Development of novel therapeutic strategies to eradicate malignant tumors is of paramount importance in cancer research. In a recent study, we have introduced a facile protocol for the preparation of corrole-protein nanoparticles (NPs). These NPs consist of a corrole-core coated with protein.
View Article and Find Full Text PDFTranscription factor EB (TFEB) is a master transcriptional regulator playing a key role in lysosomal biogenesis, autophagy and lysosomal exocytosis. TFEB activity is inhibited following its phosphorylation by mammalian target of rapamycin complex 1 (mTORC1) on the surface of the lysosome. Phosphorylated TFEB is bound by 14-3-3 proteins, resulting in its cytoplasmic retention in an inactive state.
View Article and Find Full Text PDFLysoTracker and MitoTracker Red are fluorescent probes widely used for viable cell staining of lysosomes and mitochondria, respectively. They are utilized to study organelle localization and their resident proteins, assess organelle functionality and quantification of organelle numbers. The ATP-driven efflux transporter P-glycoprotein (P-gp) is expressed in normal and malignant tissues and extrudes structurally distinct endogenous and exogenous cytotoxic compounds.
View Article and Find Full Text PDFWe have recently shown that hydrophobic weak base anticancer drugs are highly sequestered in acidic lysosomes, inducing TFEB-mediated lysosomal biogenesis and markedly increased lysosome numbers per cell. This enhanced lysosomal sequestration of chemotherapeutics, away from their intracellular targets, provoked cancer multidrug resistance. However, little is known regarding the fate of lysosome-sequestered drugs.
View Article and Find Full Text PDFDrug resistance remains a leading cause of chemotherapeutic treatment failure and cancer-related mortality. While some mechanisms of anticancer drug resistance have been well characterized, multiple mechanisms remain elusive. In this respect, passive ion trapping-based lysosomal sequestration of multiple hydrophobic weak-base chemotherapeutic agents was found to reduce the accessibility of these drugs to their target sites, resulting in a markedly reduced cytotoxic effect and drug resistance.
View Article and Find Full Text PDFMultidrug resistance (MDR) is a primary hindrance to curative cancer chemotherapy. In this respect, lysosomes were suggested to play a role in intrinsic MDR by sequestering protonated hydrophobic weak base chemotherapeutics away from their intracellular target sites. Here we show that intrinsic resistance to sunitinib, a hydrophobic weak base tyrosine kinase inhibitor known to accumulate in lysosomes, tightly correlates with the number of lysosomes accumulating high levels of sunitinib in multiple human carcinoma cells.
View Article and Find Full Text PDFTelomerase is a ribonucleoprotein reverse transcriptase that copies a short template within its integral telomerase RNA moiety (TER) onto eukaryotic chromosome ends, thus compensating for incomplete replication and degradation. The highly divergent yeast TER is structured in three long arms, with a catalytic core at its center. A binding site for the protein Ku80 is conserved within the 5' arm of TER in Saccharomyces but not in Kluyveromyces budding yeast species.
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