PT - JOURNAL ARTICLE AU - Sarah Kammerer AU - Stephan Wenzel Jahn AU - Elke Winter AU - Sylvia Eidenhammer AU - Simin Rezania AU - Peter Regitnig AU - Martin Pichler AU - Wolfgang Schreibmayer AU - Thomas Bauernhofer TI - Critical evaluation of <em>KCNJ3</em> gene product detection in human breast cancer: mRNA in situ hybridisation is superior to immunohistochemistry AID - 10.1136/jclinpath-2016-203798 DP - 2016 Dec 01 TA - Journal of Clinical Pathology PG - 1116--1121 VI - 69 IP - 12 4099 - http://jcp.bmj.com/content/69/12/1116.short 4100 - http://jcp.bmj.com/content/69/12/1116.full SO - J Clin Pathol2016 Dec 01; 69 AB - Increased expression levels of KCNJ3 have been correlated with lymph node metastases and poor prognosis in patients with breast cancer, suggesting a prognostic role of KCNJ3. We aimed to establish protocols for the detection of KCNJ3 in formalin-fixed, paraffin-embedded (FFPE) breast cancer tissue. Several antibodies were tested for sensitivity and specificity by western blot, followed by optimisation of the immunohistochemistry (IHC) procedure and establishment of KCNJ3 mRNA in situ hybridisation (ISH). Methods were validated by processing 15 FFPE breast cancer samples for which microarray data were available. Spearman's rank correlation analysis resulted in borderline significant correlation for IHC versus ISH (rS: 0.625; p&lt;0.05) and IHC versus microarray (rS: 0.668; p&lt;0.01), but in significant correlation for ISH versus microarray (rS: 0.861; p&lt;0.001). The ISH method was superior to IHC, regarding robustness, sensitivity and specificity and will aid to further study expression levels of KCNJ3 in both malignant and physiological conditions.