Lessons from the Yew Tree
A potent medicine for breast cancer originates in a toxic plant with a magical past.
In the heart of the tiny village of Fortingall, Scotland, stands an ancient yew tree—the Fortingall Yew—enveloped by the serene ambiance of a small churchyard cemetery. This tree, possibly the oldest in Europe, is a living testament to history, its roots entwined with centuries of Celtic lore. The scientific name of this yew tree is Taxus baccata, and it is an evergreen with a rich heritage. Its needles, bark, and seed cones contain toxic molecules, yet it's adorned with a singular non-toxic tissue—the fleshy red aril, encasing the seed. Historically, the yew's durable wood was instrumental in crafting musical instruments and the formidable English longbow.
You can join me on a visit to see the Fortingall Yew in this video, taken with National Geographic Explorer, Prof. Maria Fadiman:
Path from Plant to Medicine
The journey of the yew tree from a symbol of folklore to a cornerstone in modern medicine began in the 1950s with the United States National Cancer Institute's (NCI) initiative to discover new cancer therapies by tasking botanists to collect plant specimens from across the globe.
The turning point was the discovery of a compound in the Pacific yew (Taxus brevifolia), a relative of the English yew (Taxus baccata). Extracted in 1962 and isolated by Dr. Monroe Wall and Dr. Mansukh Wani in 1964, this compound, paclitaxel, marked a significant milestone in cancer treatment.
Paclitaxel's path to FDA approval was fraught with challenges, spanning three decades. Identified as a unique agent in arresting cancer cell growth by Dr. Susan Horwitz in 1977, its production initially faced obstacles due to the slow growth of yew trees. A breakthrough occurred when chemists discovered a method to synthesize paclitaxel from the toxic needles of the more common English yew. Today, it is produced at scale through fermentation processes. This innovation led to the mass production of paclitaxel (Taxol®), transforming it into one of the most widely used antitumor drugs.
Since the discovery of its antitumoral activity, Taxol® has been used to treat over one million patients, making it one of the most widely employed antitumoral drugs.—Source
Taxol demonstrated a unique ability to combat cancer by impeding cell division and inducing cancer cell death. Over time, Taxol® and its variations have become some of the most commonly used treatments for various types of cancer. These include breast cancer, ovarian cancer, a type of lung cancer known as non-small-cell lung carcinoma (NSCLC), Kaposi’s sarcoma (a cancer that often affects the skin), as well as cancers of the head and blood disorders like leucopenia.
Future Perspectives
The story of the yew tree and paclitaxel opens a window into the untapped potential of plant-derived cancer drugs. With over 374,000 plant species on Earth, and approximately 34,000 known for their medicinal properties, the opportunity for discovery is immense. A staggering 98% of these medicinal plants have yet to undergo thorough scientific evaluation. This vast, unexplored botanical world holds the promise of new, potent compounds that could revolutionize cancer treatment. The future of plant-derived cancer drugs lies in our continued exploration and scientific inquiry, blending traditional knowledge with modern pharmacology.
The Takeaway
The yew tree’s journey from a mystical symbol in Celtic lore to a source of one of the most effective cancer treatments highlights the profound connection between nature and medicine. This connection underscores the importance of preserving biodiversity and respecting traditional knowledge. As we continue to explore the depths of the plant kingdom, we may find more such 'magical' plants waiting to reveal their secrets.
Our willingness to learn from nature, combined with scientific rigor, could pave the way for breakthroughs in treating not just cancer but a myriad of other diseases. The legacy of the yew and its contribution to medicine is a powerful reminder of the wonders that nature holds and the potential benefits plants can bring to humanity.
Yours in health, Dr. Quave
Cassandra L. Quave, Ph.D. is a scientist, author, speaker, podcast host, wife, mother, explorer, and professor at Emory University School of Medicine. She teaches college courses and leads a group of research scientists studying medicinal plants to find new life-saving drugs from nature. She hosts the Foodie Pharmacology podcast and writes the Nature’s Pharmacy newsletter to share the science behind natural medicines. To support her effort, consider a paid or founding subscription, with founding members receiving an autographed 1st edition hardcover copy of her book, The Plant Hunter.
Available in hardcover, paperback, audio, and e-book formats!
