PRESS-NEWS.org - Press Release Distribution
PRESS RELEASES DISTRIBUTION

Nanospheres shield chemo drugs, safely release high doses in response to tumor secretions

2015-07-14
(Press-News.org) Scientists have designed nanoparticles that release drugs in the presence of a class of proteins that enable cancers to metastasize. That is, they have engineered a drug delivery system so that the very enzymes that make cancers dangerous could instead guide their destruction.

"We can start with a small molecule and build that into a nanoscale carrier that can seek out a tumor and deliver a payload of drug," said Cassandra Callmann, a graduate student in chemistry and biochemistry at the University of California, San Diego, and first author of the report published in the journal Advanced Materials July 14.

The system takes advantage of a class enzymes called matrix metalloproteinases that many cancers make in abundance. MMPs chew through membranes, allowing cancer cells to escape to colonize other regions of the body, often with deadly consequences.

Callmann created tiny spheres packed with the anti-cancer drug paclitaxel (also known by the trade names Taxol and Onxal) and coated with a peptide shell. MMPs tear up that shell, releasing the drug. The shell fragments form a ragged mesh that holds the drug molecules near the tumor.

The work, led by Nathan Gianneschi a professor of chemistry and biochemisty at UC San Diego, builds on his group's earlier sucess using a similar strategy to mark tumors for both diagnosis and precise surgical removal.

To package the drug into the spheres, Callmann had to add chemical handles. As it turns out, a group of atoms essential to the drug molecule's effectiveness, and also toxicity, made for a good attachment point. That means the drug was inactivated as it flowed through the circulatory system until it reached the tumor.

The protection allowed the researchers to safely give a dose 16 times higher than they could with the formulation now used in cancer clinics, in a test in mice with grafted in fibrosarcoma tumors.

In additional preliminary tests, Callmann and colleagues were able to halt the growth of the tumors for a least two weeks, using a single lower dose of the drug. In mice treated with the nanoparticles coated with peptides that are impervious to MMPs or given saline, the tumors grew to lethal sizes within that time.

Gianneschi says they will broaden their approach to create delivery systems for other diagnostic and therapeutic molecules. "This kind of platform is not specific to paclitaxel. We'll test this in other models - with other classes of drug and in mice with a cancer that mimics metastatic breast cancer, for example."

They'll also continue to modify the shell, to provide even greater protection and avoid uptake by organs such as liver, spleen and kidneys, he said. "We want to open up this therapeutic window."

INFORMATION:

Additional authors include Matthew Thompson in Gianneschi's chemistry research group and Christopher Barback, David Hall and Robert Mattrey in UC San Diego's Moores Cancer Center. All animal procedures were approved by UC San Diego's institution animal care and use committee. Callmann holds a fellowship through the Cancer Researchers in Nanotechnology Program at UC San Diego. The National Institute of Biomedical Imaging and Bioengineering provided financial support.

This novel approach to using enzyme-directed assembly of particle theranostics (EDAPT) is patent pending. Skip Cynar, scynar@ucsd.edu , in UC San Diego's technology transfer office can provide information about commercial development.



ELSE PRESS RELEASES FROM THIS DATE:

Closing the quality chasm in mental health and substance use care

2015-07-14
NEW YORK, NY (July 14, 2015) - A plan to ensure that evidence-based psychosocial interventions are routinely used in clinical practice and made a part of clinical training for mental health professionals was released today by the National Academy of Medicine (NAM). The NAM report, titled, "Psychosocial Interventions for Mental and Substance Use Disorders," points to a strong need to strengthen evidence on the effectiveness of psychosocial interventions, and to develop guidelines and quality measures for implementing these interventions in professional practice. Though ...

High-pressure oxygen can effectively treat fibromyalgia

2015-07-14
Fibromyalgia is almost impossible to diagnose. The chronic pain syndrome strikes an estimated 1 in 70 Americans, most of them women. The disorder is often triggered by head trauma, a neurological infection, or severe emotional stress, and is characterized by symptoms such as musculoskeletal pain, fatigue, memory loss and mood swings. Fibromyalgia is often mistaken for other culprits and most patients suffer months, even years, of unrelenting pain before being properly diagnosed. And once diagnosed, patients enjoy little respite because few therapies have been found to be ...

Key protein controls nutrient availability in mammals

2015-07-14
Case Western Reserve researchers already demonstrated that a single protein plays a pivotal role in the use of nutrients by major organs that allow for the burning of fat during exercise or regulating the heart's contractile and electrical activity. Now they have found a new benefit of Kruppel-like Factor 15 (KLF15) -- keeping the body in metabolic balance. The discovery, which highlights how KLF15 affects the availability of nutrients in the body, may also have significant implications for scientists' ability to understand ways that the body metabolizes different medications. ...

Obesity-related behaviors increase when school's out

2015-07-14
July 13, 2015 --Regardless of family income, children on summer break consume more sugar, watch more television, and eat fewer vegetables than the rest of the year, according to researchers at Columbia University's Mailman School of Public Health. Findings are published online in the Journal of School Health. The research was based on data from U.S. children in grades 1-12 in the National Health and Nutrition Examination Survey 2003-2008. The sample consisted of 6453 children and adolescents, some surveyed during the school year and others during a school break. The ...

