Next Article in Journal
Application of Convolutional Neural Networks for Diagnosis of Eosinophilic Esophagitis Based on Endoscopic Imaging
Previous Article in Journal
Eye Involvement in Wilson’s Disease: A Review of the Literature
 
 
Font Type:
Arial Georgia Verdana
Font Size:
Aa Aa Aa
Line Spacing:
Column Width:
Background:
Systematic Review

Association between Physical Activity and Telomere Length in Women with Breast Cancer: A Systematic Review

1
Department of Convergence Medicine, Wonju College of Medicine, Yonsei University, Wonju 26426, Korea
2
Yonsei Institute of Sports Science and Exercise Medicine (YISSEM), Wonju 26426, Korea
3
Department of Physiology, College of Medicine, Korea University, Seoul 02841, Korea
*
Author to whom correspondence should be addressed.
These authors contributed equally to this work.
J. Clin. Med. 2022, 11(9), 2527; https://doi.org/10.3390/jcm11092527
Submission received: 2 March 2022 / Revised: 16 April 2022 / Accepted: 28 April 2022 / Published: 30 April 2022
(This article belongs to the Section Epidemiology & Public Health)

Abstract

:
The association between physical activity and telomere length (TL) has been continuously reported. However, the interplay of physical activity and TL among women with breast cancer has not been elucidated. Thus, the purpose of this systematic review was to synthesize the evidence for the association of physical activity with TL in women with breast cancer. Systematic searches were conducted to identify quantified studies using MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, Web of Science, and Clinical Trials.gov. Five studies were included in this systematic review. Three of the five studies reported that physical activity has a significant relationship in delaying TL shortening, but others observed no association between physical activity and TL in breast cancer survivors. Although the heterogeneous studies acted as limitations in drawing clear conclusions, physical activity strategies show encouraging impacts in delaying TL shortening. To understand the effects of physical activity on TL shortening in breast cancer survivors, further studies are needed considering the tissue site, treatments for breast cancer, DNA extraction methods, and tools for measuring physical activity.

1. Introduction

Telomeres are nucleoprotein structures located at the end of human eukaryotic chromosomes, and they protect against genome instability and damage [1]. Telomeres shorten with each cell cycle in most cells; thus, telomere length (TL) represents the proliferative history of the cell [2,3]. Once telomeres approach a critical size, cell-signaling events occur and induce cellular senescence or apoptosis [4].
TL is negatively associated with biological aging and age-related diseases such as diabetes [5], dementia [6], cancer [7,8], and chronic psychiatric disorders [9,10]. In particular, there is growing evidence of the association between breast cancer and telomere length. Previous studies reported that an increase in inflammatory markers [11], an increased mitochondrial dysfunction [12], and the accumulation [13] of reactive oxygen species not only increase the risk of breast cancer but have a close relationship with telomere shortening. Furthermore, it has been shown that telomere shortening is related to the mutation of the breast cancer susceptibility gene 2 (BRCA2), which is highly associated with the recurrence of breast cancer [14]. A recent review reported that TL could be a valuable prognostic marker of breast cancer despite major methodological differences in measuring TL [15].
Physical activity and exercise are important modifiable factors in breast cancer prevention [16], prognosis [17,18], and mortality [19]. They also have a strong association with delayed telomere shortening. A meta-analysis revealed that active individuals had significantly longer telomeres compared to inactive individuals regardless of the intensity of exercise (mean difference 0.15, 95% CI 0.05–0.24, I2 = 99%) [20]. However, studies on the effect of physical activity or exercise on TL in breast cancer survivors are limited, and inconsistent results have been obtained [21,22,23,24,25].
Therefore, we aimed to comprehensively analyze the association and effect of physical activity or exercise on delaying telomere shortening in women with breast cancer.

2. Materials and Methods

2.1. Search Strategy

The current study protocol was registered in the PROSPERO database (No. CRD42021253013), and the study was conducted according to the Preferred Reporting Items for Systematic Review and Meta-analyses (PRISMA) checklist [26]. We searched the following databases: MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library), Web of Science, and http://ClinicalTrials.gov (accessed on 23 April 2021) from inception up to April 2021. We also reviewed the reference lists of recent systematic reviews.
All articles that assessed the relationship between physical activity and TL or the effects of exercise on TL in breast cancer survivors were included in this review. The search was performed using the following terms: “breast cancer” AND “physical activity” OR “exercise” AND “telomere length”. The full search strategy is available in the Table S1.
This section may be divided by subheadings. It should provide a concise and precise description of the experimental results, their interpretation, as well as the experimental conclusions that can be drawn.

