In a groundbreaking discovery, scientists in Singapore have uncovered a hidden defense mechanism that allows lung cancer cells to resist treatment, and it's all linked to a gene called EGFR. But here's the catch: this revelation is both a blessing and a curse, as it highlights a critical challenge in cancer treatment.
Singapore's A*STAR IMCB researchers have published a study in Science Advances (https://www.science.org/doi/10.1126/sciadv.adv3980) that sheds light on why some lung cancer cells become treatment-resistant. The culprit? Mutations in the EGFR gene, which plays a crucial role in cell growth and division. These mutations are prevalent in Southeast Asia, affecting 40-60% of a specific lung cancer type called adenocarcinoma. Initially, targeted drugs show promise, but eventually, the cancer cells find a way to fight back.
The mystery lies in the stability of the faulty proteins produced by mutant EGFR. Normally, proteins are recycled and degraded, but these mutant proteins stick around, causing cancer's relentless growth. And this is the part most people miss—the cancer cells' secret weapon.
Through an extensive genome-wide screen, the researchers identified a clever survival tactic. Cancer cells release ATP, an energy molecule, in large quantities. This triggers the activation of the P2Y2 receptor, which then teams up with integrin β1 to create a protective shield around the mutant EGFR. This barrier prevents the faulty protein from being recycled, allowing it to keep the cancer alive and thriving.
The researchers confirmed this mechanism in human lung cancer patients, finding elevated levels of P2Y2 and integrin β1 in tumour tissues. Dr. Gandhi Boopathy, a senior scientist, likened this process to molecular 'bodyguards' protecting the mutant protein. Interestingly, P2Y2's location on the cell surface makes it an accessible target for potential drugs.
The team's experiments revealed that disabling this protective system could be a game-changer. By removing the P2Y2 receptor, they witnessed a dramatic decrease in the mutant EGFR protein. Furthermore, a natural compound called kaempferol, found in leafy greens, showed remarkable results in shrinking drug-resistant lung tumours in laboratory models. This treatment specifically targeted cancer cells with EGFR mutations, leaving normal cells unharmed.
Professor Wanjin Hong, a renowned cancer research leader, emphasized the significance of this approach. By targeting the P2Y2 system, they aim to dismantle the very foundation that keeps mutant EGFR stable. This strategy could potentially enhance the effectiveness of current drugs and even prevent resistance from developing in the first place.
This study, led by Prof. Hong and involving a talented PhD student, Yafei Du, is a collaborative effort across multiple research institutions in Singapore, Taiwan, and France. It opens up a new avenue in the ongoing battle against drug-resistant cancer, but it also raises questions: Could this be the long-awaited breakthrough in cancer treatment? Or will cancer find yet another way to outsmart our defenses? The debate is open, and the quest for answers continues.
