Date Published: January 19, 2017
Publisher: Public Library of Science
Author(s): Rong Wu, Jiafu Feng, Yuwei Yang, Chunmei Dai, Anyang Lu, Jie Li, Yao Liao, Miao Xiang, Qingmei Huang, Dong Wang, Xiao-Bo Du, Reza Khodarahmi.
Oxidative stress is involved in a variety of diseases. Prospective studies investigating the relationship between oxidative stress biomarkers and the status and development of colorectal cancer (CRC) are scarce; previous studies have failed to establish a relationship between the serum total oxidant/antioxidant status and CRC. Therefore, we compared the total serum oxidant/antioxidant levels of CRC patients and healthy subjects, and analyzed their clinical significance in the CRC. Fasting blood samples from 132 CRC patients and 64 healthy subjects were collected. Oxidative stress parameters, including total oxidant status (TOS) and total antioxidant status (TAS), were measured, and the oxidative stress index (OSI) was calculated. The TOS and OSI levels increased significantly (P<0.001) and the TAS level significantly decreased (P<0.001) in the CRC group compared to those in the healthy control group. Oxidative stress parameters differed significantly depending on the patient’s smoking and drinking status (P<0.05). The preoperative and postoperative levels of TOS, TAS, and OSI did not differ significantly between primary sites (colon/rectum) and clinical stages (P>0.05).However, the levels of TOS, TAS, and OSI were significantly different between patients with no metastasis and those with metastases to two organs (P<0.05) Finally, the parameters are affected by smoking and drinking, and subsequent research should be conducted excluding the relevant influencing factors.
Colorectal carcinoma (CRC) is one of the most common malignant tumors, and its morbidity and mortality rates have been increasing annually. The cancer statistics report for 2016 shows that CRC has the third highest incidence and mortality rates among all malignant tumors in developed countries such as the United States .In developing countries such as China, CRC also shows a high incidence rate, and its morbidity and mortality were the fifth highest among all malignant tumors in 2015.The age of disease onset was lower in China than in the United States; disease onset peaked at 60–74 years of age among Chinese patients, while it was 70 years among American patients [1–2].
All subject demographics and clinical data are summarized in Table 1. There were no significant differences in age (P = 0.162), sex (P = 0.159), smoking history (P = 0.086), or drinking history (P = 0.170) between the patients and controls. The serum levels of oxidative stress parameters in CRC patients (group A) and healthy controls (group B) are shown in Table 2.
The incidence and mortality rates of CRC are very high and have been annually increasing worldwide. There have been recent advances in the research of tumor gene engineering technology and molecular biology. The diagnosis and treatment of CRC have significantly improved and treatment is no longer limited to surgery or chemotherapy and radiotherapy, since new treatment methods and drugs are available. Gene-targeted drugs and tumor immunetherapy has been shown to have a certain curative effect and good prospects for development. Despite these advances, the mortality rates for CRC have not decreased and it remains a direct threat to human health. Although many research studies have been conducted, the pathogenesis of CRC has not been fully explained.
We showed that serum oxidative stress parameters (TOS, TAS, and OSI) are correlated with the status of CRC, and we suggest that oxidative stress parameters might indicate the severity of CRC; however, further research is required to confirm these findings. Finally, smoking and drinking are important factors that influence oxidative stress parameters, and subsequent research should be conducted excluding these relevant influencing factors.