The TRAIL system is over-expressed in breast cancer and FLIP a marker of good prognosis

• Background Breast cancer is the most common cancer in women. The tumor necrosis factor-related apoptosisinducing ligand (TRAIL) pathway transmits apoptotic signals. Novel anticancer agents that activate this system are in clinical development, including anti-breast cancer. Methods The tissue microarray technique was applied. We used an array of breast cancer tissues from a large group of patients (> 800) to assess the protein expression of TRAIL-R1, TRAIL-R2, the long isoform of FLICE-inhibitory protein and total FLICE-inhibitory protein (FLIPL and FLIPT). Disease-free survival was examined by Kaplan-Meier estimates and the log-rank test. The independence of prognostic factors was determined by Cox multivariate analysis. Results High intra-tumoral expression of all these proteins of the TRAIL pathway was found. The TRAIL receptors and FLIPL were not associated with survival. On univariate analysis, strong FLIPT expression was associated with a significantly better survival (p = 0.001). On multivariate analysis using the Cox proportional hazards model, FLIPT phenotype was significantly associated with a good prognosis in this series (HR 0.52, 95 % CI 0.35-0.78, p = 0.039). Results indicate that this association is valid for all the biological subtypes of breast cancer. The expression of FLIPT was especially high in the luminal subtype, known for its good prognosis. Conclusions These findings support the use of agonistic TRAIL antibodies and drugs targeting FLIP in breast cancer patients. Over-expression of FLIPT but not TRAIL-R1, TRAIL-R2 or FLIPL provides stage-independent prognostic information in breast cancer patients. This indicates a clinically less aggressive phenotype.

Subject headings

MEDICIN OCH HÄLSOVETENSKAP  -- Klinisk medicin -- Cancer och onkologi (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Clinical Medicine -- Cancer and Oncology (hsv//eng)

Keyword

Breast cancer

Tissue microarray

Prognostic factor

TRAIL-R

FLIP

Publication and Content Type

ref (subject category)

art (subject category)