Search

We propose a comprehensive approach to oncological disease, based on a systemic consideration of biology, health and disease. Our two previous review articles focused on tumour microenvironment and the discovery of new biomarkers; here we discuss the practical application of these principles to pathology, through the identification, evaluation and quantitative analysis of new prognostic and predictive factors (Immunoscore, TIME). We also consider the clinical use of promising, better tolerated treatments, such as immunotherapy. The integrative pathologist now has access to the latest improved oncology stratification tools designed to identify effective treatment strategies, based on the natural evolution of clinical and scientific knowledge that transcend the gene-centric theory of cancer.

Cancer cells all share the feature of being immersed in a complex environment with altered cell-cell/cell-extracellular element communication, physicochemical information, and tissue functions. The so-called tumour microenvironment (TME) is becoming recognised as a key factor in the genesis, progression and treatment of cancer lesions. Beyond genetic mutations, the existence of a malignant microenvironment forms the basis for a new perspective in cancer biology where connections at the system level are fundamental. From this standpoint, different aspects of tumour lesions such as morphology, aggressiveness, prognosis and treatment response can be considered under an integrated vision, giving rise to a new field of study and clinical management. Nowadays, somatic mutation theory is complemented with study of TME components such as the extracellular matrix, immune compartment, stromal cells, metabolism and biophysical forces. In this review we examine recent studies in this area and complement them with our own research data to propose a classification of stromal changes. Exploring these avenues and gaining insight into malignant phenotype remodelling, could reveal better ways to characterize this disease and its potential treatment.

BCL2 family proteins are important regulators of mitochondrial outer membrane permeabilization (MOMP). In recent years, BCL2 family proteins have also been linked to the regulation of mitochondrial bioenergetics and dynamics. Given their overexpression in breast cancer cells, we sought to explore whether two key members of this family, BCL2 and BCL(X)L impacted on mitochondrial fusion/fission processes. By employing a single cell imaging and RNA sequencing we found that overexpression of BCL2 or BCL(X)L increases mitochondrial dynamics and alters the expression profile of genes involved in this process. Collectively, our data show that overexpression of BCL2 proteins regulates mitochondrial dynamics in breast cancer tumor cells.

Liver fibrosis (LF) occurs as a result of persistent liver injury and can be defined as a pathologic, chronic, wound-healing process in which functional parenchyma is progressively replaced by fibrotic tissue. As a phenomenon involved in the majority of chronic liver diseases, and therefore prevalent, it exerts a significant impact on public health. This impact becomes even more patent given the lack of a specific pharmacological therapy, with LF only being ameliorated or prevented through the use of agents that alleviate the underlying causes. Hepatic stellate cells (HSCs) are fundamental mediators of LF, which, activated in response to pro-fibrotic stimuli, transdifferentiate from a quiescent phenotype into myofibroblasts that deposit large amounts of fibrotic tissue and mediate pro-inflammatory effects. In recent years, much effort has been devoted to understanding the mechanisms through which HSCs are activated or inactivated. Using cell culture and/or different animal models, numerous studies have shown that autophagy is enhanced during the fibrogenic process and have provided specific evidence to pinpoint the fundamental role of autophagy in HSC activation. This effect involves - though may not be limited to - the autophagic degradation of lipid droplets. Several hepatoprotective agents have been shown to reverse the autophagic alteration present in LF, but clinical confirmation of these effects is pending. On the other hand, there is evidence that implicates autophagy in several anti-fibrotic mechanisms in HSCs that stimulate HSC cell cycle arrest and cell death or prevent the generation of pro-fibrotic mediators, including excess collagen accumulation. The objective of this review is to offer a comprehensive analysis of published evidence of the role of autophagy in HSC activation and to provide hints for possible therapeutic targets for the treatment and/or prevention of LF related to autophagy. © 2021 The Authors. The Journal of Pathology published by John Wiley & Sons, Ltd. on behalf of The Pathological Society of Great Britain and Ireland.

