While targeted therapies have reshaped treatment for cancers like breast cancer and leukemia, pancreatic tumors remain stubbornly difficult to control.
Having resisted these modern clinical advances, pancreatic cancer patients are reliant on conventional chemotherapy that delivers only modest benefits.
Recently, researchers at Duke-NUS Medical School have identified a molecular mechanism that may help explain why and a potential solution.
Pancreatic cancer ranks among the deadliest malignancies worldwide.
In the U.S. alone, it carries a five-year survival rate of 13%, largely due to late-stage diagnosis, its aggressive spreading and resistance to treatment.
The study, published in the Journal of Clinical Investigation, revolved around a gene called GATA6, which acts as an organizational regulator for pancreatic cancer cells. When GATA6 is active, tumors tend to be more structured and critically more responsive to chemotherapy.
When it goes quiet, cancer cells lose that organization, shifting into a more aggressive form and becoming significantly harder to treat.
A team of researchers at Duke-NUS discovered that most pancreatic cancers carry mutations in a gene called KRAS, which continuously floods cells with growth signals.
Those signals pass through a partner protein known as ERK. When ERK activity runs high, it stabilizes a transcriptional repressor called JUNB, which then binds directly to the GATA6 gene and suppresses it. This essentially locks the tumor into its more aggressive, treatment-resistant state.
Luckily, the process is reversible. When researchers blocked the KRAS-ERK pathway using targeted inhibitors, JUNB broke down and GATA6 levels rebounded. Cancer cells then shifted back to a more organized and chemotherapy-sensitive state.
“By identifying the pathway that suppresses GATA6, we now have a clearer picture of how tumors become resistant — and potentially how to reverse that process,” David Virshup, the study’s lead author, said.
The researchers also tested what happens when the reversal is combined with chemotherapy. In both tests, combining standard-of-care chemotherapy with KRAS-ERK inhibitors produced stronger effects than either approach alone.
Most importantly, that effect depended on GATA6 being present. When the gene was experimentally knocked out, the benefit of combining the two largely disappeared, confirming the importance of GATA6 in the process.
Professor Shee-Mei, interim vice-dean for research at Duke-NUS, said that the findings “offer a rational strategy for combining targeted therapies with existing drugs,” a meaningful development given how few new approaches have moved the needle for pancreatic cancer patients.
The implications may extend to other cancers driven by KRAS mutations.
Lung and colorectal cancers share many of the same drivers, giving researchers a clearer framework for testing whether the same suppression of cell organization plays a role in their resistance to treatment as well.
For pancreatic cancer, the findings raise an immediate clinical question — whether pairing KRAS-ERK inhibitors with existing chemotherapy can replicate those results in patients.
Further studies will be needed to determine whether the combination is safe and effective in patients.
However, the approach could give oncologists a more targeted weapon against one of medicine’s most treatment-resistant cancers.
