Obesity may affect kidney cancer recurrence

Receptors for leptin, a protein hormone, may be associated with tumor recurrence in patients with renal cell carcinoma (RCC), providing further understanding about molecular links between obesity and RCC tumor formation and prognosis, according to a MD Anderson study.

The leptin receptors, called LEPR, were found to be hypermethylated in tumors in study participants. Methylation is a process by which cells control gene expression. Both hypomethylation and hypermethylation are known to play roles in silencing tumor suppressor genes or over-expressing oncogenes in cancer cells. LEPR was one of 20 obesity-related genes that the research team examined.

“Obesity is an established risk factor for RCC with more than 40 percent of these cases attributed to excessive body weight,” said Xifeng Wu, M.D., Ph.D., professor of Epidemiology and principal investigator for the study. “Growing evidence suggests that obesity also may be associated with the prognosis of RCC. The molecular mechanism LEPR and two other genes, NPY and LEP, are involved in RCC tumorigenesis. LEPR methylation in tumors is associated with recurrence in RCC patients and thus, LEPR may provide a functional link between obesity and RCC.”

“Patients were classified into high- and low-LEPR methylation groups,” said Julia Mendoza-Perez, Ph.D., a visiting scientist of Epidemiology at MD Anderson. “We found that high LEPR methylation was associated with a significantly higher risk of tumor recurrence.”

The findings were presented at the annual meeting of the American Association of Cancer Research held recently in New Orleans.

Learn more about this study on MD Anderson's website.