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Background: Primary pulmonary paragangliomas are extremely rare neuroendocrine tumor, counting less than 1% of all paragangliomas. The incidence of paragangliomas range between 2– 8 per million in a year. The most common site of origin is the superior paraaortic region between the diaphragm and the lower renal poles (approximately 46% of all cases), and particularly in and around the renal hilus. Most pulmonary paragangliomas are nonfunctional and result in no evident clinical symptoms. Some patients develop respiratory symptoms, such as a cough, chest pain, or dyspnea, as in our case. Case presentation: A 71-year-old woman came to our attention for cough. Active smoker of 56 p/y, her medical history consisted of a myocardial infarction, anxious-depressive syndrome, hypertension, diabetes, obesity (BMI 37.3) and Hashimoto thyroiditis. The chest radiography revealed a rounded opacity of the middle lobe. Then, a computerized tomography (CT) showing the presence of a 2.6 cm solid lesion, oval in shape, with regular margins, located in the medial segment of the middle lobe. On gross examination, a well-demarcated neoplasm, with white-brown cut surface and solid consistency was found. The tumor cells appear to be arranged in a typical nest pattern supported by a thin vascular framework producing the classic ‘zellballen’ or basket pattern. Immunohistochemical staining showing positivity for CgA, Syn and S100 (immunostaining revealed of the presence of the classic “substentacular” cells). Conclusion: Primary pulmonary paragangliomas are rare entities and their differential diagnosis with carcinoid tumors, more typical for this site, is not always easy and lies in subtle morphological and immunophenotypic differences. A correct diagnosis is important since, in 50% of the patients, mutations in tumor susceptibility genes have been reported, thus a genetic testing and counseling should be considered.

Malignant pleural mesothelioma (MPM) is an aggressive cancer, related to asbestos exposure, which has a dismal prognosis. MPM diagnosis is late and often challenging, suggesting the need to identify more reliable molecular biomarkers. Here, we set out to identify differentially expressed miRNAs in epithelioid, biphasic, and sarcomatoid MPMs versus normal mesothelium and explored specific miRNA contribution to mesothelial tumorigenesis. We screened an LNA™-based miRNA-microrray with 14 formalin-fixed paraffin-embedded (FFPE) MPMs and 6 normal controls. Through real-time qRT-PCR we extended the analysis of a miRNA subset and further investigated miR-320a role through state-of-the-art techniques. We identified 16 upregulated and 32 downregulated miRNAs in MPMs versus normal tissue, including the previously identified potential biomarkers miR-21, miR-126, miR-143, miR-145. We showed in an extended series that miR-145, miR-10b, and miR-320a levels can discriminate tumor versus controls with high specificity and sensitivity. We focused on miR-320a because other family members were found downregulated in MPMs. However, stable miR-320a ectopic expression induced higher proliferation and migration ability, whereas miR-320a silencing reduced these processes, not supporting a classic tumor-suppressor role in MPM cell lines. Among putative targets, we found that miR-320a binds the 3′-UTR of the immune inhibitory receptor ligand PDL1 and, consistently, miR-320a modulation affects PDL1 levels in MPM cells. Finally, we showed that p53 over-expression induces the upregulation of miR-320a, along with miR-200a and miR-34a, both known to target PDL1, and reduces PDL1 levels in MPM cells. Our data suggest that PDL1 expression might be due to a defective p53-regulated miRNA response, which could contribute to MPM immune evasion or tumorigenesis through tumor-intrinsic roles.

Malignant mesothelioma (MM) is an aggressive asbestos‐related cancer of the serous membranes. Despite intensive treatment regimens, MM is still a fatal disease, mainly due to the intrinsic resistance to current therapies and the lack of predictive markers and new valuable molecular targets. Protein arginine methyltransferase 5 (PRMT5) inhibition has recently emerged as a potential therapy against methylthioadenosine phosphorylase (MTAP)‐deficient cancers, in which the accumulation of the substrate 5'‐methylthioadenosine (MTA) inhibits PRMT5 activity, thus sensitizing the cells to further PRMT5 inhibition. Considering that the MTAP gene is frequently codeleted with the adjacent cyclin‐dependent kinase inhibitor 2A (CDKN2A) locus in MM, we assessed whether PRMT5 could represent a therapeutic target also for this cancer type. We evaluated PRMT5 expression, the MTAP status and MTA content in normal mesothelial and MM cell lines. We found that both administration of exogenous MTA and stable PRMT5 knock‐down, by short hairpin RNAs (shRNAs), selectively reduced the growth of MTAP‐deleted MM cells. We also observed that PRMT5 knock‐down in MTAP‐deficient MM cells reduced the expression of E2F1 target genes involved in cell cycle progression and of factors implicated in epithelial‐to‐mesenchymal transition. Therefore, PRMT5 targeting could represent a promising new therapeutic strategy against MTAP‐deleted MMs.

