The anticancer activity of bovine lactoferrin is reduced by deglycosylation and it follows a different pathway in cervix and colon cancer cells.

Bovine lactoferrin (bLF) is a glycosylated protein with purported beneficial properties. The aim of this work was to determine the role of bLF glycosylation in the adhesion, internalization, and growth inhibition of cancer cells. The viability of cervix (HeLa) and colon (Caco-2) cancer cells (MTT assay and epifluorescence microscopy) was inhibited by bLF, while deglycosylated bLF (bLFdeg) had no effect. Adhesion to cell surfaces was quantified by immunofluorescence assay and showed that bLF was able to bind more efficiently to both cell lines than bLFdeg. Microscopic observations indicated that bLF glycosylation favored bLF binding to epithelial cells and that it was endocytosed through caveolin-1-mediated internalization. In addition, the mechanism of action of bLF on cancer cell proliferation was investigated by determining the amount of phosphorylated intermediates of signaling pathways such as epidermal growth factor receptor (EGFR), extracellular signal-regulated kinase (ERK) and protein kinase B (known as Akt). Chemoluminescence immunoassay of phosphorylated intermediates showed that bLF inhibited Akt phosphorylation, consistent with its growth inhibiting activity. This assay also indicated that the bLF receptor/signaling pathways may be different in the two cell lines, Caco-2 and HeLa. This work confirmed the effect of glycosylated bLF in inhibiting cancer cell growth and that glycosylation is required for optimal surface adhesion, internalization, and inhibition of the ERK/Akt pathway of cell proliferation through glycosylated cell surface receptors.

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

Liver cancer and leukemia are the fourth and first causes, respectively, of cancer death in children and adults worldwide. Moreover, cancer treatments, although beneficial, remain expensive, invasive, toxic, and affect the patient's quality of life. Therefore, new anticancer agents are needed to improve existing agents. Because bovine lactoferrin (bLF) and its derived peptides have antitumor properties, we investigated the anticancer effect of bLF and LF peptides (LFcin17-30, LFampin265-284 and LFchimera) on liver cancer HepG2 cells and leukemia Jurkat cells. HepG2 and Jurkat cells were incubated with bLF and LF peptides. Cell proliferation was quantified by an MTT assay, and cell morphology and damage were visualized by light microscopy or by phalloidin-TRITC/DAPI staining. The discrimination between apoptosis/necrosis was performed by staining with Annexin V-Alexa Fluor 488 and propidium iodide, and the expression of genes related to apoptosis was analyzed in Jurkat cells. Finally, the synergistic interaction of bLF and LF peptides with cisplatin or etoposide was assessed by an MTT assay and the combination index. The present study demonstrated that bLF and LF peptides inhibited the viability of HepG2 and Jurkat cells, inducing damage to the cell monolayer of HepG2 cells and morphological changes in both cell lines. bLF, LFcin17-30, and LFampin265-284 triggered apoptosis in both cell lines, whereas LFchimera induced necrosis. These results suggested that bLF and LF peptides activate apoptosis by increasing the expression of genes of the intrinsic pathway. Additionally, bLF and LF peptides synergistically interacted with cisplatin and etoposide. In conclusion, bLF and LF peptides display anticancer activity against liver cancer and leukemia cells, representing an alternative or improvement in cancer treatment.

Bovine lactoferrin and lactoferrin peptides affect endometrial and cervical cancer cell lines.

Cervical, uterine, and ovarian cancers are the most common malignancies of the female genital tract worldwide. Despite advances in prevention, early diagnosis, effective screening, and treatment programs, mortality remains high. Consequently, it is important to search for new treatments. The activity of bovine lactoferrin (bLF) and LF peptides against several types of cancer has been studied; however, only a few studies report the effect of bLF and LF peptides against cervical and endometrial cancers. In this study, we explored the effect of bLF as well as LF chimera and its constituent peptides LFcin17-30 and LFampin265-284 on the viability of cervical (HeLa, SiHa) and endometrial (KLE, HEC-1A) cancer cell lines. Cell proliferation was quantified with an MTT assay, cell morphological changes and damage were determined by Giemsa and phalloidin-TRITC and DAPI staining, and apoptotic and necrotic cells were identified by Alexa Fluor® 488 Annexin V and propidium iodide staining. Additionally, the effect of combinations of bLF and LF peptides with cisplatin was assessed. bLF and LF peptides inhibited the proliferation of uterine cancer cells and caused cellular morphological changes and damage to cell monolayers. bLF induced apoptosis, LFcin17-30 and LFampin265-284 induced apoptosis and necrosis, and LF chimera induced necrosis. Additionally, bLF and LF chimera showed an additive interaction with cisplatin against uterine cancer cells.