Paclitaxel – a Product of Fungal Secondary Metabolism or an Artefact?^#

 

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Abstract

Taxol (common name: paclitaxel) is an extremely important component of drugs for the treatment of various cancers. Thirty years after the discovery of its effectiveness, a metabolic precursor of Taxol (10-deacetylbaccatin III) is still primarily extracted from needles of European yew trees. In order to meet the considerable demand, hopes were pinned on the possibilities of biotechnological production from the very beginning. In 1993, as if by chance, Taxol was supposedly discovered in fungi that grow endobiotically in yew trees. This finding aroused hopes of biotechnological use to produce fungal Taxol in large quantities in fermenters. It never came to that. Instead, a confusing flood of publications emerged that claimed to have detected Taxol in more and more eukaryotic and even prokaryotic species. However, researchers never reproduced these rather puzzling results, and they could certainly not be applied on an industrial scale. This paper will show that some of the misguided approaches were apparently based on a seemingly careless handling of sparse evidence and on at least questionable publications. Apparently, the desired gold rush of commercial exploitation was seductive. Scientific skepticism as an indispensable core of good scientific practice was often neglected, and the peer review process has not exerted its corrective effect. Self-critical reflection and more healthy skepticism could help to reduce the risk of such aberrations in drug development. This article uses this case study as a striking example to show what can be learned from the Taxol case in terms of research ethics and the avoidance of questionable research practices.

^# Parts of this article were published earlier in German in the journal “Laborjournal” LJ-Verlag GmbH & Co. KG Freiburg. Gärditz KF, Czesnick H. Taxol aus Pilzen – pharmazeutische Goldmine oder wissenschaftliche Ente? Laborjournal: 12–15. This current article contains additional and expanded research findings.

Publication History

Received: 02 February 2024

Accepted after revision: 05 April 2024

Article published online:
16 May 2024

© 2024. The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution-NonDerivative-NonCommercial License, permitting copying and reproduction so long as the original work is given appropriate credit. Contents may not be used for commecial purposes, or adapted, remixed, transformed or built upon. (https://creativecommons.org/licenses/by-nc-nd/4.0/)

Georg Thieme Verlag KG
Rüdigerstraße 14, 70469 Stuttgart, Germany

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