Low‐dose doxorubicin‐induced necrosis in Jurkat cells and its acceleration and conversion to apoptosis by antioxidants

Abstract

Summary. We treated rapidly growing Jurkat cells with 40 nmol/l of doxorubicin for 72 h. After 36 h, the G2‐arrested cells became larger and some of them started endoreplication. Nuclear staining with Hoechst 33342 combined with propidium iodide (PI) exclusion revealed that about 90% of the cells were necrotic at 72 h, although apoptotic cells accounted for only 8%. Incubation with 40 nmol/l of aclarubicin or cytosine β‐d‐arabinofuranoside for 60 h induced necrosis both in Jurkat and ml‐1 cells. Pre‐necrotic Jurkat cells incubated with 40 nmol/l of doxorubicin had much higher intracellular reactive oxygen species (ROS) levels than pre‐apoptotic ones. Addition of Tempol or Desferal accelerated doxorubicin‐induced necrosis and partially converted it into apoptosis. Both antioxidants reduced surviving colony numbers of prenecrotic Jurkat cells. n‐acetyl‐l‐cysteine had little effect on the apoptotic conversion but profoundly accelerated necrosis. Because an apoptosis‐resistant Jurkat subclone was also refractory to doxorubicin‐induced necrosis, apoptosis and necrosis might share some common pathways. Low‐dose doxorubicin increased micronuclei‐positive cell percentages and also suppressed high‐dose doxorubicin‐induced apoptosis in Jurkat and ml‐1 cells. Some of the prenecrotic cells, therefore, might survive and obtain genomic instability. Antioxidants may be useful to suppress, at least to some extent, this vicious consequence.

Hsp90-inhibitor geldanamycin abrogates G2 arrest in p53-negative leukemia cell lines through the depletion of Chk1

“…We previously showed that treatment with 50 nM doxorubicin for 48 h induced necrosis in most Jurkat cells without apparent apoptosis (Sugimoto et al, 2002). In this study, addition of 100 nM GM at 24 h made more than 40% of doxorubicin-treated Jurkat cells TUNEL positive ( Figure 6a).…”

“…Clonal cell culture Methylcellulose cell culture was carried out in a 35-mm suspension culture dish (Nalge Nunc, Rochester, NY, USA) using Methocult H4230 (Stem Cell Technologies, Vancouver, BC, Canada) essentially as described previously (Sugimoto et al, 2002). Rapidly growing Jurkat and HL-60 cells were treated with 50 nM doxorubicin or with 1.2 mM of ICRF-193 for 24 h, and further incubated in the presence or absence of 100 nM GM for additional 24 h. Then living cell numbers were counted by trypan blue exclusion test, and 1 Â 10 4 cells were plated for each condition as triplicate.…”

Effects of tempol and redox-cycling nitroxides in models of oxidative stress

“…Tempol potentiated the cell death and/or apoptosis, and upregulated p22 protein expression (Ravizza et al, 2004b) in Jurkat tumor cells (Sugimoto et al, 2002), human Burkitt lymphoma cells (Shacter et al, 2000) and colon cancer cells (Ravizza et al, 2004b). Tempol reduced ROS and diminished toxicity of the chemotherapeutic agents doxorubicin, cisplatin, AraC or VP-16 (Czepas et al, 2008).…”

Black Rice Bran Extracts and Fractions Containing Cyanidin 3-glucoside and Peonidin 3-glucoside Induce Apoptosis in Human Cervical Cancer Cells

“…Sugimoto et al (2002) also reported that low-dose of doxorubicin (40 nmol/L) induced 90% of necrosis and 8% of apoptosis in Jurkat cells. Furthermore, the percentages of apoptosis induction by fractions F2 and F4 are higher than F3 and F5.…”