Previous studies have not been able to establish a clear relationship between ω-3⁄6 and kidney cancer. However, an in vitro study of RCC cell lines showed that PUFAs like EPA and DHA can reduce the invasiveness of cells by upregulating TIMP-1. Additionally, a quantitative analysis of serum from 112 RCC patients indicated that those with metastatic disease had lower levels of DHA than those without. On the other hand, a U.S. population cohort study reported an increased risk of RCC with higher dietary intake of animal fat, saturated fat, oleic acid, and cholesterol. Moreover, a pooled analysis of 13 prospective studies found a significant positive association between polyunsaturated fat intake and the incidence of RCC. Therefore, further research is needed to fully understand the complex relationship between ω-3⁄6 and kidney cancer.
