Bernadette Kalman

Mitochondrial energy metabolism and apoptosis regulation in glioblastoma

Glioblastoma is the most aggressive form of gliomas and is associated with short survival. Recent advancements in molecular genetics resulted in the identification of glioma genomic, epigenomic and transcriptomic hallmarks, and multidimensional data allowed clustering of glioblastomas into molecular subtypes. Parallel with these developments, much scientific attention has been attracted by the exploration of two functional processes linked to mitochondrial regulation. One of these processes involves genomic and mitochondrial gene mutations, mitochondrial protein expression modifications and altered metabolic regulation that define glioblastoma. The second mitochondrially-centered process involves complex molecular interactions and pathways that influence the extrinsic or the intrinsic mechanisms of apoptosis regulation and may underlie the uncontrolled spreading, recurrence and drug resistance of glioblastoma. While the available data are not yet comprehensive, these two complex processes represent important aspects of tumor cell biology, which may provide complementary opportunities for therapeutic manipulations of this highly resistant tumor type.

Hormonal and biochemical parameters correlated with bone densitometric markers in prepubertal Hungarian children.

BACKGROUND The conditions that define bone development in prepuberty profoundly influence bone health later in life. We aimed to reveal important determinants of bone mass in Tanner stage I. METHODS We studied 84 healthy children (43 girls and 41 boys) aged 7 to 11 years. Serum estradiol (E2), 25-hydroxyvitamin D3-vitamin [25(OH)D3], intact parathyroid hormone (PTHi), osteocalcin (OC) and β-crosslaps (CTXs) were longitudinally analyzed (Roche Diagnostics System). Total and spine bone mineral content (tBMC and LBMC) and density (tBMD and LBMD) were assessed, and total fat body mass index (FBMi) was calculated (DXA Lunar Prodigy). RESULTS The serum PTHi, OC and LBMD values were significantly higher in girls than in boys. The mean 25(OH)D3 level was lower but not significantly in girls compared to boys. Significant negative correlation was found between PTHi and 25(OH)D3 levels (r=-0.28; p=0.011) when tested in all subjects, but no correlation was detected when the gender groups were separately tested. There was a trend for higher E2 levels in girls. Significant positive correlation (r=0.32; p=0.042) was detected between FBMi and E2 concentration in girls only. A significant negative correlation was found between E2 and 25(OH)D3 levels (r=-0.37, p<0.05) in girls with elevated (>3.6pmol/l) PTHi and with suboptimal (<75nmol/l) 25(OH)D3 levels. Furthermore, positive correlations were noted between E2 and CTXs and OC (r=0.54, p<0.01 and r=0.39, p<0.03) and a marginally significant positive correlation (r=0.33; p=0.06) was detected between OC and PTHi levels in girls. However, we detected no correlations when these markers were analyzed in boys. There was a significant correlation between E2 and all BMC and LBMD values in both genders. The tBMD, LBMD and tBMC values showed weak, but significant negative associations with 25OHD3 levels (β=-0.44 to -0.55; p<0.001) in girls only. All BMD and BMC values were positively predicted by OC levels, but not by CTXs, in both genders. Among the biochemical markers, E2 was the only factor correlating with all dependent variables (BMCs and BMDs) in both genders. Among all parameters analyzed, FBMi (β=0.64) showed the strongest influence on tBMC characteristically in girls only. CONCLUSIONS Our results support that 1.) E2 levels play a key role in defining bone turnover and bone mass in both genders already in prepuberty; 2.) high PTHi levels in childhood should be evaluated with caution, because the normal range for serum PTHi in different Tanner stage groups is not well established; and 3.) the negative correlation between 25(OH)D and E2 and the positive correlation between PTHi and OC suggest that estrogens regulate PTHi indirectly and cause lower circulating 25(OH)D3 levels. We propose that the decreased levels of 25(OH)D3 reflect not the real vitamin supply, but may rather be the result of E2 regulation. Therefore, the actual serum 25OHD levels may underestimate the availability of factors supporting bone formation.

PARP1 expression and its correlation with survival is tumour molecular subtype dependent in glioblastoma

Overexpression of PARP1 exists in various cancers, including glioblastoma (GBM). Although PARP1 inhibition is a promising therapeutic target, no comprehensive study has addressed PARP1s expression characteristics and prognostic role regarding molecular heterogeneity in astrocytomas including GBM. Our aim was to evaluate PARP1s associations with survival, WHO grade, lineage specific markers, and GBM transcriptomic subtypes. We collected genomic and clinical data from the latest glioma datasets of The Cancer Genome Atlas and performed PARP1, ATRX, IDH1, and p53 immunohistochemistry on GBM tissue samples. We demonstrated that PARP1 gain and increased mRNA expression are characteristics of high-grade astrocytomas, particularly of Proneural and Classical GBM subtypes. Additionally, higher PARP1 levels exhibited an inverse correlation with patient survival (p<0.005) in the Classical subgroup. ATRX (p=0.006), and TP53 (p=0.015) mutations were associated with increased PARP1 expression and PARP1 protein level correlated with ATRX loss and p53 overexpression. Furthermore, higher PARP1 expression together with wildtype TP53 indicated shorter survival (p=0.039). Therefore, due to subtype specificity, PARP1 expression level and TP53 mutation status are reliable marker candidates to distinguish Proneural and Classical subtypes, with prognostic and therapeutic implications in GBM.

