Antitumor activity of bovine lactoferrin and its derived peptides against HepG2 liver cancer cells and Jurkat leukemia cells

Single molecule recognition of CD95 receptors on the surface of HepG2 cells under the curcumin

Hepatocellular carcinoma (HCC) is a serious concern worldwide. The published reports showed that aberrant CD95 receptor expression plays a critical role in apoptosis in liver cancer. While curcumin has shown promise in inducing apoptosis in liver cancer cells, its direct effects on CD95 expression during this process have not been thoroughly investigated. This study aims to quantitatively assess the expression of the CD95 receptor in HepG2 cells treated with different concentrations of curcumin using techniques such as fluorescence staining, single-molecule force spectroscopy (SMFS), and single-molecule recognition imaging (SMRI). Fluorescence staining results indicate a significant increase in CD95 expression following curcumin treatment. For the first time, SMFS and SMRI techniques were used to directly reveal the binding sites of CD95 on the cell membrane, with the number of binding sites increasing as the curcumin concentration increased. Additionally, the binding force between an antibody-modified probe and CD95 was strengthened with curcumin treatment, suggesting that curcumin enhances both the quantity and affinity of CD95 binding sites. This study provides new insights into curcumin-induced CD95-mediated apoptosis in liver cancer cells and highlights the potential of AFM techniques for investigating drug mechanisms. Overall, these findings may inform innovative therapeutic strategies for liver cancer and improve drug design processes.

Lactoferrin in cancer: Focus on mechanisms and translational medicine

Lactoferrin is an iron-binding glycoprotein that provides natural protective effects to the human body. Its biological properties, including antibacterial, antiviral, anti-inflammatory, immune-regulatory, and iron metabolism-regulating functions, have been extensively studied. With further research, lactoferrin's impact on tumorigenesis and tumor microenvironment has become increasingly evident, as it inhibits tumor proliferation, invasion, and metastasis through multiple pathways. This article summarizes the molecular mechanisms underlying lactoferrin's anticancer effects, explores its association with the malignant progression of various cancers, and highlights its clinical translational potential as a potential cancer biomarker and drug delivery carrier to enhance anticancer therapy efficiency. Due to the high safety profile of lactoferrin, its widespread application in the field of cancer treatment is highly anticipated.

Anticancer potential of lactoferrin: effects, drug synergy and molecular interactions

Cancer treatment is among today's most active and challenging research fields. In recent years, significant progress has been made in developing new cancer therapies, including nutraceuticals and natural compounds with anticancer properties. Lactoferrin, a glycoprotein present in mammals, is of significant interest due to its pleiotropic behavior, demonstrating a broad spectrum of biological activities such as antimicrobial, antioxidant, anti-inflammatory, immunomodulatory, and anticancer effects. In this review, we examine the current knowledge of Lf's role in cancer. In addition, it exhibits a synergistic effect along with conventional drugs, potentially enhancing their efficacy and, at the same time, reducing the side effects associated with most traditional therapies. However, it is essential to consider the precise molecular mechanism by which Lf exerts its antitumor activity. Searching interactions with several molecules can provide insight into this mechanism. Additionally, finding lactoferrin receptors can improve the strategies for the specific release of the conjugates. For all these reasons, Lactoferrin becomes a potential therapeutic agent that should be examined in depth.

Inhibitory Effects of Bovine Lactoferricin-Lactoferrampin on Senecavirus A and Foot-and-Mouth Disease Virus with Recombinant Lactobacillus Oral Treatment in Mice

Foot-and-mouth disease virus (FMDV) and Senecavirus A (SVA) have similar pathogenic characteristics, and both are important pathogens that harm the livestock industry. Studies have shown that lactoferrin peptides can inhibit the replication of various viruses and enhance the body's immune functions. Based on this, in the present study, we aimed to investigate the effects of bovine lactoferricin-lactoferrampin (LFCA) on replicating FMDV and SVA and to analyze its role in the cellular antioxidant response caused by viral infection; in addition, we fed mice with constructed recombinant Lactobacillus reuteri expressing LFCA. Treatment with LFCA at different stages significantly inhibited the replication of both SVA and FMDV. Pretreatment before SVA infection achieved an inhibition rate of up to 94.9%, while treatment during the FMDV replication stage achieved an inhibition rate of 74.3%. After infection with either virus, intracellular ROS and MDA levels were significantly reduced, as was GSH-Px activity. However, SOD activity showed no significant difference, compared with the virus-exposed group, and remained at a high level, suggesting an increased cellular antioxidant capacity. LFCA treatment significantly increased the transcription levels of the Nrf2, Ho-1, and Nqo1 genes. In mouse experiments, the LFCA-treated group showed significantly lower viral loads in lung and intestinal tissues, compared with the SVA infection group, validating LFCA's protective effect against SVA infection. These findings demonstrate the potential of LFCA as an antiviral drug.

