
A new approach to cancer immunotherapy Study highlights a promising strategy for blocking an off switch on immune cells.
August 13, 2021
LA JOLLA, CA A team headed by scientists at Scripps Research has devised an immune cell-boosting technique that may enable potent new cancer treatments.
The scientists, whose work is described in ACS Central Science, found a way to target Siglec-7, a protein that normally acts like an off-switch on immune cells called human natural killer (NK) cells.
NK cells are natural cancer-fighters, and researchers have been exploring ways to use them as cancer treatments, but many tumors have the ability to blunt NK cell attacks by exploiting off-switches such as Siglec-7.
The scientists showed, however, that by adding relatively small doses of a designer, sugar-like molecule that binds to Siglec-7 proteins, they could induce the release of the Siglec-7 proteins from NK cells, boosting their tumor-killing power.
In principle, we could treat NK cells in this way to reduce their Siglec-7 proteins, thus increasing their anti-tumor potency before the cells are infused therapeutically into cancer patients, says study senior author Peng Wu, PhD, associate professor in the Department of Molecular Medicine at Scripps Research.
Tumors commonly defend themselves from immune attack by producing molecules that effectively shut down immune cells in their vicinity. They often achieve this by exploiting off-switch or dimmer-switch mechanisms that exist on immune cells mechanisms that normally help keep immune cells from becoming overactive and causing unnecessary damage to healthy tissues in the body.
The Importance of Blocking Off-Switches
Scientists in recent decades have begun uncovering these off-switch or dimmer-switch pathways, and developing treatments that block them to boost the immune system's cancer-fighting ability. For example, drugs that block the so-called PD-1 off-switch, on immune cells called T cells, have had astounding successes in some cases, curing patients who had advanced, metastatic cancers. But most tumors are not completely killed by such treatments and that has prompted scientists to look for other off-switches that such tumors may be exploiting.
Siglec proteins, which appear on many immune cells, are now suspected of being among the off-switches that tumors exploit to withstand PD-1 blockers and other cancer immunotherapies. Scientists therefore are racing to find ways to block Siglecs too.
Siglec-7s are the dominant Siglecs on NK cells. Wu and his colleagues found in their study that they could reduce the quantity of Siglec-7 proteins on NK cells by adding small doses of a sugar-like molecule called FTMCNeu5Ac an engineered version of the sugar-like molecule that tumor cells normally use to activate Siglec-7 and shut down NK cells. At the right dose range, the reduction of Siglec-7 brought about by FTMCNeu5Ac dramatically boosted the ability of NK cells to kill cancer cells in lab-dish cultures suggesting this approach as one that might be used to super-charge NK cell-based cancer therapies.
A Surprise Finding
The study also included a surprising and important finding on the basic biology of Siglec-7 in the context of NK cell encounters with cancer cells. Scientists studying Siglec proteins have widely assumed that cancer cells naturally tend to produce large quantities of Siglec-7-binding molecules ( ligands ) in order to defeat NK cells wherever they encounter them. However, Wu and colleagues found otherwise.
It's not the case that tumor cells naturally have high numbers of Siglec-7 ligands and normal cells do not, Wu says. We found instead that tumor cells typically have normal numbers of Siglec-7 ligands, and only get more of these ligands as a defensive response when they actually encounter an NK cell.
Wu and his colleagues are now working to develop their Siglec-7-reducing, NK-cell-boosting strategy, and to see if a similar approach will work with other types of Siglec protein on other immune cells. They are collaborating in this effort with the laboratory of Matt Macauley, Ph.D. at University of Alberta and the laboratory of James Paulson, PhD, Cecil H. and Ida Green Professor and Co-Chair of the Department of Molecular Medicine at Scripps Research, and developer of the Siglec-7-binding ligand used in the study.
Modulation of Siglec 7 Signaling Via In Situ-Created High-Affinity cis-Ligands was co-authored by Senlian Hong, Chenhua Yu, Emily Rodrigues, Yujie Shi, Hongmin Chen, Peng Wang, Digantkumar Chapla, Tao Gao, Ruoxuan Zhuang, Kelley Moremen, James Paulson, Matthew Macauley, and Peng Wu.
Funding was provided by the National Institutes of Health (R01AI154138, P41GM103390, P01GM107012, R01GM130915, R01AI050143, P01HL107151, and U19AI136443).
Cancer Molecular Medicine Wu, Peng
Most recent headlines
11/12/2025
Dalet, a leading provider of cloud-native, end-to-end media workflow solutions, ...
28/11/2025
Nadia Fall attends the 2025 Sundance Film Festival premiere of Brides at the Egyptian Theatre on January 24, 2025, in Park City, Utah. (Photo by Donyale West/...
28/11/2025
It's easy to ignore those little red update available badges. But when it ...
28/11/2025
WASHINGTON Federal Communications Commission has released a tentative agenda for the December Open Commission Meeting scheduled for Thursday, December 18, 2025 ...
28/11/2025
The Professional Fighters League is looking to super-serve fans of mixed martial...
28/11/2025
Fubo has released in beta on select Roku devices a new feature that lets users display up to four simultaneous streams at once....
28/11/2025
The WNBA playoffs and Week 4 of the NFL regular season highlight the list of live sports events airing on television this weekend....
28/11/2025
The 32nd class of honorees to the B+C Hall of Fame took to the stage at New York's Ziegfeld Ballroom on September 26 for a gala induction event. Click below...
28/11/2025
We hold in our hands the very last Next Text for Next TV, the weekly back-and-fo...
