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Delikatny, E. J.

Publications and source records attributed to Delikatny, E. J..

2 recordsLinked to original sources

Inhibition of glioblastoma cell proliferation and invasion by the choline-kinase inhibitor JAS239 varies with cell type and hypoxia

BackgroundElevated choline kinase alpha (ChoK) is observed in most solid tumours including glioblastomas (GBM), yet until recently, inhibitors of ChoK have demonstrated limited efficacy in GBM models. Given that hypoxia is associated with GBM therapy resistance, we hypothesised that tumour hypoxia could be responsible for such limitations. We therefore evaluated in GBM cells, the effect of hypoxia on the function of JAS239, a potent ChoK inhibitor. MethodsRodent (F98 and 9L) and human (U-87 MG and U-251 MG) GBM cell lines were subjected to 72 hours of hypoxia conditioning and treated with JAS239 for 24 hours. NMR metabolomic measurements and analyses were performed to evaluate the signalling pathways involved. In addition, cell proliferation, cell cycle progression and cell invasion were measured in cell monolayers and 3D spheroids, with or without JAS239 treatment in normoxic or hypoxic cells to assess how hypoxia affects JAS239 function. ResultsHypoxia and JAS239 treatment led to significant changes in the cellular metabolic pathways, specifically the phospholipid and glycolytic pathways associated with a reduction in cell proliferation via induced cell cycle arrest. Interestingly, JAS239 also impaired GBM invasion. However, JAS239 effects were variable depending on the cell line, reflecting the inherent heterogeneity observed in GBMs. ConclusionOur findings indicate that JAS239 and hypoxia can deregulate cellular metabolism, inhibit proliferation and alter cell invasion. These results may be useful for the design of new therapeutic strategies based on ChoK inhibition that can act on multiple pro-tumorigenic features.

cancer biology↗

A biodegradable "one-for-all" nanoparticle for multimodality imaging and enhanced photothermal treatment of breast cancer

Silver sulfide nanoparticles (Ag2S-NP) have been proposed for various optical-based biomedical applications, such as near-infrared fluorescence (NIRF) imaging, photoacoustics (PA) and photothermal therapy (PTT). However, their absorbance is relatively low in the NIR window used in these applications, and previous formulations were synthesized using toxic precursors under harsh conditions and have clearance issues due to their large size. Herein, we synthesized sub-5 nm Ag2S-NP and encapsulated them in biodegradable, polymeric nanoparticles (AgPCPP). All syntheses were conducted using biocompatible reagents in the aqueous phase and under ambient conditions. We found that the encapsulation of Ag2S-NP in polymeric nanospheres greatly increases their NIR absorbance, resulting in enhanced optical imaging and photothermal heating effects. We therefore found that AgPCPP have potent contrast properties for PA and NIRF imaging, as well as for computed tomography (CT). We demonstrated the applicability of AgPCPP nanoparticles as a multimodal imaging probe that readily improves the conspicuity of breast tumors in vivo. PTT was performed using AgPCPP with NIR laser irradiation, which led to significant reduction in breast tumor growth and prolonged survival compared to free Ag2S-NP. Lastly, we observed a gradual decrease in AgPCPP retention in tissues over time with no signs of acute toxicity, thus providing strong evidence of safety and biodegradability. Therefore, AgPCPP may serve as a "one-for-all" theranostic agent that degrades into small components for excretion once the diagnostic and therapeutic tasks are fulfilled, thus providing good prospects for translation to clinical use. TOC graphic O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=119 SRC="FIGDIR/small/568885v1_ufig1.gif" ALT="Figure 1"> View larger version (28K): org.highwire.dtl.DTLVardef@e6be5dorg.highwire.dtl.DTLVardef@dbce2eorg.highwire.dtl.DTLVardef@bd5360org.highwire.dtl.DTLVardef@1acf01d_HPS_FORMAT_FIGEXP M_FIG C_FIG

bioengineering↗