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Background: The determinants of the response to checkpoint immunotherapy in hepatocellular carcinoma (HCC) remain poorly understood. The organisation of the immune response in the tumour microenvironment (TME) is expected to govern immunotherapy outcomes but spatial immunotypes remain poorly defined.

Objective: We hypothesised that the deconvolution of spatial immune network architectures could identify clinically relevant immunotypes in HCC.

Design: We conducted highly multiplexed imaging mass cytometry on HCC tissues from 101 patients. We performed in-depth spatial single-cell analysis in a discovery and validation cohort to deconvolute the determinants of the heterogeneity of HCC immune architecture and develop a spatial immune classification that was tested for the prediction of immune checkpoint inhibitor (ICI) therapy.

Results: Bioinformatic analysis identified 23 major immune, stroma, parenchymal and tumour cell types in the HCC TME. Unsupervised neighbourhood detection based on the spatial interaction of immune cells identified three immune architectures with differing involvement of immune cells and immune checkpoints dominated by either CD8 T-cells, myeloid immune cells or B- and CD4 T-cells. We used these to define three major spatial HCC immunotypes that reflect a higher level of intratumour immune cell organisation: depleted, compartmentalised and enriched. Progression-free survival under ICI therapy differed significantly between the spatial immune types with improved survival of enriched patients. In patients with intratumour heterogeneity, the presence of one enriched area governed long-term survival.

Background: The potency of T cell-mediated responses is a determinant of immunotherapy effectiveness in treating malignancies; however, the clinical efficacy of T-cell therapies has been limited in hepatocellular carcinoma (HCC) owing to the extensive immunosuppressive microenvironment.

Objective: Here, we aimed to investigate the key genes contributing to immune escape in HCC and raise a new therapeutic strategy for remoulding the HCC microenvironment.

Design: The genome-wide in vivo clustered regularly interspaced short palindromic repeats (CRISPR) screen library was conducted to identify the key genes associated with immune tolerance. Single-cell RNA-seq (scRNA-seq), flow cytometry, HCC mouse models, chromatin immunoprecipitation and coimmunoprecipitation were used to explore the function and mechanism of adenylate cyclase 7 (ADCY7) in HCC immune surveillance.

Results: Here, a genome-wide in vivo CRISPR screen identified a novel immune modulator-ADCY7. The transmembrane protein ADCY7 undergoes subcellular translocation via caveolae-mediated endocytosis and then translocates to the nucleus with the help of leucine-rich repeat-containing protein 59 (LRRC59) and karyopherin subunit beta 1 (KPNB1). In the nucleus, it functions as a transcription cofactor of CCAAT/enhancer binding protein alpha (CEBPA) to induce CCL5 transcription, thereby increasing CD8⁺ T cell infiltration to restrain HCC progression. Furthermore, ADCY7 can be secreted as exosomes and enter neighbouring tumour cells to promote CCL5 induction. Exosomes with high ADCY7 levels promote intratumoural infiltration of CD8⁺ T cells and suppress HCC tumour growth.

Conclusion: We delineate the unconventional function and subcellular location of ADCY7, highlighting its pivotal role in T cell-mediated immunity in HCC and its potential as a promising treatment target.

Background: Endoscopic retrograde cholangiopancreatography (ERCP) with fully covered self-expandable metal stent (FCSEMS) placement is the preferred approach for biliary drainage in patients with suspected distal malignant biliary obstruction (MBO). However, FCSEMS placement is associated with a high risk of post-ERCP pancreatitis (PEP). Endoscopic sphincterotomy prior to FCSEMS placement may reduce PEP risk.

Objective: To compare endoscopic sphincterotomy to no sphincterotomy prior to FCSEMS placement.

Design: This multicentre, randomised, superiority trial was conducted in 17 hospitals and included patients with suspected distal MBO. Patients were randomised during ERCP to receive either endoscopic sphincterotomy (sphincterotomy group) or no sphincterotomy (control group) prior to FCSEMS placement. The primary outcome was PEP within 30 days. Secondary outcomes included procedure-related complications and 30-day mortality. An interim analysis was performed after 50% of patients (n=259) had completed follow-up.

Results: Between May 2016 and June 2023, 297 patients were included in the intention-to-treat analysis, with 156 in the sphincterotomy group and 141 in the control group. After the interim analysis, the study was terminated prematurely due to futility. PEP did not differ between groups, occurring in 26 patients (17%) in the sphincterotomy group compared with 30 patients (21%) in the control group (relative risk 0.78, 95% CI 0.49 to 1.26, p=0.37). There were no significant differences in bleeding, perforation, cholangitis, cholecystitis or 30-day mortality.

Conclusion: This trial found that endoscopic sphincterotomy was not superior to no sphincterotomy in reducing PEP in patients with distal MBO. Therefore, there was insufficient evidence to recommend routine endoscopic sphincterotomy prior to FCEMS placement.

Trial registration number: NL5130.