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. We found that BCL2 and BCL(X)L increase the metabolic robustness of MCF7 cells, and that this was associated with increased mitochondrial NAD(P)H and ATP levels. Experiments with the F1F0 synthase inhibitor oligomycin demonstrated that BCL2 and in particular BCL(X)L, while not affecting ATP synthase activity, more efficiently coupled the mitochondrial proton motive force with ATP production. This metabolic advantage was associated with an increased resistance to nutrient deprivation and enhanced clonogenic survival in response to metabolic stress, in the absence of profound effects on cell death. Our data suggest that a primary function of BCL(X)L and BCL2 overexpression in tumor cells is to increase their resistance to metabolic stress in the tumor microenvironment, independent of cell death signaling. ispartof: CELL DEATH AND DIFFERENTIATION vol:28 issue:5 pages:1512-1531 ispartof: location:England status: published

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, &lsquo, DR_MOMP&rsquo, 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). Treatment with ABT-199 significantly improved responses of CRC0076 PDXs to 5-FU-based chemotherapy, but showed no sensitisation in CRC0344 PDXs, as predicted from systems modelling. 18F-Fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG-PET/CT) scans were performed to investigate possible early biomarkers of response. In CRC0076, a significant post-treatment decrease in mean standard uptake value was indeed evident only in the combination treatment group. Radiomic CT feature analysis of pre-treatment images in CRC0076 and CRC0344 PDXs identified features which could phenotypically discriminate between models, but were not predictive of treatment responses. Collectively our data indicate that systems modelling may identify metastatic (m)CRC patients benefitting from ABT-199, and that 18F-FDG-PET could independently support such predictions.

© 2020 by the authors., Tumor progression is mediated by reciprocal interaction between tumor cells and their surrounding tumor microenvironment (TME), which among other factors encompasses the extracellular milieu, immune cells, fibroblasts, and the vascular system. However, the complexity of cancer goes beyond the local interaction of tumor cells with their microenvironment. We are on the path to understanding cancer from a systemic viewpoint where the host macroenvironment also plays a crucial role in determining tumor progression. Indeed, growing evidence is emerging on the impact of the gut microbiota, metabolism, biomechanics, and the neuroimmunological axis on cancer. Thus, external factors capable of influencing the entire body system, such as emotional stress, surgery, or psychosocial factors, must be taken into consideration for enhanced management and treatment of cancer patients. In this article, we review prognostic and predictive biomarkers, as well as their potential evaluation and quantitative analysis. Our overarching aim is to open up new fields of study and intervention possibilities, within the framework of an integral vision of cancer as a functional tissue with the capacity to respond to different non-cytotoxic factors, hormonal, immunological, and mechanical forces, and others inducing stroma and tumor reprogramming., This work was supported by grants from ISCIII (FIS) and FEDER (European Regional Development Fund) PI17/01558; CIBERONC (contract CB16/12/00484); Fundación Científica de la Asociación Española contra el Cáncer (FAECC2015/006) and NEN Association (Nico contra el cancer infantil 2017—PVR00157).

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. Biomarkers including single apoptosis proteins and network-enriched apoptosis system signatures were evaluated using uni- and multi-variate Cox-models. In both TNBC and non-TNBC breast cancer, the anti-apoptotic BCL2 protein was particularly abundant when compared to other solid tumours. High BCL2 protein levels were prognostic of favourable outcome across all breast cancers (HR 0.4, 95% CI 0.2-0.6, Wald p 0.0001). Although BCL2 and cleaved caspase-7 levels were negatively correlated, levels of cleaved caspase-7 were also associated with favourable outcome (HR 0.4, 95% CI 0.3-0.7, Wald p = 0.001). A combination of low BCL2 and low cleaved caspase-7 protein levels was highly prognostic of unfavourable outcome across all breast cancers (HR 11.29, 95% CI 2.20-58.23, Wald p = 0.01). A combination of BCL2 and cleaved caspase-7 levels is a promising prognostic biomarker in breast cancer patients.BCL2 levels are elevated in breast cancer where they are marker of good prognosis. BCL2 and active caspase levels correlate negatively; yet, active caspases indicate good outcome. Low BCL2 and low caspase-7 are highly prognostic of unfavourable outcome across all breast cancers. BCL2 levels indicate molecular subtype and tumour proliferation status in breast cancer.

