PMID: 

Biometals. 2011 Aug ;24(4):585-94. Epub 2011 Feb 16. PMID: 21327478

Abstract Title: 

Lactoferrin: an iron-binding antimicrobial protein against Escherichia coli infection.

Abstract: 

Escherichia coli (E. coli) are the most common aerobic gram-negative bacilli in a normal intestinal tract. They cause most of the intra-abdominal infections, wound infections associated with abdominal surgery, and septicemia. Most of these infections are of endogenous intestinal origin. Lactoferrin (LF) is an iron-binding glycoprotein found in milk and various external secretions. This protein has been found to have a number of biological functions, including antimicrobial, anti-cancer, antioxidant, and immunomodulatory effects. Partial degradation of LF by pepsin can give rise to peptides termed lactoferricin (LFcin) with more potent antimicrobial activity. LF and LFcin have been shown to inhibit the growth of a number of pathogenic bacteria (including E. coli and antibiotic-resistant strains), fungi, and even viruses in both in vitro and in vivo studies. We previously demonstrated that both recombinant porcine LF (pLF) produced from yeast and a synthetic 20-residue porcine LFcin peptide exhibit antimicrobial activity in vitro. In one of our recent studies, we performed pathogen challenges, including pathogenic E. coli, Staphylococcus aureus and Candida albicans, of the digestive tract of a transgenic milk-fed animal model. The results showed that LF has broad spectrum antimicrobial activity in the digestive tract and protects the mucosa of the small intestine from injury. Our following study also revealed that pLF as a feedstuff additive enhances avian immunity, including antibody formation and cell-mediated immunity. All of these results suggest that LF could be a novel natural protein in the treatment and prevention of infections with E. coli or antibiotic-resistant bacteria strains.

read more

PMID: 

Clin Cancer Res. 2004 Dec 15 ;10(24):8683-6. PMID: 15623653

Abstract Title: 

Lactoferrin down-regulates G1 cyclin-dependent kinases during growth arrest of head and neck cancer cells.

Abstract: 

The molecular mechanism of lactoferrin-induced cell growth inhibition is incompletely understood. Studying head and neck cancer cells treated with human lactoferrin, we observed growth arrest in three of four cell lines tested. This growth arrest was caused by cell cycle inhibition at the G0-G1 checkpoint. Lactoferrin-induced growth inhibition was associated with a large increase in p27 protein, accompanied by decreased phosphorylation of retinoblastoma protein, and suppression of cyclin E. Decreased levels of phosphorylated Akt were also observed in lactoferrin-sensitive cell lines after treatment. These findings suggest that in head and neck cancer cells the growth inhibitory effects of lactoferrin are mediated through a p27/cyclin E-dependent pathway that may be modulated in part by changes in Akt phosphorylation.

read more

PMID: 

Exp Oncol. 2019 Mar ;41(1):20-25. PMID: 30932415

Abstract Title: 

The influence of lactoferrin on elemental homeostasis and activity of metal-containing enzymes in rats with Walker-256 carcinosarcoma.

Abstract: 

AIM: To investigate the content of essential elements (EE): copper, zinc, magnesium, iron and calcium and the evaluation of the activity of metal-containing enzymes – ceruloplasmin (CP), myeloperoxidase (MPO) and the content of transferrin (TF) in blood plasma (BP) and tumor tissue (TT) of animals with Walker-256 carcinosarcoma treated with lactoferrin (LF).MATERIALS AND METHODS: The study of the EE content and the activity of the abovementioned enzymes was carried out on rats with Walker-256 carcinosarcoma treated with LF at the doses of 1 and 10 mg/kg of body weight. The quantitative content of EE in BP and TT of animals was determined using the inductively coupled plasma atomic emission spectroscopy (ICP-AES). Determination of CP activity, content of TF and hemochromes was performed using the method of electron paramagnetic resonance (EPR), and MPO – by unified biochemical method.RESULTS: The introduction of LF at the doses of 1 and 10 mg/kg resulted in a decrease in the ratio of Cu/Zn in BP and even more expressed decrease of Ca/Mg ratio in TT. Administration of LF, especially at a dose of 10 mg/kg, affected the increase in CP and MPO activity in BP. It has been shown that administration of LF at a dose of 10 mg/kg led to an increase in oxidative products of destruction of the hemoglobin-hemochrom system in the TT, against the background of lowering the TF content.CONCLUSIONS: The administration of LF, especially at a dose of 10 mg/kg, led to metabolic alterations associated with inhibition of the tumor process. The detected modulating effect of LF on the content of the EE and the activity of the CP and MPO may be a basis for correction of the elemental balance in carcinogenesis.

