👤 Erika Di Biase

Lipid abnormalities are emerging as key pathogenic mechanisms in neurodegenerative diseases, such as Alzheimer's disease, Parkinson's disease, and Lewy body dementia. Astrocytes in the brain provide apolipoprotein E (APOE) proteins and influence neuronal metabolism and health. Using live-cell imaging and objective neurite imaging techniques, we induced cellular lipid load (cholesterol and triglycerides) by inhibiting the lysosomal cholesterol transport protein NPC1 in human neuron-astrocyte cocultures and examined the effects of CRISPR-edited APOE3 and APOE4 human astrocytes on the rescue of dystrophic neurites, where axons and dendrites of nerve cells become disfigured. APOE3, but not APOE4 or APOE knockout, astrocytes prevented cholesterol- and lipid-induced neurite damage in APOE4 neurons. In the media of APOE3 neuron-astrocyte cocultures, high-density lipoprotein-like particles were larger and presumably more lipidated than those in equivalent APOE4 cocultures. This discovery highlights that living APOE3 astrocytes control key biological mechanisms by physiologically enhancing lipid cellular homeostasis and rescuing lipid-induced neurite structural abnormalities relevant to Alzheimer's disease and neurodegenerative diseases. Show less

Testicular adult granulosa cell tumors (AGCTs) are rare and show several clinical, pathological, and molecular differences with their ovarian counterparts. FOXL2 p.Cys134Trp, the ubiquitous molecular driver of ovarian AGCTs, is infrequent (~ 7%) in testicular AGCTs. Recently, FGFR1 hotspot mutations were reported as a potentially "alternative molecular driver" in FOXL2-wild type (WT) ovarian AGCTs. A systematic assessment of FGFR1 status has not been performed in testicular AGCTs. Recently, our group analyzed a series of twenty testicular AGCTs using two NGS panels that lacked coverage of FGFR1. Among twelve cases analyzed successfully, none harbored pathogenic FOXL2 variants. In this study, we reassessed the tumors from our prior series with an NGS panel that covers FGFR1. Among the 14 tumors (70%) that were sequenced successfully, none harbored pathogenic FGFR1 variants. Considering the AGCTs assessed in this study and those previously reported in the literature, none of the 24 tumors analyzed to date have shown pathogenic FGFR1 variants. The present study reinforces the concept that testicular sex cord-stromal tumors classified as AGCTs are different from ovarian counterparts. Show less

Apolipoprotein E (ApoE) variants are central to Alzheimer's disease (AD), Lewy body dementia (LBD) and Niemann-Pick disease type C (NPC). The ApoE4 variant elevates AD risk by 3-15-fold. ApoE's normal function in lipid transport is known. The question remains how different ApoE isoforms cause cellular pathogenesis. We determined the effects of ApoE isoforms on lipid accumulation induced by inhibiting the endo-lysosomal cholesterol transporter NPC1. In human fibroblasts and astrocytes, NPC1 inhibition caused a 4-fold cholesterol accumulation and mis-localization with altered cholesterol sensing and increased synthesis of cholesterol and triglycerides. Total APP, APP C-terminal fragments (CTF) and BACE1 levels increased 3-fold. Remarkably, the intracellular neutral lipids co-localized with APP and APP C-terminal fragments. ApoE2 and ApoE3, but not ApoE4, reduced intracellular cholesterol levels by 67% and 62%, respectively, normalized APP, BACE, CTF, and improved cell survival. ApoE4 combined with a synthetic lipopeptide, which increased the proportion of large lipidated ApoE4 particles, corrected these abnormalities. This highlights ApoE in lipid pathogenesis and targeting ApoE4 lipidation to restore ApoE4 function. Show less

Molecular analysis of Each participating institution was requested to apply its own diagnostic testing strategy on 8 sections obtained from artificial reference specimens built to harbor Overall, cell resuspension yielded higher amounts of DNA and RNA (SNU16 61.5 ng/µl, 38100.0 pg/µl; RT112 118.0/µl, 2140.0 pg/µl, respectively) in comparison with SNU16+ RT112 mixing cell block (0.7 ng/µl DNA and 412.0 pg/µl RNA). Moreover, FFPE samples showed a higher fragmentation index (DIN 1.2 and RIN not calculated) compared with cell line resuspension (DIN 2.2 and 9.5 for SNU16 and RT112; RIN 3.9 and 6.8 for SNU16 and RT112). All participating institutions identified NGS represents the most suitable approach in molecular profiling of Show less

The early detection of cutaneous melanoma, a potentially lethal cancer with rising incidence, is fundamental to increasing survival and therapeutic adjustment. In stages II-IV especially, additional indications for adjuvant therapy purposes after resection and for treatment of metastatic patients are urgently needed. We investigated whether the fatty acid (FA) and protein compositions of small extracellular vesicles (sEV) derived from the plasma of stage 0-I, II and III-IV melanoma patients ( Show less

The tumor microenvironment (TME) includes immune (T, B, NK, dendritic), stromal, mesenchymal, endothelial, adipocytic cells, extracellular matrix, and cytokines/chemokines/soluble factors regulating various intracellular signaling pathways (ISP) in tumor cells. TME influences the survival/progression of prostate cancer (PC), enabling tumor cell immune-evasion also through the activation of the PD-1/PD-L1 axis. We have performed a systematic literature review according to the PRISMA guidelines, to investigate how the PD-1/PD-L1 pathway is influenced by TME and ISPs. Tumor immune-escape mechanisms include suppression/exhaustion of tumor infiltrating cytotoxic T lymphocytes, inhibition of tumor suppressive NK cells, increase in immune-suppressive immune cells (regulatory T, M2 macrophagic, myeloid-derived suppressor, dendritic, stromal, and adipocytic cells). IFN-γ (the most investigated factor), TGF-β, TNF-α, IL-6, IL-17, IL-15, IL-27, complement factor C5a, and other soluble molecules secreted by TME components (and sometimes increased in patients' serum), as well as and hypoxia, influenced the regulation of PD-L1. Experimental studies using human and mouse PC cell lines (derived from either androgen-sensitive or androgen-resistant tumors) revealed that the intracellular ERK/MEK, Akt-mTOR, NF-kB, WNT and JAK/STAT pathways were involved in PD-L1 upregulation in PC. Blocking the PD-1/PD-L1 signaling by using immunotherapy drugs can prevent tumor immune-escape, increasing the anti-tumor activity of immune cells. Show less