Search

Az aritmogén cardiomyopathia (ACM) diagnózisa leggyakrabban fizikai terheléssel összefüggő palpitáció vagy syncope, hirtelen szívhalál, illetve jobb kamrai eredetű ritmuszavarok esetén merül fel. A jobb kamrai dominanciájú ACM diagnózisa a 2010-ben módosított Task Force kritériumokon alapul, ami azonban a mindkét kamrát érintő, illetve bal kamrai dominanciájú ACM esetén sokszor nem segíti a diagnózist. Ezekben az esetekben kiemelt szerepe van a kontrasztanyag adásával végzett szív-mágnesesrezonancia- (MR) vizsgálatnak, továbbá a genetikai vizsgálatnak. Két beteg esetét ismertetjük, amikor a klinikai tünetek, vagy a Task Force kritériumok nem voltak ACM-re típusosak. Az 58 éves nőbeteg kivizsgálása szívelégtelenség miatt kezdődött. Szívultrahang-vizsgálat során tág jobb kamra, csökkent jobbkamra-funkció, jelentős tricuspidalis regurgitáció és enyhén emelkedett pulmonalis nyomás igazolódott. Szív-MR-vizsgálattal emelkedett jobb kamrai volumenek, jelentősen csökkent jobb kamrai ejekciós frakció, mindkét kamrát érintő falmozgászavarok és kiterjedt noniszkémiás kontraszthalmozás ábrázolódott, amely alapján felmerült kardiális sarcoidosis, illetve kétkamrás ACM diagnózisa. FDG PET-CT-vizsgálat sarcoidosisra típusos miokardiális dúsulást nem igazolt. Genetikai vizsgálat a Desmoglein 2 gén patogén mutációját igazolta, így kétkamrás érintettségű ACM diagnózisát állítottuk fel. Az 56 éves férfi beteget nyugalomban bekövetkezett eszméletvesztés miatt vizsgáltuk. Koronarográfia ép koszorúsereket igazolt. Telemetriás monitorozással nem tartós kamrai tachycardiát észleltek, elektrofiziológiai vizsgálat során kamrai tachycardiát lehetett kiváltani. Szív-MR-vizsgálat enyhén csökkent bal kamrai ejekciós frakciót, enyhén emelkedett bal kamrai volumeneket igazolt normál jobb kamrai paraméterek mellett. A septumban midmiokardiálisan a T1 súlyozott és zsírelnyomásos felvételek, illetve az alacsony T1-mapping érték alapján zsíros átépülés, továbbá az inferior fal mentén szubepi-midmiokardiális fibrózisnak megfelelő kontraszthalmozás ábrázolódott. Az atípusos MR-kép alapján felmerült bal kamrai ACM, amit a genetikai vizsgálattal felfedezett Desmoplakin gén patogén mutációja igazolt. Eseteink rámutatnak arra, hogy ACM kétkamrás, illetve bal kamrai dominanciájú formáinak diagnózisában kiemelkedő szerepe lehet a szív-MR-nek és a genetikai vizsgálatnak.

A DNS-szekvenálási technológiákban bekövetkezett dinamikus fejlődésnek köszönhetően ismereteink számos kardiológiai betegség, így a cardiomyopathiák, az aritmiaszindrómák és az aortopathiák genetikai alapjainak megértésében is jelentősen bővültek az elmúlt években. A genetikai háttér jobb megértése mellett előrelépések történtek a kezelési lehetőségek terén is, amelyek megkövetelik a pontos diagnózisalkotást és a páciensek rizikóbecslését. A genetikai vizsgálatok integrációja a diagnosztikai eljárások sorába segít a prognózis meghatározásában és a személyre szabott klinikai menedzsment kialakításában. A genetikai vizsgálat célja a betegséget okozó mutáció azonosítása, majd a fokozott rizikójú családtagok preszimptomatikus vagy prediktív tesztelése. A kardiológus kulcsszerepet tölt be azon páciensek kiválasztásában, akik profitálhatnak a genetikai vizsgálatból, amihez elengedhetetlen a genetikai vizsgálatok alapjainak ismerete. Jelen összefoglaló közleményben rövid áttekintést adunk a gyakoribb örökletes kardiovaszkuláris betegségek genetikai hátteréről, a klinikai genetika általános szabályairól, a kardiogenetikai vizsgálat gyakorlati alkalmazásáról és bemutatjuk eddigi vizsgálati eredményeinket ezen betegcsoportokban.

Human reproduction is controlled by ∼2,000 hypothalamic gonadotropin-releasing hormone (GnRH) neurons. Here we report the discovery and characterization of additional 150-200,000 GnRH-synthesizing cells in the human basal ganglia and basal forebrain. Extrahypothalamic GnRH neurons were cholinergic. Though undetectable in adult rodents, the GnRH-GFP transgene was expressed transiently by caudate-putamen cholinergic interneurons in newborn transgenic mice. In slice electrophysiological studies, GnRH inhibited these interneurons via GnRHR1 autoreceptors. Whole-transcriptome analysis of cholinergic interneurons and medium spiny projection neurons laser-microdissected from the human putamen confirmed selective expression of GNRH1 and GNRHR1 autoreceptors in cholinergic cells and uncovered the detailed transcriptome profile and molecular connectome of these two cell types. Higher- order non-reproductive functions regulated by GnRH under physiological conditions in the human basal ganglia and basal forebrain require clarification. GnRH/GnRHR1 signaling as a potential therapeutic target in the treatment of neurodegenerative disorders affecting cholinergic neurocircuitries, including Parkinson’s and Alzheimer’s diseases, needs to be explored.

