A scientist works on a blood test in the Ajay Goel Lab, one of many labs that are developing blood tests to screen for different types of cancer.
Soon it may be possible to find different types of cancer earlier than ever through a simple blood test.
Among the many blood tests in development, researchers announced in July that they have developed one that may screen for early-onset colorectal cancer. The new potential screening tool, detailed in a study in the journal Gastroenterology, represents a major step in noninvasively and inexpensively detecting nonhereditary colorectal cancer at an earlier and more treatable stage.
In recent years, this type of cancer has been on the upswing in adults under age 50 and in those without a family history. In 2021, the American Cancer Society's revised guidelines began recommending that colorectal cancer screenings with colonoscopy begin at age 45. But that still wouldn’t catch many early-onset cases among people in their 20s and 30s, says Ajay Goel, professor and chair of molecular diagnostics and experimental therapeutics at City of Hope, a Los Angeles-based nonprofit cancer research and treatment center that developed the new blood test.
“These people will mostly be missed because they will never be screened for it,” Goel says. Overall, colorectal cancer is the fourth most common malignancy, according to the U.S. Centers for Disease Control and Prevention.
Goel is far from the only one working on this. Dozens of companies are in the process of developing blood tests to screen for different types of malignancies.
Some estimates indicate that between one-fourth and one-third of all newly diagnosed colorectal cancers are early-onset. These patients generally present with more aggressive and advanced disease at diagnosis compared to late-onset colorectal cancer detected in people 50 years or older.
To develop his test, Goel examined publicly available datasets and figured out that changes in novel microRNAs, or miRNAs, which regulate the expression of genes, occurred in people with early-onset colorectal cancer. He confirmed these biomarkers by looking for them in the blood of 149 patients who had the early-onset form of the disease. In particular, Goel and his team of researchers were able to pick out four miRNAs that serve as a telltale sign of this cancer when they’re found in combination with each other.
The blood test is being validated by following another group of patients with early-onset colorectal cancer. “We have filed for intellectual property on this invention and are currently seeking biotech/pharma partners to license and commercialize this invention,” Goel says.
He’s far from the only one working on this. Dozens of companies are in the process of developing blood tests to screen for different types of malignancies, says Timothy Rebbeck, a professor of cancer prevention at the Harvard T.H. Chan School of Public Health and the Dana-Farber Cancer Institute. But, he adds, “It’s still very early, and the technology still needs a lot of work before it will revolutionize early detection.”
The accuracy of the early detection blood tests for cancer isn’t yet where researchers would like it to be. To use these tests widely in people without cancer, a very high degree of precision is needed, says David VanderWeele, interim director of the OncoSET Molecular Tumor Board at Northwestern University’s Lurie Cancer Center in Chicago.
Otherwise, “you’re going to cause a lot of anxiety unnecessarily if people have false-positive tests,” VanderWeele says. So far, “these tests are better at finding cancer when there’s a higher burden of cancer present,” although the goal is to detect cancer at the earliest stages. Even so, “we are making progress,” he adds.
While early detection is known to improve outcomes, most cancers are detected too late, often after they metastasize and people develop symptoms. Only five cancer types have recommended standard screenings, none of which involve blood tests—breast, cervical, colorectal, lung (smokers considered at risk) and prostate cancers, says Trish Rowland, vice president of corporate communications at GRAIL, a biotechnology company in Menlo Park, Calif., which developed a multi-cancer early detection blood test.
These recommended screenings check for individual cancers rather than looking for any form of cancer someone may have. The devil lies in the fact that cancers without widespread screening recommendations represent the vast majority of cancer diagnoses and most cancer deaths.
GRAIL’s Galleri multi-cancer early detection test is designed to find more cancers at earlier stages by analyzing DNA shed into the bloodstream by cells—with as few false positives as possible, she says. The test is currently available by prescription only for those with an elevated risk of cancer. Consumers can request it from their healthcare or telemedicine provider. “Galleri can detect a shared cancer signal across more than 50 types of cancers through a simple blood draw,” Rowland says, adding that it can be integrated into annual health checks and routine blood work.
