scholarly journals Sulfasalazine Sensitizes Polyhematoporphyrin-Mediated Photodynamic Therapy in Cholangiocarcinoma by Targeting xCT

2021 ◽  
Vol 12 ◽  
Author(s):  
Yan-Wen Zheng ◽  
Xiong-Ying Miao ◽  
Li Xiong ◽  
Bo Chen ◽  
Fan-Hua Kong ◽  
...  
Keyword(s):  
Photodynamic Therapy ◽  
Cell Viability ◽  
Poor Prognosis ◽  
Therapeutic Option ◽  
Acid Transport ◽  
Antioxidant Defence ◽  
Amino Acid Transport System ◽  
Inflammatory Agent ◽  
Intracellular Glutathione ◽  
Dependent Mechanism

Cholangiocarcinoma (CCA), which is highly malignant, shows a relatively poor prognosis, due to the insensitivity of the tumour to chemotherapy and radiotherapy. Photodynamic therapy (PDT) has become a promising palliative therapeutic option for patients with unresectable cholangiocarcinoma (CCA), while the functional amount of ROS is limited by intracellular redox systemen. Sulfasalazine (SASP), a well-known anti-inflammatory agent, which also acts as an inhibitor of the amino acid transport system xc (xCT), decreases the intracellular glutathione (GSH) level, thus weakening the antioxidant defence of the cell by inhibition of the antiporter. However, the combination of SASP and PDT remains unexplored. We have reported that polyhematoporphyrin (PHP)-mediated PDT inhibits the cell viability of CCA cells and organoids. Furthermore, in PHP-enriched HCCC-9810 and TFK-1CCA cells, SASP enhances the sensitivity to PHP-mediated PDT through a GSH-dependent mechanism. We found that PHP-PDT can up-regulate xCT expression to promote cells against overloaded ROS, while SASP reduces GSH levels. After the combination of SASP and PHP-PDT, cell viability and GSH levels were significantly inhibited. xCT was also observed to be inhibited by SASP in human organoid samples. Our findings suggest that, in combination with PDT, SASP has potential as a promising approach against CCA.

MiR-485-5p Promotes Neuron Survival through Mediating Rac1/Notch2 Signaling Pathway after Cerebral Ischemia/Reperfusion

2020 ◽  
Vol 17 (3) ◽  
pp. 259-266 ◽  
Author(s):  
Xuan Chen ◽  
Sumei Zhang ◽  
Peipei Shi ◽  
Yangli Su ◽  
Dong Zhang ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Cell Viability ◽  
Therapeutic Option ◽  
Ischemia Reperfusion ◽  
Glucose Deprivation ◽  
Small Gtpase ◽  
Luciferase Reporter ◽  
Pathological Feature ◽  
In Cells

Objective: Ischemia-reperfusion (I/R) injury is a pathological feature of ischemic stroke. This study investigated the regulatory role of miR-485-5p in I/R injury. Methods: SH-SY5Y cells were induced with oxygen and glucose deprivation/reoxygenation (OGD/R) to mimic I/R injury in vitro. Cells were transfected with designated constructs (miR-485- 5p mimics, miR-485-5p inhibitor, lentiviral vectors overexpressing Rac1 or their corresponding controls). Cell viability was evaluated using the MTT assay. The concentrations of lactate dehydrogenase, malondialdehyde, and reactive oxygen species were detected to indicate the degree of oxidative stress. Flow cytometry and caspase-3 activity assay were used for apoptosis assessment. Dual-luciferase reporter assay was performed to confirm that Rac family small GTPase 1 (Rac1) was a downstream gene of miR-485-5p. Results: OGD/R resulted in decreased cell viability, elevated oxidative stress, increased apoptosis, and downregulated miR-485-5p expression in SH-SY5Y cells. MiR-485-5p upregulation alleviated I/R injury, evidenced by improved cell viability, decreased oxidative markers, and reduced apoptotic rate. OGD/R increased the levels of Rac1 and neurogenic locus notch homolog protein 2 (Notch2) signaling-related proteins in cells with normal miR-485-5p expression, whereas miR- 485-5p overexpression successfully suppressed OGD/R-induced upregulation of these proteins. Furthermore, the delivery of vectors overexpressing Rac1 in miR-485-5p mimics-transfected cells reversed the protective effect of miR-485-5p in cells with OGD/R-induced injury. Conclusion: This study showed that miR-485-5p protected cells following I/R injury via targeting Rac1/Notch2 signaling suggest that targeted upregulation of miR-485-5p might be a promising therapeutic option for the protection against I/R injury.

