Breakthrough at Kanazawa University: Wnt Signaling's Role in Gastric Cancer Metastasis

Researchers at Kanazawa University's Nano Life Science Institute (NanoLSI) and Cancer Research Institute have uncovered a critical mechanism behind gastric cancer's aggressive spread. Published in Nature Communications on February 14, 2026, the study reveals how Wnt signaling—activated by ligands secreted from tumor cells—reshapes the surrounding tissue to foster metastasis, particularly to the liver. Led by Yuichiro Furutani and Hiroko Oshima under principal investigator Masanobu Oshima, this work highlights Japan's forefront position in oncology research.

Gastric cancer, or stomach cancer, remains a major health challenge in Japan, where advanced screening has reduced incidence but metastasis still claims many lives. This discovery shifts focus from cancer cells alone to their interaction with the tumor microenvironment, opening doors for novel therapies.

Demystifying Wnt Signaling: The Pathway Explained

Wnt signaling refers to the Wingless-related integration site (Wnt) pathway, a fundamental biological process regulating cell proliferation, differentiation, and migration during embryonic development and tissue homeostasis. In full, it involves secreted glycoproteins (Wnt ligands) binding to receptors on target cells, stabilizing β-catenin, which enters the nucleus to activate transcription factors like TCF/LEF, promoting genes for growth and survival.

In cancer, aberrant Wnt activation—often ligand-dependent rather than mutational—drives tumor progression. Step-by-step: (1) Cancer cells secrete Wnt ligands; (2) Ligands bind Frizzled/LRP5/6 receptors on nearby stromal cells; (3) Dishevelled inhibits the destruction complex (Axin, APC, GSK3β, CK1); (4) β-catenin accumulates and translocates to nucleus; (5) Gene expression changes support tumor growth. Unlike canonical mutation-driven Wnt (e.g., APC loss), ligand-dependent Wnt relies on paracrine signaling, crucial for metastasis as shown in this study.

Gastric Cancer Burden in Japan: Statistics and Screening Success

Japan boasts one of the world's highest gastric cancer incidences historically, at 27.6 cases per 100,000, though declining due to Helicobacter pylori eradication and endoscopy screening. In 2026, it ranks as the fifth leading cancer cause, with 64% five-year survival for early detection but dropping sharply for metastatic cases. Projections indicate continued decrease, yet ~132,588 new cases persist annually, underscoring research urgency.

Kanazawa University's work aligns with national efforts like the Cancer Moonshot program, emphasizing microenvironment-targeted therapies amid Japan's aging population.

Innovative Mouse Models and Organoids: The Study's Methodology

The team engineered sophisticated mouse models: KTP mice (Kras^G12D, Tgfbr2^-/-, Trp53^-/-) develop metaplasia, while WKTP (adding Wnt1 expression) form dysplastic tumors. Organoids from gastric epithelium mimicked human pathology precisely.

Splenic transplantation tested metastasis: WKTP organoids produced multiple liver tumors; KTP did not. APC disruption in KTP failed to induce mets, proving stromal Wnt essential. Single-cell RNA-seq and imaging revealed fibroblast activation, Has2 upregulation, and hyaluronan (HA) deposition.

Cancer Cells Remodel the Microenvironment: Step-by-Step Mechanism

1. Gastric cancer cells secrete Wnt ligands (e.g., Wnt1).
2. Ligands activate Wnt in stromal fibroblasts and cooperate with TGF-β signaling.
3. Activated fibroblasts become cancer-associated fibroblasts (CAFs), upregulating Has2 (hyaluronan synthase 2).
4. Excessive HA accumulates extracellularly, forming a hydrated niche shielding cancer cells from immune attack and aiding adhesion/proliferation.
5. In liver, HA-rich stroma supports secondary tumor establishment.

HA degradation via hyaluronidase in models slashed metastasis, validating the pathway.

• Benefits of targeting stroma: Reduced resistance vs. direct tumor kill.
• Risks: Off-target effects on normal Wnt/HA functions.

Photo by Markus Winkler on Unsplash

Hyaluronan: The Metastatic Glue and Therapeutic Target

Hyaluronan (HA), a glycosaminoglycan, maintains tissue hydration and signaling. In cancer, overexpression creates desmoplastic stroma favoring invasion. Kanazawa's findings pinpoint Has2-driven HA as metastasis enabler, with hyaluronidase blocking liver colonization.

Real-world cases: High HA correlates with poor gastric cancer prognosis in Japanese cohorts. Ongoing trials explore HA inhibitors like pegvorhyaluronidase alfa.

Therapeutic Promise: Disrupting the Metastatic Niche

Oshima notes: "Disrupting the environment that supports metastasis could be a powerful new therapeutic approach." Strategies: Wnt ligand traps (e.g., Foxy-5), Has2 inhibitors, HA-degrading enzymes. Japan's precision medicine push, via AMED funding, accelerates translation.

Stakeholder views: Oncologists praise microenvironment focus; patients hope for better outcomes amid 2026 survival rates hovering at 64%.

Nano Life Science Institute (NanoLSI): Japan's Nanotech Frontier

NanoLSI, a WPI center since 2018, pioneers nanoscale imaging for life sciences. Cancer research thrives via advanced microscopy revealing protein dynamics. Funded by MEXT/AMED, it fosters interdisciplinary teams, producing high-impact papers like this Wnt study.

Collaborations with Singapore's IMCB enhance global reach. NanoLSI trains postdocs/PhDs in cutting-edge tools, positioning Kanazawa as biotech hub.

Spotlight on Masanobu Oshima and the Research Team

Masanobu Oshima, Professor in Genetics, specializes in gastrointestinal cancers using genetically engineered mice. His lab's Wnt/COX-2 models pioneered metaplasia-to-cancer progression. Furutani (GI surgeon) bridges clinic-lab; Hiroko Oshima excels in organoids.

Team's timeline: Kras/Tgfbr2/Trp53 model (2013) → Wnt integration (2026 breakthrough). Their work exemplifies Japan's researcher excellence.

Kanazawa University and Japan's Oncology Ecosystem

Kanazawa University, Ishikawa's flagship, excels in medicine (Cancer Research Institute). Amid declining gastric cancer via screening, focus shifts to metastasis. National initiatives like Moonshot R&D fund such studies, with Kanazawa securing Grants-in-Aid (22H00454).

Stats: Japan leads endoscopy screening (70% participation), cutting mortality 50% since 1980s. Future: AI/nano integration for early detection.

Photo by julien Tromeur on Unsplash

Careers in Cancer Research: Opportunities at Kanazawa and Beyond

NanoLSI offers postdoc positions in advanced imaging/organoids, ideal for PhDs in molecular biology. Japan's biotech boom demands experts in Wnt pathways. Salaries: ~¥6-10M for postdocs, ¥12M+ professors.

• Skills: Organoid culture, scRNA-seq, mouse genetics.
• Benefits: International collab, state-of-art facilities.
• Risks: Competitive funding, language barrier (English OK at NanoLSI).

Future Outlook: Transforming Gastric Cancer Treatment

Kanazawa's Wnt-HA discovery promises microenvironment therapies, complementing Japan's screening prowess. Ongoing human validation and trials could boost survival beyond 64%. For researchers/students, it underscores Japan's vibrant higher ed cancer scene—join via university jobs, higher ed roles, or career advice.