Journal of Translational Medicine最新文献

Background: Tissue-nonspecific alkaline phosphatase (TNSALP) and intestinal alkaline phosphatase (IAP) are functionally similar enzymes, but their relationship in hypophosphatasia (HPP) remains unexplored. This study investigated the impact of HPP-a condition caused by ALPL gene mutations that impair TNSALP function-on serum and fecal IAP activity.

Methods: Total alkaline phosphatase (ALP) activity and isoenzyme-specific activities (using selective inhibitors: L-homoarginine for TNSALP, L-phenylalanine for IAP) were measured in serum and stool samples from 30 HPP patients and 30 matched healthy controls, alongside biochemical parameters correlations.

Results: In serum, IAP activity showed a non-significant decrease in HPP patients compared to controls, while TNSALP and total ALP activity were reduced in HPP patients. In stools, both total ALP and IAP activities were significantly decreased compared to the control group. Multivariate linear regression revealed a strong positive association between TNSALP and IAP in both serum and feces, independent of age and sex. In serum, TNSALP and IAP were key predictors of total ALP activity (B = 0.876 and B = 0.745, respectively; p < 0.001; R² = 0.9396), with TNSALP also predicting serum IAP levels (B = 0.164; p < 0.001). In feces, IAP was the strongest predictor of total ALP activity (B = 0.921; p < 0.001), and fecal TNSALP strongly predicted IAP levels (B = 0.883; p < 0.001). Serum TNSALP activity correlated with bone metabolism markers, inflammation, underscoring its potential systemic role.

Conclusions: IAP does not seem to compensate for reduced TNSALP activity in HPP. Instead, their tight association suggests a coordinated regulation between the two isoenzymes, with diminished fecal IAP potentially contributing to gut inflammation in HPP. These findings clarify the interplay between TNSALP and IAP and their clinical implications.

Background: Gene therapy (GT) using retroviral vectors (RVs) is efficacious in treating monogenic diseases. However, there is an inherent risk for severe adverse effects due to insertional mutagenesis. Preclinical safety assessment and patient monitoring are inevitable in GT. To assess the genotoxic risk of novel RV vectors, mainly murine hematopoietic stem and progenitor cells (HPSCs) are routinely used, because human HSPCs cannot be immortalized in vitro using mutagenic vectors. In this study, we aim to identify early signs of clonal outgrowth by performing integration site analyses (ISA).

Methods: The small molecules A83-01, pomalidomide, and UM171 (APU) were used for the ex vivo expansion, lentiviral transduction, and long-term cultivation of umbilical cord blood-derived HSPCs. We determined the influence of APU on the stemness of HSPCs and their differentiation capacity via single-cell RNA sequencing (scRNA seq) and in xenotransplantation studies. To track vector insertion site dynamics, we transduced 7-day expanded HSPCs with a mutagenic or a safer RV. ISA was conducted in human HSPCs over a 5-week cultivation in vitro and compared to the bone marrow of xenotransplanted mice to assess clonal skewings.

Results: APU supported the expansion of CD34⁺CD38^-CD45RA^-CD90⁺EPCR⁺ HSPCs. scRNA seq confirmed the enrichment of HSC signature genes in APU-expanded HSPCs compared to the clinically used medium SFT3 (SCF, FLT3-L, TPO, IL-3). After RV transduction, APU still maintained around 30% of CD34⁺ cells for 5 more weeks. Without the compounds, already 2 weeks post-transduction, less than 10% of cells were CD34⁺. The long-term culture allowed the detection of high-risk integrations of the mutagenic SIN-LV.SF in MEIS1 or SUSD6 due to their increasing abundance over time. Bone marrow of xenotransplanted mice was less clonal but did not support the outgrowth of insertional mutants. Overall, APU increased clonal diversity.

Conclusions: Our findings propose that long-term cultivation of transduced HSPC in APU allows for outgrowth of clonal integration sites. The decrease of clonality has been observed in gene therapy patient's years after treatment. Thus, the in vitro model could be used to develop novel human HSPC-based genotoxicity assays that predict insertional mutagenesis, in addition to existing preclinical biosafety assays.

Background: Neutrophils are the most abundant circulating leukocytes and are raipidly recruited to inflammatory sites as key effectors of innate immunity. Nasopharyngeal carcinoma (NPC), an Epstein-Barr virus (EBV)-associated epithelial malignancy endemic in Southeast Asia and North Africa, develops within a chronically inflamed and immunologically specialized tumor microenvironment (TME). Current standard therapies (concurrent chemoradiotherapy and induction chemotherapy) face challenges of recurrence and metastasis, highlighting the need to explore the role of neutrophils in NPC progression and potential therapeutic targets.

Main body: EBV shapes the cytokine/chemokine milieu in the NPC TME, driving neutrophil recruitment and reprogramming into a continuum of tumor-associated neutrophils (TANs) and PMN-MDSC-like states. These neutrophils promote tumor progression via immunosuppression, extracellular matrix remodeling, angiogenesis, and metastasis. Neutrophil extracellular traps (NETs) further mediate immune evasion, thrombosis, and dissemination. Clinically, peripheral inflammatory indices correlate with NPC prognosis but are limited by heterogeneous cutoffs and confounding factors. Neutrophils also exhibit context-dependent anti-tumor effects. Potential therapies include targeting the CXCL8-CXCR1/2 axis, modulating NET formation, and combining with immune checkpoint inhibitors.

Conclusions: This review establishes a unifying framework linking EBV-driven inflammation to neutrophil plasticity, NET biology, and NPC progression. Neutrophils are dynamic, targetable components with dual pro-tumor and anti-tumor roles. While neutrophil-related indices hold prognostic value, their clinical translation requires standardization and integration with other biomarkers. Targeting suppressive neutrophil programs and NETs offers promising strategies to improve therapeutic efficacy and overcome treatment resistance in NPC.