Targeting microRNAs could unmask hidden vulnerability in breast cancer stem cells
2021-04-02
(Press-News.org) Researchers in Italy have identified a pair of microRNA molecules that help maintain a population of cancerous stem cells that drive the growth of breast cancers and initiate tumor relapse after treatment. The study, which will be published April 2 in the Journal of Cell Biology (JCB), reveals that targeting these microRNAs makes cancer stem cells more susceptible to some chemotherapies and could potentially improve the prognosis of patients with aggressive forms of breast cancer.
Many tumors contain a small population of cancer stem cells that initiate tumor growth and give rise to the various cell types found in tumors. Moreover, because cancer stem cells are often resistant to radio- and chemotherapies, they can survive and promote tumor relapse and metastasis after initial rounds of treatment. In breast cancer, for example, tumors containing a relatively high number of cancer stem cells have a much poorer prognosis than tumors with fewer stem cells.
Eliminating these stem cells may therefore be crucial for the successful treatment of breast cancer and other tumor types. One class of molecule that might help cancer stem cells to persist within tumors is microRNAs. These short RNA molecules control the fate and identity of cells by regulating the levels of hundreds of longer, protein-encoding "messenger" RNAs.
"We wanted to identify microRNAs required for the maintenance of normal mammary stem cells that are inherited by cancer stem cells and could represent potential therapeutic targets in breast cancer," says Francesco Nicassio, a principal investigator and Center Coordinator of the Center for Genomic Science at the Italian Institute of Technology in Milan.
In the new study, Nicassio and colleagues, including co-senior author Pier Paolo Di Fiore, a group leader at the European Institute of Oncology and professor at the University of Milan, identified two closely related microRNAs, miR-146a and miR-146b, that are present in breast cancer stem cells as well as normal mammary stem cells. Indeed, the levels of these two microRNAs tended to be highly elevated in aggressive breast cancers that have a high number of cancer stem cells and a poor prognosis.
The researchers found that miR-146a/b are required to maintain the pool of cancer stem cells. Depleting these two microRNAs from patient-derived cancer cells reduced the ability of these cells to form new tumors when implanted into mice.
Nicassio and colleagues determined that miR-146a/b regulate hundreds of messenger RNAs, thereby controlling numerous cellular processes such as metabolism and DNA replication. Depleting miR-146a/b from cancer stem cells might alter these processes in ways that leave the cells more vulnerable to chemotherapy. Nicassio and colleagues found that reducing the levels of miR-146a/b made breast cancer stem cells over 20 times more sensitive to methotrexate, significantly improving this metabolic inhibitor's ability to restrict tumor growth in mice.
"While the molecular details remain to be determined, our results clearly show that reducing miR-146a/b levels represents an attractive approach to overcome some forms of drug resistance in the clinical setting, unmasking a 'hidden vulnerability' exploitable for the development of anti-cancer stem cell therapies," Nicassio says.
INFORMATION:
Tordonato et al., 2021. J. Cell Biol.
https://rupress.org/jcb/article-lookup/doi/10.1083/jcb.202009053?PR
About Journal of Cell Biology Journal of Cell Biology (JCB) publishes peer-reviewed research in any area of basic cell biology as well as applied cellular advances in fields such as immunology, neurobiology, metabolism, microbiology, developmental biology, and plant biology. All editorial decisions on research manuscripts are made through collaborative consultation between professional editors with scientific training and academic editors who are active in the field. Established in 1955, JCB is published by Rockefeller University Press, a department of The Rockefeller University in New York. For more information, visit jcb.org.
Visit our Newsroom, and sign up for a weekly preview of articles to be published. Embargoed media alerts are for journalists only.
Follow JCB on Twitter at @JCellBiol and @RockUPress.
[Attachments] See images for this press release:
ELSE PRESS RELEASES FROM THIS DATE:
2021-04-02
Researchers at the University of California, San Francisco, have discovered that aggressive, triple-negative breast cancers (TNBCs) can evade treatment by reorganizing and softening the collagen matrix that surrounds the cancer cells. The study, which will be published April 2 in the Journal of Experimental Medicine (JEM), shows that the softer matrix activates a signaling pathway that promotes the cancer cells' survival, and suggests that targeting this pathway could enhance the effectiveness of chemo- and radiotherapy in TNBC patients.
TNBC is an aggressive type of breast cancer with worse survival rates than other forms of the disease. Because TNBC cells lack the HER2 signaling ...
2021-04-02
A team of researchers has identified several candidates for drugs against the coronavirus SARS-CoV-2 at DESY´s high-brilliance X-ray lightsource PETRA III. They bind to an important protein of the virus and could thus be the basis for a drug against Covid-19. In a so-called X-ray screening, the researchers, under the leadership of DESY, tested almost 6000 known active substances that already exist for the treatment of other diseases in a short amount of time. After measuring about 7000 samples, the team was able to identify a total of 37 substances that bind to the main protease (Mpro) of the SARS-CoV-2 virus, as the scientists report online today in the journal ...
