Grapes are 'edible sunscreen' according to a new study
A study says nature's candy can be a valuable supplement to sunblock.
- The skin of study participants who consumed lots of grapes developed an increased resistance to UV light.
- Grapes contain polyphenols, good stuff for repairing skin and fighting inflammation.
- After their grape adventure, biopsies revealed less skin-cell damage from UV light.
The study
<img class="rm-lazyloadable-image rm-shortcode" type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNTY2MTgyMy9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYyNDMxNjEwNX0.ZN4iBw442Ivwcdy3aw1GqOO2NTLUhukEhtDKfv3p4OU/img.jpg?width=980" id="702c7" width="1440" height="954" data-rm-shortcode-id="66e4586eac34ad3a1292ad419965f3cb" data-rm-shortcode-name="rebelmouse-image" />Credit: Maciej Serafinowicz/Unsplash/Big Think
<p>For the study, published in the <a href="https://www.jaad.org/article/S0190-9622(21)00183-3/pdf" target="_blank">Journal of the American Academy of Dermatology</a>, the researchers fed 19 healthy volunteers a powder of freeze-dried grapes for 14 days. This is the equivalent of 2.25 cups of grapes per day.</p><p>The participants' sensitivity to UV light was assessed before the trial period, and again afterward. Each individual's skin was assigned a Minimal Erythema Dose (MED) value — the threshold beyond which UVC radiation causes visible reddening to skin after 24 hours. After the test period, the amount of UV light required to redden each participant's skin was 74.8 percent greater than it had been before. This is the first study demonstrating this effect.</p><p>Biopsies also revealed fewer skin-cell deaths and fewer inflammatory markers. These slow down healing and may be linked to skin cancer.</p><p>The enhanced resistance to UV light came courtesy of an increase of <a href="https://en.wikipedia.org/wiki/Polyphenol" target="_blank">polyphenols</a> in their skin. Polyphenols are a naturally occurring family of compounds found in grapes, berries, and other fruits. They're also in products derived from them, such as wine, chocolate, tea, and legumes.</p><p>"Study results indicate that oral consumption of grapes has systemic beneficial effects in healthy adults," says Oak, citing prior research showing that polyphenols repair UV-ray damage, and that they can also reduce <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5055983/" target="_blank">inflammation</a>.</p><p>The researchers also found that a topical application of a grapeseed extract containing the polyphenol proanthocyanidins inhibited the formation of sunburn cells.</p>Avoiding skin cancer?
<p>An estimated one in five Americans develops skin cancer by age 70, with most cases being linked to sun exposure, including 90 percent of nonmelanoma skin cancers and 86 percent of melanomas.</p><p>The study finds early indications that grape consumption may also help a person avoid skin cancer, though these findings are just preliminary, cautions Oak, and require further investigation before a definitive conclusion may be drawn.</p><p>Principle investigator Craig Elmets, also of UAB, <a href="https://www.grapesfromcalifornia.com/wp-content/uploads/2021/02/20210204-nr-grape-consumption-may-protect-against-uv-damage-to-skin.pdf" target="_blank" rel="noopener noreferrer">tells</a> the California Table Grape Commission, "We saw a significant photoprotective effect with grape consumption and we were able to identify molecular pathways by which that benefit occurs — through repair of DNA damage and downregulation of proinflammatory pathways. Grapes may act as an edible sunscreen, offering an additional layer of protection in addition to topical sunscreen products."</p>Cancer cells hibernate to survive chemotherapy, finds study
Researchers discover that cancer cells go into hibernation to avoid chemotherapy effects.
- Cancer cells go into a state similar to hibernation when attacked by chemotherapy.
- The low-energy state is similar to diapause—the embryonic survival strategy of over a 100 species of mammals.
- Researchers hope to use these findings to develop new cancer-fighting therapies.
Cancer cells may go to into diapause, entering a drug-tolerant persister (DTP) state.
Credit: Cell
Michio Kaku: 3 mind-blowing predictions about the future
What lies in store for humanity? Theoretical physicist Michio Kaku explains how different life will be for your ancestors—and maybe your future self, if the timing works out.
- Carl Sagan believed humanity needed to become a multi-planet species as an insurance policy against the next huge catastrophe on Earth. Now, Elon Musk is working to see that mission through, starting with a colony of a million humans on Mars. Where will our species go next?
