High levels of the CPE-delta N protein in tumor cells indicate an increased likelihood that the cancer will metastasize and spread to other parts of the body. Testing cancer tumors for amounts of this protein could help more accurately estimate the risk of cancer spreading when used along with other diagnostic methods. The researchers measured levels of an RNA molecule that assists in producing the CPE-delta N protein to indirectly assess amounts of the protein. Understanding the molecular structure and role of proteins like CPE-delta N is important for developing targeted cancer treatments and preventing the disease.