Circulating microbiome DNA as biomarkers for early diagnosis and recurrence of lung cancer

Chen H, Ma Y, Xu J, et al. Circulating microbiome DNA as biomarkers for early diagnosis and recurrence of lung cancer. Cell Rep Med. 2024;5(4):101499. doi:10.1016/j.xcrm.2024.101499

This is a summary of our May 3rd, 2024 DalMUG journal club discussion, written by Monica Alvaro Fuss

Summary

This study investigates the diagnostic and prognostic use of circulating microbiome DNA (cmDNA) signatures in lung cancer patients. Early screening and risk assessment is crucial for reducing lunch cancer mortality rates; tumour-associated microbes have been linked to the pathology of several types of cancer, and circulating biomarkers offer an attractive alternative to invasive biopsies. To generate both early detection and postoperative recurrence models, the authors performed whole genome sequencing on plasma samples from either early-stage cancer patients or matched healthy controls – including two validation cohorts, as well as patients that did or did not experience postoperative recurrence within 3 years. Differences in diversity and taxonomic composition of cmDNA were found between cancer patients and healthy controls. Furthermore, the authors state that the early detection and recurrence models exhibited high degrees of accuracy and sensitivity, and identified taxa that have been previously associated with lung cancer development, response and recurrence.

Below are the key points that came up during our discussion.

Points of discussion

  • We discussed how different cohorts came from different hospitals and potential batch effects.

  • Observed species in the early detection model was extremely high.

  • Like many other blood microbiome/circulating DNA studies, many identified taxa are not human-associated.

  • It was not immediately clear that the cancer and recurrence scores used in the study were based on the models. Cancer and recurrence scores are often used in different contexts.

  • Data and methods are said to be publically available but we were not able to access them freely.

Written on May 3, 2024