2.2. Eligibility Criteria

We included studies that (1) were quantitative studies, including cross-sectional, case-control, and intervention studies, and (2) reported TL as mean ± standard deviation or median (interquartile range) or TL/single-copy gene (T/S) ratio.

2.3. Data Extraction and Quality Assessment

Two reviewers (J.M. and J.K.) independently screened all titles, abstracts, and full texts to identify studies based on the inclusion criteria using the Covidence systematic review software (Veritas Health Innovation, Melbourne, Australia, www.covidence.org accessed from 25 April 2021 to 7 May 2021). Any disagreement between the reviewers was resolved through discussion. The information obtained from each selected study included the first author’s name, year of publication, study design, population, patients’ ages, method of TL evaluation, tissue where TL measurement was conducted, tool for assessing physical activity, intervention (i.e., type of exercise, frequency, intensity, time), main results, and any other information considered relevant.
The quality of eligible studies was assessed with the Newcastle-Ottawa Scale (NOS). Considering the different study designs, we used three versions of the NOS for randomized controlled trials, cross-sectional studies, and case-control studies, respectively [27]. NOS scales for non-randomized studies and randomized controlled trials consist of three domains: selection, comparability, and outcome/exposure. We defined NOS ≥ 7 as high quality and 4 < NOS < 7 as low to moderate quality.

3. Results

3.1. Study Search and Selection

A total of 331 studies were retrieved using the search strategy (Table S1), of which 293 were retained after the title and abstract were screened and duplicates were removed. Of these 293 studies, 269 were excluded because they were considered non-relevant. After a full-text review of the 24 papers considered relevant, 19 studies were excluded (2 with duplicate data, 4 without TL results, 3 conference abstracts, and 8 protocol, editorial papers, and review papers). Finally, 5 studies (2099 participants) were included in this review (Figure 1).

3.2. Description of the Studies and Quality Assessment

Table 1 shows the summary of the included studies and the results of the quality assessment. Of the five studies, two were randomized controlled trials, two were cross-sectional studies, and one was a case-control study. For the TL assessment, three studies used quantitative-polymerase chain reaction, one used a fluorescence in situ hybridization assay, and one used the terminal restriction fragment method. The mean NOS score was 6.2 (range: 5–7), and all included studies had moderate to high scores (Table 1).

3.3. Effects of Exercise on Telomere Length in Women with Breast Cancer

Of the two randomized controlled trial studies, one reported that exercise intervention had a significant effect on delaying TL shortening, while the other reported no intervention effect on TL (Table 2).
Santa-Maria et al. [21] conducted a 12-month web-based exercise intervention on 96 obese breast cancer survivors treated in their region. The intervention group received a total of 21 phone consultations consisting of 20 min weight-loss counseling once a week for the first 3 months and once a month for the remaining 9 months. Professional exercise coaches monitored the exercise log, meal log, and weight on the web-based platform. The control group was advised by medical staff to maintain a healthy weight and was provided with weight loss consultations from exercise professionals once. After a 6-month intensive lifestyle intervention, TL in the intervention group reduced by 3% while TL in the usual care group reduced by 5% (p > 0.05). In addition, when classifying by stage of breast cancer, stage 0 or 1 showed a significantly lower reduction in TL for the intervention group than for the control group after 6 months (p < 0.05). However, there were no significant differences between the groups for breast cancer survivors who were diagnosed with cancer exceeding stage 2.
Sanft et al. [24] conducted an exercise intervention on 151 obese breast cancer survivors who had been involved in dietary regulation and exercise to achieve weight loss over 6 months. The weight loss strategy included attaining 150 min/week of moderate-intensity activity and 10,000 steps per day as well as reducing calories to 1200–2000 kcal/day. In addition, the patients were advised to reduce dietary fat to <25% of the total energy intake and participate in behavior modification sessions once or twice every month. No significant difference was noted in the change in TL between the intervention and control groups. In addition, the TL was not significantly associated with weight loss or chemotherapy.

