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Hepatocellular carcinomas (HCCs) and bile duct carcinomas (BDCs) have a poor prognosis. Therefore, surveillance strategies including sensitive and specific serum markers for early detection are needed. Recently, Golgi Phosphoprotein 2 (GOLPH2) has been proposed as a serum marker for HCC, but GOLPH2 expression data in liver tissues was not available. Using tissue microarrays and immunohistochemistry, we semiquantitatively analyzed GOLPH2 protein expression in patients with HCC (n ‫؍‬ 170), benign liver tumors (n ‫؍‬ 22), BDC (n ‫؍‬ 114) and normal liver tissue (n ‫؍‬ 105). A newly designed sandwich enzyme-linked immunoassay (ELISA) was used to analyze GOLPH2 levels in the sera of patients with HCC (n ‫؍‬ 62), hepatitis C virus (HCV) (n ‫؍‬ 29), BDC (n ‫؍‬ 10), and healthy control persons (n ‫؍‬ 12). By immunohistochemistry 121/170 (71%) of HCC showed strong GOLPH2 expression, which was significantly associated with a higher tumor grade (P ‫؍‬ 0.01). A total of 97/114 (85%) BDCs showed a strong GOLPH2 expression which proved to be an independent prognostic factor for overall survival (P < 0.05). Serum levels of GOLPH2 measured by ELISA were significantly elevated in patients with HCC with underlying HCV infection (median 18 mg/L, P < 0.05) and patients with BDC (median ‫؍‬ 14.5 mg/L, P < 0.01) in comparison to healthy controls (median 4 mg/L). Conclusion: GOLPH2 protein is highly expressed in tissues of HCC and BDC. GOLPH2 protein levels are detectable and quantifiable in sera by ELISA. In patients with hepatitis C, serial ELISA measurements in the course of the disease appear to be a promising complementary serum marker in the surveillance of HCC. GOLPH2 should be further evaluated as a serum tumor marker in BDC on a larger scale.

We report here the identification of a bacterial protein capable of interacting with mammalian death receptors in vitro and in vivo. The protein is encoded in the genome of Chlamydia trachomatis and has homologues in other Chlamydia species. This protein, which we refer to as "Chlamydia protein associating with death domains" (CADD), induces apoptosis in a variety of mammalian cell lines when expressed by transient gene transfection. Apoptosis induction can be blocked by Caspase inhibitors, indicating that CADD triggers cell death by engaging the host apoptotic machinery. CADD interacts with death domains of tumor necrosis factor (TNF) family receptors TNFR1, Fas, DR4, and DR5 but not with the respective downstream adaptors. In infected epithelial cells, CADD is expressed late in the infectious cycle of C. trachomatis and co-localizes with Fas in the proximity of the inclusion body. The results suggest a role for CADD modulating the apoptosis pathways of cells infected, revealing a new mechanism of host-pathogen interaction.Chlamydia trachomatis is a eubacterial pathogen accounting for the major cause of blindness in Asia and Africa and is the most common sexually transmitted disease in the United States. Chronic Chlamydia infections have also been linked to cancer (1, 2).Chlamydiae are obligate intracellular bacteria. Cytotoxicity associated with Chlamydia infection is well recognized and has been linked to induction of apoptosis (3-5). However, controversy exists as to the nature of the apoptotic mechanisms, and more than one route to cell death may be utilized depending on the host cell type involved (epithelial cell versus macrophage), examination of infected versus neighboring cells, and other issues (3,5).Apoptosis induction by Chlamydiae appears to be independent of host cell protein synthesis under conditions where bacterial protein synthesis remains intact (4, 6). This observation has led to the postulation that Chlamydiae encode factors capable of regulating programmed cell death of host cells (4).Using bioinformatics approaches to study Chlamydiae genomes, we identified hypothetical proteins that share significant amino acid sequence homology to the death domains (DDs) 1 of members of the mammalian TNF receptor family. In this report, the corresponding gene from C. trachomatis was cloned from bacterial genomic DNA, expressed, and functionally characterized. MATERIALS AND METHODSCloning of CADD-Chlamydia proteins with significant similarity to mammalian DDs were identified using Saturated Blast searches. A representative set of DDs was used as queries, and a cascade of TBLASTN and PSI-BLAST searches was performed on nucleotide data bases at NCBI (htgs, gss, and dbest) and the NR protein data base. The candidate DDs were confirmed by running a FFAS sequence comparison (7) against a data base of proteins of known structure (PDB) enriched for apoptotic domains. The C. trachomatis hypothetical protein CT610 (GI accession no. 3329055) had 26% identity and a FFAS Z-score of 9.3 (similarity measure) with huma...

