What is the difference between stem cells and cancer cells?

Q: I want to know the difference between stem cells and cancer cells as both have the ability to proliferate and stay differentiated. Can cancer cells some day be used for clinical purposes like stem cells?

A:This is a very interesting question but no simple answer. I am giving the most simplistic answer.There are numerous differences the most important is the regulated growth and differentiation of normal stem cells where as the cancer cells have uninhibited growth and this growth is not under regulatory control. There are cancer stem cells also. Stem cell therapies are being successfully applied to cancer treatment and are fast emerging therapeutic areas.