If cancer occurs only in dividing cells, how can the brain develop cancer even though all brain cells are differentiated and don't divide?

Explanation:

Cancer occurs in dividing cells only because genetic materials divide into two equal portions during division. This process may be interrupted by carcinogenes or mutagenes to make mutate cells and then render them as cancer cells. In the brain, the cells are differentiated and there is no chance to start division, then how can cancer be found in the brain.

c.) polymerase chain reaction

- "unlike the original dna fingerprinting method, dna profiling does not use restriction enzymes to cut the dna. instead it uses the polymerase chain reaction (pcr)? to produce many copies of specific str sequences. pcr is an automated procedure that generates lots of copies of a specific sequence of dna."