Statins may help prevent breast cancer
Cholesterol-lowering statins may help to prevent breast cancer build up resistance to the gold standard treatment, a study has found.
Laboratory research carried out in the US suggests tumours are shielded against the effects of tamoxifen by cholesterol. The findings indicate that statins, which reduce cholesterol levels, may be useful for patients with tamoxifen-resistant breast cancer.
Alternatively new agents could be designed to block the excess production of cholesterol by breast cancer cells, say the researchers. Most breast cancers are fuelled by the female hormone, oestrogen. Tamoxifen reduces the sensitivity of breast cancer cells to oestrogen, but in some women it fails to work effectively.
The US investigators showed that breast cancer cells which are resistant to tamoxifen contain significantly higher amounts of cholesterol than those which are not. Cholesterol may protect breast tumours in two ways, said the scientists. One possibility was that it toughened up cell membranes, creating an impenetrable wall for drugs like tamoxifen. Another was that it affected the mitochondria – the cells’ “energy centres” – in a way which made it harder to kill the cells.
“High levels of mitochondrial cholesterol can delay or block cell death,” said Dr Rebecca Riggins, from Georgetown University in Washington DC, who presented the findings at the American Association for Cancer Research’s annual meeting in Denver, Colorado. “This is important because many cancer drugs, including tamoxifen, have been shown to induce breast cancer cell death through the mitochondria.”
The scientists are now looking at whether resistant breast cancer cells become re-sensitised to tamoxifen when cholesterol-production is blocked. “Our bet is that they do,” said Dr Riggins.
Source: Telegraph
