Association of sedentary behavior with the expression levels of biomarkers in colorectal cancer: clinical analysis of 228 patients.

There is an association between sedentary behavior and the risk of colorectal cancer (CRC), but the underlying mechanism is unclear. CRC is characterized by the changes in the expression levels of biomarkers, including voltage-gated proton channel Hv1, matrix-remodeling associated 5 (MXRA5), DEK (inducing positive supercoils into circular DNA) and protein inhibitor of activated signal transducer and activators of transcription 3 (PIAS3). Thus, sedentary behavior may affect the expression levels of these biomarkers in the colorectal tissue. Here, we recruited 228 CRC patients (128 males, 57.8 ± 7.8 years; 100 females, 57.7 ± 7.5 years) and 80 healthy subjects (48 males, 57.5 ± 6.8 years; 32 females, 56.9 ± 6.5 years) from March 7th, 2010 to May 6th, 2012. All the subjects were unrelated Han Chinese with the similar cultural and economic background. All the subjects were interviewed concerning sedentary time (sitting time categories: less than 1, 1-3, 4-6, and more than 6 h/day). The daily sedentary time of most CRC patients was more than 4 h/day, while the sedentary time of most healthy subjects was less than 3 h/day. The expression levels of Hv1, MXRA5 and DEK mRNAs and proteins were higher in CRC tissues and the levels of PIAS3 mRNA and protein were lower when the daily sedentary time was longer in CRC patients (p < 0.05). The daily sedentary time was correlated with the protein levels of CRC biomarkers. Furthermore, the sedentary time was positively related with body mass index but not daily calorie intake.