MicroRNA signatures and Foxp3+ cell count correlate with relapse occurrence in follicular lymphoma

Noncoding RNAs in B cell non-Hodgkins lymphoma

B-cell non-Hodgkins lymphomas (BCNHLs) are a category of B-cell cancers that show heterogeneity. These blood disorders are derived from different levels of B-cell maturity. Among NHL cases, ∼80-90 % are derived from B-cells. Recent studies have demonstrated that noncoding RNAs (ncRNAs) contribute to almost all parts of mechanisms and are essential in tumorigenesis, including B-cell non-Hodgkins lymphomas. The study of ncRNA dysregulations in B-cell lymphoma unravels important mysteries in lymphoma's molecular etiology. It seems also necessary for discovering novel trials as well as investigating the potential of ncRNAs as markers for their diagnosis and prognosis. In the current study, we summarize the role of ncRNAs involving miRNAs, long noncoding RNAs, as well as circular RNAs in the development or progression of BCNHLs.

Lenalidomide triggers T-cell effector functions in vivo in patients with follicular lymphoma

The immunomodulatory drug lenalidomide is used in patients with follicular lymphoma (FL) with the aim of stimulating T-cell antitumor immune response. However, little is known about the effects of lenalidomide on T-cell biology in vivo in patients with FL. We thus undertook an extensive longitudinal immunologic study, including phenotypic, transcriptomic, and functional analyses, on 44 first-line and 27 relapsed/refractory patients enrolled in the GALEN trial (Obinutuzumab Combined With Lenalidomide for Relapsed or Refractory Follicular B-Cell Lymphoma) to test the efficacy of lenalidomide and obinutuzumab combination in patients with FL. Lenalidomide rapidly and transiently induced an activated T-cell phenotype, including HLA-DR, Tim-3, CD137, and programmed cell death protein 1 (PD-1) upregulation. Furthermore, sequential RNA-sequencing of sorted PD-1+ and PD-1- T-cell subsets revealed that lenalidomide triggered a strong enrichment for several gene signatures related to effector memory T-cell features, including proliferation, antigen receptor signaling, and immune synapse restoration; all were validated at the phenotypic level and with ex vivo functional assays. Correlative analyses pinpointed a negative clinical impact of high effector T-cell and regulatory T-cell percentages before and during treatment. Our findings bring new insight in lenalidomide mechanisms of action at work in vivo and will fuel a new rationale for the design of combination therapies.

The Multifaceted Role and Utility of MicroRNAs in Indolent B-Cell Non-Hodgkin Lymphomas

Normal B-cell development is a tightly regulated complex procedure, the deregulation of which can lead to lymphomagenesis. One common group of blood cancers is the B-cell non-Hodgkin lymphomas (NHLs), which can be categorized according to the proliferation and spread rate of cancer cells into indolent and aggressive ones. The most frequent indolent B-cell NHLs are follicular lymphoma and marginal zone lymphoma. MicroRNAs (miRNAs) are small non-coding RNAs that can greatly influence protein expression. Based on the multiple interactions among miRNAs and their targets, complex networks of gene expression regulation emerge, which normally are essential for proper B-cell development. Multiple miRNAs have been associated with B-cell lymphomas, as the deregulation of these complex networks can lead to such pathological states. The aim of the present review is to summarize the existing information regarding the multifaceted role of miRNAs in indolent B-cell NHLs, affecting the main B-cell subpopulations. We attempt to provide insight into their biological function, the complex miRNA-mRNA interactions, and their biomarker utility in these malignancies. Lastly, we address the limitations that hinder the investigation of the role of miRNAs in these lymphomas and discuss ways that these problems could be overcome in the future.

Systematic review of the potential of MicroRNAs in the management of patients with follicular lymphoma

Follicular lymphoma (FL) is the second most common non-Hodgkin lymphoma and usually presents as an indolent disease. However, some patients present poor outcomes, and FL can transform into more aggressive lymphomas, such as Diffuse Large B cell lymphoma (DLBCL). MicroRNAs (miRNA) are small RNA molecules that participate in posttranscriptional regulation of gene expression, that are emerging biomarkers in cancer. In this systematic review, we included studies evaluating miRNA expression in tumor tissue as diagnosis, transformation or prognosis biomarkers in FL. We identified several miRNAs, which could be diagnostic biomarkers in FL: miR-155-5p and miR-9-3p as miRNAs of potential utility for diagnosis of FL, and miR-150 and miR-17-92 cluster for differential diagnosis between FL and DLBCL. Prognosis and transformation prediction have not been studied in enough depth to draw solid conclusions. Further research is needed to exploit the potential of this field.