3.4. Association between Physical Activity and Telomere Length in Women with Breast Cancer

Three cross-sectional or case-control studies were conducted to analyze the associations between physical activity or exercise and TL among breast cancer patients or survivors (Table 3). Two studies showed a significant quantitative correlation between physical activity and TL in breast cancer patients, while one reported that no association existed between exercise and TL. A study of 162 breast cancer patients, who were scheduled to undergo surgery, identified linear trends in the positive association between total physical activity and TL (p < 0.05). Moreover, linear trends for increasing TL were observed for physical activity at the transportation-related physical activity (p < 0.05). However, age, stage of cancer, and menopausal status were not significantly associated with TL [27]. Garland et al. [22] used the International Physical Activity Questionnaire (IPAQ) to analyze the association between physical activity and TL among 392 postmenopausal breast cancer survivors. Compared to those who participated in any physical activity, breast cancer survivors who participated in moderate to vigorous physical activity had significantly longer TL (p < 0.05). However, a case-control study by Qu et al. [25] announced no significant association between TL and exercise.

4. Discussion

This systematic review was conducted to clarify the association between physical activity and TL in breast cancer patients and survivors. Five papers were reviewed and there was difficulty in synthesizing the research results because of heterogeneity between the studies.
Previous studies reported that physical activity may compensate for shortened TL in cancer survivors [24,28,29,30]. Physical activity may alleviate the decrease in TRF-2 [31]. Furthermore, exercise can help reduce oxidative stress [32] and inflammatory responses [21] which contribute to telomere damage. The stress response can damage cells, releasing damaged cell components, while exercise promotes autophagy [33]. Increased physical activity has been reported to reduce factors related to oxidative stress and inflammation, such as high-sensitivity C-reactive protein, insulin resistance, interleukin-6, tumor necrosis factor-alpha, granulocyte colony-stimulating factor, and F2-isoprostane [11,34,35].
Although we examined the correlation between physical activity and TL of breast cancer patients and survivors, it was challenging to derive consistent results owing to interstudy heterogeneity.
There are three prominent reasons for why the results differed among the studies.
First, the effect of the mediator variables on the length of the telomeres should be considered. Factors such as ethnicity [36], cancer stage distribution [37], radiation therapy [38], chemotherapy [39], and menopause [40] affect breast cancer prognosis and treatment and are also related to TL. In addition, breast cancer survivors experience a mix of both cancer- and metabolic- related problems. Heo, J et al. [41] reported that 36.7% of breast cancer survivors had been newly diagnosed with comorbidities such as diabetes, hypertension, and metabolic syndrome.
Second, we could consider the difference in intervention effectiveness across studies. In our extracted intervention studies, the participants of both studies [21,24] experienced significant weight loss. While 20% of the participants showed a reduction in their body fat by more than 5% in the study by Sanft et al. [24], change in body composition was not reported in the study by Santa-Maria et al. [21]. If the participants’ weight loss in the Santa-Maria et al. [21] was derived from muscle reduction, the effect could be considered relatively weak. As breast cancer prognosis is highly related to body fat and muscle, it is necessary to carefully monitor body composition rather than simply focus on weight loss.
Third, there were differences in the evaluation of TL and physical activity due to a variety of measurement tools. Diverse methods were used for the TL analysis in our extracted studies, and the specimen types employed were also different. Generally, TL could differ depending on the tissue [42] and the analysis approach [43]. In this review, three out of five studies used the qPCR method for the evaluation of TL. qPCR has advantages because (1) TL can be measured even in small amounts of DNA and (2) the process is less labor-intensive. However, it has a limitation, since (1) there are variations between and within “batches” and (2) there is a lack of reference standards. The TRF method is the golden standard, but it has the cons of intensive labor and requires a large amount of DNA [44]. In addition, the whole blood and PBMCs have good DNA yield and quality, while salivary samples could destabilize DNA yields depending on temperature [45]. In the cross-sectional studies, the heterogeneity of the research results arose from the difference in the physical activity measurement tools that were used. The two cross-sectional studies analyzed the amount of physical activity using the Past Year Total Physical Activity Questionnaire (PYTPAQ) and the IPAQ short form, respectively. Since the amount of physical activity was measured using the questionnaires, the results may have been subject to self-reporting bias. Indeed, the contents of the questionnaires such as “physical activity domain” or “intensity”, and the recall period such as “during the past year” or “during the last 7 days”, could affect the amount of physical activity declared. Lee et al. [43] showed that questionnaires tend to overestimate the amount of physical activity performed by subjects compared to when an accelerometer is used. Therefore, more studies need to analyze the association between the intensity of physical activity and TL with an accelerometer.
The current study has several limitations. First, there is heterogeneity among the extracted studies. There are differences in the specimen, characteristics of participants, and variability of measurement tools in each study. Secondly, we should be cautious of generalizing the results, given that the included studies were exclusively published in English. Third, the method used to search the literature and retrieve from published articles may have caused reporting bias.
Despite the limitations, it is meaningful in that it confirmed the tendency of the association between physical activity or exercise and the TL of breast cancer survivors. Future studies need to clarify the effects of various confounding variables such as extracted tissues, characteristics of the participants, treatment modalities for breast cancer, and physical activity measurement tools. In addition, rigorous efforts are required to address existing challenges associated with TL sample storage and processing in all tissue types to ensure reproducibility and reliability of telomere samples and analytical methods.

