Researchers at Houston Methodist have identified a molecular driver that appears to contribute to treatment resistance in advanced hormone receptor-positive breast cancer, a finding that could eventually expand opportunities for clinical laboratories involved in precision oncology testing and biomarker development. The study, published in Clinical Cancer Research, identified a signaling pathway that may help explain why some tumors stop responding to endocrine therapies, opening the door to new diagnostic and therapeutic strategies.
Hormone receptor-positive breast cancer accounts for about three-quarters of all breast cancer cases, according to the American Cancer Society. Endocrine therapy is a standard treatment for these tumors, although many patients with advanced disease eventually develop treatment resistance. According to the Houston Methodist research team, blocking the newly identified target restored treatment sensitivity in laboratory models, suggesting the pathway could someday serve as both a therapeutic target and a predictive biomarker.
If validated in clinical studies, the discovery could ultimately influence how laboratories help identify patients who are most likely to benefit from emerging targeted therapies.
“Our study suggested that S100–RAGE signaling may indicate early resistance to this drug and that even drug combination therapies may be less effective. But the exciting part is that this pathway appears targetable,” said Stephen Wong, PhD, the John S Dunn Presidential Distinguished Chair in Biomedical Engineering and professor of Radiology and Medicine at Houston Methodist.
“Using therapeutic options to block the signaling pathway made the cancer cells sensitive to early-line treatment. In metastatic lab models, therapeutic combination with this early treatment significantly reduced metastatic lesion number, lesion size and overall tumor burden,” Wong also noted.
Potential diagnostic opportunities
For clinical laboratories, the findings underscore the continuing evolution of precision oncology beyond identifying inherited or tumor mutations. As researchers uncover additional molecular mechanisms responsible for drug resistance, pathology laboratories and molecular diagnostics providers may be called upon to develop assays capable of detecting these resistance markers.
Such testing could help oncologists determine which patients are most likely to respond to new therapies designed to overcome endocrine resistance or identify candidates for clinical trials evaluating those treatments.
The findings also reflect a broader trend in oncology in which laboratories play an increasingly central role in treatment selection. Companion diagnostics, next-generation sequencing panels, immunohistochemistry, and other molecular assays have become essential components of personalized cancer care. As researchers continue to identify biomarkers linked to treatment resistance, laboratories may have additional opportunities to expand their testing menus and support more individualized therapeutic decisions.
Although the Houston Methodist research remains at the preclinical stage, it illustrates how discoveries in cancer biology often lay the groundwork for future diagnostic innovation. If subsequent studies confirm the target's clinical value, diagnostic developers and clinical laboratories could eventually develop assays that help physicians identify patients whose tumors are likely to resist endocrine therapy, further strengthening the laboratory's role in precision oncology.
This article was created with the assistance of Generative AI and has undergone editorial review before publishing.
