Brain cancer cell. Coloured scanning electron micrograph (SEM) of a cancerous cell from a glioblastoma. Glioblastoma is an aggressive type of cancer that can occur in the brain or spinal cord. Glioblastoma forms from cells called astrocytes that support nerve cells. Glioblastoma can occur at any age, but tends to occur more often in older adults. It can cause worsening headaches, nausea, vomiting and seizures. Glioblastoma, also known as glioblastoma multiforme, can be very difficult to treat and a cure is often not possible. Treatments may slow progression of the cancer and reduce signs and symptoms. Magnification: x5000 when printed at 10 centimetres wide. Specimen courtesy of Professor Greg Towers and Hashim Ali, University College London, UK.