miRNAs are promising biomarkers in oncology as their small size makes them less susceptible to degradation than mRNA in FFPE tissue. We aimed to derive a hypoxia-associated miRNA signature for bladder cancer.
Taqman miRNA array cards identified miRNA seed genes induced under hypoxia in bladder cancer cell lines. A signature was derived using feature selection methods in a TCGA BLCA training data set. miRNA expression data were generated for 190 tumours from the BCON Phase 3 trial and used for independent validation.
A 14-miRNA hypoxia signature was derived, which was prognostic for poorer overall survival in the TCGA BLCA cohort (n = 403, p = 0.001). Univariable analysis showed that the miRNA signature predicted an overall survival benefit from having carbogen-nicotinamide with radiotherapy (HR = 0.30, 95% CI 0.094-0.95, p = 0.030) and performed similarly to a 24-gene mRNA signature (HR = 0.47, 95% CI 0.24-0.92, p = 0.025). Combining the signatures improved performance (HR = 0.26, 95% CI 0.08-0.82, p = 0.014) with borderline significance for an interaction test (p = 0.065). The interaction test was significant for local relapse-free survival LRFS (p = 0.033).
A 14-miRNA hypoxia signature can be used with an mRNA hypoxia signature to identify bladder cancer patients benefitting most from having carbogen and nicotinamide with radiotherapy.
British journal of cancer. 2021 Apr 12 [Epub ahead of print]
Mairah T Khan, Joely J Irlam-Jones, Ronnie Rodrigues Pereira, Brian Lane, Helen R Valentine, Kai Aragaki, Lars Dyrskjøt, David J McConkey, Peter J Hoskin, Ananya Choudhury, Catharine M L West
Translational Radiobiology Group, Division of Cancer Sciences, University of Manchester, Manchester Academic Health Science Centre, Christie NHS Foundation Trust Hospital, Manchester, UK., Translational Oncogenomics, Cancer Research UK Manchester Institute, Oglesby Cancer Research Building, University of Manchester, Manchester, UK., Greenberg Bladder Cancer Institute, Johns Hopkins University, Baltimore, MD, USA., Department of Molecular Medicine, Aarhus University Hospital, Aarhus, Denmark., Translational Radiobiology Group, Division of Cancer Sciences, University of Manchester, Manchester Academic Health Science Centre, Christie NHS Foundation Trust Hospital, Manchester, UK. .