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UM Today the Magazine | Outsmarting a Brain Tumour – UM Today

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The little girl with the pink glasses and blue sweatshirt smiles back from a photo on the wall. It’s hung in Tamra Werbowetski-Ogilvie’s sixth-floor office, overlooking the treetops of the neighbourhood surrounding UM’s Bannatyne campus.

Alongside the framed photo are images of her own two children, including her daughter. She’s around the same age as this tween who was undergoing cancer treatment and who was connected to a foundation that funded Werbowetski-Ogilvie’s work in pediatric brain tumours—the deadliest of childhood cancers.

The Rady Faculty of Health Sciences researcher recalls chatting with the inquisitive girl on a Zoom call a year ago.

“Those are emotional meetings, you know? And I can’t get through them without crying. She was so thankful when I met her and just so happy that people were doing work,” says Werbowetski-Ogilvie. “It hits you. See? Already, I’m getting emotional.”

That’s why she opted for life as a stem cell biologist instead of a physician. Pediatric brain cancer became an obvious choice; it’s a discipline starving for discovery. This cancer is surprisingly rare in kids; it’s only been in the last decade that research in this specialized field has gained momentum, with advances in gene sequencing technology. But still, children’s cancers in general are “ridiculously underfunded,” Werbowetski-Ogilvie is quick to point out. “In the States, they account for less than four per cent of all funded research in cancer. And it’s the same everywhere.”

Roughly 1,000 kids are diagnosed with cancer in Canada every year, including about 50 in Manitoba. Around 10 of these children will learn they have a malignant tumour in their still-developing brain. A few of them will be diagnosed with a medulloblastoma tumour—the type Werbowetski-Ogilvie investigates.

“Parents don’t care how rare it is. They want to look for better treatments.”

She’s saying this just weeks before the prestigious journal Nature publishes what is possibly her team’s biggest findings to date. With collaborators in Toronto, Seattle and Tokyo, they pinpointed how and where aggressive types of medulloblastoma first appear—in pre-malignant form—during a child’s brain development, while still in the womb. Kids aren’t usually diagnosed with this type of tumour, known as group 4, until age seven, which suggests there’s a window of several years to prevent the cancer from ever happening.

Until now, group 4 tumours were the least understood, yet they require some of the most intense treatment. Up to 40 per cent of kids don’t survive.


Parents don’t care how rare it is. They want to look for better treatments.

With new clarity of which genes go awry and grow into tumours, clinicians could potentially detect these problematic cells before they turn into cancer—it’s the first time scientists have suggested medulloblastoma is preventable. They can also now develop better human cell models to test potential drugs to slow or stop its spread.

“With better models, we’ll actually be able to make some headway,” says Werbowetski-Ogilvie.

Brain cancer, she reiterates, doesn’t always get its moment in the spotlight. Greater attention tends to go toward unravelling the mysteries of leukemia, which affects the blood and is the most common cancer among children.

“In the leukemias it seems that there’s been better strides made in terms of survival rates. Whereas with brain tumours—especially for these really, really bad cases—current therapies are really not extending life beyond an extra couple of months and are so toxic,” she says. “We need to do better for brain tumours. And I think we are definitely moving in that direction.”

The search for new treatments finds fuel in cancer stem cell biology, where scientists identify a tumour’s “cellular fingerprint.”

“We’re looking for the proteins on the surface of a cell as well as inside the cell that make those tumours unique,” says Werbowetski-Ogilvie. “And then we look for drugs that will target that unique signature.” That way oncologists can go after diseased cells while leaving surrounding healthy cells intact.

This shift in approach will redefine the future of cancer care by offering alternatives to radiation and chemotherapy, which simply goes after all dividing cells, healthy or not, she explains. A more tailored approach is especially overdue for kids since they suffer worse long-term side effects from conventional options.

