Multi-drug-resistant cells enriched from chronic myeloid leukemia cells by Doxorubicin possess tumor-initiating-cell properties

J Pharmacol Sci. 2013;122(4):299-304. doi: 10.1254/jphs.13025fp. Epub 2013 Aug 1.

Abstract

Multiple drug resistance (MDR) occurring during chemotherapy is a major obstacle for treatment of cancers using chemotherapeutic drugs; thus, the mechanisms underlying MDR have attracted intensive attention. Many studies have shown that tumor-initiating cells exhibit a chemotherapeutic tolerance characteristic. However, whether the MDR cells possess tumor-initiating cells properties and its underlying mechanisms remain to be fully elucidated. In this study, we utilized a well-established MDR cell line K562/A02 enriched by doxorubicin from K562 cells to determine if the K562/A02 cells possess tumor-initiating properties and investigated its potential molecular mechanisms. We observed that the expressions of Oct4, Sox2, and Nanog, all of which are well-characterized stem cell markers, in K562/A02 cells were elevated in comparison to parental K562 cells; in addition, we found that K562/A02 cells exhibited more potent in vitro and in vivo tumor-initiating properties, as revealed by sphere assay, self-renewal assay, soft agar assay, and animal studies. Furthermore, our data suggest that snail and twist1, two well known transcriptional factors for the epithelial-mesenchymal transition (EMT) program, may be potentially involved in the acquisition of tumor-initiating properties of K562/A02 cells. Thus, our study demonstrates that MDR K562/A02 cells possess tumor-initiating properties, most likely due to the elevated expressions of snail and twist1.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antibiotics, Antineoplastic / pharmacology*
  • Cell Transformation, Neoplastic / drug effects*
  • Cell Transformation, Neoplastic / genetics
  • Doxorubicin / pharmacology*
  • Drug Resistance, Multiple*
  • Drug Resistance, Neoplasm*
  • Homeodomain Proteins / metabolism
  • Humans
  • K562 Cells
  • Leukemia, Myelogenous, Chronic, BCR-ABL Positive / genetics
  • Leukemia, Myelogenous, Chronic, BCR-ABL Positive / pathology*
  • Nanog Homeobox Protein
  • Neoplastic Stem Cells / metabolism
  • Neoplastic Stem Cells / pathology*
  • Nuclear Proteins / metabolism
  • Nuclear Proteins / physiology
  • Octamer Transcription Factor-3 / metabolism
  • SOXB1 Transcription Factors / metabolism
  • Snail Family Transcription Factors
  • Transcription Factors / metabolism
  • Transcription Factors / physiology
  • Twist-Related Protein 1 / metabolism
  • Twist-Related Protein 1 / physiology

Substances

  • Antibiotics, Antineoplastic
  • Homeodomain Proteins
  • NANOG protein, human
  • Nanog Homeobox Protein
  • Nuclear Proteins
  • Octamer Transcription Factor-3
  • POU5F1 protein, human
  • SOX2 protein, human
  • SOXB1 Transcription Factors
  • Snail Family Transcription Factors
  • TWIST1 protein, human
  • Transcription Factors
  • Twist-Related Protein 1
  • Doxorubicin