•Anti-PD-1 in HL is very effective, but complete responses are scarce.•Efficiency of anti-PD-1 might involve T cells, NK cells and macrophages.•Anti-PD-1 resistance can involve loss of HLA or an ...increase in Tregs.•Anti-PD-1 resistance can involve suppression of T cell functionality.
Hodgkin lymphoma is a B cell derived malignancy characterized by a low number of tumor cells within an environment consisting of inflammatory cells. Recently, immune checkpoint blockade targeting the PD-1-PD-L1 axis has shown to be a great success in relapsed and refractory Hodgkin lymphoma patients. However, complete responses are scarce and median progression-free survival is limited to around 11–15 months. Efficiency of PD-1 blockade in HL might be dependent on CD4+ T cells, but also tumor associated macrophages (TAMs) and NK cells are implicated. The aim of this review is to highlight currently known prominent immune evasion strategies and discuss their possible contribution to primary or acquired resistance to immune checkpoint blockade in Hodgkin lymphoma. These include T cell dependent mechanisms such as shaping of the inflammatory infiltrate, lack of presentation of antigens and neoantigens and production of molecules involved in suppression of T cell functionality such as other immune checkpoints, indoleamine 2,3-dioxygenase and adenosine. Moreover, the role of NK cells and TAMs in efficient PD-1 blockade will be discussed. Targeting these mechanisms in parallel to PD-1 may potentially increase efficiency of PD-1 blockade therapy.
Flat epithelial atypia (FEA) of the breast is characterised by a few layers of mildly atypical luminal epithelial cells. Genetic changes found in ductal carcinoma in situ (DCIS) and invasive ductal ...breast cancer (IDC) are also found in FEA, albeit at a lower concentration. So far, miRNA expression changes associated with invasive breast cancer, like miR-21, have not been studied in FEA.
We performed miRNA in-situ hybridization (ISH) on 15 cases with simultaneous presence of normal breast tissue, FEA and/or DCIS and 17 additional cases with IDC. Expression of the miR-21 targets PDCD4, TM1 and PTEN was investigated by immunohistochemistry.
Two out of fifteen cases showed positive staining for miR-21 in normal breast ductal epithelium, seven out of fifteen cases were positive in the FEA component and nine out of twelve cases were positive in the DCIS component. A positive staining of miR-21 was observed in 15 of 17 IDC cases. In 12 cases all three components were present in one tissue block and an increase of miR-21 from normal breast to FEA and to DCIS was observed in five cases. In three cases the FEA component was negative, whereas the DCIS component was positive for miR-21. In three other cases, normal, FEA and DCIS components were negative for miR-21 and in the last case all three components were positive. Overall we observed a gradual increase in percentage of miR-21 positive cases from normal, to FEA, DCIS and IDC. Immunohistochemical staining for PTEN revealed no obvious changes in staining intensities in normal, FEA, DCIS and IDC. Cytoplasmic staining of PDCD4 increased from normal to IDC, whereas, the nuclear staining decreased. TM1 staining decreased from positive in normal breast to negative in most DCIS and IDC cases. In FEA, the staining pattern for TM1 was similar to normal breast tissue.
Upregulation of miR-21 from normal ductal epithelial cells of the breast to FEA, DCIS and IDC parallels morphologically defined carcinogenesis. No clear relation was observed between the staining pattern of miR-21 and its previously reported target genes.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Nodular lymphocyte predominant Hodgkin lymphoma (NLPHL) is characterized by a low percentage of neoplastic lymphocyte predominant (LP) cells in a background of lymphocytes. The goal of this study is ...to characterize the microenvironment in NLPHL. Ten NLPHL cases and seven reactive lymph nodes (RLN) were analyzed by flow cytometry for the main immune cells and multiple specific subpopulations. To discriminate between cells in or outside the tumor cell area, we used CD26. We observed significantly lower levels of CD20+ B-cells and CD56+ NK cells and higher levels of CD4+ T-cells in NLPHL in comparison to RLN. In the subpopulations, we observed increased numbers of PD-1+CD4+ T follicular helper cells (TFH), CD69+CD4+ and CD69+CD8+ T-cells and CCR7-CD45RA-CD4+ effector memory T-cells, while FoxP3+CD4+ T regulatory cells (Tregs) and CCR7-CD45RA+ terminally differentiated CD4+ T-cells were decreased in NLPHL compared to RLN. CD69+ cells were increased in the tumor cell area in CD4+ and CD8+ T-cells, while FoxP3+CD25+CD4+ Tregs and CD25+CD8+ T-cells were significantly increased outside the tumor area. Thus, we show a markedly altered microenvironment in NLPHL, with lower numbers of NK cells and Tregs. PD-1+CD4+ and CD69+ T-cells were located inside, and Tregs and CD25+CD8+ cells outside the tumor cell area.