Supplementary Materials

The following supporting information can be downloaded at: https://www.mdpi.com/article/10.3390/jcm11092527/s1, Table S1: Search strategy.

Author Contributions

Conceptualization, J.M. and J.Y.K.; methodology, J.M., J.Y.C. and I.D.K.; writing—original draft preparation, J.M.; writing—review and editing, J.M., J.Y.C. and I.D.K., visualization, J.M.; supervision, I.D.K.; funding acquisition, I.D.K. All authors have read and agreed to the published version of the manuscript.

Funding

This research was supported by the National Research Foundation of Korea (NRF) grant funded by the Korean government [No. NRF-2020R1I1A3070520].

Data Availability Statement

Not applicable.

Acknowledgments

The authors would like to thank Myung Ha Kim (librarian) for help with the systematic review search.

Conflicts of Interest

The authors declare no conflict of interest.

References

  1. Blackburn, E.H.; Epel, E.S.; Lin, J. Human telomere biology: A contributory and interactive factor in aging, disease risks, and protection. Science 2015, 350, 1193–1198. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  2. Calado, R.T.; Young, N.S. Telomere diseases. N. Engl. J. Med. 2009, 361, 2353–2365. [Google Scholar] [CrossRef] [PubMed]
  3. Turner, K.J.; Vasu, V.; Griffin, D.K. Telomere Biology and Human Phenotype. Cells 2019, 8, 73. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  4. Zakian, V.A. Telomeres: The beginnings and ends of eukaryotic chromosomes. Exp. Cell Res. 2012, 318, 1456–1460. [Google Scholar] [CrossRef] [Green Version]
  5. Cheng, F.; Carroll, L.; Joglekar, M.V.; Januszewski, A.S.; Wong, K.K.; Hardikar, A.A.; Jenkins, A.J.; Ma, R.C.W. Diabetes, metabolic disease, and telomere length. Lancet Diabetes Endocrinol. 2021, 9, 117–126. [Google Scholar] [CrossRef]
  6. Liu, Y.; Ma, C.; Li, P.; Ma, C.; He, S.; Ping, F.; Zhang, H.; Li, W.; Xu, L.; Li, Y. Leukocyte Telomere Length Independently Predicts 3-Year Diabetes Risk in a Longitudinal Study of Chinese Population. Oxid. Med. Cell Longev. 2020, 2020, 9256107. [Google Scholar] [CrossRef]
  7. Ma, H.; Zhou, Z.; Wei, S.; Liu, Z.; Pooley, K.A.; Dunning, A.M.; Svenson, U.; Roos, G.; Hosgood, H.D., 3rd; Shen, M.; et al. Shortened telomere length is associated with increased risk of cancer: A meta-analysis. PLoS ONE 2011, 6, e20466. [Google Scholar] [CrossRef]
  8. Zhang, C.; Chen, X.; Li, L.; Zhou, Y.; Wang, C.; Hou, S. The Association between Telomere Length and Cancer Prognosis: Evidence from a Meta-Analysis. PLoS ONE 2015, 10, e0133174. [Google Scholar] [CrossRef]
  9. Guo, Y.; Yu, H. Leukocyte Telomere Length Shortening and Alzheimer’s Disease Etiology. J. Alzheimer’s Dis. 2019, 69, 881–885. [Google Scholar] [CrossRef]
  10. Lin, P.Y.; Huang, Y.C.; Hung, C.F. Shortened telomere length in patients with depression: A meta-analytic study. J. Psychiatr. Res. 2016, 76, 84–93. [Google Scholar] [CrossRef]
  11. O’Donovan, A.; Pantell, M.S.; Puterman, E.; Dhabhar, F.S.; Blackburn, E.H.; Yaffe, K.; Cawthon, R.M.; Opresko, P.L.; Hsueh, W.C.; Satterfield, S.; et al. Cumulative inflammatory load is associated with short leukocyte telomere length in the Health, Aging and Body Composition Study. PLoS ONE 2011, 6, e19687. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  12. Zhu, Y.; Liu, X.; Ding, X.; Wang, F.; Geng, X. Telomere and its role in the aging pathways: Telomere shortening, cell senescence and mitochondria dysfunction. Biogerontology 2019, 20, 1–16. [Google Scholar] [CrossRef] [PubMed]
