The Potential of Living Drugs: CAR T Cells and the Battle Against Cancer

Tuesday - April 23 2024, 19:14 UTC - 7 months ago

CAR T cells are bioengineered from a patient's own immune cells to fight cancer, and are showing promising results in previously untreatable blood cancers. However, exhaustion of these cells can lead to relapse and difficulty in fighting solid tumors. Recently, two studies discovered that boosting CAR T cells with the FOXO1 protein can help them resemble stem cells and improve their effectiveness in fighting cancer. This breakthrough could improve the design of CAR T cell therapies and benefit a wider range of patients, including those with autoimmune diseases, heart conditions, and viral infections.

In recent years, a new form of cancer treatment has emerged, holding promise for tackling previously untreatable blood cancers. Dubbed "living drugs," CAR T cells are bioengineered from a patient's own immune cells to make them better able to hunt and destroy cancer. This innovative approach is already bearing fruit, with six CAR T cell therapies approved by the FDA and over a thousand clinical trials underway. But as with any medical innovation, there are challenges that need to be addressed.

One of the key hurdles with CAR T cell therapy is the problem of cell exhaustion. Over time, the cells slowly dwindle in the body, leading to a decline in their effectiveness. This has dire consequences, as more than 50 percent of people who respond to CAR T therapies eventually relapse. In addition, CAR T cells have struggled to fight off solid tumors in breast, pancreatic, or deadly brain cancers. However, this month, two teams from the University of Pennsylvania and the Peter MacCallum Cancer Center in Australia have found a potential solution to this problem.

Both teams discovered that boosting CAR T cells with the FOXO1 protein could make them more similar to stem cells, known for their regenerative abilities. This "master switch" protein revs up metabolism and health in CAR T cells in mice, making them better able to fend off solid tumors. This promising result has led to optimism that this method could be used to improve the design of CAR T cell therapies and expand their benefits to a wider range of patients.

To fully understand the potential of CAR T cell therapy, it's important to comprehend how it works. Our immune system has a defense mechanism that naturally hunts down and eliminates infections and cancers in the body. T cells are a particular type of immune cell that recognize and latch onto enemy cells, thanks to a specific set of proteins that act as a cellular fingerprint.

However, tumors can be cunning, finding ways to evade this surveillance. In solid cancers, they can release chemicals that fight off immune cell defenders, enabling them to grow and spread. CAR T cells are engineered to override these barriers, using customized protein hooks targeting specific proteins on tumor cells. These supercharged T cells are grown in petri dishes and infused back into the body to fight the cancer.

Initially, CAR T cell therapy was a last-resort treatment for blood cancers. But it has now become a first-line therapy, used in the initial treatment of the disease. However, keeping the engineered cells alive in the body has been a challenge. With time, they stop dividing and become dysfunctional, allowing the cancer to relapse. This is where the breakthrough by the two teams with the FOXO1 protein has provided a glimmer of hope.

As research continues in the field of CAR T cell therapy, it's clear that the potential of this treatment goes beyond cancer. These living drugs could also be used to treat autoimmune diseases, heart conditions, and viral infections, including the notorious HIV. There are even suggestions that they could slow down the biological processes that contribute to aging. With ongoing advancements and discoveries, it's safe to say that CAR T cells are leading the charge in the battle against cancer and many other medical challenges.