Pathological Significance of Kidney and Brain Expressed Protein (KIBRA) in Clear Cell Renal Cell Carcinoma.

BACKGROUND/AIM: Kidney and brain expressed protein (KIBRA), a member of the WW domain-containing protein family, has an important role in tumour growth and progression in various cancers. However, the pathological significance of KIBRA expression in clear cell renal cell carcinoma (ccRCC) tissues is not fully understood. The aim of this study was to clarify the pathological significance and prognostic roles of KIBRA expression in patients with ccRCC. MATERIALS AND METHODS: KIBRA immunoreactivity, proliferation index (PI; with anti-Ki-67 antibody), apoptotic index (AI; using anti-cleaved caspase-3), and large tumour suppressor kinases (LATS-2) were evaluated in 157 ccRCC specimens by immunohistochemistry. Fifty normal kidney tissues were also evaluated as controls. The relationships between KIBRA expression and these cancer-related variables as well as clinicopathological features and survival were analysed. RESULTS: Moderate to strong immunoreactivity of KIBRA was identified in all normal kidney tissues; however, ccRCC cells with strong KIBRA expression was rare. The immunoreactivity score (IRS) of KIBRA was negatively associated with grade, T stage, tumour diameter, and metastasis. Kaplan-Meier survival curves showed that high KIBRA expression was a favourite predictor for overall survival. KIBRA IRS was negatively associated with PI and positively associated with the IRS of LATS-2 by univariate analysis. In addition, multivariate analysis showed that KIBRA was significantly associated with PI. CONCLUSION: KIBRA demonstrated important roles as a tumour suppressor in ccRCC. In addition, its expression was significantly associated with survival in these patients. Several such KIBRA-related functions were speculated to be modulated by cancer cell proliferation and LATS-2.

Pathological Significance and Prognostic Roles of Thrombospondin-3, 4 and 5 in Bladder Cancer.

BACKGROUND/AIM: The pathological significance of thrombospondin (TSP)-1 and -2 in bladder cancer (BC) is well-known whereas that of TSP-3, 4 and 5 remains unclear. Our aim is to clarify the pathological significance and prognostic roles of TSP-3 to 5 expression in BC patients. PATIENTS AND METHODS: TSP-3 to 5 expression, proliferation index (PI), apoptotic index (AI) and microvessel density (MVD) were evaluated in 206 BC patients by immunohistochemical techniques. RESULTS: TSP-5 expression was positively associated with grade, T stage, metastasis, and worse prognosis. PI in TSP-5-positive tissues was significantly higher compared to negative tissues. In contrast, AI in TSP-5-positive tissues was significantly lower compared to negative tissues. Expressions of TSP-3 and 4 were not associated with any clinicopathological features, survival, PI, or AI. CONCLUSION: TSP-5 plays important roles in malignant behavior via cell survival regulation whereas the pathological significance of TSP-3 and TSP-4 in BC might be minimal.

Genes for a series of proteins that are involved in glucose catabolism are upregulated by the Hik8-cascade in Synechocystis sp. PCC 6803.

MAIN CONCLUSION: In summary, we could show the involvement of a Hik8-cascade in the expression of genes involved in the glycolytic and OPP pathways induced by GPL, and another signal pathway under photosynthetic conditions in Synechocystis . The Hik8-cascade under GPL conditions may regulate glucose degradation to produce some energy and carbon compounds. This cascade might be important for the supply of organic materials such as amino acids and nucleotides through enhancement of the rates of the glycolysis and OPP pathways. Histidine kinase Hik8 upregulates the expression of one of the important glycolytic genes, fbaA, via sll1330 under heterotrophic growth conditions (i.e., in the presence of glucose with an indispensable short period of light) in Synechocystis sp. PCC 6803. In this study, expression of the genes for the glycolytic and OPP pathways was investigated using the wild type, and disruption mutants of Hik8 and sll1330, to determine whether or not the Hik8-involving signal transduction system generally regulates glucose catabolism. In the wild type, all the genes for the glycolytic and OPP pathways were upregulated under the same conditions as for fbaA. Analyses of the disruption mutants suggested that the signal transduction system involving Hik8 and Sll1330 plays a key role in the upregulation of genes such as pfkA, pgmB, and glk, and also that Hik8 induces genes including gap1 and pgk independently of Sll1330. This complicated signal transduction cascade, designated as the Hik8-cascade, occurs under heterotrophic growth with light pulses. In addition, a disruption mutant of a putative histidine kinase, sll1334, exhibited growth and gene expression patterns that suggested it to be a negative regulator in the cascade. Possible histidine kinases and response regulators as candidates for other components in the cascade are discussed.

Two regulatory networks mediated by light and glucose involved in glycolytic gene expression in cyanobacteria.

Fructose 1,6-bisphosphate aldolase (FBA) is an enzyme involved in both glycolytic and photosynthetic reactions in photosynthetic organisms. In prokaryotes, the bidirectional reaction proceeds in the same cellular compartment, i.e. the cytoplasm. Expression of the FBA gene, fbaA, is induced through two independent pathways, stimulated by continuous light and by glucose plus pulsed light (GPL), in a cyanobactrium, Synechocystis sp. PCC 6803. Under GPL conditions, glucose can be replaced by glucose analogs that are not even metabolized in a cell. Analyses of transcripts in deletion mutants suggested that both a histidine kinase, Hik8, and a response regulator, Sll1330, played important roles as signal components in fbaA expression under GPL conditions, but not under photosynthetic conditions. Analysis of a transformant in which sll1330 expression was enhanced demonstrated that fbaA expression was induced at least partially even without glucose, but for its further induction a pulsed light stimulus was required. These results substantiated that there are two light-dependent regulatory pathways for aldolase gene expression in this cyanobacterium.