Resistant breast cancers responsive to Tamoxifen treatment

Sweden, February 24: Patients suffering from hard-to-beat cancers have a glimmer of hope coming their way from the researchers at Lund University, Malmo, Sweden. The anti-cancerdefine drug Tamoxifendefine coupled with a signalling protein Foxy-5 might prove to be effective in curing such cases.

The researchers, led by Caroline Ford, have looked into a method to re-establish the susceptibility of breast cancerdefine cells to Tamoxifendefine.

Tamoxifen therapy is commonly employed to inhibit cell proliferation and induce cell death in the patient by binding the drug to the oestrogen receptors of the cancer cells. But oestrogen receptors are not present on the cell surface in one-third of the breast cancer cases, thus rendering Tamoxifen ineffective.

Ford remarked, “Endocrine receptor alpha negative patients have lower survival rates than those with other types of breast cancer, probably because they have fewer therapeutic options. We are trying to give these patients a new therapeutic option.”

The main area of attention of Ford’s study was the signaling protein Wnt-5a. Ford said, “We think that Wnt-5a and its mimic, Foxy-5, act to increase the number of oestrogen receptors on the cancer cells.”

Moreover, Wnt-5a controls cell migration and improves cell adhesion, thus preventing the cancer cells from moving around in the body. This ensures that secondary tumors do not occur.

Ford’s group has demonstrated how Foxy-5, a hexa-peptide, mimics Wnt-5a signaling in the test-tube and hence brings back receptor expression in the negative oestrogen receptor cell lines.

More importantly, they have shown that these cell lines were then responsive to attack by Tamoxifen, which shows the therapeutic promise that this dual approach offers.

Ford said, “We have proved that Tamoxifen and Foxy-5 work together well in the lab and now we want try these them together in an animal model.”

Senior science information officer of the UK Cancer Research, Alison Ross, welcomed the research and added, “It’s encouraging that these preliminary results indicate that the Foxy-5 molecule may switch on the oestrogen receptor in breast cancers in mice, but it’s still a long way before we will know whether these approaches will work in humans, as most of the experiments were carried out in cells grown in the lab. But this new way of sensitising oestrogen-receptor negative breast cancers to the drug Tamoxifen is potentially exciting, as currently there are fewer treatment options available for these women.”