A study published in the Journal of Orthopaedic Research has identified a bone matrix protein called Secreted phosphoprotein 24 kD (Spp24) that may help to treat osteosarcoma, the most common type of bone cancer.
In experiments conducted in cells and mice, investigators found that Spp24 inhibits the proliferation and invasiveness of osteosarcoma tumour cells and promotes their apoptosis, or death. Mechanistically, Spp24 binds to and neutralises a protein called bone morphogenetic protein 2, which has tumour-enhancing properties.
“Spp24 and its proteolytic products have a number of effects on bone metabolism that have been elucidated to various degrees. They have the potential to be engineered into bone therapeutics, and this anti-tumour effect through bone morphogenetic protein 2 sequestration is only one such example,” said co–corresponding author Haijun Tian, MD, PhD, of Shanghai Jiao Tong University School of Medicine. “Like many other bone matrix proteins, the more we look into the function of Spp24, the more surprising roles we find even though the primary function of Spp24 remains uncertain.”
Hayley Arcenaux, seated furthest left, is the Medical Officer for the Inspiration4 flight. She is a survivor of childhood cancer and works as a physician assistant at St Jude’s Children’s Hospital, for which the flight is raising funds and awareness.
The first chartered spaceflight into orbit, scheduled for launch on September 15, will have a crewmember who is both a childhood cancer survivor and physician assistant as part of the crew.
The three-day long mission aboard a SpaceX Dragon spacecraft was chartered by entrepreneur Jared Isaacman. Dubbed Inspiration4, the flight is in fact also raising money and awareness for St Jude Children’s Hospital, which was given two of the four seats on the spacecraft. The funds raised for the hospital are believed to have exceeded the cost of the flight.
Isaacman offered the first seatto 29 year-old Hayley Arceneux, who works as a physician assistant at St Jude’s and will be the medical officer for the flight. She was also a patient at the very same hospital. At age 10, she was diagnosed with osteosarcoma, the most common primary paediatric bone malignancy. In addition to a dozen rounds of chemotherapy, she had a limb-sparing operation which replaced her knee and inserted a titanium reinforcing rod in her femur. This will make her the first person with a prosthetic in space. Such a medical history would have immediately disqualified her for astronaut selection with any of the government-run space agencies like NASA.
In an interview with The Cut, she described her work as a physician assistant at St Jude’s: “I work inpatient… with leukaemia and lymphoma patients specifically. The majority of them received their cancer diagnoses pretty recently, so a big part of my role is helping to educate and support families through the beginning of treatment. I help them understand, What is cancer? What does the treatment process look like? What should I expect?
“We also manage the kids while they are in treatment. If they get an infection or if they get a fever, we take that really seriously. So I’ll manage their IV antibiotics or other treatment-related complications that can occur.. I check on patients, assess labs, order tests, update families on the results, order meds for outpatients. It is a lot of coordinating and educating. It’s hard, but it’s the greatest job in the world.”
St Jude’s held an auction for the other crew seat that Isaacman offered. The winning bidder declined the seat and gifted it to data engineer Christopher Sembroski. The final seat was won in an entrepreneurial competition by Dr Sian Proctor, a geologist and pilot who narrowly missed out on being chosen as a NASA astronaut.
Speaking about the auction, Richard C. Shadyac Jr, president and chief executive of American Lebanese Syrian Associated Charities, which raised fund for St Jude’s, said: “The impact of the Inspiration4 mission has been immeasurable, serving as an incredible platform to educate and engage millions in the movement to find cures and deliver care for childhood cancer and other catastrophic diseases through accelerated research and treatment. The auction is a critical component of the overall campaign as it enables us to reach new audiences and supporters as we work to fulfill our mission.”
So far, $100 million has been raised for St Jude’s.
While in space, the crew will conduct experiments such as examining fluid shifts in zero gravity using ultrasound, as well as other medical experiments including measuring blood glucose levels — in order to help expand space travel to those with diabetes.
A documentary has been made of the crew’s training, and is available to stream on Netflix.