The precise B cell of origin and molecular pathogenesis of nodal marginal zone lymphoma (NMZL) remain poorly defined. To date, due to the rarity of NMZL, the vast majority of already-published studies have been conducted on a limited number of samples and the technical approach to analyze the immunoglobulin genes was of amplifying rearranged variable region genes with the classical direct sequencing of the PCR products followed by cloning. Here, we studied the B cell Ig heavy-chain repertoires by next-generation sequencing (NGS) in 30 NMZL cases. Most of the cases were mutated (20/28; 71.5%) with homologies to the respective germ line genes ranging from 85 to 97, 83%, whereas 8/28 (28.5%) were unmutated. In addition, our results show that NMZL cases have a biased usage of specific immunoglobulin heavy-chain variable (IGHV) region genes. Moreover, we documented intraclonal diversity in all (100%) of the mutated cases and ongoing somatic hypermutations (SHM) have been confirmed by hundreds of reads. We analyzed the mutational pattern to detect and quantify antigen selection pressure and we found a positive selection in 4 cases, whereas in the remaining cases there was an unspecific stimulation. Finally, the disease-specific survival and the progression-free survival were significantly different between cases with mutated and unmutated IGHV genes, pointing out mutational status as a possible new biomarker in NMZL. Electronic supplementary material The online version of this article (10.1007/s00428-019-02712-8) contains supplementary material, which is available to authorized users.

Simple Summary In the tumor microenvironment, interaction among tumor cells, immune cells, stromal cells, and the extracellular matrix is vital to support pro-tumor mechanisms such as drug resistance and metastases. Malignant pleural mesothelioma has a unique and complex tumor microenvironment. Several reports underlined the key role of immune and stromal cells in tumorigenesis and progression of mesothelioma. These non-cancer cells, via a reciprocal informational exchange with tumor cells, established a chronic inflammatory microenvironment that support the malignancy and the chemoresistant phenotype of the tumor. The knowledge of the cellular and molecular mechanisms underlying tumor microenvironment interconnection was recently considered a crucial point for the design of more effective therapeutic strategies. In this review, we summarize the molecular mechanisms by which stroma and immune cells support the malignancy of mesothelioma and their potential therapeutic targeting. Abstract Several studies have reported that cellular and soluble components of the tumor microenvironment (TME) play a key role in cancer-initiation and progression. Considering the relevance and the complexity of TME in cancer biology, recent research has focused on the investigation of the TME content, in terms of players and informational exchange. Understanding the crosstalk between tumor and non-tumor cells is crucial to design more beneficial anti-cancer therapeutic strategies. Malignant pleural mesothelioma (MPM) is a complex and heterogenous tumor mainly caused by asbestos exposure with few treatment options and low life expectancy after standard therapy. MPM leukocyte infiltration is rich in macrophages. Given the failure of macrophages to eliminate asbestos fibers, these immune cells accumulate in pleural cavity leading to the establishment of a unique inflammatory environment and to the malignant transformation of mesothelial cells. In this inflammatory landscape, stromal and immune cells play a driven role to support tumor development and progression via a bidirectional communication with tumor cells. Characterization of the MPM microenvironment (MPM-ME) may be useful to understand the complexity of mesothelioma biology, such as to identify new molecular druggable targets, with the aim to improve the outcome of the disease. In this review, we summarize the known evidence about the MPM-ME network, including its prognostic and therapeutic relevance.

BACKGROUND Human herpesvirus-8 (HHV8) is a lymphotropic virus associated with different lymphoproliferative disorders, including primary effusion lymphoma (PEL), multicentric Castleman's disease (MCD), diffuse large B-cell lymphomas, not otherwise specified, and the rare entity known as germinotropic lymphoproliferative disorder (GLPD). In PELs and GLPD the neoplastic cells also contain Epstein-Barr virus (EBV). In addition, occasional cases with atypical and overlapping features among these entities have been recognised, suggesting that the spectrum of the HHV8-related lesions may not be fully characterised. AIMS Here, we report two cases of lymphoproliferative disorder associated with HHV8 and EBV that further expand the spectrum of HHV8/EBV-positive lymphoproliferative disease. METHODS AND RESULTS Case 1 represented HHV8/EBV-positive extracavitary nodal PEL followed by pleural PEL. The striking characteristic of this case was the almost focal and intrasinusoidal localisation of the neoplastic cells and the association with Castleman's disease features. In the second case, we found the entire spectrum of HHV8-related disorders, i.e. MCD, GLPD, and PEL, coexisting in the same lymph node, underlining the variability, possible overlap and evolution among these entities. Both cases were well analysed with immunohistochemistry, determination of the EBV latency programme, and molecular analysis for clonality of immnoglobulin genes. In both patients, the disease followed an unexpected indolent course, both being still alive after 8 and 12 months, respectively. CONCLUSION Our findings represent further evidence of the overlap among HHV8/EBV-positive lymphoproliferative disorders, and underline a grey zone that requires further study; they further confirm the experimental evidence that lytic EBV replication influences HHV8-related tumorigenesis.

