**The Cytotoxic, Antimicrobial and Anticancer Properties of the Antimicrobial Peptide Nisin Z Alone and in Combination with Conventional Treatments of the Antimicrobial Peptide Nisin Z Alone and in Combination with Conventional Treatments**

**The Cytotoxic, Antimicrobial and Anticancer Properties** 

DOI: 10.5772/intechopen.71927

Angélique Lewies, Lissinda H. Du Plessis and Johannes F. Wentzel Johannes F. Wentzel Additional information is available at the end of the chapter

Angélique Lewies, Lissinda H. Du Plessis and

Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/intechopen.71927

#### **Abstract**

[41] Hamano R, Wu X, Wang Y, Oppenheim JJ, Chen X. Characterization of MT-2 cells as a human regulatory T cell-like cell line. Cellular & Molecular Immunology. 2015;**12**:780-

[42] Ying C, Maeda M, Nishimura Y, Kumagai-Takei N, Hayashi H, Matsuzaki H, Lee S, Yoshitome K, Yamamoto S, Hatayama T, Otsuki T. Enhancement of regulatory T celllike suppressive function in MT-2 by long-term and low-dose exposure to asbestos.

[43] Lee S, Matsuzaki H, Maeda M, Yamamoto S, Kumagai-Takei N, Hatayama T, Ikeda M, Yoshitome K, Nishimura Y, Otsuki T. Accelerated cell cycle progression of human regulatory T cell-like cell line caused by continuous exposure to asbestos fibers. International

[44] Otsuki T, Matsuzaki H, Lee S, Kumagai-Takei N, Yamamoto S, Hatayama T, Yoshitome K, Nishimura Y. Environmental factors and human health: Fibrous and particulate substance-induced immunological disorders and construction of a health-promoting living environment. Environmental Health and Preventive Medicine. 2016;**21**:71-81. DOI:

[45] Matsuzaki H, Maeda M, Lee S, Nishimura Y, Kumagai-Takei N, Hayashi H, Yamamoto S, Hatayama T, Kojima Y, Tabata R, Kishimoto T, Hiratsuka J, Otsuki T. Asbestos-induced cellular and molecular alteration of immunocompetent cells and their relationship with chronic inflammation and carcinogenesis. Journal of Biomedicine & Biotechnology.

[46] Kumagai-Takei N, Maeda M, Chen Y, Matsuzaki H, Lee S, Nishimura Y, Hiratsuka J, Otsuki T. Asbestos induces reduction of tumor immunity. Clinical & Developmental

Toxicology. 2015;**338**:86-94. DOI: 10.1016/j.tox.2015.10.005

Journal of Oncology. 2017;**50**:66-74. DOI: 10.3892/ijo.2016.3776

782. DOI: 10.1038/cmi.2014.123

20 Cytotoxicity

10.1007/s12199-015-0499-6

2012;**2012**:492608. DOI: 10.1155/2012/492608

Immunology. 2011;**2011**:481439. DOI: 10.1155/2011/481439

Nisin is an antimicrobial peptide commonly used as a food preservative since 1969. This peptide has potent antimicrobial activity against several Gram-positive bacterial strains, including clinically important and resistant pathogens. The combination of nisin with conventional antibiotics has been shown to improve the antimicrobial activity of these antibiotic agents. Apart from the antimicrobial properties of nisin, this AMP also displays promising anticancer potential towards several types of malignancies. The nisin Z variant is able to induce selective cytotoxicity in melanoma cells compared to non-malignant cells. It was shown that nisin Z disrupts the cell membrane integrity of melanoma cells and that cytotoxicity is likely due to the activation of an apoptotic pathway. In addition, when used in combination with the conventional chemotherapeutic agents, nisin Z has the potential to enhance the cytotoxicity of these chemotherapeutic agents against cultured melanoma cells. Nisin Z has great potential for clinical application considering its low cytotoxicity to non-malignant cells and its effectiveness against Gram-positive bacterial strains and certain cancers.