Összefoglaló. Bevezetés: Az első szaruhártya-bank 1944-es alapítása óta jelentős változásokon ment át. A szaruhártya túlélését számos tényező befolyásolja, így a tárolási mód, melynek a szövet lejárati ideje szerint rövid, közép és hosszú távú módszereit fejlesztették ki. Célkitűzés: Retrospektív vizsgálatunk célja a 2008. január 1. és 2017. december 31. között perforáló és lamelláris keratoplasztika során felhasznált cadaverből és multiorgan donorból származó szaruhártyák túlélésének vizsgálata volt a Semmelweis Egyetem Szemészeti Klinikáján. Módszer: Feljegyeztük a recipiens nemét, életkorát, a műtétet indikáló klinikai diagnózist, a műtét időpontját, a szövettani vizsgálat eredményét, valamint, hogy a beültetett szaruhártya cadaverből vagy multiorgan donorból származott. Meghatároztuk, hogy a recipiens életkora korrelált-e a rekeratoplasztikáig eltelt idővel. Eredmények: 1451 szaruhártya-átültetés történt 1088 beteg (44,6% férfi) 1159 szemén (életkor 62,8 ± 18,5 év), melyek között 938 (64,6%) cadaver és 262 (18,0%) multiorgan donor került felhasználásra, 251 esetben (17,2%) nem állt rendelkezésre adat. A leggyakoribb primer diagnózis a szaruhártya-dekompenzáció volt (325 eset, 28%). A primer keratoplasztikák során felhasznált szaruhártyák 740 esetben (63,8%) cadaverből, 212 esetben (18,2%) multiorgan donorból származtak, 207 esetben (17,8%) nem állt rendelkezésre adat. Első rekeratoplasztika a primer keratoplasztikák közül 217 esetben (18,7%) történt. A leggyakoribb szövettani diagnózis az endothelsejt-degeneráció volt (130 esetben, 60,4%). 146 esetben (67,2%) korábban cadaver, 31 esetben (14,2%) multiorgan donor esetén került sor ismételt műtétre, 40 esetben (18,4%) nem állt rendelkezésre adat. Következtetés: Klinikánkon elsősorban cadaverből származó donorok biztosítják a szaruhártya átültetésekhez szükséges szövetet. Cadaverből vagy multiorgan donorból származó szaruhártyák esetén nem kerül gyakrabban sor rekeratoplasztikára. A szaruhártya-banki tevékenység további fejlesztésével növelhető a donorok túlélése hazánkban. Orv Hetil. 2021; 162(13): 488–496. Summary. Introduction: Corneal banking methods have been changing since the foundation of the first corneal bank in 1944. Corneal graft survival may be affected by several factors, among others the storage method, which may be short-, middle- and long-term storage. Objective: To investigate corneal graft survival at the Department of Ophthalmology, Semmelweis University between 1 January 2008 and 31 December 2017, using cadaver and multiorgan donors for penetrating and lamellar keratoplasty, retrospectively. Method: Recipient sex, age, clinical diagnosis, date of surgery, histological examination results and origin of donors (cadaver or multiorgan donor) were recorded. Correlation between recipient age and time to repeat keratoplasty was also analyzed. Results: There were 1451 keratoplasties in 1159 eyes (age 62.8 ± 18.5 years) of 1088 patients (44.6% male) using 938 (64.6%) cadaver and 262 (18.0%) multiorgan donors, data was not available in 251 (17.2%) cases. There was repeat keratoplasty in 217 patients (18.7% of first keratoplasties). The most common histological diagnosis was endothelial decompensation (130 cases, 60.4%) in these cases. In patients with a first repeat keratoplasty, in 146 cases (67.2%) the first donor originated from cadavers, in 31 cases (14.2%) from multiorgan donors and in 40 cases (18.4%) data were not available. Conclusion: Corneal donors mainly originate from cadavers at our Department. The necessity of repeat keratoplasties does not differ using cadaver or multiorgan donors. With further development of corneal banking, donor survival may be increased in Hungary. Orv Hetil. 2021; 162(13): 488–496.

Aim To analyze the changing trends in penetrating keratoplasty (PKP) indications. Methods This retrospective study included all patients with PKP between 2006 and 2017. Patients were classified using histological diagnoses. Our groups were as the following: pseudophakic or aphakic bullous keratopathy, regraft, acute necrotizing and ulcerative keratitis, keratoconus, Fuchs' dystrophy, corneal dystrophy other than Fuchs', corneal scar, other diagnoses and failed endothelial keratoplasty graft. Additionally, two different time-periods (2006-2012 and 2013-2017) were analysed. Results Totally 1721 histological analyses of 1214 patients were available for review. The diagnoses were pseudophakic or aphakic bullous keratopathy in 487 (28.3%), regraft in 443 (25.7%), acute necrotizing and ulcerative keratitis in 313 (18.2%), corneal scar in 153 (8.9%), keratoconus in 140 (8.1%). Fuchs' dystrophy in 61 (3.5%), corneal dystrophy other than Fuchs' in 46 (2.7%), other diagnoses in 44 (2.6%) and failed endothelial keratoplasty graft in 34 (2.0%) cases. From the first to the second analysed time-period, incidence of acute necrotizing and ulcerative keratitis, corneal scar, Fuchs' dystrophy increased (P≤0.032 for all) and incidence of keratoconus significantly decreased (P=0.015). Conclusion Pseudophakic or aphakic bullous keratopathy is the leading indication for PKP, followed by regraft and acute necrotizing and ulcerative keratitis.

Follicular lymphoma (FL) is an indolent, B-cell, non-Hodgkin’s lymphoma with varying cytological appearance and clinical behavior. The genetic hallmark of FL is the t(14;18) translocation, and as a germinal center derived entity it is also characterized by somatic hypermutation of the immunoglobulin heavy chain (IgH) gene. In an attempt to correlate this molecular signature with the cytological grading of FL, we have analyzed the IgH variable (IgVH), regions in all cytological grades of FL. Four FL cases showing t(14;18) translocation were classified into grade I-III categories according to the current WHO guidelines. The IgVH gene segments were PCR-amplified, sequenced, and compared to their respective germline IgVH sequences. The neoplastic cells of grade I and II FLs revealed clonally related, but highly divergent IgVH gene sequences indicating the ongoing nature of somatic hypermutation. Grade III FL also showed extensive presence of somatic hypermutation, but these mutations were not associated with intraclonal divergence. Thus, these results suggest that grade I-II and grade III FL may represent different biological entities. The presence of ongoing somatic hypermutation of IgVH sequences in grade I and II FLs is compatible with direct follicular origin of these tumor cells, contrasting the homogenous, stable clones of grade III FL resembling a post-follicular stage of B-cell development. Our findings demonstrate that contrary to the three tiered cytological grading, molecular features of IgH genes classify FL into two distinct subcategories. These studies also suggest that with progression FL gains post-follicular–like molecular features and becomes independent of the germinal center microenvironment. Electronic supplementary material The online version of this article (10.1007/s12253-020-00843-x) contains supplementary material, which is available to authorized users.

