Tags

Type your tag names separated by a space and hit enter

Overexpression of Bcl-2 or Bcl-xL inhibits Ara-C-induced CPP32/Yama protease activity and apoptosis of human acute myelogenous leukemia HL-60 cells.
Cancer Res. 1996 Oct 15; 56(20):4743-8.CR

Abstract

Ara-C has been shown to induce apoptosis of human acute myelogenous leukemia HL-60 cells. The DNA repair enzyme poly(ADP-ribose) polymerase (PARP) is known to be degraded during apoptosis. PARP as a substrate is cleaved by the Yama protease, encoded by the CPP32beta/Yama gene. Yama belongs to the interleukin 1beta converting enzyme/ced-3 family of cysteine proteases that are activated as a cascade, producing proteolytic cleavage of specific substrates that results in the morphological and biochemical features of apoptosis. In the present studies, we determined the effect of high intracellular levels of the antiapoptosis Bcl-2 or Bcl-xL protein on Yama protease activation and PARP degradation during Ara-C-induced apoptosis. For this, we utilized HL-60/Bcl-2, HL-60/Bcl-xL, or control HL-60/neo cells, which were created by transfection of the cDNA of the bcl-2, bcl-xL, or the neomycin-resistant genes, respectively. As compared to HL-60/neo, HL-60/Bcl-2 and HL-60/Bcl-xL cells have 5-fold greater expression of Bcl-2 and Bcl-xL, respectively. However, these cell lines have similar levels of p32Yama and PARP. Treatment with 10 or 100 microM Ara-C for 4 h produced DNA fragmentation and morphological features of apoptosis in HL-60/neo cells. This was associated with the cleavage and activation of p32Yama and PARP degradation but not with the induction of Yama mRNA. In contrast, in HL-60/Bcl-2 and HL-60/ Bcl-xL cells, Ara-C-induced p32Yama activation by its cleavage, PARP degradation and apoptosis were significantly inhibited. High Bcl-2 and Bcl-xL levels in these cells also inhibited Yama protease activity, PARP degradation, and apoptosis due to clinically relevant concentrations of etoposide and mitoxantrone. These results suggest that the activation of the Yama protease and PARP degradation are involved in Ara-C-, etoposide-, or mitoxantrone-induced apoptosis. In addition, they suggest that Bcl-2 and Bcl-xL antagonize drug-induced apoptosis by a mechanism that interferes in the activity of a key cysteine protease that is involved in the execution of apoptosis.

Authors+Show Affiliations

Department of Medicine, Winship Cancer Center, Emory University School of Medicine, Atlanta, Georgia 30322, USA.No affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info available

Pub Type(s)

Journal Article

Language

eng

PubMed ID

8840993

Citation

Ibrado, A M., et al. "Overexpression of Bcl-2 or Bcl-xL Inhibits Ara-C-induced CPP32/Yama Protease Activity and Apoptosis of Human Acute Myelogenous Leukemia HL-60 Cells." Cancer Research, vol. 56, no. 20, 1996, pp. 4743-8.
Ibrado AM, Huang Y, Fang G, et al. Overexpression of Bcl-2 or Bcl-xL inhibits Ara-C-induced CPP32/Yama protease activity and apoptosis of human acute myelogenous leukemia HL-60 cells. Cancer Res. 1996;56(20):4743-8.
Ibrado, A. M., Huang, Y., Fang, G., Liu, L., & Bhalla, K. (1996). Overexpression of Bcl-2 or Bcl-xL inhibits Ara-C-induced CPP32/Yama protease activity and apoptosis of human acute myelogenous leukemia HL-60 cells. Cancer Research, 56(20), 4743-8.
Ibrado AM, et al. Overexpression of Bcl-2 or Bcl-xL Inhibits Ara-C-induced CPP32/Yama Protease Activity and Apoptosis of Human Acute Myelogenous Leukemia HL-60 Cells. Cancer Res. 1996 Oct 15;56(20):4743-8. PubMed PMID: 8840993.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Overexpression of Bcl-2 or Bcl-xL inhibits Ara-C-induced CPP32/Yama protease activity and apoptosis of human acute myelogenous leukemia HL-60 cells. AU - Ibrado,A M, AU - Huang,Y, AU - Fang,G, AU - Liu,L, AU - Bhalla,K, PY - 1996/10/15/pubmed PY - 1996/10/15/medline PY - 1996/10/15/entrez SP - 4743 EP - 8 JF - Cancer research JO - Cancer Res VL - 56 IS - 20 N2 - Ara-C has been shown to induce apoptosis of human acute myelogenous leukemia HL-60 cells. The DNA repair enzyme poly(ADP-ribose) polymerase (PARP) is known to be degraded during apoptosis. PARP as a substrate is cleaved by the Yama protease, encoded by the CPP32beta/Yama gene. Yama belongs to the interleukin 1beta converting enzyme/ced-3 family of cysteine proteases that are activated as a cascade, producing proteolytic cleavage of specific substrates that results in the morphological and biochemical features of apoptosis. In the present studies, we determined the effect of high intracellular levels of the antiapoptosis Bcl-2 or Bcl-xL protein on Yama protease activation and PARP degradation during Ara-C-induced apoptosis. For this, we utilized HL-60/Bcl-2, HL-60/Bcl-xL, or control HL-60/neo cells, which were created by transfection of the cDNA of the bcl-2, bcl-xL, or the neomycin-resistant genes, respectively. As compared to HL-60/neo, HL-60/Bcl-2 and HL-60/Bcl-xL cells have 5-fold greater expression of Bcl-2 and Bcl-xL, respectively. However, these cell lines have similar levels of p32Yama and PARP. Treatment with 10 or 100 microM Ara-C for 4 h produced DNA fragmentation and morphological features of apoptosis in HL-60/neo cells. This was associated with the cleavage and activation of p32Yama and PARP degradation but not with the induction of Yama mRNA. In contrast, in HL-60/Bcl-2 and HL-60/ Bcl-xL cells, Ara-C-induced p32Yama activation by its cleavage, PARP degradation and apoptosis were significantly inhibited. High Bcl-2 and Bcl-xL levels in these cells also inhibited Yama protease activity, PARP degradation, and apoptosis due to clinically relevant concentrations of etoposide and mitoxantrone. These results suggest that the activation of the Yama protease and PARP degradation are involved in Ara-C-, etoposide-, or mitoxantrone-induced apoptosis. In addition, they suggest that Bcl-2 and Bcl-xL antagonize drug-induced apoptosis by a mechanism that interferes in the activity of a key cysteine protease that is involved in the execution of apoptosis. SN - 0008-5472 UR - https://www.unboundmedicine.com/medline/citation/8840993/Overexpression_of_Bcl_2_or_Bcl_xL_inhibits_Ara_C_induced_CPP32/Yama_protease_activity_and_apoptosis_of_human_acute_myelogenous_leukemia_HL_60_cells_ L2 - http://cancerres.aacrjournals.org/cgi/pmidlookup?view=long&pmid=8840993 DB - PRIME DP - Unbound Medicine ER -