ABSTRACT
PURPOSE: Maintaining high adherence rates (session attendance and compliance) in exercise programs during breast cancer treatment can be challenging. We aimed to identify adherence rates and predictors to an exercise program during adjuvant breast cancer treatment. METHODS: Ninety-two patients with localized breast cancer undergoing chemotherapy were randomly assigned to an 18-week supervised moderate-to-high intensity aerobic and resistance exercise program, including two 1-hour sessions/week. Additionally, participants were asked to be physically active for at least 30 minutes/day on at least three other days. We report median percentages for attendance, compliance with the prescribed duration and intensity of aerobic and muscle strength exercises, and the exercise advice given. Predictors included in univariate and multivariable linear regression models were demographical, tumor- and treatment-related factors, constructs of the theory of planned behavior, psychological and physical factors. RESULTS: Patients attended 83% (interquartile range: 69-91%) of the supervised sessions. Compliance with the duration of aerobic exercise, high-intensity aerobic exercise (cycling at the ventilatory threshold), muscle strength exercises and the exercise advice were 88%(64-97%), 50%(22-82%), 84%(65-94%) and 61%(33%-79%), respectively. Education, radiotherapy, BMI and physical fatigue were important predictors of adherence to supervised exercise. Beliefs about planned behaviors were important predictors, especially for compliance with the exercise advice. CONCLUSIONS: Attendance to and compliance with an 18-week aerobic and strength exercise program were high. The lowest compliance was found for high-intensity supervised aerobic exercise. The identified predictors should be considered when designing or adapting exercise programs for patients with localized breast cancer to increase adherence. TRIAL REGISTRATION: Current Controlled Trials ISRCTN43801571 Dutch Trial Register NTR2138.
Subject(s)
Breast Neoplasms/psychology , Exercise , Patient Compliance , Adult , Antineoplastic Agents/therapeutic use , Body Mass Index , Breast Neoplasms/drug therapy , Breast Neoplasms/radiotherapy , Fatigue , Female , Humans , Linear Models , Middle Aged , Self EfficacyABSTRACT
BACKGROUND: Bcl-2/adenovirus E1B 19 kDa-interacting protein 3 (BNIP3) is a pro-apoptotic member of the Bcl-2 family induced under hypoxia. Low or absent expression has recently been described in human tumors, including gastrointestinal tumors, resulting in poor prognosis. Little is known about BNIP3 expression in invasive breast cancer. The aim of the present study was to investigate the expression of BNIP3 in invasive breast cancer at the mRNA and protein level in correlation with the hypoxic response and clinicopathological features. METHODS: In 40 cases of invasive breast cancer, BNIP3 mRNA in situ hybridization was performed on frozen sections with a digoxigenin labeled anti-BNIP3 probe. Paraffin embedded sections of the same specimens were used to determine protein expression of BNIP3, Hypoxia Inducible Factor 1 alpha (HIF-1alpha) and its downstream targets Glucose Transporter 1 (Glut-1) and Carbonic Anhydrase (CAIX) by immunohistochemistry. RESULTS: BNIP3 mRNA was expressed in 16/40 (40%) of the cases and correlated with BNIP3 protein expression (p = 0.0218). Neither BNIP3 protein nor mRNA expression correlated with expression of HIF-1alpha expression or its downstream targets. Tumors which showed loss of expression of BNIP3 had significantly more often lymph node metastases (82% vs 39%, p = 0.010) and showed a higher mitotic activity index (p = 0.027). BNIP3 protein expression was often nuclear in normal breast, but cytoplasmic in tumor cells. CONCLUSION: BNIP3 expression is lost in a significant portion of invasive breast cancers, which is correlated with poor prognostic features such as positive lymph node status and high proliferation, but not with the hypoxic response.