Nasal polyp is a non neoplastic lesion of the respiratory mucosa. In few cases, it can be possible to detech the presence of cholesterolgranuloma. We present the case of a 55 year-old patient affected by a nasal lesion, localized in sphenoethmoidal recess, with particular microscopic feature and a review of the literature.

Advanced chronic kidney disease (CKD) is associated with poor outcomes in patients undergoing surgical aortic valve replacement, while its prognostic role in transcatheter aortic valve replacement ...

Context Paget disease of bone (PDB) is a metabolic bone disease whose genetic cause remains unknown in up to 50% of familial patients. Objective Our aim was to investigate the underlying genetic defect in a large pedigree with a severe, early onset, autosomal dominant form of PDB across 3 generations. Methods Whole exome sequencing was performed in affected and unaffected family members, and then mutation screening was replicated in a sample of PDB patients with early-onset, polyostotic PDB. Results We identified a frameshift D107Rfs*3 mutation in PFN1 (encoding for profilin 1, a highly conserved regulator of actin-polymerization and cell motility) causing the truncation of the C-terminal part of the protein. The mutation was also detected in a 17-year-old asymptomatic family member who upon biochemical and radiological analyses was indeed found to be affected. Sequencing of the entire PFN1 coding region in unrelated PDB patients identified the same mutation in 1 patient. All mutation carriers had a reduced response to bisphosphonates, requiring multiple zoledronate infusions to control bone pain and achieve biochemical remission over a long term. In vitro osteoclastogenesis in peripheral blood mononuclear cells (PBMCs) from mutation carriers showed a higher number of osteoclasts with PDB-like features. A similar phenotype was observed upon PFN1 silencing in murine bone marrow-derived monocytes, suggesting that the frameshift PFN1 mutation confers a loss of function in profilin 1 activity that induces PDB-like features in the osteoclasts, likely due to enhanced cell motility and actin ring formation. Conclusions Our findings indicate that PFN1 mutation causes an early onset, polyostotic PDB-like disorder.

The characteristics of extra-nasopharyngeal angiofibromas tend to be different from angiofibromas of the nasopharynx according to patient gender, patient age, prevalence, affected site, pathogenesis, and clinical and epidemiological features. We report a case of an extra-nasopharyngeal angiofibroma in a 28-year-old man referred to the ENT Clinic for right-sided epistaxis, airflow impairment and nasal swelling. The right nostril was completely occluded works by a reddish-yellow mass that bled easily. The computed tomography scan revealed an “inhomogeneous solid lesion in the nasal fossa”. With the patient under general anesthesia, the formation in the anterior portion of the right side of the nasal septum was removed up to its vascular base. Although electrical cauterization efficiently controlled the bleeding, we abraded the sub-perichondral area to prevent further bleeding as well as recurrence. The histological exam report confirmed the diagnosis of angiofibroma. As in our case, epistaxis is commonly the presenting sign of angiofibroma. Yet its onset was peculiar, given that the bleeding started with a low impact trauma. The nasal swelling was also a relevant feature as well as the breathing impairment. Although uncommon, nasal septal angiofibromas should considered in patients with epistaxis.

