Title: Analyses of Tumour Infiltrating Lymphocytes in lethal Prostate Cancer: a biomarker analysis in the multi-centre STAMPEDE clinical trial
Funder: Cancer Research UK

Abstract: Our preliminary data shows some prostate cancers (PC) have a high Tumour Infiltrating Lymphocyte (TIL) score. We propose to dissect T cell phenotypic subtypes using a CD8|CD4|FOXP3 triple immunohistochemistry assay and test associations with pathological variables, clinical end-points and genomic and transcriptomic subtypes in a subset of 350 patients. These data will support further study of the immune micro-environment across the whole cohort. HYPOTHESES: - Integration of TIL phenotypes with proliferation indices will refine outcome prediction and will identify differences in treatment sensitivities with abiraterone or docetaxel. - TIL biomarker profiling of PC will identify patients enriched for response to dual immune check-point blockade and allow use of such therapies at start of androgen deprivation therapy. AIMS: This project aims to use multiplex immunohistochemistry (IHC) and digital image-analysis to generate preliminary data on the tumour inflammatory environment in a cohort of men with high-risk or metastatic PC. We aim to implement digital image analysis for detection and chromogenic-based annotations to determine the relevance of spatial arrangements between the neoplastic and inflammatory components: - To work with computer scientists to train, using computational cell-by-cell comparison to pathologist scoring of immune infiltrate, and then validate an image analysis algorithm that will be used for biomarker selection for future City of London biological therapy clinical trials in PC; - Determine which combinations of infiltrate associate with clinically relevant outcomes. PROPOSED METHODOLOGY: Subjects: Samples (diagnostic trans-rectal biopsies) from 350 patients with metastatic/locally advanced PC from the STAMPEDE trial, randomly selected and matching the ITT population. Instruments: - Histologic evaluation: Central review of H&Es and Gleason Scoring –Berney, QMUL. Proliferation index assessment: Immunohistochemistry for Ki-67 in matched samples (already stained) - Berney, Mendes, Parker. - Immunophenotyping: CD8|CD4|FOXP3 triple immunohistochemistry assay – Marafioti, Linch, Powles. - Whole slide scanning – QMUL and UCL. - Image analysis performed with customised algorithms using VISIOPHARM software – UCL, Birmingham. - Use of the computational and modelling core to support analysis of the data generated from digitized slides. This includes data extraction and color deconvolution, pixel distribution, texture analyses, and spatial cross-correlation analysis. All. - Association with outcomes in this pilot set will be tested with the MRC CTU @UCL (Brown): PFS, MFS, OS. - Integration of TIL phenotypes with whole genome copy number profiling and whole transcriptome analysis being generated separately on the same tumour samples will also be performed – Attard, Powles, Mendes, Parker


Research activity codes: 4.1 DISCOVERY AND PRECLINICAL TESTING OF MARKERS AND TECHNOLOGIES;4.2 EVALUATION OF MARKERS AND TECHNOLOGIES
Health categories: CANCER AND NEOPLASMS