An innovative catalyst is reported for removing suspect carcinogen trichloroacetic acid (TCA) found in water after chlorination. SilverSil, a methyl-modified silica xerogel doped with Ag nanoparticles, shows remarkably high and stable activity as heterogeneous catalyst for the reductive dehalogenation of TCA with NaBH4 as reducing agent. Chloroacetic acid and acetic acid are the main products of the highly reproducible reductive dehalogenation. The low cost, high stability and ease of application of the SilverSil sol-gel catalyst to continuous processes open the route to the industrial uptake of SilverSil to free chlorinated waters from a probable human carcinogenic agent exerting significant genotoxic and cytotoxic effects.
Thyroid hormones (THs) regulate metabolism, proliferation, and genomic stability. Clinical studies have linked levothyroxine therapy with higher Oncotype DX Recurrence Scores in breast cancer (BC), suggesting a potential effect of thyroid hormone signaling on genomic risk. Here, we investigated the impact of triiodothyronine (T3) on DNA damage and repair pathways in estrogen receptor-positive T47D breast cancer and non-tumorigenic MCF10A cells. RNA sequencing revealed significant upregulation of RAD51 and enrichment of DNA repair pathways following 24 h T3 exposure. Consistently, T3 increased γH2AX and 53BP1 nuclear foci, indicating transient activation of the DNA damage response (DDR). These effects were transient, returning to baseline after 48 h, suggesting cellular adaptation. T3 also enhanced proliferation at 10 μM but inhibited growth at higher concentrations. Our findings indicate that acute exposure to T3 induces transient genomic stress, providing a potential mechanistic basis for the observed association between thyroid hormone therapy and increased BC recurrence risk.