How Carcinogens Cause Cancer
Harold Varmus is an American Nobel Prize-winning scientist and the 14th and current Director of the National Cancer Institute, a post he was appointed to by President Barack Obama. He was a co-recipient (along with J. Michael Bishop) of the 1989 Nobel Prize in Physiology or Medicine for discovery of the cellular origin of retroviral oncogenes. He also serves as one of three co-Chairs of the President's Council of Advisors on Science and Technology.
From 1993 to 1999, he served as Director of the National Institutes of Health. As the NIH director, Varmus was credited with nearly doubling the research agency's budget. From 2000 to 2010, he served as President of Memorial Sloan-Kettering Cancer Center in New York City.
Beginning during his tenure as NIH director, Varmus has been a champion of an open access system for scientific papers, arguing that scientists should have control over the dissemination of their research rather than journal editors.
Siddhartha Mukherjee: So we’ve talked a little bit about the Cancer Genome. We’ve talked about the genetic changes, but I want to take one step back even before these genetic changes arise. Dr. Schwartzentruber, tell us what we know about how carcinogens cause cancer.
Doug Schwartzentruber: Well that is a challenging question because there are multiple ways for carcinogens to cause cancer and I probably should defer to some of the other panelists as well who have studied that much more than I have, but the obvious first step is how the environment which from the minute we’re born begins to interact and create feedback to say our normal cells that could then potentially be cancerous and maybe I'll stop at that point and lead into others.
Lewis Cantley: Well I can. I mean most carcinogens we think cause cancer by mutating DNA, but there are examples of carcinogens for example, forballesters [ph] which can cause skin cancers that almost certainly are to working through mutating DNA directly, although in the long run you always end up getting mutations in DNA. They are rather probably causing cells to grow at a higher rate and the higher the rate cells grow the more frequently they get mutations in DNA. Basically a cell has to go through a division cycle and make a daughter cell in order for a mutation to get locked in and that- But most really do it by directly damaging DNA, UV light, radiation directly damage the nucleotides in the DNA and many other chemical carcinogens interpolate into the DNA and at the time of cell division interfere with proper base replacement.
Harold Varmus: No, I agree entirely with this, but I would like to add two important points. First we as individuals grow up from a single cell and through many, many rounds of cell division many errors are going to occur because the ability to copy and distribute the three billion base pairs of DNA into daughter cells is an inherently error prone mechanism. We have ways to try to correct it, but nevertheless damage will occur and over the course of many cell doublings there will be damage that can be carcinogenic, so you don’t need to have external factors for cancer to arise. Cancer is probably part of our heritage. Genetic change is a good thing at the species level because we generate diversity throughout living systems.
The other point I would make is that not all carcinogens are UV light or radiation. Some of them are viruses and it’s very important to keep that in mind. It has been estimated that in developing countries for example maybe a third of cancers are caused by viruses. We actually have vaccines that are effective against some of those viruses. The human papillomavirus vaccine, the human hepatitis B virus vaccine can prevent a very large amount of cancer in those countries if the vaccines are made available, brought to patients, made affordable in poor countries. Cervical cancer is largely controlled in this country by pap smears, by early detection, and we only have about 3,000 deaths a year in this country, but in many parts of the world, India for example, and large parts of Africa, cervical cancer is the most common cause of death from cancer among women, and we now have the potential to reduce the incidence of that cancer by two-thirds using the human papillomavirus vaccine.
Seemingly every year there are new reports that something we consume or use on a daily basis is carcinogenic. But what exactly does that mean on a biological level?
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A study looks at the ingredients of a good scare.
Catching fear in a bottle<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNDYyNzg1Ny9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYyOTQwMTcyMn0.WtpJ1E_dhK2o09fBpKARynj4_p5NXeklgsXsbd7xr9w/img.jpg?width=980" id="8ff51" class="rm-shortcode" data-rm-shortcode-id="f10dd9188b173f4a36e85e9325507c6b" data-rm-shortcode-name="rebelmouse-image" />
Credit: Photo Boards/Unsplash<p>Previous studies have tracked physiological signs of fear arousal, but none have established a one-to-one correlation between that arousal and specific, actual fear events.</p><p>Andersen says that much of the research has been conducted in lab settings with weak fear stimuli, observing subjects as they experience things like scary videos. Scares in these situations tend to be weak and difficult to measure. Even harder to track in these situations is the link between enjoyment and fear. </p>
Eyes everywhere<iframe src="https://player.vimeo.com/video/109695164" width="100%" height="480" frameborder="0" scrolling="no" class="rm-shortcode" data-rm-shortcode-id="267ba87cfb8591ed5830499574d2272a"></iframe><p>Andersen and his colleagues conducted their experiments at <a href="https://dystopia.dk" target="_blank" rel="noopener noreferrer">Dystopia</a> Haunted House, a commercial attraction in Vejle, Denmark constructed in an old, run-down factory. The Recreational Fear Lab has a long-standing partnership with the spook shack.</p><p>They outfitted 100 volunteers with heart monitors and sent them on their terrifying way through the 50-room horror mansion. The facility incorporates a number of fright mechanisms including frequent jump scares in which a sudden threat takes a visitor by surprise.</p><p>Researchers surreptitiously observed their participants on closed-circuit video as they made their way through the attraction. They tracked each individual's scares, scoring them for intensity according to their visible reactions. After exiting the attraction, individuals self-reported their experiences in the haunted house.</p><p>Combining these self-reports with observer notes and each participant's heart-rate data gave the researchers subjective, behavioral, and physiological insights into the ways in which fear is experienced, and when it's a good thing or not.</p>
A pair of inverted U-shapes<p>In analyzing their data, the researchers saw two separate inverted u-shape curves. One depicted participants' enjoyment based on their self-reports and observed behavior. A similar u-curve was detected in their heart rates showing that just the right amount of heartbeat acceleration is associated with fun, but too much is too much. It's the terror Goldilocks zone.</p><p>Says Andersen, "If people are not very scared, they do not enjoy the attraction as much, and the same happens if they are too scared. Instead, it seems to be the case that a 'just-right' amount of fear is central for maximizing enjoyment."</p><p>The research suggests that being scared is enjoyable when it represents just a quick minor physiological deviation from one's normal state. When it goes on too long, however, or triggers too severe a physiological change, it becomes disturbing. Game over.</p><p>Andersen notes that this is not dissimilar to the factors known to make interpersonal play enjoyable: just the right amount of uncertainty and surprise. These are, maybe not coincidentally, also the ingredients of a successful joke.</p>
A meteorite that smashed into a frozen lake in Michigan may explain the origins of life on Earth, finds study.
