Gene expression profiling of human promyelocytic leukemia HL-60 cell treated by ajoene

Objective: Ajoene, a major compound extracted from crashed garlic, has been shown to have antitumor, antimycotic, antimicrobial, antimutagenic functions in vivo or in vitro and treated as a potential antitumor drug. However, the molecular mechanisms underlying the tumor cytotoxicity of ajoene and even garlic substances are poorly defined. In the present study, we aimed to generate gene expression profiles of HL-60 cell treated by ajoene. Methods: A cDNA microarray presenting 2400 of genes amplified from human leukocyte cDNA library was constructed and the gene expression profiles of HL-60 cell induced by ajoene were generated. Results: After data analysis, 28 differentially expressed genes were identified and sequenced. These genes include 21 known genes and 7 ESTs. Most of the known genes are related to cell apoptosis, such as secretory granule (PRG1), beta-2 microglobulin (B2M), 16S ribosomal RNA gene and ribosomal protein S12. Several genes are related to cell differentiation, including the genes similar to H3 histone and ribosomal protein L31. Northern blot analysis was used to verify and quantify the expression of selected genes. Conclusion: Ajoene can induce HL-60 cell apoptosis significantly and may play a role in differentiation. cDNA microarray technology can be a valuable tool to gain insight into molecular events of pharmacological mechanism of herbal medicine.