
By GWEN MURANAKA, Rafu Senior Editor
Two remarkable individuals — one born atop a mountain in Mie Prefecture; the other flying into space aboard Inspiration4 — are united in common cause — to defeat pediatric cancer.
Dr. Hiroto Inaba and Hayley Arceneaux, a physician’s assistant, work together at St. Jude Children’s Research Hospital in Memphis. St. Jude was founded by entertainer Danny Thomas with the mission to advance cures for catastrophic pediatric diseases and treat children, regardless of race, religion or a family’s ability to pay.
Inaba is an oncologist at St. Jude and the principal investigator for the Total Therapy 17 clinical trial. He is also a 17th-generation descendant of Inaba Yoshimichi (稲葉 良通), a samurai warrior during Japan’s Sengoku Period, serving under the legendary daimyo Oda Nobunaga.
“I was born on the top of a mountain in an isolated area. I noticed that there were many cancer patients in my family. My mom died early,” Inaba explained of his decision to pursue a career in medicine.

He received an M.D. and Ph.D from Mie University School of Medicine, working in Japan as a pediatric cancer doctor for nine years before being accepted as a fellow at St. Jude.
“Initially wanted to help Japanese people. This institution is so phenomenal I decided that I cannot leave here and I have stayed for last the 18 years,” Inaba said.
“St. Jude is really shining as a number one facility of pediatric cancer and I really wanted to come here and so I started my residency.”
In 2011, Inaba was recognized with the Outstanding Physician Award at the hospital. He also does patient consultations in Asia. Speaking via Zoom, he says his samurai background instilled his determination to find a cure for pediatric cancer.
“Samurai used to fight a lot. My fight is against cancer,” he explained.
Inaba is the principal investigator for the Total Therapy 17 clinical trial, which investigates treatments for acute lymphoblastic leukemia (ALL) and lymphoma.
The objective of Total 17 is to further refine this selection process with precision medicine. Every child in the trial undergoes genomic testing of both normal tissue and leukemia cells to target the therapy. The leukemia-cell data can identify abnormal mutations that may be targetable by new drugs.

“Warriors must be flexible. For example, our technology, diagnosis, treatment keep changing. We are seeing a 94 percent survival rate with ALL, but we still want to go to 100 percent. There is a way to get there. We have many things to do. I’m foreseeing in the next 10 years very individualized therapies.”
Arceneaux’s journey to St. Jude started in a very different way. She was 10 years old growing up in St. Francisville, La., when she found a lump and was experiencing pain in her left leg. Doctors who examined Arceneaux revealed a devastating diagnosis: osteosarcoma, or bone cancer. Her dad did a search on the Internet and found St. Jude. Soon, the family was on their way to Memphis, where Arceneaux spent over a year in treatment, including about a dozen rounds of chemotherapy bracketed around surgery to remove her knee and part of her thigh bone, as well as the placement of a titanium rod in her left leg.
Her experience as a patient led Arceneaux to want to return to St. Jude as a career. She received her physician’s assistant degree from LSU Health in Shreveport, La. in 2016, and is part of a team treating leukemia and lymphoma patients at St. Jude. Among the doctors, Arceneaux works with is Dr. Inaba.
“I get my list of patients, labs, vitals, results. We examine the patients and do rounds, with Dr. Inaba. It’s a whole team coming together to come up with a plan of the day, order tests, discuss the results with the families,” Arceneaux said.
She beamed as she talked about Dr. Inaba.
“He’s so empowering, so kind, so good with the kids. Bring them all little gifts when he sees them,” she said. “A patient brought him a really bright tie, and he immediately put it on. He’s incredible with the kids.”
Arceneaux had to leave her work temporarily for a new, critical mission: to train to join the crew of Inspiration4.

Dr. Inaba recalled the last day before Arceneaux left the hospital before the launch into space on Sept. 16 from Kennedy Space Center in Cape Canaveral. Inspiration4 was SpaceX’s first private spaceflight.
“She started crying. I asked, ‘Why are you crying?’ She said, ‘I’m excited to go into space but I’m sad to leave St. Jude even for a little while.’”
When candidates were sought for the Inspiration4 flight, Arceneaux was selected to represent the hope of cancer patients and was assigned to be the crew’s chief medical officer. At 29, she is the youngest person to fly into space and also the first with a prosethesis.
The Inspiration4 crew, which included from Shift4 Payment Chief Executive Officer and Mission Commander Jared Isaacman, Dr. Sian Proctor and Chris Sembroski, trained at the SpaceX facility in the Dragon capsule simulator in Hawthorne.
While in orbit, the crew collected data to help understand the effects of space on the human body and chatted in a live video call with St. Jude patients. To date, Inspiration4 has secured commitments of more than $240 million for St. Jude. In November, St. Jude named its new $412 million research facility the Inspiration4 Advanced Research Center in honor of space flight.

Arceneaux said one of the most difficult aspects of training was climbing Mt. Rainier in Washington, something she never thought she could accomplish with her internal prosthesis.
“I thought about my patients on the mountain. Climbing is a lot like cancer treatment, it’s one step at a time. The whole mission was for them. They all want to be astronauts now!”
In the zero-gravity environment of space, Arceneaux said there was no pain in her leg and the view of Earth was inspiring. Among the people invited to attend the launch was the orthopedic surgeon who treated her when she was a kid. She is scheduled to go back to her work as a physician’s assistant next month and wants to continue to travel the world, including Asia.
Both Inaba and Arceneaux said the main message they want to give their patients is simple — it’s to have hope.
“I love these kids with my whole heart,” Areceneaux said. “Getting to support them and help these kids get better, greatest honor of my life.”
Inaba reflected that Arcenaux’s journey from cancer patient to astronaut is an example of what is possible.
“I never explain the disease without hope, hope of a cure, hope of a good life,” he said. “Whatever the situation is, we’re going to help fight the disease. They are the fighters, we are the supporters.”