scholarly journals Elevated cellular PpIX potentiates sonodynamic therapy in a mouse glioma stem cell-bearing glioma model by downregulating the Akt/NFkB/MDR1 pathway

Author(s):  
Yoshifumi Mizobuchi ◽  
Kenji Shono ◽  
Izumi Yamaguchi ◽  
Kohei Nakajima ◽  
Yuri Fujiwara ◽  
...  

Abstract Glioblastoma (GBM) has high mortality rates because of extremely therapeutic resistance. During surgical resection for GBM, 5-aminolevulinic acid (5-ALA)-induced protoporphyrin IX (PpIX) fluorescence is conventionally applied to distinguish GBM. However, surgical intervention is insufficient for high invasive GBM. Sonodynamic therapy (SDT) is an emerging and promising approach combined with low-intensity ultrasonication (US) and PpIX as a sonosensitizer for cancer, whereas its efficacy is limited. Based on our previous study that down-regulation of multidrug resistant protein (MDR1) in GBM augmented anti-tumor effects of chemotherapy, we hypothesized that elevation of cellular PpIX levels by down-regulation of MDR1 enhances anti-tumor effects by SDT. In high invasive progeny cells from mouse glioma stem cells (GSCs) and a GSC-bearing mouse glioma model, we assessed the anti-tumor effects of SDT with a COX-2 inhibitor, celecoxib. Down-regulation of MDR1 by celecoxib increased cellular PpIX levels, as well as valspodar, a MDR1 inhibitor and augmented anti-tumor effects of SDT. MDR1 down-regulation via Akt/NF-kB pathway by celecoxib was confirmed, using a NF-kB inhibitor, CAPÉ. Thus, elevation of cellar PpIX by down-regulation of MDR1 via Akt/NF-kB pathway may be crucial to potentiate the efficacy of SDT in a site-directed manner and provide a promising new therapeutic strategy for GBM.

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Kenji Shono ◽  
Yoshifumi Mizobuchi ◽  
Izumi Yamaguchi ◽  
Kohei Nakajima ◽  
Yuri Fujiwara ◽  
...  

AbstractGlioblastoma (GBM) has high mortality rates because of extreme therapeutic resistance. During surgical resection for GBM, 5-aminolevulinic acid (5-ALA)-induced protoporphyrin IX (PpIX) fluorescence is conventionally applied to distinguish GBM. However, surgical intervention is insufficient for high invasive GBM. Sonodynamic therapy (SDT) combined with low-intensity ultrasonication (US) and PpIX, as a sonosensitizer, is an emerging and promising approach, although its efficacy is limited. Based on our previous study that down-regulation of multidrug resistant protein (MDR1) in GBM augmented the anti-tumor effects of chemotherapy, we hypothesized that elevation of cellular PpIX levels by down-regulation of MDR1 enhances anti-tumor effects by SDT. In high invasive progeny cells from mouse glioma stem cells (GSCs) and a GSC-bearing mouse glioma model, we assessed the anti-tumor effects of SDT with a COX-2 inhibitor, celecoxib. Down-regulation of MDR1 by celecoxib increased cellular PpIX levels, as well as valspodar, an MDR1 inhibitor, and augmented anti-tumor effects of SDT. MDR1 down-regulation via the Akt/NF-κB pathway by celecoxib was confirmed, using an NF-κB inhibitor, CAPÉ. Thus, elevation of cellar PpIX by down-regulation of MDR1 via the Akt/NF-κB pathway may be crucial to potentiate the efficacy of SDT in a site-directed manner and provide a promising new therapeutic strategy for GBM.


2021 ◽  
Vol 23 (Supplement_6) ◽  
pp. vi174-vi174
Author(s):  
Luana Schaab ◽  
Yann Ferry ◽  
Mehmet Ozdas ◽  
Bettina Kritzer ◽  
Sulayman Mourabit ◽  
...  

Abstract Diffuse midline glioma (DMG) is a devastating and incurable childhood brain cancer. With a median survival of only 9 to 11 months, over 90% of children affected by DMG die within two years of diagnosis. Despite decades of research and a growing understanding of the biology of these tumors, there have been no advancements in therapies for DMGs. Tumor heterogeneity and diffuse infiltration in inoperable brain regions make these tumors uniquely difficult to manage both surgically and pharmacologically. Therefore, there is an urgent need for the exploration of novel treatment regimens. Focused Ultrasound (FUS) is an emerging technology with significant clinical potentials. Sonodynamic therapy (SDT) is an up-and-coming treatment strategy aiming to non-invasively eliminate tumor cells by acting through compounds known as sonosensitizers, which render tumor cells sensitive to ultrasound energy. Recently, 5-Aminolevulinic acid (5-ALA), an FDA-approved molecule, has been proposed as a sono-sensitizing agent. 5-ALA mediated SDT prolonged survival in C6 rat glioma models by selective elimination of tumor cells upon sonication. Mechanistically, it is thought that 5-ALA uptake and metabolic conversion into Protoporphyrin IX (PpIX) occurs preferentially in tumor cells due to differential activity of enzymes involved in heme metabolism. Here, we investigated SDT in DMG cells treated with 5-ALA. PpIX fluorescence increased linearly up to 24 h upon 5-ALA treatment and accumulated significantly more (1.6-fold, p < 0.01) when compared to C6 cells. Consequently, FUS sonication of 5-ALA treated DMG cells at 250 kHz significantly (p < 0.05) decreased DMG cell viability compared to treatment with 5-ALA or FUS alone. Here, we show the first 5-ALA mediated sonodynamic effect in DMG cells, leading to enhanced cell death. Our findings provide a rationale for considering clinical investigation of 5-ALA mediated sonodynamic therapy in DMG.


