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Colombian science minister’s cancer claims spark controversy

Mabel Torres, the leader of Colombia’s new science agency, says she has created a fungus extract that can treat cancer.

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Casa de Nariño presidential palace in Bogota

Colombia’s vice-president has said that she supports the country's embattled science minister, Mabel Torres.Credit: Raul Arboleda/AFP/Getty

Colombian scientists celebrated the creation of the country’s first Ministry of Science, Technology and Innovation early last month as a step that would capture more resources for research and put science at the highest level of government. Yet, in just a few weeks that initial excitement has given way to anger and confusion over the appointment of the science minister Mabel Torres.

Torres, a mycologist from the Technological University of El Chocó in Quibdó, was little-known in the scientific community until her appointment on 30 December. Critics note that her publication record is limited — only 21 articles, most of them about the taxonomy of large, shell-like mushrooms of the genus Ganoderma, traditionally used in Chinese medicine to treat a variety of ailments.

But much of the controversy surrounding Torres relates to public claims she has made about the cancer-fighting properties of a Ganoderma extract that she makes herself. Torres, who has described the extract as “like a tea, a beverage”, says that she has given it to around 40 people with cancer — some of whom, she says, have entered into remission after taking the brew for a few months. The treatment was not given under the auspices of a clinical trial, nor was Torres’ methodology approved by a medical ethics committee. She has never submitted the results for publication in a peer-reviewed journal.

“I decided not to publish as an act of rebellion,” Torres said in an interview with El Espectador newspaper on 11 January. Days later, she promised on live radio that she would publish the data she has kept for four years, and insisted that she had done nothing improper. “To reject the scientific method would be to reject part of my essence,” she said. “The message I send is that we have to start recognizing and valuing other types of knowledge.”

Torres’ supporters see her as a committed minister who will be an advocate for some of Colombia’s most marginalized regions — including her own, El Chocó. But many researchers are questioning whether she is the right person to lead the long-awaited makeover of Colombian science. “She has exposed herself to the scrutiny of our community for not following the protocols that every scientist must follow,” says botanist Enrique Forero, president of the Colombian Academy of Exact, Physical and Natural Sciences in Bogotá. He fears that her appointment might embolden people peddling dubious or unproven medical treatments.

“Merchants of hopes and illusions are going to start appearing, producing remedies here and there,” Forero says. “And that’s very, very dangerous.”

Torres has not yet responded to a request for comment on Forero's claim.

Mixed evidence

When Torres gave people her Ganoderma extract, she did not perform steps that would be essential in a clinical trial, says Susana Fiorentino, an immunologist who studies the anti-tumour properties of Colombian folk medicine at the Pontifical Xavierian University in Bogotá. At no point did Torres isolate the chemical compounds contained in her extract to study how they affect cancer cells. Neither did she conduct tests in animals before moving on to people — as is standard, says Fiorentino.

Torres addressed the controversy in a statement issued by the science ministry on 18 January. “At no time have I simplistically proposed that this species [could] be the cure for cancer,” she wrote. “I haven’t offered a drug, let alone marketed it. I have rigorously observed the established ethical protocols for scientific experimentation in general and those that apply specifically in my disciplinary field.”

Torres has also said in interviews that her claims about Ganoderma’s cancer-fighting potential were misinterpreted by the media. She says that she never asked people to stop their cancer treatments and take her extract instead. Moreover, she says that she saw her Ganoderma extract as something closer to the traditional medicines that have been used for millennia in Asia or Colombia’s biodiverse El Chocó region, rather than scientific research. “I have complemented my training as a scientist with the analysis of ancestral knowledge” she said in her 18 January statement.

The published evidence behind Ganoderma’s anticancer properties is mixed at best. For example, a Cochrane review of five randomized controlled clinical trials totalling 373 participants found that one species of the fungus, Ganoderma lucidum, failed to shrink tumours, although G. lucidum extract did make people 27% more likely to respond to chemotherapy or radiotherapy1. However, most of the included studies were small and their methodology was weak, the Cochrane review found. (Torres has not specified which species of Ganoderma she uses in her extract.)

Going forward

Despite the ongoing controversy, Colombia’s vice-president, Marta Lucía Ramírez, said on 15 January that Torres would remain in her post as science minister. Torres herself has said as recently as 30 January that she has no plans to step down.

That does not satisfy her critics. “The most coherent thing to do is for her to resign,” says Fiorentino. But other prominent Colombian scientists are standing by the embattled science minister.

Torres “represents the best opportunity the country has to turn its eyes on the existing biodiversity in El Chocó”, tweeted Jaime Restrepo Cuartas, former director of Colombia’s former science agency, Colciencias.

“I understand the criticism [Torres] has received,” says Ricardo Torres Palma, a chemist at the University of Antioquia in Medellín. But he says that Torres is still a scientist — in contrast to many former leaders of Colciencias — so her appointment represents progress for Colombian researchers. “To help her,” says Torres Palma. “I think that’s our role now.”

doi: 10.1038/d41586-020-00235-w

References

  1. 1.

    Jin, X., Ruiz Beguerie, J., Sze, D.M.Y. & Chan, G.C.F. Cochrane Database Syst. Rev. https://doi.org/10.1002/14651858.CD007731.pub3 (2016).

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