PRECLINICAL STUDY Hyaluronan synthases (HAS1–3) in stromal and malignant cells correlate with breast cancer grade and predict patient survival Pa ¨ivi Auvinen • Kirsi Rilla • Ritva Tumelius • Markku Tammi • Reijo Sironen • Ylermi Soini • Veli-Matti Kosma • Arto Mannermaa • Jukka Viikari • Raija Tammi Received: 24 October 2013 / Accepted: 3 December 2013 / Published online: 14 December 2013 Ó Springer Science+Business Media New York 2013 Abstract Accumulation of hyaluronan (HA) in pericel- lular stroma and carcinoma cells is predictive of unfavor- able patient prognosis in many epithelial cancers. However, it is not known whether the HA originates from carcinoma or stromal cells, or whether increased expres- sion of hyaluronan synthase proteins (HAS1–3) contributes to HA accumulation. In this study, localization and expression of HAS1–3 were evaluated immunohisto- chemically in 278 cases of human breast cancer, and cor- related with prognostic factors and patient outcome. Both carcinoma cells and stromal cells were HAS-positive. In carcinoma cells, HAS1 and HA stainings correlated with each other, and HAS1 associated with estrogen receptor negativity, HER2 positivity, high relapse rate, and short overall survival. In stromal cells, the staining levels of all HAS isoforms correlated with the stromal HA staining, stromal cell CD44, high relapse rate, and short overall survival of the patients. In addition, expression levels of stromal HAS1 and HAS2 were related to obesity, large tumor size, lymph node positivity, and estrogen receptor negativity. Thus, stromal HAS1 and HAS3 were indepen- dent prognostic factors in the multivariate analysis. The data suggest that increased levels of HAS enzymes con- tribute to the accumulation of HA in breast cancer, and that HA is synthesized in carcinoma cells and stromal cells. The study also indicates that HAS enzyme levels are related to tumor aggressiveness and poor patient outcome represent- ing potential targets for therapy. Keywords Breast cancer Á Hyaluronan synthase Á HER2 Á Obesity Abbreviations HA Hyaluronan Has, HAS Hyaluronan synthase gene and protein bHABC Biotinylated hyaluronan binding complex HR Hazard ratio TSG-6 Tumor necrosis factor alpha stimulated gene-6 IaI Inter alpha inhibitor UDP Uridine diphosphate RAR Retinoic acid receptor STAT Signal transducer and activator of transcription NF-kB Nuclear factor kappa-light-chain-enhancer of activated B cells CREB cAMP response element binding protein CISH Chromogenic in situ hybridization BMI Body mass index Electronic supplementary material The online version of this article (doi:10.1007/s10549-013-2804-7) contains supplementary material, which is available to authorized users. P. Auvinen (&) Department of Oncology, Cancer Center, Kuopio University Hospital, P.O. Box 100, 70029 Kuopio, Finland e-mail: paivi.auvinen@kuh.fi K. Rilla Á R. Tumelius Á M. Tammi Á J. Viikari Á R. Tammi Department of Anatomy, Institute of Biomedicine, University of Eastern Finland, Kuopio, Finland R. Sironen Á Y. Soini Á V.-M. Kosma Á A. Mannermaa Institute of Clinical Medicine, Pathology and Forensic Medicine, University of Eastern Finland, Kuopio, Finland R. Sironen Á Y. Soini Á V.-M. Kosma Á A. Mannermaa Biocenter Kuopio and Cancer Center of Easter Finland, University of Eastern Finland, Kuopio, Finland R. Sironen Á Y. Soini Á V.-M. Kosma Á A. Mannermaa Imaging Center, Clinical Pathology, Kuopio University Hospital, Kuopio, Finland 123 Breast Cancer Res Treat (2014) 143:277–286 DOI 10.1007/s10549-013-2804-7