2021 ◽  
Vol 7 (3) ◽  
pp. eabd9440
Author(s):  
Sefan Asamitsu ◽  
Yasushi Yabuki ◽  
Susumu Ikenoshita ◽  
Kosuke Kawakubo ◽  
Moe Kawasaki ◽  
...  

Fragile X-related tremor/ataxia syndrome (FXTAS) is a neurodegenerative disease caused by CGG triplet repeat expansions in FMR1, which elicit repeat-associated non-AUG (RAN) translation and produce the toxic protein FMRpolyG. We show that FMRpolyG interacts with pathogenic CGG repeat-derived RNA G-quadruplexes (CGG-G4RNA), propagates cell to cell, and induces neuronal dysfunction. The FMRpolyG polyglycine domain has a prion-like property, preferentially binding to CGG-G4RNA. Treatment with 5-aminolevulinic acid, which is metabolized to protoporphyrin IX, inhibited RAN translation of FMRpolyG and CGG-G4RNA–induced FMRpolyG aggregation, ameliorating aberrant synaptic plasticity and behavior in FXTAS model mice. Thus, we present a novel therapeutic strategy to target G4RNA prionoids.


2010 ◽  
Vol 86 (2) ◽  
pp. 471-475 ◽  
Author(s):  
Pablo A. Valdés ◽  
Kimberley Samkoe ◽  
Julia A. O’Hara ◽  
David W. Roberts ◽  
Keith D. Paulsen ◽  
...  

2006 ◽  
Vol 82 (6) ◽  
pp. 1638 ◽  
Author(s):  
Ingrid A. Boere ◽  
Dominic J. Robinson ◽  
Henriette S. de Bruijn ◽  
Jolanda Kluin ◽  
Hugo W. Tilanus ◽  
...  

Author(s):  
Stefan Kristiansson ◽  
Asta Juzeniene ◽  
Petras Juzenas ◽  
Vladimir Iani ◽  
Lennart Löfgren ◽  
...  

Biomedicines ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 153
Author(s):  
Nikita G. Nikiforov ◽  
Anastasia Ryabova ◽  
Marina V. Kubekina ◽  
Igor D. Romanishkin ◽  
Kirill A. Trofimov ◽  
...  

Atherosclerosis is associated with a chronic local inflammatory process in the arterial wall. Our previous studies have demonstrated the altered proinflammatory activity of circulating monocytes in patients with atherosclerosis. Moreover, atherosclerosis progression and monocyte proinflammatory activity were associated with mitochondrial DNA (mtDNA) mutations in circulating monocytes. The role of mitochondria in the immune system cells is currently well recognized. They can act as immunomodulators by releasing molecules associated with bacterial infection. We hypothesized that atherosclerosis can be associated with changes in the mitochondrial function of circulating monocytes. To test this hypothesis, we performed live staining of the mitochondria of CD14+ monocytes from healthy donors and atherosclerosis patients with MitoTracker Orange CMTMRos dye, which is sensitive to mitochondrial membrane potential. The intensity of such staining reflects mitochondrial functional activity. We found that parts of monocytes in the primary culture were characterized by low MitoTracker staining (MitoTracker-low monocytes). Such cells were morphologically similar to cells with normal staining and able to metabolize 5-aminolevulinic acid and accumulate the heme precursor protoporphyrin IX (PplX), indicative of partially preserved mitochondrial function. We assessed the proportion of MitoTracker-low monocytes in the primary culture for each study subject and compared the results with other parameters, such as monocyte ability to lipopolysaccharide (LPS)-induced proinflammatory activation and the intima-media thickness of carotid arteries. We found that the proportion of MitoTracker-low monocytes was associated with the presence of atherosclerotic plaques. An increased number of such monocytes in the primary culture was associated with a reduced proinflammatory activation ability of cells. The obtained results indicate the presence of circulating monocytes with mitochondrial dysfunction and the association of such cells with chronic inflammation and atherosclerosis development.


Sign in / Sign up

Export Citation Format

Share Document