Discovery could lead to new treatments for cancer and tumors, but probably not to any new diagnostic assays for clinical laboratories
Researchers at the University of Texas Southwestern (UTSW) Medical Center have reported discovery of “acid walls” that appear to protect various types of cancer tumors from attack by the body’s immune system cells. Though the discovery is not directly related to a biomarker for a clinical laboratory diagnostic test, the basic research will help scientists develop ways to address the tumor’s acid wall strategy for defeating the immune system.
The UT scientists made their discovery using an internally developed imaging technique that employs nanoparticle probes to detect levels of acidity in cells. The research, they suggest, “could pave the way for new cancer treatment approaches that alter the acidic environment around tumors,” according to a UTSW press release.
“This study revealed a previously unrecognized polarized extracellular acidity that is prevalent around cancer cells,” said lead study author Jinming Gao, PhD (above), Professor in the Harold C. Simmons Comprehensive Cancer Center and head of the Gao Lab at UT Southwestern Medical Center, in a press release. Gao believes the study “will lead to several new lines of research, such as studies to better understand how cancer cells polarize their acid excretion, how those cells can withstand the acidity level that kills CD8+ T cells, and how to inhibit acid excretion to allow T cells to better kill cancer cells,” the press release notes. (Photo copyright: University of Texas.)
Developing Acid Walls
As explained in the press release, scientists have long known that cancer cells are slightly more acidic than most healthy tissue. Gao and his team designed a nanoparticle known as pegsitacianine—a pH-sensitive fluorescent nanoprobe for image-guided cancer surgery—that disassembles and lights up when exposed to the acidic conditions in tumors.
However, “it was unclear why these nanoparticles fluoresced since a tumor’s acidity was thought to be too mild to trigger their activation,” the press release note.
To learn more, they used nanoparticle probes to illuminate a variety of individual cancer cells sampled from humans and mice, including lung, breast, melanoma, and glioblastoma, as well as tumor tissue. They discovered that the cancer cells secreted lactic acid—a waste product of digested glucose—at higher levels than previously known. The cells “pumped” the acid away from their malignant neighbors to form a protective “acid wall” around the tumor, the researchers noted in Nature Biomedical Engineering.
“Samples from human tumors showed that this acid wall was practically devoid of CD8+ T cells within the tumors, an immune cell type known to fight cancer,” the press release states. “When the researchers grew cancer cells and CD8+ T cells together in petri dishes that had been acidified to a 5.3 pH, the cancer cells were spared while the CD8+ T cells perished within three hours, suggesting that this severe acidity might thwart immune cell attack without harming the cancer cells.”
Gao’s team previously discovered that sodium lactate, the “conjugate base of lactic acid” as they describe it, increases the longevity of T cells and thus enhances their cancer-fighting capabilities. The researchers described the two molecules—lactate and lactic acid—as “Dr. Jekyll and Mr. Hyde,” and suggested that future therapies could seek to convert lactic acid to lactate.
“Gao noted that this discovery will lead to several new lines of research, such as studies to better understand how cancer cells polarize their acid excretion, how those cells can withstand the acidity level that kills CD8+ T cells, and how to inhibit acid excretion to allow T cells to better kill cancer cells,” the press release states.
Commercializing the Technology
Pegsitacianine was designed to aid cancer surgeons by illuminating the edges of solid metastatic tumors in real time during surgery, a 2023 UTSW Medical Center press release explains. About 24 hours prior to surgery, nanoprobes are delivered via IV. Then, the surgeon uses a near-infrared camera to visualize the cells.
UTSW has licensed pegsitacianine to OncoNano Medicine, a Dallas-area biotech startup launched to commercialize technologies from Gao Lab. Gao and his colleague Baran Sumer, MD, Professor and Chief of the Division of Head and Neck Oncology in UT Southwestern Medical Center’s Department of Otolaryngology and co-author on the study, both sit on OncoNano’s advisory board.
In January 2023, OncoNano announced that pegsitacianine had received Breakthrough Therapy Designation for Real-Time Surgical Imaging from the US Food and Drug Administration (FDA), which will fast-track the technology for development and regulatory review.
