Write data in XML file

Hi all

I have XML as shown below

<?xml version="1.0" encoding="utf-8"?>
<Configuration>
<APIkey>ab15c4d132d2argrjfvvb952ca886a92e5a-us14</APIkey>
</Configuration>

I want to change this APIkey when I have a new APIkey. How can I change it by using Javascript.?

Thank You