Precision highlights role of ChemoFx test, multi-gene predictors for breast cancer

[gdpawel]

It's interesting that you brought up about the legendary leaders in China testing the effectiveness of herbs.

Ralph W. Moss' new book, "Customized Cancer Treatment" talks functional profile. He makes a very good case for drug sensitivity tests to see which drugs will work best. He does a tremendous job turning over every single stone why The Test (as he calls it in the book) has struggled to gain acceptance in the billion dollar cancer medicine industry, and putting together in one book all of the research I've ever read over the last decade about cell culture assays.

I was intrigued by Moss' association of cell culture assays and CAM in the final conclusions of the book. He feels that there are many treatments of natural origin that have been proposed as candidates for cancer therapy. Some of these may have great value. He reminds us that about one-quarter of all chemotherapeutic agents had a natural origin.

Moss feels that cell culture assays, when applied to CAM, would provide a similar service as it does to chemotherapy and could become the ultimate guide to choosing treatments that are likely to work and avoiding those that do not, at least in terms of causing programmed cell death (apoptosis).

He points out that at the present time, none of the American chemosensitivity laboratories "routinely" screens natural agents, although one of them has communicated to me that on occasion, they have screened such agents if the patient and physician explicitly requests it and provides a sample.

Moss feels that there is no reason that other labs could not and would not do this sort of CAM testing if the cell culture assays were made routine. Not all CAM treatments work by means of stimulating programmed cell death, but those that do could be discovered via the assay.

http://www.amazon.com/Customized-Can.../dp/1881025012

[gdpawel]

As Dr. Robert Nagourney, medical and laboratory director at Rational Therapeutics, and instructor of Pharmacology at the University of California, Irvine School of Medicine describes it, recent press coverage from the San Antonio Breast Cancer Symposium (SABCS) touched upon the development of multi-gene predictors for clinical response in breast cancer.

One report from that meeting described correlations between a laboratory assay model in use at the University of Pittsburgh and microarray analyses. However, the suggestion that this laboratory technique - described by its proponents as a chemosensitivity assay - could accurately identify gene profiles that would predict response seems at odds with the current literature.

Although the press coverage concluded that this technique showed “promising performance” it was largely exploratory and defined by the authors as a “validation study.”

What is interesting is that a team of highly reputable investigators from M.D. Anderson recently reported a very negative study using a similar approach of identifying target genes in cell lines and then correlating them with patient outcomes.

In the paper, published in the June 2010 issue of Breast Cancer Research and Treatment (Liedtke, C. et al. Breast Cancer Res Treat. 2010 Jun; 121(2):301-9) the authors reported “cell line derived predictors of response to four commonly used chemotherapy drugs did not predict response accurately in patients.”

Indeed, differential gene expression seemed only to correlate with paclitaxel. The authors found that false discovery rates were high for all other drugs tested. Thus, the report from the SABCS will need to be carefully examined to determine whether truly relevant clinically predictive information can be provided by this particular laboratory platform.