Melanoma and non-small-cell lung carcinoma (NSCLC) cell lines are characterized by an intrinsic population of cancer stem-like cells (CSC), and high expression of detoxifying isozymes, the aldehyde dehydrogenases (ALDHs), regulating the redox state. In this study, using melanoma and NSCLC cells, we demonstrate that ALDH3A1 isozyme overexpression and activity is closely associated with a highly aggressive mesenchymal and immunosuppressive profile. The contribution of ALDH3A1 to the stemness and immunogenic status of melanoma and NSCLC cells was evaluated by their ability to grow in 3D forming tumorspheres, and by the expression of markers for stemness, epithelial to mesenchymal transition (EMT), and inflammation. Furthermore, in specimens from melanoma and NSCLC patients, we investigated the expression of ALDH3A1, PD-L1, and cyclooxygenase-2 (COX-2) by immunohistochemistry. We show that cells engineered to overexpress the ALDH3A1 enzyme enriched the CSCs population in melanoma and NSCLC cultures, changing their transcriptome. In fact, we found increased expression of EMT markers, such as vimentin, fibronectin, and Zeb1, and of pro-inflammatory and immunosuppressive mediators, such as NFkB, prostaglandin E2, and interleukin-6 and -13. ALDH3A1 overexpression enhanced PD-L1 output in tumor cells and resulted in reduced proliferation of peripheral blood mononuclear cells when co-cultured with tumor cells. Furthermore, in tumor specimens from melanoma and NSCLC patients, ALDH3A1 expression was invariably correlated with PD-L1 and the pro-inflammatory marker COX-2. These findings link ALDH3A1 expression to tumor stemness, EMT and PD-L1 expression, and suggest that aldehyde detoxification is a redox metabolic pathway that tunes the immunological output of tumors.

Malignant mesothelioma (MM) is a very aggressive asbestos-related cancer, whose incidence is increasing worldwide. Unfortunately, no effective therapies are currently available and the prognosis is extremely poor. Recently, the anti-helminthic drug pyrvinium pamoate has attracted a strong interest for its anti-cancer activity, which has been demonstrated in many cancer models. Considering the previously established inhibitory effect of pyrvinium pamoate on the Wnt/β-catenin pathway and given the important role of this pathway in MM, we investigated the potential anti-tumor activity of this drug in MM cell lines. We observed that pyrvinium pamoate significantly impairs MM cell proliferation, cloning efficiency, migration, and tumor spheroid formation. At the molecular level, our data show that pyrvinium pamoate down-regulates the expression of β-catenin and Wnt-regulates genes. Overall, our study suggests that the repurposing of pyrvinium pamoate for MM treatment could represent a new promising therapeutic approach.

Lipomatous hypertrophy is an uncommon benign lesion of the atrium, generally asymptomatic, characterized by unencapsulated accumulation of adipose tissue entrapping cardiomyocytes. This pathology generally remains unnoticed and often emerges as an occasional finding. Here, we report two cases from our hospital including a review of the available literature.

Objectives: Chronic lymphocytic leukemia (CLL) is the most common type of leukemia in Western populations, being rarer in Asian and African people. It has been suggested that patients with CLL from Africa might have a more aggressive disease compared with white patients. In this study, we aimed to identify genetic factors that may account for this difference. Methods: We analyzed immunoglobulin heavy chain (IGH) genes' mutational status by performing next-generation sequencing in 25 Senegalese and 50 Italian patients with CLL. Results: We found that Senegalese patients more frequently had adverse prognostic factors and an unmutated profile. Furthermore, we documented that IGHV1 (IGHV1-69), IGHD3, and IGHJ6 were significantly more frequent in Senegalese patients, whereas IGHV3-30 was common and limited to the Italian cohort. Stereotyped receptors commonly detected in the white population were not recorded in our Senegalese series. Conclusions: The different IGH repertoire we observed in the Senegalese cohort may reflect the diverse genetic and microenvironmental (ie, polymicrobial stimulation) background.

To overcome the drug resistance phenomenon induced by Imatibib (IM), in clinical practice, are often used second generation of tyrosine kinase inhibitors as Nilotinib (NIL); a such potent inhibitor of the BCR/ABL kinase and Dasatinib (DAS), a inhibitor of BCR/ABL kinase, and inhibitor SrC family kinase. In this study we evaluated the in vivo effect of DAS, NIL, and IM on intracellular calcium concentration, oxidative stress, and apoptosis in peripheral blood leukocytes of 45 newly diagnosed patients with chronic myeloid leukaemia (CML-PBM). Our data demonstrated that treatment with DAS and NIL showed an higher modulating potential than IM on intracellular calcium concentration by inhibiting the thapsigargin, a sarcoplasmic/endoplasmic reticulum Ca2+-ATPase (SERCA) inhibitor, and Lithium (Li) an inositol 1,4,5-triphosphate (InsP3) receptor inhibitor activities. Moreover our data demonstrated that NIL and DAS have significantly increased apoptosis more than IM by involving both intracellular calcium signaling as well as oxidative stress. The acquisition of the oxidative stress and calcium channels receptors values data could help the hematologist to modulate and improve the treatment of chronic myeloid leukaemia (CML) pathology.