Cancer patients—even those with early and curable disease—often have tumor cells circulating in their blood. “These tumor cells act as a biomarker and can be used for cancer detection and diagnosis,” says Andrew Wang, a radiation oncologist and professor at the University of Texas Southwestern Medical Center in Dallas. “Our research goal is to be able to detect these tumor cells to help with cancer management.” Collaborating with Seungpyo Hong, the Milton J. Henrichs Chair and Professor at the University of Wisconsin-Madison School of Pharmacy, “we have developed a highly sensitive assay to capture these circulating tumor cells.”
Even if the quality of a blood test is superior, finding cancer early doesn’t always mean it’s absolutely best to treat it. For example, prostate cancer treatment’s potential side effects—the inability to control urine or have sex—may be worse than living with a slow-growing tumor that is unlikely to be fatal. “[The test] needs to tell me, am I going to die of that cancer? And, if I intervene, will I live longer?” says John Marshall, chief of hematology and oncology at Medstar Georgetown University Hospital in Washington, D.C.
Ajay Goel Lab
A blood test developed at the University of Texas MD Anderson Cancer Center in Houston helps predict who may benefit from lung cancer screening when it is combined with a risk model based on an individual’s smoking history, according to a study published in January in the Journal of Clinical Oncology. The personalized lung cancer risk assessment was more sensitive and specific than the 2021 and 2013 U.S. Preventive Services Task Force criteria.
The study involved participants from the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial with a minimum of a 10 pack-year smoking history, meaning they smoked 20 cigarettes per day for ten years. If implemented, the blood test plus model would have found 9.2 percent more lung cancer cases for screening and decreased referral to screening among non-cases by 13.7 percent compared to the 2021 task force criteria, according to Oncology Times.
The conventional type of screening for lung cancer is an annual low-dose CT scan, but only a small percentage of people who are eligible will actually get these scans, says Sam Hanash, professor of clinical cancer prevention and director of MD Anderson’s Center for Global Cancer Early Detection. Such screening is not readily available in most countries.
In methodically searching for blood-based biomarkers for lung cancer screening, MD Anderson researchers developed a simple test consisting of four proteins. These proteins circulating in the blood were at high levels in individuals who had lung cancer or later developed it, Hanash says.
“The interest in blood tests for cancer early detection has skyrocketed in the past few years,” he notes, “due in part to advances in technology and a better understanding of cancer causation, cancer drivers and molecular changes that occur with cancer development.”
However, at the present time, none of the blood tests being considered eliminate the need for screening of eligible subjects using established methods, such as colonoscopy for colorectal cancer. Yet, Hanash says, “they have the potential to complement these modalities.”
A space elevator would be cheaper and cleaner than using rockets
This is making space accessible to scientists, startups, and tourists who never could have afforded it previously, but the cheapest way to reach orbit might not be a rocket at all — it could be an elevator.
The space elevator
The seeds for a space elevator were first planted by Russian scientist Konstantin Tsiolkovsky in 1895, who, after visiting the 1,000-foot (305 m) Eiffel Tower, published a paper theorizing about the construction of a structure 22,000 miles (35,400 km) high.
This would provide access to geostationary orbit, an altitude where objects appear to remain fixed above Earth’s surface, but Tsiolkovsky conceded that no material could support the weight of such a tower.
We could then send electrically powered “climber” vehicles up and down the tether to deliver payloads to any Earth orbit.
In 1959, soon after Sputnik, Russian engineer Yuri N. Artsutanov proposed a way around this issue: instead of building a space elevator from the ground up, start at the top. More specifically, he suggested placing a satellite in geostationary orbit and dropping a tether from it down to Earth’s equator. As the tether descended, the satellite would ascend. Once attached to Earth’s surface, the tether would be kept taut, thanks to a combination of gravitational and centrifugal forces.
