Extracting tumor tissue immune status from expression profiles: Correlating renal cancer prognosis with tumor-associated immunome Academic Article uri icon

abstract

  • // Omri Teltsh 1 , Angel Porgador 1, * , Eitan Rubin 1, * 1 The Shraga Segal Department of Microbiology, Immunology, and Genetics, Faculty of Health Sciences, The National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, Beer Sheva, Israel * These authors have contributed equally to this work Correspondence to: Eitan Rubin, e-mail: erubin@bgu.ac.il Angel Porgador, e-mail: angel@bgu.ac.il Keywords: cancer microenvironment, immunome, precision cancer medicine, RNAseq, TCGA Received: June 07, 2015 Accepted: August 28, 2015 Published: September 07, 2015 ABSTRACT Investigating the expression of genes in cancer-associated immune cells (immunome) is imperative for prognosis prediction. However, evaluating the expression of immune-associated genes within cancer biopsy is subject to significant inconsistencies related to the sampling methodology. Here, we present immFocus , a method for extracting immune signals from total RNA sequencing of tumor biopsies, intended for immunity depiction and prognosis evaluation. It is based on reducing the variation which biopsy preparation adds to the apparent expression levels of immune genes. We employed immFocus to normalize gene expression with an immune index using data obtained from renal clear cell carcinoma biopsies. Genes that became less variable due to normalization were found to be preferentially immune-related. Moreover, immune-related genes tended to become more prognostic due to the normalization. These results demonstrate, for the first time, that whole transcriptome sequencing can be used for interrogation of a cancer immunome and for advancing immune-based prognosis.

publication date

  • January 1, 2015