A new scientific study led by Aristotle University of Thessaloniki highlights the global importance of yew tree populations, recognising them as valuable natural sources of compounds used in widely prescribed anticancer drugs.
The research focused on the European yew (Taxus baccata), a tall coniferous tree that grows in large populations in the mountains of northern Greece. Scientists examined nearly 100 trees across three ecosystems: the university forest of Taxiarchis in Halkidiki, Mount Olympus near the old monastery of Agios Dionysios, and Mount Vourinos between Kozani and Grevena. The study analysed genetic diversity, chemical composition, and epigenetic characteristics.
According to Professor Filippos Aravanopoulos, who coordinated the research, "Taxanes - natural chemical compounds produced by yew trees - are key components of drugs such as paclitaxel (Taxol), which is used to treat various forms of cancer." While these compounds are found in high concentrations in the bark, extracting them would kill the tree. Instead, researchers focus on substances in the needles. "The highest presence of these substances is found in fresh needles in spring," he told Voria.gr.
The study revealed significant differences among populations in the amount of anticancer taxanes produced, as well as seasonal fluctuations in their concentrations. Of the compounds analysed, 10-deacetylbaccatin III, a key precursor for the semi-synthetic manufacturing of paclitaxel, was identified as the most plentiful taxane in the needles, with the highest levels observed in the Olympus population.
Researchers also identified significant genetic diversity and clear population differentiation, suggesting that Greek yew forests are important reservoirs of genetic material. Additionally, elevated levels of DNA methylation were observed, an epigenetic mechanism associated with environmental adaptation, which the study indicates may signal resilience under climate change conditions.
The findings, published in the international scientific journal PLOS One, are described as the first time Greek yew populations have been assessed using such a comprehensive approach. The researchers suggest that the results could support future genetic improvement programmes, including the identification and clonal propagation of trees with higher taxane production, while preserving genetic diversity.
The study also emphasises the importance of protecting existing yew populations in Greece, which are described as scarce and fragmented, often consisting of fewer than 50 individuals. Recommended measures include expanding protected areas, establishing genetic resource conservation units, monitoring genetic diversity, banning logging, regulating grazing, and developing conservation programmes outside natural habitats.
Although yew cultivation is widespread in central and northern Europe, mainly for hedging, Professor Aravanopoulos noted that such efforts are limited in Greece. He added that “Cultivation and utilisation for pharmaceutical use is a very future-oriented plan." The research included partners like ELGO-DIMITRA and Fondazione Edmund Mach from Italy, with funding from national resources under the ESFA programme.
by Maria Ritzaleou - adapted from Greek by Vassia Barba
