Cancer stem cells – because sex sells (and specificity doesn’t)

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We know that success in research is dependent on public interest and funding, among a great many other things. Public interest helps drive long-term support, but to get that interest you need to generate excitement. So how do you excite people – many of whom are non-scientists – about scientific research? How about sex appeal? I don’t mean in the sense of Marilyn Monroe (at least, I’ve never seen it done that way), but by using words that invoke certain emotions, making the research ‘sexy’ and appealing to researchers and non-researchers alike. While this approach works, it has a downside: loss of scientific specificity.

An example of this can be found in the field of cancer stem cell biology. The foundation of this field is “cancer stem cells”, a term that suggests we are talking about normal stem cells that have become cancerous. While this is not true, it isn’t entirely inaccurate either.

The term “cancer stem cell” or “CSC” developed as a result of one of the new models for cancer development. In this model, researchers hypothesized that a subgroup of cancer cells was responsible for producing all cell types found within the tumour. These cells differ from the majority of tumour cells, which are not capable of forming a “new” tumour (see image below; or view a simple animation here). This model was, and remains, particularly attractive as these cells were also hypothesized to have characteristics that allow them to evade chemotherapy and radiation; and thus, were considered to be the cells responsible for relapse and/or spread of disease. The popularity of the CSC model has continued to grow alongside a substantial body of scientific evidence supporting it in many cancer types.

The cancer stem cell model of tumour development

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The key thing to remember when learning about CSC biology, is the functionality of these cells, as outlined by a workshop in 2006, hosted by the American Association for Cancer Research (go here for the proceedings). These cells are stem cell-like in that they possess functional stem cell properties. These properties include self-renewal and hierarchical differentiation, which together enable a cell to undergo cell divisions that produce an identical copy of itself, maintaining the stem cell pool (self-renewal); while simultaneously producing a more mature and ‘committed’ cell, within the cellular hierarchy, that has lost the ability to self-renew (differentiation). What is NOT being suggested is that these cells were once normal, healthy stem cells that became cancerous (while possible, the origin of CSCs is another story). We are not targeting cells that look a particular way (also an intriguing line of study, but once again, another story), but rather, a group of cells that behave a certain way. Herein lies the power of the CSC model – it encourages us to focus on the functional importance of these cells, allowing us to determine possible ways by which we can eradicate this treatment-resistant population.

While “cancer stem cells” as a group of cells with functionally distinguishable characteristics is well understood within the CSC research community, it’s pretty clear that this true meaning is often lost when used with a broader audience. The problem isn’t necessarily “cancer,” which is easy enough to wrap our heads around, but in “stem cells” and the assumptions one makes when the two terms come together. “Stem cells” in any context can be a tad misleading, particularly if they are only understood with relation to embryonic stem cells. And I’ve already mentioned what is assumed about “cancer stem cells” in the absence of an accurate definition. I’m sure a more accurate term like “tumour-initiating cells” (favoured by researchers, as it implies tumour-formation capacity) would be understood by everyone.

So why not use those more scientifically specific terms? It comes back to needing to grab attention. “Tumour-initiating cells” has less ‘sex appeal’ than “cancer stem cells.” While far from actually being sexy, the term “cancer stem cells” piques our interest. There is an aura of mystique, and something akin to desire – a desire to know more – stirs within. At the end of the day, is it the desire of the masses to conquer cancer that leads to support, progress, and, finally, attainment of this desire.

Research cited:

Clarke M.F., Dick J.E., Dirks P.B., Eaves C.J., Jamieson C.H.M., Jones D.L., Visvader J., Weissman I.L. & Wahl G.M. (2006). Cancer Stem Cells–Perspectives on Current Status and Future Directions: AACR Workshop on Cancer Stem Cells, Cancer Research, 66 (19) 9339-9344. DOI: 10.1158/0008-5472.CAN-06-3126