Cigarette smoke induces apoptosis in the follicle-associated epithelium of murine Peyer's patches

Background: Recently, cigarette smoking has been associated with the development of several auto-immune diseases, including rheumatoid arthritis and inflammatory bowel disease (IBD). The cellular and molecular mechanisms through which cigarette smoking predisposes to IBD are unknown. Cigarette smoke-induced apoptosis is described in several in vivo and in vitro experiments, and might play a role in the pathogenesis of several smoke-associated diseases. The aim of this study was to quantify apoptosis in normal murine Follicle-Associated Epithelium (FAE) and compare this to apoptosis in FAE of smoking mice. Methods: 8 C57BL/6 male mice were exposed to cigarette smoke for 24 weeks (chronic exposure); a control group of 8 mice was exposed to air during the same period. After 24 weeks the mice were sacrificed and Peyer’s patches of each mouse were dissected for histology. Immunohistochemistry for caspase-3 was performed on paraffin-embedded tissue sections of 11 Peyer’s patches of smoking animals and 11 Peyer’s patches of controls. To compare apoptotic activities between smokers and controls, the apoptotic index (percentage of apoptotic cells per 100 cells) in the FAE was calculated. An unpaired student T-test was applied. Results: A statistically significant increase in apoptosis of FAE cells was observed in smoking mice compared to air-exposed mice (P=0.002). In the FAE of smoking animals, the mean apoptotic index was 1.82 with a range of 1.11 to 3.00, whereas the mean apoptotic index in non-smoking animals was 0.92 (range 0.24 -2.06). Most apoptotic cells in both groups were seen at the apex of the FAE. Conclusion: We quantified rates of apoptosis in the FAE of murine Peyer’s patches. Furthermore we compared apoptosis in the FAE of smoking mice versus non-smoking siblings and observed an increased apoptotic index in the FAE of smoking animals. Our results demonstrate that cigarette smoke induces a significant increase of apoptosis in the FAE of murine Peyer’s patches and may point to a role for smoking in the pathogenesis of intestinal inflammation. Further investigation needs to clarify whether this increase in apoptosis influences normal function of the FAE

Primary intestinal aspergillosis resulting in acute intestinal volvulus after autologous stem cell transplantation in a patient with relapsed non-Hodgkin lymphoma : report on a rare infectious complication and a review of the literature

Objectives: Since primary intestinal aspergillosis is a severe infectious complication with a high morbidity and mortality in immunocompromised patients, we want to draw attention to this rare entity and the importance of early recognition. Methods: We report a case of documented primary intestinal aspergillosis in a patient receiving an autologous stem cell transplantation (SCT). Furthermore, this article gives a short reflection on the occurrence of invasive aspergillosis in autologous SCT and the value of serum galactomannan levels based on literature search and linked with the case. Results: In this case the patient presented on day +8 after autologous SCT for a relapsed diffuse large B-cell lymphoma with an acute abdomen with urgent need for surgical intervention. Biopsy revealed the presence of fungal colonies due to aspergillosis and voriconazole was started. Until that day the systematically taken serum galactomannan tests were all negative or pending. Initially there was some resistance to perform surgery in the presence of neutropenia and thrombocytopenia but in the end it provided the definitive diagnosis and should not be delayed. Until now this patient is in good health and retains a complete remission. Conclusion: With this case, we would like to emphasize that early recognition of primary intestinal aspergillosis is of the utmost importance as it is a rare but serious infectious complication. It should be included in the differential diagnosis of neutropenic patients with sudden onset abdominal pain and ongoing fever, even in the absence of a positive serum galactomannan

Thrombosis of an Arteria Lusoria with Secondary Subclavian Steal Syndrome and Swallowing Difficulties

We report a case of an arteria lusoria causing swallowing difficulties known as dysphagia lusoria. Although the presence of an arteria lusoria is quite common, dysphagia lusoria is relatively rare. Interestingly, our patient also presented with a concurrent aneurysmal dilatation, known as a Kommerell’s diverticulum, at the aortic origin. Complete thrombosis of the artery and flow reversal in the right cervical artery resulting in an asymptomatic subclavian steal syndrome was also seen. No underlying primary pro-thrombotic defects were identified but due to the presence of locally advanced prostate cancer, a paraneoplastic phenomenon was suspected

