The insulin-like growth factor system is modulated by exercise in breast cancer survivors: a systematic review and meta-analysis Meneses-Echávez, José F. González Jiménez, Emilio Schmidt Río Valle, Jacqueline Correa-Bautista, Jorge Enrique Izquierdo Redín, Mikel Ramírez-Vélez, Robinson Breast cancer Exercise Insulin-Like Growth Factor Binding Proteins Tumor Microenvironment Abbreviations: CI, Confidence interval; ELISA, Enzyme-linked immunosorbent assay; IGF, Insulin-like growth factors; IGFBP, Insulin-like growth factor binding protein; MD, Mean difference; PEDro, Physiotherapy evidence database; RCT, Randomized controlled trials; SD, Standard deviation. Background: Insulin-like growth factors (IGF´s) play a crucial role in controlling cancer cell proliferation, differentiation and apoptosis. Exercise has been postulated as an effective intervention in improving cancerrelated outcomes and survival, although its effects on IGF´s are not well understood. This meta-analysis aimed to determine the effects of exercise in modulating IGF´s system in breast cancer survivors. Methods: Databases of PuMed, EMBASE, Cochrane Central Register of Controlled Trials, EMBASE, ClinicalTrials. gov, SPORTDiscus, LILACS and Scopus were systematically searched up to November 2014. Effect estimates were calculated through a random-effects model of meta-analysis according to the DerSimonian and Laird method. Heterogeneity was evaluated with the I2 test. Risk of bias and methodological quality were evaluated using the PEDro score. Results: Five randomized controlled trials (n = 235) were included. Most women were post-menopausal. Highquality and low risk of bias were found (mean PEDro score = 6.2 ± 1). Exercise resulted in significant improvements on IGF-I, IGF-II, IGFBP-I, IGFBP-3, Insulin and Insulin resistance (P < 0.05). Non-significant differences were found for Glucose. Aerobic exercise improved IGF-I, IGFBP-3 and Insulin. No evidence of publication bias was detected by Egger´s test (p = 0.12). Conclusions: Exercise improved IGF´s in breast cancer survivors. These findings provide novel insight regarding the molecular effects of exercise on tumoral microenvironment, apoptosis and survival in breast cancer survivors. 2018-03-09T08:52:27Z 2018-03-09T08:52:27Z 2016 info:eu-repo/semantics/article Meneses-Echávez, J. F.; et al. The insulin-like growth factor system is modulated by exercise in breast cancer survivors: a systematic review and meta-analysis. BMC Cancer, 16: 682 (2016). [http://hdl.handle.net/10481/49911] 1471-2407 http://hdl.handle.net/10481/49911 10.1186/s12885-016-2733-z eng http://creativecommons.org/licenses/by-nc-nd/3.0/ info:eu-repo/semantics/openAccess Creative Commons Attribution-NonCommercial-NoDerivs 3.0 License Biomed Central