Antitumor effects and cell selectivity of temporin-1CEa, an antimicrobial peptide from the skin secretions of the Chinese brown frog (Rana chensinensis)

• Published in: Biochimie 2012-02, Vol.94 (2), p.434-441
• Main Authors: Wang, Che, Li, Hui-Bing, Li, Song, Tian, Li-Li, Shang, De-Jing
• Format: Article
• Language: English
• Subjects: Amino Acid Sequence; Animals; Antimicrobial Cationic Peptides - chemical synthesis; Antimicrobial Cationic Peptides - isolation & purification; Antimicrobial Cationic Peptides - pharmacology; Antimicrobial peptide; Antineoplastic Agents - chemical synthesis; Antineoplastic Agents - isolation & purification; Antineoplastic Agents - pharmacology; Antitumor; Breast Neoplasms - drug therapy; Breast Neoplasms - metabolism; Breast Neoplasms - pathology; Carcinoma - drug therapy; Carcinoma - metabolism; Carcinoma - pathology; Cell Line, Tumor; Cell selectivity; Cell Survival - drug effects; China; DNA, Complementary - genetics; Erythrocytes - drug effects; Female; Human Umbilical Vein Endothelial Cells; Humans; Molecular Sequence Data; Protein Isoforms - chemical synthesis; Protein Isoforms - isolation & purification; Protein Isoforms - pharmacology; Proteins - chemical synthesis; Proteins - isolation & purification; Proteins - pharmacology; Rana chensinensis; Ranidae - physiology; Sequence Homology, Amino Acid; Skin - metabolism; Skin - secretion; Temporin-1CEa
• ISSN: 0300-9084; 1638-6183
• DOI: 10.1016/j.biochi.2011.08.011

Many antimicrobial peptides from amphibian exhibit additional anticancer properties due to a similar mechanism of action at both bacterial and cancer cells. We have previously reported the cDNA sequence of the antimicrobial peptide temporin-1CEa precursor cloned from the Chinese brown frog Rana chensinensis. In this study, we purified, synthesized and structurally characterized temporin-1CEa from the skin secretions of R. chensinensis. The cytotoxicity and cell selectivity of temporin-1CEa were further examined on twelve human carcinoma cell lines and on normal human umbilical vein smooth muscle cells (HUVSMCs). Our results indicated that temporin-1CEa has the amino acid sequence of FVDLKKIANIINSIF-NH2, and exhibits 50–56% identity with temporin family peptides from other frog species. The CD spectra for temporin-1CEa adopted a well-defined α-helical structure in 50% TFE/water solution. The results of MTT assay showed that temporin-1CEa exhibits cytotoxicity to all tested cancer cell lines in a concentration-dependent manner, being MCF-7 cells the most sensitive. Moreover, temporin-1CEa had lower hemolytic effect to human erythrocytes and had no significant cytotoxicity to normal HUVSMCs at concentrations showed potent antitumor activity. In summary, temporin-1CEa, an amphiphilic α-helical cationic peptide, may represent a novel anticancer agent for breast cancer therapy, considering its cancer cell selectivity and relatively lower cytotoxicity to normal cells. ► A novel amphiphilic antimicrobial peptide, temporin-1CEa was purified from Rana chensinensis. ► The percentage of α-helix content of the cationic peptide in 50% TFE was 87.59%. ► Temporin-1CEa exhibited significant cytotoxicity on 12 human carcinoma cell lines. ► Temporin-1CEa did not exhibit significant cytotoxic effects on nontumorigenic cells.