Glioblastoma Relapses Show Increased Markers of Vulnerability to Ferroptosis

Abstract

BackgroundDespite the availability of various therapy options and being a widely focused research area, the prognosis of glioblastoma (GBM) still remains very poor due to therapy resistance, genetic heterogeneity and a diffuse infiltration pattern. The recently described non-apoptotic form of cell death ferroptosis may, however, offer novel opportunities for targeted therapies. Hence, the aim of this study was to investigate the potential role of ferroptosis in GBM, including the impact of treatment on the expression of the two ferroptosis-associated players glutathione-peroxidase 4 (GPX4) and acyl-CoA-synthetase long-chain family number 4 (ACSL4). Furthermore, the change in expression of the recently identified ferroptosis suppressor protein 1 (FSP1) and aldehyde dehydrogenase (ALDH) 1A3 was investigated.MethodsImmunohistochemistry was performed on sample pairs of primary and relapse GBM of 24 patients who had received standard adjuvant treatment with radiochemotherapy. To identify cell types generally prone to undergo ferroptosis, co-stainings of ferroptosis susceptibility genes in combination with cell-type specific markers including glial fibrillary acidic protein (GFAP) for tumor cells and astrocytes, as well as the ionized calcium-binding adapter molecule 1 (Iba1) for microglial cells were performed, supplemented by double stains combining GPX4 and ACSL4.ResultsWhile the expression of GPX4 decreased significantly during tumor relapse, ACSL4 showed a significant increase. These results were confirmed by analyses of data sets of the Cancer Genome Atlas. These profound changes indicate an increased susceptibility of relapsed tumors towards oxidative stress and associated ferroptosis, a cell death modality characterized by unrestrained lipid peroxidation. Moreover, ALDH1A3 and FSP1 expression also increased in the relapses with significant results for ALDH1A3, whereas for FSP1, statistical significance was not reached. Results obtained from double staining imply that ferroptosis occurs more likely in GBM tumor cells than in microglial cells.ConclusionOur study implies that ferroptosis takes place in GBM tumor cells. Moreover, we show that recurrent tumors have a higher vulnerability to ferroptosis. These results affirm that utilizing ferroptosis processes might be a possible novel therapy option, especially in the situation of recurrent GBM.

An update on the therapeutic implications of long-chain acyl-coenzyme A synthetases in nervous system diseases

“…The chemical inhibition, stable silencing, or depletion of ACSL4 demonstrated it can diminish necrosis and aggressiveness of glioblastoma (Yee et al, 2020). However, in the recurrent glioma, the expression of ACSL4 was found significantly increased, indicating glioblastoma relapses may be higher vulnerable to ferroptosis (Kram et al, 2022). Catalyzes the conversion of long-chain FA to acyl-CoAs for both synthesis of cellular lipids Preferred substrates: oleic acid and linoleic acid (Kanter et al, 2012) Glioma (Wang et al, 2018;Zhou et al, 2019;Xu et al, 2022) Amyotrophic lateral sclerosis (ALS) (Ben-Zaken et al, 2022) ACSL3…”

“…Modulates prostaglandin E2 secretion. Preferred substrates: arachidonate (Klett et al, 2017) Central nervous system Glioma (Zhou et al, 2019;Cheng et al, 2020;Tan et al, 2020;Yee et al, 2020;Yi et al, 2020;Dattilo et al, 2021;Hacioglu and Kar, 2022;Kram et al, 2022;Miao et al, 2022) Cerebrovascular diseases: ischemic stroke (Gubern et al, 2013;Li et al, 2019;Chen J. et al, 2021;Cui et al, 2021;Guo H. et al, 2021;Li C. et al, 2021;Liao et al, 2021;Tuo et al, 2022), hemorrhage (Chen B. et al, 2021;Jin et al, 2021), subarachnoid hemorrhage (Qu et al, 2021;Huang et al, 2022;Yuan et al, 2022) Injury: traumatic brain injury (Kenny et al, 2019;Xiao et al, 2019;Bao Z. et al, 2021), spinal cord injury (Zhou et al, 2020;Pang et al, 2022) Intellectual disability: non-syndromic X-Linked intellectual developmental disorder (Meloni et al, 2009;Zhang et al, 2009;Liu et al, 2011Liu et al, , 2014Huang et al, 2016;Chang et al, 2019;Jia et al, 2019), Alport syndrome with intellectual disability (Rodriguez et al, 2010;Smetana et al, 2021) Neurodegenerative diseases: Alzheimer's disease (AD) (Rapoport, 2008;…”

“…The chemical inhibition, stable silencing, or depletion of ACSL4 demonstrated it can diminish necrosis and aggressiveness of glioblastoma ( Yee et al, 2020 ). However, in the recurrent glioma, the expression of ACSL4 was found significantly increased, indicating glioblastoma relapses may be higher vulnerable to ferroptosis ( Kram et al, 2022 ).…”

Ferroptosis Modulation: Potential Therapeutic Target for Glioblastoma Treatment

“…FSP1 works as an oxidoreductase reducing ubiquinone (Coenzyme Q10) to its antioxidant form ubiquinol (CoQH2), which acts as a lipophilic radical scavenger that limits the lipid peroxide accumulation in the absence of GPX4, or complementary to GPX4 activity [75]. Interestingly, pharmacological inhibitors of FSP1 such as iFSP1 synergizes with GPX4 modulation to trigger ferroptosis in FSP1 overexpressed cells [76,77], and iFSP1 can sensitize several cancer cells to ferroptosis [78]. Similarly, dihydroorotate dehydrogenase (DHODH) has also demonstrated an anti-ferroptotic role by regulating ubiquinol activity, inhibiting lipid peroxidation and suppressing ferroptosis induction [79].…”

Ferroptosis: A novel therapeutic strategy and mechanism of action in glioma

“…Conversely, activation of the p38 and ERK pathways in GBM decreased the levels of GPX4 protein (76). Helena Kram et al (77) performed immunohistochemistry on sample pairs of primary and relapse GBM of 24 patients who had received standard adjuvant treatment with radiochemotherapy. They found that the expression of GPX4 decreased significantly during tumor relapse.…”