Traditional Chinese exercises may help patients with COPD

2015-07-14
Liuzijue qigong (LQG) is a set of meditative movement and breathing patterns practiced by more than 100 million people in China. In a new Journal of the American Geriatrics Society study, chronic obstructive pulmonary disease (COPD) patients in remission who were randomized to LQG demonstrated marked improvements in their lung function, general health, mental health, and quality of life after 6 months compared with patients randomized to a control group. The LQG program consisted of four 45-minute sessions each week and daily walking for 30 minutes. Control participants ...

Framework to establish standards for psychosocial interventions used to treat mental health and subs

2015-07-14
WASHINGTON - A considerable gap exists in mental health and substance abuse treatments known as psychosocial interventions between what is known to be effective and those interventions that are commonly delivered, says a new report from the National Academies of Sciences, Engineering, and Medicine. Mental health and substance use disorders are a serious public health problem, affect approximately 20 percent of the U.S. population, and often occur together. Psychosocial interventions -- such as psychotherapies, community-based treatments, vocational rehabilitation, ...

Am I fat? Many of today's adolescents don't think so

2015-07-14
Ann Arbor, MI, July 14, 2015 - Admitting that you have a weight problem may be the first step in taking action, but a new study published in the American Journal of Preventive Medicine found that an increasing number of overweight adolescents do not consider themselves as such. "Adolescents with accurate self-perceptions of their body weight have greater readiness to make weight-related behavioral changes and are more effective in making the changes," explained lead investigator Jian Zhang, MD, DrPH, from the Jiann-Ping Hsu College of Public Health, Georgia Southern University, ...

Oregon study suggests organic farming needs direction to be sustainable

Oregon study suggests organic farming needs direction to be sustainable
2015-07-14
EUGENE, Ore. -- Large-scale organic farming operations, based on a review of almost a decade of data from 49 states, are not reducing greenhouse gas emissions, says a University of Oregon researcher. The increasing numbers of commercialized organic operations -- which still make up just 3 percent of total agricultural lands -- appear to contribute to increased and more intense levels of greenhouse gases coming from each acre of farmland, reports Julius McGee, a doctoral student in the UO sociology department. His study appeared in the June issue of the journal Agriculture ...

Physician peer influence affects repeat prescriptions: INFORMS Marketing Science

2015-07-14
A new study published in Marketing Science, a journal of the Institute for Operations Research and the Management Sciences (INFORMS), finds that peer influence among physicians can affect both trial and repeat prescription behavior of a risky new prescription drug. The study, Social Contagion in New Product Trial and Repeat, tracks prescriptions of a new drug over 17 months, and measures the discussion and patient referral connections among physicians in New York, Los Angeles, and San Francisco. The research was conducted by professors Raghuram Iyengar and Christophe ...

Memory-loss man case 'like nothing we have ever seen before'

2015-07-14
University of Leicester psychologist describes unique case as new to science 38-year-old fit and healthy man suffered memory loss after local anaesthetic and root-canal treatment at dentist For the past decade he can only remember up to 90 minutes And he awakes each day thinking it is the same day he went to the dentist Symptoms are akin to those depicted in movies such as Groundhog Day and Memento There is no evidence that the treatment at the dentist can be blamed for his condition "One of our reasons for writing up this individual's case was that we ...

LAST 30 PRESS RELEASES:

Scientists trace origins of now extinct plant population from volcanically active Nishinoshima

AI algorithm based on routine mammogram + age can predict women’s major cardiovascular disease risk

New hurdle seen to prostate screening: primary-care docs

MSU researchers explore how virtual sports aid mental health

Working together, cells extend their senses

Cheese fungi help unlock secrets of evolution

Researchers find brain region that fuels compulsive drinking

Mental health effects of exposure to firearm violence persist long after direct exposure

Research identifies immune response that controls Oropouche infection and prevents neurological damage

University of Cincinnati, Kent State University awarded $3M by NSF to share research resources

Ancient DNA reveals deeply complex Mastodon family and repeated migrations driven by climate change

Measuring the quantum W state

Researchers find a way to use antibodies to direct T cells to kill Cytomegalovirus-infected cells

Engineers create mini microscope for real-time brain imaging

Funding for training and research in biological complexity

The Journal of Nuclear Medicine Ahead-of-Print Tip Sheet: September 12, 2025

ISSCR statement on the scientific and therapeutic value of human fetal tissue research

Novel PET tracer detects synaptic changes in spinal cord and brain after spinal cord injury

Wiley advances Knowitall Solutions with new trendfinder application for user-friendly chemometric analysis and additional enhancements to analytical workflows

Benchmark study tracks trends in dog behavior

OpenAI, DeepSeek, and Google vary widely in identifying hate speech

Research spotlight: Study identifies a surprising new treatment target for chronic limb threatening ischemia

Childhood loneliness and cognitive decline and dementia risk in middle-aged and older adults

Parental diseases of despair and suicidal events in their children

Acupuncture for chronic low back pain in older adults

Acupuncture treatment improves disabling effects of chronic low back pain in older adults

How interstellar objects similar to 3I/ATLAS could jump-start planet formation around infant stars

Rented e-bicycles more dangerous than e-scooters in cities

Ditches as waterways: Managing ‘ditch-scapes’ to strengthen communities and the environment

In-situ molecular passivation enables pure-blue perovskite LEDs via vacuum thermal evaporation

[Press-News.org] Nanospheres shield chemo drugs, safely release high doses in response to tumor secretions