High-Resolution Spatial Proteomics Characterises Colorectal Cancer Consensus Molecular Subtypes.

Background: Identification of the consensus molecular subtypes (CMS) opened significant potential for understanding the tumor biology and intertumoral heterogeneity of colorectal cancer (CRC). However, molecular subtyping in CRC traditionally relies on bulk transcriptomics, therefore, lacks spatial and single-cell level aspect.

Methods: We constructed tissue microarrays using tumor cores from 222 CRC patients.

Anti-seizure effects of JNJ-54175446 in the intra-amygdala kainic acid model of drug-resistant temporal lobe epilepsy in mice.

There remains a need for new drug targets for treatment-resistant temporal lobe epilepsy. The ATP-gated P2X7 receptor coordinates neuroinflammatory responses to tissue injury. Previous studies in mice reported that the P2X7 receptor antagonist JNJ-47965567 suppressed spontaneous seizures in the intraamygdala kainic acid model of epilepsy and reduced attendant gliosis in the hippocampus.

Increased Fusobacterium tumoural abundance affects immunogenicity in mucinous colorectal cancer and may be associated with improved clinical outcome.

There is currently an urgent need to identify factors predictive of immunogenicity in colorectal cancer (CRC). Mucinous CRC is a distinct histological subtype of CRC, associated with a poor response to chemotherapy. Recent evidence suggests the commensal facultative anaerobe Fusobacterium may be especially prevalent in mucinous CRC.

Multiplexed Immunofluorescence Imaging Reveals an Immune-Rich Tumor Microenvironment in Mucinous Rectal Cancer Characterized by Increased Lymphocyte Infiltration and Enhanced Programmed Cell Death Protein 1 Expression.

Background: Mucinous rectal cancer is associated with a higher incidence of microsatellite instability and a poorer response to neoadjuvant chemoradiotherapy compared to other subtypes of rectal adenocarcinoma. Immune checkpoint inhibitors are an emerging family of anticancer therapeutics associated with highly variable outcomes in colorectal cancer. Although the immune landscape of mucinous rectal cancer has not been fully explored, the presence of mucin is thought to act as a barrier preventing immune-cell infiltration.

Bcl-xL Is a Key Mediator of Apoptosis Following KRASG12C Inhibition in KRASG12C-mutant Colorectal Cancer.

Novel covalent inhibitors of KRASG12C have shown limited response rates in patients with KRASG12C-mutant (MT) colorectal cancer. Thus, novel KRASG12C inhibitor combination strategies that can achieve deep and durable responses are needed. Small-molecule KRASG12C inhibitors AZ'1569 and AZ'8037 were used.

Apoptotic and Necroptotic Mediators are Differentially Expressed in Mucinous and Non-Mucinous Colorectal Cancer.

Background: Mucinous colorectal cancer (CRC) represents 10% of all CRC and is associated with chemotherapy resistance. This study aimed to determine expression of apoptosis and necroptosis mediators in mucinous CRC.

Methods: RNA gene expression data were extracted from TCGA.

An atlas of inter- and intra-tumor heterogeneity of apoptosis competency in colorectal cancer tissue at single-cell resolution.

Cancer cells' ability to inhibit apoptosis is key to malignant transformation and limits response to therapy. Here, we performed multiplexed immunofluorescence analysis on tissue microarrays with 373 cores from 168 patients, segmentation of 2.4 million individual cells, and quantification of 18 cell lineage and apoptosis proteins.

Stratification of chemotherapy-treated stage III colorectal cancer patients using multiplexed imaging and single-cell analysis of T-cell populations.

Colorectal cancer (CRC) has one of the highest cancer incidences and mortality rates. In stage III, postoperative chemotherapy benefits <20% of patients, while more than 50% will develop distant metastases. Biomarkers for identification of patients at increased risk of disease recurrence following adjuvant chemotherapy are currently lacking.

Molecular Subtyping Combined with Biological Pathway Analyses to Study Regorafenib Response in Clinically Relevant Mouse Models of Colorectal Cancer.

Purpose: Regorafenib (REG) is approved for the treatment of metastatic colorectal cancer, but has modest survival benefit and associated toxicities. Robust predictive/early response biomarkers to aid patient stratification are outstanding. We have exploited biological pathway analyses in a patient-derived xenograft (PDX) trial to study REG response mechanisms and elucidate putative biomarkers.

BCL(X)L and BCL2 increase the metabolic fitness of breast cancer cells: a single-cell imaging study.

The BCL2 family of proteins regulate apoptosis by controlling mitochondrial outer membrane permeability. However, the effects on mitochondrial structure and bioenergetics have also been reported. Here we comprehensively characterized the effects of BCL2 and BCL(X)L on cellular energetics in MCF7 breast cancer cells using time-lapse confocal single-cell imaging and mitochondrial and cytosolic FRET reporters.

Implementing Systems Modelling and Molecular Imaging to Predict the Efficacy of BCL-2 Inhibition in Colorectal Cancer Patient-Derived Xenograft Models.

Resistance to chemotherapy often results from dysfunctional apoptosis, however multiple proteins with overlapping functions regulate this pathway. We sought to determine whether an extensively validated, deterministic apoptosis systems model, 'DR_MOMP', could be used as a stratification tool for the apoptosis sensitiser and BCL-2 antagonist, ABT-199 in patient-derived xenograft (PDX) models of colorectal cancer (CRC). Through quantitative profiling of BCL-2 family proteins, we identified two PDX models which were predicted by DR_MOMP to be sufficiently sensitive to 5-fluorouracil (5-FU)-based chemotherapy (CRC0344), or less responsive to chemotherapy but sensitised by ABT-199 (CRC0076).

