The expression of DNAJB9 in normal human astrocytes is more sensitive to nanographene oxide than in glioblastoma cells.

Nanographene oxide (nGO) nanoparticles (NPs) have unique properties and are widely used in various fields, including biomedicine. These NPs, however, also exhibit toxic ef-fects and therefore, the understanding of the molecular mechanism of nGO toxicity is very im-portant mainly for the nanomedicine, especially the cancer therapy. This study aimed to examine the impact of nGO NPs on the expression of genes associated with endoplasmic reticulum (ER) stress, proliferation, and cancerogenesis in both normal human astrocytes and U87MG glioblas-toma cells.

Endoplasmic reticulum stress-dependent regulation of carboxypeptidase E expression in glioblastoma cells.

Carboxypeptidase E (CPE) plays an important role in the biosynthesis of neurotransmitters and peptide hormones including insulin. It also promotes cell proliferation, survival, and invasion of tumor cells. The endoplasmic reticulum stress, hypoxia, and nutrient supply are significant factors of malignant tumor growth including glioblastoma.

Knockdown of ERN1 disturbs the expression of phosphoserine aminotransferase 1 and related genes in glioblastoma cells.

Background: Endoplasmic reticulum stress and synthesis of serine are essential for tumor growth, but the mechanism of their interaction is not clarified yet. The overarching goal of this work was to investigate the impact of ERN1 (endoplasmic reticulum to nucleus signaling 1) inhibition on the expression of serine synthesis genes in U87MG glioblastoma cells concerning the suppression of cell proliferation.

Methods: Wild type U87MG glioblastoma cells and their clones with overexpression of transgenes dnERN1 (without cytoplasmic domain of ERN1) and dnrERN1 (with mutation in endoribonuclease of ERN1), and empty vector (as control) were used.

Inhibition of ERN1 affects the expression of TGIF1 and other homeobox gene expressions in U87MG glioblastoma cells.

Background: The ERN1 (endoplasmic reticulum to nucleus signaling 1) pathway plays an important role in the regulation of gene expression in glioblastoma, but molecular mechanism has not yet been fully elucidated. The aim of this study was to evaluate the relative relevance of ERN1 activity as a kinase in comparison to its endoribonuclease activity in the regulation of homeobox gene expression.

Methods: Two sublines of U87MG glioblastoma cells with different ways of ERN1 inhibition were used: dnERN1 (overexpressed transgene without protein kinase and endoribonuclease) and dnrERN1 (overexpressed transgene with mutation in endoribonuclease).

Endoplasmic reticulum stress-dependent regulation of the expression of serine hydroxymethyltransferase 2 in glioblastoma cells.

Serine hydroxymethyltransferase (SHMT2) plays a multifunctional role in mitochondria (folate-dependent tRNA methylation, translation, and thymidylate synthesis). The endoplasmic reticulum stress, hypoxia, and glucose and glutamine supply are significant factors of malignant tumor growth including glioblastoma. Previous studies have shown that the knockdown of the endoplasmic reticulum to nucleus signaling 1 (ERN1) pathway of endoplasmic reticulum stress strongly suppressed glioblastoma cell proliferation and modified the sensitivity of these cells to hypoxia and glucose or glutamine deprivations.