Michel Aubé and colleagues from Université Laval and Institut national de santé publique in Québec, Canada have published findings suggesting that DDT’s main metabolite, 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (p,p’-DDE), could increase breast cancer progression. They suggest a mechanism whereby p,p’-DDE opposes the androgen signalling pathway that inhibits growth in hormone-responsive breast cancer cells.
The team tested the effect of p,p’-DDE on the proliferation of CAMA-1 cells, a human breast cancer cell line that expresses the estrogen receptor alpha (ERa) and the androgen receptor (AR), either with or without physiological concentrations of estrogens and androgens. They also assessed p,p’-DDE-induced modifications in cell cycle entry and the expression of sex-steroid dependent genes including ESR1 and CCND1, the latter coding for a key protein involved in cell proliferation.
When estrogens and androgens were present in the cell culture medium, increasing concentrations of p,p’-DDE accelerated the growth of CAMA-1 breast cancer cells. p,p’-DDE had a similar effect on the proliferation of MCF7-AR1 cells, an estrogen responsive cell line genetically engineered to over express the AR. Adding the potent androgen dihydrotestosterone together with estradiol to the cell culture medium decreased the recruitment of CAMA-1 cells in the S phase and the expression of ESR1 and CCND1, by comparison with cells treated with estradiol alone. These androgen-mediated effects were blocked with similar efficacy by p,p’-DDE and the potent antiandrogen hydroxyflutamide.
“Our results suggest that in addition to estrogenic compounds, which have been the main focus of researchers over the past decades, chemicals that block the AR could favour breast cancer progression” says Pierre Ayotte, who is leading the research team.
Ayotte’s team had previously linked concentrations of p,p’-DDE with tumour aggressiveness in women with breast cancer. They are now investigating the effect on breast cancer cell proliferation of a complex mixture of environmental chemicals, similar to that found in the blood of women, which comprises compounds with estrogenic and antiandrogenic activities.
Back to Nature: Palm oil plantations are being turned back into protected rainforest
21.03.2019 | Forschungsverbund Berlin e.V.
The inner struggle of the evening primrose: Chloroplasts are caught up in an evolutionary arms race
14.03.2019 | Max-Planck-Institut für Molekulare Pflanzenphysiologie
For the first time, physicists at the University of Basel have succeeded in measuring the magnetic properties of atomically thin van der Waals materials on the nanoscale. They used diamond quantum sensors to determine the strength of the magnetization of individual atomic layers of the material chromium triiodide. In addition, they found a long-sought explanation for the unusual magnetic properties of the material. The journal Science has published the findings.
The use of atomically thin, two-dimensional van der Waals materials promises innovations in numerous fields in science and technology. Scientists around the...
Flexible, organic and printed electronics conquer everyday life. The forecasts for growth promise increasing markets and opportunities for the industry. In Europe, top institutions and companies are engaged in research and further development of these technologies for tomorrow's markets and applications. However, access by SMEs is difficult. The European project SmartEEs - Smart Emerging Electronics Servicing works on the establishment of a European innovation network, which supports both the access to competences as well as the support of the enterprises with the assumption of innovations and the progress up to the commercialization.
It surrounds us and almost unconsciously accompanies us through everyday life - printed electronics. It starts with smart labels or RFID tags in clothing, we...
The human eye is particularly sensitive to green, but less sensitive to blue and red. Chemists led by Hubert Huppertz at the University of Innsbruck have now developed a new red phosphor whose light is well perceived by the eye. This increases the light yield of white LEDs by around one sixth, which can significantly improve the energy efficiency of lighting systems.
Light emitting diodes or LEDs are only able to produce light of a certain colour. However, white light can be created using different colour mixing processes.
Researchers led by Francesca Ferlaino from the University of Innsbruck and the Austrian Academy of Sciences report in Physical Review X on the observation of supersolid behavior in dipolar quantum gases of erbium and dysprosium. In the dysprosium gas these properties are unprecedentedly long-lived. This sets the stage for future investigations into the nature of this exotic phase of matter.
Supersolidity is a paradoxical state where the matter is both crystallized and superfluid. Predicted 50 years ago, such a counter-intuitive phase, featuring...
A stellar flare 10 times more powerful than anything seen on our sun has burst from an ultracool star almost the same size as Jupiter
17.04.2019 | Event News
15.04.2019 | Event News
09.04.2019 | Event News
26.04.2019 | Physics and Astronomy
26.04.2019 | Life Sciences
26.04.2019 | Physics and Astronomy