技术资料

Atezolizumab plus bevacizumab and lenvatinib are standard treatments for unresectable hepatocellular carcinoma; however,tumor markers such as alpha-fetoprotein and des-gamma-carboxy prothrombin have a limited ability to reflect treatment responses. Circulating tumor cells are non-invasive biomarkers associated with cancer stemness and treatment resistance. We assessed circulating tumor cell subsets expressing cancer stem cell markers (CD90,epithelial cell adhesion molecule,CD133,vimentin) using multiparametric flow cytometry at early and maximal response phases in patients receiving atezolizumab plus bevacizumab or lenvatinib. Early decreases in CD90-positive circulating tumor cells after therapy initiation were associated with tumor shrinkage and longer progression-free survival in both groups,as well as prolonged overall survival in the atezolizumab plus bevacizumab group. At maximal response,changes in CD90-positive circulating tumor cells reflected tumor burden more accurately than alpha-fetoprotein or des-gamma-carboxy prothrombin. These findings highlight the potential of CD90-positive circulating tumor cells to become dynamic biomarkers in systemic therapy for unresectable hepatocellular carcinoma. View Publication

Cancer research has long focused on mutations in normal body cells,but this approach has not produced major breakthroughs for most cancers. Our study explores a different concept that some aggressive cancers may actually arise from early reproductive cells called primordial germ cells,which normally develop into eggs and sperm. We created a new experimental model showing how a virus can transform human primordial germ cell-like cells into virus-positive Merkel cell carcinoma,a rare but deadly skin cancer. This model shows that cancers can emerge through changes in developmental states rather than relying solely on genetic mutations. By linking cancer development to early germ cells,our findings suggest a unifying explanation for both germ cell cancers and body cancers. This new perspective may guide more effective approaches to study,diagnose,and treat cancer by focusing on early human development rather than only DNA mutations and later developmental stages. View Publication

With the approval of the antibody-drug conjugate enfortumab vedotin (EV),NECTIN4 has emerged as a bona fide therapeutic target in urothelial carcinoma (UC). Here,we report the development of a NECTIN4-directed chimeric antigen receptor (CAR) T cell,which exhibits reactivity across cells expressing a range of endogenous NECTIN4,with enhanced activity in high expressors. We demonstrate that the PPARγ pathway,critical for luminal differentiation,transcriptionally controls NECTIN4,and that the PPARγ agonist rosiglitazone primes and augments NECTIN4 expression,thereby increasing sensitivity to NECTIN4-CAR T cell-mediated killing. NECTIN4-CAR T cells have potent anti-tumor activity even against EV resistant cells,which largely retain NECTIN4 expression,including in a post-EV biopsy cohort. Our results elucidate a therapeutically actionable mechanism that UC cells use to control NECTIN4 expression and suggest therapeutic approaches that leverage PPARγ agonists for rational combinations with NECTIN4-targeting agents in UC,as well as future potential treatment options for EV-refractory patients. Subject terms: Bladder cancer,Cancer immunotherapy,Cancer therapeutic resistance,Oncology,Bladder cancer View Publication

Despite the success of antiretroviral therapy in suppressing plasma viremia in people living with human immunodeficiency virus type-1 (HIV-1),persistent viral RNA expression in tissue reservoirs is observed and can contribute to HIV-1-induced immunopathology and comorbidities. Infection of long-lived innate immune cells,such as tissue-resident macrophages and microglia may contribute to persistent viral RNA production and chronic inflammation. We recently reported that de novo cytoplasmic expression of HIV-1 intron-containing RNA (icRNA) in macrophages and microglia leads to MDA5 and MAVS-dependent innate immune sensing and induction of type I IFN responses,demonstrating that HIV icRNA is a pathogen-associated molecular pattern (PAMP). In this report,we show that cytoplasmic expression of HIV-1 icRNA also induces NLRP1 inflammasome activation and IL-1β secretion in macrophages and microglia in an RLR- and endosomal TLR-independent manner. Infection of both macrophages and microglia with either replication-competent or single-cycle HIV-1 induced IL-1β secretion,which was attenuated when cytoplasmic expression of viral icRNA was prevented. While IL-1β secretion was blocked by treatment with caspase-1 inhibitors or knockdown of NLRP1 or caspase-1 expression in HIV-infected macrophages,overexpression of NLRP1 significantly enhanced IL-1β secretion in an HIV-icRNA-dependent manner. Immunoprecipitation analysis revealed interaction of HIV-1 icRNA,but not multiply-spliced HIV-1 RNA,with NLRP1,suggesting that HIV-1 icRNA sensing by NLRP1 is sufficient to trigger inflammasome activation. Together,these findings reveal a pathway of NLRP1 inflammasome activation induced by de novo expressed HIV icRNA in HIV-infected myeloid cells. View Publication