**Keywords:** melanoma, antimicrobial peptide nisin Z, combination therapy, selective cancer cytotoxicity, chemotherapeutic agents, antibiotic resistance

### **1. Introduction**

Antimicrobial peptides (AMPs) are produced by all known living species and exhibit direct microbial killing activity while also playing an important role in the innate immune system [1]. This diverse group of peptides is found in all living species and may be promising alternatives

Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. © 2018 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

© 2016 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons

or serves as additives to current antibiotics [2–4]. Many of the more than 2000 known AMPs have been demonstrated to exhibit broad-spectrum antibacterial activity [5], and bacteria are less likely to develop resistance to these peptides compared to conventional antibiotics [6, 7].

In Gram-positive bacteria, nisin exhibits a dual mode of action by binding to lipid II on the bacterial membrane resulting in the inhibition of cell wall synthesis and the formation of pores in the bacterial cell membrane [23]. The antimicrobial effects of nisin Z against Gramnegative bacteria are largely inadequate. However, the activity towards Gram-negative bacteria can be improved by using ethylenediaminetetraacetic acid (EDTA) and the non-ionic

The Cytotoxic, Antimicrobial and Anticancer Properties of the Antimicrobial Peptide Nisin Z…

http://dx.doi.org/10.5772/intechopen.71927

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The glycopeptide antibiotic, vancomycin, also binds to lipid II to inhibit cell wall synthesis, albeit at a different amino acid moiety. Vancomycin is one of the last line treatments against several Gram-positive antibiotic-resistant bacteria including methicillin-resistant *Staphylococcus aureus* (MRSA) [26, 27]. Disturbingly, clinical variants of MRSA have been isolated of which the lipid II pentapeptide have mutated to acquire resistant to vancomycin. These strains contain the *vanA*-type gene cluster where the terminal D-Ala has been changed to D-Lactate in the lipid II pentapeptide [28]. Due to its different binding motif, nisin remains active against the *vanA*-type resistant strains [29]. This shows the potential of nisin to bolster the antimicrobial defences against antibiotic-resistant bacterial strains. Nisin has a promising potential for clinical application with its GRAS status and approval by both the FDA and WHO, considering its low cytotoxicity and the fact that it is considered safe for human consumption. Currently, it is employed as a food preservative in nearly 50 countries to guard food against spoilage resulting from pathogens such as *Staphylococcus aureus, Listeria monocytogenes*, and *Clostridium botulinum* [30]. In addition, nisin has also been demonstrated to possess antibacterial activity against several clinically

**Figure 1.** Minimum inhibitory concentrations (MIC) of nisin Z for Gram-positive and Gram-negative bacterial strains.

The effect of EDTA (200 μM) on the MIC of *E. coli* is also demonstrated.

surfactant Tween®80 [24, 25] (**Figure 1**).

The lantibiotic nisin, produced by *Lactococcus lactis*, has promising potential for clinical application with its *Generally Regarded as Safe* (GRAS) status. This AMP was approved by the World Health Organisation (WHO) in 1969 and the US Federal Food and Drug Administration (FDA) in 1988 for the use as a food preservative [8]. Despite being extensively utilised for food preservation for nearly 50 years, there is very little indication of resistant mutants arising in food products treated with this AMP [8, 9].

Nisin is primarily used for its antibacterial activity. However, AMPs, and especially bacteriocins, display selectivity towards cancer cells [10]. Due to the toxicity associated with many conventional chemotherapeutic agents, as well as the development of chemotherapy resistance [11–13], there is a need for the development of novel anti-cancer therapies. Furthermore, to overcome chemotherapy resistance, the efficacy of chemotherapeutic agents can be enhanced by the co-administration of multi-functional agents to achieve synergistic interactions [14, 15]. The ability of nisin to increase the activity of the chemotherapeutic drug doxorubicin was investigated *in vivo* by Preet and co-workers. Nisin, when used in combination with doxorubicin, enhanced the anti-cancer activities of doxorubicin. Apoptosis could be detected upon treatment of mice with induced skin carcinogenesis. However, the exact mechanism by which nisin exerts its anti-cancer activities was not known [16].
