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DNA damage induced by oridonin involves cell cycle arrest at G2/M phase in human MCF-7 cells

Tao Zhang1, Yan Tan, Rui Zhao

  • 1Central Research Laboratory, the First Affiliated Hospital of Jilin University, Changchun, China ; School of Basic Medical Sciences, Jiamusi University, No. 148 Xuefu Street, Jiamusi City, Heilongjiang Province, China.

Contemporary Oncology (Poznan, Poland)
|June 22, 2013
PubMed
Abstract

Insights

Oridonin inhibits breast cancer cell growth and causes DNA damage, leading to cell cycle arrest. This occurs via ATM/CHK2 activation and subsequent p53 signaling, highlighting oridonin

Area of Science:

  • Molecular Biology
  • Cancer Research
  • Pharmacology

Background:

  • Oridonin is a natural compound with potential anti-cancer properties.
  • Understanding the mechanisms of oridonin's action is crucial for its therapeutic development.
  • MCF-7 cells are a commonly used model for human breast cancer research.

Purpose of the Study:

  • To investigate how oridonin inhibits cell growth in MCF-7 breast cancer cells.
  • To elucidate the mechanisms by which oridonin induces DNA damage.
  • To explore the role of key proteins in the DNA damage response pathway.

Main Methods:

  • Cytotoxicity was assessed using MTT assays.
  • Cell cycle distribution was analyzed via flow cytometry.
  • Protein expression (P-ATM, P-CHK2, γH2AX, P-P53) was determined by Western blot and immunofluorescence.
  • DNA fragmentation was evaluated using the comet assay.

Main Results:

  • Oridonin demonstrated dose- and time-dependent inhibition of MCF-7 cell growth.
  • Oridonin induced G2/M phase cell cycle arrest and significant DNA damage.
  • Increased expression of P-ATM, P-CHK2, γH2AX, and P-P53 proteins was observed.

Conclusions:

  • Oridonin-induced DNA damage triggers a p53-mediated G2/M cell cycle arrest in MCF-7 cells.
  • The mechanism involves CHK2 activation by ATM protein kinase, initiated by oridonin.
  • These findings provide insight into oridonin's anti-cancer effects.
Keywords:
ATMCHK2apoptosiscell cycleoridoninp53

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