Tipaporn Kumkoon

Mallotumide A (MA) is a novel cycloheptapeptide isolated from the roots of Mallotus spodocarpus Airy Shaw. It exerts anticancer activity by downregulating several lipogenic enzymes and cellular respiration, particularly in triple‐negative breast cancer. However, MA has poor water solubility and is highly toxic to both cancer and normal cells, limiting its therapeutic applications. To address these drawbacks, MA was encapsulated within poly(lactic‐co‐glycolic acid) (PLGA) nanoparticles (NPs) and coated with riboflavin (Rf)‐modified chitosan (CR), creating (MA)PLGA/CR NPs. This study characterized the NPs and investigated their encapsulation efficiency of MA, cellular uptake, and anticancer activity in two breast cancer (MDA‐MB‐231 and MCF‐7) and normal (MCF‐10A) cell lines. The NPs were spherical with an average size of 300 ± 6.64 nm and a zeta potential of +11.96 mV. The PLGA/CR NPs exhibited enhanced cellular uptake in both cancer cells in a dose‐ and time‐dependent manner, while reducing toxicity in normal cells. Furthermore, the (MA)PLGA/CR NPs inhibited the viability, migration, and invasion of MDA‐MB‐231 cells, thereby demonstrating their potential as a targeted anticancer delivery system.

Mango (Mangifera indica) has been one of the most cultivated fruits in Thailand and other South and Southeast Asian countries. ‘Bao’ mango is a distinct petite mango variety that is available all year round. This study aimed to investigate the antioxidant and anti‐breast cancer activities of Bao‐mango peel extract (MPE). The total phenolic content (TPC) of MPE was 280.57 ± 7.95 μg quercetin per g of powder. Based on antioxidant activity analyses, MPE had IC₅₀ values of 35.09 and 23.80 ± 0.48 μg/mL for 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) and 2,2′‐azino‐bis‐3‐ethylbenzthiazoline‐6‐sulphonic acid (ABTS) radical scavenging activities, respectively. Additionally, MPE exerted an inhibitory action against MDA‐MB‐231 breast cancer cells with an IC₅₀ of 39.08 ± 5.22 μg/mL. Furthermore, nanoencapsules loaded with MPE using chitosan‐coated poly lactic‐co‐glycolic acid (CS‐PLGA‐(MPE)) were also prepared. It exhibited spherical morphology with an average size of 251.90 ± 19.61 nm. Encapsulation efficiency (EE) of nanoparticles was 30.48 %. Moreover, the CS‐PLGA‐(MPE) exhibited higher anticancer activity by affecting cell viability and inhibiting the cell migration and invasion of MDA‐MB‐231 breast cancer cells, compared to the free MPE. Therefore, these findings indicated that MPE and CS‐PLGA‐(MPE) nanoparticles could be promising alternatives to chemicals used for breast cancer treatment.

Breast cancer is one of the most common cancers in women worldwide. Conventional cancer chemotherapy always has adverse side effects on the patient’s healthy tissues. Consequently, combining pore-forming toxins with cell-targeting peptides (CTPs) is a promising anticancer strategy for selectively destroying cancer cells. Here, we aim to improve the target specificity of the BinB toxin produced from Lysinibacillus sphaericus (Ls) by fusing a luteinizing hormone-releasing hormone (LHRH) peptide to its pore-forming domain (BinB_C) to target MCF-7 breast cancer cells as opposed to human fibroblast cells (Hs68). The results showed that LHRH-BinB_C inhibited MCF-7 cell proliferation in a dose-dependent manner while leaving Hs68 cells unaffected. BinB_C, at any concentration tested, did not affect the proliferation of MCF-7 or Hs68 cells. In addition, the LHRH-BinB_C toxin caused the efflux of the cytoplasmic enzyme lactate dehydrogenase (LDH), demonstrating the efficacy of the LHRH peptide in directing the BinB_C toxin to damage the plasma membranes of MCF-7 cancer cells. LHRH-BinB_C also caused MCF-7 cell apoptosis by activating caspase-8. In addition, LHRH-BinB_C was predominantly observed on the cell surface of MCF-7 and Hs68 cells, without colocalization with mitochondria. Overall, our findings suggest that LHRH-BinB_C could be investigated further as a potential cancer therapeutic agent.

In this study, we report the green synthesis of silver nanoparticles (AgNPs) from Morus alba or white mulberry leaf extract (MLE) and assess their antibacterial and anticancer potential. The GC–MS analysis of MLE confirmed the existence of phenolic compounds, serving as reducing, capping, and stabilizing agents in the biosynthesis of AgNPs. The MLE-AgNPs were spherical, with an average particle size of 20–44.5 nm and a face-centered cubic structure. EDX spectra confirmed the formation of AgNPs, and a negative zeta potential value (−14.5 mV) suggested their physicochemical stability. Excellent antibacterial activity was demonstrated by MLE-AgNPs against Acinetobacter baumannii strains with a MIC of 2 μg/mL, while good activity was observed against other Gram-negative (Escherichia coli and Salmonella typhimurium) and Gram-positive (Bacillus subtilis and Staphylococcus aureus) bacteria with a MIC of 32 μg/mL. In vitro cytotoxic effects on MCF-7 (human breast cancer cells) and MCF-10A (normal human mammary epithelial cells) were investigated by the MTT assay. The half-maximal inhibitory concentrations (IC₅₀) against MCF-7 cells were 18 and 33 μg/mL for MLE-AgNPs and MLE, respectively, with no effect on normal MCF-10A cells. Altogether, the results support the high antibacterial and anticancer potential of biosynthesized AgNPs by white mulberry leaf extract.