Background: Apoptosis signalling is controlled by a complex interaction of pro- and anti-apoptotic BCL2 proteins and its dysregulation is believed to be a major contributor to therapy responses and resistance in cancer. We previously demonstrated that inhibition of cell death in cancer cell is associated to poor outcome in colorectal cancer (Lindner et al., Cancer Res, 2012) and to lower cell death in triple negative breast cancer (TNBC) cells in vitro (Lucantoni et al., in review). In ER+ breast cancer, the anti-apoptotic protein BCL2 is commonly overexpressed, but its expression is associated with improved clinical outcome. The aim of this study was to assess whether system modelling of BCL2 protein interactions stratifies low- and high-risk breast cancer patients, and to determine the contribution of apoptosis signalling in different molecular subtypes of breast cancer. Methods: Protein levels of BAK, BAX, BCL2 and BCL(X) were determined in fresh frozen, TNBC samples from the BREAST-PREDICT Irish Cancer Society Collaborative Research Centre cohort, using HeLa cells as standard in which absolute protein levels were previously determined. Clinical, protein level and gene expression datasets of 845 invasive breast carcinoma patients were accessed from The Cancer Genome Atlas project, and BCL2 protein profiles were calculated by linear regression based on the BREAST-PREDICT cohort. In both cohorts, profiles were used to calculate the stress dose required to induce mitochondrial apoptosis (η). Results: In contrast to experiments with TNBC cells in which a high η indicated lower rates of cell death in vitro (Lucantoni et al., in review), we found that in breast cancer patients, η ≤ 0 was associated with lower overall survival (OS) compare to η > 0 (HR 2.1, 95%CI 1.3-3.3, p < 0.01). η > 0 was associated with lower levels of cleaved caspase 7 compared to η ≤ 0 (ANOVA & Tukey post-hoc; p < 0.1). Cleaved caspase 7 levels > mean were associated with improved OS compared to levels ≤ mean (HR 0.4, 95%CI 0.3-0.7, p = 0.001). High values of η were significantly associated with lower proliferation in ER/PR+ cancer (ANOVA & Tukey post-hoc; p < 0.01), but not in HER2+ or TNBC. Next we performed hierarchical cluster analysis (ConsensusClusterPlus; Monti et al, Machine Learning, 2003) with 61 additional mRNAs and proteins which are not implemented in our systems modelling approach. We found a subgroup with high BAD, PUMA, BOK and TRADD mRNA expression levels in ER/PR+ breast cancer patients, independently of the value of η. ER/PR+, but not HER2+ or TNBC, patients with an averaged expression of these 4 mRNA > mean had significant higher OS compared with patients with an averaged expression ≤ mean (HR 0.4, 95%CI 0.2-0.9, p = 0.02). Conclusions: Impairment of apoptosis assessed solely on the levels of BAK, BAX, BCL2 and BCLX(L) proteins were not sufficient as prognostic marker in breast cancer patients. However, our analysis suggest that patients with ER/PR+ cancer cells potentially 'primed' towards apoptosis - via the expression of pro-apoptotic BAD, PUMA, BOK and TRADD - had a more favourable clinical outcome compared to patients with cancer cells lacking this priming. Citation Format: Lindner AU, Lucantoni F, Vareslija D, Resler A, Gallagher WM, Hill A, Young L, Prehn JHM. High expression of BAD, PUMA, BOK and TRADD mRNA is associated with higher overall survival in ER+ and PR+ breast cancer patients [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P5-10-02.

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. Here we determined whether DR_MOMP predicts responses of TNBC cells to genotoxic agents and the re-sensitization of resistant cells by BCL2 inhibitors. Using absolute protein levels of BAX, BAK, BCL2, BCL(X)L and MCL1 as input for DR_MOMP, we found a strong correlation between model predictions and responses of a panel of TNBC cells to 24 and 48 h cisplatin (R2 = 0.96 and 0.95, respectively) and paclitaxel treatments (R2 = 0.94 and 0.95, respectively). This outperformed single protein correlations (best performer BCL(X)L with R2 of 0.69 and 0.50 for cisplatin and paclitaxel treatments, respectively) and BCL2 proteins ratio (R2 of 0.50 for cisplatin and 0.49 for paclitaxel). Next we performed synergy studies using the BCL2 selective antagonist Venetoclax /ABT199, the BCL(X)L selective antagonist WEHI-539, or the MCL1 selective antagonist A-1210477 in combination with cisplatin. In silico predictions by DR_MOMP revealed substantial differences in treatment responses of BCL(X)L, BCL2 or MCL1 inhibitors combinations with cisplatin that were successfully validated in cell lines. Our findings provide evidence that DR_MOMP predicts responses of TNBC cells to genotoxic therapy, and can aid in the choice of the optimal BCL2 protein antagonist for combination treatments of resistant cells.

In this chapter, we describe the unique properties of the mitochondrial intermembrane space (IMS) and its role in apoptosis signalling. We delineate the current models of mitochondrial outer membrane permeabilization (MOMP) during apoptosis and highlight the role of single cell imaging studies in understanding the kinetics of this process. Finally, we will discuss the individual IMS proteins that are released during MOMP and their respective role in the initiation of caspase-dependent and caspase-independent apoptosis.