“Trials and drugs for children cannot be lumped into what is given to adults. They’re not the same. Everything we know about childhood cancer is different: the mutations, the drugs they’ll respond to, how they will respond. We’re dealing with developing bodies, right? And so we have to think about how we treat these diseases in very different ways.”

“This is where I’m meant to be,” says Tamra Werbowetski-Ogilvie, who held a Canada Research Chair in neuro-oncology and human stem cells for a decade.

She and her mostly female team—many of whom are mothers of young children—have spent years investigating another type of medulloblastoma—the sonic hedgehog brain tumour—which originates in the cerebellum. It was a postdoctoral fellow at Harvard Medical School, Robert Riddle, who first identified the protein behind the tumour’s growth. The protein belongs to the hedgehog genes. (Riddle raised eyebrows when he named it “sonic hedgehog” after the 1990s Sega videogame character.)

Werbowetski-Ogilvie set out to uncover a drug that would target this cancer and, in 2018, found that selumetinib slowed the tumour’s growth, as their hypothesis had hoped. But stopping the study there, Werbowetski-Ogilvie notes, would have been like plucking a dandelion from the surface rather than removing its root. So they pursued the possibility of a second drug—and serendipity stepped in.

Had COVID-19 closures in 2020 not shut down her lab, these experiments wouldn’t have been cut short, and her team wouldn’t have gathered data at the precise point that alerted them to just how fast not one, but a combination of drugs—selumetinib, along with pacritinib—was shrinking these tumours. “One model showed an almost 90 per cent reduction in the tumour’s growth. Over time, this translated to a greater than 40 per cent increase in survival,” she says. “You can just feel the excitement in the lab when a story is coming together and it’s all sort of clicking.”

Postdoctoral student Jamie Zagozewski [BSc(Hons)/09, MSc/12] remembers that moment well. “We were just blown away when we saw how much we could shrink the overall size of these tumours,” says Zagozewski, 37. “These parents are going through what I imagine is the worst thing in their entire life, and if I can have something to do with helping to ease that, that’s just incredible.”

Up until then, neither of these drugs had been tried on medulloblastoma—but since they have been used on other childhood cancers, approvals can come quicker, says Werbowetski-Ogilvie.

“I don’t like hearing the term, ‘It’s good enough,’” she says. “You have to stick with it and you have to keep putting in effort. Maximum effort.”

Biochemistry and medical genetics Prof. Tamra Werbowetski-Ogilvie grew up in Thunder Bay, Ont., changing diapers for her mom’s home daycare, and enjoying being around kids and their curiosity. Her dad, a petrographic technician who worked on asphalt and was known as “the rock doc,” would help her with her science projects with a go-to topic of—what else?—erosion. From there, she developed a passion for problem solving.

Finding new ways to treat brain cancer is especially complex since drug candidates must effectively reach tumours in this delicate organ. Many drugs are designed to not affect the brain, to not cross our blood-brain barrier, which protects toxins from getting in. Finding new, tailored treatments is made even more complicated since there are so many different types of tumours: 120 to be exact, according to the Brain Tumour Foundation of Canada.

Thankfully, in recent years, more affordable sequencing technology and an effort by the international research community to catalogue genetic differences among these tumours means scientists have a breakdown of genes involved in all forms of medulloblastoma. While this is extremely helpful, the data doesn’t speak to the behaviour of those genes and how they affect individual cells. It can be overwhelming to try to figure out which to narrow in on, admits Werbowetski-Ogilvie.

“When we get these large data sets, it’s our job to figure out which of these genes or proteins end up being functionally relevant. Not everything is,” she says. “It takes years to prioritize what to work on and figure out what our genes of interest actually do.”

In Werbowetski-Ogilvie’s office, on her whiteboard, are old doodles by her son that have been there so long they won’t erase. On her shelf is an anatomical model of a brain, and a ‘science lab’ her daughter made out of a milk cartoon, along with a drawing she did depicting Mom as Wonder Woman—something her team placed prominently during a surprise makeover of the space.

