Digital analysis and epigenetic regulation of the signature of rejection in colorectal cancer

Abstract

The immune system plays a pivotal role in the development and progression of colorectal cancer (CRC). Tumor immune rejection has been previously linked to the activation of the interferon-stimulated genes (ISG) STAT1, IRF-5 and IRF-1. Specific immunoregulatory microRNAs (miRNAs) may impact the expression of these ISG in the tumor microenvironment. In this translational study, we develop a digital image analysis protocol to identify the ISG-gene expression signature and investigate miRNA expression in the immediate environment of invading cancer cells. Digital immunophenotyping was performed using next generation tissue microarrays from 241 well-characterized CRC patients and analyzed with clinicopathological and molecular information. Active ISG signaling in the tumor stroma differentiated an immune-activated (n = 178) and a quiescent (n = 43) phenotype. The activated phenotype was associated with high counts of intratumoral CD8 cytotoxic T-lymphocytes (CTL; = 0.007) and expression of the immune effector molecules granzyme B ( < 0.001) and perforin ( = 0.020). Immune-activated tumors also showed an elevated expression of the intercellular adhesion molecule-1 (ICAM-1, = 0.006) which may facilitate CTL infiltration. Patients with immune-activated CRC had a considerably reduced risk of developing distant metastases ( = 0.001, OR = 0.034, 95%CI = 0.006-0.183). High expression of the immunoregulatory miR-34a and miR-93 corresponded to a 2-2.5-fold decrease of STAT1 ( = 0.006) and IRF-1 ( = 0.058), a feature more commonly seen in a quiescent microenvironment. Analysis of a combined ISG marker profile by digital pathology stratifies CRC patients into diametrically opposed immune phenotypes. Targeted inhibition of miRNAs within the tumor microenvironment may form a new strategy to stimulate the anti-tumoral immune response.

Precision immunoprofiling by image analysis and artificial intelligence

“…Virtual multistaining also offers the unique opportunity of combining distinct histological methods, such as RNA in situ hybridization and IHC for multiparametric tissue profiling. This approach has been recently used to spatially correlate the expression of specific microRNAs, interferon-stimulated target genes, T cell infiltration, and the expression of cytotoxic effector molecules in the microenvironment of CRC [ 45 ]. Limitations include the requirement for multiple tissue sections, inevitable sectioning artifacts, and the need to perform complex image transformation procedures for precise image alignment.…”

Clinical Significance of a Novel Tumor Progression-Associated Immune Signature in Colorectal Adenocarcinoma

“…Granzyme B ( GZMB ) (HR = 0.742, P < 0.001), whose encoded preproprotein is secreted by natural killer cells and cytotoxic T-lymphocytes, also acted as an independent protective factor for the prognosis of patients with CRC. Koelzer et al (2017) found that the immune-activated phenotype was associated with high counts of intratumoral CD8 cytotoxic T-lymphocytes ( P = 0.007) and the expression of the immune effector molecule GZMB ( P < 0.001). The increased infiltration of cytotoxic T-lymphocytes is the key to tumor immune rejection.…”

Identification of Lactate-Related Gene Signature for Prediction of Progression and Immunotherapeutic Response in Skin Cutaneous Melanoma

“…A previous study demonstrates that the PD-L1 status in the tumor is a biomarker that reflects the response or resistance to ICIs, which was consistent with our conclusion ( 66 ). Furthermore, some comprehensive studies have revealed a mechanistically meaningful role of targeting TME, evidenced by the positive association of the ‘T-cell-inflamed tumor microenvironment’ with the effectiveness of diverse immune treatment ( 67 – 69 ).…”