Aldehyde dehydrogenase 1 expression has prognostic significance in patients with glioma.

As a cancer stem cell marker associated with tumorigenesis, aldehyde dehydrogenase 1 (ALDH1) has recently been identified in gliomas. However, an insufficient number of clinical studies have been published to demonstrate its prognostic significance in glioma. In the present study, a systematic meta-analysis was performed to comprehensively evaluate the correlation of ALDH1 with age, sex, the World Health Organization (WHO) grade, and overall survival (OS) in patients with glioma. A search of relevant publications was conducted to select eligible studies on this subject, and the pooled hazard ratios (HRs) and related risks (RRs) with 95% confidence intervals (95% CIs) were assessed. Publication bias was also evaluated using Begg's funnel plots. A total of 6 articles were identified that included a total of 1,057 patients. OS analysis revealed that a high expression of ALDH1 was significantly associated with poor 5-year OS (n=6; HR, 2.10; 95% CI, 1.13-3.91; P<0.0001), and a high WHO grade (III+IV; n=4; RR, 2.28; 95% CI, 1.31-3.99; P=0.001). In conclusion, a high expression of ALDH1 is associated with a high WHO grade of gliomas and a worse prognosis in patients with glioma. Further, well-designed clinical studies are required to confirm its role in the process of selecting a suitable therapeutic approach in glioma.