CNIO researchers discover new strategies for the treatment of psoriasis

Almost ten years ago, the group led by Erwin Wagner, currently at the Spanish National Cancer Research Centre (CNIO), developed genetically modified mice showing symptoms very reminiscent to psoriasis. After publishing this discovery in Nature, the researchers decided to use this mouse model to study the underlying molecular pathways involved in disease development, and to look for innovative and efficient therapies. Now the group has discovered two possible novel treatments, based on existing pharmacological compounds, which are likely to cause fewer side effects.

Psoriasis affects up to 3% of the world's population and can seriously affect the quality of life of these patients. The primary causes are largely unknown and the disease is not curable. The latest generation of drugs developed to combat it - so-called biological therapies - are thought to be a big step forward, but can only be applied for limited periods of time due to serious side effects, which can generate other forms of psoriasis, or even cause tuberculosis or leukaemia. Due to this it is important for psoriatic patients to develop efficient non-toxic treatments.

The two new strategies now published by CNIO researchers are the result of in-depth studies of the disease biology that have revealed some of the underlying molecular causes.

In the first study published in the December issue of the high impact journal Immunity, it is shown how the symptoms of psoriasis disappear by deleting a protein called S100A9. In the second article, which is published in Science Translational Medicine, the researchers show that inhibiting a non-coding micro RNA, named miR-21, ameliorates the disease symptoms.

As Helia Schönthaler, the first author, and collegues write in Immunity: "over the past decade, biological therapies have been shown to be effective against inflammatory diseases. These treatments, however, are a cause of worry due to their side effects, which might cause a possible increase in the risk of infection or cancer. The development of efficient, locally applicable drugs without these side effects, therefore would be beneficial for patients with psoriasis". Specifically, S100A9 inhibiting strategies "have the potential to become effective new treatments against psoriasis", the authors state.

What is Psoriasis? Psoriasis is a relatively common skin condition affecting 1% to 2% of the population. The main feature of psoriasis is a red, scaly area or patch. The patches appear particularly on the knees, elbows and scalp and sometimes on other parts of the trunk, and legs. Psoriasis affects both sexes and all races. It can occur at any stage of life, although it starts most frequently in young adults.

Itching is usually only mild. Psoriasis only rarely affects general health apart from arthritis. A flare in a person’s psoriasis can, however, have a profound impact on an individual’s feelings of wellbeing and have a major impact on their way of life and daily activities. Once a person develops psoriasis it usually continues, although it may get better or worse over time and even seem to disappear for prolonged periods.