WordPress: Create custom permalink based on custom field or other value.

functions.php

<?php
add_filter( 'wp_insert_post_data', 'cg_custom_insert_post_data' );
function cg_custom_insert_post_data( $data ) {
    //You can make some checks here before modify the post data.
    //For example, limit the changes to revista post type
    if( 'revista' == $data['post_type'] ) {
    	$edicao_num = 'Edição: '.$_POST['_edicao_num'];
        $data['post_name'] = sanitize_title( $edicao_num );
    }
    return $data;
}