some.php

function change_post_menu_label() {
  global $menu;
	global $submenu;
	$menu[5][0] = 'News';
	$submenu['edit.php'][5][0] = 'News';
	$submenu['edit.php'][10][0] = 'Add News';
	$submenu['edit.php'][16][0] = 'News Tags';
	echo '';
}
function change_post_object_label() {
	global $wp_post_types;
	$rewrite = &$wp_post_types['post']->rewrite;
	$rewrite->slug = 'some-slug';
	$rewrite->with_front = false;
#	$labels->add_new = 'Add News';
#	$labels->add_new_item = 'Add News';
#	$labels->edit_item = 'Edit News';
#	$labels->new_item = 'News';
#	$labels->view_item = 'View News';
#	$labels->search_items = 'Search News';
#	$labels->not_found = 'No News found';
#	$labels->not_found_in_trash = 'No News found in Trash';
}
add_action( 'init', 'change_post_object_label' );
add_action( 'admin_menu', 'change_post_menu_label' );