New findings on breast cancer resistant forms. Although breast cancer is one of the cancers that can be treated if diagnosed early, the chances of success are highly dependent upon cancer subtype. The study was conducted by researchers at the University of Manchester’s Paterson Institute for Cancer Research, and published in the journal PLoS One.The key to success in treating breast cancer
is to establish a correct diagnosis and appropriate therapeutic strategy. However, there are situations in which, once started treatment for a certain subtype of breast cancer, it becomes resistant to the drugs used.
Now researchers at the University of Manchester’s from Paterson Institute for Cancer Research have discovered a new marker of tamoxifen-resistant breast cancer. Tamoxifen is a drug used as adjunctive treatment with chemotherapy or radiation therapy to block tumor growth. This drug can be used only for cancers estrogen positive, ie for breast cancers that require estrogen to grow. It should be noted that estrogen positive breast cancer accounts for more than half of breast cancers. Tamoxifen is actually an estrogen receptor antagonist and is used in both pre-menopausal and post-menopausal women. In addition, tamoxifen is used for breast cancer prevention.Nevertheless, there are patients with breast cancer who do not respond to tamoxifen or develop resistance during treatment. Professor GÃ¶ran Landberg lead study said that although tamoxifen has been shown to be effective in the treatment of breast cancer, yet a third of patients cease to respond to initial treatment. He added that if they knew from the beginning what patients do not respond to treatment, they could receive proper treatment. It is therefore important the discovery of a marker to predict response to therapy.
Co-author Dr Susann Busch explained how they arrived at this discovery. They analyzed biopsies from 564 women with invasive breast cancer. Some of these received tamoxifen and some did not. It was found that fibroblasts, some cells from the connective tissue around the tumor, are responsible for resistance to tamoxifen. In fact it is a protein associated with fibroblasts, pERK, that causes tumors TO become resistant to tamoxifen.
The researchers made a comparison between the biopsies from 564 patients and seen that women with low levels of pERK did not respond to tamoxifen. Testing patients for pERK is not only time-saving but also money-saving.
Now researchers want to do more research to see the role of fibroblasts in tumor growth. Understanding these mechanisms may provide the basis for new therapeutic targets.