Absztrakt: Bevezetés: A hepatitis C-vírus (HCV) krónikus májgyulladáshoz, májcirrhosishoz, májrákhoz vezethet. A Flaviviridae csoportba tartozó RNS vírus nemcsak hepatotrop, de lymphotrop tulajdonsággal is rendelkezik. Számos extrahepatikus manifesztációja között jelentős a lymphoproliferatív eltérés. A főként B-sejtes betegségek közül leggyakoribb az alacsony malignitású marginalis zóna lymphoma, a diffúz nagy B-sejtes lymphoma, valamint a follicularis lymphoma. Beteg: A hypertoniás, visszérműtéten átesett 54 éves férfi beteg thrombopeniájának, indirekt, Coombs-pozitív hyperbilirubunaemiájának és hepatosplenomegaliájának hátterében HCV-infekció talaján kialakult Child B stádiumú májcirrhosis igazolódott. Az inhomogén szerkezetű, megnagyobbodott, lobulált felszínű májban körülírt eltérés nem látszott. A portalis keringés megtartott volt. A máj fokozott keménysége (26 kPa, IQR/med. 18%) F4 cirrhosisra utalt. A homogén szerkezetű lépet jelentősen nagyobbnak (20×9 cm) mértük. A perifériás vérkenet alapján lymphoma gyanúja merült fel, amit a crista-biopsia eredménye megerősített, CD5/CD10-negatív marginális zóna lymphomát (MZL) diagnosztizáltunk. A fenti májbetegségnek és a HCV 1b genotípusnak megfelelően, sofosbuvir/ledipasvir direkt antivirális kezelést indítottunk. A 12 hetes kezelés tartós vírusmentességet eredményezett. Mind a májbetegség, mind a lymphoma tünetei mérséklődtek, a beteg testsúlya nőtt, fáradékonysága megszűnt. Megbeszélés: Az irodalomból is ismert, hogy a krónikus C hepatitisben a B-sejtes lymphomák előfordulása gyakoribb. Az antiviralis kezelés hatására lymphoma javulását is leírták, esetünkben a társuló immunhaemolysis mértékének csökkenését észleltük. Lymphomaspecifikus kezelés jelenleg nem szükséges, a beteg tünetmentes és stabil, progresszió esetén rituximab monoterápia jön szóba. Következtetés: A fenti eset példa a HCV-pozitív betegekben előforduló B-sejtes lymphomára. Bár az irodalomból ismert, hogy a hepatitis C-vírus eradikációjával a B-sejtes non-Hodgkin-lymphoma regrediálhat, esetünkben az eddig eltelt vírusmentes időszakban ezt még nem észleltük, igaz, hogy progressziót sem.

The oral, highly selective Bcl2 inhibitor venetoclax has substantially improved the therapeutic landscape of chronic lymphocytic leukemia (CLL). Despite the remarkable response rates in patients with relapsed/refractory (R/R) disease, acquired resistance is the leading cause of treatment failure, with somatic BCL2 mutations being the predominant genetic drivers underpinning venetoclax resistance. To assess the correlation between disease progression and the most common BCL2 mutations G101V and D103Y, sensitive (10−4) screening for the most common BCL2 mutations G101V and D103Y was performed in 67 R/R CLL patients during venetoclax single-agent or venetoclax–rituximab combination therapy. With a median follow-up time of 23 months, BCL2 G101V and D103Y were detected in 10.4% (7/67) and 11.9% (8/67) of the cases, respectively, with four patients harboring both resistance mutations. Ten out of eleven patients carrying BCL2 G101V and/or D103Y experienced relapse during the follow-up period, representing 43.5% of the cases (10/23) showing clinical signs of disease progression. All BCL2 G101V or D103Y variants were detected in patients receiving venetoclax as a continuous single-agent treatment while these mutations were not observed during or after fixed-duration venetoclax therapy. Targeted ultra-deep sequencing of BCL2 uncovered three additional variants in four patient samples obtained at relapse, suggesting convergent evolution and implying a cooperating role of BCL2 mutations in driving venetoclax resistance. This cohort is the largest R/R CLL patient population reported to date in which BCL2 resistance mutations were investigated. Our study demonstrates the feasibility and clinical value of sensitive screening for BCL2 resistance mutations in R/R CLL.

Plasma cell myeloma (multiple myeloma [MM]) is a malignant neoplasm originating from the plasma cells. Besides other methods, flow cytometric analysis of the patient's bone marrow aspirate has an important role in the diagnosis and also in the response assessment. Since the cell surface markers, used for identifying abnormal plasma cells, are expressed diversely and the treatment can also alter the phenotype of the plasma cells, there is an increasing demand for new plasma cell markers. VS38c is a monoclonal antibody that recognizes the CLIMP-63 protein in the membrane of the endoplasmic reticulum. CLIMP-63 is known to be expressed at high levels in normal and pathologic plasma cells in the bone marrow, thus VS38c antibody can be used to identify them. Although VS38c staining of plasma cells is reported to be constant and strong even in myeloma, we were wondering whether sample preparation can affect the staining. We have investigated the effect of different permeabilization agents and washing of the cells on the quality of the VS38c staining and found that in many cases the staining is inadequate to identify the plasma cells. We measured the VS38c staining of the bone marrow aspirates of 196 MM patients and observed that almost all cases showed bright staining with VS38c. However, permeabilization with mild detergent resulted in the appearance of a significant VS38cdim subpopulation, which showed increased sensitivity to mechanical stress (centrifugation). Our results indicate that VS38cdim MM cells can appear due to the improper permeabilization of the endoplasmic reticulum and this finding raises the possibility of the existence of a plasma cell subpopulation with different membrane properties. The significance of this population is unclear yet, but these cells can be easily missed with VS38c staining and can be lost due to centrifugation-induced lysis during sample preparation.

In the pathogenesis of chronic lymphocytic leukemia (CLL) the microenvironment plays an important role, as it produces survival signals and mediates drug resistance. Lenalidomide, which has immunomodulatory effect, can enhance the activation of T-, NK-cells and endothelial cells, however there are no data available whether it can modulate bone marrow stromal cells (BMSCs). In our study, we investigated the effects of lenalidomide on BMSCs and CLL cells. CLL cells were cultured alone or with BMSCs and were treated with lenalidomide. Apoptosis, immunophenotype, and cytokine secretion of BMSCs and CLL cells were determined by flow cytometry. Lenalidomide slightly increased the apoptosis of CLL cells and abrogated the anti-apoptotic effect of BMSCs on CLL cells. Lenalidomide treatment decreased the expression of antigens on CLL cells, which mediate the interactions with the microenvironment. Interestingly, lenalidomide enhanced the expression of IRF4 and the co-stimulatory molecule CD86. The secretion of several cytokines was not changed significantly by lenalidomide. CD49d-negative CLL cases were more sensitive to lenalidomide treatment. Our results suggest that lenalidomide has a limited effect on BMSCs, but it renders CLL cells more immunogenic and unresponsive to survival signals provided by BMSCs.

Central nervous system (CNS) lymphoma is a rare and aggressive non-Hodgkin lymphoma that might arise in the CNS (primary CNS lymphoma, PCNSL) or disseminates from a systemic lymphoma to the CNS (secondary CNS lymphoma, SCNSL). Dysregulated expression of microRNAs (miRNAs) is associated with various pathological processes and miRNA expression patterns may have diagnostic, prognostic and therapeutic implications. However, miRNA expression is understudied in CNS lymphomas. Here, we performed expression analysis of 798 miRNAs in 73 CNS lymphoma samples using the NanoString platform, followed by a detailed statistical analysis to identify potential novel biomarkers characterizing subgroups and to examine differences based on their primary and secondary nature, molecular subtype, mutational patterns and survival. We describe the general expression patterns of miRNAs across CNS lymphoma samples and identified 31 differentially expressed miRNAs between primary and secondary groups. Additionally, we identified 7 more miRNAs associated with a molecular subtype and 25 associated with mutation status. Using unsupervised clustering methods, we defined a small but distinct primary CNS lymphoma subgroup, with characteristically different expression patterns compared to the rest of the cases. Finally, we identified differentially regulated pathways in the above comparisons and assessed the utility of miRNA expression patterns in predicting survival. Our study identifies a novel CNS lymphoma subgroup defined by distinct miRNAs, proves the importance of specific miRNAs and pathways in their pathogenesis, and provides the basis for future research.

