The Studies On Antitumor Activities Of A Small Molecular Tripeptide LYRM03

The etiologic complexity and resistance of malignant tumor, one of themajor health hazards, lead to great difficulty on the clarification of itsmechanism and drug therapy. In this paper, the effects of LYRM03, a smalltripeptide compound, on inhibitory activities of proliferation, migration andaminopeptidase N of tumor cells, the combination of LYRM03and tumorcells, and the tissue distribution of LYRM03were studied. The aim of thispaper was to discover the characteristics of the compound and to providemeaningful data and direction for further research.In this study, the proliferation inhibitions of a variety of tumor cell lines,such as MCF-7、HL60、PANC-1、K562、Hela and U937were screenedby the MTT assay. LYRM03had the different proliferation inhibition onthese cells. The inhibition rates of500μmol/L LYRM03and Bestation were100.0%on cell line HL60and IC50of LYRM03and Bestatin was9.8μmol/L and1.1μmol/L. The proliferation inhibitions of LYRM03onMCF-7and K562were higher than that of Bestatin and the inhibition ratesof500μmol/L LYRM03on the two cells were52.7%and53.6%. Themigration inhibitions of a variety of tumor cell lines were detected byScratch method and Transwell method. The migration inhibition ofLYRM03was better than that of Bestatin on Hela、PANC-1、MDA,ASPC-1and MCF-7. The activities of inhibitions on a variety of cell surfaceaminopeptidase N were detected.The IC50of LYRM03on cell surface aminopeptidase N of PANC-1、MCF-7、Hela、HepG2、ASPC-1、HL7702、A549、HL60、BEL7402、MDA were4.6μmol/L,11.4μmol/L,13.8μmol/L,13.0μmol/L,6.2μmol/L,22.3μmol/L,17.7μmol/L,19.8μmol/L,22.0μmol/L,30.1μmol/L, which were higher than the IC50ofBestatin. LYRM03and Bestatin were labeled with fluoresceinisothiocyanate（FITC）and fluorescein-labeled compounds ofFITC-LYRM03and FITC-Bestatin were purified. The yield were10.8%and8.1%.The binding activities to tumor cells and the activities ofaminopeptidase N were in accordance and the binding activities werehighest on the cell MCF-7. Compound LYRM03was distributed in thetissuses of kidney, liver and uterus more than that of Bestatin in the course ofnude mice’s metabolism.