Using the same tests used to judge new chemotherapies, the SETH team discovered that this herbal compound kills human brain tumor cells at a concentration that is nontoxic to normal brain cells. A computerized microscope captured images of the cells every 5 minutes to compile the time-lapse videos. After 20 hours of treatment, Δ9-THC kills all cancer cells but leaves normal brain cells alive. Cell death is evidenced by cells shrinking to inanimate white spheres. LEARN MORE