Peptide name : LfcinB

Source/Organism : Bovine lactoferrin (Lf-B)

Linear/Cyclic : Linear

Chirality : L

Peptide length: 12

C-terminal modification: Linear

N-terminal modification : Free

Non-natural peptide information: None

Assay type : MTT/MTS assay

Assay time : 30min

Activity : IC50 : > 160 µM

Cell line : HT-29

Cancer type : Colon cancer

Other activity : Immunomodulatory activity; Antihypertensive; Anti-microbial activity; Antiviral activity

Amino acid composition bar chart :

Molecular mass : 1753.151 Dalton

Aliphatic index : 0

Instability index : 92.1083

Hydrophobicity (GRAVY) : -1.941

Isoelectric point : 11.735

Charge (pH 7) : 5.7472

Aromaticity : 0.25

Molar extinction coefficient (cysteine, cystine): (11000, 11000)

Hydrophobic/hydrophilic ratio : 0.71428571

hydrophobic moment : -0.833

Missing amino acid : H,T,P,I,E,S,D,Y,L,N,A,V,G

Most occurring amino acid : K

Most occurring amino acid frequency : 3

Least occurring amino acid : F

Least occurring amino acid frequency : 1

Secondary structure fraction (Helix, Turn, Sheet): (0.3, 0, 0.2)

SMILES Notation: CSCC[C@H](NC(=O)[C@H](CCCNC(=N)N)NC(=O)[C@H](Cc1c[nH]c2ccccc12)NC(=O)[C@H](CCC(N)=O)NC(=O)[C@H](Cc1c[nH]c2ccccc12)NC(=O)[C@H](CCCNC(=N)N)NC(=O)[C@H](CCCNC(=N)N)NC(=O)[C@H](CS)NC(=O)[C@H](CCCCN)NC(=O)[C@@H](N)Cc1ccccc1)C(=O)N[C@@H](CCCCN)C(=O)N[C@@H](CCCCN)C(=O)O

1 : Pepe G, et al. Potential anticarcinogenic peptides from bovine milk. J Amino Acids. 2013; 2013:939804. doi: 10.1155/2013/939804

2 : Fadnes B, et al. Small lytic peptides escape the inhibitory effect of heparan sulfate on the surface of cancer cells. BMC Cancer. 2011; 11:116. doi: 10.1186/1471-2407-11-116

Paper title : Potential anticarcinogenic peptides from bovine milk.

Doi : https://doi.org/10.1155/2013/939804

Abstract : BOVINE MILK POSSESSES A PROTEIN SYSTEM CONSTITUTED BY TWO MAJOR FAMILIES OF PROTEINS: caseins (insoluble) and whey proteins (soluble). Caseins ( α S1, α S2, β , and κ ) are the predominant phosphoproteins in the milk of ruminants, accounting for about 80% of total protein, while the whey proteins, representing approximately 20% of milk protein fraction, include β -lactoglobulin, α -lactalbumin, immunoglobulins, bovine serum albumin, bovine lactoferrin, and lactoperoxidase, together with other minor components. Different bioactivities have been associated with these proteins. In many cases, caseins and whey proteins act as precursors of bioactive peptides that are released, in the body, by enzymatic proteolysis during gastrointestinal digestion or during food processing. The biologically active peptides are of particular interest in food science and nutrition because they have been shown to play physiological roles, including opioid-like features, as well as immunomodulant, antihypertensive, antimicrobial, antiviral, and antioxidant activities. In recent years, research has focused its attention on the ability of these molecules to provide a prevention against the development of cancer. This paper presents an overview of antitumor activity of caseins and whey proteins and derived peptides.

Paper title : Small lytic peptides escape the inhibitory effect of heparan sulfate on the surface of cancer cells.

Doi : https://doi.org/10.1186/1471-2407-11-116

Abstract : BACKGROUND: Several naturally occurring cationic antimicrobial peptides (CAPs), including bovine lactoferricin (LfcinB), display promising anticancer activities. These peptides are unaffected by multidrug resistance mechanisms and have been shown to induce a protective immune response against solid tumors, thus making them interesting candidates for developing novel lead structures for anticancer treatment. Recently, we showed that the anticancer activity by LfcinB was inhibited by the presence of heparan sulfate (HS) on the surface of tumor cells. Based on extensive structure-activity relationship studies performed on LfcinB, shorter and more potent peptides have been constructed. In the present study, we have investigated the anticancer activity of three chemically modified 9-mer peptides and the influence of HS and chondroitin sulfate (CS) on their cytotoxic activity. METHODS: Various cell lines and red blood cells were used to investigate the anticancer activity and selectivity of the peptides. The cytotoxic effect of the peptides against the different cell lines was measured by use of a colorimetric MTT viability assay. The influence of HS and CS on their cytotoxic activity was evaluated by using HS/CS expressing and HS/CS deficient cell lines. The ability of soluble HS and CS to inhibit the cytotoxic activity of the peptides and the peptides' affinity for HS and CS were also investigated. RESULTS: The 9-mer peptides displayed selective anticancer activity. Cells expressing HS/CS were equally or more susceptible to the peptides than cells not expressing HS/CS. The peptides displayed a higher affinity for HS compared to CS, and exogenously added HS inhibited the cytotoxic effect of the peptides. CONCLUSIONS: In contrast to the previously reported inhibitory effect of HS on LfcinB, the present study shows that the cytotoxic activity of small lytic peptides was increased or not affected by cell surface HS.