read more

PMID: 

J Dairy Sci. 2010 Jun ;93(6):2344-50. PMID: 20494139

Abstract Title: 

Apoptosis of stomach cancer cell SGC-7901 and regulation of Akt signaling way induced by bovine lactoferrin.

Abstract: 

Lactoferrin, a protein from bovine milk belonging to the transferring family proteins, contains 2 bound Fe(+3) ions. Recent research has revealed that lactoferrin exhibits not only antimicrobial activity by its high affinity for Fe(+3) but also remarkable anticancer capacity in cancer cell lines. Meanwhile, increasing evidence suggests that aberrant activation of Akt is involved in both normal cells and human cancers and that inhibition of Akt signaling pathway might be a promising strategy for cancer treatment. In the present study, we investigated the effect of the antitumor induced by exposing stomach cancer cell SGC-7901 to lactoferrin for 24 and 48 h. The cell viability was assessed by 3-(4,5)-dimethylthiahiazo(-z-yl)-3,5-di-phenytetrazoliumromide (MTT) assay and apoptosis was quantified by propidium iodide uptake and Annexin V-fluorescein isothiocyanate fluorescent probe label through flow cytometry. Our investigation indicates that inhibitory ratio of 50 microM lactoferrin for proliferation of stomach cancer cell SGC-7901 is much higher than 12.5 and 25 microM, and for the extended treatment time, the concentration of 50 microM has more efficiency than 100 microM lactoferrin. To elucidate a mechanism involved in its antitumor effect, we studied the Akt cell signaling pathway of SGC-7901 while treated by 50 microM of lactoferrin after 0, 24, and 48 h, particularly Akt phosphorylation of 2 individual residues, Ser473 and Thr308, Akt/glycogen synthase kinase-3beta, forkhead in human rhabdomyosarcoma, and nuclear factor-kappaB proteins, respectively, activated by Western blot. The expressions of Akt, phosphorylated Akt Ser473, phosphorylated Akt Thr308, phosphorylated nuclear factor-kappa b p65 Ser536, and Bcl-2 significantly decreased; however, the expressions of phosphorylated glycogen synthase kinase-3beta Ser9, phosphorylated forkhead in human rhabdomyosarcoma Ser256, and phosphorylated caspase-9 Ser196 increased in response to lactoferrin treatment in SGC-7901. These results suggest that lactoferrin inhibits Akt activation and modulates its downstream proteins phosphorylation in apoptosis of SGC-7901 human stomach cancer cells.

read more

PMID: 

Int J Nanomedicine. 2015 ;10:5123-37. Epub 2015 Aug 12. PMID: 26316745

Abstract Title: 

Lactoferrin-modified PEGylated liposomes loaded with doxorubicin for targeting delivery to hepatocellular carcinoma.

Abstract: 

Lactoferrin (Lf) is a potential-targeting ligand for hepatocellular carcinoma (HCC) cells because of its specific binding with asialoglycoprotein receptor (ASGPR). In this present work, a doxorubicin (DOX)-loaded, Lf-modified, polyethylene glycol (PEG)ylated liposome (Lf-PLS) system was developed, and its targeting effect and antitumor efficacy to HCC was also explored. The DOX-loaded Lf-PLS system had spherical or oval vesicles, with mean particle size approximately 100 nm, and had an encapsulation efficiency of 97%. The confocal microscopy and flow cytometry indicated that the cellular uptake of Lf-PLS was significantly higher than that of PEGylated liposome (PLS) in ASGPR-positive cells (P0.05). Cytotoxicity assay by MTT demonstrated that DOX-loaded Lf-PLS showed significantly stronger antiproliferative effects on ASGPR-positive HCC cells than did PLS without the Lf modification (P

read more

PMID: 

Biochem Cell Biol. 2006 Jun ;84(3):291-6. PMID: 16936799

Abstract Title: 

Bovine lactoferrin: benefits and mechanism of action against infections.