Three novel mutations and genetic epidemiology analysis of the Gap Junction Beta 1 (GJB1) gene among Hungarian Charcot-Marie-Tooth disease patients.

Pathogenic variants of the gap junction beta 1 (GJB1) gene are responsible for the Charcot-Marie-Tooth neuropathy X type 1 (CMTX1). In this study, we report the mutation frequency of GJB1 in 210 Hungarian CMT patients and the phenotype comparison between male and female CMTX1 patients. Altogether, 13 missense substitutions were found in the GJB1 gene. Among them, 10 have been previously described as pathogenic variants (p.Arg15Trp, p.Val63Ile, p.Leu89Val, p.Ala96Gly, p.Arg107Trp, p.Arg142Gln, p.Arg164Trp, p.Arg164Gln, p.Pro172Ala and p.Asn205Ser), while 3 were novel, likely pathogenic alterations (p.Val13Glu, p.Glu186Gly, p.Met194Ile). These variants were not present in controls and were predicted as disease causing by in silico analysis. The frequency of the variants was 6.7% in our cohort which refers to a common cause of hereditary neuropathy among Hungarian patients. In addition to the classical phenotype, CNS involvement was proved in 26.1% of the CMTX1 patients. GJB1 pathogenic alterations were found mainly in males but we also detected them in female probands. The statistical analysis of CMTX1 patients revealed a significant difference between the two genders regarding the age of onset, Charcot-Marie-Tooth neuropathy and examination scores.

Rare autoimmune disorders with Mendelian inheritance

Abstract Autoimmune diseases represent a heterogeneous group of common disorders defined by complex trait genetics and environmental effects. The genetic variants usually align in immune and metabolic pathways that affect cell survival or apoptosis and modulate leukocyte function. Nevertheless, the exact triggers of disease development remain poorly understood and the current therapeutic interventions only modify the disease course. Both the prevention and the cure of autoimmune disorders are beyond our present medical capabilities. In contrast, a growing number of single gene autoimmune disorders have also been identified and characterized in the last few decades. Mutations and other gene alterations exert significant effects in these conditions, and often affect genes involved in central or peripheral immunologic tolerance induction. Even though a single genetic abnormality may be the disease trigger, it usually upsets a number of interactions among immune cells, and the biological developments of these monogenic disorders are also complex. Nevertheless, identification of the triggering molecular abnormalities greatly contributes to our understanding of the pathogenesis of autoimmunity and facilitates the development of newer and more effective treatment strategies.

Molecular Subgroups of Glioblastoma– an Assessment by Immunohistochemical Markers

Comprehensive molecular characterization of and novel therapeutic approaches to glioblastoma have been explored as a result of advancements in biotechnologies. In this study, we aimed to bring basic research discoveries closer to clinical practice and ultimately incorporate molecular classification into the routine histopathological evaluation of grade IV gliomas. Integrated results of genome-wide sequencing, transcriptomic and epigenomic analyses by The Cancer Genome Atlas Network defined the classic, proneural, neural and mesenchymal subtypes of this tumor. In a retrospective cohort, we analyzed selected subgroup-defining molecular markers in formalin-fixed paraffin-embedded surgical specimens by immunohistochemistry. Quantitative and qualitative scores of marker expression were tested in hierarchical cluster analyses to evaluate segregations of the molecular subgroups, which then were correlated with clinical parameters including patients’ age, gender and overall survival. Our study has confirmed the separation of molecular glioblastoma subgroups with clear trends regarding clinical correlations. Future analyses in a larger, prospective cohort using similar methods are expected to facilitate the development of a molecular diagnostic panel that may complement routine histological work up and support prognostication as well as treatment decisions in glioblastoma.

