This will setup your system with the latest Filezilla version and will allow you to keep it up to date with regular system updates.
sudo sh -c 'echo "deb http://archive.getdeb.net/ubuntu xenial-getdeb apps" >> /etc/apt/sources.list.d/getdeb.list'
wget -q -O - http://archive.getdeb.net/getdeb-archive.key | sudo apt-key add -
sudo apt update
sudo apt install filezilla
References:
http://ubuntuhandbook.org/index.php/2016/06/install-latest-filezilla-ubuntu-16-04/