Metformin rejuvenates adult rat oligodendrocyte progenitor cells (OPCs) allowing more efficient differentiation into oligodendrocytes and improved remyelination,and therefore is of interest as a therapeutic in demyelinating diseases such as multiple sclerosis (MS). Here,we test whether metformin has a similar effect in human stem cell derived-OPCs. We assess how well human monoculture,organoid and chimera model culture systems simulate in vivo adult human oligodendrocytes,finding most close resemblance in the chimera model. Metformin increases myelin proteins and/or sheaths in all models even when human cells remain fetal-like. In the chimera model,metformin leads to increased mitochondrial area both in the human transplanted cells and in the mouse axons with associated increase of mitochondrial function/metabolism transcripts. Human oligodendrocytes from MS brain donors treated pre-mortem with metformin also express similar transcripts. Metformin’s brain effect is thus not cell-specific,alters metabolism in part through mitochondrial changes and leads to more myelin production. This bodes well for clinical trials testing metformin for neuroprotection. Subject terms: Oligodendrocyte,Multiple sclerosis,Multiple sclerosis,Regeneration and repair in the nervous system View Publication

Epigenetic modulators of the histone deacetylase (HDAC) family control key biological processes and are frequently dysregulated in cancer. There is superior activity of HDAC inhibitors (HDACi) in patients with myeloproliferative neoplasms (MPNs) that carry the Janus kinase-2 point mutant JAK2 V617F . This constitutively active tyrosine kinase activates signal-transducer-and-activator-of-transcription (STAT) transcription factors to promote cell proliferation and inflammatory processes. We reveal that the inhibition of HDAC1/HDAC2 with the clinically advanced HDACi romidepsin,the experimental HDACi entinostat and MERCK60,and genetic depletion of HDAC1/HDAC2 induce apoptosis and long-term growth arrest of primary and permanent MPN cells in vitro and in vivo. This treatment spares normal hematopoietic stem cells and does not compromise blood cell differentiation. At the molecular level,HDAC1 and HDAC2 control the protein stability of SIAH2 through acetylation. Genetic knockout experiments show that SIAH2 accelerates the proteasomal degradation of JAK2 V617F in conjunction with the E2 ubiquitin-conjugating enzyme UBCH8. SIAH2 binds to the surface-exposed SIAH degron motif VLP1002 in the catalytic domain of JAK2 V617F . At the functional level,SIAH2 knockout MPN cells are significantly less sensitive to HDACi. Global RNA sequencing verifies that JAK-STAT signaling is a prime target of SIAH2. Moreover,HDAC1 is an adverse prognostic factor in patients with acute myeloid leukemia ( n = 150,p = 0.02),being a possible complication of MPNs. These insights reveal a previously unappreciated link between HDAC1/HDAC2 as key molecular targets,the still undefined regulation of cytoplasmic-to-nuclear signaling by HDACs,and how HDACi kill JAK2 V617F -positive cells from MPN patients and mice with JAK2 V617F in vitro and in vivo. Subject terms: Haematological cancer,Oncogenes,Target identification,Haematopoietic stem cells View Publication

Prime editing is a promising approach for correcting pathogenic variants,but its efficiency remains variable across genomic contexts. Here,we systematically evaluated 12 modifications of the PEmax system for correcting the CFTR F508del pathogenic variant that caused cystic fibrosis in patient-derived airway basal cells. We chose EXO1 and FEN1 nucleases to improve the original system. While all tested variants showed comparatively low efficiency in this AT-rich genomic region,4-FEN modification demonstrated significantly improved editing rates (up to 2.13 fold) compared to standard PEmax. Our results highlight two key findings: first,the persistent challenge of AT-rich target sequence correction even with optimized editors,and second,the performance of 4-FEN suggests its potential value for other genomic targets. View Publication

Fatty-acid-hydroxylase-associated neurodegeneration (FAHN) is a rare neurodegenerative disorder caused by loss-of-function mutations in the FA2H gene,leading to impaired enzymatic activity and resulting in myelin sheath instability,demyelination,and axonal degeneration. In this study,we established a human in vitro model using neurons and oligodendrocytes derived from induced pluripotent stem cells (hiPSCs) of a FAHN patient. This coculture system enabled the investigation of myelination processes and myelin integrity in a disease-relevant context. Analyses using immunofluorescence and Western blot revealed impaired expression and localisation of key myelin proteins in oligodendrocytes and cocultures. FA2H-deficient cells showed reduced myelination,shortened internodes,and disrupted formation of the nodes of Ranvier. Additionally,we identified autophagy defects—a hallmark of many neurodegenerative diseases—including reduced p62 expression,elevated LC3B levels,and impaired fusion of autophagosomes with lysosomes. This study presents a robust hiPSC-based model to study FAHN,offering new insights into the molecular pathology of the disease. Our findings suggest that FA2H mutations compromise both the structural integrity of myelin and the efficiency of the autophagic machinery,highlighting potential targets for future therapeutic interventions. View Publication

