The pterocarpanquinone LQB‑118 compound induces apoptosis of cytarabine‑resistant acute myeloid leukemia cells.

Abstract

Acute myeloid leukemia (AML) is a complex hematological disorder characterized by blockage of differentiation and high proliferation rates of myeloid progenitors. Anthracycline and cytarabine‑based therapy has remained the standard treatment for AML over the last four decades. Although this treatment strategy has increased survival rates, patients often develop resistance to these drugs. Despite efforts to understand the mechanisms underlying cytarabine resistance, there have been few advances in the field. The present study developed an in vitro AML cell line model resistant to cytarabine (HL‑60R), and identified chromosomal aberrations by karyotype evaluation and potential molecular mechanisms underlying chemoresistance. Cytarabine decreased cell viability, as determined by MTT assay, and induced cell death and cell cycle arrest in the parental HL‑60 cell line, as revealed by Annexin V/propidium iodide (PI) staining and PI DNA incorporation, respectively, whereas no change was observed in the HL‑60R cell line. In addition, the HL‑60R cell line exhibited a higher tumorigenic capacity in vivo compared with the parental cell line. Notably, no reduction in tumor volume was detected in mice treated with cytarabine and inoculated with HL‑60R cells. In addition, western blotting revealed that the protein expression levels of Bcl‑2, X‑linked inhibitor of apoptosis protein (XIAP) and c‑Myc were upregulated in HL‑60R cells compared with those in HL‑60 cells, along with predominant nuclear localization of the p50 and p65 subunits of NF‑κB in HL‑60R cells. Furthermore, the antitumor effect of LQB‑118 pterocarpanquinone was investigated; this compound induced apoptosis, a reduction in cell viability and a decrease in XIAP expression in cytarabine‑resistant cells. Taken together, these data indicated that acquired cytarabine resistance in AML was a multifactorial process, involving chromosomal aberrations, and differential expression of apoptosis and cell proliferation signaling pathways. Furthermore, LQB‑118 could be a potential alternative therapeutic approach to treat cytarabine‑resistant leukemia cells.

• Authors: Thaís Hancio, Luciano Mazzoccoli, Gustavo Guimarães, Marcela Robaina, Bruna Dos Santos Mendonça, Gabriela Nestal De Moraes, Barbara Da Costa Reis Monte-Mor, Luciana Mayumi Gutiyama, Luíze Otero De Carvalho, Chaquip Daher Netto, Paulo R R Costa, Fernanda Costas Casal De Faria, Raquel Ciuvalschi Maia
• Journal: International journal of oncology (Int J Oncol) Vol. 58 Issue 6 (06 2021) ISSN: 1791-2423 [Electronic] Greece
• PMID: 33786613 (Publication Type: Journal Article)

Chemical References

• LQB 118
• Naphthoquinones
• Pterocarpans
• X-Linked Inhibitor of Apoptosis Protein
• XIAP protein, human
• Cytarabine

Topics

• Animals
• Apoptosis (drug effects, genetics)
• Chromosome Aberrations
• Cytarabine (therapeutic use)
• Drug Resistance, Neoplasm (genetics)
• Gene Expression Regulation, Neoplastic (drug effects)
• HL-60 Cells
• Humans
• Leukemia, Myeloid, Acute (drug therapy, genetics, pathology)
• Male
• Mice
• Naphthoquinones (pharmacology, therapeutic use)
• Pterocarpans (pharmacology, therapeutic use)
• X-Linked Inhibitor of Apoptosis Protein (genetics)
• Xenograft Model Antitumor Assays