A Novel Splice Variant in the N-propeptide of COL5A1 Causes an EDS Phenotype with Severe Kyphoscoliosis and Eye Involvement

Background: The Ehlers-Danlos Syndrome (EDS) is a heritable connective tissue disorder characterized by hyperextensible skin, joint hypermobility and soft tissue fragility. The classic subtype of EDS is caused by mutations in one of the type V collagen genes (COL5A1 and COL5A2). Most mutations affect the type V collagen helical domain and lead to a diminished or structurally abnormal type V collagen protein. Remarkably, only two mutations were reported to affect the extended, highly conserved N-propeptide domain, which plays an important role in the regulation of the heterotypic collagen fibril diameter. We identified a novel COL5A1 N-propeptide mutation, resulting in an unusual but severe classic EDS phenotype and a remarkable splicing outcome. Methodology/Principal Findings: We identified a novel COL5A1 N-propeptide acceptor-splice site mutation (IVS6-2A>G, NM_000093.3_c.925-2A>G) in a patient with cutaneous features of EDS, severe progressive scoliosis and eye involvement. Two mutant transcripts were identified, one with an exon 7 skip and one in which exon 7 and the upstream exon 6 are deleted. Both transcripts are expressed and secreted into the extracellular matrix, where they can participate in and perturb collagen fibrillogenesis, as illustrated by the presence of dermal collagen cauliflowers. Determination of the order of intron removal and computational analysis showed that simultaneous skipping of exons 6 and 7 is due to the combined effect of delayed splicing of intron 7, altered pre-mRNA secondary structure, low splice site strength and possibly disturbed binding of splicing factors. Conclusions/Significance: We report a novel COL5A1 N-propeptide acceptor-splice site mutation in intron 6, which not only affects splicing of the adjacent exon 7, but also causes a splicing error of the upstream exon 6. Our findings add further insights into the COL5A1 splicing order and show for the first time that a single COL5A1 acceptor-splice site mutation can perturb splicing of the upstream exon

A challenging diagnosis of a nonsecretor plasma cell dyscrasia with pleomorphic plasmablastic morphology

This report highlights the importance of integrating clinical, radiological, genetic, and pathological laboratory findings to make a correct diagnosis especially with challenging and rare entities

Comprehensive characterization of LEDGF/p75 in a HIV-1-infected patient cohort

BACKGROUND: Lens epithelium derived growth factor/transcriptional co-activator p75 (LEDGF/p75) is an important cellular co-factor for the HIV enzyme integrase. In the present study, we evaluated if genetic variation in the LEDGF/p75 gene and mRNA expression levels might explain differences in HIV disease progression. METHODS: Samples were derived from a therapy-naïve patient cohort from the Ghent University Hospital and from the long-term-non-progressor patient Spanish RIS cohort. A comprehensive genomic scan of the coding region and 3’UTR of LEDGF/p75 was performed using high resolution melting curve analysis and Sanger sequencing to identify single nucleotide polymorphisms (SNPS). In addition, LEDGF/p75 mRNA expression levels were determined from patient PBMCs using RT-qPCR with validated reference genes for normalization. RESULTS: In total 325 patient samples were investigated, of which 291 (90%) of Caucasian and 34 (10%) of African origin, and among which a large group of Elite controllers (n=49) and Viremic controllers (n=62). In these samples, 24 SNPs were analyzed, including 5 in the coding region (2 synonymous and 3 non-synonymous), 17 in the flanking non-coding regions and in the 3’UTR, and two additional tagSNPs as described by Madlala et al. (Aids, 2011) in two South African cohorts. One SNP in the 3’UTR region (rs2737835, n=46) had a higher representation in Caucasian Elite controllers and was correlated with lower LEDGF/p75 mRNA levels (P=0.047) and with a slower CD4 decline (P= 0.042). rs2737828 (n=13) was under-represented in Caucasian HIV patients and linked to lower LEDGF/p75 expression (P=0.013). The presence of intron SNP (rs16933270, n=6) was associated with a slower CD4 decline in African patients (P=0.017), and this CD4 decline was comparable with that of African slow disease progressors. Interestingly, the presence of one tagSNP (rs12339417, n=95) was significantly correlated with a decreased viral load, but in contrast to the results of Madlala et al. (Aids, 2011), this SNP was not correlated with the CD4 slope and neither with LEDGF/p75 mRNA levels. CONCLUSIONS: Although the data of the present investigation was not entirely comparable with the results of Madlala et al. (Aids, 2011), our data supports their hypothesis that host factors influence HIV disease progression. The observed differences between the European and South African cohorts may be of ethnical origin, or due to different infection phases. In the investigated cohorts, two SNPs were associated with lower LEDGF/p75 mRNA expression in Caucasians, and one SNP was associated with slower disease progression in Africans. The significant correlation with the tagSNP (rs12339417) and the decreased viral load is surprising as this was not correlated with a delayed CD4 decline, nor with LEDGF/p75 expression. This might indicate that either conformational changes or factors upstream of mRNA transcription might influence the action of LEDGF/p75 in these HIV patients

