Biological effects of selective COX-2 inhibitor NS398 on human glioblastoma cell lines

Abstract

Background: Cyclooxygenase-2 (COX-2), an inflammation-associated enzyme, has been implicated in tumorigenesis and progression of glioblastoma (GBM). The poor survival of GBM was mainly associated with the presence of glioma stem cells (GSC) and the markedly inflammatory microenvironment. To further explore the involvement of COX-2 in glioma biology, the effects of NS398, a selective COX-2 inhibitor, were evaluated on GSC derived from COX-2 expressing GBM cell lines, i.e., U87MG and T98G, in terms of neurospheres' growth, autophagy, and extracellular vesicle (EV) release. Methods: Neurospheres' growth and morphology were evaluated by optical and scanning electron microscopy. Autophagy was measured by staining acidic vesicular organelles. Extracellular vesicles (EV), released from neurospheres, were analyzed by transmission electron microscopy. The autophagic proteins Beclin-1 and LC3B, as well as the EV markers CD63 and CD81, were analyzed by western blotting. The scratch assay test was used to evaluate the NS398 influence on GBM cell migration. Results: Both cell lines were strongly influenced by NS398 exposure, as showed by morphological changes, reduced growth rate, and appearance of autophagy. Furthermore, the inhibitor led to a functional change of EV released by neurospheres. Indeed, EV secreted by NS398-treated GSC, but not those from control cells, were able to significantly inhibit adherent U87MG and T98G cell migration and induced autophagy in recipient cells, thus leading to effects quite similar to those directly caused by NS398 in the same cells. Conclusion: Despite the intrinsic diversity and individual genetic features of U87MG and T98G, comparable effects were exerted by the COX-2 inhibitor NS398 on both GBM cell lines. Overall, our findings support the crucial role of the inflammatory-associated COX-2/PGE2 system in glioma and glioma stem cell biology.

Potential surrogate quantitative immunomodulatory potency assay for monitoring human umbilical cord‐derived mesenchymal stem cells production

“…NS‐398 is a specific COX2 inhibitor, which can abrogate COX2‐PGE2 expression (Liu et al, 2020; Palumbo et al, 2020; Wehner et al, 2009). NS‐398, was used to elucidate the mechanism involved in the immunomodulatory ability of hUC‐MSCs.…”

Role of Inflammatory Mediators, Macrophages, and Neutrophils in Glioma Maintenance and Progression: Mechanistic Understanding and Potential Therapeutic Applications

“…IL-1β upregulated mRNA expression of pro-inflammatory prostaglandin COX-2 in glioma cells [31]. COX-2 and its product (PG) E2 interact with four GPCRs-PGE 2 receptors like EP1, EP2, EP3, and EP4, and thereby enhance glioma aggressiveness by maintaining glioma cell stemness and the inflammatory microenvironment [32,33]. IL-1β binds to IL-1 receptor and switches on the NF-kB pathway, leading to persistent stimulation of pro-inflammatory genes [34].…”

ELAVL1 Role in Cell Fusion and Tunneling Membrane Nanotube Formations with Implication to Treat Glioma Heterogeneity

“…COX-2 (an inducible form of the cyclooxygenase enzyme that catalyzes the first step in the synthesis of prostanoids) is overexpressed in gliomas and is an established HuR-mRNA target. COX-2, in combination with PGE2, may influence ROS generation and controls the cellular redox state; therefore, it impacts cell fusion and tunneling membrane nanotube formation [ 63 , 64 ]. Direct COX-2 mRNA stabilization by HuR leading to an increase in COX-2 expression has been demonstrated in breast carcinoma [ 65 ]; also, the constitutive overexpression of COX-2 in ovarian and colon cancers is the result of HuR overexpression [ 63 , 66 ].…”