Gold Nanoparticles Tagged With Radioactive Substance in the Treatment of Cancer

Highlights:

• Gold nanoparticles are used to direct anti-cancer medications into cancer cells
• Researchers tagged gold nanoparticles with radioactive substance and proved their site of action on the enzyme telomerase
• Further research in this field could mean that similar treatment could be used in patients with telomerase-positive cancers

Researchers from the CRUK/MRC Oxford Institute for Radiation Oncology have tagged gold nanoparticles with a small dose of radiation and studied their movement and effect in telomerase-positive cancer cells in the laboratory. Their study was presented as a poster at the 2016 National Cancer Research Institute (NCRI) Cancer Conference.

Treatment of cancer has progressed over the years. From being an incurable condition, today several cancers can be cured especially in the early stages. However, side effects from chemotherapy and radiotherapy continue to be a challenge. Targeted treatments with medications that more specifically attack cancer cells without damaging normal cells have reduced the adverse effects of the treatment.

Gold is no longer a metal that is useful only as jewelry. It is now used in several other spheres of life including medicine.

Gold nanoparticles have found their use in various diagnostic procedures like immunochromatography and dot immunoassay. In addition, anticancer medications can be packed into the nanoparticles which carry the drug to the cancerous target, thereby reducing side effects to normal body tissues.

The researchers conducted their studies using a drug that targets the enzyme telomerase in the cancer cells. Every chromosome has caps at its ends called telomeres.The telomeres protect the chromosome, so that the cell can divide correctly.

As the cell divides repeatedly, the size of the telomeres decreases and it finally becomes so short that the cell cannot divide any further. This reduces the regenerative capacity of tissues with age. The length of the telomeres is maintained by the enzyme telomerase. Cancer cells have increased telomerase activity, due to which the cells continue to multiply and result in a cancerous growth.

The researchers tagged the gold particles with a small dose of radiation. Due to the radiation, it was possible for the researchers to study the movement of the gold particles into the cancerous cells. The experiment was conducted on cells obtained from a skin cancer called melanoma which were telomerase positive and grown in the laboratory.

The researchers were able to demonstrate that the gold particles reached the desired site in the cancer cells and shut telomerase down, thereby stopping the growth of the cancer calls.

Adding radiation to the gold particles not only helps to study the passage of the gold particles into cancer cells, but the radiation also causes some damage to the cancer cells and therefore could provide additional benefit. The cells which are already damaged by the drug in the gold nanoparticles become more sensitive to radiation, and therefore can be killed more easily.

Further advancements in this field including clinical trials could make using the treatment in humans a reality.

References

1. Bas Bavelaar, Lei Song, Mark Jackson, Philip Waghorn, Katherine Vallis. Gold nanoparticle radiopharmaceuticals for the selective treatment of telomerase-positive tumours. Poster presentation. 2016 National Cancer Research Institute (NCRI) Cancer conference.
2. Gold nanoparticle radiopharmaceuticals for the selective treatment of telomerase-positive tumours - (http://abstracts.ncri.org.uk/abstract/gold-nanoparticle-radiopharmaceuticals-for-the-selective-treatment-of-telomerase-positive-tumours/)
3. Dykman LA, Khlebtsov NG. Gold Nanoparticles in Biology and Medicine: Recent Advances and Prospects. Acta Naturae. 2011 Apr-Jun; 3(2): 34-55.

Source: Medindia