This new drug could break cancer’s resistance to treatment

A new experimental drug called CS18 may help break through cancer drug resistance by disabling several of the defenses tumors use to survive treatment. It strengthened existing therapies, restored drug sensitivity in resistant lung cancer cells, and slowed tumor growth in animal models. Researchers at Baylor College of Medicine have developed an experimental drug called CS18 that may help cancer treatments work against tumors that have become resistant to therapy. The study, published in Science Advances, provides early evidence supporting further investigation of CS18 as a possible future cancer treatment. "Therapeutic resistance is a main obstacle to achieve effective and durable cancer treatments," said corresponding author Dr. Weei-Chin Lin, professor of medicine – hematology and oncology and of molecular and cellular biology at Baylor.

"While some therapies are effective at the beginning, many patients eventually relapse because cancer cells can activate compensatory and convergent biological pathways that allow them to overcome the toxic effects of therapy, promoting survival." Rather than focusing on a single cancer pathway, the researchers set out to develop a drug that could interfere with a broader control center involved in several cancer-promoting processes at once. Their target was topoisomerase IIß-binding protein 1 (TopBP1), which the team describes as a 'biological switchboard' because it helps regulate multiple pathways associated with cancer growth and survival.