Try the following function, which is the one i use:
xprofile_get_field_data('Profile',$u_id);
$u_id is the user ID in case you are not in a members loop.
So in your case should be:
<?php if ( xprofile_get_field_data( 'Profile', $user_ID ) ) : ?>
<?php echo '<BR><span class=memberslabel>Profile:</span> '; ?>
<?php echo xprofile_get_field_data( 'Profile', $user_ID ); ?>
<?php endif; ?>
UPDATE : You will need to paste your whole code to be sure you are using this on the right place. But you could try something like:
<?php while ( bp_group_members() ) : bp_group_the_member(); ?>
<li>
<a href="https://wordpress.stackexchange.com/questions/106040/<?php bp_group_member_domain(); ?>">
<?php bp_group_member_avatar_thumb(); ?>
</a>
<h5><?php bp_group_member_link(); ?></h5>
<span class="activity"><?php bp_group_member_joined_since(); ?></span>
<?php do_action( 'bp_group_members_list_item' ); ?>
<?php if ( bp_is_active( 'friends' ) ) : ?>
<div class="action">
<?php bp_add_friend_button( bp_get_group_member_id(), bp_get_group_member_is_friend() ); ?>
<?php do_action( 'bp_group_members_list_item_action' ); ?>
</div>
<?php endif; ?>
<?php
$user_ID = bp_get_group_member_id();
if ( xprofile_get_field_data( 'Profile', $user_ID ) ) : ?>
<?php echo '<BR><span class=memberslabel>Profile:</span> '; ?>
<?php echo xprofile_get_field_data( 'Profile', $user_ID ); ?>
<?php endif; ?>
</li>
<?php endwhile; ?>