ABSTRACT
Spectrins are a group of cytoskeletal proteins which participate in many important cellular functions. It has been suggested that loss of spectrin isoforms may be associated with tumorigenesis of lymphoma, leukemia, gastric cancer and hepatocellular carcinoma (HCC). We recently reported that ßI spectrin expression was present in normal hepatocytes but lost in HCC cells, which suggested that spectrins may be helpful markers in diagnosis of HCC. In this study, using immunohistochemical staining, we further investigated the expression pattern of four spectrin isoforms (αII, ßI-III) on different benign and malignant liver tumors including focal nodular hyperplasia (FNH), hepatic adenoma (HA), HCC, and cholangiocarcinoma (CC). The results revealed that ßI spectrin was moderately to strongly positive in FNH and HA tissues, but was only weakly positive or lost in HCC cases and was weakly positive in all CC cases. In addition, the ßIII spectrin, majority of which was moderately positive in both FNH and HA tissues, was mostly lost in poorly differentiated HCC but remained at least moderately positive in most CC cases. These results suggest that spectrins ßI and ßIII may be used to differentiate well differentiated HCC from FNH or HA, and poorly differentiated HCC from CC, respectively.
Subject(s)
Biomarkers, Tumor/metabolism , Carcinoma, Hepatocellular/diagnosis , Liver Neoplasms/diagnosis , Spectrin/metabolism , Adenoma, Liver Cell/metabolism , Adolescent , Adult , Aged , Bile Duct Neoplasms/metabolism , Carcinoma, Hepatocellular/metabolism , Cell Differentiation , Child , Cholangiocarcinoma/metabolism , Female , Focal Nodular Hyperplasia/metabolism , Gene Expression Regulation, Neoplastic , Humans , Liver Neoplasms/metabolism , Male , Middle Aged , Retrospective Studies , Young AdultABSTRACT
Programmed cell death (PCD) is a highly conserved process that occurs during development and in response to adverse conditions. In Drosophila, most PCDs require the genes within the H99 deficiency, the adaptor molecule Ark, and caspases. Here we investigate 10 cell death genes for their potential roles in two distinct types of PCD that occur in oogenesis: developmental nurse cell PCD and starvation-induced PCD. Most of the genes investigated were found to have little effect on late stage developmental PCD in oogenesis, although ark mutants showed a partial inhibition. Mid-stage starvation-induced germline PCD was found to be independent of the upstream activators and ark although it requires caspases, suggesting an apoptosome-independent mechanism of caspase activation in mid-oogenesis. These results indicate that novel pathways must control PCD in the ovary.
