The aim of this study was to prepare and evaluate α-mangostin-loaded polymeric nanoparticle gel (α-MNG-PLGA) formulation to enhance α-mangostin delivery in an epidermal carcinoma. The poly (D, L-lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) were developed using the emulsion-diffusion-evaporation technique with a 3-level 3-factor Box-Behnken design. The NPs were characterized and evaluated for particle size distribution, zeta potential (mV), drug release, and skin permeation. The formulated PLGA NPs were converted into a preformed carbopol gel base and were further evaluated for texture analysis, the cytotoxic effect of PLGA NPs against B16-F10 melanoma cells, and in vitro radical scavenging activity. The nanoscale particles were spherical, consistent, and average in size (168.06 ± 17.02 nm), with an entrapment efficiency (EE) of 84.26 ± 8.23% and a zeta potential of -25.3 ± 7.1 mV. Their drug release percentages in phosphate-buffered solution (PBS) at pH 7.4 and pH 6.5 were 87.07 ± 6.95% and 89.50 ± 9.50%, respectively. The release of α-MNG from NPs in vitro demonstrated that the biphasic release system, namely, immediate release in the initial phase, was accompanied by sustained drug release. The texture study of the developed α-MNG-PLGA NPs gel revealed its characteristics, including viscosity, hardness, consistency, and cohesiveness. The drug flux from α-MNG-PLGA NPs gel and α-MNG gel was 79.32 ± 7.91 and 16.88 ± 7.18 µg/cm2/h in 24 h, respectively. The confocal study showed that α-MNG-PLGA NPs penetrated up to 230.02 µm deep into the skin layer compared to 15.21 µm by dye solution. MTT assay and radical scavenging potential indicated that α-MNG-PLGA NPs gel had a significant cytotoxic effect and antioxidant effect compared to α-MNG gel (p < 0.05). Thus, using the developed α-MNG-PLGA in treating skin cancer could be a promising approach.
Cell-penetrating peptides (CPPs) are highly promising tools to deliver therapeutic molecules into tumours. αVβ3 integrins are cell-matrix adhesion receptors, and are considered as an attractive target for anticancer therapies owing to their roles in the process of metastasis and angiogenesis. Therefore, this study aims to assess the effect of co-administration of zerumbone (ZER) and ZERencapsulated in hydroxypropyl-β-cyclodextrin with TP5-iRGD peptide towards cell cytotoxicity, apoptosis induction, and proliferation of normal and cancerous breast cells utilizing in vitro assays, as well as to study the molecular docking of ZER in complex with TP5-iRGD peptide. Cell viability assay findings indicated that ZER and ZERencapsulated in hydroxypropyl-β-cyclodextrin (ZER-HPβCD) inhibited the growth of estrogen receptor positivebreast cancer cells (ER+ MCF-7) at 72 h treatment with an inhibitory concentration (IC)50 of 7.51 ± 0.2 and 5.08 ± 0.2 µg/mL, respectively, and inhibited the growth of triple negative breast cancer cells (MDA-MB-231) with an IC50 of 14.96 ± 1.52 µg/mL and 12.18 ± 0.7 µg/mL, respectively. On the other hand, TP5-iRGD peptide showed no significant cytotoxicity on both cancer and normal cells. Interestingly, co-administration of TP5-iRGD peptide in MCF-7 cells reduced the IC50 of ZER from 7.51 ± 0.2 µg/mL to 3.13 ± 0.7 µg/mL and reduced the IC50 of ZER-HPβCD from 5.08 ± 0.2 µg/mL to 0.49 ± 0.004 µg/mL, indicating that the co-administration enhances the potency and increases the efficacy of ZER and ZER-HPβCD compounds. Acridine orange (AO)/propidium iodide (PI) staining under fluorescence microscopy showed evidence of early apoptosis after 72 h from the co-administration of ZER or ZER-HPβCD with TP5-iRGD peptide in MCF-7 breast cancer cells. The findings of the computational modelling experiment provide novel insights into the ZER interaction with integrin αvβ3 in the presence of TP5-iRGD, and this could explain why ZER has better antitumor activities when co-administered with TP5-iRGD peptide.