The concept of unidirectional differentiation of the haematopoietic stem cell has been challenged after recent findings that human B cell progenitors and even mature B cells can be reprogrammed into histiocytic/dendritic cells by altering expression of lineage-associated transcription factors. The conversion of mature B cell lymphomas to Langerhans cell neoplasms is not well documented. Three previous reports have described clonally related follicular lymphoma and Langerhans cell tumours, whereas no case has been published of clonally related marginal zone lymphoma and Langerhans cell sarcoma. We describe the case of a 77-year-old patient who developed a Langerhans cell sarcoma and 6 years later a nodal marginal zone lymphoma. Mutation status examination showed 100 % gene identity to the germline sequence, suggesting direct trans-differentiation or dedifferentiation of the nodal marginal zone lymphoma to the Langerhans cell sarcoma rather than a common progenitor. We found inactivation of paired box 5 (PAX-5) in the lymphoma cells by methylation, along with duplication of part of the long arm of chromosomes 16 and 17 in the sarcoma cells. The absence of PAX-5 could have triggered B cells to differentiate into macrophages and dendritic cells. On the other hand, chromosomal imbalances might have activated genes involved in myeloid lineage maturation, transcription activation and oncogenesis. We hypothesize that this occurred because of previous therapies for nodal marginal zone lymphoma. Better understanding of this phenomenon may help in unravelling the molecular interplay between transcription factors during haematopoietic lineage commitment and may expand the spectrum of clonally related mature B cell neoplasms and Langerhans cell tumours.

Burkitt lymphoma (BL) is an aggressive neoplasm characterized by consistent morphology and phenotype, typical clinical behavior and distinctive molecular profile. The latter is mostly driven by the MYC over-expression associated with the characteristic translocation (8;14) (q24; q32) or with variant lesions. Additional genetic events can contribute to Burkitt Lymphoma pathobiology and retain clinical significance. A pathogenetic role for Epstein-Barr virus infection in Burkitt lymphomagenesis has been suggested; however, the exact function of the virus is largely unknown. In this study, we investigated the molecular profiles (genes and microRNAs) of Epstein-Barr virus-positive and -negative BL, to identify specific patterns relying on the differential expression and role of Epstein-Barr virus-encoded microRNAs. First, we found significant differences in the expression of viral microRNAs and in selected target genes. Among others, we identified LIN28B, CGNL1, GCET2, MRAS, PLCD4, SEL1L, SXX1, and the tyrosine kinases encoding STK10/STK33, all provided with potential pathogenetic significance. GCET2, also validated by immunohistochemistry, appeared to be a useful marker for distinguishing EBV-positive and EBV-negative cases. Further, we provided solid evidences that the EBV-encoded microRNAs (e.g. BART6) significantly mold the transcriptional landscape of Burkitt Lymphoma clones. In conclusion, our data indicated significant differences in the transcriptional profiles of EBV-positive and EBV-negative BL and highlight the role of virus encoded miRNA.

Purpose Lung cancer is strongly associated to tobacco smoking. However, global statistics estimate that in females the proportion of lung cancer cases that is unrelated to tobacco smoking reaches fifty percent, making questionable the etiology of the disease. Materials and methods A never-smoker female with primary EGFR/KRAS/ALK-negative squamous cell carcinoma of the lung and their normal sibswere subjected to a novel integrative "omic" approach using a pedigree-based model for discovering genetic factors leading to cancer in the absence of well-known environmental trigger. A first-stepwhole-exome sequencing on tumor and normal tissue did not identify mutations in known driver genes. Building on the idea of a germline oligogenic origin of lung cancer, we performed whole-exome sequencing of DNA from patients' peripheral blood and their unaffected sibs. Finally, RNA-sequencing analysis in tumoral and matched non-tumoral tissues was carried out in order to investigate the clonal profile and the pathogenic role of the identified variants. Results Filtering for rare variants with Combined Annotation Dependent Depletion (CADD) > 25 and potentially damaging effect, we identified rare/private germline deleterious variants in 11 cancer-associated genes, none ofwhich, except one, sharedwith the healthy sib, pinpointing to a "private" oligogenic germline signature. Noteworthy, among these, two mutated genes, namely ACACA and DEPTOR, turned to be potential targets for therapy because related to known drivers, such as BRCA1 and EGFR. Conclusion In the era of precision medicine, this report emphasizes the importance of an "omic" approach to uncover oligogenic germline signature underlying cancer development and to identify suitable therapeutic targets as well.

