HOUSTON — Researchers have identified a naturally occurring protein that appears to suppress the spread of pancreatic cancer cells to neighboring tissue and distant organs, a finding that scientists say could point toward a new class of treatments for one of the deadliest and most treatment-resistant malignancies in modern oncology.
The protein, designated PANK-3 by the research team, was found to interfere with the molecular signaling cascade that pancreatic ductal adenocarcinoma cells use to dissolve surrounding tissue barriers and enter the bloodstream for transport to secondary sites. In laboratory cell cultures and in mouse models, introducing elevated concentrations of PANK-3 reduced measurable metastatic spread by 71 percent compared with untreated control groups, according to a study published Thursday in the journal Cancer Research Frontiers.
“What is notable about PANK-3 is that it appears to act at multiple steps in the metastatic process, not just one,” said Dr. Valentina Ruiz, a molecular oncologist at the Hargrove Cancer Center in Houston and the study’s lead author. “It disrupts cell adhesion, it disrupts migration across tissue boundaries, and it appears to impair the formation of pre-metastatic niches in the liver — the primary site of pancreatic cancer spread in most patients.”
Pancreatic cancer carries a five-year survival rate below 12 percent in most high-income countries, largely because it is rarely detected before malignant cells have already spread beyond the pancreas. The vast majority of deaths result not from the primary tumor but from metastatic disease, particularly in the liver, lungs, and the peritoneal lining of the abdomen, where secondary tumors are exceptionally difficult to treat surgically or with existing systemic therapies.
The study team conducted a retrospective analysis of tissue samples collected from 214 patients who had undergone surgical resection of primary pancreatic tumors at three affiliated medical centers. Patients whose tumor tissue showed higher natural expression levels of PANK-3 had a median overall survival of 24 months following surgery, compared with 14 months in patients with low PANK-3 expression, after the data were adjusted for tumor stage, lymph node involvement, margin status, and post-operative treatment regimen.
Ruiz and her colleagues cautioned that translating the finding into an approved clinical therapy will require substantial additional development work across several years. PANK-3 is a large, complex protein that cannot be formulated as a conventional small-molecule oral drug and delivered to tumor sites at therapeutic concentrations through standard routes. Delivery mechanisms currently under investigation include messenger RNA therapies similar to those developed for vaccines, engineered viral vectors that instruct cancer cells to produce their own PANK-3, and modified adoptive cell therapy approaches — all of which have shown varying degrees of feasibility in other cancer contexts.
“Each of these delivery platforms has its own risk profile and its own manufacturing complexity,” Ruiz said. “We are not at a point where we can tell patients this discovery will change their treatment options in the near term. But we believe it opens a mechanistic door that was not open before.”
Dr. Elias Fontaine of the International Society of Oncological Research, who reviewed the study but was not part of the research team, described the discovery as “a genuinely exciting mechanistic lead” in a disease area with few promising new targets in recent years. He cautioned, however, that the history of cancer biology is filled with proteins that suppressed tumor behavior in mouse models but failed to replicate those effects in human clinical trials.
The Hargrove team has filed for a provisional patent covering therapeutic applications of PANK-3 and its synthetic analogs. Ruiz said the team is in early discussions with two pharmaceutical companies about co-funding a Phase I safety and dosing trial in patients with locally advanced pancreatic cancer, which she estimated could begin within two years if negotiations proceed on schedule and regulatory filings are accepted without significant revision.