PO information need to deleted from live cache

How can we delete the PO quantity, item number and ordered quantity from live cache for a partnumber since we do not want the above PO information to be displayed in planning book.

Reason : The part number is no longer going to be supplied by the vendor therefore would want to delete the entire PO information from Live cache so that it is not diplayed in the planning book.

Please suggest for the same.

Thanking you all for your support,

Regards,

Gayatri.