Background: Results from the BEVA2007 trial, suggest that the metronomic chemotherapy regimen with dose-fractioned cisplatin and oral etoposide (mPE) +/− bevacizumab, a monoclonal antibody to the vascular endothelial growth factor (VEGF), shows anti-angiogenic and immunological effects and is a safe and active treatment for metastatic non-small cell lung cancer (mNSCLC) patients. We carried out a retrospective analysis aimed to evaluate the antitumor effects of this treatment in a subset of patients with squamous histology. Methods: Retrospective analysis was carried out in a subset of 31 patients with squamous histology enrolled in the study between September 2007 and September 2015. All of the patients received chemotherapy with cisplatin (30 mg/sqm, days 1–3q21) and oral etoposide (50 mg, days 1–15q21) (mPE) and 14 of them also received bevacizumab 5 mg/kg on the day 3q21 (mPEBev regimen). Results: This treatment showed a disease control rate of 71% with a mean progression free survival (PFS) and overall survival (OS) of 13.6 and 17 months respectively. After 4 treatment courses, 6 patients showing a remarkable tumor shrinkage, underwent to radical surgery, attaining a significant advantage in term of survival (P=0.04). Kaplan-Meier and log-rank test identified the longest survival in patients presenting low baseline levels in neutrophil-to-lymphocyte ratio (NLR) (P=0.05), interleukin (IL) 17A (P=0.036), regulatory-T-cells (T reg s) (P=0.020), and activated CD83+ dendritic cells (DCs) (P=0.03). Conclusions: These results suggest that the mPE +/− bevacizumab regimen is feasible and should be tested in comparative trials in advanced squamous-NSCLC (sqNSCLC). Moreover, its immune-biological effects strongly suggest the investigation in sequential combinations with immune check-point inhibitors.

Epstein–Barr virus (EBV) is a gammaherpesvirus linked to a number of lymphoid and epithelial malignancies, including Burkitt lymphoma (BL) in which its frequency ranges from 30% in sporadic cases to 100% in the endemic ones. The possible contribution of EBV to BL pathogenesis is largely unknown. It has been suggested that EBV may be associated with all of the cases, including those diagnosed as EBV negative by a mechanism of hit-and-run. Early during oncogenesis, viral genes are essential for initiating disease. Progressively, viral genome is lost to escape the immune system and host mutations accumulate in proto-oncogenic cell. The main problem with the hit-and-run hypothesis is the lack of evidence in primary tumors. The routine methods applied to detect the virus [i.e., immunohistochemistry and EBV-encoded RNAs (EBER) in situ hybridization (ISH)] have a low specificity and accuracy. The aim of this study was to identify the most suitable method to detect EBV infection in pathology samples by applying conventional and non-conventional methods (i.e., EBV-microRNAs detection and EBV viral load measurement). We investigated a total of 10 cases and we found that all the samples (n = 6) diagnosed as EBV negative by immunohistochemistry and EBER-ISH demonstrated the presence of EBV-microRNAs and EBV genome. This points at the possibility that EBV might have contributed to lymphomagenesis in all our patients, and propose microRNAs detection as the most specific and sensitive tool to recognize EBV vestiges. It is worth noting that our data would have considerable implications for EBV-related diseases control. By using anti-EBV vaccines, one could potentially prevent also some cancers less suspected of a viral origin because of viral genome loss.

Background: In this report we will describe a case of mantle cell lymphoma (MCL) in the conjunctiva and underlying clinical, histologic, immunological and genetic findings jointly with review of current literature.Case presentation: Here we report a case of MCL presenting as bilateral conjunctival masses of a period of over four in a 70-year-old man.Method and results: Histological examination revealed a proliferation of monotonous small-to-medium-sized lymphoid cells with cleaved nuclei in the subconjunctiva. The lymphoid infiltrate expressed CD20, CD5, BCL-2, cyclin D1, and the transcription factor SOX11.Conclusion: We suggest a more focused approach to differential diagnosis of this cancer, as MCL is a more aggressive disease than other entities. Due to the rarity of this lymphoma a multidisciplinary team is essential to achieve the best therapeutic approach.

Objectives: Recent studies using next-generation sequencing (NGS) analysis disclosed the importance of the intrinsic activation of the B-cell receptor (BCR) pathway in the pathogenesis of sporadic Burkitt lymphoma (sBL) due to mutations of TCF3/ID3 genes. Since no definitive data are available on the genetic landscape of endemic Burkitt (eBL), we first assessed the mutation frequency of TCF3/ID3 in eBL compared with sBL and subsequently the somatic hypermutation status of the BCR to answer whether an extrinsic activation of BCR signaling could also be demonstrated in Burkitt lymphoma. Methods: We assessed the mutations of TCF3/ID3 by RNAseq and the BCR status by NGS analysis of the immunoglobulin genes (IGs). Results: We detected mutations of TCF3/ID3 in about 30% of the eBL cases. This rate is significantly lower than that detected in sBL (64%). The NGS analysis of IGs revealed intraclonal diversity, suggesting an active targeted somatic hypermutation process in eBL compared with sBL. Conclusions: These findings support the view that the antigenic pressure plays a key role in the pathogenetic pathways of eBL, which may be partially distinct from those driving sBL development.

