Sexual behavior and risk of cancers; a TWO-SAMPLE mendelian randomization study of European Ancestry
Lin Zhou, Qiang Wang, Qian Xu, Huiyu Gao, Jiabin Zhang, Ying Tan, Xinru Hu, Meng Chen, Ziyuan Luo, Xiang Cai, Shan Wang, Xi Duan, Tao WuBackground
The relationship between sexual behavior and cancers is intricate. It remains controversial, and we aimed to comprehensively explore the relationship between sexual behavior and cancers.
Methods
We selected age first had sexual intercourse (AFSI) and the lifetime number of sexual partners (LNSP) to represent sexual behavior. The data for the genome-wide association studies (GWAS) of sexual behavior and cancers were obtained from the IEU Open GWAS summary database, and the results were also validated with data on cancers from the FinnGen biobank. The causal effects were computed using inverse variance weighting, the MR-Egger approach, and the weighted median method; moreover, the Bonferroni correction was employed to preclude potential errors arising from multiple tests. To ensure the robustness of the findings, sensitivity analyses were conducted using Cochran’s Q test, the MR-Egger intercept test, MR-PRESSO, leave-one-out analysis, and funnel plots. Furthermore, reverse Mendelian randomization was employed to ascertain that no confounding bias was introduced by reverse causation. In the end, a meta-analysis was employed to integrate the data from the two databases for a combined analysis.
Results
Our study demonstrated that after Bonferroni correction, AFSI was negatively associated with the risk of oral cavity cancer and positively associated with the risk of prostate cancer. No causal associations between AFSI or LNSP and other cancers, including colorectal, breast, bladder, cervical, and thyroid cancers, were observed.
Conclusion
Our study demonstrates that genetically predicted AFSI has the potential to be causally related to oral and prostate cancers, thereby providing new insights into the field of preventive cancer care.