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Ernstsen Todd posted an update 5 days, 9 hours ago
Extracellular vesicles (EVs) are involved in intercellular communication during cancer progression; thus, elucidating the mechanism of EV secretion in cancer cells will contribute to the development of an EV-targeted cancer treatment. However, the biogenesis of EVs in cancer cells is not fully understood. MicroRNAs (miRNAs) regulate a variety of biological phenomena; thus, miRNAs could regulate EV secretion. Here, we performed high-throughput miRNA-based screening to identify the regulators of EV secretion using an ExoScreen assay. By using this method, we identified miR-26a involved in EV secretion from prostate cancer (PCa) cells. In addition, we found that SHC4, PFDN4, and CHORDC1 genes regulate EV secretion in PCa cells. Furthermore, the progression of the PCa cells suppressing these genes was inhibited in an in vivo study. Together, our findings suggest that miR-26a regulates EV secretion via targeting SHC4, PFDN4, and CHORDC1 in PCa cells, resulting in the suppression of PCa progression.The delivery of systemically administered gene therapies to brain tumors is exceptionally difficult because of the blood-brain barrier (BBB) and blood-tumor barrier (BTB). In addition, the adhesive and nanoporous tumor extracellular matrix hinders therapeutic dispersion. We first developed the use of magnetic resonance image (MRI)-guided focused ultrasound (FUS) and microbubbles as a platform approach for transfecting brain tumors by targeting the delivery of systemically administered “brain-penetrating” nanoparticle (BPN) gene vectors across the BTB/BBB. Next, using an MRI-based transport analysis, we determined that after FUS-mediated BTB/BBB opening, mean interstitial flow velocity magnitude doubled, with “per voxel” flow directions changing by an average of ~70° to 80°. Last, we observed that FUS-mediated BTB/BBB opening increased the dispersion of directly injected BPNs through tumor tissue by >100%. We conclude that FUS-mediated BTB/BBB opening yields markedly augmented interstitial tumor flow that, in turn, plays a critical role in enhancing BPN transport through tumor tissue.One of the major challenges limiting the efficacy of anti-PD-1/PD-L1 therapy in nonresponding patients is the failure of T cells to penetrate the tumor microenvironment. We showed that genetic or pharmacological inhibition of Vps34 kinase activity using SB02024 or SAR405 (Vps34i) decreased the tumor growth and improved mice survival in multiple tumor models by inducing an infiltration of NK, CD8+, and CD4+ T effector cells in melanoma and CRC tumors. Such infiltration resulted in the establishment of a T cell-inflamed tumor microenvironment, characterized by the up-regulation of pro-inflammatory chemokines and cytokines, CCL5, CXCL10, and IFNγ. Vps34i treatment induced STAT1 and IRF7, involved in the up-regulation of CCL5 and CXCL10. Combining Vps34i improved the therapeutic benefit of anti-PD-L1/PD-1 in melanoma and CRC and prolonged mice survival. Our study revealed that targeting Vps34 turns cold into hot inflamed tumors, thus enhancing the efficacy of anti-PD-L1/PD-1 blockade.Metal-organic frameworks (MOFs) have been attracting intensive attention because of their commendable potential in many applications. Postsynthetic modification for redesigning chemical characteristics and pore structures can greatly improve performance and expand functionality of MOF materials. Here, we develop a versatile vapor-phase linker exchange (VPLE) methodology for MOF modification. Through solvent-free and environment-friendly VPLE processing, various linker analogs with functional groups but not for straightforward MOF crystallization are inserted into frameworks as daughter building blocks. Besides single exchange for preparing MOFs with dual linkers, VPLE can further be performed by multistage operations to obtain MOF materials with multiple linkers and functional groups. The halogen-incorporated ZIFs exhibit good porosity, tunable molecular affinity, and impressive CO2/N2 and CH4/N2 adsorption selectivities up to 31.1 and 10.8, respectively, which are two to six times higher than those of conventional adsorbents. Moreover, VPLE can substantially enhance the compatibility of MOFs and polymers.The rapid development of treatment resistance in tumors poses a technological bottleneck in clinical oncology. Ferroptosis is a form of regulated cell death with clinical translational potential, but the efficacy of ferroptosis-inducing agents is susceptible to many endogenous factors when administered alone, for which some cooperating mechanisms are urgently required. Here, we report an amorphous calcium carbonate (ACC)-based nanoassembly for tumor-targeted ferroptosis therapy, in which the totally degradable ACC substrate could synergize with the therapeutic interaction between doxorubicin (DOX) and Fe2+. The nanoplatform was simultaneously modified by dendrimers with metalloproteinase-2 (MMP-2)-sheddable PEG or targeting ligands, which offers the functional balance between circulation longevity and tumor-specific uptake. The therapeutic cargo could be released intracellularly in a self-regulated manner through acidity-triggered degradation of ACC, where DOX could amplify the ferroptosis effects of Fe2+ by producing H2O2. This nanoformulation has demonstrated potent ferroptosis efficacy and may offer clinical promise.Poleward transport of warm Circumpolar Deep Water (CDW) has been linked to melting of Antarctic ice shelves. click here However, even the steady-state spatial distribution and mechanisms of CDW transport remain poorly understood. Using a global, eddying ocean model, we explore the relationship between the cross-slope transports of CDW and descending Dense Shelf Water (DSW). We find large spatial variability in CDW heat and volume transport around Antarctica, with substantially enhanced flow where DSW descends in canyons. The CDW and DSW transports are highly spatially correlated within ~20 km and temporally correlated on subdaily time scales. Focusing on the Ross Sea, we show that the relationship is driven by pulses of overflowing DSW lowering sea surface height, leading to net onshore CDW transport. The majority of simulated onshore CDW transport is concentrated in cold-water regions, rather than warm-water regions, with potential implications for ice-ocean interactions and global sea level rise.