Pisum sativum Defensin 1 Eradicates Mouse Metastatic Lung Nodules from B16F10 Melanoma Cells

Abstract

Psd1 is a pea plant defensin which can be actively expressed in Pichia pastoris and shows broad antifungal activity. This activity is dependent on fungal membrane glucosylceramide (GlcCer), which is also important for its internalization, nuclear localization, and endoreduplication. Certain cancer cells present a lipid metabolism imbalance resulting in the overexpression of GlcCer in their membrane. In this work, in vitroassays using B16F10 cells showed that labeled fluorescein isothiocyanate FITC-Psd1 internalized into live cultured cells and targeted the nucleus, which underwent fragmentation, exhibiting approximately 60% of cells in the sub-G0/G1 stage. This phenomenon was dependent on GlcCer, and the participation of cyclin-F was suggested. In a murine lung metastatic melanoma model, intravenous injection of Psd1 together with B16F10 cells drastically reduced the number of nodules at concentrations above 0.5 mg/kg. Additionally, the administration of 1 mg/kg Psd1 decreased the number of lung inflammatory cells to near zero without weight loss, unlike animals that received melanoma cells only. It is worth noting that 1 mg/kg Psd1 alone did not provoke inflammation in lung tissue or weight or vital signal losses over 21 days, inferring no whole animal cytotoxicity. These results suggest that Psd1 could be a promising prototype for human lung anti-metastatic melanoma therapy.

Medicago SativaDefensin 1 (MsDef1), A Natural Tumor Targeted Sensitizer for Improving Chemotherapy: Translation from Anti-Fungal Agent to Potential Anti-Cancer Agent

“…Similarly, linear Def1 did not show any biological activity emphasizing the role of tetra sulfide folding which helps to stabilize Def1 in vivo similar to many polysulfides. These results are compatible with the reported Psd1 defensin which showed Nuclear Overhauser Effect (NOE) with carbohydrate and ceramide parts of GlcCer 25 . This is the first premise on which Def1 is proposed as a targeted tumor sensitizer.…”

“…Similarly, linear Def1 did not show any biological activity emphasizing the role of tetra sulfide folding which helps Def1 to stabilize in vivo similar to many theta defensins 34 . These results are compatible with the reported Psd1 defensin which showed Nuclear Overhauser Effect (NOE) with carbohydrate and ceramide parts of GlcCer 25 . Binding of Def1 with GucCer is the first step in mediating the cytotoxicity and is the first scientific premise on which we rationalized Def1 for a potential cancer therapy.…”

“…The low uptake of scrambled Def1-NBD by tumor cells (Fig 5E) establishes the selectivity of Def1 to tumor cells. BODIPY-labeled NaD1, similar to Def1 is reported to localize in organelles of lymphoma U937 cells 30 demonstrating the cell penetrating ability of Def1.…”

Antifungal Plant Defensins as an Alternative Tool to Combat Candidiasis

“…Murine lung metastatic melanoma model 1 mg/kg Psd1 does not only inhibit the formation of lung metastasis nodules in a murine model in vivo, but also decreases the number of inflammatory cells in lung tissues Histological analysis [80] Caco-2-polarized monolayer…”

Antimicrobial Peptides with Anti-Candida Activity

“…Cells under Psd1 treatment were not able to form aggregates, highlighting its ability to compromise this important virulence factor [ 24 ]. Apart from that, Psd1 was shown to be able to inhibit two cancer cell lines in a murine model and could be a promising drug candidate for lung melanoma metastasis treatment [ 117 ].…”