  13. Chakravarti, D.; LaBella, K.A.; DePinho, R.A. Telomeres: History, health, and hallmarks of aging. Cell 2021, 184, 306–322. [Google Scholar] [CrossRef] [PubMed]
  14. Thorvaldsdottir, B.; Aradottir, M.; Stefansson, O.A.; Bodvarsdottir, S.K.; Eyfjord, J.E. Telomere Length Is Predictive of Breast Cancer Risk in BRCA2 Mutation Carriers. Cancer Epidemiol. Biomark. Prev. 2017, 26, 1248–1254. [Google Scholar] [CrossRef] [Green Version]
  15. Ennour-Idrissi, K.; Maunsell, E.; Diorio, C. Telomere Length and Breast Cancer Prognosis: A Systematic Review. Cancer Epidemiol. Biomark. Prev. 2017, 26, 3–10. [Google Scholar] [CrossRef] [Green Version]
  16. Chen, X.; Wang, Q.; Zhang, Y.; Xie, Q.; Tan, X. Physical Activity and Risk of Breast Cancer: A Meta-Analysis of 38 Cohort Studies in 45 Study Reports. Value Health 2019, 22, 104–128. [Google Scholar] [CrossRef] [Green Version]
  17. Peterson, L.L.; Ligibel, J.A. Physical Activity and Breast Cancer: An Opportunity to Improve Outcomes. Curr. Oncol. Rep. 2018, 20, 50. [Google Scholar] [CrossRef]
  18. Patterson, R.E.; Cadmus, L.A.; Emond, J.A.; Pierce, J.P. Physical activity, diet, adiposity and female breast cancer prognosis: A review of the epidemiologic literature. Maturitas 2010, 66, 5–15. [Google Scholar] [CrossRef]
  19. Nascimento, W.; Ferrari, G.; Martins, C.B.; Rey-Lopez, J.P.; Izquierdo, M.; Lee, D.H.; Giovannucci, E.L.; Rezende, L.F.M. Muscle-strengthening activities and cancer incidence and mortality: A systematic review and meta-analysis of observational studies. Int. J. Behav. Nutr. Phys. Act. 2021, 18, 69. [Google Scholar] [CrossRef]
  20. Lin, X.; Zhou, J.; Dong, B. Effect of different levels of exercise on telomere length: A systematic review and meta-analysis. J. Rehabil. Med. 2019, 51, 473–478. [Google Scholar] [CrossRef] [Green Version]
  21. Santa-Maria, C.A.; Coughlin, J.W.; Sharma, D.; Armanios, M.; Blackford, A.L.; Schreyer, C.; Dalcin, A.; Carpenter, A.; Jerome, G.J.; Armstrong, D.K.; et al. The Effects of a Remote-based Weight Loss Program on Adipocytokines, Metabolic Markers, and Telomere Length in Breast Cancer Survivors: The POWER-Remote Trial. Clin. Cancer Res. 2020, 26, 3024–3034. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  22. Garland, S.N.; Johnson, B.; Palmer, C.; Speck, R.M.; Donelson, M.; Xie, S.X.; DeMichele, A.; Mao, J.J. Physical activity and telomere length in early stage breast cancer survivors. Breast Cancer Res. 2014, 16, 413. [Google Scholar] [CrossRef] [PubMed]
  23. Hagstrom, A.D.; Denham, J. The effect of resistance training on telomere length in women recovering from breast cancer. J. Funct. Morphol. Kinesiol. 2018, 3, 9. [Google Scholar] [CrossRef] [Green Version]
  24. Sanft, T.; Usiskin, I.; Harrigan, M.; Cartmel, B.; Lu, L.; Li, F.Y.; Zhou, Y.; Chagpar, A.; Ferrucci, L.M.; Pusztai, L.; et al. Randomized controlled trial of weight loss versus usual care on telomere length in women with breast cancer: The lifestyle, exercise, and nutrition (LEAN) study. Breast Cancer Res. Treat. 2018, 172, 105–112. [Google Scholar] [CrossRef]
  25. Qu, S.; Wen, W.; Shu, X.O.; Chow, W.H.; Xiang, Y.B.; Wu, J.; Ji, B.T.; Rothman, N.; Yang, G.; Cai, Q.; et al. Association of leukocyte telomere length with breast cancer risk: Nested case-control findings from the Shanghai Women’s Health Study. Am. J. Epidemiol. 2013, 177, 617–624. [Google Scholar] [CrossRef] [Green Version]
