Published online Nov 15, 2022. doi: 10.4251/wjgo.v14.i11.2208
Peer-review started: May 4, 2022
First decision: July 13, 2022
Revised: August 19, 2022
Accepted: September 21, 2022
Article in press: September 21, 2022
Published online: November 15, 2022
Processing time: 195 Days and 4.5 Hours
The role of oxidative stress in the pathogenesis of colorectal cancer (CRC) has recently attracted considerable interest. Specific oxidative factors have been implicated in the pathogenesis of adenomatous polyps and ultimately adenocarcinoma.
Several studies have evaluated the association between oxidative imbalance and the development of colorectal adenocarcinoma although the results are conflicting. Thus, the study was designed to assess the correlation between the dietary intake habits of individuals with either colonic polyps or CRC through measurements of oxidant/antioxidant serological markers aiming to introduce novel serum indicators of colonic cancer even in the stage of aberrant crypt foci.
The main objective of the study was to evaluate the effect of total oxidant activity and antioxidant capacity in the development of sporadic colon adenocarcinoma.
A total of 170 patients that underwent endoscopy of the lower gastrointestinal tract in a tertiary center within 3 years were included in the study. They were allocated in three groups; those with sporadic colon adenocarcinoma (n = 56, 32.9%), those with colonic polyps (n = 33, 19.4%) and healthy controls (n = 81, 47.7%). All patients were evaluated for oxidant activity and antioxidant capacity with serum measurements of specific markers such as vitamins A, 25(OH) D3, E, C, B12, folic acid, glutathione, selenium (Se), zinc (Zn), free iron (Fe2+) and malondialdehyde and results were compared between groups.
Serum levels of vitamins C, E, D, Se, Zn, vitamin B12 and total antioxidant capacity were significantly lower in the combined neoplasia/polyp group than in the control group (P = 0.002, P = 0.009, P < 0.001, P < 0.001, P < 0.001, P = 0.020 and P < 0.001, correspondingly). Increased levels of vitamin E (P = 0.004), vitamin D (P < 0.001), Se (P < 0.001) and Zn (P < 0.001) seem to bestow a protective effect on the development of CRC. For vitamin D (P < 0.001) and Zn (P = 0.036), this effect seems to extend to the development of colon polyps as well. On the other hand, elevated serum levels of malondialdehyde are associated with a higher risk of CRC (OR = 2.09 compared to controls, P = 0.004). Regarding colonic polyp development, increased concentrations of vitamin Α and Fe2+ are associated with a higher risk whereas lower levels of malondialdehyde with a lower risk.
In conclusion, increased oxidative stress may play an essential role in the pathogenesis and progression of CRC. Antioxidants’ presence may exert a protective effect in the early stages of colon carcinogenesis.
Further research in high-risk CRC populations is needed in order to assess the role of oxidative imbalance in the development of CRC and the potential for colonic cancer by dietary modifications regarding specific oxidative serum markers.