Lactoferrin: Properties and Potential Uses in the Food Industry

Lactoferrin (LF) is an 80 kDa glycoprotein that contains approximately 700 amino acids and is a member of the transferrin family. The essential properties of LF, including antimicrobial, antiviral, anticancer, anti-inflammatory, antioxidant, and probiotic effects, have been studied for decades. The iron chelation activity of LF is significantly associated with its antimicrobial, anti-inflammatory, and antioxidant properties. Owing to its probiotic and prebiotic activity, LF also facilitates the growth of beneficial microorganisms and iron-defense immediate-effect properties on pathogens. Additionally, the ability to regulate cell signaling pathways and immune responses makes LF a prominent modulatory protein. These diverse characteristics of LF have gained interest in its therapeutic potential. Studies have suggested that LF could serve as an alternative source to antibiotics in severe infections and illnesses. LF has also gained interest in the food industry for its potential as an additive to fortify products such as yogurt, infant formula, and meat derivatives while also improving the shelf life of foods and providing antimicrobial and antioxidant activity. Prior to using LF in the food industry, the safety and toxicity of food processing are necessary to be investigated. These safety investigations are crucial for addressing potential harm or side effects and ensuring a healthy lifestyle. This review discusses the attributes and safety of LF, particularly its exploitation in the food industry.

Lactoferrin-Derived Peptide Chimera Induces Caspase-Independent Cell Death in Multiple Myeloma

Lactoferrin-derived peptide chimera is a synthetic peptide that mimics the functional unit of lactoferrin with antibacterial activity. Although LF has anticancer effects, to the best of our knowledge, its effects on multiple myeloma have not yet been studied. We explored the potential of a lactoferrin-derived chimera for multiple myeloma treatment, a malignant clonal plasma cell bone marrow disease. The lactoferrin-derived chimera effectively inhibited MM1S, MM1R, and RPMI8226 multiple myeloma cell growth, and induced the early and late phases of apoptosis, but not in normal peripheral blood mononuclear cells. Furthermore, the lactoferrin-derived chimera modulates the relative expression of genes involved in survival, apoptosis, and mitochondrial dysfunction at the transcriptional level. Mitochondrial analysis revealed that lactoferrin-derived chimera triggered oxidative stress in multiple myeloma cells, leading to reactive oxygen species generation and a decline in mitochondrial membrane potential, resulting in mitochondrial dysfunction. Although lactoferrin-derived chimera did not cause caspase-dependent cell death, it induced nuclear translocation of apoptosis-inducing factor and endonuclease G, indicating the initiation of caspase-independent apoptosis. Overall, the lactoferrin-derived chimera induces caspase-independent programmed cell death in multiple myeloma cell lines by increasing the nuclear translocation of apoptosis-inducing factor/endonuclease G. Therefore, it has potential for multiple myeloma cancer therapies.

Lactoferrin Binds through Its N-Terminus to the Receptor-Binding Domain of the SARS-CoV-2 Spike Protein

Since Coronavirus disease 2019 (COVID-19) still presents a considerable threat, it is beneficial to provide therapeutic supplements against it. In this respect, glycoprotein lactoferrin (LF) and lactoferricin (LFC), a natural bioactive peptide yielded upon digestion from the N-terminus of LF, are of utmost interest, since both have been shown to reduce infections of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), the virus responsible for COVID-19, in particular via blockade of the virus priming and binding. Here, we, by means of biochemical and biophysical methods, reveal that LF directly binds to the S-protein of SARS-CoV-2. We determined thermodynamic and kinetic characteristics of the complex formation and mapped the mutual binding sites involved in this interaction, namely the N-terminal region of LF and the receptor-binding domain of the S-protein (RBD). These results may not only explain many of the observed protective effects of LF and LFC in SARS-CoV-2 infection but may also be instrumental in proposing potent and cost-effective supplemental tools in the management of COVID-19.