In a Phase II clinical trial published in the Annals of Surgical Oncology, the researchers tested the technology as part of cytoreductive surgery in patients with peritoneal metastases. However, a November 2023 UTSW press release noted that the technology is “tumor-agnostic and could potentially be used in other forms of cancer.” It is currently ready for Phase 3 trials, according to the OncoNano website.
More research and studies are needed to better understand this dynamic of cancer cells. Collectively, this research into cancer by different scientific teams is adding new insights into the way tumors originate and spread. At this time, these insights are not expected to lead to any new diagnostics tests that pathologists and clinical laboratories could use to detect cancer.
With further research, clinical laboratories may soon be performing macrobiotic testing to measure certain bacterial levels in patients’ gut bacteria
New insights from the University of Chicago (UChicago) into how human microbiota (aka, gut bacteria) play a role in food allergies has the potential to change the way a number of gastrointestinal health conditions are diagnosed and treated. This would give microbiologists and clinical laboratories a greater role in helping physicians diagnose, treat, and monitor patients with these health issues.
Past research has shown that certain gut bacteria can prevent antigens that trigger allergic reactions from entering the bloodstream. For example, Clostridium bacteria in the stomach produce a short-chain fatty acid known as butyrate, a metabolite that promotes the growth of healthy bacteria in the gut. This helps keep the microbiome in balance.
One way butyrate is created in the gut is through the fermentation of fiber. However, a lack of fiber in the diet can deplete the production of butyrate and cause the microbiome to be out of balance. When this happens, a state known as dysbiosis occurs that disrupts the microbiome and can lead to food allergies.
Without butyrate, the gut lining can become permeable and allow food to leak out of the gastrointestinal tract and into the body’s circulatory system. This reaction can trigger a potentially fatal anaphylactic response in the form of a food allergy. Thus, eating enough fiber is critical to the production of butyrate and to maintaining a balanced microbiome.
But today’s western diet can be dangerously low in soluble fiber. Therefore, the scientists at the University of Chicago have developed “a special type of polymeric molecule to deliver a crucial metabolite produced by these bacteria directly to the gut, where it helps restore the intestinal lining and allows the beneficial bacteria to flourish. … these polymers, called micelles, can be designed to release a payload of butyrate, a molecule that is known to help prevent food allergies, directly in the small and large intestines,” according to a UChicago news release.
This will be of interest to microbiologists, in particular. It’s another example of researchers connecting a specific species of bacteria in the human microbiome to a specific benefit.
“It’s very unlikely that butyrate is the only relevant metabolite, but the beauty of this platform is that we can make polymers with other microbial metabolites that could be administered in conjunction with butyrate or other therapies,” said Cathryn Nagler, PhD (above), Bunning Family Professor in the Biological Sciences Division and Pritzker School of Molecular Engineering at UChicago and a senior author of the study. “So, the potential for the polymer platform is pretty much wide open.” As further research validates these findings, clinical labs are likely to be doing microbiomic testing to monitor these therapies. (Photo copyright: University of Chicago.)
Restoring Butyrate in the Gut
One way to treat this anomaly has been through a microbiota transplant—also called a fecal biota transplant—where the administration of a solution of fecal matter is transplanted from a donor into the intestinal tract of the recipient. This transplant alters the recipient’s gut microbial composition to a healthier state, but it has had mixed results.
So, the UChicago researchers went in another direction (literally). They created an oral solution of butyrate and administered it to mice in the lab. The purpose of the solution was to thwart an allergic reaction when the mice were exposed to peanuts.
But there was a problem with their oral solution. It was repulsive.
“Butyrate has a very bad smell, like dog poop and rancid butter, and it also tastes bad, so people wouldn’t want to swallow it,” Shijie Cao, PhD, Postdoctoral Scientist at the Pritzker School of Molecular Engineering at UChicago and one of the researchers who worked on the project, told Medical News Today.
The researchers developed a new configuration of polymers that masked the butyrate. They then delivered these polymer micelles directly into the digestive systems of mice that lacked healthy gut bacteria or a proper gut linings.
