Combined portal and hepatic vein embolisation in perihilar cholangiocarcinoma

Background: Major hepatectomy in perihilar cholangiocarcinoma (pCCA) patients with a small future liver remnant (FLR) risks posthepatectomy liver failure (PHLF). This study examines combined portal and hepatic vein embolisation (PVE/HVE) to increase preoperative FLR volume and potentially decrease PHLF rates. Methods: In this retrospective, multicentre, observational study, data was collected from centres affiliated with the DRAGON Trials Collaborative and the EuroLVD registry. The study included pCCA patients who underwent PVE/HVE between July 2016 and January 2023. Results: Following PVE/HVE, 28% of patients (9/32) experienced complications, with 22% (7/32) necessitating biliary interventions for cholangitis. The median degree of hypertrophy after a median of 16 days was 16% with a kinetic growth rate of 6.8% per week. 69% of patients (22/32) ultimately underwent surgical resection. Cholangitis after PVE/HVE was associated with unresectability. After resection, 55% of patients (12/22) experienced complications, of which 23% (5/22) were Clavien-Dindo grade III or higher. The 90-day mortality after resection was 0%. Conclusion: PVE/HVE quickly enhances the kinetic growth rate in pCCA patients. Cholangitis impairs chances on resection significantly. Resection after PVE/HVE is associated with low levels of 90-day mortality. The study highlights the potential of PVE/HVE in improving safety and outcomes in pCCA undergoing resection

The tumour-associated antigen L6 (L6-Ag) is recruited to the tetraspanin-enriched microdomains: implication for tumour cell motility

Tumour-associated antigen L6 (L6-Ag, also known as TM4SF1) regulates tumour cell motility and invasiveness. We found that L6-Ag is abundant on the plasma membrane and on intracellular vesicles, on which it is co-localised with the markers for late endosomal/lysosomal compartments, including Lamp1/Lamp2 proteins and LBPA. Antibody internalisation and live-imaging experiments suggested that L6-Ag is targeted to late endocytic organelles (LEO) predominantly via a biosynthetic pathway. Mapping experiments showed that the presence of transmembrane regions is sufficient for directing L6-Ag to LEO. On the plasma membrane, L6-Ag is associated with tetraspanin-enriched microdomains (TERM). All three predicted cytoplasmic regions of L6-Ag are crucial for the effective recruitment of the protein to TERM. Recruitment to TERM correlated with the pro-migratory activity of L6-Ag. Depletion of L6-Ag with siRNA has a selective effect on the surface expression of tetraspanins CD63 and CD82. By contrast, the expression levels of other tetraspanins and β1 integrins was not affected. We found that L6-Ag is ubiquitylated and that ubiquitylation is essential for its function in cell migration. These data suggest that L6-Ag influences cell motility via TERM by regulating the surface presentation and endocytosis of some of their components