Glioma SOX2 expression decreased after adjuvant therapy

Area of Science:

• Neuro-oncology
• Cancer Stem Cells
• Molecular Oncology

Background:

• SOX2 is a crucial stem cell marker.
• Its expression changes in high-grade glioma (HGG) after adjuvant therapy are not well understood.
• Recurrent HGG samples are scarce, limiting research.

Purpose of the Study:

• To analyze SOX2 protein expression in paired primary and recurrent HGG.
• To understand SOX2 expression changes following adjuvant therapy in HGG.
• To correlate SOX2 expression patterns with patient prognosis.

Main Methods:

• Immunohistochemistry used to assess SOX2 protein expression in 24 paired primary and recurrent HGG samples.
• Patients included those who underwent a second resection.
• Statistical analysis performed using IBM SPSS Statistics.

Main Results:

• SOX2 was highly expressed in primary HGG (83.3% cases showed 3+ expression).
• SOX2 expression significantly decreased in recurrent HGG compared to primary tumors (p=0.001).
• Decreased SOX2 expression was associated with prior chemotherapy and/or radiotherapy (p=0.003). High SOX2 expression in primary tumors correlated with longer progression-free survival (PFS).
• A decrease in SOX2 expression from primary to recurrent HGG indicated worse prognosis (PFS: 10.4 vs 14.9 months, OS: 27.0 vs 49.5 months).

Conclusions:

• This is the first study to compare SOX2 expression in paired primary and recurrent HGG.
• A tendency for decreased SOX2 expression in recurrent gliomas was observed, particularly after adjuvant therapy.
• Both low SOX2 expression in primary HGG and a decrease in expression upon recurrence are associated with poorer patient outcomes.