Related Experiment Video

Updated: May 31, 2026

Pre-Conditioning the Airways of Mice with Bleomycin Increases the Efficiency of Orthotopic Lung Cancer Cell Engraftment
09:02

Pre-Conditioning the Airways of Mice with Bleomycin Increases the Efficiency of Orthotopic Lung Cancer Cell Engraftment

Published on: June 28, 2018

Human telomeric DNA sequences are a major target for the antitumour drug bleomycin

Trung V Nguyen1, Vincent Murray

  • 1School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW 2052, Australia.

Journal of Biological Inorganic Chemistry : JBIC : a Publication of the Society of Biological Inorganic Chemistry
|July 16, 2011
PubMed

Insights

Bleomycin, a cancer drug, preferentially damages human telomeric DNA sequences. This finding highlights telomeres as a significant target for bleomycin activity in cancer therapy.

Area of Science:

  • Molecular Biology
  • Cancer Therapeutics
  • Genetics

Background:

  • Bleomycin is a chemotherapy agent used to treat various cancers.
  • Understanding its DNA sequence specificity is crucial for optimizing its therapeutic use and minimizing side effects.
  • Telomeric DNA sequences, located at the ends of chromosomes, play roles in cellular aging and cancer.

Purpose of the Study:

  • To investigate the DNA sequence specificity of bleomycin.
  • To compare bleomycin's interaction with human telomeric DNA versus non-telomeric DNA.
  • To identify primary sites of bleomycin cleavage within a human telomeric DNA sequence.

Main Methods:

  • A 377-base-pair DNA target containing 17 repeats of a human telomeric sequence was synthesized.
  • The DNA was fluorescently labeled, treated with bleomycin, and analyzed using an ABI 3730 automated capillary sequencer.
  • Maxam-Gilbert chemical sequencing was employed for precise mapping of bleomycin cleavage sites.

Main Results:

  • Bleomycin demonstrated significant cleavage activity within the human telomeric DNA sequence.
  • The primary cleavage site identified was 5'-GT within the telomeric repeat 5'-GGGTTA.
  • Telomeric regions accounted for 57% of the 30 most intense bleomycin damage sites analyzed.

Conclusions:

  • Human telomeric DNA sequences are a major target for bleomycin-induced DNA damage.
  • Bleomycin's sequence specificity favors telomeric regions, suggesting a potential mechanism for its anticancer activity.
  • These findings have implications for the development of targeted cancer therapies involving bleomycin.

More Related Videos

Electrochemotherapy of Tumours03:57

Electrochemotherapy of Tumours

Published on: December 15, 2008

Induction of Mouse Lung Injury by Endotracheal Injection of Bleomycin06:52

Induction of Mouse Lung Injury by Endotracheal Injection of Bleomycin

Published on: April 30, 2019

Related Concept Videos

Targeted Cancer Therapies02:57

Targeted Cancer Therapies

The targeted cancer therapies, also known as “molecular targeted therapies,” take advantage of the molecular and genetic differences between the cancer cells and the normal cells. It needs a thorough understanding of the cancer cells to develop drugs that can target specific molecular aspects that drive the growth, progression, and spread of cancer cells without affecting the growth and survival of other normal cells in the body.
There are several types of targeted therapies against specific...
Telomeres and Telomerase02:41

Telomeres and Telomerase

In eukaryotic DNA replication, a single-stranded DNA fragment remains at the end of a chromosome after the removal of the final primer. This section of DNA cannot be replicated in the same manner as the rest of the strand because there is no 3’ end to which the newly synthesized DNA can attach. This non-replicated fragment results in gradual loss of the chromosomal DNA during each cell duplication. Additionally, it can induce a DNA damage response by enzymes that recognize single-stranded DNA.
Telomeres and Telomerase02:41

Telomeres and Telomerase

In eukaryotic DNA replication, a single-stranded DNA fragment remains at the end of a chromosome after the removal of the final primer. This section of DNA cannot be replicated in the same manner as the rest of the strand because there is no 3’ end to which the newly synthesized DNA can attach. This non-replicated fragment results in gradual loss of the chromosomal DNA during each cell duplication. Additionally, it can induce a DNA damage response by enzymes that recognize single-stranded DNA.
Replicative Cell Senescence02:15

Replicative Cell Senescence

Replicative cell senescence is a property of cells that allows them to divide a finite number of times throughout the organism's lifespan while preventing excessive proliferation. Replicative senescence is associated with the gradual loss of the telomere — short, repetitive DNA sequences found at the end of the chromosomes. Telomeres are bound by a group of proteins to form a protective cap on the ends of chromosomes. Embryonic stem cells express telomerase — an enzyme that adds the telomeric...
Pharmacogenetics of Drug Targets: β₂-Adrenergic Receptors, Apo E, Thymidylate Synthase01:11

Pharmacogenetics of Drug Targets: β₂-Adrenergic Receptors, Apo E, Thymidylate Synthase

Genetic polymorphisms in drug targets have emerged as critical determinants of interindividual variability in drug response and toxicity. Pharmacogenomic investigations increasingly focus on identifying these variations to personalize and optimize therapeutic interventions. A drug target may be a receptor, enzyme, or signaling protein involved in pharmacologic responses or disease-related pathways. While early pharmacogenetic studies focused primarily on drug metabolism, current research...
Replication in Eukaryotes01:29

Replication in Eukaryotes

In eukaryotic cells, DNA replication is highly conserved and tightly regulated. Multiple linear chromosomes must be duplicated with high fidelity before cell division, so there are many proteins that fulfill specialized roles in the replication process. Replication occurs in three phases: initiation, elongation, and termination, and ends with two complete sets of chromosomes in the nucleus.
Many Proteins Orchestrate Replication at the Origin
Eukaryotic replication follows many of the same...