Production of Bioactive Porcine Lactoferrin through a Novel Glucose-Inducible Expression System in Pichia pastoris: Unveiling Antimicrobial and Anticancer Functionalities

Lactoferrin (LF) stands as one of the extensively investigated iron-binding glycoproteins within milk, exhibiting diverse biological functionalities. The global demand for LF has experienced consistent growth. Biotechnological strategies aimed at enhancing LF productivity through microbial expression systems offer substantial cost-effective advantages and exhibit fewer constraints compared to traditional animal bioreactor technologies. This study devised a novel recombinant plasmid, wherein the AOX1 promoter was replaced with a glucose-inducible G1 promoter (PG1) to govern the expression of recombinant porcine LF (rpLF) in Pichia pastoris GS115. High-copy-number PG1-rpLF yeast clones were meticulously selected, and subsequent induction with 0.05 g/L glucose demonstrated robust secretion of rpLF. Scaling up production transpired in a 5 L fermenter, yielding an estimated rpLF productivity of approximately 2.8 g/L by the conclusion of glycerol-fed fermentation. A three-step purification process involving tangential-flow ultrafiltration yielded approximately 6.55 g of rpLF crude (approximately 85% purity). Notably, exceptional purity of rpLF was achieved through sequential heparin and size-exclusion column purification. Comparatively, the present glucose-inducible system outperformed our previous methanol-induced system, which yielded a level of 87 mg/L of extracellular rpLF secretion. Furthermore, yeast-produced rpLF demonstrated affinity for ferric ions (Fe3+) and exhibited growth inhibition against various pathogenic microbes (E. coli, S. aureus, and C. albicans) and human cancer cells (A549, MDA-MB-231, and Hep3B), similar to commercial bovine LF (bLF). Intriguingly, the hydrolysate of rpLF (rpLFH) manifested heightened antimicrobial and anticancer effects compared to its intact form. In conclusion, this study presents an efficient glucose-inducible yeast expression system for large-scale production and purification of active rpLF protein with the potential for veterinary or medical applications.

Lactoferricin B Combined with Antibiotics Exhibits Leukemic Selectivity and Antimicrobial Activity

The fusion of penetrating peptides (PPs), e.g., cell penetration peptides (CPPs) or antimicrobial peptides (AMPs), together with antimicrobial agents is an expanding research field. Specific AMPs, such as lactoferricin B (LfcinB), have demonstrated strong antibacterial, antifungal, and antiparasitic activity, as well as valuable anticancer activity, proving beneficial in the development of anticancer conjugates. The resulting conjugates offer potential dual functionality, acting as both an anticancer and an antimicrobial agent. This is especially necessary in cancer treatment, where microbial infections pose a critical risk. Leukemic cells frequently exhibit altered outer lipid membranes compared to healthy cells, making them more sensitive to compounds that interfere with their membrane. In this study, we revisited and reanalyzed our earlier research on LfcinB and its conjugates. Furthermore, we carried out new experiments with a specific focus on cell proliferation, changes in membrane asymmetric phosphatidylserine location, intracellular reactive oxygen species (ROS) generation, mitochondrial functions, and in vitro bacterial topoisomerase inhibition.

Enhanced Cellular Uptake and Transport of Bovine Lactoferrin Using Pectin- and Chitosan-Modified Solid Lipid Nanoparticles

AIM

The aim of this project is to use pectin- and chitosan-modified solid lipid nanoparticles for bovine lactoferrin to enhance its cellular uptake and transport.

METHODS

Solid lipid particles containing bovine lactoferrin (bLf) were formulated through the solvent evaporation technique, incorporating stearic acid along with either chitosan or pectin modification. bLf cellular uptake and transport were evaluated in vitro using the human adenocarcinoma cell line Caco-2 cell model.

RESULTS AND DISCUSSION

The bLf-loaded SLPs showed no significant effect on cytotoxicity and did not induce apoptosis within the eight-hour investigation. The use of confocal laser scanning microscopy confirmed that bLf follows the receptor-mediated endocytosis, whereas the primary mechanism for the cellular uptake of SLPs was endocytosis. The bLf-loaded SLPs had significantly more cellular uptake compared to bLf alone, and it was observed that this impact varied based on the time, temperature, and concentration. Verapamil and EDTA were determined to raise the apparent permeability coefficients (App) of bLf and bLf-loaded SLPs.

CONCLUSION

This occurred because they hindered efflux by interacting with P-glycoproteins and had a penetration-enhancing influence. These findings propose the possibility of an additional absorption mechanism for SLPs, potentially involving active transportation facilitated by the P-glycoprotein transporter in Caco-2 cells. These results suggest that SLPs have the potential to be applied as effective carriers to improve the oral bioavailability of proteins and peptides.

