Question - can you keep a cancer cell alive in a petri dish and also can you keep skin cells alive in the same fashion. Most human cells are hard to keep alive for long in culture. They divide a few times and then die. The older the person was from whom the cells were taken, the fewer divisions before the line dies out.
Cancer cells are easy to grow in culture.
So the answer to your question is that cancer cells are easy to grow in culture, but healthy cells are more of a challenge. Argonne National Laboratory, Division of Educational Programs, Harold Myron, Ph.D., Division Director.