E2F1-mediated DNA damage is implicated in 8-Cl-adenosine-induced chromosome missegregation and apoptosis in human

Yu-Ying Han1, Zhe Zhou, Ji-Xiang Cao

  • 1Department of Biochemistry and Molecular Biology, Capital Medical University, You An Men 8, Beijing, 100069, People's Republic of China.

Insights

8-chloro-adenosine (8-Cl-Ado) induces DNA damage and apoptosis in lung cancer cells by accumulating E2F1. This E2F1-mediated damage, especially during mitosis, contributes to cancer cell death and proliferation inhibition.

Area of Science:

  • Molecular Biology
  • Cancer Research
  • Cell Biology

Background:

  • E2F1's role in DNA double-stranded breaks (DSBs) and tetraploidy is known, but its function in mitotic catastrophe remains unclear.
  • Previous research demonstrated that 8-chloro-adenosine (8-Cl-Ado) induces DSBs and aberrant mitosis in human lung cancer cells, leading to delayed apoptosis.

Purpose of the Study:

  • To investigate the role of E2F1 in 8-chloro-adenosine (8-Cl-Ado)-induced mitotic catastrophe and apoptosis in human lung cancer cells.
  • To elucidate the mechanism by which E2F1 contributes to DNA damage and cell death following 8-Cl-Ado treatment.

Main Methods:

  • Utilized human lung cancer H1299 cells.
  • Analyzed E2F1 accumulation and DNA damage in response to 8-Cl-Ado.
  • Investigated the effects of E2F1 silencing and overexpression on 8-Cl-Ado-induced DNA damage, mitotic aberrations, and apoptosis.
  • Observed mitotic spindle morphology and chromosome segregation.

Main Results:

  • 8-Cl-Ado treatment led to E2F1 accumulation, which in turn caused DNA damage, particularly in M-phase cells.
  • Silencing E2F1 reduced 8-Cl-Ado-induced DNA DSBs and mitigated E2F1-mediated mitotic DNA damage.
  • Overexpression of E2F1 enhanced 8-Cl-Ado-induced apoptosis and resulted in aberrant mitotic spindles and chromosome segregation errors.
  • 8-Cl-Ado exposure, with or without E2F1 overexpression, caused chromosome missegregation.

Conclusions:

  • E2F1-mediated DNA damage, especially mitotic DNA damage, is a significant component of 8-Cl-Ado-induced cellular damage.
  • E2F1 plays a crucial role in 8-Cl-Ado-induced mitotic catastrophe and delayed apoptosis in lung cancer cells.
  • The induction of E2F1 by 8-Cl-Ado may contribute to the drug's ability to inhibit cancer cell proliferation.

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