Developmental biology, regenerative medicine and cancer biology are increasingly occupied with the molecular characterization of stem cells. Yet recent work adds to a growing body of literature suggesting that 'stemness' cannot be reduced to the molecular features of cell types, and is instead an emergent property of cell lineages under feedback control.Brief excerpt from the full text: "Like gene or phlogiston, the term 'stem cell' is a scientific concept. Stem cells are very much in the news, thanks to a dramatic upsurge in interest in their therapeutic potential".
Another excerpt from the full text:
For example, in the case of cancers that are stem cell driven, it is not clear that we actually have grounds to assume that the specific chemotherapeutic targeting of cancer stem cells will necessarily stop tumors in their tracks. Indeed, if feedback and lineage progression continue to take place in cancerous tissues, we might observe that, under different conditions - different stages of tumorigensis, different parts of a tumor, different amounts of tumor cells - that different cell types will assume the role of 'cancer stem cell'. The therapeutic implications of this possibility are clearly substantial.An interview with Arthur Lander is at: Q&A: Is stem cell research misguided? by Bob Grant,TheScientist.com, September 29, 2009 [FriendFeed entry].
Comment: The major contrarian perspective in this opinion piece is the comparison of the stem cell concept with the phlogiston concept. This comparison is discussed further in the Q & A interview. The Comments section of Dr. Lander's article includes an answer to a question that I asked: What about purified stem cells? As part of a discussion on FriendFeed, I also asked: Is the debate about 'stemness' becoming another version of the nature-nurture debate? So far, no response to this question.