Biomedical and Nutritional Applications of Lactoferrin

Lactoferrin (Lf) is a glycoprotein belonging to the transferrin family, which can be found in mammalian milk. It was first isolated from bovine milk in the 1930s, and later in the 1960s, it was determined from human milk. This multifunctional protein has the specific ability to bind iron. It plays various biological roles, such as antibacterial, antiviral, antifungal, anti-tumour, anti-obesity, antioxidant, anti-inflammatory and immunomodulatory activities. There are several studies describing its use against in various cancer cell lines (e.g., liver, lung and breast) and the glycoprotein has even been reported to inhibit the development of experimental metastases in mice. Previous studies also suggest Lf-mediated neuroprotection against age-related neurodegenerative diseases and it is also expected to attenuate aging. More recently, Lf has been proposed as a potential approach in COVID-19 prophylaxis. In this review, we discuss the recent developments about the biological activities of this pleiotropic glycoprotein that will reason the exploitation of its biomedical and supplementary nutritional value.

Current research status of anti-cancer peptides: Mechanism of action, production, and clinical applications

The escalating rate of cancer cases, together with treatment deficiencies and long-term side effects of currently used cancer drugs, has made this disease a global burden of the 21st century. The number of breast and lung cancer patients has sharply increased worldwide in the last few years. Presently, surgical treatment, radiotherapy, chemotherapy, and immunotherapy strategies are used to cure cancer, which cause severe side effects, toxicities, and drug resistance. In recent years, anti-cancer peptides have become an eminent therapeutic strategy for cancer treatment due to their high specificity and fewer side effects and toxicity. This review presents an updated overview of different anti-cancer peptides, their mechanisms of action and current production strategies employed for their manufacture. In addition, approved and under clinical trials anti-cancer peptides and their applications have been discussed. This review provides updated information on therapeutic anti-cancer peptides that hold great promise for cancer treatment in the near future.

Lactoferrin: Antimicrobial impacts, genomic guardian, therapeutic uses and clinical significance for humans and animals

Lactoferrin (LF) is a protein found in several bodily fluids, such as milk. This protein has a diverse range of functions and is evolutionarily conserved. Lactoferrin is a multifunction protein with distinct biological abilities affecting mammals' immune structures. Reports indicated that the daily uptake of LF from dairy products is unsatisfactory in detecting further health-promoting abilities. Research has shown that it protects against infection, mitigates cellular senescence, and improves nutritional quality. Additionally, LF is being studied as a potential treatment for various diseases and conditions, including gastrointestinal issues and infections. Studies have also demonstrated its effectiveness against various viruses and bacteria. In this article, we'll look closer at the structure of LF and its various biological activities, including its antimicrobial, anti-viral, anti-cancer, anti-osteoporotic, detoxifying, and immunomodulatory properties. More specifically, the protective effect of LF against oxidative DNA damage was also clarified through its ability to abolish DNA damaging issues without interfacing with host genetic material. Fortification with LF protects mitochondria dysfunction syndromes via sustaining redox status and biogenesis and suppressing apoptosis and autophagy singling. Additionally, we'll examine the potential benefits of lactoferrin and provide an overview of recent clinical trials conducted to examine its use in laboratory and living models.

Time to Kill and Time to Heal: The Multifaceted Role of Lactoferrin and Lactoferricin in Host Defense

Lactoferrin is an iron-binding glycoprotein present in most human exocrine fluids, particularly breast milk. Lactoferrin is also released from neutrophil granules, and its concentration increases rapidly at the site of inflammation. Immune cells of both the innate and the adaptive immune system express receptors for lactoferrin to modulate their functions in response to it. On the basis of these interactions, lactoferrin plays many roles in host defense, ranging from augmenting or calming inflammatory pathways to direct killing of pathogens. Complex biological activities of lactoferrin are determined by its ability to sequester iron and by its highly basic N-terminus, via which lactoferrin binds to a plethora of negatively charged surfaces of microorganisms and viruses, as well as to mammalian cells, both normal and cancerous. Proteolytic cleavage of lactoferrin in the digestive tract generates smaller peptides, such as N-terminally derived lactoferricin. Lactoferricin shares some of the properties of lactoferrin, but also exhibits unique characteristics and functions. In this review, we discuss the structure, functions, and potential therapeutic uses of lactoferrin, lactoferricin, and other lactoferrin-derived bioactive peptides in treating various infections and inflammatory conditions. Furthermore, we summarize clinical trials examining the effect of lactoferrin supplementation in disease treatment, with a special focus on its potential use in treating COVID-19.