Marine lysozyme from a marine bacterium that inhibits angiogenesis and tumor growth

Abstract

Recent studies suggest that lysozyme, rich in hen egg, has an antitumor function. In the present study, we investigated the antitumor and antiangiogenesis effects of a newly isolated marine lysozyme both in vitro and in vivo. First, we showed that this marine-derived lysozyme specifically inhibits the proliferation of endothelial cells (ECV304) in a dose-dependent manner with no cytotoxicity (IC(50) = 3.64 microM). Second, we showed that this marine lysozyme directly suppresses neovascularization in chicken embryos using chorioallantoic membrane assay. Third, we demonstrated that this marine lysozyme markedly inhibits tumor growth in mice bearing either sarcoma 180 or hepatoma 22. Unexpectedly, hen egg lysozyme has no effects on the proliferation of endothelial cells in vitro or neovascularization in chicken embryos or tumor growth in nude mice at the same dosage range. Taken together, our studies clearly show that the newly identified marine lysozyme is a potent antitumor molecule, which may inhibit tumor growth and inhibit angiogenesis. We believe that this marine lysozyme may have a therapeutic value in antitumor drug development.

Anti-proliferative and anti-tumour effect of active components in donkey milk on A549 human lung cancer cells

“…In addition, lysozyme has other physiological functions, including inactivation of certain viruses, immuno-regulatory activity, antiinflammatory and anti-tumour activity (Ibrahim & Aoki, 2003). Several studies have indicated that lysozyme derived from hen eggwhite, marine bacterium and shark cartilage possesses effective angiogenic inhibition and anti-tumour activities (Jiao et al, 2004;Sava, 1989;Ye, Wang, Chen, Gu, & Sun, 2008). Oral administration of hen egg-white lysozyme to mice bearing B16 melanoma significantly reduced the formation of spontaneous lung metastases (Sava, 1989).…”

LYG1 exerts antitumor function through promoting the activation, proliferation, and function of CD4+ T cells

“…28 Lysozymes have been reported to inhibit tumor growth. [19][20][21][22] Therefore, we performed a series of experiments to evaluate the function and mechanisms of antitumor effect of LYG1. We found that rhLYG1 could significantly suppress the growth of B16 tumors in a dosedependent way.…”

“…[19][20][21][22] To test whether LYG1 could have antitumor functions, B16 graft melanoma model was adopted. B16 tumor cells were inoculated s.c. into B6 mice, and rhLYG1 (diluted in PBS) or PBS (control) was injected i.p.…”

“…20 Marine lysozyme could inhibit angiogenesis and tumor growth. 21 Egg white lysozyme could increase the number of CD8 C T cells in mice bearing MCa mammary carcinoma. 22 Based on these clues, in this study, we have verified the secretion of LYG1, investigated the bacteriolytic and tumorinhibiting function, and explored the mechanism of its antitumor function.…”

Expression, characterization, and antimicrobial ability of T4 lysozyme from methylotrophic yeast Hansenula polymorpha A16

“…They possess antimicrobial activity, inhibit tumor growth and angiogenesis, and may have therapeutic value in antitumor drug development [4]. Furthermore, cloned human, bovine, microbial [5], and hen egg-white [6,7] lysozymes have been effectively used for in situ bio-preservation of foodstuffs.…”