scholarly journals Reaction between Graphene Oxide and Intracellular Glutathione Affects Cell Viability and Proliferation

2021 ◽  
Vol 13 (3) ◽  
pp. 3528-3535
Author(s):  
Baojin Ma ◽  
Shi Guo ◽  
Yuta Nishina ◽  
Alberto Bianco
Keyword(s):  
Graphene Oxide ◽  
Cell Viability ◽  
Intracellular Glutathione

The vacuolar amino acid transport system is a novel, direct target of GATA transcription factors

2021 ◽  
Vol 85 (3) ◽  
pp. 587-599
Author(s):  
Akane Sato ◽  
Takumi Kimura ◽  
Kana Hondo ◽  
Miyuki Kawano-Kawada ◽  
Takayuki Sekito
Keyword(s):  
Transcription Factors ◽  
Amino Acid ◽  
Amino Acid Transport ◽  
Amino Acid Transporters ◽  
Acid Transport ◽  
Amino Acid Transport System ◽  
Gata Transcription Factor ◽  
Gata Transcription Factors ◽  
Acid Status ◽  
Direct Target

ABSTRACT In Saccharomyces cerevisiae, Avt4 exports neutral and basic amino acids from vacuoles. Previous studies have suggested that the GATA transcription factors, Gln3 and Gat1, which are key regulators that adapt cells in response to changes in amino acid status, are involved in the AVT4 transcription. Here, we show that mutations in the putative GATA-binding sites of the AVT4 promoter reduced AVT4 expression. Consistently, a chromatin immunoprecipitation (ChIP) assay revealed that Gat1-Myc13 binds to the AVT4 promoter. Previous microarray results were confirmed that gln3∆gat1∆ cells showed a decrease in expression of AVT1 and AVT7, which also encode vacuolar amino acid transporters. Additionally, ChIP analysis revealed that the AVT6 encoding vacuolar acidic amino acid exporter represents a new direct target of the GATA transcription factor. The broad effect of the GATA transcription factors on the expression of AVT transporters suggests that vacuolar amino acid transport is integrated into cellular amino acid homeostasis.

Osmotic Regulation of ATA2 mRNA Expression and Amino Acid Transport System A Activity

2001 ◽  
Vol 283 (1) ◽  
pp. 174-178 ◽  
Author(s):  
Roberta R. Alfieri ◽  
Pier-Giorgio Petronini ◽  
Mara A. Bonelli ◽  
Alessandro E. Caccamo ◽  
Andrea Cavazzoni ◽  
...  
Keyword(s):  
Amino Acid ◽  
Mrna Expression ◽  
Transport System ◽  
Amino Acid Transport ◽  
Osmotic Regulation ◽  
Acid Transport ◽  
Amino Acid Transport System ◽  
System A

scholarly journals Chemosensitizing effect of maitake mushroom extract on carmustine cytotoxicity in human bladder cancer cells

2020 ◽  
Vol 8 (9) ◽  
pp. 3154
Author(s):  
Joel Hillelsohn ◽  
Michael Stern ◽  
Mina Iskander ◽  
Muhammad Choudhury ◽  
Sensuke Konno
Keyword(s):  
Oxidative Stress ◽  
Bladder Cancer ◽  
Cell Viability ◽  
Cancer Cells ◽  
Anticancer Drugs ◽  
Therapeutic Option ◽  
Human Bladder Cancer ◽  
Human Bladder ◽  
Mushroom Extract ◽  
T24 Cells

