From cutting-edge cancer research to elite trail running, UC San Francisco’s Patrick “Paddy” O’Leary, PhD, rises to the challenges of a well-balanced life.

The native of Wexford, Ireland, is a senior research specialist in the laboratory of Alan Ashworth, PhD, president of the UCSF Helen Diller Family Comprehensive Cancer Center at Mission Bay.

Since 2018, O’Leary has led collaborative projects with academic and industry partners, primarily using CRISPR gene editing and high content screening to map genetic vulnerabilities in cancer. His recent projects include genetic and protein interaction mapping, evaluating anti-tumor activity and defining genetic vulnerabilities in gastro-esophageal and other types of cancer, among others during the COVID-19 pandemic with the Antiviral Drug Discovery Centers for Pathogens of Pandemic Concern and the QBI Coronavirus Research Group. He's also a mentor for junior researchers, providing guidance and technical training for postdoctoral, junior specialist, undergraduate and high school projects.

But that’s just the tip of the iceberg in O’Leary’s life. In addition to his research at UCSF, he is a world-class runner.

Sponsored by The North Face, O’Leary gets up for training most days at 6 a.m., logging anywhere from four to 50 miles outside of competition in places like Mount Sutro, Twin Peaks, Golden Gate Park and the Marin Headlands. “My sweet spot is about 70 miles per week,” O’Leary said. His mileage in competition is a different story altogether, as O’Leary has conquered races as short as a 5K and as long as 100 miles, traversing over sometimes dangerous mountainous terrain in remote places.

“Sure these races are painful, but they're really fun,” O’Leary laughed.

Paddy O’Leary runs towards San Fransisco skyline
UCSF oncology scientist Paddy O'Leary runs near the San Fransisco bridge
Patrick O'Leary runs alongside a green highway
Paddy O’Leary's orange shoes running in mud
Photos by Tony DiPasquale

Conquering the Dipsea Race

In mid-June, he beat about 1,500 other competitors in the treacherous and challenging Dipsea Race in Marin County. The 7.4-mile race from Mill Valley to Stinson Beach is the oldest trail race in America and hosts runners from around the world, routing them through a series of forested trails, steep hills and a network of staircases that leave legs burning for days on end. “The race is a great equalizer,” O’Leary said of Dipsea’s unique handicapped start times, which level the playing field for all ages across the diverse set of competitors. The oldest and youngest competitors start 25 minutes before young adults, and women start a few minutes before men. In the end, the first person across the finish line is still the winner. His clock time of 47:23 was an improvement of 1:40 from his time in the 2022 race, and he crossed the finish line ahead of the five female runners who took the 2nd to 6th places.

That’s a big improvement from his debut Dipsea Race when O’Leary came in 499th in 2019.

A challenge for the debut runners is the 25-minute penalty given on top of age and gender handicap minutes. Runners must finish in the top 50% to qualify for the invitational section the following year. Without the 25-minute debut penalty, O’Leary worked his way up to 10th in 2021 and 2nd in 2022.

It doesn’t stop there for the elite mountain and ultrarunner, either. He’s also a freelance film producer, helping bring audiences a taste of his passion as part of award-winning outdoor and adventure documentary film projects – one on the Irish mountain running community, “Coming Home – Ag Teacht Abhaile,” and one on the urban trails of San Francisco, “Urban Oasis – A Love Letter to San Francisco.”

Video by Gillian Grisman

Coming to UCSF

Outside of a few short internships in North America and some trips here with the Ireland National Lacrosse team, O’Leary had hardly spent any time in the U.S. before moving here. But the job at UCSF quite literally changed his life.  

“I happened to see a poster with the picture of the Golden Gate Bridge,” he said of the UCSF job posting.

I knew UCSF was a leading health care institution, but hadn’t worked with them before. Once in San Francisco, I fell in love with the city. 

Patrick O'Leary, PhD

O’Leary initially planned to be in San Francisco for 2 to 3 years.

In 2013, he joined the UCSF laboratory of Martin McMahon, PhD, focusing his research as a postdoctoral scholar on RAF-mutated melanoma and lung cancers. As a way to make friends outside of the cancer lab, he took up running at 25 and joined the November Project, an early morning San Francisco-based workout group featuring a number of UCSF peers. That’s where he discovered a natural talent for trail running, a sport he’d never tried before but soon enjoyed.

“It’s how I got to explore our city,” he added.

With that, he was off and running. O’Leary ran his first trail race in 2015, signing with The North Face just a year later.

Work with the outdoor performance outfitter has taken O’Leary all over the globe to race in various competitions and championships alongside some of the world’s best. On top of all that, he accomplished an impressive feat in 2019, racing on five continents in a calendar year from Hong Kong, Cape Town and Patagonia to his home country of Ireland.

Yet somehow O’Leary is able to excel in each endeavor.

“It's really challenging, I'm not going to lie,” he said.

Finding balance

His colleagues are awed by O’Leary’s commitment to both. "Even more impressive than Paddy’s ability to balance professional running and performing impactful research is that he is also a kind and supportive co-worker, always going out of his way to help others," said Rachel Abrams, PhD. Abrams, like O’Leary, is a senior research specialist at the Helen Diller Family Comprehensive Cancer Center.

"Paddy is a great example that it is possible to balance outside interests and responsibilities while still contributing to science," she added.

O’Leary finds it easy to keep going with the Bay Area as his playground.

“We’re so fortunate living here in San Francisco,” he described. “Every person has a public park within a half mile of their house. It’s something that people don’t realize. Getting to the outdoors is so important. It’s a huge health issue across Western society. I’ve made it my mission to tell the people of San Francisco what we have here.” As he puts it, the Irishman has “intellectual pursuits as well as…athletic pursuits,” a give-and-take relationship he’s come to terms with lately as a symbiotic one.

It should be elevated more. People should have something they’re passionate about outside of science. It’s so important to have balance.

Patrick O'Leary, PhD

“I always talked about my athletics holding back my science and my science holding back my athletics,” he said of his younger self.

These days, O’Leary uses one to fuel the other.

“I get to meet people from all over the world in the racing scene and I organize events, that interaction skill set is really important,” he said. 

For now, O’Leary will continue with his work in the cancer and virology research groups at UCSF’s Mission Bay campus, producing documentary films and, of course, trail running. The 2023 Dipsea Race champion plans to enter the famous Northern California race again next year, albeit with a one-minute penalty assessed against his total time via the Dipsea handicap system. 

“I’m doing this race every year as long as I can,” he said. “If I’m still doing this in my 70s, I’ll be so grateful.”

Scientist O'Leary runs through dirt road towards sunrise
Photo by Tony DiPasquale