Identification of flucloxacillin-modified hepatocellular proteins: implications in flucloxacillin-induced liver injury.

Flucloxacillin is a ß-lactam antibiotic associated with a high incidence of drug-induced liver injury. Although expression of HLA-B*57:01 is associated with increased susceptibility, little is known of the pathological mechanisms involved in the induction of the clinical phenotype. Irreversible protein modification is suspected to drive the reaction through the provision of flucloxacillin-modified peptides that are presented to T-cells by the protein encoded by the risk allele. In this study, we have shown that flucloxacillin binds to multiple proteins within human primary hepatocytes, including major hepatocellular proteins (hemoglobin and albumin) and mitochondrial proteins. Inhibition of membrane transporters multidrug resistance-associated protein 2 (MRP2) and P-glycoprotein (P-gp) appeared to reduce the levels of covalent binding. A diverse range of proteins with different functions was found to be targeted by flucloxacillin, including adaptor proteins (14-3-3), proteins with catalytic activities (liver carboxylesterase 1, tRNA-splicing endonuclease subunit Sen2, All-trans-retinol dehydrogenase ADH1B, Glutamate dehydrogenase 1 mitochondrial, Carbamoyl-phosphate synthase [ammonia] mitochondrial), and transporters (hemoglobin, albumin, and UTP-glucose-1-phosphate uridylyltransferase). These flucloxacillin-modified intracellular proteins could provide a potential source of neoantigens for HLA-B*57:01 presentation by hepatocytes. More importantly, covalent binding to critical cellular proteins could be the molecular initiating events that lead to flucloxacillin-induced cholestasis Data are available via ProteomeXchange with identifier PXD038581.

Surgical management of suspected gallbladder cancer: The role of intraoperative frozen section for diagnostic confirmation.

BACKGROUND: Preoperative diagnosis for suspected gallbladder cancers is challenging, with a risk of overtreating benign disease, for example, xanthogranulomatous cholecystitis, with radical cholecystectomies. We retrospectively evaluated the surgeon's intraoperative assessment alone, and with the addition of intraoperative frozen sections, for suspected gallbladder cancers from a tertiary hepatobiliary multidisciplinary team (MDT). METHODS: MDT patients with complex gallbladder disease were included. Collated data included demographics, MDT discussion, operative details, and patient outcomes. RESULTS: A total of 454 patients with complex gallbladder disease were reviewed, 48 (10.6%) were offered radical surgery for suspected cancer. Twenty-five underwent frozen section that led to radical surgery in 6 (25%). All frozen sections were congruent with final histopathology but doubled the operating time (p < 0.0001). Both the surgeon's subjective and additional frozen section's objective assessment, allowed for de-escalation of unnecessary radical surgery, comparing favourably to a 13.0% cancer diagnosis among radical surgery historically. CONCLUSIONS: The MDT process was highly sensitive in identifying gallbladder cancers but lacked specificity. The surgeon's intraoperative assessment is paramount in suspected cancers, and deescalated unnecessary radical surgery. Intraoperative frozen section was a safe and viable adjunct at a cost of resources and operative time.

Prognostic and predictive markers in liver limited stage IV colorectal cancer.

Colorectal cancer is the third most commonly diagnosed cancer among both men and women. Personalised treatment options remain complex, although there is broad agreement over which patients with colorectal liver metastases (CRLM) should and should not be offered resection. Decisions on an optimal management strategy involves careful assessment of both technical and oncological factors. In this review we aim to summarise current prognostic biomarkers for metastatic colorectal cancers, specifically patients considered for resection. A number of clinico-pathological factors have been identified as prognostically important with good internal validity, but limited external validity. Furthermore, these prognostic scoring systems do not take factor in modern chemotherapeutic agents and the disease modification these agents produce. Histopathological response to chemotherapy is of significant prognostic importance. Molecular markers can help predict the efficacy of a biological agent. An important prognostic factor of liver metastasis is the recognition that location of the primary colorectal cancer impacts on metastatic phenotype and represents difference in genotype, i.e. proximal tumours are more aggressive than distal tumours with an increased likelihood of disease progression. Several mutational molecular markers identified include microsatellite instability, BRAF, and KRAS/NRAS and combination mutations, which confer poorer outcomes. Accurate prognostication in patients with liver limited colorectal metastases remains crucial, as this allows tailoring treatment options to each disease and improving outcomes. Access to tissue before treatment remains a limitation although advances in ability to assess tumour biology by non-invasive methods are promising.