28/11/2025
DirecTV said it made a deal with EchoStar to buy EchoStar's video businesses, including satellite-TV provider Dish TV and virtual MVPD Sling TV, for $1 plus...
28/11/2025
The Broadcasting+Cable Hall of Fame, the premier industry event paying tribute to the influencers, innovators and shining lights of broadcast, cable and streami...
28/11/2025
Friday 28 November 2025
Sky Sports x Slawn drop limited-edition football jersey...
28/11/2025
Rohde & Schwarz shows resilience in a challenging environment, revenue exceeds t...
28/11/2025
Unwrapped: The Toy Show Appeal - airing this Sunday on RT One and RT Player- s...
27/11/2025
LONDON Vizrt has added several AI-driven advanced features offering improved speed, intelligence and accuracy in the newest version of its media asset managemen...
27/11/2025
Prime Video has launched AI-powered video season recaps in a beta version for select English-language Prime Original series in the U.S., a move Amazon is callin...
27/11/2025
Back to All News
Netflix's Raat Akeli Hai: The Bansal Murders Marks a Grand...
27/11/2025
27 Nov 2025
GSMA brings M360 Eurasia 2026 to Samarkand in partnership with VEON...
27/11/2025
Tahar Rahim and Izuka Hoyle star in the gripping six-part Sky Original from Acad...
27/11/2025
Thursday 27 November 2025
Sky Arts Reveals the Nation's Greatest Basslines - and Queen Reign Supreme
The UK's most iconic basslines have been revealed...
27/11/2025
Back to All News
Stranger Things 5': Prepare for One Last Adventure With O...
27/11/2025
The media industry has a paradox at its core. It's an industry built on light, color and imagination, yet behind the scenes, it's powered by one of the ...
27/11/2025
Rating reflects rating progress across areas including policies, diversity & inclusion, health & safety and Net Zero leadership
Winchester, UK, 27 November 202...
27/11/2025
What are the industry standards for Retail Media? Kathryn explains that certification is based on the IAB Europe Retail Media Measurement Standards and the IAB ...
27/11/2025
World champion boxer and Irish sporting icon Katie Taylor will be in studio this...
27/11/2025
Roblox, one of the world's most popular online gaming platforms for primary ...
27/11/2025
Black Friday is leveling up. Get ready to score one of the biggest deals of the season - 50% off the first three months of a new GeForce NOW Ultimate membership...
26/11/2025
SVG Sit-Down: Prime Video EP Mike Muriano Previews Massive Black Friday Slate Fe...
26/11/2025
A cinematic snow sculpture at the 1995 Sundance Film Festival. Photo by Randall Michelson...
26/11/2025
Book podcasts are booming. On Spotify, you'll find everything from celebrity book clubs to deep dives with bestselling authors. And in markets where audiobo...
26/11/2025
Mumbai, November 24, 2025: In a first-of-its-kind initiative, JioStar, in collab...
26/11/2025
LONDON Factual content producer ITN Productions has launched a new low-latency IP gallery for news bulletins....
26/11/2025
MIAMI TelevisaUnivision said it struck a new multiyear distribution agreement with YouTube TV that includes distribution of TelevisaUnivision's U.S. network...
26/11/2025
OpenDrives, Inc., a leader in software-defined data storage and data services, today announced the launch of the Atlas Corporate Creative Solution. This new Atl...
26/11/2025
Disguise, the industry-leading company powering the world's biggest live performances, is partnering with pioneering LED wall manufacturer DVS to give atten...
26/11/2025
HighField AI, the pioneer in agentic and multimodal automation for broadcast and media production, today announced the expansion of its global channel partner n...
26/11/2025
As high-stakes Premier League fixtures approach and additional premium content launches, with MONO positioning themselves to dominate Thailand's sports stre...
26/11/2025
Hosting a wide variety of events from high-intensity NHL games to complex live music concerts and major entertainment productions, Montreal's 21,000 capacit...
26/11/2025
Vizrt, the leader in live production technology revolutionizing viewer engagement and experience, releases AI-driven advances focusing on speed, intelligence, a...
26/11/2025
ITN Productions, an award-winning factual content producer, today launched a new low-latency IP gallery for news bulletins. Responsible for delivering a leading...
26/11/2025
Ikegami reports ongoing advances throughout 2025 in developing and delivering coordinated television production solutions that maximize quality, versatility and...
26/11/2025
Following the Nov. 21 blackout of NBCUniversal channels on Fubo, the two sides have traded barbs about their inability to reach a new carriage deal....
26/11/2025
LONDON As TV sports rights become increasingly important for both broadcasters and streamers, Ampere Analysis predicts global investment in the genre will surpa...
26/11/2025
LOS ANGELES Vubiquity said it has achieved the Amazon Web Services (AWS) Media & Entertainment Competency as part of the AWS Partner Network (APN). This designa...
26/11/2025
WASHINGTON The Federal Communications Commission's Enforcement Bureau said it has entered into a consent decree with Comcast calling for the cable company t...
26/11/2025
Berklee Named to the Hollywood Reporters Top Music Schools List The publication highlights the college's screen scoring program, industry partnerships, and ...
26/11/2025
Back to All News
Animated Series Love Through a Prism' Casts New Light on ...
26/11/2025
Back to All News
NALIP Unveils Fifth Cohort of Director Incubator
Social Impact
26 November 2025
United States
Link copied to clipboard
The National Assoc...
26/11/2025
YouView Achieves Greenly Gold Certification for SustainabilityNov 26, 2025
YouView is proud to announce a Gold Certification award from Greenly for our perform...