Project description:Vitreoretinal lymphoma is a rare subtype of diffuse large B-cell lymphoma considered a variant of primary central nervous system lymphoma. Its diagnosis requires examination of vitreous fluid, but cytologic differentiation from uveitis remains difficult. Due to its rarity and difficulty in obtaining diagnostic material, little is known about the genetic profile of the disease.
Project description:Vitreoretinal lymphoma (VRL) is a rare subtype of diffuse large B-cell lymphoma (DLBCL) considered a variant of primary central nervous system lymphoma (PCNSL). The diagnosis of VRL requires examination of vitreous fluid, but cytologic differentiation from uveitis remains difficult. Because of its rarity and the difficulty in obtaining diagnostic material, little is known about the genetic profile of VRL. The purpose of our study was to investigate the mutational profile of a large series of primary and secondary VRL. Targeted next-generation sequencing using a custom panel containing the most frequent mutations in PCNSL was performed on 34 vitrectomy samples from 31 patients with VRL and negative controls with uveitis. In a subset of cases, genome-wide copy number alterations (CNAs) were assessed using the OncoScan platform. Mutations in MYD88 (74%), PIM1 (71%), CD79B (55%), IGLL5 (52%), TBL1XR1 (48%), ETV6 (45%), and 9p21/CDKN2A deletions (75%) were the most common alterations, with similar frequencies in primary (n = 16), synchronous (n = 3), or secondary (n = 12) VRL. This mutational spectrum is similar to MYD88mut/CD79Bmut (MCD or cluster 5) DLBCL with activation of Toll-like and B-cell receptor pathways and CDKN2A loss, confirming their close relationship. OncoScan analysis demonstrated a high number of CNAs (mean 18.6 per case). Negative controls lacked mutations or CNAs. Using cell-free DNA of vitreous fluid supernatant, mutations present in cellular DNA were reliably detected in all cases examined. Mutational analysis is a highly sensitive and specific tool for the diagnosis of VRL and can also be applied successfully to cell-free DNA derived from the vitreous.
Project description:FFPE brain biopsy specimens of 64 patients with primary central nervous system lymphoma and 9 patients with secondary central nervous system lymphoma were analyzed in the study. We used the NanoSting nCounter human v3 miRNA assay for characterizing miRNA expression and carried out a detailed differential expression and clustering analysis of samples and miRNAs to look for expression changes associated to primary or secondary origin, cell of origin, mutation status or survival.
Project description:Primary diffuse large B-cell lymphoma (DLBCL) of the central nervous system (PCNSL) is a rare, extranodal lymphoma. Primary vitreo-retinal lymphoma (PVRL) occurs in 15-25% of PCNSL. CNS involvement also occurs in systemic diffuse large B-cell lymphoma, termed secondary central nervous system lymphoma (SCNSL). Despite intensive treatment, patient outcomes are poor when compared to DLBCL without CNS involvement. How and why lymphoma cells home to the CNS and vitreo-retinal compartment remains unknown. In vivo models to study lymphoma cell tropism are urgently needed. We therefore established and characterized 2 primary and 2 secondary patient-derived CNS lymphoma xenograft mouse models using immunohistochemistry, flow cytometry and nucleic acid sequencing technology. In spleen reimplantation experiments, we characterized the dissemination pattern of orthotopic and heterotopic xenografts and performed RNA sequencing to detect differences on the transcriptome level. Moreover, we found that lymphoma cells in PCNSL xenografts home to the eye after intrasplenal implantation in around 60% of cases, similar to PVRL. This in vivo tumor model preserves key features of this rare lymphoma entity and can be used to explore pathways that are critical for CNS and retinal tropism with the goal to find potential new targets for novel therapeutic approaches .
