Clinical Evaluation of Proline, Glutamic acid, and Leucine-Rich Protein 1 Expression in Astrocytomas and Correlations with the Proliferation Marker Ki-67

Malignant astrocytomas presenting in humans of any age group are a challenge to diagnose and treat. Hence, there is a quest for new markers to ascertain their grades and predict disease outcomes. Proline, glutamic acid, and leucine-rich protein 1 (PELP1), a nuclear receptor co-regulator, is an oncogene found in various cancers. We postulate that by screening for PELP1, its correlation with survival outcomes of patients across various grades can indicate a plausible novel diagnostic marker and a potential therapeutic target in gliomas. Immunostaining of 100 cases of astrocytomas for PELP1 was performed on paraffin-embedded sections. Results showed that PELP1 expression increases with higher grades; the mean H-score of PELP1 in grade-I astrocytomas was determined to be 112.3, whereas in grade-IV it was 235.1 (P value = 0.0001). Survival analysis of patients with H-score of 200-300 was only 8.8% and 68.8% in patients with scores of 0-100. PELP1 expression in high-grade astrocytomas is an important factor in determining the outcomes. Graphical abstract Evaluation of molecular expression of PELP1 along with Ki-67 LI signifies a linear increase in its expression pattern among different grades of astrocytomas from low- to high-grade tumors, which can serve as a potential prognostic molecular marker in differentiating various types of astrocytomas in humans.

Keywords: Astrocytomas; Clinicopathological characteristics; H-score; IHC; Ki-67 LI; PELP1.