The Bruton's tyrosine kinase (BTK) inhibitor ibrutinib has revolutionised the therapeutic landscape of chronic lymphocytic leukaemia (CLL). Acquired mutations emerging at position C481 in the BTK tyrosine kinase domain are the predominant genetic alterations associated with secondary ibrutinib resistance. To assess the correlation between disease progression, and the emergence and temporal dynamics of the most common resistance mutation BTK

The Bruton's tyrosine kinase (BTK) inhibitor ibrutinib has revolutionised the therapeutic landscape of chronic lymphocytic leukaemia (CLL). Acquired mutations emerging at position C481 in the BTK tyrosine kinase domain are the predominant genetic alterations associated with secondary ibrutinib resistance. To assess the correlation between disease progression, and the emergence and temporal dynamics of the most common resistance mutation BTKC481S , sensitive (10-4 ) time-resolved screening was performed in 83 relapsed/refractory CLL patients during single-agent ibrutinib treatment. With a median follow-up time of 40 months, BTKC481S was detected in 48·2% (40/83) of the patients, with 80·0% (32/40) of them showing disease progression during the examined period. In these 32 cases, representing 72·7% (32/44) of all patients experiencing relapse, emergence of the BTKC481S mutation preceded the symptoms of clinical relapse with a median of nine months. Subsequent Bcl-2 inhibition therapy applied in 28/32 patients harbouring BTKC481S and progressing on ibrutinib conferred clinical and molecular remission across the patients. Our study demonstrates the clinical value of sensitive BTKC481S monitoring with the largest longitudinally analysed real-world patient cohort reported to date and validates the feasibility of an early prediction of relapse in the majority of ibrutinib-treated relapsed/refractory CLL patients experiencing disease progression.

Richter syndrome (RS) represents the development of high-grade lymphoma in patients with chronic lymphocytic leukaemia (CLL) or small lymphocytic lymphoma (SLL) and presents a diagnostic and therapeutic challenge with an adverse prognosis. The genetic background and morphology of RS in CLL patients treated with chemoimmunotherapy is extensively characterised; however, our knowledge about RS in patients treated with targeted oral therapies should be extended. To understand the morphologic and molecular changes leading to RS in CLL patients treated with the Bruton's tyrosine kinase inhibitor, ibrutinib, and the BCL2 inhibitor, venetoclax, sequential samples from six CLL/SLL patients undergoing RS were collected in both the CLL and RS phases. A detailed immunophenotypic analysis of formalin-fixed, paraffin-embedded tissue specimens of RS phase was performed, followed by extensive molecular characterisation of CLL and RS samples, including the immunoglobulin heavy chain gene (IGH) rearrangement, TP53 mutations, drug-induced resistance mutations in BTK and BCL2 genes and various copy number changes and point mutations detectable with multiplex ligation-dependent probe amplification (MLPA). Rare, non-diffuse large B-cell lymphoma phenotypes of RS were observed in 3/6 cases, including plasmablastic lymphoma and a transitory entity between diffuse large B-cell lymphoma and classical Hodgkin lymphoma. The majority of cases were clonally related and harboured an unmutated variable region of the immunoglobulin heavy chain gene. Abnormalities affecting the TP53 gene occurred in all patients, and every patient carried at least one genetic abnormality conferring susceptibility to RS. In the background of RS, 2/5 patients treated with ibrutinib showed a BTK C481S resistance mutation. One patient developed a BCL2 G101V mutation leading to venetoclax resistance and RS. In conclusion, our findings contribute to better understanding of RS pathogenesis in the era of targeted oral therapies. Rare phenotypic variants of RS do occur under the treatment of ibrutinib or venetoclax, and genetic factors leading to RS are similar to those identified in patients treated with chemoimmunotherapy. To our best knowledge, we have reported the first BCL2 G101V mutation in an RS patient treated with venetoclax.

Összefoglaló. Bevezetés: Az első szaruhártya-bank 1944-es alapítása óta jelentős változásokon ment át. A szaruhártya túlélését számos tényező befolyásolja, így a tárolási mód, melynek a szövet lejárati ideje szerint rövid, közép és hosszú távú módszereit fejlesztették ki. Célkitűzés: Retrospektív vizsgálatunk célja a 2008. január 1. és 2017. december 31. között perforáló és lamelláris keratoplasztika során felhasznált cadaverből és multiorgan donorból származó szaruhártyák túlélésének vizsgálata volt a Semmelweis Egyetem Szemészeti Klinikáján. Módszer: Feljegyeztük a recipiens nemét, életkorát, a műtétet indikáló klinikai diagnózist, a műtét időpontját, a szövettani vizsgálat eredményét, valamint, hogy a beültetett szaruhártya cadaverből vagy multiorgan donorból származott. Meghatároztuk, hogy a recipiens életkora korrelált-e a rekeratoplasztikáig eltelt idővel. Eredmények: 1451 szaruhártya-átültetés történt 1088 beteg (44,6% férfi) 1159 szemén (életkor 62,8 ± 18,5 év), melyek között 938 (64,6%) cadaver és 262 (18,0%) multiorgan donor került felhasználásra, 251 esetben (17,2%) nem állt rendelkezésre adat. A leggyakoribb primer diagnózis a szaruhártya-dekompenzáció volt (325 eset, 28%). A primer keratoplasztikák során felhasznált szaruhártyák 740 esetben (63,8%) cadaverből, 212 esetben (18,2%) multiorgan donorból származtak, 207 esetben (17,8%) nem állt rendelkezésre adat. Első rekeratoplasztika a primer keratoplasztikák közül 217 esetben (18,7%) történt. A leggyakoribb szövettani diagnózis az endothelsejt-degeneráció volt (130 esetben, 60,4%). 146 esetben (67,2%) korábban cadaver, 31 esetben (14,2%) multiorgan donor esetén került sor ismételt műtétre, 40 esetben (18,4%) nem állt rendelkezésre adat. Következtetés: Klinikánkon elsősorban cadaverből származó donorok biztosítják a szaruhártya átültetésekhez szükséges szövetet. Cadaverből vagy multiorgan donorból származó szaruhártyák esetén nem kerül gyakrabban sor rekeratoplasztikára. A szaruhártya-banki tevékenység további fejlesztésével növelhető a donorok túlélése hazánkban. Orv Hetil. 2021; 162(13): 488-496.Corneal banking methods have been changing since the foundation of the first corneal bank in 1944. Corneal graft survival may be affected by several factors, among others the storage method, which may be short-, middle- and long-term storage.To investigate corneal graft survival at the Department of Ophthalmology, Semmelweis University between 1 January 2008 and 31 December 2017, using cadaver and multiorgan donors for penetrating and lamellar keratoplasty, retrospectively.Recipient sex, age, clinical diagnosis, date of surgery, histological examination results and origin of donors (cadaver or multiorgan donor) were recorded. Correlation between recipient age and time to repeat keratoplasty was also analyzed.There were 1451 keratoplasties in 1159 eyes (age 62.8 ± 18.5 years) of 1088 patients (44.6% male) using 938 (64.6%) cadaver and 262 (18.0%) multiorgan donors, data was not available in 251 (17.2%) cases. There was repeat keratoplasty in 217 patients (18.7% of first keratoplasties). The most common histological diagnosis was endothelial decompensation (130 cases, 60.4%) in these cases. In patients with a first repeat keratoplasty, in 146 cases (67.2%) the first donor originated from cadavers, in 31 cases (14.2%) from multiorgan donors and in 40 cases (18.4%) data were not available.Corneal donors mainly originate from cadavers at our Department. The necessity of repeat keratoplasties does not differ using cadaver or multiorgan donors. With further development of corneal banking, donor survival may be increased in Hungary. Orv Hetil. 2021; 162(13): 488-496.

