Friday Aug 1, 2014 (foodconsumer.org) -- A new study suggests that weight loss induced by a low fat diet may reverse the progression of basal-like breast cancer (BBC), an aggressive form of breast cancer, in obese individuals who follow a high fat obesity promoting diet.

In the study, C3(1)-TAg mice, a life-long model of obesity, were weaved onto and fed an obesogenic high fat diet.  And the obese mice displayed significantly elevated progression of mammary gland tumors which are the same as breast cancers in humans.

When obese mice started to use a control low fat diet prior just to tumor onset to induce weight loss, the tumor progression was significantly reversed.

Researchers observed obesity increased mammary gland expression and activation of hepatocyte growth factor (HGF)/c-Met, a pro-tumorigenic pathway correlated with BBC.  

Epidemiologic studies have already found the tumor-promoting effect of obesity and suggest that weight loss can prevent this basal like type of breast cancer.

Additionally, the current study also found obesity elevated other oncogenic factors such as hyperinsulinemia  (high insulin) and a high leptin to adipnectin ratio and weight loss reduced these factors.

The study concluded "weight loss significantly blunted the obesity-responsive pro-tumorigenic HGF/c-Met pathway and improved several metabolic risk factors associated with BBC (Basal like breast cancer), which together may have contributed to the dramatic reversal of obesity-driven tumor progression."  (David Liu)

Sundaram S, Le TL, Essaid L, Freemerman AJ, Huang MJ, Galanko JA, McNaughton KK, Bendt KM, Darr DB, Troester MA, Makowski L.  Weight Loss Reversed Obesity-Induced HGF/c-Met Pathway and Basal-Like Breast Cancer Progression.  Front Oncol. 2014 Jul 8;4:175.