- A new paper reveals a meteorite that crashed in Michigan in 2018 contained organic matter.
- The findings support the panspermia theory and could explain the origins of life on Earth.
- The organic compounds on the meteorite were well-preserved.
Meteor streaks through Michigan sky<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="80b7f30820153b35fc515592d7475f53"><iframe type="lazy-iframe" data-runner-src="https://www.youtube.com/embed/EPu2qnqMYBo?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span>
The meteorite that smashed into Strawberry Lake carried pristine extraterrestrial organic compounds.
Credit: Field Museum
A Mercury-bound spacecraft's noisy flyby of our home planet.
- There is no sound in space, but if there was, this is what it might sound like passing by Earth.
- A spacecraft bound for Mercury recorded data while swinging around our planet, and that data was converted into sound.
- Yes, in space no one can hear you scream, but this is still some chill stuff.
First off, let's be clear what we mean by "hear" here. (Here, here!)
Sound, as we know it, requires air. What our ears capture is actually oscillating waves of fluctuating air pressure. Cilia, fibers in our ears, respond to these fluctuations by firing off corresponding clusters of tones at different pitches to our brains. This is what we perceive as sound.
All of which is to say, sound requires air, and space is notoriously void of that. So, in terms of human-perceivable sound, it's silent out there. Nonetheless, there can be cyclical events in space — such as oscillating values in streams of captured data — that can be mapped to pitches, and thus made audible.
Image source: European Space Agency
The European Space Agency's BepiColombo spacecraft took off from Kourou, French Guyana on October 20, 2019, on its way to Mercury. To reduce its speed for the proper trajectory to Mercury, BepiColombo executed a "gravity-assist flyby," slinging itself around the Earth before leaving home. Over the course of its 34-minute flyby, its two data recorders captured five data sets that Italy's National Institute for Astrophysics (INAF) enhanced and converted into sound waves.
Into and out of Earth's shadow
In April, BepiColombo began its closest approach to Earth, ranging from 256,393 kilometers (159,315 miles) to 129,488 kilometers (80,460 miles) away. The audio above starts as BepiColombo begins to sneak into the Earth's shadow facing away from the sun.
The data was captured by BepiColombo's Italian Spring Accelerometer (ISA) instrument. Says Carmelo Magnafico of the ISA team, "When the spacecraft enters the shadow and the force of the Sun disappears, we can hear a slight vibration. The solar panels, previously flexed by the Sun, then find a new balance. Upon exiting the shadow, we can hear the effect again."
In addition to making for some cool sounds, the phenomenon allowed the ISA team to confirm just how sensitive their instrument is. "This is an extraordinary situation," says Carmelo. "Since we started the cruise, we have only been in direct sunshine, so we did not have the possibility to check effectively whether our instrument is measuring the variations of the force of the sunlight."
When the craft arrives at Mercury, the ISA will be tasked with studying the planets gravity.
The second clip is derived from data captured by BepiColombo's MPO-MAG magnetometer, AKA MERMAG, as the craft traveled through Earth's magnetosphere, the area surrounding the planet that's determined by the its magnetic field.
BepiColombo eventually entered the hellish mangentosheath, the region battered by cosmic plasma from the sun before the craft passed into the relatively peaceful magentopause that marks the transition between the magnetosphere and Earth's own magnetic field.
MERMAG will map Mercury's magnetosphere, as well as the magnetic state of the planet's interior. As a secondary objective, it will assess the interaction of the solar wind, Mercury's magnetic field, and the planet, analyzing the dynamics of the magnetosphere and its interaction with Mercury.
Recording session over, BepiColombo is now slipping through space silently with its arrival at Mercury planned for 2025.
