Molecular-Genetic Imaging Shows Individual Prostate Cancer Cells
Knowing cancer is out there, but not knowing where, has long frustrated doctors and men who have cancer that has spread beyond the prostate. Now Hopkins scientists have developed a new imaging method that specifically targets cancer cells. The method involves injecting a nanoparticle sensor that "only becomes activated when it encounters malignant cells, explains radiologist Martin Pomper, M.D., Ph.D., "but not normal tissue, so that cancer and its metastases can be detected anywhere in the body." The method has performed well in imaging studies of mice with metastases, including those due to prostate cancer.
This work, which has been published in Nature Medicine and Cancer Research, is based on years of research into the genes and transcription factors that make malignant cells different from normal cells. "To image the cancer, after injecting the nanoparticle sensor, we also inject an imaging agent to detect the genes turned on by the cancer."
Pomper and colleagues have also designed imaging agents that bind to prostate-specific membrane antigen (PMSA), a marker for prostate cancer. A clinical trial with the firs t-generation nanoparticle-sensor is in the planning stages, while the first- and secondgeneration PSMA-targeted imaging agents recently have completed first-in-human studies.