Recent advances in molecular technologies enable sensitive and quantitative assessment of circulating tumor DNA, offering a noninvasive disease monitoring tool for patients with malignant disorders. Here, we demonstrated on four follicular lymphoma cases that circulating tumor DNA based EZH2 mutation analysis performed by a highly sensitive droplet digital PCR method may be a valuable treatment monitoring approach in EZH2 mutant follicular lymphoma. EZH2 variant allele frequencies changed in parallel with the volume of metabolically active tumor sites observed on 18F-fluorodeoxyglucose positron emission tomography combined with computer tomography (PET-CT) scans. Variant allele frequencies of EZH2 mutations decreased or were eliminated rapidly upon successful treatment, with treatment failure being associated with elevated EZH2 variant allele frequencies. We also demonstrated spatial heterogeneity in a patient with two different EZH2 mutations in distinct anatomical sites, with both mutations simultaneously detected in the liquid biopsy specimen. In summary, circulating tumor DNA based EZH2 mutation analysis offers a rapid, real-time, radiation-free monitoring tool for sensitive detection of EZH2 mutations deriving from different anatomical sites in follicular lymphoma patients receiving immunochemotherapy.

Acute lymphoblastic leukemia is the most common pediatric cancer characterized by a heterogeneous genomic landscape with copy number aberrations occurring at various stages of pathogenesis, disease progression, and treatment resistance. In this study, disease-relevant copy number aberrations were profiled in bone marrow samples of 91 children with B- or T-cell precursor acute lymphoblastic leukemia using digital multiplex ligation-dependent probe amplification (digitalMLPA(TM)). Whole chromosome gains and losses, subchromosomal copy number aberrations, as well as unbalanced alterations conferring intrachromosomal gene fusions were simultaneously identified with results available within 36 hours. Aberrations were observed in 96% of diagnostic patient samples, and increased numbers of copy number aberrations were detected at the time of relapse as compared with diagnosis. Comparative scrutiny of 24 matching diagnostic and relapse samples from 11 patients revealed three different patterns of clonal relationships with (i) one patient displaying identical copy number aberration profiles at diagnosis and relapse, (ii) six patients showing clonal evolution with all lesions detected at diagnosis being present at relapse, and (iii) four patients displaying conserved as well as lost or gained copy number aberrations at the time of relapse, suggestive of the presence of a common ancestral cell compartment giving rise to clinically manifest leukemia at different time points during the disease course. A newly introduced risk classifier combining cytogenetic data with digitalMLPA(TM)-based copy number aberration profiles allowed for the determination of four genetic subgroups of B-cell precursor acute lymphoblastic leukemia with distinct event-free survival rates. DigitalMLPA(TM) provides fast, robust, and highly optimized copy number aberration profiling for the genomic characterization of acute lymphoblastic leukemia samples, facilitates the decipherment of the clonal origin of relapse and provides highly relevant information for clinical prognosis assessment.

Micro-environment plays important role in the pathogenesis of CLL by providing protective niche for CLL cells. Several molecules play important role in communication between CLL cells and immune cells like CD86.Some of the data suggest that CLL patients with high CD86 level need earlier treatments and cells with higher CD86 expression has higher proliferation rate but the role of CD86 in the survival and proliferation of CLL cells is unclear. We investigated the effect of CD86 expression to CLL cells in 50 peripheral blood and 15 lymph node biopsy samples from CLL patients. Our results showed that the expressions of CD86 increased significantly after 7 day culturing in medium, or in the presence of bone marrow stromal cells (BMSCs). We found positive correlation between CD86 and CD23 expression (p

CD49d and CXCR4 are key determinants of interactions between chronic lymphocytic leukemia (CLL) tumor cells and their microenvironment. In this study, we investigated the effect of CD49d and CXCR4 expressions on survival of CLL cells. Primary CLL cells were cultured with CD49d ligand, VCAM-1, or bone marrow stromal cells (BMSCs); then, apoptosis and immunophenotype analyses were performed. VCAM-1 treatment could not induce direct apoptosis protection or immunophenotype change on the CD49d-expressing CLL cells, but resulted in actin reorganization. The BMSC-induced apoptosis protection was independent from the presence of CD49d expression of CLL cells, but showed an inverse correlation with their CXCR4 expression level. We suppose that CD49d contributes to enhanced survival of leukemic cells by mediating migration to the protective microenvironment, not by direct prevention of apoptosis. Moreover, CLL cells with low CXCR4 expression represent a subpopulation that is more dependent on the microenvironmental stimuli for survival, and show increased "death by neglect" when separated from the supportive niche.

Primary cutaneous follicle center lymphoma (PCFCL) is an indolent variant of follicular lymphoma (FL) with limited information available on the genetic background of the disease. The genetic hallmark of nodal FL, the t(14;18) translocation, affecting the BCL2 gene, is rare in PCFCL. Loss of 1p36, the most common secondary chromosomal abnormality in nodal FL, has been recently reported in 16.7% of PCFCL cases. In order to further characterize PCFCL, 21 cases were analyzed using interphase fluorescence in situ hybridization with BCL2 break apart and 1p36/1q25 dual color probes. Sanger sequencing was used to investigate TNFRSF14 and EZH2 mutations and immunohistochemistry to assess BCL2, EZH2 protein expressions. 1p36 deletion occurred in 22% (5/21), BCL2 gene break in 10% (2/20) of the PCFCL cases. Mutations of the candidate tumor suppressor gene of the 1p36 region, TNFRSF14 mutations were detected in 4/17 (23.5%) cases with 2 cases presenting with concurrent 1p36 deletion. EZH2 hotspot mutations at Y641, A682, and A692 were not found. High EZH2 protein expression associated with a BCL2 negative phenotype was observed in 43% (9/21) of the cases. BCL2 gene break or 1p36 deletion did not impact the prognosis; however, they showed association with advanced stages at diagnosis (p = 0.016) and a tendency with shorter event free survival (p = 0.052). In conclusion, 1p36 deletion co-occurs with acquired TNFRSF14 mutations, suggesting a role of this tumor suppressor gene in the development of a subgroup of PCFCL. High EZH2 protein expression associated with BCL2 negative phenotype is common and might represent an ideal therapeutic target.

