Scientists believe they may have found a new target for treating triple negative breast cancer one of the more difficult breast cancers to treat successfully and for which there is no targeted therapy at present.
Triple negative breast cancer (TNBC) is a cancer that does not express receptors for oestrogen (ER), progesterone (PR) or the human epidermal growth factor (HER2). It tends to be more aggressive, occurs more often in younger women, and is difficult to treat successfully as it lacks the receptors that currently available targeted therapies such as tamoxifen and trastuzumab (Herceptin) can home in on. Surgery, followed by chemotherapy, is the usual treatment.
Now researchers in Dublin (Ireland) have found that TNBC cells respond to compounds that disrupt the signalling processes of another receptor, EGFR (epidermal growth factor receptor), high levels of which are expressed in TNBC. In a presentation to the 22nd EORTC-NCI-AACR  Symposium on Molecular Targets and Cancer Therapeutics in Berlin today (Wednesday), Dr Patricia McGowan, a senior postdoctoral scientist at University College Dublin, said the compounds had reduced the growth of TNBC cells in the laboratory by up to 91%.
"As these cancers possess high levels of EGFR, we thought that they may be dependent on EGFR signalling," she said. "ADAMs (a disintegrin and metalloprotease) are enzymes that are involved in the activation of EGFR binding-proteins (i.e. ligands) during the signalling process, and so we thought that inhibiting them might be a potential therapeutic option for TNBC, either alone or in combination with drugs that target EGFR, such as gefitinib."
Dr McGowan and her colleagues tested gefitinib and a compound that specifically inhibits ADAM17 on breast cancer cell lines. The compound, known as TMI-002 (Pfizer), was similar to gefitinib in its ability to inhibit the growth of cancer cells. Gefitinib is not used in breast cancer treatment at present
|Contact: Emma Mason|
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