It turns out some cancers can't stand the heat. Although studies
have shown that heating tumours facilitates chemotherapy and
radiation therapy, no one was sure why. Now, it appears that
high temperatures dismantle enzymes that work against cancer
drugs. The discovery suggests that the right combination of
drugs and heat will improve the effectiveness of chemotherapy.
Przemek Krawczyk at the University of Amsterdam, the
Netherlands, and colleagues heated up tumour cells in Petri
dishes. They also injected tumours into rats, and then heated
the tumour-bearing hind limbs in a water bath set at 42 °C for
90 minutes. The team discovered that high temperatures denature
the BRCA2 protein, a DNA-repair enzyme. Ordinarily, BRCA2 fixes
breaks in the DNA of cancer cells caused by cancer drugs, so
dismantling BRCA2 leaves tumours more vulnerable to treatments.
"Cells have DNA repair pathways because they constantly
accumulate DNA damage, so fixing it is good for normal cells,
but DNA repair allows cancer cells to resist