Background Philadelphia negative myeloproliferative neoplasms (MPNs) are characterized by frequent mutations of driver genes including JAK2, CALR and MPL. While the influence of JAK2 V617F mutant allele burden on the clinical phenotype of MPN patients is well-described, the impact of CALR mutant allele burden on clinical features needs further investigation. Patients and methods Quantitative assessment of JAK2 and CALR mutations was performed on diagnostic DNA samples from 425 essential thrombocythemia (ET) and 227 primary myelofibrosis patients using real-time quantitative PCR and fragment length analysis. Characterization of CALR mutations and detection of MPL mutations were performed by Sanger sequencing. Results Twelve novel CALR mutations have been identified. ET patients with CALRmut load exceeding the median value exhibited lower hemoglobin values (12.0 vs. 13.6 g/dL), higher LDH levels (510 vs. 351 IU/L) and higher rate of myelofibrotic transformation (19% vs. 5%). The CALRmut load was higher among ET patients presenting with splenomegaly compared to those without splenomegaly (50.0% vs. 43.5%). Conclusion Our study confirms the clinical significance of driver mutational status and JAK2mut load in MPNs; in addition, unravels a novel clinical association between high CALRmut load and a more proliferative phenotype in ET.

Kisspeptin (KP) synthesizing neurons of the hypothalamic infundibular region are critically involved in the central regulation of fertility; these cells regulate pulsatile gonadotropin-releasing hormone (GnRH) secretion and mediate sex steroid feedback signals to GnRH neurons. Fine structural analysis of the human KP system is complicated by the use of post mortem tissues. To gain better insight into the neuroanatomy of the somato-dendritic cellular compartment, we introduced the diolistic labeling of immunohistochemically identified KP neurons using a gene gun loaded with the lipophilic dye, DiI. Confocal microscopic studies of primary dendrites in 100-µm-thick tissue sections established that 79.3% of KP cells were bipolar, 14.1% were tripolar, and 6.6% were unipolar. Primary dendrites branched sparsely, contained numerous appendages (9.1 ± 1.1 spines/100 µm dendrite), and received rich innervation from GABAergic, glutamatergic, and KP-containing terminals. KP neuron synaptology was analyzed with immunoelectron microscopy on perfusion-fixed specimens. KP axons established frequent contacts and classical synapses on unlabeled, and on KP-immunoreactive somata, dendrites, and spines. Synapses were asymmetric and the presynaptic structures contained round and regular synaptic vesicles, in addition to dense-core granules. Although immunofluorescent studies failed to detect vesicular glutamate transporter isoforms in KP axons, ultrastructural characteristics of synaptic terminals suggested use of glutamatergic, in addition to peptidergic, neurotransmission. In summary, immunofluorescent and DiI labeling of KP neurons in thick hypothalamic sections and immunoelectron microscopic studies of KP-immunoreactive neurons in brains perfusion-fixed shortly post mortem allowed us to identify previously unexplored fine structural features of KP neurons in the mediobasal hypothalamus of humans.

Although genetic predisposition to haematological malignancies has long been known, genetic testing is not yet the part of the routine diagnostics. In the last ten years, next generation sequencing based studies identified novel germline mutations in the background of familial aggregation of certain haematologic disorders including myelodysplastic syndromes (MDS) and acute myeloid leukaemia (AML). This is supported by the fact that the myeloid neoplasms with genetic predisposition represent a new category in the revised 2016 World Health Organization classification. According to the new classification, these disorders are subdivided based on the clinical and genetic features, including myeloid neoplasms with germline predisposition alone, or with pre-existing platelet disorder, cytopaenias or other organ failures. The predisposing genetic factors include mutations in the RUNX1, CEBPA, GATA2, ANKRD26, ETV6, DDX41, TERC or TERT and SRP72 genes. The genes affected in these syndromes are important regulators of haemopoiesis and are frequently implicated in leukaemogenesis, providing deeper insight into the understanding of normal and malignant haemopoiesis. Despite the growing knowledge of germline predisposing events in the background of familial myeloid malignancies, the germline genetic component is still unknown in a subset of these pedigrees. Here, we present the first study of inherited myeloid malignancies in Hungary. We identified three families with apparent clustering of myeloid malignancies with nine affected individuals across these pedigrees. All tested individuals were negative for CEBPA, GATA2, RUNX1, ANKRD26, ETV6, DDX41, TERC or TERT and SRP72 mutations, suggesting the presence of so far unidentified predisposing mutations.

Primary central nervous system lymphomas (PCNSL) are aggressive non-Hodgkin lymphomas affecting the central nervous system (CNS). Although immunophenotyping studies suggested an uniform activated B-cell (ABC) origin, more recently a spectrum of ABC and germinal center B-cell (GC) cases has been proposed, with the molecular subtypes of PCNSL still being a matter of debate. With the emergence of novel therapies demonstrating different efficacy between the ABC and GC patient groups, precise assignment of molecular subtype is becoming indispensable. To determine the molecular subtype of 77 PCNSL and 17 secondary CNS lymphoma patients, we used the NanoString Lymphoma Subtyping Test (LST), a gene expression-based assay representing a more accurate technique of subtyping compared with standard immunohistochemical (IHC) algorithms. Mutational landscapes of 14 target genes were determined using ultra-deep next-generation sequencing. Using the LST-assay, a significantly lower proportion (80% vs 95%) of PCNSL cases displayed ABC phenotype compared with the IHC-based characterization. The most frequently mutated genes included MYD88, PIM1, and KMT2D. In summary, we successfully applied the LST-assay for molecular classification of PCNSL, reporting higher proportion of cases with GC phenotype compared with IHC analyses, leading to a more precise patient stratification potentially applicable in the diagnostic algorithm of PCNSL.

Multiple myeloma (MM) is a clonal B-cell malignancy characterized by the accumulation of monoclonal plasma cells (PCs) in the bone marrow and other tissues. Although there are several new therapies, MM remains fatal. The interaction between MM cells and the bone marrow microenvironment promotes drug resistance and cancer cells survival. In our present work, we compared the antigen expression pattern of normal and pathological PCs and investigated the possible connections between various surface receptors, adhesion molecules, and recurrent genetic aberrations. We showed that the expression of CD29, CD27, and CD81 is lower in MM cells than in normal PCs. We found correlation of chromosome 11 hyperdiploidity and the decrease of CD27 expression. We demonstrated that MM cells with CD20 positivity also have CD28 expression. Multiple myeloma patients with active CD29 showed better response to treatment. Our results suggest that these changes may result in an alteration of the interaction between stromal cell and MM cell facilitating cell survival and the development of a more aggressive and resistant phenotype.