Project description:Primary diffuse large B-cell lymphoma (DLBCL) of the central nervous system (PCNSL) is a rare, extranodal lymphoma. Primary vitreo-retinal lymphoma (PVRL) occurs in 15-25% of PCNSL. CNS involvement also occurs in systemic diffuse large B-cell lymphoma, termed secondary central nervous system lymphoma (SCNSL). Despite intensive treatment, patient outcomes are poor when compared to DLBCL without CNS involvement. How and why lymphoma cells home to the CNS and vitreo-retinal compartment remains unknown. In vivo models to study lymphoma cell tropism are urgently needed. We therefore established and characterized 3 primary and 4 secondary patient-derived CNS lymphoma xenograft mouse models using immunohistochemistry, flow cytometry and nucleic acid sequencing technology. In spleen reimplantation experiments, we characterized the dissemination pattern of orthotopic and heterotopic xenografts and performed RNA sequencing to detect differences on the transcriptome level. Moreover, we found that lymphoma cells in PCNSL xenografts home to the eye after intrasplenal implantation in around 60% of cases, similar to PVRL. This in vivo tumor model preserves key features of this rare lymphoma entity and can be used to explore pathways that are critical for CNS and retinal tropism with the goal to find potential new targets for novel therapeutic approaches .
Project description:The distinction between primary and secondary ovarian tumors may be challenging for pathologists. We performed transcriptomic analysis in order to discriminate between primary ovarian tumors and ovarian metastases after primary breast cancer. We performed genomic analysis on tumor paired samples (breast/ovary) in order to know if genomic profiles could help for the discrimination of primary ovarian tumors and ovarian metastases after primary breast cancer.
Project description:Follicular lymphoma (FL) is characterized by the t(14;18)(q32;q21), frequent numerical chromosomal alterations, and recurrent somatic mutations. However, no genetic studies are available for FL in situ (FLIS), a putative precursor lesion of FL. In this study, we analyzed cases of FLIS without manifest (m)FL, partial involvement by FL (PFL), and paired cases of FLIS and mFL to detect possible early chromosomal imbalances, as well as DNA-methylation patterns of genomic regions of selected genes. We demonstrated that paired FLIS and mFL cases are always clonally related. FLIS and PFL have no or few secondary chromosomal imbalances detectable by copy number arrays and a lower level of gene methylation as compared to mFL. Additionally, EZH2 Tyr641 mutations were detected in a subset of both FLIS and PFL cases. In conclusion, this study provides evidence that FLIS represents a FL precursor lesion of long-lived clonal B-cells carrying the t(14;18) with no or few secondary genetic changes. The earliest secondary genetic alterations detected in FLIS are the EZH2 Tyr641 mutation and low levels of CNAs, as evidence of clonal evolution. Our data suggest that there may be more than one distinct lesion driving the progression from FLIS to manifest lymphoma. DNA from cases, 20 tumor samples (10 in situ Follicular lymphoma, 4 Partial infiltration folliculary lymphoma and 6 manifest FL) were analyzed with Agilent-014693 Human Genome CGH Microarray 244A platform for copy number alterations study. For cases 9-14 paired samples of in situ follicular lymphoma and manifest follicular lymphoma were analyzed. Agilent-014693 Human Genome CGH Microarray 244A arrays were performed according to the manufacturer's directions on DNA extracted from lymph nodes that were hybridized against a normal DNA (pool) of the same gender.
Project description:Sea urchins (echinoids) are common model organisms for research in developmental biology and for their transition from a bilateral larva into their post-metamorphic adult with pentaradial body symmetry. The adult also has a calcareous endoskeleton with a multimetameric pattern of continuously added elements, among them the namesake of this phylum, spines. Nearly all echinoids have both large primary spines, and an associated set of smaller secondary spines.We hypothesize that the secondary spines of the tropical variegated urchin species, Lytechinus variegatus, are morphologically and molecularly distinct structures from primary spines and not just small spines. To test this premise, we examined both spine types using light microscopy, micro-CT imaging, lectin labeling, transcriptomics, and fluorescent in situ hybridization (FISH). Our findings reveal basic similarities between the two types in mineral and cellular anatomy, but with clear differences in growth patterns, genes expressed, and in the location of gene expression within the two types of spines. In particular, secondary spines have non-overlapping, longitudinally concentrated growth bands that lead to a blunt and straight profile, and a distinct transcriptome involving the upregulation in many genes in comparison to the primary spines. Neural, ciliary, and extracellular matrix interacting factors are implicated in the differentially expressed gene (DEG) dataset, including two genes - ONECUT2 and an uncharacterized discoidin- and thrombospondin-containing protein - that show spine type- specific localizations in FISH, and may be of interest to ongoing work in urchin spine patterning.These results demonstrate that primary and secondary spines have overlapping but distinct molecular and biomineralized characteristics, suggesting unique developmental and regenerative mechanisms, and devotion to this spiny dermal phylum.