Every cell has tiny power plants: mitochondria. They supply the energy for life. But once a cell turns cancerous, these plants work for the tumor, helping it grow. Scientists took curcumin, an ordinary yellow spice, and attached a special "address" to it that guides it straight into the mitochondria. There curcumin starts a small fire: it binds to a protective protein called TrxR, which normally puts out oxidative flare-ups. Without that protection, aggressive oxygen molecules pile up in the cell, and it launches its self-destruct program.
For the test, the researchers used Drosophila flies whose intestines had been switched to produce the Yorkie protein, which makes cells grow without stopping. The flies were fed curcumin with their food for two days. The tumor shrank by roughly half. Until now it was unclear whether this approach would work in a living organism. Now it is clear: it does. The flies lived longer, from 28 to 36 days. That means drugs can be designed to strike only diseased cells without touching healthy ones.
Drosophila thioredoxin reductase uses cysteine instead of selenocysteine, as in mammals, but retains high catalytic activity. This makes the fly enzyme a convenient model for testing inhibitors that do not depend on selenium.
Not published on arXiv. Here are its page, the PDF and the formalization: you can check it yourself, not only read our account.