“What I teach in my lab, and what I teach my kids, is perseverance,” she says. “With science, sometimes experiments don’t work, but you have to stick with it.”

That’s not lost on Zagozewski, who says it’s no small thing to be part of a predominantly female team in a STEM field, led by a researcher who’s both tenacious and nurturing. “Not only are we scientists but we’re friends and mothers, all supporting each other,” she says. “It’s not just a job—it’s more than that.”

DID YOU KNOW? Pediatric oncologist Dr. Norma Ramsay [MD/68], a 2021 recipient of a UM Distinguished Alumni Award and mentor to dozens of female researchers, also found her calling in the emotionally charged field of childhood cancer. A leader in stem cell biology, she headed the acclaimed Pediatric and Blood Marrow Transplant Program at the University of Minnesota, improving mortality rates. And if treatments failed, she’d often drive to hospitals, no matter the time of day, to be with children in their last moments.

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Health Canada approves updated Moderna COVID-19 vaccine

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TORONTO – Health Canada has authorized Moderna’s updated COVID-19 vaccine that protects against currently circulating variants of the virus.

The mRNA vaccine, called Spikevax, has been reformulated to target the KP.2 subvariant of Omicron.

It will replace the previous version of the vaccine that was released a year ago, which targeted the XBB.1.5 subvariant of Omicron.

Health Canada recently asked provinces and territories to get rid of their older COVID-19 vaccines to ensure the most current vaccine will be used during this fall’s respiratory virus season.

Health Canada is also reviewing two other updated COVID-19 vaccines but has not yet authorized them.

They are Pfizer’s Comirnaty, which is also an mRNA vaccine, as well as Novavax’s protein-based vaccine.

This report by The Canadian Press was first published Sept. 17, 2024.

Canadian Press health coverage receives support through a partnership with the Canadian Medical Association. CP is solely responsible for this content.

The Canadian Press. All rights reserved.

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These people say they got listeria after drinking recalled plant-based milks

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TORONTO – Sanniah Jabeen holds a sonogram of the unborn baby she lost after contracting listeria last December. Beneath, it says “love at first sight.”

Jabeen says she believes she and her baby were poisoned by a listeria outbreak linked to some plant-based milks and wants answers. An investigation continues into the recall declared July 8 of several Silk and Great Value plant-based beverages.

“I don’t even have the words. I’m still processing that,” Jabeen says of her loss. She was 18 weeks pregnant when she went into preterm labour.

The first infection linked to the recall was traced back to August 2023. One year later on Aug. 12, 2024, the Public Health Agency of Canada said three people had died and 20 were infected.

The number of cases is likely much higher, says Lawrence Goodridge, Canada Research Chair in foodborne pathogen dynamics at the University of Guelph: “For every person known, generally speaking, there’s typically 20 to 25 or maybe 30 people that are unknown.”

The case count has remained unchanged over the last month, but the Public Health Agency of Canada says it won’t declare the outbreak over until early October because of listeria’s 70-day incubation period and the reporting delays that accompany it.

Danone Canada’s head of communications said in an email Wednesday that the company is still investigating the “root cause” of the outbreak, which has been linked to a production line at a Pickering, Ont., packaging facility.

Pregnant people, adults over 60, and those with weakened immune systems are most at risk of becoming sick with severe listeriosis. If the infection spreads to an unborn baby, Health Canada says it can cause miscarriage, stillbirth, premature birth or life-threatening illness in a newborn.

The Canadian Press spoke to 10 people, from the parents of a toddler to an 89-year-old senior, who say they became sick with listeria after drinking from cartons of plant-based milk stamped with the recalled product code. Here’s a look at some of their experiences.

Sanniah Jabeen, 32, Toronto

Jabeen says she regularly drank Silk oat and almond milk in smoothies while pregnant, and began vomiting seven times a day and shivering at night in December 2023. She had “the worst headache of (her) life” when she went to the emergency room on Dec. 15.

