Peptide-drug-conjugates (PDCs) are being developed as an effective strategy to specifically deliver cytotoxic drugs to cancer cells. However one of the challenges to their successful application is the relatively low stability of peptides in the blood, liver and kidneys. Since AuNPs seem to have a longer plasma half-life than PDCs, one approach to overcoming this problem would be to conjugate the PDCs to gold nanoparticles (AuNPs), as these have demonstrated favorable physico-chemical and safety properties for drug delivery systems. We set out to test whether PEG coated-AuNPs could provide a suitable platform for the non-covalent loading of pre-formed PDCs and whether this modification would affect the bioavailability of the PDCs and their cytotoxicity toward target cancer cells. Peptides specifically internalized by A20 murine lymphoma cells were isolated from a phage library displaying 7mer linear peptides. Peptide specificity was validated by flow cytometry and confocal microscopy. PDCs were synthesized containing a selected peptide (P4) and either chlorambucil (Chlor), melphalan (Melph) or bendamustine (Bend). Gold nanoparticles were sequentially coated with citrate, PEG-6000 and then PDC (PDC-PEG-AuNP). The physico-chemical properties of the coated particles were analyzed by electrophoresis, TEM, UV–VIS and FTIR. Stability of free and PDC-coated AuNP was determined. Biopanning of the phage library resulted in discovery of several novel peptides that internalized into A20 cells. One of these (P4) was used to synthesize PDCs containing either Chlor, Melph or Bend. All three PDCs specifically killed A20 target cells, however they had short half-lives ranging from 10.6 to 15.4 min. When coated to PEG-AuNPs, the half-lives were extended to 21.0–22.3 h. The PDC-PEG-AuNPs retained cytotoxicity towards the target cells. Moreover, whereas pre-incubation for 24 h of free PDCs almost completely abolished their cytotoxic activity, the PDC-PEG-AuNPs were still active even after 72 h pre-incubation. Peptide-drug-conjugates hold potential for improving the target efficacy of chemotherapeutic drugs, however their short half-lives may limit their application. This hurdle can be overcome by easily conjugating them to gold nanoparticles. This conjugation also opens up the possibility of developing slow release formulations of targeted drug delivery systems containing PDCs.

The epidermal growth factor–epidermal growth factor receptor (EGF-EGFR) pathway has become the main focus of selective chemotherapeutic intervention. As a result, two classes of EGFR inhibitors have been clinically approved, namely monoclonal antibodies and small molecule kinase inhibitors. Despite an initial good response rate to these drugs, most patients develop drug resistance. Therefore, new treatment approaches are needed. In this work, we aimed to find a new EGFR-specific, short cyclic peptide, which could be used for targeted drug delivery. Phage display peptide technology and biopanning were applied to three EGFR expressing cells, including cells expressing the EGFRvIII mutation. DNA from the internalized phage was extracted and the peptide inserts were sequenced using next-generation sequencing (NGS). Eleven peptides were selected for further investigation using binding, internalization, and competition assays, and the results were confirmed by confocal microscopy and peptide docking. Among these eleven peptides, seven showed specific and selective binding and internalization into EGFR positive (EGFR+ve) cells, with two of them—P6 and P9—also demonstrating high specificity for non-small cell lung cancer (NSCLC) and glioblastoma cells, respectively. These peptides were chemically conjugated to camptothecin (CPT). The conjugates were more cytotoxic to EGFR+ve cells than free CPT. Our results describe a novel cyclic peptide, which can be used for targeted drug delivery to cells overexpressing the EGFR and EGFRvIII mutation.

