Exploring the mechanisms linking sleep patterns and breast cancer risk

This INSPIRE project aims to identify blood proteins that mediate the effect of chronotype and breast cancer risk using Mendelian randomisation study design.

  • Topic: Breast cancer
  • Institution: University of Hong Kong
  • Country: Hong Kong
  • Status: Ongoing
Researcher: Shan Luo

INSPIRE grant title: Identify druggable proteins of the association of chronotype on breast cancer using Mendelian randomisation

> More about our INSPIRE Research Challenge

Emerging evidence consistently indicates that a morning chronotype may protect against breast cancer. However, modifying one’s chronotype can be challenging, as it represents an individual’s natural inclination, and people often need to adhere to daily routines that might not align with their biological chronotype in contemporary societies.


We are grateful to the World Cancer Research Fund for supporting our research, which aims to identify druggable proteins, offering alternative and viable interventions for breast cancer prevention and treatment when optimal chronotypes cannot be achieved. – Dr Shan Luo


Emerging evidence consistently shows that a morning chronotype, which is the natural preference of the body to sleep and wake early, protects against breast cancer.

However, the biological mechanisms underlying the relationship remain poorly understood. This limits the ability to identify intervention targets which are particularly relevant for subpopulations where chronotypes are difficult to change (eg night shifts).


This study will apply Mendelian randomisation, which is a type of analysis that looks at genetic data from different studies, to explore whether there is a connection between chronotype (ie sleep patterns) and proteins in the body, and if those proteins influence the risk of breast cancer.


There are proteins in the blood that mediate the effect of chronotypes on breast cancer risk, and hence drugs that target (and reduce the levels of) these proteins can potentially be used to counteract subsequent breast cancer risk.


Identify proteins in the blood that mediate the effect of chronotype and breast cancer risk using a 2-step Mendelian randomisation study design.


This research will enhance our understanding of the biological mechanisms between chronotype and breast cancer. Since a person’s chronotype is difficult to modify in modern society due to night shifts, business travel etc, this study could provide an additional assessment of the potential of taking supplements or medication to adjust one’s misaligned chronotype and improve breast cancer prevention and treatment.