Photodynamic therapy (PDT) is a clinically approved therapeutic option for the treatment of various types of cancer. PDT calls for the application of photosensitizers (PSs) and photoactivation with a particular light wavelength while tissue oxygen is present. Anticancer efficacy depends on the combination of these three substrates leading to the generation of cytotoxic reactive oxygen species (ROS) that promote apoptosis, necrosis, and autophagy of cancer cells. However, one of the biggest problems with conventional PDT is the poor accumulation and targeting of PSs to tumor tissues, resulting in undesirable side effects and unfavorable therapeutic outcomes. To overcome this, new photosensitizers have been developed through bioconjugation and encapsulation with targeting molecules, such as peptides, allowing a better accumulation and targeting in tumor cells. Several studies have been conducted to test the efficacy of several peptide-conjugated photosensitizers and improve PDT efficacy. This review aims to present current insights into various types of peptide-conjugated photosensitizers, with the goal of enhancing cancer treatment efficacy, addressing the limitations of conventional PDT, and expanding potential applications in medicine.

This study explores the effectiveness of the antineoplastic agent 5-FU in cancer cells by leveraging the unique properties of cationic antimicrobial peptides (CAMPs) and cell-penetrating peptides (CPPs). Traditional anticancer therapies face substantial limitations, including unfavorable pharmacokinetic profiles and inadequate specificity for tumor sites. These drawbacks often necessitate higher therapeutic agent doses, leading to severe toxicity in normal cells and adverse side effects. Peptides have emerged as promising carriers for targeted drug delivery, with their ability to selectively deliver therapeutics to cells expressing specific receptors. This enhances intracellular drug delivery, minimizes drug resistance, and reduces toxicity. In this research, we comprehensively evaluate the ADMET (absorption, distribution, metabolism, excretion, and toxicity) properties of various AMPs and CPPs to gain insights into their potential as anticancer agents. The peptide synthesis involved a solid-phase synthesis using a Liberty Microwave Peptide Synthesizer. The peptide purity was confirmed via LC-MS and HPLC methods. For the ADMET screening, computational tools were employed, assessing parameters like absorption, distribution, metabolism, excretion, and toxicity. The cell lines A549 and UM-UC-5 were cultured and treated with 5-FU, CAMPs, and CPPs. The cell viability was measured using the MTT assay. The physicochemical properties analysis revealed favorable drug-likeness attributes. The peptides exhibited potential inhibitory activity against CYP3A4. The ADMET predictions indicated variable absorption and distribution characteristics. Furthermore, we assessed the effectiveness of these peptides alone and in combination with 5-FU, a widely used antineoplastic agent, in two distinct cancer cell lines, UM-UC-5 and A549. Our findings indicate that CAMPs can significantly reduce the cell viability in A549 cells, while CPPs exhibit promising results in UM-UC-5 cells. Understanding these multifaceted effects could open new avenues for antiviral and anticancer research. Further, experimental validation is necessary to confirm the mechanism of action of these peptides, especially in combination with 5-FU.

Background/Objectives: Vascular graft infections (VGIs) represent a life-threatening complication, occurring in 0.2–6% of patients following aortic prosthetic placements. Historically, the primary focus for reducing VGIs has been on prevention. Currently, antimicrobial grafts are not available on the market. This study aimed to evaluate the efficacy of combining two antibiotics, fosfomycin and oritavancin, impregnated into the commercially available Gelweave^TM vascular graft as a prophylactic alternative against the most commonly implicated bacteria responsible for VGI. Methods: The antimicrobial activity of fosfomycin and oritavancin was assessed using the broth microdilution method, and a synergistic effect was demonstrated using the checkerboard assay against Staphylococcus epidermidis, methicillin-resistant Staphylococcus aureus, and vancomycin-resistant Enterococcus faecium. The antibiotics were impregnated into the commercial vascular graft through immersion, and the antimicrobial efficacy of the fosfomycin/oritavancin-impregnated graft was assessed over a period of 7 days. Results: Eradication of all microorganisms tested was achieved using impregnation solutions with concentrations of 40 mg/mL of fosfomycin and 256 µg/mL of oritavancin. Conclusions: Impregnation with the combination of fosfomycin/oritavancin proved to be a promising approach to prevent VGIs. Vascular grafts with impregnated antibiotics are not yet available on the market, and this work represents an important step toward the development of a new class of antimicrobial vascular grafts.