Dynamic interplay between corticosteroid treatment and the role of SRC-1 gene dysregulation in the progression of WHO-Grade 4 Astrocytoma

Background: Corticosteroid is commonly used before surgery to control cerebral oedema in brain tumours and is frequently continued throughout treatment. Its long-term effect of on the recurrence of WHO-Grade 4 astrocytoma remains controversial. The interaction between corticosteroid, SRC-1 gene and cytotoxic T-cells has never been investigated.

Methods: A retrospective cohort of 36 patients with WHO-Grade 4 astrocytoma were examined for CD8 + T-cell and SRC-1 gene expressions through IHC and qRT-PCR. The impact of corticosteroid on CD8⁺T-cells infiltration, SRC-1 expression, and tumour recurrence was analyzed.

Results: The mean patients age was 47-years, with a male to female ratio 1.2. About 78% [n = 28] of the cases showed reduced or no CD8⁺T-cell expression while 22% [n = 8] of cases have showed medium to high CD8⁺T-cell expression. SRC-1 gene was upregulated in 5 cases [14%] and 31 cases [86%] showed SRC-1 downregulation. The average of total days and doses of administered corticosteroid from the preoperative period to the postoperative period was at range of 14-106 days and 41-5028 mg, respectively. There was no significant statistical difference in RFI among tumours expressing high or low CD8⁺T-cells when corticosteroid was administered in recommended or exceeded doses [p-value = 0.640]. There was a significant statistical difference in RFI between CD8⁺T-Cell expression and SRC-1 gene dysregulation [p-value = 002]. Tumours with high CD8⁺T T-cell expression and SRC-1 gene downregulation had late recurrence.

Conclusions: Corticosteroid treatment can directly affect the SRC-1 gene regulation but does not directly influence cytotoxic T-cells infiltration or tumor progression. However, SRC-1 gene downregulation can facilitate late tumor recurrence.