Abstract: 

Ingestion of bovine lactoferrin (bLF) has been reported to show anti-infective, anti-cancer, and anti-inflammatory effects. In particular, it has become evident that oral bLF had a beneficial effect on infections of both digestive and nondigestive tract tissue in various animal models. Furthermore, the effects of bLF have been indicated in clinical studies on patients with Helicobacter pylori infection, chronic hepatitis C, tinea pedis, and other diseases. Immunomodulation in the intestine and systemic sites has been suggested to mediate the protective effects of oral bLF against infection. Recently, we demonstrated the beneficial effects of oral bLF in influenza virus infected mice. BLF administration reduced the lung consolidation score and the number of infiltrating leukocytes in bronchoalveolar lavage fluid. We also investigated the effect of oral bLF on the transcription of genes related to immunity in the small intestine of mice using the quantitative RT-PCR method. We found that intake of bLF increased the expression of IL-12p40, IFN-beta, and NOD2. Thus, oral bLF activates the transcription of important immune-related genes in the small intestine, and such transcriptional activation may promote systemic host immunity.

read more

PMID: 

Sci Rep. 2018 12 21 ;8(1):18020. Epub 2018 Dec 21. PMID: 30575774

Abstract Title: 

Lactoferrin and lactoferricin endocytosis halt Giardia cell growth and prevent infective cyst production.

Abstract: 

Lactoferrin (LF) is an 80 KDa iron-binding glycoprotein that plays a significant role in the innate immune system and is considered to be an important microbicide molecule. It has been suggested to be effective in the treatment of giardiasis, an intestinal disease caused by the protozoan parasite G. lamblia. However, the molecular mechanisms by which LF exerts its effect on this parasite are unknown. Most of the microbicidal activity of human or bovine LF (hLF or bLF) has been associated with the N-terminal region of the mature LF – lactoferricin (LFcin). LFcin is produced by pepsin cleavage of the native protein in vitro and likely in vivo. In this work, we analyse the participation of the endocytic machinery of G. lamblia in the internalization of bLF and bLFcin and their effects on cell homeostasis. Our results show that, when bLF or bLFcin are internalized by receptor-mediated endocytosis, cell growth stops, and morphological changes are produced in the trophozoites, which ultimately will produce immature cysts. Our findings contribute to disclose the fine mechanism by which bLF and bLFcin may function as an antigiardial molecule and why they have therapeutic potential to eradicate giardiasis.

read more

PMID: 

Biochem Biophys Res Commun. 2019 01 15 ;508(3):946-952. Epub 2018 Dec 10. PMID: 30545626

Abstract Title: 

Molecular mechanisms underlying the inhibitory effects of bovine lactoferrin on osteosarcoma.

Abstract: 

Osteosarcoma (OS) is one the most common primary malignancies of the bone in children and young adults with high metastasis. The use of non-toxic naturally derived compounds is one of present strategies in OS therapy to reduce secondary effects and chemo-resistance. Lactoferrin (LF), a transferrin protein derived from milk, currently appears to be an anticancer agent. However, its suppressive effects on OS have not been fully investigated. Therefore, we aimed to examine the molecular mechanism underlying the inhibitory effects of bovine LF (bLF) on OS. OS cell lines (NOS1, U2OS, MG63, and 143B) and an osteoblastic (ST2) were treated with bLF. Effects of bLF on OS-cell proliferation and migration were examined by proliferation and wound-healing assays. Expression levels of low-density-lipoprotein-receptor-related protein 1 (LRP1) and cytokines including interleukin-1 beta (IL-1β), IL-6, and receptor-activator of nuclear factor kappa-Β ligand (RANKL) were measured using western blotting. Osteoclast formation was examined by co-culture of 143B, ST2, and bone marrow cells. We found that bLF down-regulated IL-1β, IL-6, and RANKL expression and suppressed phosphorylation ofnuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) p65 in 143B cells; bLF also drastically suppressed 143B-activated RANKL production in ST2 cells. This may have contributed to the reduction in the number of differentiated osteoclasts. Taken together, these data reveal that bLFdown-regulates NF-κB to attenuate proliferation, migration, and bone resorption in OS and the OS-microenvironment. This study provides new findings and the precise underlying mechanisms of the inhibitory effects of bLF on OS. bLF can be a possible therapeutic agent for OS patients.

