JMJD6 Shapes a Pro-tumor Microenvironment via ANXA1-Dependent Macrophage Polarization in Breast Cancer.

Breast cancer is the most common type of cancer in women worldwide, with the luminal subtype being the most widespread. Although characterized by better prognosis compared with other subtypes, luminal breast cancer is still considered a threatening disease due to therapy resistance, which occurs via both cell- and non-cell-autonomous mechanisms. Jumonji domain-containing 6, arginine demethylase and lysine hydroxylase (JMJD6) is endowed with a negative prognostic value in luminal breast cancer and, via its epigenetic activity, it is known to regulate many intrinsic cancer cell pathways. So far, the effect of JMJD6 in molding the surrounding microenvironment has not been explored.Here, we describe a novel function of JMJD6 showing that its genetic inhibition in breast cancer cells suppresses lipid droplet formation and ANXA1 expression, via estrogen receptor alpha and PPARα modulation. Reduction of intracellular ANXA1 results in decreased release in the tumor microenvironment (TME), ultimately preventing M2-type macrophage polarization and tumor aggressiveness. IMPLICATIONS: Our findings identify JMJD6 as a determinant of breast cancer aggressiveness and provide the rationale for the development of inhibitory molecules to reduce disease progression also through the remodeling of TME composition.

High tumor mutational burden and T-cell activation are associated with long-term response to anti-PD1 therapy in Lynch syndrome recurrent glioblastoma patient.

BACKGROUND: Glioblastomas (GBMs) in patients harboring somatic or germinal mutations of mismatch-repair (MMR) genes exhibit a hypermutable phenotype. Here, we describe a GBM patient with increased tumor mutational burden and germline MMR mutations, treated using anti-PD1 therapy. METHODS: A woman with newly diagnosed GBM (nGBM) was treated by surgery, radiotherapy, and temozolomide. The tumor recurred after 13 months leading to a second surgery and treatment with nivolumab. Whole-exome sequencing was performed on the nGBM, recurrent GBM (rGBM), and blood. Immune infiltration was investigated by immunohistochemistry and the immune response in the blood during treatment was analyzed by flow cytometry. RESULTS: High density of infiltrating CD163 + cells was found in both GBM specimens. Large numbers of CD3 + and CD8 + T cells were homogeneously distributed in the nGBM. The infiltration of CD4 + T cells and a different CD8 + T cell density were observed in the rGBM. Both GBM shared 12,431 somatic mutations, with 113 substitutions specific to the nGBM and 1,683 specific to the rGBM. Germline variants included pathogenic mutation in the MSH2 (R359S) gene, suggesting the diagnosis of Lynch syndrome. Systemic immunophenotyping revealed the generation of CD8 + T memory cells and persistent activation of CD4 + T cells. The patient is still receiving nivolumab 68 months after the second surgery. CONCLUSIONS: Our observations indicate that the hypermutator phenotype associated with germinal mutations of MMR genes and abundant T-cell infiltration contributes to a durable clinical benefit sustained by a persistent and robust immune response during anti-PD1 therapy.

Simultaneous Detection of NF1, SPRED1, LZTR1, and NF2 Gene Mutations by Targeted NGS in an Italian Cohort of Suspected NF1 Patients.

Neurofibromatosis type 1 (NF1) displays overlapping phenotypes with other neurocutaneous diseases such as Legius Syndrome. Here, we present results obtained using a next generation sequencing (NGS) panel including NF1, NF2, SPRED1, SMARCB1, and LZTR1 genes on Ion Torrent. Together with NGS, the Multiplex Ligation-Dependent Probe Amplification Analysis (MLPA) method was performed to rule out large deletions/duplications in NF1 gene; we validated the MLPA/NGS approach using Sanger sequencing on DNA or RNA of both positive and negative samples. In our cohort, a pathogenic variant was found in 175 patients; the pathogenic variant was observed in NF1 gene in 168 cases. A SPRED1 pathogenic variant was also found in one child and in a one year old boy, both NF2 and LZTR1 pathogenic variants were observed; in addition, we identified five LZTR1 pathogenic variants in three children and two adults. Six NF1 pathogenic variants, that the NGS analysis failed to identify, were detected on RNA by Sanger. NGS allows the identification of novel mutations in five genes in the same sequencing run, permitting unambiguous recognition of disorders with overlapping phenotypes with NF1 and facilitating genetic counseling and a personalized follow-up.

