Gene chip technology was used to determine the gene expression profiles in apoptotic K562 cells induced by homoharringtonine. The expression of forty-four mRNAs was found to be changed significantly were identified after screening with a gene chip capable of detecting 14,218 different human mRNA species simultaneously. Of these genes, 17 were up-regulated and 27 were down-regulated. Most of them were found to be related to apoptosis, oncogenes, or tumor suppression. Several genes with altered gene expression, such as human transforming growth factor-beta inducible early protein gene (TIEG), vitamin D3 upregulated protein 1 gene (VDUP1), RNA binding motif protein 4 gene (RBM4) and v-myc myelocytomatosis viral oncogene homolog (C-MYC), were confirmed by Northern blot analysis. According to the dynamic gene expression pattern in these apoptotic cells, the activated transforming growth factor-beta and tumor necrosis factor signaling pathways play an important role in homoharringtonine-induced apoptosis. TIEG was significantly altered after apoptosis induction, it should be critical for apoptosis signal transmission.