Myeloproliferative Neoplasms (MPN) are malignancies of hematopoietic stem and progenitor cells (HSPCs) that lead to the overproduction of mature blood cells. These disorders include Essential Thrombocythemia (ET),Polycythemia Vera (PV),and Primary Myelofibrosis (PMF),primarily driven by somatic mutations such as JAK2 V617F . Research indicates that mesenchymal stromal cells (MSCs) support fibrosis in PMF,though their role in ET and PV remains less clear. Furthermore,in vivo studies of ET/PV HSPCs remain a challenge due to low engraftment levels in xenograft models. We employed a 3D scaffold model to create an MPN humanized xenograft mouse model,enabling in vivo functional studies of primary MPN progenitor cells and the supportive role of human MSCs. Using this model,we first demonstrated robust hematopoietic support of healthy (HD) HSPCs by PV and ET MSCs. We then investigated the role of MSCs in sustaining JAK2 V617F mutant cells by using a CRISPR‐Cas9 editing model,along with primary PV and ET HSPCs. Our results showed consistent engraftment of CRISPR‐edited JAK2 V617F mutant HSPCs and PV and ET patient‐derived HSPCs in scaffolds seeded with HD,PV,and ET stroma,providing the first in vivo evidence that PV and ET MSCs can sustain both healthy and MPN‐associated hematopoiesis. Furthermore,HD MSCs were also capable of sustaining PV and ET HSPCs in vivo. Overall,we present the first humanized MPN xenograft model that offers valuable insights into how human BM MSCs interact with JAK2 V617F mutant clones. View Publication

Spinal cord injury (SCI) remains a significant clinical challenge and poses a dramatic threat to the life quality of patients due to limited neural regeneration and detrimental post-injury alternations in tissue microenvironment. We developed a therapeutic approach by transplanting spinal neural progenitor cells (spNPGs),derived from human induced pluripotent stem cell (iPSC)-generated neuromesodermal progenitors,into a contusive SCI model in NOD-SCID mice. Single-cell RNA sequencing mapped the in vitro differentiation of iPSC-spNPGs,confirming their specification into spinal neuronal lineages. Single-nucleus transcriptomics at 1 week post-transplantation showed that the grafted cells differentiated in vivo into motor neurons and two interneuron subtypes (V2 and dI4). Additionally,spNPGs integrated into host neural circuits,enhancing synaptic connectivity,while simultaneously modulating the injury microenvironment by shifting microglia and astrocyte polarization toward anti-inflammatory and neuroprotective phenotypes. This dual mechanism promoted axonal regrowth,remyelination,and significant sensorimotor recovery,as evidenced by improved locomotor scores. Our findings highlight the therapeutic potential of human iPSC-spNPGs in reconstructing neural networks and mitigating secondary damage,providing compelling preclinical evidence for advancing stem cell-based SCI therapies. Subject terms: Stem-cell differentiation,Spinal cord injury View Publication

We have developed the HybriSeq method for single-cell RNA profiling,which utilizes in situ hybridization of multiple probes for targeted transcripts,followed by split-pool barcoding and sequencing analysis of the probes. We have shown that HybriSeq can achieve high sensitivity for RNA detection with multiple probes and profile entire transcripts without an end bias. The utility of HybriSeq is demonstrated in characterizing cell-to-cell heterogeneities of a panel of 196 genes in peripheral blood mononuclear cells and the detection of missed annotations of transcripts. Subject terms: Gene expression profiling,RNA sequencing View Publication

Cytolysin A (ClyA) is a pore‐forming protein from a strongly silenced gene in non‐pathogenic Escherichia coli,including typical commensal isolates in the intestinal microbiome of healthy mammalian hosts. Upon overproduction,ClyA‐expressing bacteria display a cytolytic phenotype. However,it remains unclear whether sublytic amounts of native ClyA play a role in commensal E. coli ‐host interactions in vivo. Here,we show that sublytic amounts of ClyA are released via outer membrane vesicles (OMVs) and affect host cells in a remarkable manner. OMVs isolated from ClyA + E. coli were internalised into cultured colon cancer cells. The OMV‐associated ClyA caused reduced levels of cancer‐activating proteins such as H3K27me3,CXCR4,STAT3 and MDM2 via the EZH2/H3K27me3/microRNA 622/CXCR4 signalling axis. Our results demonstrate that sublytic amounts of ClyA in OMVs from non‐pathogenic E. coli can influence the stability of the EZH2 protein,reducing its activity in epigenetic regulation,causing elevated level of the tumour suppressor protein p53. View Publication