue sarcoma, but is not associated with significant activity. Further studies at this dose and schedule cannot be recommended in this disease.

Journal Article↗

PubMed2006

Mammographic density correlation with Gail model breast cancer risk estimates and component risk factors.

BACKGROUND: The Gail model is a validated breast cancer risk assessment tool that is primarily based on nonmodifiable breast cancer risk factors. Conversely, mammographic breast density is strongly correlated with breast cancer risk and responds to risk-modifying interventions. The purpose of our study was to correlate mammographic density with breast cancer risk as calculated by the Gail model and to examine the relative association of each of the model covariates to mammographic density. METHODS: The study included 99 participants of the National Surgical Breast and Bowel Project P-1 trial, ages 36 to 74 years, all of whom had a mammogram and Gail model risk estimates done upon trial entry. Baseline mammograms were retrieved and digitized, and mammographic density was assessed by both subjective and computer-assisted objective measures. RESULTS: Mammographic density was 2-fold higher in women with a >15% lifetime risk of breast cancer compared with those with <15% risk, by all density assessment methods. This was equivalent to a 3% to 6% increase in density per 10% increase in risk. Gail model covariates that measured benign or premalignant breast tissue changes accounted for the majority (41%) of the relationship with increased mammographic density. Seven percent of density was not explained by risk factors included in the Gail model. CONCLUSIONS: The Gail model does not fully account for the association between breast density and calculated breast cancer risk. Because mammographic density is a modifiable marker, development of a breast cancer risk assessment tool that includes mammographic density could be beneficial for assessing individual risk.

Adult↗

PubMed2006

Effect of a 12-month exercise intervention on patterns of cellular proliferation in colonic crypts: a randomized controlled trial.

BACKGROUND: Colon crypt architecture and proliferation may be appropriate biomarkers for testing prevention interventions. A hypothesized mechanism for exercise-induced colon cancer risk reduction might be through alterations in colon crypt cell architecture and proliferation. METHODS: Healthy, sedentary participants with a colonoscopy within the previous 3 years were recruited through gastroenterology practices and media. We randomly assigned 100 women and 102 men, ages 40 to 75 years, to a control group or a 12-month exercise intervention of moderate-to-vigorous aerobic exercise, 60 minutes per day, 6 days per week, and assessed change in number and relative position of Ki67-stained cells in colon mucosal crypts. RESULTS: Exercisers did a mean 370 min/wk (men) and 295 min/wk (women) of exercise (seven dropped the intervention). In men, the mean height of Ki67-positive nuclei relative to total crypt height was related to amount of exercise, with changes from baseline of 0.0% (controls), +0.3% (exercisers <250 min/wk), -1.7% (exercisers 250-300 min/wk), and -2.4% (exercisers >300 min/wk; P(trend) = 0.03). In male exercisers whose cardiopulmonary fitness (V(O(2))max) increased >5%, the mean height of Ki67-positive nuclei decreased by 2% versus 0.9% in other exercisers, and versus no change in controls (P(trend) = 0.05). Similar trends were observed in other proliferation markers. In women, increased amount of exercise or V(O(2))max did not result in notable changes in proliferation markers. CONCLUSIONS: A 12-month moderate-to-vigorous intensity aerobic exercise intervention resulted in significant decreases in colon crypt cell proliferation indices in men who exercised a mean of >/=250 min/wk or whose V(O(2))max increased by >/=5%.

Adult↗