The treatment restored the microbiome by increasing the production of peptides that obliterate harmful bacteria. This allowed more of the beneficial butyrate-producing bacteria to emerge, which protected the mice from an anaphylactic reaction to peanuts and even reduced the symptom severity in an ulcerative colitis model.
“We were delighted to see that our drug both replenished the levels of butyrate present in the gut and helped the population of butyrate-producing bacteria to expand,” said Cathryn Nagler, PhD, Bunning Family Professor in the Biological Sciences Division and Pritzker School of Molecular Engineering at the University of Chicago and a senior author of the study, in the press release. “That will likely have implications not only for food allergy and inflammatory bowel disease (IBD), but also for the whole set of non-communicable chronic diseases that have been rising over the last 30 years, in response to lifestyle changes and overuse of antibiotics in our society.”
Future Benefits of UChicago Treatment
According to data from the Asthma and Allergy Foundation of America, about 20 million Americans suffered from food allergies in 2021. This includes approximately 16 million (6.2%) of adults and four million (5.8%) of children. The most common allergens for adults are shellfish, peanuts, and tree nuts, while the most common allergens for children are milk, eggs, and peanuts.
The best way to prevent an allergic reaction to a trigger food is strict avoidance. But this can be difficult to ensure outside of the home. Therefore, scientists are searching for ways to prevent food allergies from happening in the first place. The micelle technology could be adapted to deliver other metabolites and molecules which may make it a potential platform for treating allergies as well as other inflammatory gastrointestinal diseases.
“It’s a very flexible chemistry that allows us to target different parts of the gut,” said Jeffrey Hubbell, PhD, Eugene Bell Professor in Tissue Engineering and Vice Dean and Executive Officer at UChicago’s Pritzker School of Molecular Engineering and one of the project’s principal investigators, in the UChicago news release. “And because we’re delivering a metabolite like butyrate, it’s antigen-agnostic. It’s one agent for many different allergic indications, such as peanut or milk allergies. Once we begin working on clinical trials, that will be a huge benefit.”
Nagler and Hubbell have co-founded a company called ClostraBio to further the development of butyrate micelles into a commercially available treatment for peanut and other food allergies. They hope to begin clinical trials within the next 18 months and expand the technology to other applications as well.
Further research and clinical trials are needed to prove the validity of using polymer micelles in the treatment of diseases. But it is possible that clinical laboratories will be performing microbiomic testing in the future to help alleviate allergic reactions to food and other substances.
Wearable microneedle sensors that track multiple biomarkers in interstitial fluid are finding their way into chronic disease monitoring and sample collecting for clinical laboratory testing
Wearable devices that replace finger sticks and blood draws for monitoring biomarkers of chronic diseases such as diabetes are the holy grail of non-invasive (or at least minimally invasive) technologies that collect specimens for clinical laboratory testing.
Now, in their quest for alternatives to invasive phlebotomy blood draws, engineers at University of California San Diego’s (UCSD) Center for Wearable Sensors have added their own wearable device to the mix. The scientists developed a “lab-on-the-skin” multi-tasking microneedle sensor that monitors multiple biomarkers simultaneously, according to a UCSD news release.
“This is like a complete lab on the skin,” said Joseph Wang, PhD (above), Distinguished Professor of Nanoengineering at UC San Diego and Director of UCSD’s Center of Wearable Sensors, in a news release. “It is capable of continuously measuring multiple biomarkers at the same time, allowing users to monitor their health and wellness as they perform their daily activities.” UC San Diego’s microneedle patch for monitoring biomarkers of disease certainly would be popular with patients who must regularly undergo painful blood draws for clinical laboratory testing. (Photo copyright: UC San Diego.)
Advantage of Monitoring Multiple Biomarkers in Real Time
While current glucose monitors on the market only measure glucose, the UCSD wearable device also monitors alcohol and lactate, providing other additional information to diabetics when engaged in activities that affect those biomarkers.
For example, UCSD’s microneedle sensor allows diabetics to monitor their glucose level when drinking alcohol, which can lower glucose levels. Additionally, monitoring lactate while exercising also could be beneficial since physical activity influences the body’s ability to regulate glucose.
