WHAT CAUSES EHE?

This is an important question since the first step to treating a disease is knowing its cause.

 

Many things have been speculated as potential causes of EHE, including:

  • Hormonal effects,

  • Birth control pills,

  • Industrial exposures (vinyl chloride),

  • And trauma

Fortunately

Significant progress has been made very recently in our understanding of EHE.

 

Two separate research groups

published findings in late 2011 indicating a specific chromosomal translocation that is virtually diagnostic for EHE.

 

This swapping of genetic material

between chromosomes 1 and 3 is seen in almost all EHE tumor cells and can be considered ‘disease defining’.

 

This genetic alteration

results in the production of a fusion gene and a resulting fusion protein: it has part of a protein that is normally seen only in endothelial cells and a part that is normally found only in the brain.

 

This abnormal fusion protein

presumably causes the cells to grow without normal regulation. It is this abnormal system that could theoretically be targeted for therapy.

 

However

to begin testing possible treatments we need to develop laboratory models of EHE: that is, cells or animals that contain the translocation and resulting fusion protein. CRAVAT Foundation has already funded important research in this area.

But wait, there is more!

A different, less mainstream line of investigation

has recently implicated a possible association between EHE and infection by Bartonella bacteria.

 

This bacterium

is unique in that it has the ability to cause endothelial cells to proliferate – the underlying biological problem in EHE.

 

Many cancers

are thought to result from “two hits” and it is possible that Bartonella infection comprises the other ‘hit’ after the disease defining translocation, possibly by stimulating synthesis of the fusion protein.

 

This is entirely speculative;

it is good to know there are several possible lines of investigation that could lead to progress in a better understanding of EHE and, possibly a treatment.