Adult leukoencephalopathies with prominent infratentorial involvement can be caused by Erdheim-Chester disease.

BACKGROUND: Leukoencephalopathies with prominent involvement of cerebellum and brainstem, henceforward called prominent infratentorial leukoencephalopathies (PILs), encompass a variety of inherited and acquired white matter diseases. Erdheim-Chester disease (ECD) is a rare non-Langerhans cell histiocytosis likely under-diagnosed as cause of adult PIL. METHODS: We reviewed the clinical and laboratory information of ten consecutive sporadic adult patients with PIL of unknown origin, who were investigated for ECD. RESULTS: There were seven males and three females; mean age at clinical onset was 49.6 years (range 38-59); cerebellar ataxia with or without other neurological symptoms was the only or the main clinical manifestation; diabetes insipidus was present in three individuals. Eight patients had white matter focal supratentorial abnormalities, in addition to the infratentorial white matter changes. Six out of eight patients had spinal cord lesions. Thoraco-abdominal CT showed periaortic sheathing in two patients, whole-body FDG-PET revealed increased glucose uptake in the long bones of the legs in five patients, brain FDG-PET showed overt infratentorial hypermetabolism in one patient. In eight patients, ECD was confirmed by bone scintigraphy, pathological data, or both. Two ECD patients treated with vemurafenib showed a marked improvement of neurological symptoms and brain MRI abnormalities at 1 year follow-up. CONCLUSIONS: Symptoms of PIL can be the only clinical manifestation of ECD. Adult patients with PIL of unknown origin should undergo investigations aimed at unveiling ECD, including bone scintigraphy and whole-body FDG-PET. The early diagnosis allows starting disease-modifying therapies of an otherwise life-threatening disease.

Identification and characterization of a new source of adult human neural progenitors.

Adult neural progenitor cells (aNPCs) are a potential source for cell based therapy for neurodegenerative diseases and traumatic brain injuries. These cells have been traditionally isolated from hippocampus, subventricular zone and white matter. However, there is still a need for an easily accessible source with better yield to counter the limitations of small surgical samples of previously characterized aNPCs. Here we show that ultrasonic aspirate (UA) samples currently considered as 'biological waste after surgery,' offer a good source for aNPCs. Furthermore, we show that culture conditions dictated the phenotype of cells across patients. The neurosphere-enriched cells were more similar to freshly isolated brain cells, while cells expanded adherently in serum conditions were similar to mesenchymal stem cells. However, cells expanded in these adherent conditions expressed some NPC and glial markers in addition to active canonical Wnt signaling. This suggests a mesenchymal-neuroectodermal hybrid nature of these cells. Finally, we show that UA-NPCs are comparable to those from neurogenic regions. Our findings suggest that UA samples can be used as a source for fresh and in vitro propagated aNPCs that could have various clinical applications.

Hypermutations in gliomas: a potential immunotherapy target.

Checkpoint inhibitors, like ipilimumab, nivolumab, and pembrolizumab, have provided a breakthrough in cancer immunotherapy, such as in the treatment of melanoma and colorectal and lung cancer. The close relationship between the number of mutations (mutational load) and the response to checkpoint immunotherapy has been convincingly demonstrated in these cancers. Hypermutations in tumors are caused by environmental factors, like UV radiations or cigarette smoking, or by germinal mutations affecting genes of the Mismatch Repair (MMR) machinery, as in the Lynch syndrome. In the context of a high mutational load, a number of neoantigens become visible to the immune system, creating the basis for effective T cell responses. In low- and high-grade gliomas, the most frequent brain tumors, germinal MMR defects are rare; however, hypermutations associated with mutations or decreased expression of MMR genes are rather frequent, occurring in 20-60% of the tumors at recurrence after alkylating chemotherapy with temozolomide. Ongoing clinical trials and genomic investigations will clarify if temozolomide-induced hypermutations, which usually occur in the presence of methylation of the methylguanine methyltransferase gene (MGMT), will be effectively targeted by immunotherapy with checkpoint inhibitors or dendritic cell immunotherapy, thus improving the survival expectations for patients affected by these tumors.

