LW - The Cancer Resolution? by PeterMcCluskey

The Nonlinear Library: LessWrong

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Welcome to The Nonlinear Library, where we use Text-to-Speech software to convert the best writing from the Rationalist and EA communities into audio. This is: The Cancer Resolution?, published by PeterMcCluskey on July 24, 2024 on LessWrong. Book review: The Cancer Resolution?: Cancer reinterpreted through another lens, by Mark Lintern. In the grand tradition of outsiders overturning scientific paradigms, this book proposes a bold new theory: cancer isn't a cellular malfunction, but a fungal invasion. Lintern spends too many pages railing against the medical establishment, which feels more like ax-grinding than science. I mostly agreed with his conclusions here, but mostly for somewhat different reasons than the ones he provides. If you can push through this preamble, you'll find a treasure trove of scientific intrigue. Lintern's central claim is that fungal infections, not genetic mutations, are the primary cause of cancer. He dubs this the "Cell Suppression theory," painting a picture of fungi as cellular puppet masters, manipulating our cells for their own nefarious ends. This part sounds much more like classical science, backed by hundreds of quotes from peer-reviewed literature. Those quotes provide extensive evidence that Lintern's theory predicts dozens of cancer features better than do the established theories. Older Theories 1. The DNA Theory (aka Somatic Mutation Theory): The reigning heavyweight, this theory posits that cancer results from an accumulation of genetic mutations in critical genes that control cell growth, division, and death. 2. Another old theory that still has advocates is the Metabolic Theory. This theory suggests that cancer is primarily a metabolic disease, characterized by impaired cellular energy production (the Warburg effect). It proposes that damage to mitochondria is a key factor in cancer development. I wrote a mixed review of a book about it. Lintern points out evidence that mitochondria are turned off by signals, not damaged. He also notes that tumors with malfunctioning mitochondria are relatively benign. Evidence Discrediting the DNA Theory The standard version of the DNA Theory predicts that all cancer cells will have mutations that affect replication, apoptosis, etc. Around 2008 to 2013, substantial genetic data became available for cancer cells. Lintern wants us to believe that this evidence fully discredits the DNA Theory. The actual evidence seems more complex than Lintern indicates. The strongest evidence is that they found cancers that seem to have no mutations. Almost as important is that the mutations that are found seem more randomly distributed than would be expected if they caused consistent types of malfunctions. Lintern's theory seems to explain all of the Hallmarks of Cancer, as well as a few dozen other features that seem to occur in all cancers. He argues that the DNA Theory does a poor job of explaining the hallmarks. DNA Theorists likely reject that characterization. They appear to have thought their theory explained the hallmarks back before the genetic data became available (mostly just positing mutations for each hallmark?). My guess is that they are busy adding epicycles to their theory, but the situation is complex enough that I'm having trouble evaluating it. He also points out that the DNA Theory struggles with Peto's Paradox (why don't larger animals get more cancer?), while his theory neatly sidesteps this issue. Additionally, mouse embryos formed from cancer cells showed no signs of cancer. Evidence of Fungi A key game-changer is the growing evidence of fungi in tumors. Until 2017, tumors were thought to be microbe-free. Now? We're finding fungi in all types of cancer, with tumor-specific fungal profiles. There's even talk of using fungal DNA signatures to distinguish cancer patients from healthy individuals. It's not a slam dunk for Lintern's theory, but it shifts the odds significantly. Medical Establishment Inertia It looks like people in the medical ...