- Theoretical physicist Michio Kaku looks decades into the future and makes three bold predictions about human space travel, the potential of 'brain net', and our coming victory over cancer.
- "[I]n the future, the word 'tumor' will disappear from the English language," says Kaku. "We will have years of warning that there is a colony of cancer cells growing in our body. And our descendants will wonder: How could we fear cancer so much?"
Scientists stumble across new organs in the human head
New cancer-scanning technology reveals a previously unknown detail of human anatomy.
- Scientists using new scanning technology and hunting for prostate tumors get a surprise.
- Behind the nasopharynx is a set of salivary glands that no one knew about.
- Finding the glands may allow for more complication-free radiation therapies.
PSMA PET/CT technology
<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="79f0de836e4772af84272dd2bd0a10cc"><iframe type="lazy-iframe" data-runner-src="https://www.youtube.com/embed/RHAyoQF09X4?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span><p>PSMA PET/CT is a new combination of <a href="https://www.mayoclinic.org/tests-procedures/pet-scan/about/pac-20385078" target="_blank">PET scans</a> and <a href="https://www.mayoclinic.org/tests-procedures/ct-scan/about/pac-20393675" target="_blank">CT scans</a> that is believed to offer a more reliable means of locating prostate cancer metastasis. A <a href="https://www.cancer.gov/news-events/cancer-currents-blog/2020/prostate-cancer-psma-pet-ct-metastasis" target="_blank" rel="noopener noreferrer">study</a> published last spring suggests it may be the most accurate way to diagnose prostate cancer metastasis than any method previously available.</p><p>Prior to PSMA PET/CT, the primary way to look for metastatic prostate cancer was to image the body using x-ray-based CT scans and to perform bone scans, since bone is where prostate cancer often spreads. CT scans, however, often miss small tumors, and bone scans can generate false positives as a result of other damage or abnormalities that have nothing to do with prostate cancer.</p><p>PSMA PET/CT scans track the travels of an intravenously administered radioactive glucose tracer throughout the body. For hunting down prostate cancer, this tracer contains a molecule that binds to the <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1472940/" target="_blank">PSMA</a> protein that's present in large amounts in prostate tumors. The molecule is linked to a radioisotope, <a href="https://netrf.org/2018/11/13/gallium-68-scan-for-neuroendocrine-tumors/" target="_blank" rel="noopener noreferrer">gallium-68</a> (Ga-68).</p><p>In last spring's research, PSAM PET/CT was shown to be 27 percent more accurate than previous methods at finding metastases (92 percent accuracy as opposed to 65 percent). In addition, it was found to be much less likely to produce false positives, and it was particularly good at detecting tumors far removed from the prostate.</p>A good kind of avoidance behavior
<p>"Radiation therapy can damage the salivary glands," says Vogel, "which may lead to complications. Patients may have trouble eating, swallowing, or speaking, which can be a real burden."</p><p>The researchers looked back through the cases of 723 patients who had undergone radiation treatment, interested in seeing if inadvertent radiation of the tubarial glands was associated with the complications experienced by the patients. It turned out that this <em>was</em> the case: In cases where more radiation had been delivered to this area, patients did indeed report more in the way of complications of the type one would expect when salivary glands are radiated.</p><p>Now that we know the tubarial salivary glands exist, therapists can stay out of their way. Vogel says, "For most patients, it should technically be possible to avoid delivering radiation to this newly discovered location of the salivary gland system in the same way we try to spare known glands."</p><p>He's hopeful that that things may be about to get at least a bit better for cancer patients: "Our next step is to find out how we can best spare these new glands and in which patients. If we can do this, patients may experience less side effects which will benefit their overall quality of life after treatment."</p>Study calls out the genes that make cancer cells so hard to kill
Researchers from the University of Toronto published a new map of cancer cells' genetic defenses against treatment.