Systems biology analysis identifies molecular determinants of chemotherapy-induced diarrhoea.

Chemotherapy-induced diarrhoea (CID) is a common dose-limiting adverse event in patients with cancer. Here, we hypothesise that chemotherapy evokes apoptosis in normal gut epithelium, contributes to CID and that patients with increased risk of CID can be identified using a systems model of BCL-2 protein interactions (DR_MOMP) that calculates the sensitivity of cells to undergo apoptosis. Normal adjacent gut epithelium tissue was collected during resection surgery from a cohort of 35 patients with stage II-III colorectal cancer (CRC) who were subsequently treated with capecitabine, XELOX or FOLFOX.

Low cleaved caspase-7 levels indicate unfavourable outcome across all breast cancers.

Unlabelled: Elevated levels of the anti-apoptotic BCL2 protein associate with favourable outcome in breast cancer. We investigated whether executioner caspase activation downstream of mitochondrial apoptosis was associated with, or independent, of BCL2's prognostic signature in breast cancer. Levels of pro- and anti-apoptotic BCL2 family proteins were quantified in triple negative breast cancer (TNBC) samples and utilised to calculate BCL2 profiles of 845 breast cancer patients.

Systems modeling accurately predicts responses to genotoxic agents and their synergism with BCL-2 inhibitors in triple negative breast cancer cells.

Triple negative breast cancer (TNBC) is an aggressive form of breast cancer which accounts for 15-20% of this disease and is currently treated with genotoxic chemotherapy. The BCL2 (B-cell lymphoma 2) family of proteins controls the process of mitochondrial outer membrane permeabilization (MOMP), which is required for the activation of the mitochondrial apoptosis pathway in response to genotoxic agents. We previously developed a deterministic systems model of BCL2 protein interactions, DR_MOMP that calculates the sensitivity of cells to undergo mitochondrial apoptosis.

BCL-2 system analysis identifies high-risk colorectal cancer patients.

Objective: The mitochondrial apoptosis pathway is controlled by an interaction of multiple BCL-2 family proteins, and plays a key role in tumour progression and therapy responses. We assessed the prognostic potential of an experimentally validated, mathematical model of BCL-2 protein interactions (DR_MOMP) in patients with stage III colorectal cancer (CRC).

Design: Absolute protein levels of BCL-2 family proteins were determined in primary CRC tumours collected from n=128 resected and chemotherapy-treated patients with stage III CRC.

A Stepwise Integrated Approach to Personalized Risk Predictions in Stage III Colorectal Cancer.

Apoptosis is essential for chemotherapy responses. In this discovery and validation study, we evaluated the suitability of a mathematical model of apoptosis execution (APOPTO-CELL) as a stand-alone signature and as a constituent of further refined prognostic stratification tools. Apoptosis competency of primary tumor samples from patients with stage III colorectal cancer ( = 120) was calculated by APOPTO-CELL from measured protein concentrations of Procaspase-3, Procaspase-9, SMAC, and XIAP.

Calnexin, an ER stress-induced protein, is a prognostic marker and potential therapeutic target in colorectal cancer.

Background: Colorectal cancer (CRC) is a leading cause of cancer mortality in the Western world and commonly treated with genotoxic chemotherapy. Stress in the endoplasmic reticulum (ER) was implicated to contribute to chemotherapeutic resistance. Hence, ER stress related protein may be of prognostic or therapeutic significance.

The indirect activation model of mitochondrial outer membrane permeabilisation (MOMP) initiation requires a trade-off between robustness in the absence of and sensitivity in the presence of stress.

Mitochondrial outer membrane permeabilisation (MOMP) is a hallmark of apoptosis and is controlled by antagonising members of the BCL 2 protein family. However, whether the effector proteins for MOMP, BAX and BAK, require a separate activation step (direct activation model) or if the sole inhibition of otherwise active effectors by anti-apoptotic BCL 2 proteins suffices (indirect activation model) is controversial. To address this question, we recently identified that, in most cells, effector proteins were more abundant than their inhibitors.

Systems analysis of BCL2 protein family interactions establishes a model to predict responses to chemotherapy.

Apoptotic desensitization is a hallmark of cancer cells, but present knowledge of molecular systems controlling apoptosis has yet to provide significant prognostic insights. Here, we report findings from a systems study of the intrinsic pathway of apoptosis by BCL2 family proteins and clinical translation of its findings into a model with applications in colorectal cancer (CRC). By determining absolute protein quantifications in CRC cells and patient tumor samples, we found that BAK and BAX were expressed more highly than their antiapoptotic inhibitors.

Systems analysis of cancer cell heterogeneity in caspase-dependent apoptosis subsequent to mitochondrial outer membrane permeabilization.

Deregulation of apoptosis is a hallmark of carcinogenesis. We here combine live cell imaging and systems modeling to investigate caspase-dependent apoptosis execution subsequent to mitochondrial outer membrane permeabilization (MOMP) in several cancer cell lines. We demonstrate that, although most cell lines that underwent MOMP also showed robust and fast activation of executioner caspases and apoptosis, the colorectal cancer cell lines LoVo and HCT-116 Smac(-/-), similar to X-linked inhibitor of apoptosis protein (XIAP)-overexpressing HeLa (HeLa XIAP(Adv)) cells, only showed delayed and often no caspase activation, suggesting apoptosis impairment subsequent to MOMP.