Inhibition of enzymatic activity of HRD1 results in death of cells derived from glioblastoma multiforme, neuroblastoma, and normal astrocytes.

in Neoplasma by Jaroslava Guzikova, Monika Liskova, Lubos Hudak, Maria Brodnanova, Andrea Evinova, Jozef Hatok, Peter Racay

TLDR

  • The study examined the effects of LS-102, an HRD1 inhibitor, on human cell lines derived from glioblastoma multiforme, neuroblastoma, and astrocytes. Results show that LS-102 induces cell death across all cell lines, with varying sensitivity, and may not be suitable as an antitumor treatment for GBM due to its effect on normal astrocytes.

Abstract

The aim of the present study was to examine the impact of LS-102, an inhibitor of enzymatic activity of HRD1 that is an essential E3 ubiquitin ligase of endoplasmic reticulum associated degradation (ERAD) on survival of the human cell lines derived from glioblastoma multiforme (GBM), neuroblastoma, and astrocytes. We have also examined molecular responses to HRD1 inhibition with a focus on proteins playing an essential role in unfolded protein response (UPR) and ERAD. In addition, activation of IRE1α documented by XBP1 splicing was investigated. Finally, we have examined the impact of LS-102 on p53 expression in GBM cells. Inhibition of HRD1 enzymatic activity results in cell death of all tested cells. With respect to GBM cells, U87 cells are more sensitive to LS-102 as T98G cells. Cells of cell lines derived from normal astrocytes K1884 exhibit the highest sensitivity to LS-102 among all cell types used in the study while NHA cells are the most resistant. Sensitivity of neuroblastoma SH-SY5Y cells to LS-102 is comparable to the sensitivity of U87 cells. In GBM cells, inhibition of HRD1 results in induction of the expression of proteins playing an essential role in UPR and ERAD (HRD1, SEL1L, and GRP78). XBP1 splicing induced by HRD1 inhibition was documented in T98G and K1884 cells. We did not observe induction of p53 expression in U87 cells. Since LS-102 induces cell death of normal astrocytes, it is not a candidate for the testing of its potential use as an antitumor treatment of GBM.

Overview

  • The study aimed to examine the impact of LS-102, an HRD1 inhibitor, on the survival of human cell lines derived from glioblastoma multiforme (GBM), neuroblastoma, and astrocytes.
  • The study also investigated molecular responses to HRD1 inhibition, focusing on proteins involved in unfolded protein response (UPR) and endoplasmic reticulum-associated degradation (ERAD).
  • The study examined the impact of LS-102 on p53 expression in GBM cells and activation of IRE1α by XBP1 splicing.

Comparative Analysis & Findings

  • Inhibition of HRD1 enzymatic activity resulted in cell death of all tested cells, with varying sensitivity across cell lines.
  • GBM cells showed differences in sensitivity, with U87 cells being more sensitive to LS-102 than T98G cells.
  • Normal astrocyte-derived cells (K1884) exhibited the highest sensitivity to LS-102, while NHA cells were the most resistant, and neuroblastoma-derived cells (SH-SY5Y) showed comparable sensitivity to U87 cells.

Implications and Future Directions

  • The study suggests that LS-102 may not be a viable candidate for antitumor treatment of GBM, as it induces cell death in normal astrocytes.
  • Further research is needed to explore alternative applications for HRD1 inhibitors or to develop more targeted approaches.
  • Understanding the molecular responses induced by HRD1 inhibition could provide insights into the development of new therapeutic strategies for cancer treatment.
Read Full Article