Daunorubicin-induced variations in gene transcription: commitment to proliferation arrest, senescence and apoptosis

Abstract

We used a human cDNA macroarray containing various oncogenes and tumour suppressor genes to assess gene expression profiles in early-passage Jurkat T lymphocytes treated with clinically relevant concentrations of the antitumour antibiotic daunorubicin. Several oncogenes and tumour suppressor genes were either up- or down-regulated depending on the daunorubicin concentration used. The expression levels of some of these genes were confirmed by semi-quantitative reverse transcriptase-PCR. We also compared the changes in cell-cycle distribution and the apoptotic morphological characteristics of the cells treated with daunorubicin, using flow cytometry and fluorescence microscopy. Exposure to 182 nM daunorubicin (its IC(75) in Jurkat T cells: where IC(75) is the drug concentration that inhibits growth by 75%) resulted in cell-cycle arrest in G(1) and almost immediate apoptosis. In contrast, decreasing the drug concentration to 91 nM (close to the IC(50)) caused G(2) arrest and cell senescence-like growth arrest, whereas features of apoptosis and necrosis appeared only after longer incubation times. Gene expression profiles, cell-cycle distribution, the presence of DNA damage and the time-dependent response of Jurkat T cells to cell death were correlated clearly. The general behaviour of the genes suggests that cell-cycle arrest and cell death follow distinct pathways depending on drug concentration.

Gefitinib induces premature senescence in non-small cell lung cancer cells with or without EGFR gene mutation

“…In PC-9 cells, gefitinib treatment did not induce the up-regulation of p16 INK4A . It seems to be that induction of p21 WAF/Cip1 rather than p16 INK4A dominantly led to G 1 arrest in this cell line, as reported by Mansilla et al and te Poele et al (7,18).…”

“…Generally, induction of senescence is defined by up-regulation of CDK-inhibitors and activation of p53 (6)(7)(8). In PC-9 cells, immediate and temporal up-regulation of p21 WAF1/Cip1 followed by temporal up-regulation of p27 Kip1 was also observed with gefitinib treatment (Fig.…”

“…The DNA damage response triggered by other cellular stresses, including exposure to chemotherapeutic agents can also induce senescence, often termed premature senescence (15)(16)(17). Cisplatin, hydroxyurea, irinotecan, daunorubicin and retinoic acid have also been reported to induce senescence in various tumor cell lines (6)(7)(8)18). Although gefitinib is not known as a DNA damaging agent, it might be possible that gefitinib modulated the repair of DNA by involving the DNA-dependent protein kinase (DNA-PK) pathway (19).…”

“…To explain clinically observed gefitinib-induced rapid and tremendous tumor regression, contribution of other additional mechanism of cell death was supposed. Senescence has been shown to play a central role in anti-tumor effect induced by different classes of anti-cancer agents and ionising radiation (6)(7)(8). In this study, we examined whether gefitinib could induce cellular senescence in gefitinib-sensitive NSCLC cells.…”

Susceptibility loci involved in cisplatin-induced cytotoxicity and apoptosis

“…Masquelier et al [29] demonstrated differences in the induction of apoptosis depending upon daunorubicin concentration, with higher doses correlating to more rapid caspase-3 induction and DNA fragmentation in leukemic cells. In another study, upregulation or downregulation of oncogenes and tumor suppressor genes depended on the concentration of drug used [30]. The IC 50 phenotype is thought to be representative of the cytotoxic curve for each cell line; however, no linkage peaks greater than LOD of 1.5 were found for this phenotype.…”