A heated debate is occurring at the University of Miami.
- Students say they were identified with facial recognition technology after a protest at the University of Miami; campus police claim this isn't true.
- Over 60 universities nationwide have banned facial recognition; a few colleges, such as USC, regularly use it.
- Civil rights groups in Miami have called for the University of Miami to have talks on this topic.
Arthur Holland Michel: The Future of Surveillance Technology<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="8c330ab8c4df396f5313be796c0d96da"><iframe type="lazy-iframe" data-runner-src="https://www.youtube.com/embed/hIC-kaYcq34?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span><p>Americans don't always agree with that assessment, especially on college campuses. Over 60 universities—Harvard, MIT, and UCLA are on the list—have banned facial recognition. Of the few schools that utilize it, USC lets students enter their rooms via face scans; the software also ensures intruders cannot access buildings.</p><p>These are great uses of this technology. You could argue it's how any progress with our devices should work: in service of people. The problem, of course, is that those in power don't tend to stop when they have a little taste of the possibilities.</p><p>University of Miami is the <a href="https://www.forbes.com/sites/rachelsandler/2020/10/27/human-rights-groups-call-on-the-university-of-miami-to-ban-facial-recognition/#a11c8bf2965a" target="_blank">latest school</a> to be embroiled in a battle over facial recognition. The ACLU of Florida was joined by 21 other groups when requesting that the university hold an open forum so that students can express their concerns. A piece of their letter is below. </p><p>This call for action was inspired after a September incident in which students <a href="https://www.miaminewtimes.com/news/university-of-miami-tracked-protesters-with-video-surveillance-11712139" target="_blank">protested</a> returning for in-person classes during the pandemic. The students, concerned about their health, predominantly wore face masks. Still, a number of them were identified, leading to concerns that facial recognition was used. Campus police denied it—the chief even claimed the tech "doesn't work," though that notion <a href="https://www.cnn.com/2020/08/12/tech/face-recognition-masks/index.html" target="_blank">has been refuted</a>—yet civil liberties groups are worried that an invasion of privacy occurred.</p><p>Lia Holland, a member of the digital rights nonprofit <a href="https://www.fightforthefuture.org/news/2020-10-27-20-human-rights-organizations-call-on-university-of-miami-to-ban-facial-recognition-and-meet-f6f2119fd41b/" target="_blank">Fight for the Future</a>, wants answers from school administrators. </p><p style="margin-left: 20px;">"UMiami is struggling to answer to their creepy surveillance practices, and clarify whether they are using their own facial recognition system, or Florida's state facial recognition database."</p>
Credit: Pixel Shot / Adobe Stock<p>The police chief in question, David Rivero, claims overhead surveillance cameras provided identification at the protest. Yet speaking of another case involving facial-recognition software, he's <a href="https://www.miaminewtimes.com/news/university-of-miami-tracked-protesters-with-video-surveillance-11712139" target="_blank">on the record stating</a>, "We were able to [easily] identify and arrest him. We've [detected] a few bad guys that way."</p><p>The letter sent to the Board of Administrators <a href="https://www.fightforthefuture.org/news/2020-10-27-20-human-rights-organizations-call-on-university-of-miami-to-ban-facial-recognition-and-meet-f6f2119fd41b/" target="_blank">includes the following demands</a>: </p><ol><li>Issue a campus-wide policy banning non-personal use of facial recognition technology, and issue a statement that you have done so.</li><li>Immediately schedule an open forum with students and faculty/staff to discuss community concerns and clarify how student activists who participated in First Amendment protected protest activities were identified by campus police.</li><li>Immediately schedule a meeting with the UMiami Employee Student Alliance (UMESA) to address their COVID-19 safety concerns, the subject of the original protest.</li></ol><p>There's no doubt facial-recognition technology has a place in law enforcement. Victims of unsolved crimes are relieved when the perpetrators are brought to justice, regardless of the means. As Michel writes, some police forces are already surveilling large regions of their districts using the Gorgon Stare, a camera used from airplanes. Cameras are ubiquitous, and that's not going to change. </p>As a society, we need honest discussions regarding the application of surveillance. Nearly every citizen in China has <a href="https://www.cnet.com/news/in-china-facial-recognition-public-shaming-and-control-go-hand-in-hand/" target="_blank">already been logged</a> by facial recognition software, which has led to human rights abuses. While the stated intention of this tech by American police is pure, good intentions are known to pave the way...well, we know how that ends. <p>--</p><p><em>Stay in touch with Derek on <a href="http://www.twitter.com/derekberes" target="_blank">Twitter</a> and <a href="https://www.facebook.com/DerekBeresdotcom" target="_blank" rel="noopener noreferrer">Facebook</a>. His new book is</em> "<em><a href="https://www.amazon.com/gp/product/B08KRVMP2M?pf_rd_r=MDJW43337675SZ0X00FH&pf_rd_p=edaba0ee-c2fe-4124-9f5d-b31d6b1bfbee" target="_blank" rel="noopener noreferrer">Hero's Dose: The Case For Psychedelics in Ritual and Therapy</a>."</em></p>