// Sougat Misra 1 , Arun Kumar Selvam 1 , Marita Wallenberg 1 , Aditya Ambati 2,3 , Andras Matolcsy 4 , Isabelle Magalhaes 5 , Gilbert Lauter 6 and Mikael Bjornstedt 1 1 Department of Laboratory Medicine, Division of Pathology F46, Karolinska Institutet, Karolinska University Hospital Huddinge, Stockholm, Sweden 2 Therapeutic Immunology Unit, Department of Laboratory Medicine, Karolinska Institutet, Stockholm, Sweden 3 Centre for Allogeneic Stem Cell Transplantation (CAST), Karolinska University Hospital, Stockholm, Sweden 4 1st Department of Pathology and Experimental Cancer Research, Semmelweis University, Faculty of Medicine, Budapest, Ullői ut, Hungary 5 Department of Oncology-Pathology, Karolinska Institutet, Stockholm, Sweden 6 Department of Biosciences and Nutrition, NOVUM, Karolinska Institutet, Huddinge, Sweden Correspondence to: Sougat Misra, email: // Mikael Bjornstedt, email: // Keywords : acute myeloid leukemia, selenite, all-trans retinoic acid, differentiation, PML/RARA Received : August 04, 2016 Accepted : September 29, 2016 Published : October 08, 2016 Abstract Selective targeting of the PML/RARα oncoprotein demonstrates a successful molecular targeted therapy in acute promyelocytic leukemia (APL) with a typical t(15:17) chromosomal translocation. The zinc-thiolate coordination is critical for structural stability of zinc finger proteins, including the PML moiety of PML/RARα. Based on the known interaction of redox-active selenium compounds with thiolate ligands of zinc, we herein have investigated the abrogatory effects of selenite alone or in combination with all- trans retinoic acid on PML/RARα and the possible effects on differentiation in these cells. At pharmacological concentrations, selenite inhibited the proliferation and survival of APL originated NB4 cells. In combination with ATRA, it potentiated the differentiation of NB4 cells without any differentiating effects of its own as a single agent. Concordant with our hypothesis, PML/RARα oncoprotein expression was completely abrogated by selenite. Increased expression of RAR, PU.1 and FOXO3A transcription factors in the combined treatment suggested the plausible basis for increased differentiation in these cells. We show that selenite at clinically achievable dose targets PML/RARα oncoprotein for degradation and potentiates differentiation of promyelocytic leukemic cells in combination with ATRA. The present investigation reveals the hitherto unknown potential of selenite in targeted abrogation of PML/RARα in APL cells with prospective therapeutic value.

Lymphomatoid papulosis (LyP) belongs to CD30+ lymphoproliferative disorders with indolent clinical course. Classic histological subtypes, A, B and C are characterized by the CD4+ phenotype, while CD8+ variants, most commonly classified as type D, were reported in recent years. We present 14 cases of CD8+ LyP. In all patients, self-resolving or treatment-sensitive papules were observed. Of 14 cases 7 produced results with typical microscopic features of LyP type D mimicking primary cutaneous aggressive epidermotropic CD8+ T-cell lymphoma. The infiltration pattern in 4 of 14 cases were consistent with classic LyP type B, without CD30 expression in two cases, resembling mycosis fungoides (MF). The morphology of 2 of 14 cases shared a certain consistency with classic type A and C, lacking eosinophils and neutrophils. Extensive folliculotropism characteristic to type F was observed in 1 of 14 case. Significant MUM1 and PD1 expression were detected in 2 of 14 and 3 of 14 cases, respectively. We concluded that CD8+ LyP may present with different histopathological features compared with type D, similar to CD4+ LyP variants. Differential diagnoses include CD8+ papular MF, folliculotropic MF and anaplastic large cell lymphoma in addition to primary cutaneous aggressive epidermotropic T-cell lymphoma. We emphasise that rare CD8+ LyP cases may exist with CD30-negativity.

T-cell receptor (TCR)-transgenic models of acute graft-versus-host disease (aGvHD) offer a straightforward and highly controlled approach to study the mechanisms and consequences of T-cell activation following allogeneic hematopoietic stem cell transplantation (aHSCT). Here, we report that aHSCT involving OT-I mice as donors, carrying an ovalbumin-specific CD8+ TCR, and Act-mOVA mice as recipients, expressing membrane-bound ovalbumin driven by the β-actin promoter, induces lethal aGvHD in a CD8+ T-cell-dependent, highly reproducible manner, within 4-7 days. Tracking of UBC-GFP/OT-I graft CD8+ T cells disclosed heavy infiltration of the gastrointestinal tract, liver, and lungs at the onset of the disease, and histology confirmed hallmark features of gastrointestinal aGVHD, hepatic aGvHD, and aGvHD-associated lymphocytic bronchitis in infiltrated organs. However, T-cell infiltration was virtually absent in the skin, a key target organ of human aGvHD, and histology confirmed the absence of cutaneous aGVHD, as well. We show that the model allows studying CD8+ T-cell responses in situ, as selective recovery of graft CD45.1/OT-I CD8+ T cells from target organs is simple and feasible by automated tissue dissociation and subsequent cell sorting. Assessment of interferon-gamma production by flow cytometry, granzyme-B release by ELISA, TREC assay, and whole-genome gene expression profiling confirmed that isolated graft CD8+ T cells remained intact, underwent clonal expansion, and exerted effector functions in all affected tissues. Taken together, these data demonstrate that the OT-I/Act-mOVA model is suitable to study the CD8+ T-cell-mediated effector mechanisms in a disease closely resembling fatal human gastrointestinal and hepatic aGVHD that may develop after aHSCT using HLA-matched unrelated donors.

Context: Follicular lymphoma (FL) is the most common type of indolent non-Hodgkin lymphomas, with an average overall survival rate of 15 years. The majority of FL patients experience disease progression or high-grade transformation to a more aggressive lymphoma, raising the need for effective treatment response monitoring, which, however, is hampered by the limited specificity and sensitivity of the most widely used, imaging-based PET-CT method. Molecular analysis of tumor-derived circulating DNA (ctDNA), frequently referred as liquid biopsy, is a promising, minimally invasive, radiation-free disease monitoring tool for patients suffering from a wide range of different tumor types. Recent studies interrogating the genomic background of FL have revealed activating mutations in the epigenetic regulator EZH2 gene in 25% of patients at diagnosis. Objective: In this feasibility study, we tested the power of detection and time-resolved monitoring of EZH2 mutations in ctDNA of FL patients receiving immunochemotherapy (ICT). Methods: Thirty-five blood plasma samples have been collected from 19 EZH2 mutant FL patients treated with ICT. After ctDNA isolation, EZH2 mutations were screened in each sample using digital droplet PCR (Bio-Rad Laboratories, USA). The acquired genetic results were compared with PET-CT-based imaging data where available. Results: EZH2 mutations were detected in plasma samples of four patients suffering from active or transformed FL. All patients with EZH2 wild type plasma samples were in complete or partial remission. In patients with EZH2 mutation-positive ctDNA, allele frequencies of the mutations correlated with the amount of metabolically active tumor sites observed on PET-CT scan images. Variant allele frequencies of EZH2 mutations rapidly declined or dropped below the detection limit upon successful treatment, while in one patient, treatment failure was associated with high EZH2 variant allele frequency. We also demonstrated spatial heterogeneity of EZH2 mutations in another case where different EZH2 mutations deriving from distinct anatomical sites could simultaneously be detected in the plasma. Conclusions: Our results suggest that liquid biopsy-based EZH2 mutation analysis with sensitive digital droplet PCR method offers a real-time, radiation-free, sensitive treatment response monitoring tool for patients with active EZH2 mutant FL.

