PMC0
10.1021%2Fnn502807n
results and discussion
Previous reports indicate that nanoparticle treatment can induce the activation of endolysosomal vesicles after cellular uptake.>>33<<−35 This phenomenon was investigated with a Neutral Red assay (Supporting Information Figure S4), a test used to determine the modulation of endolysosomal activity by measuring the incorporation and retention of the Neutral Red dye within
Previous reports indicate that nanoparticle treatment can induce the activation of endolysosomal vesicles after cellular uptake.33−>>35<< This phenomenon was investigated with a Neutral Red assay (Supporting Information Figure S4), a test used to determine the modulation of endolysosomal activity by measuring the incorporation and retention of the Neutral Red dye within
with a Neutral Red assay (Supporting Information Figure S4), a test used to determine the modulation of endolysosomal activity by measuring the incorporation and retention of the Neutral Red dye within acidic intracellular vesicles.36,>>37<< MSN and Br–MSN increased Neutral Red uptake at all the tested doses in HUVEC, though the effect was not as pronounced for pure Bromelain treatment.
These data suggest that particle internalization in HUVEC increased autophagocytosis, verifying the results of the Neutral Red assay and other reports.>>33<<
These data suggest that particle internalization in HUVEC increased autophagocytosis, verifying the results of the Neutral Red assay and other reports.33,>>35<<
As previously reported in studies performed to evaluate Bromelain activity,>>38<< the proteolytic activity of Br–MSN was affected by decreasing the pH (Figure 4d), increasing the FBS concentration (Figure 4e) in the incubation solution, or decreasing the temperature (Figure 4f).
To further analyze the effect of Br–MSN on tumor ECM, we utilized the endothelial capillary network formation assay.>>39<< Matrigel’s ability to induce endothelial cells to form capillary-like structures is well documented.
conclusion
Tumor ECM significantly impairs the diffusion of the chemotherapeutics>>41<< impeding the adequate treatment of cancer cells that reside distantly from the blood vessels.
Tumor ECM significantly impairs the diffusion of the chemotherapeutics41 impeding the adequate treatment of cancer cells that reside distantly from the blood vessels.>>42<< These limitations become even more pronounced when macromolecules8,43,44 or nanoparticles10,12 are used as therapeutics or delivery platforms.
42 These limitations become even more pronounced when macromolecules>>8<<,43,44 or nanoparticles10,12 are used as therapeutics or delivery platforms.
42 These limitations become even more pronounced when macromolecules8,>>43<<,44 or nanoparticles10,12 are used as therapeutics or delivery platforms.
42 These limitations become even more pronounced when macromolecules8,43,>>44<< or nanoparticles10,12 are used as therapeutics or delivery platforms.
42 These limitations become even more pronounced when macromolecules8,43,44 or nanoparticles>>10<<,12 are used as therapeutics or delivery platforms.
42 These limitations become even more pronounced when macromolecules8,43,44 or nanoparticles10,>>12<< are used as therapeutics or delivery platforms.
systems designed to deeply penetrate the ECM are sensitive to the action of tumor extracellular metalloproteases that digest the deliverable’s structure, favoring their diffusion in the interstitial space and the release of their payload.>>2<<,45,46 On the other hand, an active approach designed to digest the tumor ECM by imparting carriers with hydrolytic activity could provide significant advantages for the delivery of therapeutics that must be protected during their route to
designed to deeply penetrate the ECM are sensitive to the action of tumor extracellular metalloproteases that digest the deliverable’s structure, favoring their diffusion in the interstitial space and the release of their payload.2,>>45<<,46 On the other hand, an active approach designed to digest the tumor ECM by imparting carriers with hydrolytic activity could provide significant advantages for the delivery of therapeutics that must be protected during their route to
designed to deeply penetrate the ECM are sensitive to the action of tumor extracellular metalloproteases that digest the deliverable’s structure, favoring their diffusion in the interstitial space and the release of their payload.2,45,>>46<< On the other hand, an active approach designed to digest the tumor ECM by imparting carriers with hydrolytic activity could provide significant advantages for the delivery of therapeutics that must be protected during their route to the
Superior diffusion within the tumor parenchyma is also essential for therapeutics designed for thermal ablation>>7<< whose efficiency depends on their homogeneous distribution throughout the tumor volume.
the surface of a model nanotherapeutic (i.e., MSN) with Bromelain to enhance their diffusion features upon contact with tumor ECM. Bromelain is an enzymatic complex extracted from pineapples, currently used for clinical purposes.17,>>18<<,24−26 The addition of the proteolytic activity onto the surface of MSN was achieved by covalent attachment of the enzymatic complex using well established bioconjugation techniques.
a greater extent within 1 h than nonproteolytic MSN. Like most hydrolytic enzymes, the activity of Bromelain was hindered by environmental conditions, such as low pH, increased concentration of serum proteins, and decreased temperatures.>>38<< Thus, future endeavors aimed at developing therapeutic strategies based on this approach must implement features to enhance the circulation time and protect Bromelain surface modification during circulation.
Recent studies have demonstrated the use of controlled proteolytic activity on tumor parenchyma as a successful strategy to increase therapeutic efficacy of macromolecules,>>8<<,9,11 as it favors the efficient diffusion of the treatment within the tumor parenchyma.
Recent studies have demonstrated the use of controlled proteolytic activity on tumor parenchyma as a successful strategy to increase therapeutic efficacy of macromolecules,8,>>9<<,11 as it favors the efficient diffusion of the treatment within the tumor parenchyma.
Recent studies have demonstrated the use of controlled proteolytic activity on tumor parenchyma as a successful strategy to increase therapeutic efficacy of macromolecules,8,9,>>11<< as it favors the efficient diffusion of the treatment within the tumor parenchyma.
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