We could then send electrically powered “climber” vehicles up and down the tether to deliver payloads to any Earth orbit. According to physicist Bradley Edwards, who researched the concept for NASA about 20 years ago, it’d cost $10 billion and take 15 years to build a space elevator, but once operational, the cost of sending a payload to any Earth orbit could be as low as $100 per pound.
“Once you reduce the cost to almost a Fed-Ex kind of level, it opens the doors to lots of people, lots of countries, and lots of companies to get involved in space,” Edwards told Space.com in 2005.
In addition to the economic advantages, a space elevator would also be cleaner than using rockets — there’d be no burning of fuel, no harmful greenhouse emissions — and the new transport system wouldn’t contribute to the problem of space junk to the same degree that expendable rockets do.
So, why don’t we have one yet?
Tether troubles
Edwards wrote in his report for NASA that all of the technology needed to build a space elevator already existed except the material needed to build the tether, which needs to be light but also strong enough to withstand all the huge forces acting upon it.
The good news, according to the report, was that the perfect material — ultra-strong, ultra-tiny “nanotubes” of carbon — would be available in just two years.
“[S]teel is not strong enough, neither is Kevlar, carbon fiber, spider silk, or any other material other than carbon nanotubes,” wrote Edwards. “Fortunately for us, carbon nanotube research is extremely hot right now, and it is progressing quickly to commercial production.”Unfortunately, he misjudged how hard it would be to synthesize carbon nanotubes — to date, no one has been able to grow one longer than 21 inches (53 cm).
Further research into the material revealed that it tends to fray under extreme stress, too, meaning even if we could manufacture carbon nanotubes at the lengths needed, they’d be at risk of snapping, not only destroying the space elevator, but threatening lives on Earth.
Looking ahead
Carbon nanotubes might have been the early frontrunner as the tether material for space elevators, but there are other options, including graphene, an essentially two-dimensional form of carbon that is already easier to scale up than nanotubes (though still not easy).
Contrary to Edwards’ report, Johns Hopkins University researchers Sean Sun and Dan Popescu say Kevlar fibers could work — we would just need to constantly repair the tether, the same way the human body constantly repairs its tendons.
“Using sensors and artificially intelligent software, it would be possible to model the whole tether mathematically so as to predict when, where, and how the fibers would break,” the researchers wrote in Aeon in 2018.
“When they did, speedy robotic climbers patrolling up and down the tether would replace them, adjusting the rate of maintenance and repair as needed — mimicking the sensitivity of biological processes,” they continued.Astronomers from the University of Cambridge and Columbia University also think Kevlar could work for a space elevator — if we built it from the moon, rather than Earth.
They call their concept the Spaceline, and the idea is that a tether attached to the moon’s surface could extend toward Earth’s geostationary orbit, held taut by the pull of our planet’s gravity. We could then use rockets to deliver payloads — and potentially people — to solar-powered climber robots positioned at the end of this 200,000+ mile long tether. The bots could then travel up the line to the moon’s surface.
This wouldn’t eliminate the need for rockets to get into Earth’s orbit, but it would be a cheaper way to get to the moon. The forces acting on a lunar space elevator wouldn’t be as strong as one extending from Earth’s surface, either, according to the researchers, opening up more options for tether materials.
“[T]he necessary strength of the material is much lower than an Earth-based elevator — and thus it could be built from fibers that are already mass-produced … and relatively affordable,” they wrote in a paper shared on the preprint server arXiv.
After riding up the Earth-based space elevator, a capsule would fly to a space station attached to the tether of the moon-based one.
Electrically powered climber capsules could go up down the tether to deliver payloads to any Earth orbit.
Adobe Stock
Some Chinese researchers, meanwhile, aren’t giving up on the idea of using carbon nanotubes for a space elevator — in 2018, a team from Tsinghua University revealed that they’d developed nanotubes that they say are strong enough for a tether.
The researchers are still working on the issue of scaling up production, but in 2021, state-owned news outlet Xinhua released a video depicting an in-development concept, called “Sky Ladder,” that would consist of space elevators above Earth and the moon.