A moving target
<img class="rm-lazyloadable-image rm-shortcode" type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNDQzNjQ2Ny9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY1MDM3OTA0N30.z4u2eaulqRu8cslqqny8t9G7iaHr_DarbDJSFKLdDwI/img.jpg?width=980" id="21b22" width="1440" height="960" data-rm-shortcode-id="a3e5e81244ac86e6d916699b628732ac" data-rm-shortcode-name="rebelmouse-image" alt="IV drip" />Credit: Marcelo Leal/Unsplash
<p>Speaking to <a href="https://www.utoronto.ca/news/u-t-researchers-identify-genes-enable-cancer-evade-immune-system" target="_blank" rel="noopener noreferrer">U of T News</a>, lead author of the study molecular geneticist <a href="http://www.moleculargenetics.utoronto.ca/faculty/2014/9/30/jason-moffat" target="_blank" rel="noopener noreferrer">Jason Moffat</a> of the university's <a href="https://ccbr.utoronto.ca/donnelly-centre-cellular-and-biomolecular-research" target="_blank" rel="noopener noreferrer">Donnelly Centre for Cellular and Biomolecular Research</a> says, "Over the last decade, different forms of immunotherapy have emerged as really potent cancer treatments, but the reality is that they only generate durable responses in a fraction of patients and not for all tumor types."</p><p>There can be a significant degree of heterogeneity between cancer cells from human to human, and even within the same person, making the development of therapies maddeningly difficult. Attempting to address potential cancer-cell vulnerabilities across these variations is a life-or-death game of whack-a-mole.</p><p>"It's an ongoing battle between the immune system and cancer, where the immune system is trying to find and kill the cancer whereas the cancer's job is to evade that killing," says Moffat.</p>Mapping the mechanisms
<img class="rm-lazyloadable-image rm-shortcode" type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNDQzNjQ3Ni9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYyMjQ1OTM0MX0.HNtivrlU9VBYxcG9JaWKvPJ5RrBsgqd8Fw6ohfSpfh0/img.jpg?width=980" id="0faa6" width="1440" height="810" data-rm-shortcode-id="cdf7234ba2dcfcc273e3f15b6b1763a5" data-rm-shortcode-name="rebelmouse-image" />Illustration: genes (red, green, and blue spots within the nuclei of HeLa cells) artificially superimposed on images of multi-well plates.
Credit: National Cancer Institute/Unsplash
<p>Moffat and his colleagues decided to investigate and identify genes within cancer cells that help them defeat treatment. Co-lead author Keith Lawson of Moffat's lab explains that "it's important to not just find genes that can regulate immune evasion in one model of cancer, but what you really want are to find those genes that you can manipulate in cancer cells across many models because those are going to make the best therapeutic targets."</p><p>To accomplish this, the researchers, working with scientists at <a href="https://www.agios.com" target="_blank">Agios Pharmaceuticals</a> in Cambridge, Massachusetts, first exposed cells from breast, colon, kidney and skin cancer tumors to T cells in lab dishes. This established a baseline of their responses to treatment. Next, using CRISPR, the scientists went through the cells, exhaustively turning off one gene at a time to determine its role in immunotherapy resistance by comparing the cells' response to the T cells compared to their original baseline response.</p><p>The team identified 182 "core cancer intrinsic immune evasion genes" that affected the cells' response to T cells. The fact that some of the identified genes were already known to be involved in resistance provided the researchers with some confidence that they were on the right track.</p><p>Still, many of the genes they ID'ed had not been previously implicated. "That was really exciting to see because it means that our dataset was very rich in new biological information," says Lawson.</p>It's complicated
<p>Unfortunately, Moffat's research also makes clear that defeating cancer-cell resistance is not as simple as removing certain genes. It's true that when the team switched off some of the genes they'd identified, the cancer cells became more vulnerable to T cells, but on the other hand, removal of some other genes made the cancer cells more resistant.</p><p>There also appear to be relationships between multiple genes that complicate matters. </p><p>The team explored the manipulation of the genes that allow cancer cells to engage in <a href="https://en.wikipedia.org/wiki/Autophagy" target="_blank">autophagy</a>, the process by which cells clear out no-longer useful materials to facilitate speedy recovery from damage. Surprisingly, when the researchers deleted certain genes responsible for cancer cells' autophagy, they found the cells' resistance to T cells increased. Apparently, removing one autophagy gene strengthened another mutated autophagy gene.</p><p>"We found this complete inversion of gene dependency," said Moffat. "We did not anticipate this at all. What it shows us is that genetic context — what mutations are present — very much dictates whether the introduction of the second mutation will cause no effect, resistance or sensitivity to therapy."</p><p>There remains a long road ahead when it comes to unraveling cancer cells' resistance to immunotherapy. However, this new study presents a new map that can help scientists navigate what comes next.</p>