“With our wearable, people can see the interplay between their glucose spikes or dips with their diet, exercise, and drinking of alcoholic beverages. That could add to their quality of life as well,” said Farshad Tehrani, a nanoengineering PhD graduate researcher in Wang’s lab at UCSD and one of the co-first authors of the study, in the news release.
UC San Diego’s wearable microneedle patch (above) is about the size of a stack of six quarters and simultaneously monitors glucose, alcohol, and lactate levels continuously. It affixes to the skin through a patch of microneedles each about one-fifth the width of a human hair. The microneedles barely penetrate the surface of the skin to sample biomolecules in the interstitial fluid and are not painful. The quarter-sized patch is worn on the upper arm and transmits its data to a smartphone app. The microneedle patch is disposable, and the reusable electronic case is rechargeable using an off-the-shelf wireless charging pad. (Photo copyright: Laboratory for Nanobioelectronics/UC San Diego.)
Other Microneedle Wearable Monitoring Patches
The quest for a painless alternative to in-patient blood draws for many clinical laboratory tests has been ongoing worldwide for years.
In “Researchers Develop ‘Smart’ Microneedle Adhesive Bandage System for Monitoring Sodium, Glucose, pH, and More,” Dark Daily reported on a proof-of-concept study conducted by scientists from Israel and China who developed a “smart” microneedle adhesive bandage that measures and monitors in real time three critical biomarkers that currently require invasive blood draws for medical laboratory tests commonly performed on patients in hospitals.
While further research and validation of studies are needed before UC San Diego’s wearable microneedle sensor patch can be deployed to monitor chronic diseases, it is in good company. Diabetics and other suffers of similar chronic diseases can look forward to a future where they can monitor their health conditions in real time without the need for invasive blood draws and clinical laboratory testing.
Columbia University’s MediSCAPE enables surgeons to examine tissue structures in vivo and a large-scale clinical trial is planned for later this year
Scientists at Columbia University in New York City have developed a high-speed 3D microscope for diagnosis of cancers and other diseases that they say could eventually replace traditional biopsy and histology “with real-time imaging within the living body.”
The technology is designed to enable in situ tissue analysis. Known as MediSCAPE, the microscope is “capable of capturing images of tissue structures that could guide surgeons to navigate tumors and their boundaries without needing to remove tissues and wait for pathology results,” according to a Columbia University news story.
“The way that biopsy samples are processed hasn’t changed in 100 years, they are cut out, fixed, embedded, sliced, stained with dyes, positioned on a glass slide, and viewed by a pathologist using a simple microscope. This is why it can take days to hear news back about your diagnosis after a biopsy,” said Hillman in the Columbia news story.
“Our 3D microscope overcomes many of the limitations of prior approaches to enable visualization of cellular structures in tissues in the living body. It could give a doctor real-time feedback about what type of tissue they are looking at without the long wait,” she added in I News.
Hillman’s team previously used the technology—originally dubbed SCAPE for “Swept Confocally Aligned Planar Excitation” microscopy—to capture 3D images of neurological activity in living samples of worms, fish, and flies. In their recent study, the researchers tested the technology with human kidney tissue, a human volunteer’s tongue, and a mouse with pancreatic cancer.
“This was something I didn’t expect—that I could actually look at structures in 3D from different angles,” said nephropathologist and study co-author Shana M. Coley, MD, PhD (above), Director, Transplant Translational Research and Multiplex Imaging Center at Arkana Laboratories, in the Columbia news story. At the time of the Columbia study, Coley was an assistant professor at Columbia University and a renal pathologist at the Columbia University Medical Center. “We found many examples where we would not have been able to identify a structure from a 2D section on a histology slide, but in 3D we could clearly see its shape. In renal pathology in particular, where we routinely work with very limited amounts of tissue, the more information we can derive from the sample, the better for delivering more effective patient care,” she added. (Photo copyright: Arkana Laboratories.)
How MediSCAPE Works
Unlike traditional 3D microscopes that use a laser to scan tiny spots of a tissue sample and then assemble those points into a 3D image, the MediSCAPE 3D microscope “illuminates the tissue with a sheet of light—a plane formed by a laser beam that is focused in a special way,” I News reported.
