Mitosis is a type of cell division which produces two identical diploid daughter cells. Cancerous tumours are either malignant or benign. Specialised cells are formed when stem cells differentiate.
It is important to obtain a balanced view. Sometimes, there are no right or wrong answers. Other times there are no answers at all. Some variables which would be considered when discussing stem cells include:
Clinical issues
There is no guarantee of how successful these therapies will be, for example in the use of stem cells in healing damage caused by Parkinson's disease.
The difficulty in finding suitable stem cell donors.
The difficulty in obtaining and storing a patient's embryonic stem cells.
Mutations have been observed in stem cells cultured for a number of generations, and some mutated stem cells have been observed to behave like cancer cells.
Cultured stem cells could be contaminated with viruses which would be transferred to a patient.
Ethical issues
A source of embryonic stem cell is unused embryos produced by in vitro fertilisation.
For therapeutic cloning, is it right to create embryos for therapy, and destroy them in the process?
Embryos could come to be viewed as a commodity, and not as an embryo that could develop into a person.
At what stage of its development should an embryo be regarded as, and treated as, a person?
Social issues
Educating the public about what stem cells can, and can't do, is important.
Whether the benefits of stem cell research use outweigh the objections.
Much of the research is being carried out by commercial clinics, so reported successes are not subject to peer review.
Patients could be exploited by paying for expensive treatments and being given false hope of a cure as stem cell therapies are only in their developmental stages.