Breast Cancer Drug Tests for Mesothelioma
By Kathy Cooke. 24th November 2016
A new study by The Royal College of Surgeons in Ireland has focused on the drug Tamoxifen as a potential therapy for mesothelioma.
How does the Tamoxifen drug work?
The drug is already used as a treatment for breast cancer and helps to fight the cancer by blocking cancer cells from using the estrogen they need to grow. Tamoxifen is a type of hormone treatment, also known as endocrine therapy and works on the whole body to block the effects of estrogen on the receptors.
It can help pre-menopausal women and post-menopausal women and may also be taken by men who have breast cancer.
Tamoxifen can be used after surgery and other treatments to reduce the risk of breast cancer returning and it reduces the risk of getting a new cancer in the other breast.
You usually take Tamoxifen for five years or longer, but some trials show taking it for 10 years may further reduce the risk of it coming back.
Tamoxifen and Pleural Mesothelioma
Some mesothelioma tumors also appear to rely on estrogen for growth, so the scientists proposed that Tamoxifen,
could be used to treat mesothelioma by modulating the estrogen receptors.
The scientists wanted to determine whether the drug could slow the growth of pleural mesothelioma and to see if it could improve the action of mesothelioma chemotherapy. So they tested tamoxifen in 4 different cells lines of mesothelioma in their laboratories. They were treated with a combination of Tamoxifen and the platinum-based drug Cisplatin, often used in chemotherapy for mesothelioma patients.
The results were encouraging. One of the Irish scientists, a molecular medicine specialist concluded that:
" Tamoxifen inhibited the growth of malignant pleural mesothelioma cells and also modulated their sensitivity to cisplatin "
However, instead of acting on the estrogen receptors in the ER-positive mesothelioma cell lines, Tamoxifen actually repressed the expression of cyclins, proteins associated with cell division. The result was an interruption of the normal cell cycle for these mesothelioma cells and an increase in apoptosis, the natural process of programmed cell death.
The scientist added that:
“ The ER-independent actions of Tamoxifen on malignant pleural mesothelioma cell proliferation and cell cycle
progression may have clinical benefits for a subset of patients with MPM ”