Welcome to the Nanomedicine homepage, which features news and information about the different projects in the research group led by Lars Herfindal.

Can zebrafish larvae get human leukaemia?

We have been working with zebrafish larvae as a model system for human diseases for a while, and have recently showed that they are excellent systems to study development of leukaemia. Fluorescently labelled leukaemia cells can be transplanted into the larvae by intravenous injection. In a recently published paper, we have written a software plug-in which automatically counts the number of individual leukaemia cells based on confocal microscopy images. In this way, we can follow how the leukaemia develops, both over time, and how they distribute in the larvae. Although tailor-made for larvae transplanted with leukaemia cells, the software can be used to analyze any fluorescent particle. This work was recently published in Biology open.

Liposomes designed to protect the heart during cancer therapy

One of the main advantages of using liposomes to encapsulate anti-cancer drugs is that normal tissues like the heart is protected from harmful effects. Still, liposomal drugs are not the first choice partly because they are not more effective in killing cancer cells. We wanted to add further protection of the heart by adding statins in the liposomes along with the anti-cancer drug doxorubicin. Statin protects the hearts from being damaged by doxorubicin, and to our pleasant surprise, also potentiated the anti-cancer effects. We managed to develop a liposome carrying both statins and doxorubicin, and our liposomes had the same protecting effect on the heart, while retaining the increased ability to kill cancer cells. Although both these drugs can be administered in their free form, liposomal encapsulation is a huge advantage, since both drugs will be equally distributed in the body. Then the heart will be protected, and the cancer cells efficiently killed by the presence of both drugs at the same time.
The results was recently published in International Journal of Pharmaceutics.

New formulation for repurposing of drugs

Repurposing, or redefinition of drugs from one disease to another, is a way to improve treatment of diseases with few therapy options. For acute myeloid leukaemia, the anti-psychotic drug chlorpromazine has showed good effect in cell cultures in vitro. However, it has quite dramatic effects on the central nervous system in non-psychotic individuals. PhD student Edvin Tang Gundersen has developed a nanoparticle which encapsulates chlorpromazine, and prevents it from entering the central nervous system. The formulation is efficient towards AML cells and the nanoparticles prevent the encapsulated molecules crossing from the blood into the central nervous system in zebrafish larvae. The work was recently published in International Journal of Pharmaceutics.

New and promising nanocarriers in cancer therapy

Together with Hanne R Hagland and Abdelnour Alhourani at the University of Stavanger, we have investigated if graphene nanosheets can be used to transport small anti-cancer drugs in the blood. Graphene nanosheets have unique properties that are not found in other nanomaterials, such as a very high surface area for absorption of drugs. We found that graphene released the drugs at low pH, which are perfect for cancer drugs, since most tumours have lower pH than the rest of the body. We also demonstrated that pristine graphene is superor to graphene oxide, but that PEGylation is needed to ensure that the nanosheets disperse nicely in aqueous media. The work was just accepted for publication in ACS Omega.

New drugs inspired from the nature

Many years ago, we came across an interesting compound, iodinin, from marine benthic bacteria, which selectively induced apoptosis in leukaemia cells. In fact, the compound was first described more than 70 years ago, but has not been left much attention. We also almost put it aside, until our good collaborators Pål Rongved and Elvar Örn Viktorsson managed to develop a method to synthesise iodinin in the lab, and even better, produce variants which could be even better as drugs. We recently got our work accepted for publication in RCS medicinal chemistry. Here, Pål and Elvar has produced more than 60 analogues of iodinin, which we tested for ability to kill leukaemia cells. The results can tell us something about which parts of the molecules are crucial for the activity, and which part can be improved so we get even better activity, and milder side-effects.

Our own nanocarriers can also transport drugs

Inside our blood, there are several natural nanocarriers. Lipoproteins are small packages of lipids, stabilised by proteins. These transport lipids and some lipid-soluble vitamins in the blood, and deliver them at the target sites. We have found that some lipid-soluble drugs also  associate with lipoproteins, and a large fraction of these are transported by lipoproteins rather than serum proteins. This new concept of drug transport in the blood means that we have to think differently when estimating pharmacokinetic properties of some drugs. The paper was published in the journal Therapeutic Drug Monitoring.

New molecules to treat leukemia?

Although immune-based therapies emerge as promising to fight cancers, we will still rely on small molecules for most of the patients. Together with researchers at Clermont-Ferrand, we have investigated inhibitors of Pim-kinases to kill acute myeloid leukaemia cells. Of the molecules we tested, one was particularly promising, and proved efficient also towards leukaemia cells isolated from patients that had developed chemotherapy resistance. Why was our molecule so efficient? Probably because in addition to blocking Pim-kinase activity, it also inhibited other key signalling factors in the leukaemia cells. The work was recently published in Molecular Cancer Therapies.

The figure shows the different molecules tested, and VS-II-173 stands out being very efficient towards acute myeloid leukaemia (AML) cells, and not towards non-malignant cells. Green indicates low toxicity, red indicates high toxicity.

Nanomedicine in cancer treatment in children

Can nanocarriers improve therapy for children with cancer? This is something we want to find out, and we recently received a grant from the Norwegian Children’s Cancer Society to investigate this. This is part of a large project, led by specialist in pediatric cancer Maria Winther Gunnes, and with Camilla Tøndel, Randi Hovland, and Emmet McCormack as project participants. Together, we hope to improved the treatment of cancer in children.

Article with Maite and Aurora on enzyme-loaded nanoparticles

Just after Christmas, we got the nice news that our manuscript on tyrosine hydroxylase (TH) in nanoparticles was accepted for publication in Bioconjugate Chemistry. This work describes an amitious, but very elegant principle for treatment of neurodegenerative diseases like Parkinson’s disease. In this disease, the patients suffer from loss of enzyme activity. We showed that it was possible to load functional enzymes into nanoparticles. The nanoparticles internalize the functional enzymes both in cells in culture, and in animals. The work was mainly done by Maite and Fredrik in Aurora Martinez’ group, but also with contributions from Edvin and myself.

Sarah and Ronja present poster at the CCBIO annual symposium

This year, we decided to join most other cancer researchers in Bergen to the CCBIO annual symposium at Solstrand hotel. Sarah and Ronja presented a poster on their findings on how the cAMP receptors Epac1 and PKA influences the pressure inside tumours, and subsequently nanoparticle accumulation. This was part of Sarah’s master thesis, and Ronja has supplied excellent data on tumour pressure measurement. A poster is the first presentation of data, and has given us an idea of how the final article will be. We will now start to gather together a manuscript.
imag0184Here are the two happy scientists in front of the poster presenting their research.