The Chlamydia protein CADD (Chlamydia protein associating with death domains) has been implicated in the modulation of host cell apoptosis via binding to the death domains of tumor necrosis factor family receptors. Transfection of CADD into mammalian cells induces apoptosis. Here we present the CADD crystal structure, which reveals a dimer of seven-helix bundles. Each bundle contains a di-iron center adjacent to an internal cavity, forming an active site similar to that of methane mono-oxygenase hydrolase. We further show that CADD mutants lacking critical metal-coordinating residues are substantially less effective in inducing apoptosis but retain their ability to bind to death domains. We conclude that CADD is a novel redox protein toxin unique to Chlamydia species and propose that both its redox activity and death domain binding ability are required for its biological activity.

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Fas-associated phosphatase-1 (FAP-1) is a protein-tyrosine phosphatase that binds the cytosolic tail of Fas (Apo1, CD95), presumably regulating Fas-induced apoptosis. Elevations of FAP-1 protein levels in some tumor cell lines have been correlated with resistance to Fas-induced apoptosis. To explore the expression of FAP-1 in ovarian cancer cell lines and archival tumor specimens, mouse monoclonal and rabbit polyclonal antibodies were generated against a FAP-1 peptide and recombinant FAP-1 protein. These antibodies were used for immunoblotting, immunohistochemistry, and flow-cytometry analysis of FAP-1 expression in the Fas-sensitive ovarian cancer lines HEY and BG-1, and in the Fas-resistant lines OVCAR-3 FR and SK-OV-3. All methods demonstrated high levels of FAP-1 in the resistant lines OVCAR-3 FR and SK-OV-3, but not in the Fas-sensitive lines HEY and BG-1. Furthermore, levels of FAP-1 protein also correlated with the amounts of FAP-1 mRNA, as determined by reverse transcriptase-polymerase chain reaction analysis. FAP-1 protein levels were investigated by immunoblotting in the National Cancer Institute's panel of 60 human tumor cell lines. Although FAP-1 failed to correlate with Fas-resistance across the entire tumor panel, Fas-resistance correlated significantly with FAP-1 expression (P: < or = 0.05) and a low Fas/FAP-1 ratio (P: < or = 0.028) in ovarian cancer cell lines. FAP-1 expression was also evaluated in 95 archival ovarian cancer specimens using tissue-microarray technology. FAP-1 was expressed in nearly all tumors, regardless of histological type or grade, stage, patient age, response to chemotherapy, or patient survival. We conclude that FAP-1 correlates significantly with Fas resistance in ovarian cancer cell lines and is commonly expressed in ovarian cancers.

Pomegranate has been shown to prolong PSA doubling time in early prostate cancer, but no data from a placebo controlled trial has been published yet. The objective of this study was to prospectively evaluate the impact of pomegranate juice in patients with prostate cancer.We conducted a phase IIb, double blinded, randomized placebo controlled trial in patients with histologically confirmed prostate cancer. Only patients with a PSA value ≥ 5ng/ml were included. The subjects consumed 500 ml of pomegranate juice or 500 ml of placebo beverage every day for a 4 week period. Thereafter, all patients received 250 ml of the pomegranate juice daily for another 4 weeks. PSA values were taken at baseline, day 14, 28 and on day 56. The primary endpoint was the detection of a significant difference in PSA serum levels between the groups after one month of treatment. Pain scores and adherence to intervention were recorded using patient diaries.102 patients were enrolled. The majority of patients had castration resistant prostate cancer (68%). 98 received either pomegranate juice or placebo between October 2008 and May 2011. Adherence to protocol was good, with 94 patients (96%) completing the first period and 87 patients (89%) completing both periods. No grade 3 or higher toxicities occurred within the study. No differences were detected between the two groups with regard to PSA kinetics and pain scores.Consumption of pomegranate juice as an adjunct intervention in men with advanced prostate cancer does not result in significant PSA declines compared to placebo.

Objective: To evaluate the optimal sequence for the receptor tyrosine kinase inhibitors (rTKIs) sorafenib and sunitinib in metastatic renal cell cancer. Methods: We performed a retrospective analysis of patients who had received sequential therapy with both rTKIs and integrated these results into a pooled analysis of available data from other publications. Differences in median progression-free survival (PFS) for first- (PFS1) and second-line treatment (PFS2), and for the combined PFS (PFS1 plus PFS2) were examined using weighted linear regression. Results: In the pooled analysis encompassing 853 patients, the median combined PFS for first-line sunitinib and 2nd-line sorafenib (SuSo) was 12.1 months compared with 15.4 months for the reverse sequence (SoSu; 95% CI for difference 1.45–5.12, p = 0.0013). Regarding first-line treatment, no significant difference in PFS1 was noted regardless of which drug was initially used (0.62 months average increase on sorafenib, 95% CI for difference –1.01 to 2.26, p = 0.43). In second-line treatment, sunitinib showed a significantly longer PFS2 than sorafenib (average increase 2.66 months, 95% CI 1.02–4.3, p = 0.003). Conclusion: The SoSu sequence translates into a longer combined PFS compared to the SuSo sequence. Predominantly the superiority of sunitinib regarding PFS2 contributed to the longer combined PFS in sequential use.