Ultrasonic Surgical Aspirate is a Reliable Source For Culturing Glioblastoma Stem Cells.

Glioma stem cells (GSCs) are thought to be the source of tumor growth and therapy resistance. To understand the biology of GSCs, and target these tumors therapeutically, we need robust strategies for in vitro expansion of primary GSCs. To date, tumor core biopsies have been the main established source of GSCs. Since these samples are used for diagnostic purposes, the available tissue for cell culture and therapeutic targeting can be limited. In addition, a core biopsy is usually taken from one part of the tumor, thus would be unlikely to represent intra-tumor heterogeneity. To overcome these problems, tissue fragments from all over the tumor can be collected using an ultrasonic aspirator during surgery, thus assembling a "global tumor biopsy". Usually, this ultrasonic aspirate (UA) sample is considered as biological waste after operations. Here, we show that UA samples offer a large and reliable source of live cells. Similar to core biopsies, UA samples enriched for GSCs that differentiated into neural lineages, showed inter-individual variation of GSC markers, and induced tumors. Molecular profiling showed that UA samples cover tumor heterogeneity better than core biopsies. These results suggest that UA samples can be used to establish large scale cultures for therapeutic applications.

LYRM7 mutations cause a multifocal cavitating leukoencephalopathy with distinct MRI appearance.

This study focused on the molecular characterization of patients with leukoencephalopathy associated with a specific biochemical defect of mitochondrial respiratory chain complex III, and explores the impact of a distinct magnetic resonance imaging pattern of leukoencephalopathy to detect biallelic mutations in LYRM7 in patients with biochemically unclassified leukoencephalopathy. 'Targeted resequencing' of a custom panel including genes coding for mitochondrial proteins was performed in patients with complex III deficiency without a molecular genetic diagnosis. Based on brain magnetic resonance imaging findings in these patients, we selected additional patients from a database of unclassified leukoencephalopathies who were scanned for mutations in LYRM7 by Sanger sequencing. Targeted sequencing revealed homozygous mutations in LYRM7, encoding mitochondrial LYR motif-containing protein 7, in four patients from three unrelated families who had a leukoencephalopathy and complex III deficiency. Two subjects harboured previously unreported variants predicted to be damaging, while two siblings carried an already reported pathogenic homozygous missense change. Sanger sequencing performed in the second cohort of patients revealed LYRM7 mutations in three additional patients, who were selected on the basis of the magnetic resonance imaging pattern. All patients had a consistent magnetic resonance imaging pattern of progressive signal abnormalities with multifocal small cavitations in the periventricular and deep cerebral white matter. Early motor development was delayed in half of the patients. All patients but one presented with subacute neurological deterioration in infancy or childhood, preceded by a febrile infection, and most patients had repeated episodes of subacute encephalopathy with motor regression, irritability and stupor or coma resulting in major handicap or death. LYRM7 protein was strongly reduced in available samples from patients; decreased complex III holocomplex was observed in fibroblasts from a patient carrying a splice site variant; functional studies in yeast confirmed the pathogenicity of two novel mutations. Mutations in LYRM7 were previously found in a single patient with a severe form of infantile onset encephalopathy. We provide new molecular, clinical, and neuroimaging data allowing us to characterize more accurately the molecular spectrum of LYRM7 mutations highlighting that a distinct and recognizable magnetic resonance imaging pattern is related to mutations in this gene. Inter- and intrafamilial variability exists and we observed one patient who was asymptomatic by the age of 6 years.