  26. Moher, D.; Shamseer, L.; Clarke, M.; Ghersi, D.; Liberati, A.; Petticrew, M.; Shekelle, P.; Stewart, L.A.; Group, P.-P. Preferred reporting items for systematic review and meta-analysis protocols (PRISMA-P) 2015 statement. Syst. Rev. 2015, 4, 1. [Google Scholar] [CrossRef] [Green Version]
  27. Ennour-Idrissi, K.; Tetu, B.; Maunsell, E.; Poirier, B.; Montoni, A.; Rochette, P.J.; Diorio, C. Association of Telomere Length with Breast Cancer Prognostic Factors. PLoS ONE 2016, 11, e0161903. [Google Scholar] [CrossRef] [Green Version]
  28. Wang, Z.; Zhang, Z.; Guo, Y.; Shui, H.; Liu, G.; Jin, T.; Wang, H. Shorter Telomere Length Is Associated with Increased Breast Cancer Risk in a Chinese Han Population: A Case-Control Analysis. J. Breast Cancer 2018, 21, 391–398. [Google Scholar] [CrossRef]
  29. Dickinson, S.L.; Golzarri-Arroyo, L.; Brown, A.W.; McComb, B.; Kahathuduwa, C.N.; Allison, D.B. Change in study randomization allocation needs to be included in statistical analysis: Comment on ‘Randomized controlled trial of weight loss versus usual care on telomere length in women with breast cancer: The lifestyle, exercise, and nutrition (LEAN) study’. Breast Cancer Res. Treat. 2019, 175, 263–264. [Google Scholar] [CrossRef]
  30. Nomikos, N.N.; Nikolaidis, P.T.; Sousa, C.V.; Papalois, A.E.; Rosemann, T.; Knechtle, B. Exercise, Telomeres, and Cancer: “The Exercise-Telomere Hypothesis”. Front. Physiol. 2018, 9, 1798. [Google Scholar] [CrossRef] [Green Version]
  31. Khan, S.; Chuturgoon, A.A.; Naidoo, D.P. Telomeres and atherosclerosis. Cardiovasc. J. Afr. 2012, 23, 563–571. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  32. Friedenreich, C.M.; Pialoux, V.; Wang, Q.; Shaw, E.; Brenner, D.R.; Waltz, X.; Conroy, S.M.; Johnson, R.; Woolcott, C.G.; Poulin, M.J.; et al. Effects of exercise on markers of oxidative stress: An Ancillary analysis of the Alberta Physical Activity and Breast Cancer Prevention Trial. BMJ Open Sport Exerc. Med. 2016, 2, e000171. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  33. Dethlefsen, M.M.; Halling, J.F.; Moller, H.D.; Plomgaard, P.; Regenberg, B.; Ringholm, S.; Pilegaard, H. Regulation of apoptosis and autophagy in mouse and human skeletal muscle with aging and lifelong exercise training. Exp. Gerontol. 2018, 111, 141–153. [Google Scholar] [CrossRef] [PubMed]
  34. Campbell, P.T.; Gross, M.D.; Potter, J.D.; Schmitz, K.H.; Duggan, C.; McTiernan, A.; Ulrich, C.M. Effect of exercise on oxidative stress: A 12-month randomized, controlled trial. Med. Sci. Sports Exerc. 2010, 42, 1448–1453. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  35. Zhao, J.; Miao, K.; Wang, H.; Ding, H.; Wang, D.W. Association between telomere length and type 2 diabetes mellitus: A meta-analysis. PLoS ONE 2013, 8, e79993. [Google Scholar] [CrossRef]
  36. Brown, L.; Needham, B.; Ailshire, J. Telomere Length Among Older U.S. Adults: Differences by Race/Ethnicity, Gender, and Age. J. Aging Health 2017, 29, 1350–1366. [Google Scholar] [CrossRef]
  37. Fordyce, C.A.; Heaphy, C.M.; Bisoffi, M.; Wyaco, J.L.; Joste, N.E.; Mangalik, A.; Baumgartner, K.B.; Baumgartner, R.N.; Hunt, W.C.; Griffith, J.K. Telomere content correlates with stage and prognosis in breast cancer. Breast Cancer Res. Treat. 2006, 99, 193–202. [Google Scholar] [CrossRef]
  38. Gallicchio, L.; Gadalla, S.M.; Murphy, J.D.; Simonds, N.I. The Effect of Cancer Treatments on Telomere Length: A Systematic Review of the Literature. J. Natl. Cancer Inst. 2018, 110, 1048–1058. [Google Scholar] [CrossRef]
