Will higher Selenium status prevent Cancer risk?

According to a new study, having a high selenium level may not prevent the development of cancer. The links between kidney cancer and multiple myeloma must be confirmed in well-powered investigations.

As the evidence for a link between selenium and cancer risk is ambiguous, this study was conducted by Shuai Yuan and team with the objective to investigate the links between selenium levels and 22 different types of cancer, as well as any cancer.

The findings of this study were published in the International Journal of Cancer on 15 December, 2021.

For this study, as instrumental variables, single nucleotide polymorphisms highly related with toenail and blood (TAB) and blood selenium levels in mild linkage disequilibrium (r2 0.3) were utilized. The UK Biobank was used to obtain genetic correlations of selenium-associated single nucleotide polymorphisms with cancer, which included 59,647 cancer cases and 307,914 controls. Associations with p0.1 in the UK Biobank were evaluated for replication in the FinnGen collaboration, which included over 180,000 people. The relationships were estimated using the inverse-variance weighted technique, which accounts for linkage disequilibrium.

The results stated as follow:

1. TAB selenium levels predicted by genetics were not linked with the risk of the 22 site-specific malignancies or any cancer (all 22 site-specific cancers).

2. Similarly, there was no meaningful correlation found between genetically predicted blood selenium levels.

3. However, genetically predicted blood selenium levels were associated with an increased risk of kidney cancer (odds ratio (OR) per one-unit rise in log-transformed levels, 0.83, 95% CI, 0.67-1.03) and multiple myeloma (OR, 1.40, 95% CI, 1.02-1.93).

4. FinnGen found the same direction of connection for kidney cancer but not for multiple myeloma.

5. The OR of kidney cancer in the UK Biobank and FinnGen meta-analysis was 0.83. (95 % CI, 0.69-1.00).

In conclusion, overall findings suggest no preventive effect of high selenium status against cancer development.

Reference:

Yuan S, Mason AM, Carter P, Vithayathil M, Kar S, Burgess S, Larsson SC. Selenium and cancer risk: wide-angled Mendelian randomization analysis. Int J Cancer. 2021 Dec 15. doi: 10.1002/ijc.33902. Epub ahead of print. PMID: 34910310.