The MediSCAPE microscope thus captures 2D slices which are rapidly stacked into 3D images at a rate of more than 10 volumes per second, according to I News.
“One of the first tissues we looked at was fresh mouse kidney, and we were stunned to see gorgeous structures that looked a lot like what you get with standard histology,” said optical systems engineer and the study’s lead author, Kripa Patel, PhD, in the Columbia news story. “Most importantly, we didn’t add any dyes to the mouse—everything we saw was natural fluorescence in the tissue that is usually too weak to see.
“Our microscope is so efficient that we could see these weak signals well,” she continued, “even though we were also imaging whole 3D volumes at speeds fast enough to rove around in real time, scanning different areas of the tissue as if we were holding a flashlight.”
A big advantage of the technology, Hillman noted, is the ability to scan living tissue in the body.
“Understanding whether tissues are staying healthy and getting good blood supply during surgical procedures is really important,” she said in the Columbia news story. “We also realized that if we don’t have to remove (and kill) tissues to look at them, we can find many more uses for MediSCAPE, even to answer simple questions such as ‘what tissue is this?’ or to navigate around precious nerves. Both of these applications are really important for robotic and laparoscopic surgeries, where surgeons are more limited in their ability to identify and interact with tissues directly.”
Clinical Trials and FDA Clearance
Early versions of the SCAPE microscopes were too large for practical use by surgeons, so Columbia post-doctoral research scientist Wenxuan Liang, PhD, co-author of the study, helped the team develop a smaller version that would fit into an operating room.
Later this year, the researchers plan to launch a large-scale clinical trial, I News reported. The Columbia scientists hope to get clearance from the US Food and Drug Administration (FDA) to develop a commercialized version of the microscope.
“They will initially seek permission to use it for tumor screening and guidance during operations—a lower and easier class of approval—but ultimately, they hope to be allowed to use it for diagnosis,” Liang wrote.
Charles Evans, PhD, research information manager at Cancer Research UK, told I News, “Using surgical biopsies to confirm a cancer diagnosis can be time-consuming and distressing for patients. And ensuring all the cancerous tissue is removed during surgery can be very challenging unaided.”
He added, “more work will be needed to apply this technique in a device that’s practical for clinicians and to demonstrate whether it can bring benefits for people with cancer, but we look forward to seeing the next steps.”
Will the Light Microscope be Replaced?
In recent years, research teams at various institutions have been developing technologies designed to enhance or even replace the traditional light microscope used daily by anatomic pathologists across the globe.
And digital scanning algorithms for creating whole-slide images (WSIs) that can be analyzed by pathologists on computer screens are gaining in popularity as well.
Such developments may spark a revolution in surgical pathology and could signal the beginning of the end of the light microscope era.
Surgical pathologists should expect to see a steady flow of technologically advanced systems for tissue analysis to be submitted to the FDA for pre-market review and clearance for use in clinical settings. The light microscope may not disappear overnight, but there are a growing number of companies actively developing different technologies they believe can diagnose either or both tissue and digital images of pathology slides with accuracy comparable to a pathologist.
Skin patch technologies could enable clinical laboratories to monitor patients’ vitals and report to medical professionals in real time
Pathologists and clinical laboratory leaders have read many Dark Daily ebriefings on the development of skin patches over the years that do everything from monitoring fatigue in the military to being a complete lab-on-skin technology. Now, researchers at the University of California San Diego (UCSD) have developed a wearable patch that can monitor cardiovascular signals and other various biochemical levels in the body simultaneously.
The researchers believe there is enormous potential for such a patch in helping patients monitor conditions such as hypertension or diabetes. They also foresee a scenario where the patch could be used in settings where vitals must be constantly monitored. They hope to develop future versions of the patch that can detect more biomarkers within the body.
“This type of wearable would be very helpful for people with underlying medical conditions to monitor their own health on a regular basis,” Lu Yin, a PhD student and co-first author of the study, told New Atlas. “It would also serve as a great tool for remote patient monitoring, especially during the COVID-19 pandemic when people are minimizing in-person visits to the clinic,” she added.