  39. Dalgard, C.; Benetos, A.; Verhulst, S.; Labat, C.; Kark, J.D.; Christensen, K.; Kimura, M.; Kyvik, K.O.; Aviv, A. Leukocyte telomere length dynamics in women and men: Menopause vs. age effects. Int. J. Epidemiol. 2015, 44, 1688–1695. [Google Scholar] [CrossRef] [Green Version]
  40. Friedrich, U.; Griese, E.; Schwab, M.; Fritz, P.; Thon, K.; Klotz, U. Telomere length in different tissues of elderly patients. Mech. Ageing Dev. 2000, 119, 89–99. [Google Scholar] [CrossRef]
  41. Heo, J.; Chun, M.; Oh, Y.T.; Noh, O.K.; Kim, L. Metabolic comorbidities and medical institution utilization among breast cancer survivors: A national population-based study. Korean J. Intern. Med. 2020, 35, 421–428. [Google Scholar] [CrossRef] [PubMed]
  42. Lai, T.P.; Wright, W.E.; Shay, J.W. Comparison of telomere length measurement methods. Philos. Trans. R Soc. Lond. B Biol. Sci. 2018, 373, 20160451. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  43. Lee, P.H.; Macfarlane, D.J.; Lam, T.H.; Stewart, S.M. Validity of the International Physical Activity Questionnaire Short Form (IPAQ-SF): A systematic review. Int. J. Behav. Nutr. Phys. Act. 2011, 8, 115. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  44. Montpetit, A.J.; Alhareeri, A.A.; Montpetit, M.; Starkweather, A.R.; Elmore, L.W.; Filler, K.; Mohanraj, L.; Burton, C.W.; Menzies, V.S.; Lyon, D.E.; et al. Telomere length: A review of methods for measurement. Nurs. Res. 2014, 63, 289–299. [Google Scholar] [CrossRef] [Green Version]
  45. Lin, J.; Smith, D.L.; Esteves, K.; Drury, S. Telomere length measurement by qPCR—Summary of critical factors and recommendations for assay design. Psychoneuroendocrino 2019, 99, 271–278. [Google Scholar] [CrossRef]
Figure 1. PRISMA flow diagram for systematic review.
Figure 1. PRISMA flow diagram for systematic review.
Jcm 11 02527 g001
Table 1. Characteristics and quality assessment of included studies.
Table 1. Characteristics and quality assessment of included studies.
Author (Year)CountryStudy DesignNumber of SubjectSpecimen TypeMethod of Evaluation
of Telomere
Quality Assessment
Santa-Maria, C. A. et al. (2020) [21]USARandomized controlled trial (RCT) 96 breast cancer survivorsLymphocytes and granulocytesFluorescence in situ hybridization (FISH) assay5
Sanft, T. et al. (2018) [24]USARandomized controlled trial (RCT) 151 breast cancer survivors Peripheral blood samplesQuantitative-polymerase chain reaction (qPCR), T/S6
Ennour-Idrissi, K., et al. (2016) [27]CanadaCross-sectional study164 women who underwent surgery for unilateral breast cancerPeripheral white blood cellsQuantitative-polymerase chain reaction (qPCR), T/S 7
Garland, S. N. et al. (2014) [22]USACross-sectional study392 postmenopausal women with stage I–III breast cancerPeripheral blood mononuclear cells (PBMCs)Terminal restriction fragment (TRF) 7
Qu, S. et al. (2013) [25]ChinaCase-control study1296 (601 incident breast cancer cases, 605 control)Peripheral blood samplesMonochrome multiplex quantitative polymerase chain reaction (qPCR), T/S6
PBMCs—peripheral blood mononuclear cell, qPCR—real-time quantitative PCR detecting system, TRF—terminal restriction fragment, T/S ratio—telomere (T), single copy gene (S) ratio T/S. Quality assessments were conducted using Newcastle-Ottawa Scale (NOS).
Table 2. The summary of the included randomized controlled trials studies.
Table 2. The summary of the included randomized controlled trials studies.
