Short-term moderate exercise programs reduce oxidative DNA damage as determined by high-performance liquid chromatography-electrospray ionization-mass spectrometry in patients with colorectal carcinoma following primary treatment.
OBJECTIVE
Oxidative DNA damage is believed to be involved in tumor formation and may be an important biomarker for malignant transition or relapse. A decrease of such damage has been observed in human and animal studies following dietary intervention and/or changes in lifestyle such as physical exercise at different levels of intensity. The purpose of this study was to carry out a clinical trial comparing the effects of a short-term (2 weeks) exercise program of moderate intensity (0.3-0.4 x maximal exercise capacity) (MI) versus high intensity (0.5-0.6 x maximal exercise capacity) (HI) on individual urinary excretion of 8-oxo-dG before and after completion of the exercise programs.


METHODS
In this short-term, prospective and randomized trial, 19 patients with colorectal cancer were allocated to the MI group following primary therapy and 29 to the HI group. Urinary 8-oxo-dG excretion concentration was determined by a highly sensitive detection method using high-performance liquid chromatography coupled to electrospray ionization mass spectrometry (HPLC-ESI-MS). Concentrations were determined immediately before and after completion of the exercise programs.


RESULTS
Using HPLC-ESI-MS, it was shown that MI exercise significantly reduced urinary 8-oxo-dG excretion levels from 8.47 +/- 1.99 to 5.81 +/- 1.45 (ng/mg creatinine, mean +/- SE, p = 0.02), whereas HI exercise resulted in a non-significant increase from 5.00 +/- 1.31 to 7.11 +/- 1.63 (ng/mg creatinine, p = 0.18). Clinical characteristics (gender, age, body mass index (BMI), diet, chemotherapy/irradiation) were not associated/correlated with urinary 8-oxo-dG levels.


CONCLUSIONS
By using HPLC-ESI-MS it was shown that short-term MI exercise after primary therapy in patients with colorectal cancer was associated with lower levels of urinary 8-oxo-dG, suggesting decreased oxidative DNA damage. In contrast, HI exercise tended to increase DNA damage. A prospective trial is now warranted to prove that reduced oxidative DNA damage lowers the risk of relapse of colorectal cancer in treated patients.
Allgayer
Hubert
H
Oncology Department, Reha-klinik Ob der Tauber, Academic Teaching Hospital, University of Heidelberg, Bad Mergentheim, Germany. allgayer@reha-klinik-odt.de
Owen
Robert W
RW
Nair
Jagadeesan
J
Spiegelhalder
Bertold
B
Streit
Jürgen
J
Reichel
Christoph
C
Bartsch
Helmut
H
D000080242:8-Hydroxy-2'-Deoxyguanosine; D014408:Biomarkers, Tumor / Q000652:urine; D002277:Carcinoma / Q000235:genetics / Q000628:therapy* / Q000652:urine; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D015179:Colorectal Neoplasms / Q000235:genetics / Q000628:therapy* / Q000652:urine; D003131:Combined Modality Therapy / Q000379:methods; D004249:DNA Damage / Q000235:genetics*; D003849:Deoxyguanosine / Q000031:analogs & derivatives* / Q000652:urine; D005081:Exercise Therapy / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D018384:Oxidative Stress / Q000235:genetics*; D011446:Prospective Studies; D015203:Reproducibility of Results; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods; D013997:Time Factors; D016896:Treatment Outcome
D014408:Biomarkers, Tumor; D000080242:8-Hydroxy-2'-Deoxyguanosine; D003849:Deoxyguanosine