There’s a lot of research these days aimed at identifying
characteristics of cancer cells that make them susceptible to particular
treatments, as breast-cancer cells with extra expression of the her2
protein are treatable with Herceptin.
Equally important, it seems to me, is identifying cancers that will not
respond to standard chemo, which can be hugely debilitating. It would
be a great help to patients if doctors could tell before administering a
single dose whether the chemo will help. Now scientists at MIT have shown, in a paper in the online edition of the journal Genes and Development, that 48 specific genes explain a good deal of the variation in whether malignant cells will be killed by chemo. The old-line chemo drugs, such as those based on platinum compounds such as oxaliplatin,
work by damaging DNA. That prevents malignant cells from multiplying.
But the MIT scientists find that a group of 48 genes can predict how
susceptible a patient is to a toxic compound called MNNG that, like
common chemo agents, kills cells by inducing irreparable DNA damage.
Which of the 48 genes someone has produces huge variability in response
to DNA-damaging compounds. “A cell line from one person would be killed
dramatically, while that from another person was resistant to exposure,”
said Rebecca Fry, former MIT research scientist and lead author of the
paper who is now at the University of North Carolina School of Public
Health. “It wasn’t known that cell lines from different people could
have such dramatic differences in responses.” |