After riding up the Earth-based space elevator, a capsule would fly to a space station attached to the tether of the moon-based one. If the project could be pulled off — a huge if — China predicts Sky Ladder could cut the cost of sending people and goods to the moon by 96 percent.
The bottom line
In the 120 years since Tsiolkovsky looked at the Eiffel Tower and thought way bigger, tremendous progress has been made developing materials with the properties needed for a space elevator. At this point, it seems likely we could one day have a material that can be manufactured at the scale needed for a tether — but by the time that happens, the need for a space elevator may have evaporated.
Several aerospace companies are making progress with their own reusable rockets, and as those join the market with SpaceX, competition could cause launch prices to fall further.
California startup SpinLaunch, meanwhile, is developing a massive centrifuge to fling payloads into space, where much smaller rockets can propel them into orbit. If the company succeeds (another one of those big ifs), it says the system would slash the amount of fuel needed to reach orbit by 70 percent.
Even if SpinLaunch doesn’t get off the ground, several groups are developing environmentally friendly rocket fuels that produce far fewer (or no) harmful emissions. More work is needed to efficiently scale up their production, but overcoming that hurdle will likely be far easier than building a 22,000-mile (35,400-km) elevator to space.
This article originally appeared on Big Think, home of the brightest minds and biggest ideas of all time.
Overabundance of dissolved carbon dioxide poses a threat to marine life. A new system detects elevated levels of the greenhouse gases and mitigates them on the spot.
To date, though, methods for measuring CO2 in water at scale have been either intensely expensive, requiring fancy sensors that pump CO2 through membranes; or prohibitively complicated, involving a series of lab-based analyses. And that’s led to a bottleneck in efforts to remove carbon as well.
But recently, Boudinot cracked part of the code for measurement and mitigation, at least on a small scale. While the rest of the industry sorts out larger intricacies like getting ocean carbon markets up and running and driving carbon removal at billion-ton scale in centralized infrastructure, his decentralized method could have important, more immediate implications.
Specifically, for shellfish hatcheries, which grow seafood for human consumption and for coastal restoration projects. Some of these incubators for oysters and clams and scallops are already feeling the negative effects of excess carbon in water, and Vycarb’s tech could improve outcomes for the larval- and juvenile-stage mollusks they’re raising. “We’re learning from these folks about what their needs are, so that we’re developing our system as a solution that’s relevant,” Boudinot says.
Ocean acidification can wreak havoc on developing shellfish, inhibiting their shells from growing and leading to mass die-offs.
Ocean waters naturally absorb CO2 gas from the atmosphere. When CO2 accumulates faster than nature can dissipate it, it reacts with H2O molecules, forming carbonic acid, H2CO3, which makes the water column more acidic. On the West Coast, acidification occurs when deep, carbon dioxide-rich waters upwell onto the coast. This can wreak havoc on developing shellfish, inhibiting their shells from growing and leading to mass die-offs; this happened, disastrously, at Pacific Northwest oyster hatcheries in 2007.
This type of acidification will eventually come for the East Coast, too, says Ryan Wallace, assistant professor and graduate director of environmental studies and sciences at Long Island’s Adelphi University, who studies acidification. But at the moment, East Coast acidification has other sources: agricultural runoff, usually in the form of nitrogen, and human and animal waste entering coastal areas. These excess nutrient loads cause algae to grow, which isn’t a problem in and of itself, Wallace says; but when algae die, they’re consumed by bacteria, whose respiration in turn bumps up CO2 levels in water.
“Unfortunately, this is occurring at the bottom [of the water column], where shellfish organisms live and grow,” Wallace says. Acidification on the East Coast is minutely localized, occurring closest to where nutrients are being released, as well as seasonally; at least one local shellfish farm, on Fishers Island in the Long Island Sound, has contended with its effects.
The second Vycarb pilot, ready to be installed at the East Hampton shellfish hatchery.