Background The oncogenic transcription factor MYC is pathologically activated in many human malignancies. A paradigm for MYC dysregulation is offered by Burkitt lymphoma, where chromosomal translocations leading to Immunoglobulin gene-MYC fusion are the crucial initiating oncogenic events. However, Burkitt lymphoma cases with no detectable MYC rearrangement but maintaining MYC expression have been identified and alternative mechanisms can be involved in MYC dysregulation in these cases. Methods We studied the microRNA profile of MYC translocation-positive and MYC translocation-negative Burkitt lymphoma cases in order to uncover possible differences at the molecular level. Data was validated at the mRNA and protein level by quantitative Real-Time polymerase chain reaction and immunohistochemistry, respectively. Results We identified four microRNAs differentially expressed between the two groups. The impact of these microRNAs on the expression of selected genes was then investigated. Interestingly, in MYC translocation-negative cases we found over-expression of DNA-methyl transferase family members, consistent to hypo-expression of the hsa-miR-29 family. This finding suggests an alternative way for the activation of lymphomagenesis in these cases, based on global changes in methylation landscape, aberrant DNA hypermethylation, lack of epigenetic control on transcription of targeted genes, and increase of genomic instability. In addition, we observed an over-expression of another MYC family gene member, MYCN that may therefore represent a cooperating mechanism of MYC in driving the malignant transformation in those cases lacking an identifiable MYC translocation but expressing the gene at the mRNA and protein levels. Conclusions Collectively, our results showed that MYC translocation-positive and MYC translocation-negative Burkitt lymphoma cases are slightly different in terms of microRNA and gene expression. MYC translocation-negative Burkitt lymphoma, similarly to other aggressive B-cell non Hodgkin’s lymphomas, may represent a model to understand the intricate molecular pathway responsible for MYC dysregulation in cancer. Electronic supplementary material The online version of this article (doi:10.1186/s12885-015-1661-7) contains supplementary material, which is available to authorized users.

Endemic Burkitt lymphoma (eBL) is primarily found in children in equatorial regions and represents the first historical example of a virus-associated human malignancy. Although Epstein-Barr virus (EBV) infection and MYC translocations are hallmarks of the disease, it is unclear whether other factors may contribute to its development. We performed RNA-Seq on 20 eBL cases from Uganda and showed that the mutational and viral landscape of eBL is more complex than previously reported. First, we found the presence of other herpesviridae family members in 8 cases (40%), in particular human herpesvirus 5 and human herpesvirus 8 and confirmed their presence by immunohistochemistry in the adjacent non-neoplastic tissue. Second, we identified a distinct latency program in EBV involving lytic genes in association with TCF3 activity. Third, by comparing the eBL mutational landscape with published data on sporadic Burkitt lymphoma (sBL), we detected lower frequencies of mutations in MYC, ID3, TCF3 and TP53, and a higher frequency of mutation in ARID1A in eBL samples. Recurrent mutations in two genes not previously associated with eBL were identified in 20% of tumors: RHOA and cyclin F (CCNF). We also observed that polyviral samples showed lower numbers of somatic mutations in common altered genes in comparison to sBL specimens, suggesting dual mechanisms of transformation, mutation versus virus driven in sBL and eBL respectively., Author Summary Burkitt lymphoma is endemic in sub-Saharan Africa and affects primarily children of age 4–7 years. Historically, it was one of the first tumors associated with a virus (EBV) and bearing a translocation involving an oncogene, i.e. MYC. There are three distinct clinical variants of Burkitt lymphoma according to the World Health Organization: sporadic, endemic and immunodeficiency-related. Although there has been some recent work on the molecular characterization of sporadic Burkitt lymphomas, little is known about the pathogenesis of endemic cases. In this work, we analyzed 20 samples of RNASeq from Burkitt lymphoma collected in Lacor Hospital (Uganda, Africa) and validated in an extension panel of 73 samples from Uganda and Kenya. We identify the presence in the adjacent non-neoplastic tissue of other herpesviridae family members in 53% of the cases, namely cytomegalovirus (CMV) and Kaposi sarcoma herpesvirus (KSHV). We also demonstrate expression of EBV lytic genes in primary tumor samples and find an inverse association between EBV lytic expression and TCF3 activity. When studying the mutational profile of endemic Burkitt tumors, we find recurrent alterations in genes rarely mutated in sporadic Burkitt lymphomas, i.e. ARID1A, CCNF and RHOA, and lower numbers of mutations in genes previously reported to be commonly mutated in sporadic cases, i.e. MYC, ID3, TCF3, TP53. Together, these results illustrate a distinct genetic and viral profile of endemic Burkitt lymphoma, suggesting a dual mechanism of transformation (mutation versus virus driven in sBL and eBL respectively).