Summary
MicroRNAs (miRNAs) are instrumental to many aspects of immunity, including various levels of T‐cell immunity. Over the last decade, crucial immune functions were shown to be regulated by ...specific miRNAs. These ‘immuno‐miRs’ regulate generic cell biological processes in T cells, such as proliferation and apoptosis, as well as a number of T‐cell‐specific features that are fundamental to the development, differentiation and function of T cells. In this review, we give an overview of the current literature with respect to the role of miRNAs at various stages of T‐cell development, maturation, differentiation, activation and ageing. Little is known about the involvement of miRNAs in thymic T‐cell development, although miR‐181a and miR‐150 have been implicated herein. In contrast, several broadly expressed miRNAs including miR‐21, miR‐155 and miR‐17~92, have now been shown to regulate T‐cell activation. Other miRNAs, including miR‐146a, show a more T‐cell‐subset‐specific expression pattern and are involved in the regulation of processes unique to that specific T‐cell subset. Importantly, differences in the miRNA target gene repertoires of different T‐cell subsets allow similar miRNAs to control different T‐cell‐subset‐specific functions. Interestingly, several of the here described immuno‐miRs have also been implicated in T‐cell ageing and there are clear indications for causal involvement of miRNAs in immunosenescence. It is concluded that immuno‐miRs have a dynamic regulatory role in many aspects of T‐cell differentiation, activation, function and ageing. An important notion when studying miRNAs in relation to T‐cell biology is that specific immuno‐miRs may have quite unrelated functions in closely related T‐cell subsets.
Cigarette smoking causes lung inflammation and tissue damage. Lung fibroblasts play a major role in tissue repair. Previous studies have reported smoking-associated changes in fibroblast responses ...and methylation patterns. Our aim was to identify the effect of current smoking on miRNA expression in primary lung fibroblasts. Small RNA sequencing was performed on lung fibroblasts from nine current and six ex-smokers with normal lung function. MiR-335-5p and miR-335-3p were significantly downregulated in lung fibroblasts from current compared to ex-smokers (false discovery rate (FDR) <0.05). Differential miR-335-5p expression was validated with RT-qPCR (
-value = 0.01). The results were validated in lung tissue from current and ex-smokers and in bronchial biopsies from non-diseased smokers and never-smokers (
-value <0.05). The methylation pattern of the miR-335 host gene, determined by methylation-specific qPCR, did not differ between current and ex-smokers. To obtain insights into the genes regulated by miR-335-5p in fibroblasts, we overlapped all proven miR-335-5p targets with our previously published miRNA targetome data in lung fibroblasts. This revealed
,
, and
as likely targets of miR-335-5p in lung fibroblasts. Our study indicates that miR-335-5p downregulation due to current smoking may affect its function in lung fibroblasts by targeting
,
and
.
The Epstein–Barr virus (EBV) can cause a wide variety of cancers upon infection of different cell types and induces a highly variable composition of the tumor microenvironment (TME). This TME ...consists of both innate and adaptive immune cells and is not merely an aspecific reaction to the tumor cells. In fact, latent EBV-infected tumor cells utilize several specific mechanisms to form and shape the TME to their own benefit. These mechanisms have been studied largely in the context of EBV+ Hodgkin lymphoma, undifferentiated nasopharyngeal carcinoma, and EBV+ gastric cancer. This review describes the composition, immune escape mechanisms, and tumor cell promoting properties of the TME in these three malignancies. Mechanisms of susceptibility which regularly involve genes related to immune system function are also discussed, as only a small proportion of EBV-infected individuals develops an EBV-associated malignancy.
Summary
Individually, tissue and soluble markers involved in the programmed cell death protein 1/programmed death‐ligand (PD‐1/PD‐L) axis have been described as biomarkers with clinical value in ...classical Hodgkin lymphoma (cHL). In the context of the success of immune checkpoint blockade therapy in cHL, it is interesting to discover whether plasma levels of proteins in the PD‐1/PD‐L axis are a reflection of expression by the corresponding tissue. Paired tissue and plasma samples of cHL patients were collected and analysed for PD‐1, PD‐L1 and PD‐L2 levels. In addition, vascular endothelial growth factor (VEGF) and CD83, molecules regarded to influence the expression of PD‐1, PD‐L1 and/or PD‐L2, were included. PD‐L1 was upregulated in the plasma of cHL patients compared to healthy controls and correlated well with several clinical parameters. Strong PD‐L1 expression in the tumour microenvironment contributed to high soluble (s)PD‐L1 levels, although there was no direct correlation between plasma PD‐L1 levels and total expression of PD‐L1 in corresponding cHL tissue. Interestingly, we observed a positive correlation between VEGF and PD‐1 levels in both tissue and plasma. In conclusion, although PD‐L1 is a promising soluble biomarker in cHL, its levels do not reflect the total tissue expression. Future studies focusing on PD‐L1 as a predictor for immune checkpoint treatment response, should include both biopsy and plasma samples.