Courtesy of Vycarb
Besides CO2, ocean water contains two other forms of dissolved carbon — carbonate (CO3-) and bicarbonate (HCO3) — at all times, at differing levels. At low pH (acidic), CO2 prevails; at medium pH, HCO3 is the dominant form; at higher pH, CO3 dominates. Boudinot’s invention is the first real-time measurement for all three, he says. From the dock at the Navy Yard, his pilot system uses carefully calibrated but low-cost sensors to gauge the water’s pH and its corresponding levels of CO2. When it detects elevated levels of the greenhouse gas, the system mitigates it on the spot. It does this by adding a bicarbonate powder that’s a byproduct of agricultural limestone mining in nearby Pennsylvania. Because the bicarbonate powder is alkaline, it increases the water pH and reduces the acidity. “We drive a chemical reaction to increase the pH to convert greenhouse gas- and acid-causing CO2 into bicarbonate, which is HCO3,” Boudinot says. “And HCO3 is what shellfish and fish and lots of marine life prefers over CO2.”
This de-acidifying “buffering” is something shellfish operations already do to water, usually by adding soda ash (NaHCO3), which is also alkaline. Some hatcheries add soda ash constantly, just in case; some wait till acidification causes significant problems. Generally, for an overly busy shellfish farmer to detect acidification takes time and effort. “We’re out there daily, taking a look at the pH and figuring out how much we need to dose it,” explains John “Barley” Dunne, director of the East Hampton Shellfish Hatchery on Long Island. “If this is an automatic system…that would be much less labor intensive — one less thing to monitor when we have so many other things we need to monitor.”
Across the Sound at the hatchery he runs, Dunne annually produces 30 million hard clams, 6 million oysters, and “if we’re lucky, some years we get a million bay scallops,” he says. These mollusks are destined for restoration projects around the town of East Hampton, where they’ll create habitat, filter water, and protect the coastline from sea level rise and storm surge. So far, Dunne’s hatchery has largely escaped the ill effects of acidification, although his bay scallops are having a finicky year and he’s checking to see if acidification might be part of the problem. But “I think it's important to have these solutions ready-at-hand for when the time comes,” he says. That’s why he’s hosting a second, 70-liter Vycarb pilot starting this summer on a dock adjacent to his East Hampton operation; it will amp up to a 50,000 liter-system in a few months.
If it can buffer water over a large area, absolutely this will benefit natural spawns. -- John “Barley” Dunne.
Boudinot hopes this new pilot will act as a proof of concept for hatcheries up and down the East Coast. The area from Maine to Nova Scotia is experiencing the worst of Atlantic acidification, due in part to increased Arctic meltwater combining with Gulf of St. Lawrence freshwater; that decreases saturation of calcium carbonate, making the water more acidic. Boudinot says his system should work to adjust low pH regardless of the cause or locale. The East Hampton system will eventually test and buffer-as-necessary the water that Dunne pumps from the Sound into 100-gallon land-based tanks where larvae grow for two weeks before being transferred to an in-Sound nursery to plump up.
Dunne says this could have positive effects — not only on his hatchery but on wild shellfish populations, too, reducing at least one stressor their larvae experience (others include increasing water temperatures and decreased oxygen levels). “If it can buffer water over a large area, absolutely this will [benefit] natural spawns,” he says.
No one believes the Vycarb model — even if it proves capable of functioning at much greater scale — is the sole solution to acidification in the ocean. Wallace says new water treatment plants in New York City, which reduce nitrogen released into coastal waters, are an important part of the equation. And “certainly, some green infrastructure would help,” says Boudinot, like restoring coastal and tidal wetlands to help filter nutrient runoff.
In the meantime, Boudinot continues to collect data in advance of amping up his own operations. Still unknown is the effect of releasing huge amounts of alkalinity into the ocean. Boudinot says a pH of 9 or higher can be too harsh for marine life, plus it can also trigger a release of CO2 from the water back into the atmosphere. For a third pilot, on Governor’s Island in New York Harbor, Vycarb will install yet another system from which Boudinot’s team will frequently sample to analyze some of those and other impacts. “Let's really make sure that we know what the results are,” he says. “Let's have data to show, because in this carbon world, things behave very differently out in the real world versus on paper.”