G9a/GLP targeting in MM promotes autophagy-associated apoptosis and boosts proteasome inhibitor-mediated cell death

Multiple myeloma (MM) is an (epi)genetic highly heterogeneous plasma cell malignancy that remains mostly incurable. Deregulated expression and/or genetic defects in epigenetic-modifying enzymes contribute to high-risk disease and MM progression. Overexpression of the histone methyltransferase G9a was reported in several cancers, including MM, correlating with disease progression, metastasis, and poor prognosis. However, the exact role of G9a and its interaction partner G9a-like protein (GLP) in MM biology and the underlying mechanisms of action remain poorly understood. Here, we report that high G9a RNA levels are associated with a worse disease outcome in newly diagnosed and relapsed MM patients. G9a/GLP targeting using the specific G9a/GLP inhibitors BIX01294 and UNC0638 induces a G 1 -phase arrest and apoptosis in MM cell lines and reduces primary MM cell viability. Mechanistic studies revealed that G9a/GLP targeting promotes autophagy-associated apoptosis by inactivating the mTOR/4EBP1 pathway and reducing c-MYC levels. Moreover, genes deregulated by G9a/GLP targeting are associated with repressive histone marks. G9a/GLP targeting sensitizes MM cells to the proteasome inhibitors (PIs) bortezomib and carfilzomib, by (further) reducing mTOR signaling and c-MYC levels and activating p-38 and SAPK/JNK signaling. Therapeutic treatment of STGM1 mice with BIX01294 delayed in vivo MM tumor growth, and cotreatment with bortezomib resulted in a further reduction in tumor burden and a significantly prolonged survival. In conclusion, we provide evidence that the histone methyltransferases G9a/GLP support MM cell growth and survival by blocking basal autophagy and sustaining high c-MYC levels. G9a/GLP targeting represents a promising strategy to improve PI-based treatment in patients with high G9a/GLP levels

Maternal embryonic leucine zipper kinase is a novel target for diffuse large B cell lymphoma and mantle cell lymphoma

Diffuse large B cell lymphoma (DLBCL) and mantle cell lymphoma (MCL) are among the most aggressive B cell non-Hodgkin lymphomas. Maternal embryonic leucine zipper kinase (MELK) plays a role in cancer cell cycle progression and is associated with poor prognosis in several cancer cell types. In this study, the role of MELK in DLBCL and MCL and the therapeutic potential of MELK targeting is evaluated. MELK is highly expressed in DLBCL and MCL patient samples, correlating with a worse clinical outcome in DLBCL. Targeting MELK, using the small molecule OTSSP167, impaired cell growth and survival and induced caspase-mediated apoptosis in the lymphoma cells. Western blot analysis revealed that MELK targeting decreased the phosphorylation of FOXM1 and the protein levels of EZH2 and several mitotic regulators, such as Cdc25B, cyclin B1, Plk-1, and Aurora kinases. In addition, OTSSP167 also sensitized the lymphoma cells to the clinically relevant Bcl-2 inhibitor venetoclax by strongly reducing Mcl1 levels. Finally, OTSSP167 treatment of A20-inoculated mice resulted in a significant prolonged survival. In conclusion, targeting MELK with OTSSP167 induced strong anti-lymphoma activity both in vitro and in vivo. These findings suggest that MELK could be a potential new target in these aggressive B cell malignancies