Combining Precision Medicine with Telehealth and the Internet of Things
About the size of a postage stamp and consisting of stretchy polymers that conform to the skin, the UCSD patch monitors blood pressure and contains sensors that measure different biochemical levels in the body, such as:
The sensors are carefully arranged on the patch to eliminate interference between the signals, noted a UCSD press release.
In their published research, the UCSD researchers wrote of their new skin patch monitoring device, “Intertwined with concepts of telehealth, the internet of medical things, and precision medicine, wearable sensors offer features to actively and remotely monitor physiological parameters. Wearable sensors can generate data continuously without causing any discomfort or interruptions to daily activity, thus enhancing the self-monitoring compliance of the wearer, and improving the quality of patient care.” (Photo copyright: University of California San Diego.)
“Each sensor provides a separate picture of a physical or chemical change. Integrating them all in one wearable patch allows us to stitch those different pictures together to get a more comprehensive overview of what’s going on in our bodies,” said Sheng Xu, PhD, Principle Investigator, Xu Research Group at UCSD, Assistant Professor in the Department of NanoEngineering Department, and a co-first author of the study, in the press release.
The UCSD researchers developed their skin patch to monitor specific biomarkers that can affect blood pressure.
“Let’s say you are monitoring your blood pressure and you see spikes during the day and think that something is wrong,” co-first author Juliane Sempionatto, PhD, a postdoctoral researcher at California Institute of Technology (Caltech) and co-first author of the study, told New Atlas. “But a biomarker reading could tell you if those spikes were due to an intake of alcohol or caffeine. This combination of sensors can give you that type of information,” she added.
The blood pressure sensor sits near the center of the patch and consists of a set of small transducers welded to the patch via a conductive link. Voltage applied to the transducers send ultrasound waves through the body which bounce off arteries and create echoes that are detected by the sensor and converted into an accurate blood pressure reading.
The chemical sensor releases the drug pilocarpine into the skin to induce sweat and then measures the chemicals contained in the sweat to provide readings of certain biochemical levels.
The glucose sensor located in the patch emits a mild electrical current to the body that stimulates the release of interstitial fluid and then reads the glucose level in that fluid.
“The novelty here is that we take completely different sensors and merge them together on a single small platform as small as a stamp,” Joseph Wang, D.Sc, SAIC Endowed Chair, Distinguished Professor of NanoEngineering, Director of the Center for Wearable Sensors at UCSD, and co-author of the study told New Atlas. “We can collect so much information with this one wearable and do so in a non-invasive way, without causing discomfort or interruptions to daily activity.” (Photo copyright: University of Southern California San Diego.)
Skin Patch Measurements Closely Match Those of Traditional Devices
Test subjects wore the patch on their neck while performing various combinations of the following tasks:
exercising on a stationary bicycle,
eating a high-sugar meal,
drinking an alcoholic beverage, and
drinking a caffeinated beverage.
The results of the measurements taken from the patch closely matched measurements collected by traditional monitoring devices such as a:
For now, the patch must be connected to an external power source which transmits the reading to a counter-top machine, but the researchers hope to create a wireless version in the future.
“There are opportunities to monitor other biomarkers associated with various diseases,” Sempionatto said in the UCSD press release. “We are looking to add more clinical value to this device.”
Other Similar Skin Patch Monitoring Technologies
Though an important breakthrough, the UCSD’s device is not the first skin patch monitor to be developed.
Multiple research and clinical studies are underway that hope to prove the accuracy and safety of wearable devices at detecting and monitoring certain health conditions. It’s a worthy goal.
Skin patches, such as the one created at UCSD, could enable clinical laboratories to provide value-added service to medical professionals and patients alike. Medical labs could potentially monitor skin patch readings in real-time and notify physicians and patients of changes in biomarkers that require attention.
Further, as this technology is developed, it will likely find a ready market with the latest generation of consumers who are more willing than previous generations to buy their own diagnostic tests for home use. These “next-generation” healthcare consumers have demonstrated their willingness to use Apple watches, Fitbits, and similar wearable devices to monitor their condition during exercise and other health metrics.
Pathologists and clinical laboratory managers should not overlook the potential for robust consumer demand to accelerate development and market adoption of such skin patches.
