A Case of Mistaken Identity

You couldn't make this up

"For 25 years, therefore, breast cancer research using this cell line - and
it is one of the most widely used - has been based on an incorrect model.
Melanoma-derived tumor cells are not biologically equivalent to breast
cancer cells; they have different molecular and genetic characteristics. "


NEWSBRIEF: STARTLING REVELATION ABOUT BREAST CANCER RESEARCH


This week, the online life sciences magazine The Scientist published an
article whose implications for breast cancer research are profound.

Tumor cell lines - living cells taken from tumors and cultured in the
laboratory - are the mainstay of cancer research at the most fundamental
level, and are used as the model for studying tumor behavior and response to
treatment. For the past 25 years, most of the laboratory research into
metastatic breast cancer has been based on a single breast tumor cell line
known as MDA-MB-435. At least 650 papers have been published on studies
involving this cell line. Yet it has been revealed that this supposed breast
cancer cell line may in fact not be composed of breast cancer cells at all.
Instead, it appears that the cells are derived from melanoma. For 25 years,
therefore, breast cancer research using this cell line - and it is one of
the most widely used - has been based on an incorrect model.
Melanoma-derived tumor cells are not biologically equivalent to breast
cancer cells; they have different molecular and genetic characteristics.

Cell lines - even when correctly sourced and identified - are an
intrinsically flawed model, and in the past I have often cautioned against
the tendency to read too much into the results of cancer research done on
tumor cell lines. The inferential leap from Petri dish to living human
cancer patient is simply too large: an enormous number of drugs and
experimental techniques show significant activity in cultured cancer cell
lines, only to exhibit no benefit whatever when given to human subjects in a
clinical setting. Furthermore, cell lines can degenerate over time, becoming
genetically unstable. But these are relatively small concerns compared to
the discovery that MDA-MB-435, the cornerstone of breast cancer research, is
not breast cancer at all.

We are constantly being reminded that this is the era of evidence-based
medicine. But if the very cell lines which have provided the foundation for
breast cancer research for the past quarter century have now been
conclusively shown to be melanoma cells, not breast cancer, how solid or
trustworthy is the evidence on which current breast cancer treatment is
based? Evidence built on such flawed foundations more closely resembles
hearsay than science.

A Case of Mistaken Identity by Megan Scudellari. The Scientist, September
16th 2008
http://www.the-scientist.com/news/display/55013/ (registration required)