AURKA is a prognostic biomarker for good overall survival in stage II colorectal cancer patients

Abstract

BackgroundCancer prevention has augmented the proportion of early stage colorectal cancer (CRC) diagnoses. Especially UICC stage II CRC is in urgent need for a better patient stratification to improve clinical and therapeutic decision making. We analyzed the prognostic value of AURKA expression in stage II CRC patients. By using a scoring system based on staining intensity and frequency, we addressed the association of AURKA with patient survival and clinically relevant molecular markers. MethodsA study cohort of 208 CRC patients (UICC stage II) was assembled. A combined measure of expression frequency and staining intensity of AURKA (H-Score) was analyzed via immunohistochemistry, and the clinical performance of this variable was studied. Association of AURKA with mutant KRAS and abundance of nuclear β-catenin as a surrogate marker of Wnt activity was examined. Time-dependent ROC analysis revealed the prognostic performance of AURKA at different patient follow-up times. ResultsThe AURKA H-Score correlated with good overall survival (log-rank test, p-value <0.05) and wild-type KRAS (p-value <0.01). Time-dependent ROC analysis revealed a discriminative ability of the AURKA H-Score regarding overall survival between 5 and 12 years of patient follow-up (AUC: 0.570–0.595). There was no correlation of the AURKA H-Score with disease recurrence or nuclear β-catenin abundance. ConclusionBy applying universally applicable immunohistochemistry, we propose that the AURKA H-Score, which is a combined measure of staining intensity and frequency of positively staining tumor cells, correlates with good overall survival and a wild-type KRAS status in UICC stage II CRC.