Identification of Recurrent Mutations in the microRNA-Binding Sites of B-Cell Lymphoma-Associated Genes in Follicular Lymphoma

Follicular lymphoma (FL) is a common indolent B-cell lymphoma that can transform into the more aggressive transformed FL (tFL). However, the molecular process driving this transformation is uncertain. In this work, we aimed to identify microRNA (miRNA)-binding sites recurrently mutated in follicular lymphoma patients, as well as in transformed FL patients. Using whole-genome sequencing data from FL tumors, we discovered 544 mutations located in bioinformatically predicted microRNA-binding sites. We then studied these specific regions using targeted sequencing in a cohort of 55 FL patients, found 16 recurrent mutations, and identified a further 69 variants. After filtering for QC, we identified 21 genes with mutated miRNA-binding sites that were also enriched for B-cell-associated genes by Gene Ontology. Over 40% of mutations identified in these genes were present exclusively in tFL patients. We validated the predicted miRNA-binding sites of five of the genes by luciferase assay and demonstrated that the identified mutations in BCL2 and EZH2 genes impaired the binding efficiency of miR-5008 and miR-144 and regulated the endogenous levels of messenger RNA (mRNA).

The Interplay between MicroRNAs and the Components of the Tumor Microenvironment in B-Cell Malignancies

An increased focus is being placed on the tumorigenesis and contexture of tumor microenvironment in hematopoietic and solid tumors. Despite recent clinical revolutions in adoptive T-cell transfer approaches and immune checkpoint blockade, tumor microenvironment is a major obstacle to tumor regression in B-cell malignancies. A transcriptional alteration of coding and non-coding RNAs, such as microRNAs (miRNAs), has been widely demonstrated in the tumor microenvironment of B-cell malignancies. MiRNAs have been associated with different clinical-biological forms of B-cell malignancies and involved in the regulation of B lymphocyte development, maturation, and function, including B-cell activation and malignant transformation. Additionally, tumor-secreted extracellular vesicles regulate recipient cell functions in the tumor microenvironment to facilitate metastasis and progression by delivering miRNA contents to neighboring cells. Herein, we focus on the interplay between miRNAs and tumor microenvironment components in the different B-cell malignancies and its impact on diagnosis, proliferation, and involvement in treatment resistance.

MiR-144: A New Possible Therapeutic Target and Diagnostic/Prognostic Tool in Cancers

MicroRNAs (miRNAs) are small and non-coding RNAs that display aberrant expression in the tissue and plasma of cancer patients when tested in comparison to healthy individuals. In past decades, research data proposed that miRNAs could be diagnostic and prognostic biomarkers in cancer patients. It has been confirmed that miRNAs can act either as oncogenes by silencing tumor inhibitors or as tumor suppressors by targeting oncoproteins. MiR-144s are located in the chromosomal region 17q11.2, which is subject to significant damage in many types of cancers. In this review, we assess the involvement of miR-144s in several cancer types by illustrating the possible target genes that are related to each cancer, and we also briefly describe the clinical applications of miR-144s as a diagnostic and prognostic tool in cancers.

Transforming growth factor-β signaling: Tumorigenesis and targeting for cancer therapy

Transforming growth factor (TGF)-β is a multitasking cytokine such that its aberrant expression is related to cancer progression and metastasis. TGF-β is produced by a variety of cells within the tumor microenvironment (TME), and it is responsible for regulation of the activity of cells within this milieu. TGF-β is a main inducer of epithelial-mesenchymal transition (EMT), immune evasion, and metastasis during cancer progression. TGF-β exerts most of its functions by acting on TβRI and TβRII receptors in canonical (Smad-dependent) or noncanonical (Smad-independent) pathways. Members of mitogen-activated protein kinase, phosphatidylinositol 3-kinase/protein kinase B, and nuclear factor κβ are involved in the non-Smad TGF-β pathway. TGF-β acts by complex signaling, and deletion in one of the effectors in this pathway may influence the outcome in a diverse way by taking even an antitumor role. The stage and the type of tumor (contextual cues from cancer cells and/or the TME) and the concentration of TGF-β are other important factors determining the fate of cancer (progression or repression). There are a number of ways for targeting TGF-β signaling in cancer, among them the special focus is on TβRII suppression.

Tumor microenvironment: Interactions and therapy

Tumor microenvironment (TME) is a host for a complex network of heterogeneous stromal cells with overlapping or opposing functions depending on the dominant signals within this milieu. Reciprocal paracrine interactions between cancer cells with cells within the tumor stroma often reshape the TME in favor of the promotion of tumor. These complex interactions require more sophisticated approaches for cancer therapy, and, therefore, advancing knowledge about dominant drivers of cancer within the TME is critical for designing therapeutic schemes. This review will provide knowledge about TME architecture, multiple signaling, and cross communications between cells within this milieu, and its targeting for immunotherapy of cancer.