Paediatric Burkitt lymphoma patient-derived xenografts capture disease characteristics over time and are a model for therapy

A mechanistic insight into cancer progression mediated by Nucleoporins

The nuclear pore complexes are essential for cellular and molecular processes such as trafficking between the cytoplasm and the nucleus, chromatin, transcriptional outputs, and DNA damage repair. Nucleoporins, components of nuclear pore complexes, have been linked to cancer through nucleo-cytoplasmic cargo trafficking, cell division, signalling pathways, chromatin-related processes, and protein stability and degradation. This study aims to understand how nucleoporins specifically contribute to cancer proliferation and progression across various cancer types. Accordingly, angles such as nuclear trafficking, fusion proteins, tumour suppressors, signalling pathways, tumour microenvironment, nucleosomes, and chromatin processes were found to bridge the function of nucleoporins and cancer progression, and the underlying mechanisms have been analysed in this study. A deep understanding of the function of nucleoporins in cancer progression will pave the way for the effective targeting of these molecules for therapeutic gain. Improved treatment responses can enhance the quality of life of cancer patients.

Improving outcomes of childhood and young adult non-Hodgkin lymphoma: 25 years of research and collaboration within the framework of the European Intergroup for Childhood Non-Hodgkin Lymphoma

The European Intergroup for Childhood Non-Hodgkin Lymphoma (EICNHL) was established 25 years ago with the goal to facilitate clinical trials and research collaborations in the field both within Europe and worldwide. Since its inception, much progress has been made whereby major improvements in outcomes have been achieved. In this Review, we describe the different diagnostic entities of non-Hodgkin lymphoma in children and young adults describing key features of each entity and outlining clinical achievements made in the context of the EICNHL framework. Furthermore, we provide an overview of advances in biopathology with an emphasis on the role of biological studies and how they have shaped available treatments. Finally, for each entity, we describe future goals, upcoming clinical trials, and highlight areas of research that require our focus going forward.

Complex genetic and histopathological study of 15 patient-derived xenografts of aggressive lymphomas

Non-Hodgkin lymphomas (NHL) represent the most common hematologic malignancies. Patient-derived xenografts (PDXs) are used for various aspects of translational research including preclinical in vivo validation of experimental treatment approaches. While it was repeatedly demonstrated that PDXs keep majority of somatic mutations with the primary lymphoma samples, from which they were derived, the composition of PDX tumor microenvironment (TME) has not been extensively studied. We carried out a comparative genetic and histopathological study of 15 PDX models derived from patients with various types of NHL including diffuse large B-cell lymphoma (DLBCL; n = 7), Burkitt lymphoma (BL; n = 1), mantle cell lymphoma (MCL; n = 2), and peripheral T-cell lymphomas (PTCL; n = 5). Whole exome sequencing (WES) of the PDXs and primary lymphoma cells was implemented in 13 out of 15 cases with available DNA samples. Standard immunohistochemistry (IHC) was used to analyze the composition of PDX TME. WES data confirmed that PDXs maintained the genetic heterogeneity with the original primary lymphoma cells. In contrast, IHC analysis revealed the following recurrently observed alterations in the composition of PDX tumors: more blastoid lymphoma cell morphology, increased proliferation rate, lack of non-malignant cellular components including T cells and (human or murine) macrophages, and significantly lower intratumoral microvessel density and microvessel area composed of murine vessels. In addition, PDX tumors derived from T-NHL displayed additional differences compared to the primary lymphoma samples including markedly lower desmoplasia (i.e., the extent of both reticular and collagen fibrosis), loss of expression of cytotoxic granules (i.e., perforin, TIA, granzyme B), or loss of expression of T-cell specific antigens (i.e., CD3, CD4, CD8). Our data suggest that despite keeping the same genetic profiles, PDX models of aggressive NHL do not recapitulate the microenvironmental heterogeneity of the original lymphomas. These findings have implications on the relevance of PDX models in the context of preclinical research.

In Vivo and Ex Vivo Patient-Derived Tumor Xenograft Models of Lymphoma for Drug Discovery

In the hemato-oncology field, remarkable scientific progress has been achieved, primarily propelled by the discovery of new technologies, improvement in genomics, and novel in vitro and in vivo models. The establishment of multiple cell line collections and the development of instrumental mouse models enhanced our ability to discover effective therapeutics. However, cancer models that faithfully mimic individual cancers are still imperfect. Patient-derived tumor xenografts (PDTXs) have emerged as a powerful tool for identifying the mechanisms which drive tumorigenesis and for testing potential therapeutic interventions. The recognition that PDTXs can maintain many of the donor samples' properties enabled the development of new strategies for discovering and implementing therapies. Described in this article are protocols for the generation and characterization of lymphoma PDTXs that may be used as the basis of shared procedures. Universal protocols will foster the model utilization, enable the integration of public and private repositories, and aid in the development of shared platforms. © 2021 Wiley Periodicals LLC. Basic Protocol 1: Tissue handling and cryopreservation of primary and PDTX samples Basic Protocol 2: Performing tumor implant in immunocompromised mice PDTX models Alternate Protocol 1: Intra-medullary femoral injection Alternate Protocol 2: Intravenous injection Alternate Protocol 3: Intraperitoneal injection Support Protocol 1: Phenotypical characterization of PDTXs by flow cytometry Support Protocol 2: Biological and molecular characterization of PDTX tumors by PCR detection of IGK, IGH, and TCR rearrangements Basic Protocol 3: Harvesting PDTX-derived tumor cells for ex vivo experiments Basic Protocol 4: In vivo testing of multiple compounds in a PDTX mouse model.

The Role of Autophagy and lncRNAs in the Maintenance of Cancer Stem Cells

Simple Summary

Cancer stem cells (CSCs) represent a distinct cancer subpopulation that can influence the tumour microenvironment, in addition to cancer progression and relapse. A multitude of factors including CSC properties, long noncoding RNAs (lncRNAs), and autophagy play pivotal roles in maintaining CSCs. We discuss the methods of detection of CSCs and how our knowledge of regulatory and cellular processes, and their interaction with the microenvironment, may lead to more effective targeting of these cells. Autophagy and lncRNAs can regulate several cellular functions, thereby promoting stemness factors and CSC properties, hence understanding this triangle and its associated signalling networks can lead to enhanced therapy response, while paving the way for the development of novel therapeutic approaches.

Abstract

Cancer stem cells (CSCs) possess properties such as self-renewal, resistance to apoptotic cues, quiescence, and DNA-damage repair capacity. Moreover, CSCs strongly influence the tumour microenvironment (TME) and may account for cancer progression, recurrence, and relapse. CSCs represent a distinct subpopulation in tumours and the detection, characterisation, and understanding of the regulatory landscape and cellular processes that govern their maintenance may pave the way to improving prognosis, selective targeted therapy, and therapy outcomes. In this review, we have discussed the characteristics of CSCs identified in various cancer types and the role of autophagy and long noncoding RNAs (lncRNAs) in maintaining the homeostasis of CSCs. Further, we have discussed methods to detect CSCs and strategies for treatment and relapse, taking into account the requirement to inhibit CSC growth and survival within the complex backdrop of cellular processes, microenvironmental interactions, and regulatory networks associated with cancer. Finally, we critique the computationally reinforced triangle of factors inclusive of CSC properties, the process of autophagy, and lncRNA and their associated networks with respect to hypoxia, epithelial-to-mesenchymal transition (EMT), and signalling pathways.