Evaluating natural cancer treatments with Dr. Susan Horwitz

Can life change with a single letter in the mail? For my guest today, it did, and subsequently, so did the lives of millions of people with various forms of cancer, including breast cancer.

The letter in question came from the National Cancer Institute in 1977. The recipient was Dr. Susan Horwitz. The result: The creation of one of the most important cancer drugs that come from a natural product: Taxol, which is isolated from the yew plant. Today it is given to over a million patients.

As you’ll hear, Dr. Horwitz work – indeed, her incredible curiosity – didn’t end there. She has continued to investigate new cancer treatments that leverage natural products. Why?

Take triple negative breast cancer. By definition, it’s among the most challenging cancers to treat, comprising some 15-20 percent of all breast cancers. These aggressive tumors are treated with a cocktail of chemotherapy drugs. And although many patients have excellent survival following treatment, some patients with specific types of triple negative breast cancer have an incomplete response or even a relapse after a period of remission.

Making them even more difficult: Triple negative breast cancer tumors are frequently resistant – or become resistant – to a variety of drugs, increasing their potential to spread to other tissues – a process called metastasis.

To address these challenges, some scientists have screened novel chemotherapy drugs against triple negative cells to identify those with superior activity and less toxicity than conventional therapy. The goal: Find new therapeutic options -- new drug candidates – that they hope may lead to targeted therapies and new combination approaches to counter drug resistance and improve outcomes for patients with aggressive breast cancer.

How does this process work? What progress has been made? How hopeful do the outcomes seem?Dr. Horwitz is the one to ask.

Dr. Horwitz is a Distinguished University Professor and the Rose C. Falkenstein Chair in Cancer Research at the Albert Einstein College of Medicine in New York. Among her many honors: The Warren Alpert Foundation Prize from Harvard Medical School; American Cancer Society's Medal of Honor; the American Association for Cancer Research Award for Lifetime Achievement in Cancer Research. Most recently, Dr. Horwitz earned the 2019 Canada Gairdner Award, the country’s highest scientific prize. She has served as president of the American Association of Cancer Research, and has been a member of The National Academy of Sciences, the Institute of Medicine of the National Academies, [the American Academy of Arts and Sciences, and the American Philosophical Society,] and others. She also has been a BCRF Investigator since 2007.

This was a remarkable conversation, not only for the science discussed, but also the role Dr. Horwitz has played in its history.