read more

PMID: 

J Dairy Sci. 2013 Apr ;96(4):2095-2106. Epub 2013 Feb 22. PMID: 23462173

Abstract Title: 

Bovine lactoferrin inhibits lung cancer growth through suppression of both inflammation and expression of vascular endothelial growth factor.

Abstract: 

Lung cancers are among the most common cancers in the world, and the search for effective and safe drugs for the chemoprevention and therapy of pulmonary cancer has become important. In this study, bovine lactoferrin (bLF) was used in both in vitro and in vivo approaches to investigate its activity against lung cancer. A human lung cancer cell line, A549, which expresses a high level of vascular endothelial growth factor (VEGF) under hypoxia, was used as an in vitro system for bLF treatment. A strain of transgenic mice carrying the human VEGF-A165 (hVEGF-A165) gene, which induces pulmonary tumors, was used as an in vivo lung cancer therapy model. We found that bLF significantly decreased proliferation of A549 cells by decreasing the expression of VEGF protein in a dose-dependent manner. Furthermore, oral administration of bLF at 300 mg/kg of body weight 3 times a week for 1.5 mo to the transgenic mice overexpressing hVEGF-A165 significantly eliminated expression of hVEGF-A165 and suppressed the formation of tumors. Additionally, treatment with bLF significantly decreased the levels of proinflammatory cytokines, such as tumor necrosis factor-α, and antiinflammatory cytokines, such as IL-4 and IL-10. Levels of IL-6, which is both a proinflammatory and an antiinflammatory cytokine, were also reduced. Treatment with bLF decreased levels of tumor necrosis factor-α, IL-4, IL-6, and IL-10 cytokines, resulting in limited inflammation, whichthen restricted growth of the lung cancer. Our results revealed that bLF is an inhibitor of angiogenesis and blocks lung cell inflammation; as such, it has considerable potential for therapeutic use in the treatment of lung cancer.

read more

PMID: 

PLoS One. 2018 ;13(1):e0191683. Epub 2018 Jan 30. PMID: 29381751

Abstract Title: 

Molecular mechanism of inhibitory effects of bovine lactoferrin on the growth of oral squamous cell carcinoma.

Abstract: 

BACKGROUND: Lactoferrin (LF), a member of the transferrin family, recently has been demonstrated to have anticancer effects on various cancers including oral squamous cell carcinoma (OSCC). However, little is known about the underlying mechanisms of its effects on OSCC. Therefore, we aimed to investigate the mechanism of the suppressive effects of bovine LF (bLF) on the growth of OSCC cells.METHODS: In the current study, HSC2, HSC3, HSC4 and normal human oral keratinocytes (RT7) cell lines were tested with bLF 1, 10, and 100μg/ml. The effects and detail mechanisms of bLF on proliferation and apoptosis of cells were investigated using flow cytometry and western blotting.RESULTS: We found that bLF (1, 10, and 100μg/ml) induced activation of p53, a tumor suppressor gene, is associated with the induction of cell cycle arrest in G1/S phase and apoptosis in OSCC. Moreover, bLF downregulated the phosphorylation of Akt and activated suppressor of cytokine signaling 3 (SOCS3), thereby attenuating multiple signaling pathways including mTOR/S6K and JAK/STAT3. Interestingly, we revealed that bLF exerted its effect selectively against HSC3 but not on RT7 via different effects on the phosphorylation status of NF-κB and Akt.CONCLUSION: This is the first report showing that bLF selectively suppresses proliferation through mTOR/S6K and JAK/STAT3 pathways and induction of apoptosis in OSCC. This study provides important new findings, which might be useful in the prevention and treatment of OSCC.

read more