Cyclin E, a protein important for DNA replication, is present in various forms of cancer in high levels. Overexpression of cyclin E correlates with increased tumor aggression and reduced breast cancer survival.
Recent findings by MD Anderson researchers showed that detecting cyclin E through a method known as cytoplasmic cyclin staining proved to be a reliable method for detecting breast cancer survival.
Cytoplasmic cyclin staining occurs when scientists add dye to the cytoplasm — the jelly-like substance surrounding the nucleus within the cell membrane — to detect cyclin E levels. The procedure can also distinguish primary cancer cells from the more dangerous metastatic cancer cells.
“Cytoplasmic cyclin E staining identifies patients with the highest likelihood of recurrence consistently across different patient cohorts and subtypes,” said Khandan Keyomarsi, Ph.D., professor of Experimental Radiation Oncology.
Keyomarsi’s team analyzed data from patients with distinct clinical and pathologic features, evaluating the subcellular localization of cyclin E in breast cancer specimens from 2,494 patients from four different cohorts. Data was provided by the National Cancer Institute (NCI), MD Anderson, and the University of Nottingham, Nottingham, UK. Median follow-up times were eight, 13.5, and 5.7 years, respectively.
“Our results showed that cytoplasmic cyclin E staining identified patients with the greatest risk of recurrence better than other prognostic factors," Keyomarsi said. “Cytoplasmic cyclin E staining outperformed all other variables in predicting breast cancer recurrence.
“Our findings provide a rationale for investigating treatment strategies that could specifically target tumors with cyclin E.”