Triple positive cancer stem cells (CSCs) subtset of CTCs implicated in Metastasis

Key findings:

• A subset of CTCs occurring at low frequency are responsible for metastasis
• the frequency of occurrence in the reported study was 0 .6 to 33% of CTCs
• This subset is positive for CD44, CD47, MET 
• experimental method involved isolating CTCs from 350 breast cancer patients using cell surface markers and transplating them in mice with defective immune system
• As the disease advances, the number of triple-positive cells increases, but the total number of CTCs does not. 
• Patients with very high numbers of triple-positive cells had particularly high numbers of metastases and a much poorer prognosis than women in whom only few of these metastasis-inducing cells were detected

Conclusion: "On the whole, triple-positive cells seem to have a substantially higher biological relevance for disease progression than previously studied CTCs"

Metastasis stem cells in the blood of breast cancer patients discovered

direct link to the nature biotechnology paper
http://www.nature.com/nbt/journal/vaop/ncurrent/full/nbt.2576.html

Lessons from On-Q-ity's failure: Reflections of a VC who invested in the company

On-Q-ity, a Cancer Diagnostic Company: R.I.P. | LifeSciVC

On-Q-ity recently announced closure of its operations. Bruce Booth, a VC who invested in On-Q-ity reflects on the lessons learnt from this unsuccessful venture.

Booth covers several key learnings, including the significance of team, product focus, getting the market timing right.

Many of these are routinely covered in venture advice articles. Its still worth reading from the point of view of someone who went through the drill. 

I highly recommend giving it a read as its relevant to any CTC company and there are many startup companies trying to commercialize CTC technologies. You can find the updated list of CTC companies in this post.
http://circulating-tumor-cells.blogspot.sg/2010/12/commercial-circulating-tumor-cell-ctc.html

CTC-iChip from MGH: Third-generation device significantly improves capture of circulating tumor cells - Massachusetts General Hospital, Boston, MA

Third-generation device significantly improves capture of circulating tumor cells - Massachusetts General Hospital, Boston, MA

A video of this work can be found here
http://www.eurekalert.org/multimedia/pub/55044.php