Author (Year)SubjectAgePurpose of InterventionContents of InterventionDurationResult
Santa-Maria, C. A. et al. (2020) [21]96 obese a
breast cancer survivors with stage I–III breast cancer
Median (range)
intervention
53 (33–71)
self-directed 55 (30–73)
Weight lossPOWER-Remote
-
Frequency: weekly for 3 months, monthly for additional 9 months
-
Intensity: unknown
-
Type: telephone and web-based platform
-
Time: unknown
12-month
-
NS.
Change TL: 0.1 ± 0.7 in POWER-remote group, 0.1 ± 0.7 in self-directed group (p = 0.76)
Sanft, T. et al. (2018) [24]151 obese a breast cancer survivorsMean ± SD
57.8 ± 7.7
Weight lossWeight loss intervention group (WL)
ㆍDiet: reducing calorie intake
ㆍPhysical activity
-
Frequency: individualized counseling sessions weekly
-
Intensity: moderate intensity
-
Type: combined
-
Time: 30 min
6-month
-
TL shortening in total: NS.
Change TL: −3% in WL vs. −5% in control (p = 0.12).
-
TL shortening in stage 0/1: WL < Control
Change TL: −7% in WL vs. −8% in control (p = 0.01).
a Body mass index ≥ 25 kg/m2, abbreviations: NS—non-significant, TL—telomere length.
Table 3. The summary of the included non-randomized controlled trials studies.
Table 3. The summary of the included non-randomized controlled trials studies.
Author (Year)Study DesignSubjectAgePA Measurement ToolResult
Ennour-Idrissi, K., et al. (2016) [27]Cross-sectional study162 women who underwent surgery for unilateral breast cancerMean ± SD
52.6 ± 7.9
-
Past Year Total Physical Activity Questionnaire
-
PA↑ = TL
TPA (rs = 0.17, p = 0.033), occupational PA (rs = 0.15, p = 0.054) and transportation-related PA (rs = 0.19, p = 0.019).
Garland, S. N. et al. (2014) [22]Cross-sectional study392 postmenopausal women with stage I–III breast cancerMean ± SD
61.97 ± 10.36
-
Physical activity: International Physical Activity Questionnaire (IPAQ)
-
TL shortening: No PA > MVPA
(mean 5.84 kb versus 6.11 kb; p = 0.006).
-
PA↓ = TL
(Adjusted coefficient (Adj β) = −0.22; 95% CI, −0.41 to −0.03; p = 0.03)
Qu, S. et al. (2013) [25]Case-control study601 incident breast cancer cases 695 matched as controlsMean ± SD
52.7 ± 8.8 in case
53.4 ± 9.0 in control
-
Unknown
-
NS.
(exercise and telomere length p for interaction = 0.612)
Abbreviations: SD—standard deviation, NS—non-significant, TL—telomere length, PA—physical activity, TPA—total physical activity, MVPA—moderate to vigorous physical activity, CI—confidence interval, PA↑—high levels of physical activity, PA↓—low level of physical acitivity, TL↑—long TL, TL↓—short TL.
Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Share and Cite

MDPI and ACS Style

Min, J.; Kim, J.Y.; Choi, J.Y.; Kong, I.D. Association between Physical Activity and Telomere Length in Women with Breast Cancer: A Systematic Review. J. Clin. Med. 2022, 11, 2527. https://doi.org/10.3390/jcm11092527

AMA Style

Min J, Kim JY, Choi JY, Kong ID. Association between Physical Activity and Telomere Length in Women with Breast Cancer: A Systematic Review. Journal of Clinical Medicine. 2022; 11(9):2527. https://doi.org/10.3390/jcm11092527

Chicago/Turabian Style

Min, Jihee, Ji Young Kim, Ji Yeong Choi, and In Deok Kong. 2022. "Association between Physical Activity and Telomere Length in Women with Breast Cancer: A Systematic Review" Journal of Clinical Medicine 11, no. 9: 2527. https://doi.org/10.3390/jcm11092527

Note that from the first issue of 2016, this journal uses article numbers instead of page numbers. See further details here.

Article Metrics

Back to TopTop