Chemotherapy hydrogel could fight skin cancer from the outside

Skin cancer might seem like the easiest cancer to deal with – after all, it's right there on the outside of the body, so removing it should be simple and safe, right?

Unsurprisingly the reality is not so simple and treatment often still requires chemotherapy, which is delivered intravenously and can cause a whole range of unpleasant side effects. Now, researchers have made the first steps towards a kind of chemo that can be "painted" onto the skin.

Researchers on the new study set out to develop a chemotherapy-loaded hydrogel that could be applied topically. The gel was designed to help the active cancer-fighting ingredients penetrate deep into the skin. In this case, that was the chemotherapy drug paclitaxel, which was wrapped in a surfactant and then a few phospholipid layers. The resulting nanoparticles are called "transfersomes," and the surfactants let them slip through the skin more easily where they can then get to work fighting the cancer cells.

In tests on mice, the researchers applied the gel onto melanoma tumors once a day, as well as giving the animals injections of paclitaxel every few days, while a second group received only the injections. After 12 days, the tumors in those that had received the gel were about half the size of those that were just getting injections of the drug, suggesting that the topical treatment was helping to slow down the cancer's growth.

As interesting as those results are, it's of course far too early to get too excited. The approach might not necessarily translate to humans, and there's not yet any data on whether the gel would ever be enough by itself, meaning injections might still be necessary. That said, the researchers believe they've made the first steps towards the goal of a chemo gel that patients could just rub on their skin at home by themselves.