Daratumumab With Cetrelimab, an Anti-PD-1 Monoclonal Antibody, in Relapsed/Refractory Multiple Myeloma

Patients with relapsed or refractory multiple myeloma have an immunosuppressive state with upregulation of programmed death receptor-1 on immune effector cells. Treatment with daratumumab plus cetrelimab, which targets the programmed death receptor-1, was evaluated in 9 patients with relapsed or refractory multiple myeloma. No new safety concerns were identified for the combination. The potential clinical benefit of daratumumab plus cetrelimab remains uncertain. Background: Daratumumab is approved for relapsed or refractory multiple myeloma (RRMM) as monotherapy or in combination regimens. We evaluated daratumumab plus cetrelimab, a programmed death receptor-1 inhibitor, in RRMM. Patients and Methods: This open-label, multiphase study enrolled adults with RRMM with >= 3 prior lines of therapy. Part 1 was a safety run-in phase examining dose-limiting toxicities of daratumumab (16 mg/kg intravenously weekly for cycles 1-2, biweekly for cycles 3-6, and monthly thereafter) plus cetrelimab (240 mg intravenously biweekly, all cycles). In Parts 2 and 3, patients were to be randomized to daratumumab with or without cetrelimab (same schedule as Part 1). Endpoints included safety, overall response rate, pharmacokinetics, and biomarker analyses. Results: Nine patients received daratumumab plus cetrelimab in the safety run-in, and 1 received daratumumab in Part 2 before administrative study termination following a data monitoring committee's global recommendation to stop any trial including daratumumab combined with inhibitors of programmed death receptor-1 or its ligand (programmed death-ligand 1). The median follow-up times were 6.7 months (safety run-in) and 0.3 months (Part 2). No dose-limiting toxicities occurred. All 10 patients had >= 1 treatment-emergent adverse event; 7 patients had grade 3 to 4 treatment-emergent adverse events, and none led to treatment discontinuation or death. In the safety run-in, 7 (77.7%) patients had > 1 infusion-related reaction (most grade 1-2), and 1 had a grade 2 immune-mediated reaction. Among safety run-in patients, the overall response rate was 44.4%. Conclusions: No new safety concerns were identified for daratumumab plus cetrelimab in RRMM. The short study duration and small population limit complete analysis of this combination. (C) 2020 The Author(s). Published by Elsevier Inc

The anaphase-promoting complex/cyclosome : a new promising target in diffuse large B-cell lymphoma and mantle cell lymphoma

BACKGROUND: The aggressive B-cell non-Hodgkin lymphomas diffuse large B-cell lymphoma (DLBCL) and mantle cell lymphoma (MCL) are characterised by a high proliferation rate. The anaphase-promoting complex/cyclosome (APC/C) and its co-activators Cdc20 and Cdh1 represent an important checkpoint in mitosis. Here, the role of the APC/C and its co-activators is examined in DLBCL and MCL. METHODS: The expression and prognostic value of Cdc20 and Cdh1 was investigated using GEP data and immunohistochemistry. Moreover, the therapeutic potential of APC/C targeting was evaluated using the small-molecule inhibitor proTAME and the underlying mechanisms of action were investigated by western blot. RESULTS: We demonstrated that Cdc20 is highly expressed in DLBCL and aggressive MCL, correlating with a poor prognosis in DLBCL. ProTAME induced a prolonged metaphase, resulting in accumulation of the APC/C-Cdc20 substrate cyclin B1, inactivation/degradation of Bcl-2 and Bcl-xL and caspase-dependent apoptosis. In addition, proTAME strongly enhanced the anti-lymphoma effect of the clinically relevant agents doxorubicin and venetoclax. CONCLUSION: We identified for the first time APC/C as a new, promising target in DLBCL and MCL. Moreover, we provide evidence that Cdc20 might be a novel, independent prognostic factor in DLBCL and MCL