Primary cutaneous diffuse large B-cell lymphoma, leg type (PCDLBCL-LT) and primary cutaneous follicle center lymphoma with a diffuse population of large cells (PCFCL-LC) are both primary cutaneous ...B-cell lymphomas with large-cell morphology (CLBCL) but with different clinical characteristics and behavior. In systemic diffuse large B-cell lymphoma, not otherwise specified (DLBCL-NOS), gene-expression profiling (GEP) revealed two molecular subgroups based on their cell-of-origin (COO) with prognostic significance: the germinal center B-cell-like (GCB) subtype and the activated B-cell-like (ABC) subtype. This study investigated whether COO classification is a useful tool for classification of CLBCL. For this retrospective study, 51 patients with PCDLBCL-LT and 15 patients with PCFCL-LC were analyzed for their COO according to the immunohistochemistry-based Hans algorithm and the NanoString GEP-based Lymph2Cx algorithm. In PCFCL-LC, all cases (100%) classified as GCB by both Hans and Lymph2Cx. In contrast, COO classification in PCDLBCL-LT was heterogeneous. Using Hans, 75% of the PCDLBCL-LT patients classified as non-GCB and 25% as GCB, while Lymph2Cx classified only 18% as ABC, 43% as unclassified/intermediate, and 39% as GCB. These COO subgroups did not differ in the expression of BCL2 and IgM, mutations in
MYD88
and/or
CD79B
, loss of
CDKN2A
, or survival. In conclusion, PCFCL-LC uniformly classified as GCB, while PCDLBCL-LT classified along the COO spectrum of DLBCL-NOS using the Hans and Lymph2Cx algorithms. In contrast to DLBCL-NOS, the clinical relevance of COO classification in CLBCL using these algorithms has limitations and cannot be used as an alternative for the current multiparameter approach in differentiation of PCDLBCL-LT and PCFCL-LC.
In classical Hodgkin lymphoma (CHL), 20%-30% of patients experience relapse or progressive disease after initial treatment. The pathogenesis and biology of treatment failure are still poorly ...understood, in part because the molecular phenotype of the rare malignant Hodgkin Reed-Sternberg (HRS) cells is difficult to study. Here we examined microdissected HRS cells from 29 CHL patients and 5 CHL-derived cell lines by gene expression profiling. We found significant overlap of HL-specific gene expression in primary HRS cells and HL cell lines, but also differences, including surface receptor signaling pathways. Using integrative analysis tools, we identified target genes with expression levels that significantly correlated with genomic copy-number changes in primary HRS cells. Furthermore, we found a macrophage-like signature in HRS cells that significantly correlated with treatment failure. CSF1R is a representative of this signature, and its expression was significantly associated with progression-free and overall survival in an independent set of 132 patients assessed by mRNA in situ hybridization. A combined score of CSF1R in situ hybridization and CD68 immunohistochemistry was an independent predictor for progression-free survival in multivariate analysis. In summary, our data reveal novel insights into the pathobiology of treatment failure and suggest CSF1R as a drug target of at-risk CHL.
ABSTRACT
Myc is a well‐known transcription factor with important roles in cell cycle, apoptosis, and cellular transformation. Long noncoding RNAs (lncRNAs) have recently emerged as an important class ...of regulatory RNAs. Here, we show that lncRNAs are a main component of the Myc‐regulated transcriptional program using the P493‐6 tetracycline‐repressible myc model. We demonstrate that both Myc‐induced mRNAs and lncRNAs are significantly enriched for Myc binding sites. In contrast to Myc‐repressed mRNAs, Myc‐repressed lncRNAs are significantly enriched for Myc binding sites. Subcellular localization analysis revealed that compared to mRNAs, lncRNAs more often have a specific subcellular localization with a markedly higher percentage of nuclear enrichment within the Myc‐repressed lncRNA set. Parallel analysis of differentially expressed lncRNAs and mRNAs identified 105 juxtaposed lncRNA‐mRNA pairs, indicative for regulation in cis. To support the potential relevance of the Myc‐regulated lncRNAs in cellular transformation, we analyzed their expression in primary Myc‐high and Myc‐low B‐cell lymphomas. In total, 54% of the lncRNAs differentially expressed between the lymphoma subsets were identified as Myc‐regulated in P493‐6 cells. This study is the first to show that lncRNAs are an important factor within the Myc‐regulated transcriptional program and indicates a marked difference between Myc‐repressed lncRNAs and mRNAs.—Winkle, M., van den Berg, A., Tayari, M., Sietzema, J., Terpstra, M., Kortman, G., de Jong, D., Visser, L., Diepstra, A., Kok, K., Kluiver, J. Long noncoding RNAs as a novel component of the Myc transcriptional network. FASEB J. 29, 2338‐2346 (2015). www.fasebj.org
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