We read with interest the ‘Accepted article’ in Histopathology of Park and colleagues1 that reports novel insight into the early histopathogenesis of immunodeficiency‐associated Burkitt lymphoma (BL), suggesting a possible relationship with monocytoid B cell and speculating on the BL cell of origin. In addition, the paper raises the question of the polymicrobial nature of BL, as cytomegalovirus (CMV) was also detected.

Endemic Burkitt lymphoma (eBL) constitutes the commonest cancer in children in Developing Countries, while the sporadic (sBL) and immunodeficiency associated BL (ID-BL) forms are mainly encountered in Western Countries. The molecular hallmark of three BL variants is the translocation of MYC proto-oncogene to the immunoglobulin-heavy [t(8;14)(q24;q32)] or one of the light chain genes [t(2;8)(p12; q24) and t(8;22)(q24; q11)], leading to constitutive MYC activation. However, additional genetic events contributes to BL pathogenesis, most of which have been studies in sBL only. Here, we performed RNA Sequencing aiming to identify genetic changes possibly cooperating with MYC in the pathogenesis of eBL. We studied by RNA Sequencing (Illumina HiScanSQ) 21 eBL cases, collected at different African Institutions as discovery set. Total RNA was extracted with Trizol and libraries were prepared according to TruSeq RNA sample preparation v2 protocol. Sequence variants were obtained using the SAVI (Statistical Algorithm for Variant Identification) algorithm independently for each sample. Candidate somatic mutations were obtained by eliminating common germline variants and recurrence. To validate single-nucleotide variants (SNVs) we performed Sanger sequencing on these 21 cases. Further, we studied these SNVs by Sequenom Technology and Sanger sequencing on additional 24 eBL cases as validation set. 41 sBL and 8 ID-BL were also considered as controls. We found 66 genes affected by 219 total SNVs with different frequency in 21 samples (range 2-22 for sample). We then focused on genes mutated in at least three samples and predicted to induce somatic protein-changing. We identified 25 genes affected by 172 total SNVs, that were recurrently mutated (min. 3/21 samples; max 11/21 samples). These included genes previously known to be involved in sBL, such as TP53, MYC, ID3, PCBP1 and TCF3 as well as genes involved in other lymphomas such as DDX3X and RHOA. The remaining 18 genes (AGAP6, APBB1IP, ARID1A, ASPSCR1, AVEN, CAD, CCNF, GPATCH4, HERC2, KPNA2, MTBP, MTERFD1, NEK9, NUP133, PARP1, POLQ, SCFD2, TIGD1) were previously not related to BL, and resulted to be involved in several important molecular pathways as cell cycle progression, apoptosis, matrix remodelling, angiogenesis. Sanger sequencing confirmed such SNVs with 100% accuracy in 21 cases of discovery set. Subsequently, we studied them in 24 independent cases of validation set by both Sanger sequencing and by mass spectrometry (Sequenom). We found that most eBL cases carried additional SNVs rather than MYC translocations. Noteworthy, we failed to find these mutations in sBL, confirming the concept that different pathogenetic events may contribute to the pathogenesis of BL subtypes. In conclusion , we discovered new SNVs that might have a significant role in the pathogenesis of eBL. Functional experiments are required to definitely assess their impact. Citation Format: Maria Antonella Laginestra, Francesco Abate, Maryam Etebari, Giulia De Falco, Fabio Fuligni, Maura Rossi, Sakellarios Zairis, Maria Rosaria Sapienza, Anna Gazzola, Claudia Mannu, Federica Melle, Claudio Agostinelli, Mohsen Navari, Cristiana Bellan, Sara Gazaneo, Lucia Mundo, Martin Ogwang, Valeria Calbi, Lorenzo Leoncini, Stefano A. Pileri, Raul Rabadan, Pier Paolo Piccaluga. Identification of single-nucleotide variants by high-throughput RNA sequencing in endemic Burkitt Lymphoma. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5173. doi:10.1158/1538-7445.AM2014-5173