Graphene oxide nanoribbons/polypyrrole nanocomposite film: Controlled release of leucovorin by electrical stimulation

EGFR-targeting polydopamine nanoparticles co-loaded with 5-fluorouracil, irinotecan, and leucovorin to potentially enhance metastatic colorectal cancer therapy

Despite all prevention programs, many cases of colorectal cancer (CRC) are diagnosed when they have already metastasized. Herein, chemotherapy is required, and combination of 5-fluorouracil, irinotecan, and leucovorin (FOLFIRI) is one of the first-line treatments chosen. However, it is so toxic that compromises patient outcomes. Thus, with the aim of improving FOLFIRI pharmacokinetics while reducing its side effects, the three compounds that make it up were simultaneously absorbed in this work into polydopamine nanoparticles (PDA NPs), also loaded with an antibody to target CRC cells overexpressing the epithermal growth factor receptor (EGFR). All adsorptions, which were successfully executed without toxic solvents, were electrostatic in nature according to the calorimetry results obtained. Otherwise, based on the experiments done, 5-flurouracil, irinotecan, and leucovorin release from PDA NPs followed a burst-like pattern, which was possibly mediated by Fickian diffusion mechanisms. Finally, the assays performed with two EGFR-overexpressing CRC cell lines showed that the uptake of the nanosystem was rapid, and that its therapeutic effect was very significant. It managed to greatly reduce the viability of these cells to 22-30% after 72 h of incubation. Furthermore, when tumor spheroids were developed and treated with PDA NPs loaded with FOLFIRI and the anti-EGFR antibody (FOLFIRI-CTX@PDA NPs), these demonstrated to continue to have very marked therapeutic activity. In addition, FOLFIRI-CTX@PDA NPs affected to a lesser extent the survival rate of stromal cells, with which viability experiments were also done. Therefore, the novel developed PDA nanocarrier could be a promising strategy to enhance metastatic CRC therapy hereafter.

Alginate-modified graphene oxide anchored with lactoperoxidase as a novel bioactive nanocombination for colorectal cancer therapy

It is imperative to explore new biocompatible drugs with low toxicity for use in medicinal fields such as fighting tumors. Bovine lactoperoxidase (BLPO) stems from the most important enzymes in the bovine whey that provide a proper pattern for nano-formulation with nanomaterials. LPO is a suitable protein to be coated or adsorbed to alginate modified graphene oxide (GO-SA), which forms the modified GO-SA-LPO hybrid structure. This novel combination provides LPO stability with strong anticancer effects and boosts immunity response. The characterization results obtained from different techniques confirmed a successful LPO adsorption on the GO-SA composite surface. Moreover, nano-formulation of LPO with GO-SA composite exhibited a reduction in its size and overall charge. In addition, the experimental results showed greater LPO activity stability in the modified GO-SA-LPO nanocombination than free LPO after storage for 10 weeks at 4 °C. The in vitro study, a crucial step in the validation of our approach, demonstrated that the modified GO-SA-LPO nanocombination showed a potent anticancer selectivity toward colon cancer cell lines more than GO-SA composite or free form of LPO, which enhanced in a dose-dependent manner with high safety manner against normal cells. The apoptotic effect of this novel nanocombination was confirmed by the greatest variations in the expression of both well-known apoptosis genes (p53 and Bcl-2), severe changes in the cellular morphology, DNA fragmentation, and nuclear staining with fluorescence yellow and orange of the target cancer cells. Also, this superior efficacy of the modified GO-SA-LPO nanocombination was induced by suppressing some pro-inflammatory cytokines, including tumor necrosis factor-alpha (TNF-α), interleukin (IL-6), and necrosis factor-kappa B (NF-ĸB). Our observations presented that the modified nanocombination of LPO may offer a novel remedy for treating colon tumors via induced apoptosis pathway, inflammation reduction, and immune response improvement.

Tumor tropic delivery of FU.FA@NSs using mesenchymal stem cells for synergistic chemo-photodynamic therapy of colorectal cancer

To overcome the limitations associated with the targeting abilities of nanotherapeutics and drug loading capacity of mesenchymal stem cells (MSCs), the present study relies on the combination of MSCs tumor tropism with the controlled release function of nano-based drug delivery platforms to achieve tumor-specific accumulation of chemotherapeutics with minimal off-target effects. 5-fluorouracil (5-FU)-containing ceria (CeNPs) coated calcium carbonate nanoparticles (CaNPs) were functionalized with folinic acid (FA) to develop drug-containing nanocomposites (Ca.FU.Ce.FA NCs). NCs were then conjugated with graphene oxide (GO) and decorated with silver nanoparticles (Ag°NPs) to form FU.FA@NS, a rationally designed drug delivery system with O₂ generation capacity that alleviates tumor hypoxia for improved photodynamic therapy. Engineering of MSCs with FU.FA@NSs provided successful loading and long-term retention of therapeutics on the surface membrane with minimal changes to the functional properties of MSCs. Co-culturing of FU.FA@NS.MSCs with CT26 cells upon UVA exposure revealed enhanced apoptosis in tumor cells through ROS-mediated mitochondrial pathway. FU.FA@NSs released from MSCs were effectively taken up by CT26 cells via a clathrin-mediated endocytosis pathway and distributed their drug depots in a pH, H₂O₂, and UVA-stimulated fashion. Therefore, the cell-based biomimetic drug delivery platform formulated in the current study could be considered a promising strategy for targeted chemo-photodynamic therapy of colorectal cancer.