Multiple myeloma (MM) is a genetically heterogeneous disease with a diverse clinical outcome. Copy number alterations (CNAs), including whole chromosome and subchromosomal gains and losses, are common contributors of the pathogenesis and have demonstrated prognostic impact in MM. We tested the performance of digital multiplex ligation-dependent probe amplification (digitalMLPA), a novel technique combining MLPA and next-generation sequencing, to detect disease-related CNAs. Copy number status at 371 genomic loci was simultaneously analyzed in 56 diagnostic bone marrow samples, which were also examined by conventional MLPA and interphase fluorescence in situ hybridization (iFISH). On average, digitalMLPA identified 4.4 subchromosomal CNAs per patient. The increased number of probes compared with conventional MLPA allowed a detailed mapping of CNAs, especially on chromosome 1, where 24 different patterns were observed in 38 patients harboring loss(1p) and/or gain(1q). iFISH, MLPA, and digitalMLPA results at loci investigated by multiple methods showed a congruency of 95%. Besides precise characterization of hyperdiploid karyotypes not efficiently achievable by iFISH or MLPA, digitalMLPA unraveled 156 CNAs not detected by the other two methods in 45 patients (80%). In addition, we provide proof of principle that digitalMLPA can detect known point mutations, in this case the BRAFV600E. Our study demonstrates the robustness of digitalMLPA to profile CNAs and to screen point mutations in MM, which could efficiently be used in myeloma diagnostics.

Mutations of the multifunctional protein calreticulin (CALR) are recognised as one of the main driver alterations involved in the pathogenesis of Philadelphia negative myeloproliferative neoplasms (Ph- MPN) and also represent a major diagnostic criterion in the most recent World Health Organization classification of myeloid neoplasms. Nowadays, quantitative assessment of the driver mutations is gaining importance, as recent studies demonstrated the clinical relevance of the mutation load reflecting the size of the mutant clone. Here, we performed for the first time a manual and automated quantitative assessment of the CALR mutation load at protein level using CAL2, a recently developed CALR mutation specific monoclonal antibody, on a cohort of 117 patients with essential thrombocythemia (ET) or primary myelofibrosis (PMF) and compared the CALR protein mutation loads with the CALR mutation load values established by a molecular assay. Eighteen different CALR mutations were detected in the cohort of the 91 CALR mutant cases. Mutation loads of the CALR mutations were between 13% and 94% with mean value in PMF cases significantly higher than ET cases (49.94 vs 41.09; t-test, p=0.004). Cases without CALR mutation (n=26) showed no or only minimal labelling with the CAL2 antibody, while all 18 different types of CALR mutations were associated with CAL2 labelling. The CALR mutation load showed a significant correlation (p=0.03) with the occurrence of major thrombotic events, with higher mutation load in patients presenting with these complications. We report a 100% concordance between the mutation status determined by immunohistochemistry and the CALR molecular assay, and we extend the applicability of this approach to 16 rare CALR mutations previously not analysed at protein level.

Lymph node involvement of chronic lymphocytic leukaemia/small lymphocytic lymphoma (CLL/SLL) is characterised by the diffuse infiltration of small neoplastic lymphocytes, which is accompanied by the presence of proliferation centres (PCs) comprising prolymphocytes and paraimmunoblasts. There is increasing evidence of accumulation of various molecular alterations in the tumour cells of PCs, which may explain why extended PCs are related to a less favourable prognosis. To further characterize PCs, we compared the expression level of EZH2 protein, the overexpression of which has recently been recognized as poor prognostic factor in CLL/SLL, in the PCs and the intervening small cell areas in lymph nodes of 15 patients with CLL/SLL. We also investigated the mutational profile of EZH2 and the expression of its upstream regulators c-Myc, E2F1, pRB and miR-26a. Our results showed a significantly increased expression of EZH2 in the PCs. No EZH2 mutations were detected, however, overexpression of c-Myc, E2F1 and pRb proteins as well as reduced expression of the tumor suppressor miR-26a were demonstrated in the PCs. In summary our findings indicate that EZH2 pathway is significantly upregulated in the PCs of CLL/SLL lymph nodes, providing further evidence for the distinguished biological features of the PCs.

Chronic lymphocytic leukemia (CLL) is characterized by a neoplastic B-cell population coexpressing CD5 and CD23; however, the expression of CD23 is variable. In human, two isotypes of CD23 have been identified and related to different functions. The aim of our study was to investigate the relative expression of the two CD23 isotypes in CLL and find possible correlation with other prognostic factors. The expression of CD23 isotypes was analyzed in 54 cases of CLL by polymerase chain reaction (PCR) and quantitative real-time PCR. The immunophenotype of CLL cells was characterized by flow cytometry. We demonstrated a higher CD23a than CD23b expression of CLL cells. Our results also revealed two subsets of CLL cases with a distinct CD23 isotype expression pattern. Thirty-two percent of the cases (group CLL1) showed both low mRNA level of CD23 isotypes and high protein levels of CD20 and CD38 in contrast to group CLL2 with high CD23 mRNA levels. By correlating these results to the presence of prognostic factors determined by fluorescence in situ hybridization, we found that the majority of the cases of group CLL1 (14/17) carried trisomy 12. In summary, our results confirm a high CD23a/CD23b ratio of the CLL cells and demonstrate that in a subset of CLL cases, low CD23 expression together with high CD20 and CD38 expressions may serve as a surrogate for trisomy 12. Copyright © 2015 John Wiley & Sons, Ltd.

Proliferation centres (PCs) are histological hallmarks of lymph nodes in chronic lymphocytic leukaemia/small lymphocytic lymphoma (CLL/SLL). Chromosomal abnormalities have already been described to accumulate preferably in the PCs as opposed to the intervening small cell areas. To further characterize the pathogenic role of PCs, the expression levels of 17 selected miRs known to be involved in the development of CLL/SLL were compared in the PCs and the intervening small cell areas in lymph nodes of 15 patients with CLL/SLL. The miR expression levels were also compared to the cytogenetic alterations defined by FISH analysis. Our results show that two known oncomiRs, miR-155 and -92a were upregulated and the tumour suppressor miR-150 was downregulated in the PCs. Low expression of miR-150 was also associated with loss of 11q. In summary we found significantly higher expression of oncomiRs and lower expression of a tumour suppressor miR in PCs of CLL/SLL lymph nodes, which support the hypothesis that the PCs may drive the disease and play a role in progression.