2021-04-02
Glassy materials play an integral role in the modern world, but inherent brittleness has long been the Achilles' heel that severely limits their usefulness. Due to the disordered amorphous structure of glassy materials, many mysteries remain. These include the fracture mechanisms of traditional glasses, such as silicate glasses, as well as the origin of the intriguing patterned fracture morphologies of metallic glasses.
Cavitation has been widely assumed to be the underlying mechanism governing the fracture of metallic glasses, as well as other glassy systems. Up until now, however, scientists ...
2021-04-02
A new study indicates holes the solution to operational speed/coherence trade-off, potential scaling up of qubits to a mini-quantum computer.
Quantum computers are predicted to be much more powerful and functional than today's 'classical' computers.
One way to make a quantum bit is to use the 'spin' of an electron, which can point either up or down. To make quantum computers as fast and power-efficient as possible we would like to operate them using only electric fields, which are applied using ordinary electrodes.
Although spin does not ordinarily 'talk' to electric fields, in some materials spins can interact with electric fields indirectly, and these are some of the hottest materials currently studied ...
2021-04-02
In May 2020, a team led by thoracic surgeon Konrad Hoetzenecker of the Department of Surgery of MedUni Vienna and Vienna General Hospital performed a lung transplant on a 44-year-old patient who had been seriously ill with Covid-19, making her the first patient in Europe to receive a lung transplant for this indication. The Vienna lung transplantation programme now plays a leading role in an international consortium comprising experts from the USA, Europe and Asia. Based on the expertise from Vienna, approximately 40 transplants have now been carried out on Covid-19 patients throughout the world. In a study published in the leading journal ...
2021-04-02
Russian researchers have developed an inexpensive, safe, and reliable packed eggs surface disinfection technology. This technology helps to kill bacteria, including salmonella, on eggshells. Also, it allows growing broiler chickens with strong immunity to viral diseases. Packed eggs are disinfected with 50 nanoseconds (one billionth of a second) electron beam. Disinfection takes place in plastic containers. The description of the technology was published in Food and Bioproducts Processing.
"Disinfection of the packed eggs protects eggs from subsequent contamination during storage", said Sergey Sokovnin, a professor at Ural Federal University and Ural Branch of Russian Academy of Science. "We found out that 5 kGy is enough for disinfection. Such dose allows to ...
2021-04-02
Niigata, Japan - Cancer is the world's second deadliest disease which contributes towards the fatality of over 10 million people per year. Oncologists adopt a variety of treatment procedures to treat cancer cells. Among the different methods used to fight cancer, chemotherapeutic treatment is a prominent and well-adopted technique. It is a drug based method, wherein powerful chemical compounds are injected into the body to annihilate the malignant cells. Although these chemicals support the destruction of the cancerous cells, optimizing their dosage has always been a challenge to the medical ...
2021-04-02
In United Nations Sustainable Development Goals, Number 6, addresses the need for access to clean water and sanitation for all. In the worldwide situation, one in three people do not have access to safe drinking water, and two out of five do not have basic hand-washing facilities with soap and water.
Water quality also address to elements dissolved. In the case of fluoride, controlled amount are recommended for protect tooth, e.g. included in toothpaste. Higher levels can cause fluorosis, interfere in tooth enamel formation, correct growth of the bones, and cause crippling deformities of the spine and joints. The incidence of higher concentrations of fluoride in water is higher in rural areas without ...
2021-04-02
Eczema, or atopic dermatitis (AD), is sometimes called "the itch that rashes." Often, the itch begins before the rash appears, and, in many cases, the itchiness of the skin condition never really goes away. Approximately 9.6 million children and 16.5 million adults in the U.S. have AD, which can have a serious effect on quality of life for patients. Although much has been learned about the uncomfortable sensation that triggers the desire to scratch, many mysteries remain about chronic itch, making it a challenge to treat. A paper by authors from Brigham and Women's Hospital and Harvard Medical School published in The Proceedings ...
2021-04-02
The interfacial decomposition products forming the so-called solid-electrolyte interphase (SEI) during the first charging/discharging significantly determine the electrochemical performances of lithium (Li) batteries. To date, the dynamic evolutions, chemical compositions, stabilities and the influencing factors of the SEI films have been captured tremendous attentions.
It's noted that, in contrast to the SEI film formation at the surface of electrodes, a kind of SEI shells usually conformally forms at the outmost layer of the on-site deposited Li once the freshly deposited Li contacts with the electrolyte, which could directly influence Li nucleation, growth behaviors ...
LAST 30 PRESS RELEASES:
[Press-News.org] Targeting microRNAs could unmask hidden vulnerability in breast cancer stem cells