It's about reactions to a freely-accessible article entitled: "CD133 expression is not restricted to stem cells, and both CD133+ and CD133- metastatic colon cancer cells initiate tumors", by Sergey V Shmelkov and 19 co-authors, in J Clin Invest. 2008(Jun); 118(6): 2111-20. The final sentence of the abstract of this article:
Collectively, our data suggest that CD133 expression is not restricted to intestinal stem or cancer-initiating cells, and during the metastatic transition, CD133+ tumor cells might give rise to the more aggressive CD133– subset, which is also capable of tumor initiation in NOD/SCID mice.The commentary in Nature Medicine isn't freely accessible, and has no abstract. It consists mainly of answers to the question: "What do the findings mean for the quest to find and target cancer stem cells?". Answers are provided by Zena Werb, Jeremy Rich and Jeffrey Rosen. Excerpts:
For understanding tumorigenesis and creating therapies, a spectrum of markers may be the answer. [Zena Werb]
No single marker is likely to be absolutely informative, but CD133 has proven repeatedly useful in brain tumor stem cell studies for many research groups. [Jeremy Rich]
[T]he findings do not invalidate previous stem cell work using CD133 antibodies, which recognize a specific epitope that may not be conserved between mice and people. [Jeffrey Rosen]Other comments about the article by Shmelkov and co-authors, or about the commentary in Nature Medicine, would be welcomed.