Background: Despite several therapeutic options available for bladder cancer, the outcomes are less satisfactory.  To find a more effective modality, we were interested in the bioactive mushroom extract, PDF, which has been shown to sensitize certain anticancer drugs.  Accordingly, we investigated if cytotoxic effects of several anticancer drugs used on bladder cancer patients could be enhanced with PDF in vitro.Methods: Human bladder cancer T24 cells were treated with four anticancer drugs, carmustine (BCNU), 5-fluorouracil (5FU), cisplatin (CPL), and doxorubicin (DOX) alone, their combinations, or in combination with PDF, and cell viability was determined.  To explore the anticancer mechanism, the status of glyoxalase I (Gly-I), an enzyme involved in the drug resistance of cancer cells, and oxidative stress that can cause severe cellular injury/damage was also assessed.Results: BCNU and 5FU alone resulted in a >50% reduction in cell viability but CPL and DOX had no such effects.  Only a combination of BCNU and PDF led to a drastic (~90%) cell viability reduction, accompanied by inactivation of Gly-I and an increase in oxidative stress.  However, any combinations of other drugs and PDF had little effects on cell viability, Gly-I activity, or severity of oxidative stress.Conclusions: This study shows that anticancer activity of BCNU is significantly potentiated with PDF in T24 cells.  This is rather attributed to inactivated Gly-I and increased oxidative stress.  Therefore, PDF appears to have a chemosensitizing effect capable of enhancing BCNU cytotoxicity, which may offer an alternative, improved therapeutic option for bladder cancer.

Design of a graphene oxide-BODIPY conjugate for glutathione depletion and photodynamic therapy

2D Materials ◽  
2021 ◽  
Author(s):  
Giacomo Reina ◽  
Amalia Ruiz ◽  
Barbara Richichi ◽  
Giacomo Biagiotti ◽  
Gina Elena Giacomoazzo ◽  
...  
Keyword(s):  
Graphene Oxide ◽  
Photodynamic Therapy ◽  
Cell Viability ◽  
Catalytic Mechanism ◽  
Glutathione Transferase ◽  
Bathochromic Shift ◽  
3D Models ◽  
Glutathione Depletion ◽  
In Vitro Biocompatibility

Abstract Boron dipyrromethene derivates (BODIPYs) are promising photosensitisers (PSs) for cancer treatment using photodynamic therapy (PDT). This study investigates the functionalisation of graphene oxide (GO) with a BODIPY derivate for glutathione (GSH) depletion and PDT. The functionalisation of GO with a 3,5-dichloro-8-(4-boronophenyl) BODIPY via a diol derivatisation with the phenyl boronic acid moiety at the meso position of the BODIPY core, allowed to preserve the intrinsic properties of GO. We demonstrated that both chlorine atoms were substituted by GSH in the presence of glutathione transferase (GST), inducing a relevant bathochromic shift in the absorption/emission features and thus generating the active PS. Ex vitro assessment using cell lysates containing cytoplasmatic GST revealed the intracellular catalytic mechanism for the nucleophilic substitution of the GO-BODIPY adduct with GSH. Confocal microscopy studies showed important differences in the cellular uptake of free BODIPY and GO-BODIPY and revealed the coexistence of GO-BODIPY, GO-BODIPY-GS, and GO-BODIPY-GS2 species inside vesicles and in the cytoplasm of the cells after 24 h of incubation. In vitro biocompatibility and safety of GO and GO-BODIPY were evaluated in 2D and 3D models of prostate adenocarcinoma cells (PC-3), where no toxicity was observed up to 100 µg/mL of GO/GO-BODIPY in all treated groups 24 h post-treatment (cell viability > 90%). Only a slight decrease to 80% at 100 µg/mL was observed after 48 h of incubation. We demonstrated the efficacy of a GO adduct containing an α-chlorine-substituted BODIPY for the simultaneous depletion of intracellular GSH and the photogeneration of reactive oxygen species using a halogen white light source (5.4 mW/cm2) with a maximum in the range of 500-800 nm, which significantly reduced cell viability (< 50%) after irradiation. Our study provides a new vision on how to apply BODIPY derivates and potentiate the toxicity of PDT in prostate and other types of cancer.

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