Disruption of endocytic trafficking protein Rab7 impairs invasiveness of cholangiocarcinoma cells.

BACKGROUND: Alterations and mutations of endo-lysosomal trafficking proteins have been associated with cancer progression. Identification and characterization of endo-lysosomal trafficking proteins in invasive cholangiocarcinoma (CCA) cells may benefit prognosis and drug design for CCA. OBJECTIVE: To identify and characterize endo-lysosomal trafficking proteins in invasive CCA. METHODS: A lysosomal-enriched fraction was isolated from a TNF-α induced invasive CCA cell line (KKU-100) and uninduced control cells and protein identification was performed with nano-LC MS/MS. Novel lysosomal proteins that were upregulated in invasive CCA cells were validated by real-time RT-PCR. We selected Rab7 for further studies of protein level using western blotting and subcellular localization using immunofluorescence. The role of Rab7 in CCA invasion was determined by siRNA gene knockdown and matrigel transwell assay. RESULTS: Rab7 mRNA and protein were upregulated in invasive CCA cells compared with non-treated controls. Immunofluorescence studies demonstrated that Rab7 was expressed predominantly in invasive CCA cells and was localized in the cytoplasm and lysosomes. Suppression of Rab7 translation significantly inhibited TNF-α-induced cell invasion compared to non-treated control (p= 0.044). CONCLUSIONS: Overexpression of Rab7 in CCA cells was associated with cell invasion, supporting Rab7 as a novel candidate for the development of diagnostic and therapeutic strategies for CCA.

HEPATIC LYMPHOMA AND SPLENIC ASPERGILLOSIS MIMICKING HEPATOSPLENIC ABSCESSES FROM MELIOIDOSIS IN THAILAND.

We report here a case of hepatic lymphoma and splenic aspergillosis in an elderly patient with diabetes mellitus, exhibiting hepatosplenic abscesses mimicking melioidosis. Immunohistochemistry confirmed the diagnosis of a diffuse hepatic large B-cell lymphoma. Biopsy of the spleen revealed a clump of fungus with a slender shape and dichotomous branching, morphologically consistent with aspergillosis. Hepatosplenic abscesses are a common presentation in melioidosis, but this case reveals this assumption can lead to misdiagnosis. Histological and microbiological confirmation are required, especially in patients with hepatosplenic lesions.

Differences in Liver Impairment Between Adults and Children with Dengue Infection.

Dengue infection (DI) is a major vector-borne disease in southeast Asia and an important cause of morbidity. The complications such as hepatic impairment are common, and because the physiology of the liver differs between children and adults, the DI-associated liver impairments might be expected to differ as well. This study aims to compare the differences in liver impairment between adults and children with DI. We retrospectively studied 158 adults and 79 children with serologically confirmed DI admitted to the Bangkok Hospital for Tropical Diseases from 2008 to 2012. In total, 93% of adults and 87% of children exhibited abnormal liver enzyme levels during hospitalization. Overall, 76 (42.4%) adults and 16 (20.3%) children had dengue hemorrhagic fever (DHF). Compared with children, adults with dengue fever (DF) presented a significantly higher incidence of liver function impairment (alanine transaminase [ALT] > 2 × upper limit of normal [ULN]) (47.1% versus 25.5%), hepatitis (ALT > 4 × ULN) (29.4% versus 12.8%), and severe hepatitis (aspartate transaminase [AST]/ALT > 10 × ULN) (16.5% versus 4.3%). Children with DHF showed a significantly higher incidence of liver function impairment due to AST derangement than did adults (100% versus 73%). There were no differences in the total bilirubin, albumin, or total protein levels between adults and children. Liver enzymes normalized significantly more slowly in adults, and AST recovery was faster than ALT. In conclusion, liver function impairment was more common among adults than children with DF. As the severity progressed to DHF, liver injury became more common in children.