A study found that YAP1 protein expression emerges after treatment, contributing to relapse in small cell lung cancer patients.
RT’s Three Key Takeaways:
- Chemotherapy Resistance Biomarker: Researchers identified that YAP1 protein expression in small cell lung cancer typically appears only after chemotherapy treatment, signaling the development of drug resistance.
- Mechanism of Relapse: The presence of YAP1 allows cancer cells to survive by becoming more invasive and inhibiting programmed cell death, leading to eventual patient relapse.
- Potential Therapeutic Target: Targeting YAP1-expressing cells may offer a new strategy for combination therapies to improve outcomes for patients with aggressive lung cancer.
Some cancer cells express the YAP1 protein only after chemotherapy treatment, allowing them to survive and become more invasive, according to a study published in the Journal of Thoracic Oncology.
This expression leads to treatment resistance and eventual relapse in patients with small cell lung cancer (SCLC), an aggressive disease that initially responds well to chemotherapy but often becomes resistant, researchers from the University of Texas MD Anderson Cancer Center report.
“These findings highlight YAP1-expressing cells as biomarkers of chemotherapy resistance in small cell lung cancer,” said Carl Gay, associate professor of thoracic/head and neck medical oncology. “This brings us another step closer to understanding the mechanisms behind why patients continue to relapse so that we can better adapt our diagnostic and therapeutic strategies to improve patient outcomes.”
YAP1 is a key activator of signaling pathways that promote cell proliferation and inhibit apoptosis, or cell death. When overactivated, it acts as a cancer-promoting oncogene.
The researchers confirmed that untreated SCLC tumors have little to no YAP1 expression, suggesting it is not a subtype-defining feature in untreated cases. Multi-omics analyses revealed that YAP1-positive cells primarily appear after chemotherapy, coinciding with the development of resistance.
In relapse samples, YAP1 expression is frequently present. High expression of the protein may serve as a biomarker for chemotherapy-resistant cell populations, highlighting a potential therapeutic target for combination therapies.
The study authors suggested that further research using other strategies, such as antibody-drug conjugates and T cell engagers, should be conducted to determine if YAP1 emergence is a common result of treatment resistance.
The research was supported by the National Institutes of Health (NIH), the National Cancer Institute (NCI), the Cancer Prevention and Research Institute of Texas (CPRIT), and the Department of Defense, among other organizations.
