Non-Invasive Analysis of Tumor DNA in Oral Squamous Cell Carcinoma Patients

Strategic Insights -

Investigators at Universite de Picardie Jules Verne in Amiens, France, have developed a non-invasive method to monitor oral squamous cell carcinoma (OSCC) patients by analyzing tumor DNA in biological fluids, specifically saliva. This approach involves identifying cancer-specific DNA methylation marks in the saliva of OSCC patients. The researchers analyzed DNA methylation in tumor and matched non-tumor tissue, and found five genes with higher methylation levels in OSCC compared to non-tumor tissue. They also found that 70% of OSCC patients had at least one detectable cancer-specific DNA methylation mark in their saliva before surgery.

Key Takeaways:

  • Researchers at Universite de Picardie Jules Verne developed a non-invasive method to monitor OSCC patients by analyzing tumor DNA in saliva.
  • The approach involves identifying cancer-specific DNA methylation marks in the saliva of OSCC patients.
  • Five genes with higher methylation levels in OSCC compared to non-tumor tissue were identified.
  • 70% of OSCC patients had at least one detectable cancer-specific DNA methylation mark in their saliva before surgery.
  • Complete surgical resection led to a significant disappearance of salivary cfDNA methylation marks.
  • 52% of patients showed persistence of at least one mark, related to close/positive surgical margin status.
  • In one patient, recurrence of OSCC was preceded by persistence of ASCL1 methylation by 4 months.
  • The researchers concluded that salivary cfDNA methylation analysis offers a minimally invasive method to monitor the effectiveness of surgical resection of OSCC.

Statistics:

  • 30 OSCC patients were analyzed in the study.
  • 5 genes with higher DNA methylation levels in OSCC compared to non-tumor tissue were identified.
  • 7 patients (70%) had at least one detectable cancer-specific DNA methylation mark in their saliva before surgery.
  • 52% of patients showed persistence of at least one mark after surgery.
  • 1 patient had recurrence of OSCC preceded by persistence of ASCL1 methylation by 4 months.

Sources:

  • Salivary cell-free DNA methylation analysis for oncological monitoring of surgical resection of oral squamous cell carcinoma. Frontiers in Oral Health, 2025,6.
  • Researcher Zuzana Saidak from UR7516, CHIMERE, Universite de Picardie Jules Verne, Amiens, France.
  • Additional authors: Marie Milly, Christophe Louandre, Emilien Colin, Pia-Manuela Rusu, Agnes Paasche, Stephanie Dakpe, Sylvie Testelin, Antoine Galmiche.