Imagine a novel pause button on cancer growth that works in melanoma and colorectal tumors — and cuts growth by nearly 80%. That’s just what Johns Hopkins researchers have discovered by targeting a key enzyme called RNA Polymerase I (Pol I), which is crucial for ribosomal RNA production in cells.
Over more than a decade, scientists including Dr. Marikki Laiho have developed molecules like BMH‑21 and a newer agent named BOB‑42 to block Pol I.
When Pol I is inhibited, cancer cells trigger a stress response that unexpectedly rewires how RNA is spliced — the way instructions are assembled — leading to dramatically slower tumor growth.
In animal models and patient-derived tumor samples, melanoma and colorectal cancers shrank by as much as 77%.
What makes this genuinely special is that many of these tumors carry mismatch repair deficiencies (MMRd), a genetic trait that causes them to resist many existing therapies. These mutations are common in colorectal, stomach, uterine — and melanoma — cancers.
The Pol I inhibitors were especially effective in such hard‑to‑treat types. Dr Laio says:
“Our study reveals that the ribosomal protein RPL22, typically a structural component of the ribosome, plays an unexpected dual role as a critical regulator of RNA splicing”.
Beyond shrinking tumors, this work suggests a two‑for‑one benefit: not only halting cancer growth, but also potentially making tumors more visible to the immune system.
In future therapies, combining Pol I inhibitors with immunotherapy could boost treatment effectiveness — the cancer gets weaker and our own defenses get stronger.
For someone concerned about cancer risk — especially colorectal and melanoma — this research offers real hope. It’s exploring a fundamentally new way to cut tumor growth by attacking the machinery of protein assembly itself, not just the cancer cells.
And since it works in tumors that often resist current drugs, it could pave the way for brand‑new therapies. Plus, the dual impact — growth suppression plus heightened immune recognition — could mean longer remissions, fewer side‑effects, and better outcomes.
Curious for all the fascinating details? Dive into the full Good News Network article and explore the Cell Chemical Biology study to learn how this enzyme‑targeting approach may reshape cancer treatment.