“I just wasn’t functioning like a normal human being,” Jabeen says.

Told she was dehydrated, Jabeen was given fluids and a blood test and sent home. Four days later, she returned to hospital.

“They told me that since you’re 18 weeks, there’s nothing you can do to save your baby,” says Jabeen, who moved to Toronto from Pakistan five years ago.

Jabeen later learned she had listeriosis and an autopsy revealed her baby was infected, too.

“It broke my heart to read that report because I was just imagining my baby drinking poisoned amniotic fluid inside of me. The womb is a place where your baby is supposed to be the safest,” Jabeen said.

Jabeen’s case is likely not included in PHAC’s count. Jabeen says she was called by Health Canada and asked what dairy and fresh produce she ate – foods more commonly associated with listeria – but not asked about plant-based beverages.

She’s pregnant again, and is due in several months. At first, she was scared to eat, not knowing what caused the infection during her last pregnancy.

“Ever since I learned about the almond, oat milk situation, I’ve been feeling a bit better knowing that it wasn’t something that I did. It was something else that caused it. It wasn’t my fault,” Jabeen said.

She’s since joined a proposed class action lawsuit launched by LPC Avocates against the manufacturers and sellers of Silk and Great Value plant-based beverages. The lawsuit has not yet been certified by a judge.

Natalie Grant and her seven year-old daughter, Bowmanville, Ont.

Natalie Grant says she was in a hospital waiting room when she saw a television news report about the recall. She wondered if the dark chocolate almond milk her daughter drank daily was contaminated.

She had brought the girl to hospital because she was vomiting every half hour, constantly on the toilet with diarrhea, and had severe pain in her abdomen.

“I’m definitely thinking that this is a pretty solid chance that she’s got listeria at this point because I knew she had all the symptoms,” Grant says of seeing the news report.

Once her daughter could hold fluids, they went home and Grant cross-checked the recalled product code – 7825 – with the one on her carton. They matched.

“I called the emerg and I said I’m pretty confident she’s been exposed,” Grant said. She was told to return to the hospital if her daughter’s symptoms worsened. An hour and a half later, her fever spiked, the vomiting returned, her face flushed and her energy plummeted.

Grant says they were sent to a hospital in Ajax, Ont. and stayed two weeks while her daughter received antibiotics four times a day until she was discharged July 23.

“Knowing that my little one was just so affected and how it affected us as a family alone, there’s a bitterness left behind,” Grant said. She’s also joined the proposed class action.

Thelma Feldman, 89, Toronto

Thelma Feldman says she regularly taught yoga to friends in her condo building before getting sickened by listeria on July 2. Now, she has a walker and her body aches. She has headaches and digestive problems.

“I’m kind of depressed,” she says.

“It’s caused me a lot of physical and emotional pain.”

Much of the early days of her illness are a blur. She knows she boarded an ambulance with profuse diarrhea on July 2 and spent five days at North York General Hospital. Afterwards, she remembers Health Canada officials entering her apartment and removing Silk almond milk from her fridge, and volunteers from a community organization giving her sponge baths.

“At my age, 89, I’m not a kid anymore and healing takes longer,” Feldman says.

“I don’t even feel like being with people. I just sit at home.”

Jasmine Jiles and three-year-old Max, Kahnawake Mohawk Territory, Que.

Jasmine Jiles says her three-year-old son Max came down with flu-like symptoms and cradled his ears in what she interpreted as a sign of pain, like the one pounding in her own head, around early July.

When Jiles heard about the recall soon after, she called Danone Canada, the plant-based milk manufacturer, to find out if their Silk coconut milk was in the contaminated batch. It was, she says.

“My son is very small, he’s very young, so I asked what we do in terms of overall monitoring and she said someone from the company would get in touch within 24 to 48 hours,” Jiles says from a First Nations reserve near Montreal.

“I never got a call back. I never got an email”

At home, her son’s fever broke after three days, but gas pains stuck with him, she says. It took a couple weeks for him to get back to normal.