Contribution of the Wnt Pathway to Defining Biology of Glioblastoma

Glioblastoma (GBM), a highly lethal brain tumor, has been comprehensively characterized at the molecular level with the identification of several potential treatment targets. Data concerning the Wnt pathway are relatively sparse, but apparently very important in defining several aspects of tumor biology. The Wnt ligands are involved in numerous basic biological processes including regulation of embryogenic development, cell fate determination, and organogenesis, but growing amount of data also support the roles of Wnt pathways in the formation of many tumors, including gliomas. Two main Wnt pathways are distinguished: the canonical (β-catenin) and non-canonical (planar cell polarity, Wnt/Ca2+) routes. Wnt signaling regulates glioma stem cells (GSCs), thereby defining invasive potential, recurrence, and treatment resistance of GBM. Some observations suggest that the Wnt pathways are differentially active in molecular subtypes of this tumor, thereby may also guide prognostication and novel therapeutic decisions. In this review, we highlight main elements and biological relevance of the Wnt pathways, primarily focusing on the pathogenesis and subtypes of GBM. Finally, we briefly summarize newer therapeutic strategies targeting networks of the Wnt signaling cascades and their molecular associates that appear to be marked contributors to GBM aggressiveness.

Nusinersen a spinalis izomatrophia kezelésében

Until recently, the diagnosis of spinal muscular atrophy (SMA) has been associated with severe life-long motor disability in adults and with early death in infants. The new experimental therapeutic approaches of the last few years have become more and more promising, while nusinersen was approved for the treatment of SMA in December 2016 in the USA, and in May 2017 in Hungary. Our paper presents mechanisms and clinical benefits of this new medication, and highlights some of the other therapeutic strategies still in experimental stages.

Changing times – changing diseases. Review of the neuropathological autopsy documentations at the Markusovszky University Teaching Hospital (1964–2014)

INTRODUCTION Nearly 6000 autoptic studies were carried out during the last 50 years at the Laboratory of Neuropathology, Markusovszky University Teaching Hospital, Hungary. AIM The aim of the authors was to present those previously frequent and often fatal conditions that can be prevented or treated today. METHOD Retrospective analyses of the neuropathological documentations. RESULTS Measles-related subacute sclerosing panencephalitis caused death in 13 cases, the last occurred in 1991. The mandatory vaccination against the causative virus has eliminated this severe neurological complication. Fourteen lives were lost due to herpes simplex encephalitis, including the last case seen in 1999. Feasibility of early diagnosis and the availability of acyclovir therapy resulted in better outcome without fatality. Tuberculous meningitis still occurred in most recent years, although only sporadically. Recognition of this condition is not straightforward due to its rarity, and considerations for this disease are often omitted from the routine differential diagnosis. The generally low mortality rates in tick borne encephalitis further dropped after the introduction of vaccination. Altogether only 8 such cases were documented. The last fatal cases of neurolues were seen in the 1990s. However, syphilis itself has not disappeared, and the number of cases with newly acquired infection continues to rise. The introduction of intrathecal methotrexate and radiotherapy made possible the prevention or effective treatment of meningeal leukosis. A careful coordination of these treatment modalities, however, is important as nervous system complications may develop in the form of disseminated necrotizing leukoencephalopathy that is also reflected in the records. CONCLUSIONS The 50-year neuropathology documentation reflects changes in the occurrence of diseases, and it calls attention to those disorders which can be prevented or treated today, but may represent diagnostic challenges.

Változó idők – változó betegségek. A Markusovszky Egyetemi Oktatókórház neuropatológiai autopsziás anyagának áttekintése (1964–2014)@@@Changing times – changing diseases. Review of the neuropathological autopsy documentations at the Markusovszky University Teaching Hospital (1964–2014)

INTRODUCTION Nearly 6000 autoptic studies were carried out during the last 50 years at the Laboratory of Neuropathology, Markusovszky University Teaching Hospital, Hungary. AIM The aim of the authors was to present those previously frequent and often fatal conditions that can be prevented or treated today. METHOD Retrospective analyses of the neuropathological documentations. RESULTS Measles-related subacute sclerosing panencephalitis caused death in 13 cases, the last occurred in 1991. The mandatory vaccination against the causative virus has eliminated this severe neurological complication. Fourteen lives were lost due to herpes simplex encephalitis, including the last case seen in 1999. Feasibility of early diagnosis and the availability of acyclovir therapy resulted in better outcome without fatality. Tuberculous meningitis still occurred in most recent years, although only sporadically. Recognition of this condition is not straightforward due to its rarity, and considerations for this disease are often omitted from the routine differential diagnosis. The generally low mortality rates in tick borne encephalitis further dropped after the introduction of vaccination. Altogether only 8 such cases were documented. The last fatal cases of neurolues were seen in the 1990s. However, syphilis itself has not disappeared, and the number of cases with newly acquired infection continues to rise. The introduction of intrathecal methotrexate and radiotherapy made possible the prevention or effective treatment of meningeal leukosis. A careful coordination of these treatment modalities, however, is important as nervous system complications may develop in the form of disseminated necrotizing leukoencephalopathy that is also reflected in the records. CONCLUSIONS The 50-year neuropathology documentation reflects changes in the occurrence of diseases, and it calls attention to those disorders which can be prevented or treated today, but may represent diagnostic challenges.