Impact of Energy Balance on Chemically Induced Mammary Carcinogenesis in a Rat

Abstract

Energy balance quantifies the amount of energy available to an organism, i.e., its energy exposure over any timeframe of interest. This chapter examines how energy availability impacts the carcinogenic response in a well-defined animal model for breast cancer with demonstrated relevance to the human disease. When animals are in positive energy balance, there is a direct association between the carcinogenic response and energy availability across a broad range of energy inputs. Both host systemic and cell autonomous processes are implicated in accounting for these effects. At the cellular level, the interplay between cell proliferation and apoptosis appears to dictate the rate of tumor mass accumulation with the integration of internal and external inputs regarding energy availability via the signaling network of which the mammalian target of rapamycin is a component. Gaps in the existing knowledge and research opportunities are identified, and new paradigms are presented with the goal of stimulating debate and discussion that will advance the field.