Platinum nanoparticles for selective treatment of liver cancer cells

Non-oxidised platinum nanoparticles have virtually no toxic effect on normal cells (bottom left). Once inside liver cancer cells (top right), the platinum is oxidised, releasing its toxic effect. Credit: ETH Zurich / Helma Wennemers

Platinum can be cytotoxic when oxidised to platinum(II) and occurs in this form in conventional platinum-based chemotherapeutics. Non-oxidised platinum(0), however, is far less toxic to cells.

Based on this knowledge, a team led by Helma Wennemers, Professor at the Laboratory of Organic Chemistry, and Michal Shoshan, a postdoc in her group, looked for a way to introduce platinum(0) into the target cells, and only then for it to be oxidised to platinum(II).

To this end, they used non-oxidised platinum nanoparticles, which first had to be stabilized with a peptide. They screened a library containing thousands of peptides to identify a peptide suitable for producing platinum nanoparticles (2.5 nanometres in diameter) that are stable for years.

Oxidised inside the cell

Tests with cancer cell cultures revealed that the platinum(0) nanoparticles penetrate into cells. Once inside the specific environment of liver cancer cells, they become oxidised, triggering the cytotoxic effect of platinum(II).

Studies with ten different types of human cells also showed that the toxicity of the peptide-coated nanoparticles was highly selective to liver cancer cells. They have the same toxic effect as Sorafenib, the most common drug used to treat primary liver tumours today.

However, the nanoparticles are more selective than Sorafenib and significantly more so than the well-known chemotherapeutic Cisplatin. It is therefore conceivable that the nanoparticles will have fewer side effects than conventional medication.

Joining forces with ETH Professor Detlef Günther and his research group, Wennemers and her team were able to determine the platinum content inside the cells and their nuclei using special mass spectrometry.

They concluded that the platinum content in the nuclei of liver cancer cells was significantly higher than, for instance, in colorectal cancer cells. The authors believe that the platinum(II) ions – produced by oxidation of the platinum nanoparticles in the liver cancer cells – enter the nucleus, and there release their toxicity.

“We are still a very long and uncertain way away from a new drug, but the research introduced a new approach to improve the selectivity of drugs for certain types of cancer – by using a selective activation process specific to a given cell type,” Wennemers says. Future research will expand the chemical properties of the nanoparticles to allow for greater control over their biological effects.

###

Reference

Shoshan MS, Vonderach T, Hattendorf B, and Wennemers H: Peptide-Coated Platinum Nanoparticles with Selective Toxicity against Liver Cancer Cells. Angewandte Chemie 2019, 58: 1, doi: 10.1002/anie.201813149 [http:dx.doi.org/10.1002/anie.201813149]

Media Contact

Helma Wennemers
helma.wennemers@org.chem.ethz.ch
41-446-333-777

 @ETH_en

http://www.ethz.ch/index_EN 

All news from this category: Life Sciences

Articles and reports from the Life Sciences area deal with applied and basic research into modern biology, chemistry and human medicine.

Valuable information can be found on a range of life sciences fields including bacteriology, biochemistry, bionics, bioinformatics, biophysics, biotechnology, genetics, geobotany, human biology, marine biology, microbiology, molecular biology, cellular biology, zoology, bioinorganic chemistry, microchemistry and environmental chemistry.

Back to the Homepage

Comments (0)

Write comment

Latest posts

Researchers confront optics and data-transfer challenges with 3D-printed lens

Researchers have developed new 3D-printed microlenses with adjustable refractive indices – a property that gives them highly specialized light-focusing abilities. This advancement is poised to improve imaging, computing and communications…

Research leads to better modeling of hypersonic flow

Hypersonic flight is conventionally referred to as the ability to fly at speeds significantly faster than the speed of sound and presents an extraordinary set of technical challenges. As an…

Researchers create ingredients to produce food by 3D printing

Food engineers in Brazil and France developed gels based on modified starch for use as “ink” to make foods and novel materials by additive manufacturing. It is already possible to…

By continuing to use the site, you agree to the use of cookies. more information

The cookie settings on this website are set to "allow cookies" to give you the best browsing experience possible. If you continue to use this website without changing your cookie settings or you click "Accept" below then you are consenting to this.

Close