16 research outputs found
Zileuton™ loaded in polymer micelles effectively reduce breast cancer circulating tumor cells and intratumoral cancer stem cells
Tumor recurrence, metastatic spread and progressive gain of chemo-resistance of advanced cancers are sustained by the presence of cancer stem cells (CSCs) within the tumor. Targeted therapies with the aim to eradicate these cells are thus highly regarded. However, often the use of new anti-cancer therapies is hampered by pharmacokinetic demands. Drug delivery through nanoparticles has great potential to increase efficacy and reduce toxicity and adverse effects. However, its production has to be based on intelligent design. Likewise, we developed polymeric nanoparticles loaded with Zileuton™, a potent inhibitor of cancer stem cells (CSCs), which was chosen based on high throughput screening. Its great potential for CSCs treatment was subsequently demonstrated in in vitro and in in vivo CSC fluorescent models. Encapsulated Zileuton™ reduces amount of CSCs within the tumor and effectively blocks the circulating tumor cells (CTCs) in the blood stream and metastatic spread
A new approach to obtain pure and active proteins from Lactococcus lactis protein aggregates
The production of pure and soluble proteins is a complex, protein-dependent and time-consuming
process, in particular for those prone-to-aggregate and/or difcult-to-purify. Although Escherichia coli is
widely used for protein production, recombinant products must be co-purifed through costly processes
to remove lipopolysaccharide (LPS) and minimize adverse efects in the target organism. Interestingly,
Lactococcus lactis, which does not contain LPS, could be a promising alternative for the production
of relevant proteins. However, to date, there is no universal strategy to produce and purify any
recombinant protein, being still a protein-specifc process. In this context and considering that L. lactis
is also able to form functional protein aggregates under overproduction conditions, we explored the use
of these aggregates as an alternative source of soluble proteins. In this study, we developed a widely
applicable and economically afordable protocol to extract functional proteins from these nanoclusters.
For that, two model proteins were used: mammary serum amyloid A3 (M-SAA3) and metalloproteinase
9 (MMP-9), a difcult-to-purify and a prone-to-aggregate protein, respectively. The results show that
it is possible to obtain highly pure, soluble, LPS-free and active recombinant proteins from L. lactis
aggregates through a cost-efective and simple protocol with special relevance for difcult-to-purify or
highly aggregated proteins.info:eu-repo/semantics/publishedVersio
Structural and functional features of self-assembling protein nanoparticles produced in endotoxin-free Escherichia coli
Kosovo The crisis and beyond
Available from British Library Document Supply Centre-DSC:f99/2238 / BLDSC - British Library Document Supply CentreSIGLEGBUnited Kingdo
Positive in vitro wound healing effects of functional inclusion bodies of a lipoxygenase from the Mexican axolotl
Dynamism, sensitivity, and consequences of mesenchymal and stem-like phenotype of cancer cells
There are remarkable similarities in the description of cancer stem cells (CSCs) and cancer cells with mesenchymal phenotype. Both cell types are highly tumorigenic, resistant against common anticancer treatment, and thought to cause metastatic growth. Moreover, cancer cells are able to switch between CSC and non-CSC phenotypes and vice versa, to ensure the necessary balance within the tumor. Likewise, cancer cells can switch between epithelial and mesenchymal phenotypes via well-described transition (EMT/MET) that is thought to be crucial for tumor propagation. In this review, we discuss whether, and to which extend, the CSCs and mesenchymal cancer cells are overlapping phenomena in terms of mechanisms, origin, and implication for cancer treatment. As well, we describe the dynamism of both phenotypes and involvement of the tumor microenvironment in CSC reversion and in EMT.This work was partially supported by grants PI14/02079 and PI17/02242 from Fondo de Investigaciones Sanitarias (FIS) of Instituto Carlos III (ISCIII), cofinanced by the European Regional Development Fund (FEDER), and grant AC15/00092 (Target4Cancer project) from EuroNanoMed II to SS and grant 337/C/2013 (PENTRI project) from Fundació Marató TV3 (Catalonia, Spain) to IA. The Portuguese Science and Technology Foundation (FCT) supported FA with a postdoctoral grant (SFRH/BD/76270/2011). La Asociación Española Contra el Cáncer (AECC) supported 8 Stem Cells International JSF with a postdoctoral fellowship. Plan Estratégico de Investigación e Innovación en Salud (PERIS) supported FM
A nanostructured bacterial bioscaffold for the sustained bottom-up delivery of protein drugs
Aims: Bacterial inclusion bodies (IBs) are protein-based, amyloidal nanomaterials that mechanically stimulate mammalian cell proliferation upon surface decoration. However, their biological performance as potentially functional scaffolds in mammalian cell culture still needs to be explored.<p></p>
Materials and methods: Using fluorescent proteins, we demonstrate significant membrane penetration of surface-attached IBs and a corresponding intracellular bioavailability of the protein material. Results: When IBs are formed by protein drugs, such as the intracellular acting human chaperone Hsp70 or the extracellular/intracellular acting human FGF-2, IB components intervene on top-growing cells, namely by rescuing them from chemically induced apoptosis or by stimulating cell division under serum starvation, respectively. Protein release from IBs seems to mechanistically mimic the sustained secretion of protein hormones from amyloid-like secretory granules in higher organisms.<p></p>
Conclusions: We propose bacterial IBs as biomimetic nanostructured scaffolds (bioscaffolds) suitable for tissue engineering that, while acting as adhesive materials, partially disintegrate for the slow release of their biologically active building blocks. The bottom-up delivery of protein drugs mediated by bioscaffolds offers a highly promising platform for emerging applications in regenerative medicine.<p></p>