Night shift work, DNA methylation and telomere length: An investigation on hospital female nurses

Michele Carugno, Cristina Maggioni, Eleonora Crespi, Matteo Bonzini, Simone Cuocina, Laura Dioni, Letizia Tarantini, Dario Consonni, Luca Ferrari, Angela Cecilia Pesatori

Research output: Contribution to journalArticlepeer-review


Increased breast cancer risk has been reported in some night shift (NS) workers but underlying biological mechanisms are still unclear. We assessed the association between NS work and DNA methylation of tumor suppressor (TP53, CDKN2A, BRCA1, BRCA2) and estrogen receptor (ESR1, ESR2) genes, methylation of repetitive elements (LINE-1, Alu), and telomere length (TL). Forty six female nurses employed in NS for at least two years were matched by age (30–45 years) and length of service (≥1 year) with 51 female colleagues not working in NS. Each subject underwent a semi-structured interview and gave a blood sample. We applied linear regression and spline models adjusted for age, BMI, smoking habit, oral contraceptive use, parity and marital status/age at marriage. Currently working in NS was associated with ESR1 hypomethylation (β: -1.85 (95%CI: -3.03; -0.67), p = 0.003). In current and former NS workers we observed TP53 (-0.93 (-1.73; -0.12), p = 0.03) and BRCA1 (-1.14 (-1.71; -0.58), p <0.001) hypomethylation. We found an increase between TL and number of years in NS in subjects employed in NS <12 years (0.06 (0.03; 0.09), p <0.001), while a decrease if employed in NS ≥12 years (-0.07 -0.10; -0.04), p <0.001). Our findings show NS-ssociated markers potentially involved in cellular aging, genomic instability, and cancer development.

Original languageEnglish
Article number2292
JournalInternational Journal of Environmental Research and Public Health
Issue number13
Publication statusPublished - Jul 1 2019


  • Breast cancer
  • DNA methylation
  • Female nurses
  • Night shift work
  • Telomere length

ASJC Scopus subject areas

  • Public Health, Environmental and Occupational Health
  • Health, Toxicology and Mutagenesis


Dive into the research topics of 'Night shift work, DNA methylation and telomere length: An investigation on hospital female nurses'. Together they form a unique fingerprint.

Cite this