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1.
Horm Cancer ; 7(2): 127-36, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26902826

ABSTRACT

Prior reports identify higher serum concentrations of estrogens and androgens as risk factors for breast cancer, but steroids in nipple aspirate fluid (NAF) may be more related to risk. Incident breast cancer cases and mammography controls were recruited. Sex steroids were measured in NAF from the unaffected breasts of cases and one breast of controls. Menopausal status and menstrual cycle phase were determined. NAF steroids were purified by HPLC and quantified by immunoassays. Conditional logistic regression models were used to examine associations between NAF hormones and case-control status. NAF samples from 160 cases and 157 controls were evaluable for hormones. Except for progesterone and dehydroepiandrosterone (DHEA), the NAF and serum concentrations were not significantly correlated. NAF estradiol and estrone were not different between cases and controls. Higher NAF (but not serum) DHEA concentrations were associated with cases, particularly among estrogen receptor (ER)-positive cases (NAF odds ratio (OR) = 1.18, 95 % confidence interval (CI) 1.02, 1.36). NAF DHEA was highly correlated with NAF estradiol and estrone but not with androstenedione or testosterone. Higher progesterone concentrations in both NAF and serum were associated with a lower risk of ER-negative cancer (NAF OR = 0.69, 95 % CI 0.51, 0.92). However, this finding may be explained by case-control imbalance in the number of luteal phase subjects (2 cases and 19 controls). The significantly higher concentration of DHEA in NAF of cases and its correlation with NAF estradiol indicates a potentially important role of this steroid in breast cancer risk; however, the negative association of progesterone with risk is tentative.


Subject(s)
Breast Neoplasms/etiology , Gonadal Steroid Hormones/analysis , Gonadal Steroid Hormones/blood , Nipple Aspirate Fluid/chemistry , Adult , Aged , Breast Neoplasms/blood , Breast Neoplasms/metabolism , Case-Control Studies , Female , Humans , Logistic Models , Middle Aged , Risk Factors
2.
Cancer Chemother Pharmacol ; 76(6): 1235-46, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26560487

ABSTRACT

PURPOSE: Women at high risk of breast cancer and those with carcinoma in situ need non-toxic, well-tolerated preventive interventions. One promising approach is drug delivery through the breast skin (local transdermal therapy, LTT). Our goal was to test novel drugs for LTT, to establish that LTT is applicable to non-steroidal drugs. METHODS: Athymic nude rats were treated with oral tamoxifen, transdermal 4-hydroxytamoxifen (4-OHT) or endoxifen gel applied daily to the axillary mammary gland for 6 weeks (Study 1). Study 2 was identical to Study 1, testing transdermal telapristone acetate (telapristone) gel versus subcutaneous implant. At euthanasia, mammary glands and blood were collected. In Study 3, consenting women requiring mastectomy were randomized to diclofenac patch applied to the abdomen or the breast for 3 days preoperatively. At surgery, eight tissue samples per breast were collected from predetermined locations, along with venous blood. Drug concentrations were measured using liquid chromatography-tandem mass spectroscopy. RESULTS: Mammary tissue concentrations of 4-OHT, endoxifen, and telapristone were significantly higher in the axillary glands of the gel-treated animals, compared to inguinal glands or to systemically treated animals. Plasma concentrations were similar in gel and systemically treated animals. The clinical trial showed significantly higher mammary concentrations when diclofenac was applied to the breast skin versus the abdominal skin, but concentrations were variable. CONCLUSIONS: These results demonstrate that lipophilic drugs can be developed for LTT; although the nude rat is suitable for testing drug permeability, delivery is systemic. In human, however, transdermal application to the breast skin provides local delivery.


Subject(s)
Antineoplastic Agents/therapeutic use , Breast Neoplasms/prevention & control , Breast/drug effects , Carcinoma, Intraductal, Noninfiltrating/drug therapy , Administration, Cutaneous , Administration, Oral , Adult , Animals , Antineoplastic Agents/administration & dosage , Breast/pathology , Diclofenac/administration & dosage , Diclofenac/therapeutic use , Drug Evaluation, Preclinical/methods , Female , Gels , Humans , Mammary Glands, Animal/drug effects , Middle Aged , Norpregnadienes/administration & dosage , Norpregnadienes/pharmacology , Outcome Assessment, Health Care , Pilot Projects , Preoperative Period , Random Allocation , Rats, Nude , Tamoxifen/administration & dosage , Tamoxifen/analogs & derivatives , Tamoxifen/pharmacology
3.
BMC Cancer ; 15: 878, 2015 Nov 09.
Article in English | MEDLINE | ID: mdl-26552376

ABSTRACT

BACKGROUND: Despite demonstrated efficacy, acceptance of selective estrogen receptor modulators (SERMs), such as tamoxifen, for breast cancer risk reduction remains low. Delivering SERMs via local transdermal therapy (LTT) could significantly reduce systemic effects and therefore may increase acceptance. We aim to assess women's knowledge of breast cancer prevention medications and views on LTT of SERMs. METHODS: Focus groups were conducted with healthy women identified through the comprehensive breast center of a large urban cancer institution. Group discussions covered risk perceptions, knowledge of and concerns about risk reducing medications. Participants reported their perceived risk for breast cancer (average, below/above average), preference for SERMs in a pill or gel form, risk factors, and prior physician recommendations regarding risk-reducing medicines. Participants' breast cancer risk was estimated using tools based on the Gail Model. Trained personnel examined all qualitative results systematically; risk perceptions and preferred method of medication delivery were tallied quantitatively. RESULTS: Four focus groups (N = 32) were conducted. Most participants had at least a college degree (78.2 %) and were of European (50 %) or African ancestry (31 %). The majority (72 %) were at elevated risk for breast cancer; approximately half of these women perceived themselves to be at elevated risk. Few participants had prior knowledge of preventive medications. The women noted a number of concerns about LTT, including dosage, impact on day-to-day life, and side effects; nonetheless, over 90 % of the women stated they would prefer LTT to a pill. CONCLUSION: Awareness of preventive medications was low even in a highly educated sample of high-risk women. If given a choice in the route of administration, most women preferred a gel to a pill, anticipating fewer side effects. Future work should focus on demonstrating equivalent efficacy and reduced toxicity of topical over oral medications and on raising awareness of chemopreventive options for breast cancer.


Subject(s)
Breast Neoplasms/drug therapy , Breast Neoplasms/epidemiology , Tamoxifen/administration & dosage , Women's Health , Administration, Cutaneous , Administration, Oral , Adult , Aged , Awareness , Breast Neoplasms/pathology , Female , Focus Groups , Humans , Middle Aged , Risk Factors
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