Filamin A is involved in human intrahepatic cholangiocarcinoma aggressiveness and progression.

BACKGROUND & AIMS: Intrahepatic cholangiocarcinoma (iCCA) is a primary liver tumour, characterized by poor prognosis and lack of effective therapy. The cytoskeleton protein Filamin A (FLNA) is involved in cancer progression and metastasis, including primary liver cancer. FLNA is cleaved by calpain, producing a 90 kDa fragment (FLNACT ) that can translocate to the nucleus and inhibit gene transcription. We herein aim to define the role of FLNA and its cleavage in iCCA carcinogenesis. METHODS & RESULTS: We evaluated the expression and localization of FLNA and FLNACT in liver samples from iCCA patients (n = 82) revealing that FLNA expression was independently correlated with disease-free survival. Primary tumour cells isolated from resected iCCA patients expressed both FLNA and FLNACT , and bulk RNA sequencing revealed a significant enrichment of cell proliferation and cell motility pathways in iCCAs with high FLNA expression. Further, we defined the impact of FLNA and FLNACT on the proliferation and migration of primary iCCA cells (n = 3) and HuCCT1 cell line using silencing and Calpeptin, a calpain inhibitor. We observed that FLNA silencing decreased cell proliferation and migration and Calpeptin was able to reduce FLNACT expression in both the HuCCT1 and iCCA cells (p < .05 vs. control). Moreover, Calpeptin 100 µM decreased HuCCT1 and primary iCCA cell proliferation (p <.00001 vs. control) and migration (p < .05 vs. control). CONCLUSIONS: These findings demonstrate that FLNA is involved in human iCCA progression and calpeptin strongly decreased FLNACT expression, reducing cell proliferation and migration.

Tumor-Infiltrating B Lymphocytes: Promising Immunotherapeutic Targets for Primary Liver Cancer Treatment.

Hepatocellular carcinoma and cholangiocarcinoma are the fourth most lethal primary cancers worldwide. Therefore, there is an urgent need for therapeutic strategies, including immune cell targeting therapies. The heterogeneity of liver cancer is partially explained by the characteristics of the tumor microenvironment (TME), where adaptive and innate immune system cells are the main components. Pioneering studies of primary liver cancers revealed that tumor-infiltrating immune cells and their dynamic interaction with cancer cells significantly impacted carcinogenesis, playing an important role in cancer immune evasion and responses to immunotherapy treatment. In particular, B cells may play a prominent role and have a controversial function in the TME. In this work, we highlight the effect of B lymphocytes as tumor infiltrates in relation to primary liver cancers and their potential prognostic value. We also present the key pathways underlying B-cell interactions within the TME, as well as the way that a comprehensive characterization of B-cell biology can be exploited to develop novel immune-based therapeutic approaches.

Natural history of type 1 diabetes on an immunodysregulatory background with genetic alteration in B-cell activating factor receptor: A case report.

The immunological events leading to type 1 diabetes (T1D) are complex and heterogeneous, underscoring the necessity to study rare cases to improve our understanding. Here, we report the case of a 16-year-old patient who showed glycosuria during a regular checkup. Upon further evaluation, stage 2 T1D, autoimmune thrombocytopenic purpura (AITP), and common variable immunodeficiency (CVID) were diagnosed. The patient underwent low carb diet, losing > 8 kg, and was placed on Ig replacement therapy. Anti-CD20 monoclonal antibody (Rituximab, RTX) was administered 2 years after diagnosis to treat peripheral polyneuropathy, whereas an atypical mycobacteriosis manifested 4 years after diagnosis and was managed with prolonged antibiotic treatment. In the fifth year of monitoring, the patient progressed to insulin dependency despite ZnT8A autoantibody resolution and IA-2A and GADA autoantibody decline. The patient had low T1D genetic risk score (GRS = 0.22817) and absence of human leukocyte antigen (HLA) DR3/DR4-DQ8. Genetic analysis identified the monoallelic mutation H159Y in TNFRSF13C, a gene encoding B-cell activating factor receptor (BAFFR). Significant reduced blood B-cell numbers and BAFFR levels were observed in line with a dysregulation in BAFF-BAFFR signaling. The elevated frequency of PD-1+ dysfunctional Tfh cells composed predominantly by Th1 phenotype was observed at disease onset and during follow-up. This case report describes a patient progressing to T1D on a BAFFR-mediated immunodysregulatory background, suggesting a role of BAFF-BAFFR signaling in islet-specific tolerance and T1D progression.

Lentiviral correction of enzymatic activity restrains macrophage inflammation in adenosine deaminase 2 deficiency.

Adenosine deaminase 2 deficiency (DADA2) is a rare inherited disorder that is caused by autosomal recessive mutations in the ADA2 gene. Clinical manifestations include early-onset lacunar strokes, vasculitis/vasculopathy, systemic inflammation, immunodeficiency, and hematologic defects. Anti-tumor necrosis factor therapy reduces strokes and systemic inflammation. Allogeneic hematopoietic stem/progenitor cell (HSPC) transplantation can ameliorate most disease manifestations, but patients are at risk for complications. Autologous HSPC gene therapy may be an alternative curative option for patients with DADA2. We designed a lentiviral vector encoding ADA2 (LV-ADA2) to genetically correct HSPCs. Lentiviral transduction allowed efficient delivery of the functional ADA2 enzyme into HSPCs from healthy donors. Supranormal ADA2 expression in human and mouse HSPCs did not affect their multipotency and engraftment potential in vivo. The LV-ADA2 induced stable ADA2 expression and corrected the enzymatic defect in HSPCs derived from DADA2 patients. Patients' HSPCs re-expressing ADA2 retained their potential to differentiate into erythroid and myeloid cells. Delivery of ADA2 enzymatic activity in patients' macrophages led to a complete rescue of the exaggerated inflammatory cytokine production. Our data indicate that HSPCs ectopically expressing ADA2 retain their multipotent differentiation ability, leading to functional correction of macrophage defects. Altogether, these findings support the implementation of HSPC gene therapy for DADA2.