One of the greatest challenges current treatment options face is avoiding damage to healthy tissue while still targeting cancer. This applies to all treatments, but especially systemic therapies. The treatments we use are either localized, meaning they only impact one spot in the body, or systemic. Systemic therapies travel through the entire body. They’re great at targeting cancers that have spread because they reach all of the nooks and crannies of the body.

Systemic therapies include chemotherapies and various biological therapies, and these are by far the best options we have to treat late-stage cancer. But because they’re systemic, they have to pass by all the rest of our cells on the way to the cancer. That means that, because they’re, for the most part, non-specific, they can damage healthy cells throughout the body as they travel to a tumour.

Another issue that this poses is that, as treatments travel throughout the body, they disperse. The body is much larger than whatever container the drug is stored in, so as we put that drug into a larger vessel, being our bodies, the drug will spread out, and the concentration will be lower at any one location in the body.

A higher concentration of a drug in circulation means that any one spot in our bodies will also have a higher concentration, whether or not it has a tumour.

So how do we improve on traditional delivery methods? Well, what if we could just put the drug directly into the tumour? We wouldn’t have to worry as much about it circulating and harming other cells. We could use a lower concentration because it would already be high enough right where we need it. Is that possible?

Maybe. Some researchers are experimenting with a new way to deliver cancer-killing drugs right to the tumour’s front door: they’re called nanogels. Nanogels are exactly what they sound like. They’re really just a type of gel, like a hair gel, but really small. If you were to handle a nanogel, it would feel a lot like a liquid. That’s because the gel structure of nanogels is smaller than the wavelength of light — so we mix them with water.

Doing this helps solve a few problems in a really clever way. The first, and most important, is that by injecting it straight into the tumour, we can deliver a higher dose to the tumour with less in circulation. Less drug in circulation means less harm to healthy cells. For a treatment with as many side effects as chemotherapy, reducing the exposure of our healthy cells to these treatments would be a huge benefit. There’s also the chance that we would get more efficient tumour killing. That’s because when we administer chemotherapy, we often have to limit the dose to protect healthy cells. If we can keep the drug in one spot, only at the tumour site, we can increase the dosage without damaging healthy cells. More tumour killing while simultaneously damaging fewer healthy cells could be a life-changing and potentially life-saving advancement in the field of cancer treatment.

Nanogels also offer other neat advantages. For one, nanogels can be engineered to control how a drug is released. We can change how drugs are released over time and in different environments. That means we could pack a lot of chemotherapy into one dose with a nanogel and have it slowly release it over time. That would let us avoid having to administer several doses, and we could keep the tumour exposed to toxic chemotherapies for a longer period of time. We could also use nanogels that only release in highly acidic environments. Tumours tend to create more acidic environments because of their abnormal metabolism. Using a nanogel that only releases in acidic environments could help improve tumour specificity and avoid off-target effects. All of these effects have the potential to hugely improve a patient’s quality of life while maintaining the effect of cancer-killing drugs.

Systemic therapies are instrumental tools for treating late-stage cancer. Chemotherapies and various biological therapies have been foundational for decades and are still the most effective treatments we have for metastatic cancers. Despite this, one of the biggest challenges they face is off-target effects and damage to healthy cells. Because of the dangers these treatments pose to healthy cells, we’re forced to limit treatment regimens, which ultimately reduces their success. Nanogels are an innovative tool that could protect healthy cells while maintaining cancer-killing efficiency at the same time. With how strenuous and impactful the side effects of chemotherapies can be, this would be a huge advancement in the field of cancer treatment. To me, that is one of the most important aspects of cancer research.

At this point, we’re still waiting on research on nanogels. There have already been some clinical trials using nanogels, but they have yet to be approved for clinical use. One possible reason for that is that those trials only saw minor improvements in patient outcomes. Although nanogels are highly promising, we need more research to understand why they didn’t work as expected and how we can improve.

I hope you learned a little something today, but next week’s issue is going to get the blood bumping because we’re talking about angiogenesis — the way a tumour creates its own blood vessels.

See you next week!

If you missed last week’s letter, you can read “Only The Finest Quality” to learn a little more about tumour suppressors in cancer and how they work.