But a new study from the Cancer Therapy & Research Center at The University of Texas Health Science Center at San Antonio shows that some types of immunotherapy previously thought to work only in younger patients can be used to help the elderly, with less toxic effects than many common therapies, if combined in ways that account for age-related changes in the immune system.
"We've shown that immunotherapy for cancer not only works in aged mice, but actually can work better in aged hosts than in young counterparts by capitalizing on the immune changes that happen with age," said Tyler Curiel, M.D., MPH, a professor in the School of Medicine at the Health Science Center and principal investigator of the study, published April 15 in Cancer Research.
As you age, most parts of your body begin to wear out. They keep doing what they're made to do, Dr. Curiel said, but over time, they don't do it as well. The general perception is that the immune system also simply declines with age. "That's really too simplistic," he said. "That's really not the full picture of what's happening."
The body's immune system does weaken with age, but it also changes, and that changes the rules for fighting disease within the body. Dr. Curiel's group started by examining an immune therapy that they previously had shown to work in younger hosts, including cancer patients. It's designed to eliminate regulatory T cells (called Tregs), which are cells that turn off immune responses, allowing cancer to progress. Tregs increase in cancer. In young hosts, the drug turns off Treg activity, allowing the immune system to function better. In older hosts, even though the drug turns off the Tregs, it has no clinical benefit.
Dr. Curiel asked the question why, and in this paper his team explains the answer. In older mice, when the drug turned off the Tregs, the researchers found that another type of immune suppressor cell (a myeloid-derived suppressor cell or MDSC) exploded in number to take the Tregs' place, hampering clinical efficacy. That did not happen in young mice.
The team added a second drug that targets the MDSC, and found that with those tools to help immunity, the older hosts can combat cancer just as well as the younger hosts. Adding the second drug afforded no clinical benefit to young hosts, as their MDSC numbers had not increased.
"We've shown that an aged immune system can combat cancer just as well as a young one if you remove the impediments to successful immunity, which are different that those in younger hosts," Dr. Curiel said. "We've shown that if you test all your immune therapy just in young mice and young people, you'll never learn how it works in older patients — the ones most at risk for cancer. You might conclude that drugs don't work in aged hosts, when they do. But they have to be combined with some help."
After discovering this in melanoma, the researchers then looked at whether the same action held true in colon cancer, a major cancer killer in the elderly.
"The details were different in colon cancer. The bad immune cells that increased in the aged mice and how they were knocked down by the drugs were different than in melanoma," Dr. Curiel said. "But the result was the same — we identified a drug combination that was highly effective in the aged mice."
That means that not only must this strategy be developed with regard to the age of the patient, he said, it also must be specific to the cancer.
"It's a bit complicated, but it's possible to put into practice, and because these approaches could be so much more specific and so much better tolerated than conventional chemotherapy, it is well worth pursuing. We are grateful to the Voelcker Foundation and the Holly Beach Public Library Association for funding this work." he said.
The next step is to test these concepts in an immune therapy clinical trial for elderly patients, which the research team plans to do, Dr. Curiel said.
For current news from the UT Health Science Center, please visit our news release website or follow us on Twitter @uthscsa.
The Cancer Therapy & Research Center (CTRC) at The University of Texas Health Science Center at San Antonio is one of the elite academic cancer centers in the country to be named a National Cancer Institute (NCI) Designated Cancer Center, and is one of only four in Texas. A leader in developing new drugs to treat cancer, the CTRC Institute for Drug Development (IDD) conducts one of the largest oncology Phase I clinical drug programs in the world, and participates in development of cancer drugs approved by the U.S. Food & Drug Administration. For more information, visit www.ctrc.net.
Elizabeth Allen | EurekAlert!
Inselspital: Fewer CT scans needed after cerebral bleeding
20.03.2019 | Universitätsspital Bern
Building blocks for new medications: the University of Graz is seeking a technology partner
19.03.2019 | Karl-Franzens-Universität Graz
Cancers that display a specific combination of sugars, called T-antigen, are more likely to spread through the body and kill a patient. However, what regulates...
DESY and MPSD scientists create high-order harmonics from solids with controlled polarization states, taking advantage of both crystal symmetry and attosecond electronic dynamics. The newly demonstrated technique might find intriguing applications in petahertz electronics and for spectroscopic studies of novel quantum materials.
The nonlinear process of high-order harmonic generation (HHG) in gases is one of the cornerstones of attosecond science (an attosecond is a billionth of a...
Nano- and microtechnology are promising candidates not only for medical applications such as drug delivery but also for the creation of little robots or flexible integrated sensors. Scientists from the Max Planck Institute for Polymer Research (MPI-P) have created magnetic microparticles, with a newly developed method, that could pave the way for building micro-motors or guiding drugs in the human body to a target, like a tumor. The preparation of such structures as well as their remote-control can be regulated using magnetic fields and therefore can find application in an array of domains.
The magnetic properties of a material control how this material responds to the presence of a magnetic field. Iron oxide is the main component of rust but also...
Due to the special arrangement of its molecules, a new coating made of corn starch is able to repair small scratches by itself through heat: The cross-linking via ring-shaped molecules makes the material mobile, so that it compensates for the scratches and these disappear again.
Superficial micro-scratches on the car body or on other high-gloss surfaces are harmless, but annoying. Especially in the luxury segment such surfaces are...
The Potsdam Echelle Polarimetric and Spectroscopic Instrument (PEPSI) at the Large Binocular Telescope (LBT) in Arizona released its first image of the surface magnetic field of another star. In a paper in the European journal Astronomy & Astrophysics, the PEPSI team presents a Zeeman- Doppler-Image of the surface of the magnetically active star II Pegasi.
A special technique allows astronomers to resolve the surfaces of faraway stars. Those are otherwise only seen as point sources, even in the largest telescopes...
11.03.2019 | Event News
01.03.2019 | Event News
28.02.2019 | Event News
26.03.2019 | Physics and Astronomy
26.03.2019 | Physics and Astronomy
26.03.2019 | Physics and Astronomy