“In hindsight, I should have taken him (to the hospital) but we just tried to see if we could nurse him at home because wait times are pretty extreme,” Jiles says, “and I don’t have child care at the moment.”

Joseph Desmond, 50, Sydney, N.S.

Joseph Desmond says he suffered a seizure and fell off his sofa on July 9. He went to the emergency room, where they ran an electroencephalogram (EEG) test, and then returned home. Within hours, he had a second seizure and went back to hospital.

His third seizure happened the next morning while walking to the nurse’s station.

In severe cases of listeriosis, bacteria can spread to the central nervous system and cause seizures, according to Health Canada.

“The last two months have really been a nightmare,” says Desmond, who has joined the proposed lawsuit.

When he returned home from the hospital, his daughter took a carton of Silk dark chocolate almond milk out of the fridge and asked if he had heard about the recall. By that point, Desmond says he was on his second two-litre carton after finishing the first in June.

“It was pretty scary. Terrifying. I honestly thought I was going to die.”

Cheryl McCombe, 63, Haliburton, Ont.

The morning after suffering a second episode of vomiting, feverish sweats and diarrhea in the middle of the night in early July, Cheryl McCombe scrolled through the news on her phone and came across the recall.

A few years earlier, McCombe says she started drinking plant-based milks because it seemed like a healthier choice to splash in her morning coffee. On June 30, she bought two cartons of Silk cashew almond milk.

“It was on the (recall) list. I thought, ‘Oh my God, I got listeria,’” McCombe says. She called her doctor’s office and visited an urgent care clinic hoping to get tested and confirm her suspicion, but she says, “I was basically shut down at the door.”

Public Health Ontario does not recommend listeria testing for infected individuals with mild symptoms unless they are at risk of developing severe illness, such as people who are immunocompromised, elderly, pregnant or newborn.

“No wonder they couldn’t connect the dots,” she adds, referencing that it took close to a year for public health officials to find the source of the outbreak.

“I am a woman in my 60s and sometimes these signs are of, you know, when you’re vomiting and things like that, it can be a sign in women of a bigger issue,” McCombe says. She was seeking confirmation that wasn’t the case.

Disappointed, with her stomach still feeling off, she says she decided to boost her gut health with probiotics. After a couple weeks she started to feel like herself.

But since then, McCombe says, “I’m back on Kawartha Dairy cream in my coffee.”

This report by The Canadian Press was first published Sept. 16, 2024.

Canadian Press health coverage receives support through a partnership with the Canadian Medical Association. CP is solely responsible for this content.

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B.C. mayors seek ‘immediate action’ from federal government on mental health crisis

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VANCOUVER – Mayors and other leaders from several British Columbia communities say the provincial and federal governments need to take “immediate action” to tackle mental health and public safety issues that have reached crisis levels.

Vancouver Mayor Ken Sim says it’s become “abundantly clear” that mental health and addiction issues and public safety have caused crises that are “gripping” Vancouver, and he and other politicians, First Nations leaders and law enforcement officials are pleading for federal and provincial help.

In a letter to Prime Minister Justin Trudeau and Premier David Eby, mayors say there are “three critical fronts” that require action including “mandatory care” for people with severe mental health and addiction issues.

The letter says senior governments also need to bring in “meaningful bail reform” for repeat offenders, and the federal government must improve policing at Metro Vancouver ports to stop illicit drugs from coming in and stolen vehicles from being exported.

Sim says the “current system” has failed British Columbians, and the number of people dealing with severe mental health and addiction issues due to lack of proper care has “reached a critical point.”

Vancouver Police Chief Adam Palmer says repeat violent offenders are too often released on bail due to a “revolving door of justice,” and a new approach is needed to deal with mentally ill people who “pose a serious and immediate danger to themselves and others.”

This report by The Canadian Press was first published Sept. 16, 2024

The Canadian Press. All rights reserved.

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