OBESITY is linked to greater risk for numerous cancers. Indeed, the American Cancer Society states that it can trigger changes in hormones that lead to renal cell carcinoma, the most common form of kidney cancer. Nevertheless, a recent study has suggested that overweight and obese patients with kidney cancer have significantly increased survival chances. This contrasts with many other forms of cancer, where obesity following a cancer diagnosis has been associated with poorer prognosis.
The link between weight and kidney cancer survival was explored through the analysis of data from four medical databases. Analysis of data from 1,975 patients from the International Metastatic Renal Cell Carcinoma Database Consortium revealed that patients with a low BMI lived an average of 17.1 months, while patients with a high BMI lived for 25.6 months on average.
Bearing this in mind, clinical and genomic information from 324 patients with kidney cancer and tissue samples from 146 patients was studied to discern whether there were any molecular differences between kidney cancer patients with a low or high BMI that could explain the difference in survival rates. Based on the tissue sample analysis, it was found that those patients with a high BMI had reduced expression of the fatty acid synthase gene (FASN). Overexpression of this gene has been linked to several types of cancer, as well as to poor outcomes in kidney cancer patients.
Therefore, the researchers conjectured that reduced expression of FASN may be the reason why those kidney cancer patients who are overweight or obese live longer than patients who are underweight or of a healthy weight. This offers potential for treatment by blocking FASN, with FASN inhibitors already in the process of development. The senior author of the study, Prof Toni Choueiri, Dana-Farber Cancer Institute, Boston, Massachusetts, USA, said: “We plan to test FASN inhibitors in an animal model as a possible therapy for kidney cancer.”