Hyaluronan synthases (HAS1-3) in stromal and malignant cells correlate with breast cancer grade and predict patient survival.

Accumulation of hyaluronan (HA) in pericellular stroma and carcinoma cells is predictive of unfavorable patient prognosis in many epithelial cancers. However, it is not known whether the HA originates from carcinoma or stromal cells, or whether increased expression of hyaluronan synthase proteins (HAS1-3) contributes to HA accumulation. In this study, localization and expression of HAS1-3 were evaluated immunohistochemically in 278 cases of human breast cancer, and correlated with prognostic factors and patient outcome.