Grapevines are susceptible and responsive to their surrounding environment. Factors such as climate region and terroir are known to affect polyphenolic compounds in wine and therefore, its quality. The uniqueness of the terroir in Israel is the variety of soil types and the climatic conditions, ranging from Mediterranean to arid climates. Thus, understanding the effects of climate on grapevine performance in Israel may be a test case for the effect of climate change on grapevine at other areas in the future. First, we present a preliminary survey (2012–2014) in different climate zones and terroirs, which showed that trans-resveratrol concentrations in Merlot and Shiraz were high, while those of Cabernet Sauvignon were significantly lower. A further comprehensive countrywide survey (2016) of Merlot wines from 62 vineyards (53 wineries) compared several phenolic compounds’ concentrations between five areas of different climate and terroir. Results show a connection between trans-resveratrol concentrations, variety, and terroir properties. Furthermore, we show that trans-resveratrol concentrations are strongly correlated to humidity levels at springtime, precipitation, and soil permeability. This work can be considered a glimpse into the possible alterations of wine composition in currently moderate-climate wine-growing areas.

Background/Objectives: Here, we report on the synthesis and biological evaluation of a novel peptide–drug conjugate, P6-SN38, which consists of the EGFR-specific short cyclic peptide, P6, and the Topo I inhibitor SN38, which is a bioactive metabolite of the anticancer drug irinotecan. Methods: SN38 is attached to the peptide at position 20 of the E ring’s tertiary hydroxyl group via a mono-succinate linker. Results: The developed peptide–drug conjugate (PDC) exhibited sub-micromolar anticancer activity on EGFR-positive (EGFR+) cell lines but no effect on EGFR-negative (EGFR−) cells. In vivo studies have shown that this PDC specifically accumulates in EGFR+ non-small cell lung cancer (NSCLC) xenografts and presents superior anticancer activity compared to the EGFR-specific antibody cetuximab (Erbitux^TM) and free SN38. The 10 mg/kg dose of P6-SN38 in a side-by-side EGFR+/EGFR− xenograft shows eradication of the EGFR+ tumor with good tolerance, but no inhibition of tumor growth of the EGFR− counterpart. Conclusions: The PDC examined in this study was proven to be highly efficient for NSCLC, broadening its utilization for targeted cancer therapy in EGFR overexpressed cancers.

Oxidative-stress-induced neuronal injury is a major contributor to neurodegenerative diseases, underscoring the need for novel neuroprotective strategies. Natural products with antioxidant and mitochondrial-stabilizing properties are increasingly recognized as promising multi-target therapeutics. Ficus benjamina L., a member of the Moraceae family, is rich in flavonoids and traditionally used in Asian ethnomedicine for wound healing, inflammation, and weakness, with related Ficus species documented in the Bencao Gangmu (Compendium of Materia Medica) for circulation and detoxification disorders. However, its neuroprotective potential has not been systematically evaluated. In this study, we explored the neuroprotective potential of a flavonoid-enriched 80% methanolic leaf extract of F. benjamina by evaluating its capacity to mitigate oxidative stress in neuronal cells and a murine optic nerve crush (ONC) injury model. We observed in SH-SY5Y cells that cell viability was preserved after pre-treatment using the extract, mitochondrial respiration and the membrane potential were maintained, and gene expression was modulated by upregulation of BCL-2 (B-cell lymphoma 2), BCL-xL (B-cell lymphoma-extra large), X) SOD2 (Superoxide Dismutase), CAT (Catalase), and BDNF (Brain-Derived Neurotrophic Factor). Intravitreal delivery of the extract in vivo resulted in a marked increase in the survival of retinal ganglion cells following ONC injury. Caffeic acid, quercetin-3-O-rutinoside, and kaempferol-3-O-rutinoside were identified as major constituents in phytochemical profiling. These results indicate that F. benjamina exerts multi-target neuroprotective actions, mediated via mitochondrial regulation, enhancement of antioxidation defenses, and modulation of apoptotic pathways. The findings also substantiate the contemporary pharmacological relevance underscoring the ethnomedicinal use of Ficus species and highlight the potential of F. benjamina as a promising candidate for developing integrative therapeutic approaches to target neurodegenerative diseases driven by oxidative stress.