Type 4 P-type ATPases (flippases) are implicated in the generation of phospholipid asymmetry in membranes by the inward translocation of phospholipids. In budding yeast, the DRS2/DNF family members Lem3p-Dnf1p/Dnf2p and Cdc50p-Drs2p are putative flippases that are localized, respectively, to the plasma membrane and endosomal/trans-Golgi network (TGN) compartments. Herein, we identified a protein kinase gene, FPK1, as a mutation that exhibited synthetic lethality with the cdc50Δ mutation. The kinase domain of Fpk1p exhibits high homology to plant phototropins and the fungus Neurospora crassa NRC-2, both of which have membrane-associated functions. Simultaneous disruption of FPK1 and its homolog FPK2 phenocopied the lem3Δ/dnf1Δ dnf2Δ mutants, exhibiting the impaired NBD-labeled phospholipid uptake, defects in the early endosome-to-TGN pathway in the absence of CDC50, and hyperpolarized bud growth after exposure of phosphatidylethanolamine at the bud tip. The fpk1Δ fpk2Δ mutation did not affect the subcellular localization of Lem3p-Dnf1p or Lem3p-Dnf2p. Further, the purified glutathione S-transferase (GST)-fused kinase domain of Fpk1p phosphorylated immunoprecipitated Dnf1p and Dnf2p to a greater extent than Drs2p. We propose that Fpk1p/Fpk2p are upstream activating protein kinases for Lem3p-Dnf1p/Dnf2p.
Background: Identification of lymph node metastases in biliary cancer is important for determining prognosis and surgical planning, but the effectiveness of computed tomography (CT) in diagnosing node metastases of the hepatoduodenal ligament (peribiliary and retroportal nodes) or around the common hepatic artery is unknown. Methods: CT scans and pathological results from 146 patients who had undergone regional lymphadenectomy for biliary carcinoma were reviewed. To evaluate the regional lymph nodes, long- and short-axis diameters of lymph nodes were measured and axial ratios calculated (short-axis diameter/long-axis diameter). Nodes were considered round if the axial ratio exceeded 0·7. Internal lymph node structures were also evaluated. Results: The presence of a round node with a short-axis diameter exceeding 16 mm had a positive predictive value (PPV) of 56 per cent for the presence of metastatic foci, and node heterogeneity had a PPV of 64 per cent. The highest PPV (67 per cent) was obtained for round nodes greater than 18 mm in short-axis diameter, but nodes of this size and character were rare. Conclusion: CT is not useful for predicting regional lymph nodal metastases in biliary carcinoma.
6 May 2017 in Journal of Hepato-Biliary-Pancreatic Sciences
Perihilar cholangiocarcinoma has one of the poorest prognoses of all cancers. However, mortality and morbidity rates after surgical resection are 0-15% and 14-66%, respectively. Additionally, the 5-year overall survival rates are reported at 22-40%. These findings indicate that only selected patients achieve satisfactory beneficial effects from operative treatment. This retrospective study sought to investigate preoperatively available prognostic factors and establish a new preoperative staging system to predict survival after major hepatectomy of perihilar cholangiocarcinoma. We evaluated 121 consecutive patients who underwent operative exploration for perihilar cholangiocarcinoma. Univariate and multivariate analysis using the identified preoperative factors revealed that 4 factors (platelet-lymphocyte ratio [PLR] > 150, serum C-reactive protein [CRP] levels > 0.5 mg/dL, albumin levels < 3.5 g/dL, and carcinoembryonic antigen [CEA] levels > 7.0 ng/mL) were independent prognostic factors of postoperative survival. These 4 preoperative factors were allocated 1 point each. The total score was defined as the Preoperative Prognostic Score (PPS). Patients with a PPS of 0, 1, 2, or 3/4 had a 5-year survival of 84.3%, 51.3%, 46.4%, and 0%, respectively. There were also differences in the 5-year survival according to the PPS (0 vs 1 [P = .013] and 2 vs 3/4 [P < .001]). Patients with a total PPS of 3/4 had a dismal prognosis, with a median survival of 11.3 months. A new preoperative scoring system using PLR, serum CRP, albumin, and CEA levels could predict postoperative survival resection of perihilar cholangiocarcinoma.