Tumor-Targeted Probes Seek Out And Halt Cancers

Tumor-targeting antibodies, peptides, and nanoparticles are common techniques for delivering imaging agents or chemotherapy drugs to cancer cells. But because many cancers recur in aggressive, resistant forms, new technology is more than welcome. Scientists at the University of Wisconsin School of Medicine & Public Health and the biotechnology company Cellectar Biosciences are now reporting alkylphosphocholine analogs that can illuminate 55 different types of cancer, including lung and breast cancers (Sci. Transl. Med. 2014, DOI: 10.1126/scitranslmed.3007646). The analogs are inspired by naturally occurring phospholipid ethers, which selectively accumulate in human cancer cells instead of normal cells. The researchers, led by Jamey P. Weichert and John S. Kuo, used one alkylphosphocholine, ¹²⁴I-CLR1404, to image tumor cells in rodents with positron emission tomography. This imaging set the stage for a different analog, containing the therapeutic radioisotope ¹³¹I, to prevent tumor growth. The team also reported results from tests of the imaging analog in four human cancer patients. In one patient, the researchers found three previously unseen brain lesions. Cellectar has licensed the molecules and is testing them in multiple clinical trials.