Study On Anti-tumor Activity Of Animal-derived Peptide

Malignant tumor has become one of the major causes of global deaths. Atpresent, anti-tumor drugs have high drug efficacy but toixity, poor selectivity,anddrug resistance. Therefore, it is urgent to find efficient, specific and low-toxicanti-tumor drugs in different ways for our tumor treatment. Given the advantages ofpeptides such as relatively simple structure, more clear function, specificity and minorside effects, peptide drug is becoming a hot research in this field.This study focused on a bioactive peptide named LH-7，which was analyzed andselected by a kind of bioinformatics software.We evaluated its anti-tumor activity anddiscussed its anti-tumor machanism through a series of cell experiments in vitro andenhancement of immunologic function experiment in vivo, which had laid thefoundation for its research and development to be a new anti-tumor medicine. themain researches included:Analyzed the inhibitory effect of LH-7on liver cancer cells HepG2by MTTmethod: when LH-7with a concentration of0.01-1.0μmol/L, the inhibition ratepresented concentration dependence; Especially when its concentration is1.0μmol/L,the inhibition rate could achieve up to32.03%. Further using improved MTTmethod detected its effect on the leukemia cells HL-60: it showed a dose and timedependent with concentration range of0.1-10μmol/L and time range of0-72hr; TheIC50was15.4μmol/L after treating on HL-60cells for48h,while8.8μmol/L for72h.Through transmission electron microscopy detection and flow cytometricanalysis,the result suggested that the mechanism of HL-7on inhibition of HL-60cellswas probably realized by inducing apoptosis.As immune regulation also plays an important role in inhibiting tumor, the effectof LH-7on enhancing the immune function of mice showed: LH-7could obviouslypromote the proliferation of mice spleen lymphocyte and improve the vigor of NKcells, which initially demonstrated that LH-7could improve the immune function ofmice. This suggested that the anti-tumor mechanism of LH-7could also come fromindirect anti-tumor effect,such as stimulating the immunocyte activity and protecting immune organs. Observing the anatomical structure of organs and the process of drugadministration, LH-7appeared to be no apparent toxic effect on mice,showingrelatively small side-effects, which laid a foundation for its achievement to beanti-tumor immune peptide drugs.The study on stability of LH-7: LH-7in powder condition showed goodstability and could be stored in4℃and dark condition for long to six months withoutdegradation; While in liquid condition, high temperature and repeated freezing andthawing exerted an bad influence on its stability.Considering the diversity of peptide products and realizability of functional food,this study also confirmed that we could obtain mixture of anti-tumor peptides fromzymolysing animal-based serum. It was expected to eventually get LH-7or peptideswith similar activity to LH-7subsequent to separation and purification.