Obesity is increasingly recognised as an important factor contributing to cancer progression, particularly in breast cancer. However, the cellular and molecular mechanisms underlying obesity-driven breast cancer remain unclear. Several theories have been proposed to explain the complex interactions between adipose tissue and cancer, incorporating both local and distant crosstalk. This review describes existing theories on the cellular and molecular mechanisms linking obesity and breast cancer progression with a focus on inflammation, oxidative stress, metabolic reprogramming, the tumour microenvironment and crosstalk between adipose tissue and tumours. The nature of these interactions appears to be influenced by the specific characteristics of adipose tissue, including its type and anatomical location, which play distinct roles in modulating breast cancer risk and outcomes. Understanding the cellular and molecular mechanisms that underlie obesity-driven breast cancer progression may pave the way for the development of targeted therapies.
Keywords: adipokines; adipose tissue; breast cancer; cancer metabolism; obesity; oxidative stress; tumour microenvironment.
© 2026 The Author(s). Cell Biochemistry and Function published by John Wiley & Sons Ltd.