Casual associations between blood metabolites and colon cancer.

Background: Limited knowledge exists regarding the casual associations linking blood metabolites and the risk of developing colorectal cancer.

Aim: To investigate causal associations between blood metabolites and colon cancer.

Methods: The study utilized a two-sample Mendelian randomization (MR) analysis to investigate the causal impact of 486 blood metabolites on colorectal cancer. The primary method of analysis used was the inverse variance weighted model. To further validate the results several sensitivity analyses were performed, including Cochran's Q test, MR-Egger intercept test, and MR robust adjusted profile score. These additional analyses were conducted to ensure the reliability and robustness of the findings.

Results: After rigorous selection for genetic variation, 486 blood metabolites were included in the MR analysis. We found Mannose [odds ratio (OR) = 2.09 (1.10-3.97), = 0.024], N-acetylglycine [OR = 3.14 (1.78-5.53), = 7.54 × 10], X-11593-O-methylascorbate [OR = 1.68 (1.04-2.72), = 0.034], 1-arachidonoylglycerophosphocholine [OR = 4.23 (2.51-7.12), = 6.35 × 10] and 1-arachidonoylglycerophosphoethanolamine 4 [OR = 3.99 (1.17-13.54), = 0.027] were positively causally associated with colorectal cancer, and we also found a negative causal relationship between Tyrosine [OR = 0.08 (0.01-0.63), = 0.014], Urate [OR = 0.25 (0.10-0.62), = 0.003], N-acetylglycine [0.73 (0.54-0.98), = 0.033], X-12092 [OR = 0.89 (0.81-0.99), = 0.028], Succinylcarnitine [OR = 0.48 (0.27-0.84), = 0.09] with colorectal cancer. A series of sensitivity analyses were performed to confirm the rigidity of the results.

Conclusion: This study showed a causal relationship between 10 blood metabolites and colorectal cancer, of which 5 blood metabolites were found to be causal for the development of colorectal cancer and were confirmed as risk factors. The other five blood metabolites are protective factors.