RESUMO
Combining sonochemistry with phytochemistry is a modern trend in the biosynthesis of metallic nanoparticles (NPs), which contributes to the sustainability of chemical processes and minimizes hazardous effects. Herein, titanium dioxide (TiO2) NPs were bioengineered using a novel and facile ultrasound-assisted approach utilizing the greenly extracted essential oil of Ocimum basilicum. FTIR and UV-Vis spectrophotometry were used to confirm the formation of TiO2 NPs. The X-ray diffraction (XRD) analysis showed the crystalline nature of TiO2 NPs. TEM analysis revealed the spherical morphology of the NPs with sizes ranging from 5.55 to 13.89 nm. Energy-dispersive X-ray (EDX) confirmed the purity of the greenly synthesized NPs. TiO2 NPs demonstrated outstanding antitumor activity against breast (MCF-7) and lung (A-549) cancer cells with estimated IC50 values of 1.73 and 4.79 µg mL-1. The TiO2 NPs were cytocompatible to normal cells (MCF-10A) with a selectivity index (SI) of 8.77 for breast and 3.17 for lung cancer. Biological assays revealed a promising potential for TiO2 NPs to induce apoptosis and arrest cells at the sub-G1 phase of the cell cycle phase in both cancer cell lines. Molecular investigations showed the ability of TiO2 NPs to increase apoptotic genes' expression (Bak and Bax) and their profound ability to elevate the expression of apoptotic proteins (caspases 3 and 7). Molecular docking demonstrated strong binding interactions for TiO2 NPs with caspase 3 and EGFR-TK targets. In conclusion, the greenly synthesized TiO2 NPs exhibited potent antitumor activity and mitochondrion-based cell death against breast and lung cancer cell lines while maintaining cytocompatibility against normal cells.
RESUMO
Currently, the main pillars in treating breast cancer involve tumorectomy pursued by hormonal, radio, or chemotherapies. Nonetheless, these approaches exhibit severe adverse effects and might suffer from tumor recurrence. Therefore, there is a considerable demand to fabricate an innovative controlled-release nano-delivery system to be implanted after tumor surgical removal to guard against cancer recurrence. In addition, combining platinum-based drugs with phytochemicals is a promising approach to improving the anticancer activity of the chemotherapeutics against tumor cells while minimizing their systemic effects. This study designed polycaprolactone (PCL)-based electrospun nanofiber mats encapsulating nedaplatin (N) and Peganum harmala alkaloid-rich fraction (L). In addition to physicochemical characterization, including average diameters, morphological features, degradation study, thermal stability, and release kinetics study, the formulated nanofibers were assessed in terms of cytotoxicity, where they demonstrated potentiated effects and higher selectivity towards breast cancer cells. The dual-loaded nanofiber mats (N + L@PCL) demonstrated the highest antiproliferative effects against MCF-7 cells with a recorded IC50 of 3.21 µg/mL, as well as the topmost achieved selectivity index (20.45) towards cancer cells amongst all the tested agents (N, L, N@PCL, and L@PCL). This indicates that the dual-loaded nanofiber excelled at conserving the normal breast epithelial cells (MCF-10A). The combined therapy, N + L@PCL treatment, resulted in a significantly higher percent cell population in the late apoptosis and necrosis quartiles as compared to all other treatment groups (p-value of ≤0.001). Moreover, this study of cell cycle kinetics revealed potentiated effects of the dual-loaded nanofiber (N + L@PCL) at trapping more than 90% of cells in the sub-G1 phase and reducing the number of cells undergoing DNA synthesis in the S-phase by 15-fold as compared to nontreated cells; hence, causing cessation of the cell cycle and confirming the apoptosis assay results. As such, our findings suggest the potential use of the designed nanofiber mats as perfect implants to prevent tumor recurrence after tumorectomy.
RESUMO
Smart pH-responsive niosomes loaded with either Oxaliplatin (Ox), Ylang ylang essential oil (Y-oil), or co-loaded with both compounds (Ox-Y) (Ox@NSs, Y@NSs, and Ox-Y@NSs, respectively) were formulated utilizing the thin film method. The developed nanocontainers had a spherical morphology with mean particle sizes lower than 170 nm and showed negative surface charges, high entrapment efficiencies, and a pH-dependent release over 24 h. The prepared pH-responsive niosomes' cytotoxicity was tested against the invasive triple-negative breast cancer (MDA-MB-231) cells, compared to free OX and Y-oil. All niosomal formulations loaded with Ox and/or Y-oil significantly improved cytotoxic activity relative to their free counterparts. The Ox-Y@NSs demonstrated the lowest IC50 (0.0002 µg/mL) when compared to Ox@NSs (0.006 µg/mL) and Y@NSs (18.39 µg/mL) or unloaded Ox (0.05 µg/mL) and Y-oil (29.01 µg/mL). In addition, the percentages of the MDA-MB-231 cell population in the late apoptotic and necrotic quartiles were profoundly higher in cells treated with the smart Ox-Y@NSs (8.38% and 5.06%) than those exposed to free Ox (7.33% and 1.93%) or Y-oil (2.3% and 2.13%) treatments. Gene expression analysis and protein assays were performed to provide extra elucidation regarding the molecular mechanism by which the prepared pH-sensitive niosomes induce apoptosis. Ox-Y@NSs significantly induced the gene expression of the apoptotic markers Tp53, Bax, and Caspase-7, while downregulating the antiapoptotic Bcl2. As such, Ox-Y@NSs are shown to activate the intrinsic pathway of apoptosis. Moreover, the protein assay ascertained the apoptotic effects of Ox-Y@NSs, generating a 4-fold increase in the relative protein quantity of the late apoptotic marker Caspase-7. Our findings suggest that combining natural essential oil with synthetic platinum-based drugs in pH-responsive nanovesicles is a promising approach to breast cancer therapy.
